diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 611172f68bb57..5e34deec819fa 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -4035,6 +4035,12 @@ fully seed the kernel's CRNG. Default is controlled by CONFIG_RANDOM_TRUST_CPU. + random.trust_bootloader={on,off} + [KNL] Enable or disable trusting the use of a + seed passed by the bootloader (if available) to + fully seed the kernel's CRNG. Default is controlled + by CONFIG_RANDOM_TRUST_BOOTLOADER. + ras=option[,option,...] [KNL] RAS-specific options cec_disable [X86] diff --git a/Documentation/admin-guide/sysctl/kernel.rst b/Documentation/admin-guide/sysctl/kernel.rst index e338306f45873..a4b1ebc2e70b0 100644 --- a/Documentation/admin-guide/sysctl/kernel.rst +++ b/Documentation/admin-guide/sysctl/kernel.rst @@ -1006,28 +1006,22 @@ This is a directory, with the following entries: * ``boot_id``: a UUID generated the first time this is retrieved, and unvarying after that; +* ``uuid``: a UUID generated every time this is retrieved (this can + thus be used to generate UUIDs at will); + * ``entropy_avail``: the pool's entropy count, in bits; * ``poolsize``: the entropy pool size, in bits; * ``urandom_min_reseed_secs``: obsolete (used to determine the minimum - number of seconds between urandom pool reseeding). - -* ``uuid``: a UUID generated every time this is retrieved (this can - thus be used to generate UUIDs at will); + number of seconds between urandom pool reseeding). This file is + writable for compatibility purposes, but writing to it has no effect + on any RNG behavior; * ``write_wakeup_threshold``: when the entropy count drops below this (as a number of bits), processes waiting to write to ``/dev/random`` - are woken up. - -If ``drivers/char/random.c`` is built with ``ADD_INTERRUPT_BENCH`` -defined, these additional entries are present: - -* ``add_interrupt_avg_cycles``: the average number of cycles between - interrupts used to feed the pool; - -* ``add_interrupt_avg_deviation``: the standard deviation seen on the - number of cycles between interrupts used to feed the pool. + are woken up. This file is writable for compatibility purposes, but + writing to it has no effect on any RNG behavior. randomize_va_space diff --git a/MAINTAINERS b/MAINTAINERS index c64c9354c287f..7c118b507912f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -14671,6 +14671,8 @@ F: arch/mips/generic/board-ranchu.c RANDOM NUMBER DRIVER M: "Theodore Ts'o" +M: Jason A. Donenfeld +T: git https://git.kernel.org/pub/scm/linux/kernel/git/crng/random.git S: Maintained F: drivers/char/random.c diff --git a/Makefile b/Makefile index f9210e43121dc..b442cc5bbfc30 100644 --- a/Makefile +++ b/Makefile @@ -1,7 +1,7 @@ # SPDX-License-Identifier: GPL-2.0 VERSION = 5 PATCHLEVEL = 10 -SUBLEVEL = 118 +SUBLEVEL = 119 EXTRAVERSION = NAME = Dare mighty things diff --git a/arch/alpha/include/asm/timex.h b/arch/alpha/include/asm/timex.h index b565cc6f408e9..f89798da8a147 100644 --- a/arch/alpha/include/asm/timex.h +++ b/arch/alpha/include/asm/timex.h @@ -28,5 +28,6 @@ static inline cycles_t get_cycles (void) __asm__ __volatile__ ("rpcc %0" : "=r"(ret)); return ret; } +#define get_cycles get_cycles #endif diff --git a/arch/arm/include/asm/timex.h b/arch/arm/include/asm/timex.h index 7c3b3671d6c25..6d1337c169cd3 100644 --- a/arch/arm/include/asm/timex.h +++ b/arch/arm/include/asm/timex.h @@ -11,5 +11,6 @@ typedef unsigned long cycles_t; #define get_cycles() ({ cycles_t c; read_current_timer(&c) ? 0 : c; }) +#define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback()) #endif diff --git a/arch/ia64/include/asm/timex.h b/arch/ia64/include/asm/timex.h index 869a3ac6bf23a..7ccc077a60bed 100644 --- a/arch/ia64/include/asm/timex.h +++ b/arch/ia64/include/asm/timex.h @@ -39,6 +39,7 @@ get_cycles (void) ret = ia64_getreg(_IA64_REG_AR_ITC); return ret; } +#define get_cycles get_cycles extern void ia64_cpu_local_tick (void); extern unsigned long long ia64_native_sched_clock (void); diff --git a/arch/m68k/include/asm/timex.h b/arch/m68k/include/asm/timex.h index 6a21d93582805..f4a7a340f4cae 100644 --- a/arch/m68k/include/asm/timex.h +++ b/arch/m68k/include/asm/timex.h @@ -35,7 +35,7 @@ static inline unsigned long random_get_entropy(void) { if (mach_random_get_entropy) return mach_random_get_entropy(); - return 0; + return random_get_entropy_fallback(); } #define random_get_entropy random_get_entropy diff --git a/arch/mips/include/asm/timex.h b/arch/mips/include/asm/timex.h index 8026baf46e729..2e107886f97ac 100644 --- a/arch/mips/include/asm/timex.h +++ b/arch/mips/include/asm/timex.h @@ -76,25 +76,24 @@ static inline cycles_t get_cycles(void) else return 0; /* no usable counter */ } +#define get_cycles get_cycles /* * Like get_cycles - but where c0_count is not available we desperately * use c0_random in an attempt to get at least a little bit of entropy. - * - * R6000 and R6000A neither have a count register nor a random register. - * That leaves no entropy source in the CPU itself. */ static inline unsigned long random_get_entropy(void) { - unsigned int prid = read_c0_prid(); - unsigned int imp = prid & PRID_IMP_MASK; + unsigned int c0_random; - if (can_use_mips_counter(prid)) + if (can_use_mips_counter(read_c0_prid())) return read_c0_count(); - else if (likely(imp != PRID_IMP_R6000 && imp != PRID_IMP_R6000A)) - return read_c0_random(); + + if (cpu_has_3kex) + c0_random = (read_c0_random() >> 8) & 0x3f; else - return 0; /* no usable register */ + c0_random = read_c0_random() & 0x3f; + return (random_get_entropy_fallback() << 6) | (0x3f - c0_random); } #define random_get_entropy random_get_entropy diff --git a/arch/nios2/include/asm/timex.h b/arch/nios2/include/asm/timex.h index a769f871b28d9..40a1adc9bd03e 100644 --- a/arch/nios2/include/asm/timex.h +++ b/arch/nios2/include/asm/timex.h @@ -8,5 +8,8 @@ typedef unsigned long cycles_t; extern cycles_t get_cycles(void); +#define get_cycles get_cycles + +#define random_get_entropy() (((unsigned long)get_cycles()) ?: random_get_entropy_fallback()) #endif diff --git a/arch/parisc/include/asm/timex.h b/arch/parisc/include/asm/timex.h index 06b510f8172e3..b4622cb06a75e 100644 --- a/arch/parisc/include/asm/timex.h +++ b/arch/parisc/include/asm/timex.h @@ -13,9 +13,10 @@ typedef unsigned long cycles_t; -static inline cycles_t get_cycles (void) +static inline cycles_t get_cycles(void) { return mfctl(16); } +#define get_cycles get_cycles #endif diff --git a/arch/powerpc/include/asm/timex.h b/arch/powerpc/include/asm/timex.h index 95988870a57bc..171602fd358e1 100644 --- a/arch/powerpc/include/asm/timex.h +++ b/arch/powerpc/include/asm/timex.h @@ -19,6 +19,7 @@ static inline cycles_t get_cycles(void) { return mftb(); } +#define get_cycles get_cycles #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_TIMEX_H */ diff --git a/arch/riscv/include/asm/timex.h b/arch/riscv/include/asm/timex.h index 81de51e6aa32b..a06697846e695 100644 --- a/arch/riscv/include/asm/timex.h +++ b/arch/riscv/include/asm/timex.h @@ -41,7 +41,7 @@ static inline u32 get_cycles_hi(void) static inline unsigned long random_get_entropy(void) { if (unlikely(clint_time_val == NULL)) - return 0; + return random_get_entropy_fallback(); return get_cycles(); } #define random_get_entropy() random_get_entropy() diff --git a/arch/s390/include/asm/timex.h b/arch/s390/include/asm/timex.h index 289aaff4d365f..588aa0f2c842c 100644 --- a/arch/s390/include/asm/timex.h +++ b/arch/s390/include/asm/timex.h @@ -172,6 +172,7 @@ static inline cycles_t get_cycles(void) { return (cycles_t) get_tod_clock() >> 2; } +#define get_cycles get_cycles int get_phys_clock(unsigned long *clock); void init_cpu_timer(void); diff --git a/arch/sparc/include/asm/timex_32.h b/arch/sparc/include/asm/timex_32.h index 542915b462097..f86326a6f89e0 100644 --- a/arch/sparc/include/asm/timex_32.h +++ b/arch/sparc/include/asm/timex_32.h @@ -9,8 +9,6 @@ #define CLOCK_TICK_RATE 1193180 /* Underlying HZ */ -/* XXX Maybe do something better at some point... -DaveM */ -typedef unsigned long cycles_t; -#define get_cycles() (0) +#include #endif diff --git a/arch/um/include/asm/timex.h b/arch/um/include/asm/timex.h index e392a9a5bc9bd..9f27176adb26d 100644 --- a/arch/um/include/asm/timex.h +++ b/arch/um/include/asm/timex.h @@ -2,13 +2,8 @@ #ifndef __UM_TIMEX_H #define __UM_TIMEX_H -typedef unsigned long cycles_t; - -static inline cycles_t get_cycles (void) -{ - return 0; -} - #define CLOCK_TICK_RATE (HZ) +#include + #endif diff --git a/arch/x86/crypto/Makefile b/arch/x86/crypto/Makefile index a31de0c6ccde2..66f25c2938bfe 100644 --- a/arch/x86/crypto/Makefile +++ b/arch/x86/crypto/Makefile @@ -66,7 +66,9 @@ obj-$(CONFIG_CRYPTO_SHA512_SSSE3) += sha512-ssse3.o sha512-ssse3-y := sha512-ssse3-asm.o sha512-avx-asm.o sha512-avx2-asm.o sha512_ssse3_glue.o obj-$(CONFIG_CRYPTO_BLAKE2S_X86) += blake2s-x86_64.o -blake2s-x86_64-y := blake2s-core.o blake2s-glue.o +blake2s-x86_64-y := blake2s-shash.o +obj-$(if $(CONFIG_CRYPTO_BLAKE2S_X86),y) += libblake2s-x86_64.o +libblake2s-x86_64-y := blake2s-core.o blake2s-glue.o obj-$(CONFIG_CRYPTO_GHASH_CLMUL_NI_INTEL) += ghash-clmulni-intel.o ghash-clmulni-intel-y := ghash-clmulni-intel_asm.o ghash-clmulni-intel_glue.o diff --git a/arch/x86/crypto/blake2s-glue.c b/arch/x86/crypto/blake2s-glue.c index c025a01cf7084..69853c13e8fb0 100644 --- a/arch/x86/crypto/blake2s-glue.c +++ b/arch/x86/crypto/blake2s-glue.c @@ -5,7 +5,6 @@ #include #include -#include #include #include @@ -28,9 +27,8 @@ asmlinkage void blake2s_compress_avx512(struct blake2s_state *state, static __ro_after_init DEFINE_STATIC_KEY_FALSE(blake2s_use_ssse3); static __ro_after_init DEFINE_STATIC_KEY_FALSE(blake2s_use_avx512); -void blake2s_compress_arch(struct blake2s_state *state, - const u8 *block, size_t nblocks, - const u32 inc) +void blake2s_compress(struct blake2s_state *state, const u8 *block, + size_t nblocks, const u32 inc) { /* SIMD disables preemption, so relax after processing each page. */ BUILD_BUG_ON(SZ_4K / BLAKE2S_BLOCK_SIZE < 8); @@ -56,147 +54,12 @@ void blake2s_compress_arch(struct blake2s_state *state, block += blocks * BLAKE2S_BLOCK_SIZE; } while (nblocks); } -EXPORT_SYMBOL(blake2s_compress_arch); - -static int crypto_blake2s_setkey(struct crypto_shash *tfm, const u8 *key, - unsigned int keylen) -{ - struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm); - - if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE) - return -EINVAL; - - memcpy(tctx->key, key, keylen); - tctx->keylen = keylen; - - return 0; -} - -static int crypto_blake2s_init(struct shash_desc *desc) -{ - struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); - struct blake2s_state *state = shash_desc_ctx(desc); - const int outlen = crypto_shash_digestsize(desc->tfm); - - if (tctx->keylen) - blake2s_init_key(state, outlen, tctx->key, tctx->keylen); - else - blake2s_init(state, outlen); - - return 0; -} - -static int crypto_blake2s_update(struct shash_desc *desc, const u8 *in, - unsigned int inlen) -{ - struct blake2s_state *state = shash_desc_ctx(desc); - const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen; - - if (unlikely(!inlen)) - return 0; - if (inlen > fill) { - memcpy(state->buf + state->buflen, in, fill); - blake2s_compress_arch(state, state->buf, 1, BLAKE2S_BLOCK_SIZE); - state->buflen = 0; - in += fill; - inlen -= fill; - } - if (inlen > BLAKE2S_BLOCK_SIZE) { - const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE); - /* Hash one less (full) block than strictly possible */ - blake2s_compress_arch(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE); - in += BLAKE2S_BLOCK_SIZE * (nblocks - 1); - inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1); - } - memcpy(state->buf + state->buflen, in, inlen); - state->buflen += inlen; - - return 0; -} - -static int crypto_blake2s_final(struct shash_desc *desc, u8 *out) -{ - struct blake2s_state *state = shash_desc_ctx(desc); - - blake2s_set_lastblock(state); - memset(state->buf + state->buflen, 0, - BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */ - blake2s_compress_arch(state, state->buf, 1, state->buflen); - cpu_to_le32_array(state->h, ARRAY_SIZE(state->h)); - memcpy(out, state->h, state->outlen); - memzero_explicit(state, sizeof(*state)); - - return 0; -} - -static struct shash_alg blake2s_algs[] = {{ - .base.cra_name = "blake2s-128", - .base.cra_driver_name = "blake2s-128-x86", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_128_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}, { - .base.cra_name = "blake2s-160", - .base.cra_driver_name = "blake2s-160-x86", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_160_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}, { - .base.cra_name = "blake2s-224", - .base.cra_driver_name = "blake2s-224-x86", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_224_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}, { - .base.cra_name = "blake2s-256", - .base.cra_driver_name = "blake2s-256-x86", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_256_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}}; +EXPORT_SYMBOL(blake2s_compress); static int __init blake2s_mod_init(void) { - if (!boot_cpu_has(X86_FEATURE_SSSE3)) - return 0; - - static_branch_enable(&blake2s_use_ssse3); + if (boot_cpu_has(X86_FEATURE_SSSE3)) + static_branch_enable(&blake2s_use_ssse3); if (IS_ENABLED(CONFIG_AS_AVX512) && boot_cpu_has(X86_FEATURE_AVX) && @@ -207,26 +70,9 @@ static int __init blake2s_mod_init(void) XFEATURE_MASK_AVX512, NULL)) static_branch_enable(&blake2s_use_avx512); - return IS_REACHABLE(CONFIG_CRYPTO_HASH) ? - crypto_register_shashes(blake2s_algs, - ARRAY_SIZE(blake2s_algs)) : 0; -} - -static void __exit blake2s_mod_exit(void) -{ - if (IS_REACHABLE(CONFIG_CRYPTO_HASH) && boot_cpu_has(X86_FEATURE_SSSE3)) - crypto_unregister_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs)); + return 0; } module_init(blake2s_mod_init); -module_exit(blake2s_mod_exit); -MODULE_ALIAS_CRYPTO("blake2s-128"); -MODULE_ALIAS_CRYPTO("blake2s-128-x86"); -MODULE_ALIAS_CRYPTO("blake2s-160"); -MODULE_ALIAS_CRYPTO("blake2s-160-x86"); -MODULE_ALIAS_CRYPTO("blake2s-224"); -MODULE_ALIAS_CRYPTO("blake2s-224-x86"); -MODULE_ALIAS_CRYPTO("blake2s-256"); -MODULE_ALIAS_CRYPTO("blake2s-256-x86"); MODULE_LICENSE("GPL v2"); diff --git a/arch/x86/crypto/blake2s-shash.c b/arch/x86/crypto/blake2s-shash.c new file mode 100644 index 0000000000000..59ae28abe35cc --- /dev/null +++ b/arch/x86/crypto/blake2s-shash.c @@ -0,0 +1,77 @@ +// SPDX-License-Identifier: GPL-2.0 OR MIT +/* + * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. + */ + +#include +#include +#include + +#include +#include +#include +#include + +#include +#include + +static int crypto_blake2s_update_x86(struct shash_desc *desc, + const u8 *in, unsigned int inlen) +{ + return crypto_blake2s_update(desc, in, inlen, false); +} + +static int crypto_blake2s_final_x86(struct shash_desc *desc, u8 *out) +{ + return crypto_blake2s_final(desc, out, false); +} + +#define BLAKE2S_ALG(name, driver_name, digest_size) \ + { \ + .base.cra_name = name, \ + .base.cra_driver_name = driver_name, \ + .base.cra_priority = 200, \ + .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, \ + .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, \ + .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), \ + .base.cra_module = THIS_MODULE, \ + .digestsize = digest_size, \ + .setkey = crypto_blake2s_setkey, \ + .init = crypto_blake2s_init, \ + .update = crypto_blake2s_update_x86, \ + .final = crypto_blake2s_final_x86, \ + .descsize = sizeof(struct blake2s_state), \ + } + +static struct shash_alg blake2s_algs[] = { + BLAKE2S_ALG("blake2s-128", "blake2s-128-x86", BLAKE2S_128_HASH_SIZE), + BLAKE2S_ALG("blake2s-160", "blake2s-160-x86", BLAKE2S_160_HASH_SIZE), + BLAKE2S_ALG("blake2s-224", "blake2s-224-x86", BLAKE2S_224_HASH_SIZE), + BLAKE2S_ALG("blake2s-256", "blake2s-256-x86", BLAKE2S_256_HASH_SIZE), +}; + +static int __init blake2s_mod_init(void) +{ + if (IS_REACHABLE(CONFIG_CRYPTO_HASH) && boot_cpu_has(X86_FEATURE_SSSE3)) + return crypto_register_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs)); + return 0; +} + +static void __exit blake2s_mod_exit(void) +{ + if (IS_REACHABLE(CONFIG_CRYPTO_HASH) && boot_cpu_has(X86_FEATURE_SSSE3)) + crypto_unregister_shashes(blake2s_algs, ARRAY_SIZE(blake2s_algs)); +} + +module_init(blake2s_mod_init); +module_exit(blake2s_mod_exit); + +MODULE_ALIAS_CRYPTO("blake2s-128"); +MODULE_ALIAS_CRYPTO("blake2s-128-x86"); +MODULE_ALIAS_CRYPTO("blake2s-160"); +MODULE_ALIAS_CRYPTO("blake2s-160-x86"); +MODULE_ALIAS_CRYPTO("blake2s-224"); +MODULE_ALIAS_CRYPTO("blake2s-224-x86"); +MODULE_ALIAS_CRYPTO("blake2s-256"); +MODULE_ALIAS_CRYPTO("blake2s-256-x86"); +MODULE_LICENSE("GPL v2"); diff --git a/arch/x86/include/asm/timex.h b/arch/x86/include/asm/timex.h index a4a8b1b16c0c1..956e4145311b1 100644 --- a/arch/x86/include/asm/timex.h +++ b/arch/x86/include/asm/timex.h @@ -5,6 +5,15 @@ #include #include +static inline unsigned long random_get_entropy(void) +{ + if (!IS_ENABLED(CONFIG_X86_TSC) && + !cpu_feature_enabled(X86_FEATURE_TSC)) + return random_get_entropy_fallback(); + return rdtsc(); +} +#define random_get_entropy random_get_entropy + /* Assume we use the PIT time source for the clock tick */ #define CLOCK_TICK_RATE PIT_TICK_RATE diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h index 01a300a9700b9..fbdc3d9514943 100644 --- a/arch/x86/include/asm/tsc.h +++ b/arch/x86/include/asm/tsc.h @@ -20,13 +20,12 @@ extern void disable_TSC(void); static inline cycles_t get_cycles(void) { -#ifndef CONFIG_X86_TSC - if (!boot_cpu_has(X86_FEATURE_TSC)) + if (!IS_ENABLED(CONFIG_X86_TSC) && + !cpu_feature_enabled(X86_FEATURE_TSC)) return 0; -#endif - return rdtsc(); } +#define get_cycles get_cycles extern struct system_counterval_t convert_art_to_tsc(u64 art); extern struct system_counterval_t convert_art_ns_to_tsc(u64 art_ns); diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index 65d11711cd7bb..021cd067733e3 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -84,7 +84,7 @@ DEFINE_IDTENTRY_SYSVEC(sysvec_hyperv_stimer0) inc_irq_stat(hyperv_stimer0_count); if (hv_stimer0_handler) hv_stimer0_handler(); - add_interrupt_randomness(HYPERV_STIMER0_VECTOR, 0); + add_interrupt_randomness(HYPERV_STIMER0_VECTOR); ack_APIC_irq(); set_irq_regs(old_regs); diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index a3ef793fce5f1..6ed6b090be941 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -297,6 +297,10 @@ static inline void apic_set_spiv(struct kvm_lapic *apic, u32 val) atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY); } + + /* Check if there are APF page ready requests pending */ + if (enabled) + kvm_make_request(KVM_REQ_APF_READY, apic->vcpu); } static inline void kvm_apic_set_xapic_id(struct kvm_lapic *apic, u8 id) @@ -2260,6 +2264,8 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value) if (value & MSR_IA32_APICBASE_ENABLE) { kvm_apic_set_xapic_id(apic, vcpu->vcpu_id); static_key_slow_dec_deferred(&apic_hw_disabled); + /* Check if there are APF page ready requests pending */ + kvm_make_request(KVM_REQ_APF_READY, vcpu); } else { static_key_slow_inc(&apic_hw_disabled.key); atomic_set_release(&apic->vcpu->kvm->arch.apic_map_dirty, DIRTY); diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 306268f90455f..6096d0f1a62af 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -5178,14 +5178,16 @@ void kvm_mmu_invpcid_gva(struct kvm_vcpu *vcpu, gva_t gva, unsigned long pcid) uint i; if (pcid == kvm_get_active_pcid(vcpu)) { - mmu->invlpg(vcpu, gva, mmu->root_hpa); + if (mmu->invlpg) + mmu->invlpg(vcpu, gva, mmu->root_hpa); tlb_flush = true; } for (i = 0; i < KVM_MMU_NUM_PREV_ROOTS; i++) { if (VALID_PAGE(mmu->prev_roots[i].hpa) && pcid == kvm_get_pcid(vcpu, mmu->prev_roots[i].pgd)) { - mmu->invlpg(vcpu, gva, mmu->prev_roots[i].hpa); + if (mmu->invlpg) + mmu->invlpg(vcpu, gva, mmu->prev_roots[i].hpa); tlb_flush = true; } } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 4588f73bf59a4..ae18062c26a66 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11146,7 +11146,7 @@ bool kvm_arch_can_dequeue_async_page_present(struct kvm_vcpu *vcpu) if (!kvm_pv_async_pf_enabled(vcpu)) return true; else - return apf_pageready_slot_free(vcpu); + return kvm_lapic_enabled(vcpu) && apf_pageready_slot_free(vcpu); } void kvm_arch_start_assignment(struct kvm *kvm) diff --git a/arch/xtensa/include/asm/timex.h b/arch/xtensa/include/asm/timex.h index 233ec75e60c69..3f2462f2d0270 100644 --- a/arch/xtensa/include/asm/timex.h +++ b/arch/xtensa/include/asm/timex.h @@ -29,10 +29,6 @@ extern unsigned long ccount_freq; -typedef unsigned long long cycles_t; - -#define get_cycles() (0) - void local_timer_setup(unsigned cpu); /* @@ -59,4 +55,6 @@ static inline void set_linux_timer (unsigned long ccompare) xtensa_set_sr(ccompare, SREG_CCOMPARE + LINUX_TIMER); } +#include + #endif /* _XTENSA_TIMEX_H */ diff --git a/crypto/Kconfig b/crypto/Kconfig index 1157f82dc9cf4..0dee9242491cb 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1936,9 +1936,10 @@ config CRYPTO_STATS config CRYPTO_HASH_INFO bool -source "lib/crypto/Kconfig" source "drivers/crypto/Kconfig" source "crypto/asymmetric_keys/Kconfig" source "certs/Kconfig" endif # if CRYPTO + +source "lib/crypto/Kconfig" diff --git a/crypto/blake2s_generic.c b/crypto/blake2s_generic.c index 005783ff45ad0..5f96a21f87883 100644 --- a/crypto/blake2s_generic.c +++ b/crypto/blake2s_generic.c @@ -1,149 +1,55 @@ // SPDX-License-Identifier: GPL-2.0 OR MIT /* + * shash interface to the generic implementation of BLAKE2s + * * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. */ #include -#include #include #include -#include #include #include -static int crypto_blake2s_setkey(struct crypto_shash *tfm, const u8 *key, - unsigned int keylen) +static int crypto_blake2s_update_generic(struct shash_desc *desc, + const u8 *in, unsigned int inlen) { - struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm); - - if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE) - return -EINVAL; - - memcpy(tctx->key, key, keylen); - tctx->keylen = keylen; - - return 0; + return crypto_blake2s_update(desc, in, inlen, true); } -static int crypto_blake2s_init(struct shash_desc *desc) +static int crypto_blake2s_final_generic(struct shash_desc *desc, u8 *out) { - struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); - struct blake2s_state *state = shash_desc_ctx(desc); - const int outlen = crypto_shash_digestsize(desc->tfm); - - if (tctx->keylen) - blake2s_init_key(state, outlen, tctx->key, tctx->keylen); - else - blake2s_init(state, outlen); - - return 0; + return crypto_blake2s_final(desc, out, true); } -static int crypto_blake2s_update(struct shash_desc *desc, const u8 *in, - unsigned int inlen) -{ - struct blake2s_state *state = shash_desc_ctx(desc); - const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen; - - if (unlikely(!inlen)) - return 0; - if (inlen > fill) { - memcpy(state->buf + state->buflen, in, fill); - blake2s_compress_generic(state, state->buf, 1, BLAKE2S_BLOCK_SIZE); - state->buflen = 0; - in += fill; - inlen -= fill; - } - if (inlen > BLAKE2S_BLOCK_SIZE) { - const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE); - /* Hash one less (full) block than strictly possible */ - blake2s_compress_generic(state, in, nblocks - 1, BLAKE2S_BLOCK_SIZE); - in += BLAKE2S_BLOCK_SIZE * (nblocks - 1); - inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1); +#define BLAKE2S_ALG(name, driver_name, digest_size) \ + { \ + .base.cra_name = name, \ + .base.cra_driver_name = driver_name, \ + .base.cra_priority = 100, \ + .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, \ + .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, \ + .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), \ + .base.cra_module = THIS_MODULE, \ + .digestsize = digest_size, \ + .setkey = crypto_blake2s_setkey, \ + .init = crypto_blake2s_init, \ + .update = crypto_blake2s_update_generic, \ + .final = crypto_blake2s_final_generic, \ + .descsize = sizeof(struct blake2s_state), \ } - memcpy(state->buf + state->buflen, in, inlen); - state->buflen += inlen; - - return 0; -} - -static int crypto_blake2s_final(struct shash_desc *desc, u8 *out) -{ - struct blake2s_state *state = shash_desc_ctx(desc); - - blake2s_set_lastblock(state); - memset(state->buf + state->buflen, 0, - BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */ - blake2s_compress_generic(state, state->buf, 1, state->buflen); - cpu_to_le32_array(state->h, ARRAY_SIZE(state->h)); - memcpy(out, state->h, state->outlen); - memzero_explicit(state, sizeof(*state)); - - return 0; -} - -static struct shash_alg blake2s_algs[] = {{ - .base.cra_name = "blake2s-128", - .base.cra_driver_name = "blake2s-128-generic", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_128_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}, { - .base.cra_name = "blake2s-160", - .base.cra_driver_name = "blake2s-160-generic", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_160_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}, { - .base.cra_name = "blake2s-224", - .base.cra_driver_name = "blake2s-224-generic", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - - .digestsize = BLAKE2S_224_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}, { - .base.cra_name = "blake2s-256", - .base.cra_driver_name = "blake2s-256-generic", - .base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY, - .base.cra_ctxsize = sizeof(struct blake2s_tfm_ctx), - .base.cra_priority = 200, - .base.cra_blocksize = BLAKE2S_BLOCK_SIZE, - .base.cra_module = THIS_MODULE, - .digestsize = BLAKE2S_256_HASH_SIZE, - .setkey = crypto_blake2s_setkey, - .init = crypto_blake2s_init, - .update = crypto_blake2s_update, - .final = crypto_blake2s_final, - .descsize = sizeof(struct blake2s_state), -}}; +static struct shash_alg blake2s_algs[] = { + BLAKE2S_ALG("blake2s-128", "blake2s-128-generic", + BLAKE2S_128_HASH_SIZE), + BLAKE2S_ALG("blake2s-160", "blake2s-160-generic", + BLAKE2S_160_HASH_SIZE), + BLAKE2S_ALG("blake2s-224", "blake2s-224-generic", + BLAKE2S_224_HASH_SIZE), + BLAKE2S_ALG("blake2s-256", "blake2s-256-generic", + BLAKE2S_256_HASH_SIZE), +}; static int __init blake2s_mod_init(void) { diff --git a/crypto/drbg.c b/crypto/drbg.c index 3132967a17497..19ea8d6628ffb 100644 --- a/crypto/drbg.c +++ b/crypto/drbg.c @@ -1490,12 +1490,13 @@ static int drbg_generate_long(struct drbg_state *drbg, return 0; } -static void drbg_schedule_async_seed(struct random_ready_callback *rdy) +static int drbg_schedule_async_seed(struct notifier_block *nb, unsigned long action, void *data) { - struct drbg_state *drbg = container_of(rdy, struct drbg_state, + struct drbg_state *drbg = container_of(nb, struct drbg_state, random_ready); schedule_work(&drbg->seed_work); + return 0; } static int drbg_prepare_hrng(struct drbg_state *drbg) @@ -1510,10 +1511,8 @@ static int drbg_prepare_hrng(struct drbg_state *drbg) INIT_WORK(&drbg->seed_work, drbg_async_seed); - drbg->random_ready.owner = THIS_MODULE; - drbg->random_ready.func = drbg_schedule_async_seed; - - err = add_random_ready_callback(&drbg->random_ready); + drbg->random_ready.notifier_call = drbg_schedule_async_seed; + err = register_random_ready_notifier(&drbg->random_ready); switch (err) { case 0: @@ -1524,7 +1523,7 @@ static int drbg_prepare_hrng(struct drbg_state *drbg) fallthrough; default: - drbg->random_ready.func = NULL; + drbg->random_ready.notifier_call = NULL; return err; } @@ -1628,8 +1627,8 @@ free_everything: */ static int drbg_uninstantiate(struct drbg_state *drbg) { - if (drbg->random_ready.func) { - del_random_ready_callback(&drbg->random_ready); + if (drbg->random_ready.notifier_call) { + unregister_random_ready_notifier(&drbg->random_ready); cancel_work_sync(&drbg->seed_work); } diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c index a5cc4f3bb1e31..1d94c4625f365 100644 --- a/drivers/acpi/sysfs.c +++ b/drivers/acpi/sysfs.c @@ -439,18 +439,29 @@ static ssize_t acpi_data_show(struct file *filp, struct kobject *kobj, { struct acpi_data_attr *data_attr; void __iomem *base; - ssize_t rc; + ssize_t size; data_attr = container_of(bin_attr, struct acpi_data_attr, attr); + size = data_attr->attr.size; + + if (offset < 0) + return -EINVAL; + + if (offset >= size) + return 0; - base = acpi_os_map_memory(data_attr->addr, data_attr->attr.size); + if (count > size - offset) + count = size - offset; + + base = acpi_os_map_iomem(data_attr->addr, size); if (!base) return -ENOMEM; - rc = memory_read_from_buffer(buf, count, &offset, base, - data_attr->attr.size); - acpi_os_unmap_memory(base, data_attr->attr.size); - return rc; + memcpy_fromio(buf, base + offset, count); + + acpi_os_unmap_iomem(base, size); + + return count; } static int acpi_bert_data_init(void *th, struct acpi_data_attr *data_attr) diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig index d229a2d0c0174..3e2703a496328 100644 --- a/drivers/char/Kconfig +++ b/drivers/char/Kconfig @@ -495,4 +495,5 @@ config RANDOM_TRUST_BOOTLOADER device randomness. Say Y here to assume the entropy provided by the booloader is trustworthy so it will be added to the kernel's entropy pool. Otherwise, say N here so it will be regarded as device input that - only mixes the entropy pool. + only mixes the entropy pool. This can also be configured at boot with + "random.trust_bootloader=on/off". diff --git a/drivers/char/hw_random/core.c b/drivers/char/hw_random/core.c index 8c1c47dd9f464..5749998feaa46 100644 --- a/drivers/char/hw_random/core.c +++ b/drivers/char/hw_random/core.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include diff --git a/drivers/char/random.c b/drivers/char/random.c index 5f541c9465598..00b50ccc9fae6 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -1,310 +1,26 @@ +// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause) /* - * random.c -- A strong random number generator - * - * Copyright (C) 2017 Jason A. Donenfeld . All - * Rights Reserved. - * + * Copyright (C) 2017-2022 Jason A. Donenfeld . All Rights Reserved. * Copyright Matt Mackall , 2003, 2004, 2005 - * - * Copyright Theodore Ts'o, 1994, 1995, 1996, 1997, 1998, 1999. All - * rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, and the entire permission notice in its entirety, - * including the disclaimer of warranties. - * 2. Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * 3. The name of the author may not be used to endorse or promote - * products derived from this software without specific prior - * written permission. - * - * ALTERNATIVELY, this product may be distributed under the terms of - * the GNU General Public License, in which case the provisions of the GPL are - * required INSTEAD OF the above restrictions. (This clause is - * necessary due to a potential bad interaction between the GPL and - * the restrictions contained in a BSD-style copyright.) - * - * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED - * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES - * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ALL OF - * WHICH ARE HEREBY DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE - * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR - * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT - * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR - * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF - * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE - * USE OF THIS SOFTWARE, EVEN IF NOT ADVISED OF THE POSSIBILITY OF SUCH - * DAMAGE. - */ - -/* - * (now, with legal B.S. out of the way.....) - * - * This routine gathers environmental noise from device drivers, etc., - * and returns good random numbers, suitable for cryptographic use. - * Besides the obvious cryptographic uses, these numbers are also good - * for seeding TCP sequence numbers, and other places where it is - * desirable to have numbers which are not only random, but hard to - * predict by an attacker. - * - * Theory of operation - * =================== - * - * Computers are very predictable devices. Hence it is extremely hard - * to produce truly random numbers on a computer --- as opposed to - * pseudo-random numbers, which can easily generated by using a - * algorithm. Unfortunately, it is very easy for attackers to guess - * the sequence of pseudo-random number generators, and for some - * applications this is not acceptable. So instead, we must try to - * gather "environmental noise" from the computer's environment, which - * must be hard for outside attackers to observe, and use that to - * generate random numbers. In a Unix environment, this is best done - * from inside the kernel. - * - * Sources of randomness from the environment include inter-keyboard - * timings, inter-interrupt timings from some interrupts, and other - * events which are both (a) non-deterministic and (b) hard for an - * outside observer to measure. Randomness from these sources are - * added to an "entropy pool", which is mixed using a CRC-like function. - * This is not cryptographically strong, but it is adequate assuming - * the randomness is not chosen maliciously, and it is fast enough that - * the overhead of doing it on every interrupt is very reasonable. - * As random bytes are mixed into the entropy pool, the routines keep - * an *estimate* of how many bits of randomness have been stored into - * the random number generator's internal state. - * - * When random bytes are desired, they are obtained by taking the SHA - * hash of the contents of the "entropy pool". The SHA hash avoids - * exposing the internal state of the entropy pool. It is believed to - * be computationally infeasible to derive any useful information - * about the input of SHA from its output. Even if it is possible to - * analyze SHA in some clever way, as long as the amount of data - * returned from the generator is less than the inherent entropy in - * the pool, the output data is totally unpredictable. For this - * reason, the routine decreases its internal estimate of how many - * bits of "true randomness" are contained in the entropy pool as it - * outputs random numbers. - * - * If this estimate goes to zero, the routine can still generate - * random numbers; however, an attacker may (at least in theory) be - * able to infer the future output of the generator from prior - * outputs. This requires successful cryptanalysis of SHA, which is - * not believed to be feasible, but there is a remote possibility. - * Nonetheless, these numbers should be useful for the vast majority - * of purposes. - * - * Exported interfaces ---- output - * =============================== - * - * There are four exported interfaces; two for use within the kernel, - * and two or use from userspace. - * - * Exported interfaces ---- userspace output - * ----------------------------------------- - * - * The userspace interfaces are two character devices /dev/random and - * /dev/urandom. /dev/random is suitable for use when very high - * quality randomness is desired (for example, for key generation or - * one-time pads), as it will only return a maximum of the number of - * bits of randomness (as estimated by the random number generator) - * contained in the entropy pool. - * - * The /dev/urandom device does not have this limit, and will return - * as many bytes as are requested. As more and more random bytes are - * requested without giving time for the entropy pool to recharge, - * this will result in random numbers that are merely cryptographically - * strong. For many applications, however, this is acceptable. - * - * Exported interfaces ---- kernel output - * -------------------------------------- - * - * The primary kernel interface is - * - * void get_random_bytes(void *buf, int nbytes); - * - * This interface will return the requested number of random bytes, - * and place it in the requested buffer. This is equivalent to a - * read from /dev/urandom. - * - * For less critical applications, there are the functions: - * - * u32 get_random_u32() - * u64 get_random_u64() - * unsigned int get_random_int() - * unsigned long get_random_long() - * - * These are produced by a cryptographic RNG seeded from get_random_bytes, - * and so do not deplete the entropy pool as much. These are recommended - * for most in-kernel operations *if the result is going to be stored in - * the kernel*. - * - * Specifically, the get_random_int() family do not attempt to do - * "anti-backtracking". If you capture the state of the kernel (e.g. - * by snapshotting the VM), you can figure out previous get_random_int() - * return values. But if the value is stored in the kernel anyway, - * this is not a problem. - * - * It *is* safe to expose get_random_int() output to attackers (e.g. as - * network cookies); given outputs 1..n, it's not feasible to predict - * outputs 0 or n+1. The only concern is an attacker who breaks into - * the kernel later; the get_random_int() engine is not reseeded as - * often as the get_random_bytes() one. - * - * get_random_bytes() is needed for keys that need to stay secret after - * they are erased from the kernel. For example, any key that will - * be wrapped and stored encrypted. And session encryption keys: we'd - * like to know that after the session is closed and the keys erased, - * the plaintext is unrecoverable to someone who recorded the ciphertext. - * - * But for network ports/cookies, stack canaries, PRNG seeds, address - * space layout randomization, session *authentication* keys, or other - * applications where the sensitive data is stored in the kernel in - * plaintext for as long as it's sensitive, the get_random_int() family - * is just fine. - * - * Consider ASLR. We want to keep the address space secret from an - * outside attacker while the process is running, but once the address - * space is torn down, it's of no use to an attacker any more. And it's - * stored in kernel data structures as long as it's alive, so worrying - * about an attacker's ability to extrapolate it from the get_random_int() - * CRNG is silly. - * - * Even some cryptographic keys are safe to generate with get_random_int(). - * In particular, keys for SipHash are generally fine. Here, knowledge - * of the key authorizes you to do something to a kernel object (inject - * packets to a network connection, or flood a hash table), and the - * key is stored with the object being protected. Once it goes away, - * we no longer care if anyone knows the key. - * - * prandom_u32() - * ------------- - * - * For even weaker applications, see the pseudorandom generator - * prandom_u32(), prandom_max(), and prandom_bytes(). If the random - * numbers aren't security-critical at all, these are *far* cheaper. - * Useful for self-tests, random error simulation, randomized backoffs, - * and any other application where you trust that nobody is trying to - * maliciously mess with you by guessing the "random" numbers. - * - * Exported interfaces ---- input - * ============================== - * - * The current exported interfaces for gathering environmental noise - * from the devices are: - * - * void add_device_randomness(const void *buf, unsigned int size); - * void add_input_randomness(unsigned int type, unsigned int code, - * unsigned int value); - * void add_interrupt_randomness(int irq, int irq_flags); - * void add_disk_randomness(struct gendisk *disk); - * - * add_device_randomness() is for adding data to the random pool that - * is likely to differ between two devices (or possibly even per boot). - * This would be things like MAC addresses or serial numbers, or the - * read-out of the RTC. This does *not* add any actual entropy to the - * pool, but it initializes the pool to different values for devices - * that might otherwise be identical and have very little entropy - * available to them (particularly common in the embedded world). - * - * add_input_randomness() uses the input layer interrupt timing, as well as - * the event type information from the hardware. - * - * add_interrupt_randomness() uses the interrupt timing as random - * inputs to the entropy pool. Using the cycle counters and the irq source - * as inputs, it feeds the randomness roughly once a second. - * - * add_disk_randomness() uses what amounts to the seek time of block - * layer request events, on a per-disk_devt basis, as input to the - * entropy pool. Note that high-speed solid state drives with very low - * seek times do not make for good sources of entropy, as their seek - * times are usually fairly consistent. - * - * All of these routines try to estimate how many bits of randomness a - * particular randomness source. They do this by keeping track of the - * first and second order deltas of the event timings. - * - * Ensuring unpredictability at system startup - * ============================================ - * - * When any operating system starts up, it will go through a sequence - * of actions that are fairly predictable by an adversary, especially - * if the start-up does not involve interaction with a human operator. - * This reduces the actual number of bits of unpredictability in the - * entropy pool below the value in entropy_count. In order to - * counteract this effect, it helps to carry information in the - * entropy pool across shut-downs and start-ups. To do this, put the - * following lines an appropriate script which is run during the boot - * sequence: - * - * echo "Initializing random number generator..." - * random_seed=/var/run/random-seed - * # Carry a random seed from start-up to start-up - * # Load and then save the whole entropy pool - * if [ -f $random_seed ]; then - * cat $random_seed >/dev/urandom - * else - * touch $random_seed - * fi - * chmod 600 $random_seed - * dd if=/dev/urandom of=$random_seed count=1 bs=512 - * - * and the following lines in an appropriate script which is run as - * the system is shutdown: - * - * # Carry a random seed from shut-down to start-up - * # Save the whole entropy pool - * echo "Saving random seed..." - * random_seed=/var/run/random-seed - * touch $random_seed - * chmod 600 $random_seed - * dd if=/dev/urandom of=$random_seed count=1 bs=512 - * - * For example, on most modern systems using the System V init - * scripts, such code fragments would be found in - * /etc/rc.d/init.d/random. On older Linux systems, the correct script - * location might be in /etc/rcb.d/rc.local or /etc/rc.d/rc.0. - * - * Effectively, these commands cause the contents of the entropy pool - * to be saved at shut-down time and reloaded into the entropy pool at - * start-up. (The 'dd' in the addition to the bootup script is to - * make sure that /etc/random-seed is different for every start-up, - * even if the system crashes without executing rc.0.) Even with - * complete knowledge of the start-up activities, predicting the state - * of the entropy pool requires knowledge of the previous history of - * the system. - * - * Configuring the /dev/random driver under Linux - * ============================================== - * - * The /dev/random driver under Linux uses minor numbers 8 and 9 of - * the /dev/mem major number (#1). So if your system does not have - * /dev/random and /dev/urandom created already, they can be created - * by using the commands: - * - * mknod /dev/random c 1 8 - * mknod /dev/urandom c 1 9 - * - * Acknowledgements: - * ================= - * - * Ideas for constructing this random number generator were derived - * from Pretty Good Privacy's random number generator, and from private - * discussions with Phil Karn. Colin Plumb provided a faster random - * number generator, which speed up the mixing function of the entropy - * pool, taken from PGPfone. Dale Worley has also contributed many - * useful ideas and suggestions to improve this driver. - * - * Any flaws in the design are solely my responsibility, and should - * not be attributed to the Phil, Colin, or any of authors of PGP. - * - * Further background information on this topic may be obtained from - * RFC 1750, "Randomness Recommendations for Security", by Donald - * Eastlake, Steve Crocker, and Jeff Schiller. + * Copyright Theodore Ts'o, 1994, 1995, 1996, 1997, 1998, 1999. All rights reserved. + * + * This driver produces cryptographically secure pseudorandom data. It is divided + * into roughly six sections, each with a section header: + * + * - Initialization and readiness waiting. + * - Fast key erasure RNG, the "crng". + * - Entropy accumulation and extraction routines. + * - Entropy collection routines. + * - Userspace reader/writer interfaces. + * - Sysctl interface. + * + * The high level overview is that there is one input pool, into which + * various pieces of data are hashed. Prior to initialization, some of that + * data is then "credited" as having a certain number of bits of entropy. + * When enough bits of entropy are available, the hash is finalized and + * handed as a key to a stream cipher that expands it indefinitely for + * various consumers. This key is periodically refreshed as the various + * entropy collectors, described below, add data to the input pool. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt @@ -327,7 +43,6 @@ #include #include #include -#include #include #include #include @@ -335,1503 +50,1082 @@ #include #include #include +#include +#include +#include #include -#include - +#include #include -#include #include #include #include -#define CREATE_TRACE_POINTS -#include - -/* #define ADD_INTERRUPT_BENCH */ +/********************************************************************* + * + * Initialization and readiness waiting. + * + * Much of the RNG infrastructure is devoted to various dependencies + * being able to wait until the RNG has collected enough entropy and + * is ready for safe consumption. + * + *********************************************************************/ /* - * Configuration information + * crng_init is protected by base_crng->lock, and only increases + * its value (from empty->early->ready). */ -#define INPUT_POOL_SHIFT 12 -#define INPUT_POOL_WORDS (1 << (INPUT_POOL_SHIFT-5)) -#define OUTPUT_POOL_SHIFT 10 -#define OUTPUT_POOL_WORDS (1 << (OUTPUT_POOL_SHIFT-5)) -#define EXTRACT_SIZE 10 - +static enum { + CRNG_EMPTY = 0, /* Little to no entropy collected */ + CRNG_EARLY = 1, /* At least POOL_EARLY_BITS collected */ + CRNG_READY = 2 /* Fully initialized with POOL_READY_BITS collected */ +} crng_init __read_mostly = CRNG_EMPTY; +static DEFINE_STATIC_KEY_FALSE(crng_is_ready); +#define crng_ready() (static_branch_likely(&crng_is_ready) || crng_init >= CRNG_READY) +/* Various types of waiters for crng_init->CRNG_READY transition. */ +static DECLARE_WAIT_QUEUE_HEAD(crng_init_wait); +static struct fasync_struct *fasync; +static DEFINE_SPINLOCK(random_ready_chain_lock); +static RAW_NOTIFIER_HEAD(random_ready_chain); -#define LONGS(x) (((x) + sizeof(unsigned long) - 1)/sizeof(unsigned long)) +/* Control how we warn userspace. */ +static struct ratelimit_state urandom_warning = + RATELIMIT_STATE_INIT("warn_urandom_randomness", HZ, 3); +static int ratelimit_disable __read_mostly = + IS_ENABLED(CONFIG_WARN_ALL_UNSEEDED_RANDOM); +module_param_named(ratelimit_disable, ratelimit_disable, int, 0644); +MODULE_PARM_DESC(ratelimit_disable, "Disable random ratelimit suppression"); /* - * To allow fractional bits to be tracked, the entropy_count field is - * denominated in units of 1/8th bits. + * Returns whether or not the input pool has been seeded and thus guaranteed + * to supply cryptographically secure random numbers. This applies to: the + * /dev/urandom device, the get_random_bytes function, and the get_random_{u32, + * ,u64,int,long} family of functions. * - * 2*(ENTROPY_SHIFT + poolbitshift) must <= 31, or the multiply in - * credit_entropy_bits() needs to be 64 bits wide. + * Returns: true if the input pool has been seeded. + * false if the input pool has not been seeded. */ -#define ENTROPY_SHIFT 3 -#define ENTROPY_BITS(r) ((r)->entropy_count >> ENTROPY_SHIFT) +bool rng_is_initialized(void) +{ + return crng_ready(); +} +EXPORT_SYMBOL(rng_is_initialized); -/* - * If the entropy count falls under this number of bits, then we - * should wake up processes which are selecting or polling on write - * access to /dev/random. - */ -static int random_write_wakeup_bits = 28 * OUTPUT_POOL_WORDS; +static void __cold crng_set_ready(struct work_struct *work) +{ + static_branch_enable(&crng_is_ready); +} + +/* Used by wait_for_random_bytes(), and considered an entropy collector, below. */ +static void try_to_generate_entropy(void); /* - * Originally, we used a primitive polynomial of degree .poolwords - * over GF(2). The taps for various sizes are defined below. They - * were chosen to be evenly spaced except for the last tap, which is 1 - * to get the twisting happening as fast as possible. - * - * For the purposes of better mixing, we use the CRC-32 polynomial as - * well to make a (modified) twisted Generalized Feedback Shift - * Register. (See M. Matsumoto & Y. Kurita, 1992. Twisted GFSR - * generators. ACM Transactions on Modeling and Computer Simulation - * 2(3):179-194. Also see M. Matsumoto & Y. Kurita, 1994. Twisted - * GFSR generators II. ACM Transactions on Modeling and Computer - * Simulation 4:254-266) - * - * Thanks to Colin Plumb for suggesting this. - * - * The mixing operation is much less sensitive than the output hash, - * where we use SHA-1. All that we want of mixing operation is that - * it be a good non-cryptographic hash; i.e. it not produce collisions - * when fed "random" data of the sort we expect to see. As long as - * the pool state differs for different inputs, we have preserved the - * input entropy and done a good job. The fact that an intelligent - * attacker can construct inputs that will produce controlled - * alterations to the pool's state is not important because we don't - * consider such inputs to contribute any randomness. The only - * property we need with respect to them is that the attacker can't - * increase his/her knowledge of the pool's state. Since all - * additions are reversible (knowing the final state and the input, - * you can reconstruct the initial state), if an attacker has any - * uncertainty about the initial state, he/she can only shuffle that - * uncertainty about, but never cause any collisions (which would - * decrease the uncertainty). + * Wait for the input pool to be seeded and thus guaranteed to supply + * cryptographically secure random numbers. This applies to: the /dev/urandom + * device, the get_random_bytes function, and the get_random_{u32,u64,int,long} + * family of functions. Using any of these functions without first calling + * this function forfeits the guarantee of security. * - * Our mixing functions were analyzed by Lacharme, Roeck, Strubel, and - * Videau in their paper, "The Linux Pseudorandom Number Generator - * Revisited" (see: http://eprint.iacr.org/2012/251.pdf). In their - * paper, they point out that we are not using a true Twisted GFSR, - * since Matsumoto & Kurita used a trinomial feedback polynomial (that - * is, with only three taps, instead of the six that we are using). - * As a result, the resulting polynomial is neither primitive nor - * irreducible, and hence does not have a maximal period over - * GF(2**32). They suggest a slight change to the generator - * polynomial which improves the resulting TGFSR polynomial to be - * irreducible, which we have made here. + * Returns: 0 if the input pool has been seeded. + * -ERESTARTSYS if the function was interrupted by a signal. */ -static const struct poolinfo { - int poolbitshift, poolwords, poolbytes, poolfracbits; -#define S(x) ilog2(x)+5, (x), (x)*4, (x) << (ENTROPY_SHIFT+5) - int tap1, tap2, tap3, tap4, tap5; -} poolinfo_table[] = { - /* was: x^128 + x^103 + x^76 + x^51 +x^25 + x + 1 */ - /* x^128 + x^104 + x^76 + x^51 +x^25 + x + 1 */ - { S(128), 104, 76, 51, 25, 1 }, -}; +int wait_for_random_bytes(void) +{ + while (!crng_ready()) { + int ret; + + try_to_generate_entropy(); + ret = wait_event_interruptible_timeout(crng_init_wait, crng_ready(), HZ); + if (ret) + return ret > 0 ? 0 : ret; + } + return 0; +} +EXPORT_SYMBOL(wait_for_random_bytes); /* - * Static global variables + * Add a callback function that will be invoked when the input + * pool is initialised. + * + * returns: 0 if callback is successfully added + * -EALREADY if pool is already initialised (callback not called) */ -static DECLARE_WAIT_QUEUE_HEAD(random_write_wait); -static struct fasync_struct *fasync; - -static DEFINE_SPINLOCK(random_ready_list_lock); -static LIST_HEAD(random_ready_list); +int __cold register_random_ready_notifier(struct notifier_block *nb) +{ + unsigned long flags; + int ret = -EALREADY; -struct crng_state { - __u32 state[16]; - unsigned long init_time; - spinlock_t lock; -}; + if (crng_ready()) + return ret; -static struct crng_state primary_crng = { - .lock = __SPIN_LOCK_UNLOCKED(primary_crng.lock), -}; + spin_lock_irqsave(&random_ready_chain_lock, flags); + if (!crng_ready()) + ret = raw_notifier_chain_register(&random_ready_chain, nb); + spin_unlock_irqrestore(&random_ready_chain_lock, flags); + return ret; +} +EXPORT_SYMBOL(register_random_ready_notifier); /* - * crng_init = 0 --> Uninitialized - * 1 --> Initialized - * 2 --> Initialized from input_pool - * - * crng_init is protected by primary_crng->lock, and only increases - * its value (from 0->1->2). + * Delete a previously registered readiness callback function. */ -static int crng_init = 0; -static bool crng_need_final_init = false; -#define crng_ready() (likely(crng_init > 1)) -static int crng_init_cnt = 0; -static unsigned long crng_global_init_time = 0; -#define CRNG_INIT_CNT_THRESH (2*CHACHA_KEY_SIZE) -static void _extract_crng(struct crng_state *crng, __u8 out[CHACHA_BLOCK_SIZE]); -static void _crng_backtrack_protect(struct crng_state *crng, - __u8 tmp[CHACHA_BLOCK_SIZE], int used); -static void process_random_ready_list(void); -static void _get_random_bytes(void *buf, int nbytes); - -static struct ratelimit_state unseeded_warning = - RATELIMIT_STATE_INIT("warn_unseeded_randomness", HZ, 3); -static struct ratelimit_state urandom_warning = - RATELIMIT_STATE_INIT("warn_urandom_randomness", HZ, 3); +int __cold unregister_random_ready_notifier(struct notifier_block *nb) +{ + unsigned long flags; + int ret; -static int ratelimit_disable __read_mostly; + spin_lock_irqsave(&random_ready_chain_lock, flags); + ret = raw_notifier_chain_unregister(&random_ready_chain, nb); + spin_unlock_irqrestore(&random_ready_chain_lock, flags); + return ret; +} +EXPORT_SYMBOL(unregister_random_ready_notifier); -module_param_named(ratelimit_disable, ratelimit_disable, int, 0644); -MODULE_PARM_DESC(ratelimit_disable, "Disable random ratelimit suppression"); +static void __cold process_random_ready_list(void) +{ + unsigned long flags; -/********************************************************************** + spin_lock_irqsave(&random_ready_chain_lock, flags); + raw_notifier_call_chain(&random_ready_chain, 0, NULL); + spin_unlock_irqrestore(&random_ready_chain_lock, flags); +} + +#define warn_unseeded_randomness() \ + if (IS_ENABLED(CONFIG_WARN_ALL_UNSEEDED_RANDOM) && !crng_ready()) \ + printk_deferred(KERN_NOTICE "random: %s called from %pS with crng_init=%d\n", \ + __func__, (void *)_RET_IP_, crng_init) + + +/********************************************************************* * - * OS independent entropy store. Here are the functions which handle - * storing entropy in an entropy pool. + * Fast key erasure RNG, the "crng". * - **********************************************************************/ + * These functions expand entropy from the entropy extractor into + * long streams for external consumption using the "fast key erasure" + * RNG described at . + * + * There are a few exported interfaces for use by other drivers: + * + * void get_random_bytes(void *buf, size_t len) + * u32 get_random_u32() + * u64 get_random_u64() + * unsigned int get_random_int() + * unsigned long get_random_long() + * + * These interfaces will return the requested number of random bytes + * into the given buffer or as a return value. This is equivalent to + * a read from /dev/urandom. The u32, u64, int, and long family of + * functions may be higher performance for one-off random integers, + * because they do a bit of buffering and do not invoke reseeding + * until the buffer is emptied. + * + *********************************************************************/ -struct entropy_store; -struct entropy_store { - /* read-only data: */ - const struct poolinfo *poolinfo; - __u32 *pool; - const char *name; +enum { + CRNG_RESEED_START_INTERVAL = HZ, + CRNG_RESEED_INTERVAL = 60 * HZ +}; - /* read-write data: */ +static struct { + u8 key[CHACHA_KEY_SIZE] __aligned(__alignof__(long)); + unsigned long birth; + unsigned long generation; spinlock_t lock; - unsigned short add_ptr; - unsigned short input_rotate; - int entropy_count; - unsigned int initialized:1; - unsigned int last_data_init:1; - __u8 last_data[EXTRACT_SIZE]; +} base_crng = { + .lock = __SPIN_LOCK_UNLOCKED(base_crng.lock) }; -static ssize_t extract_entropy(struct entropy_store *r, void *buf, - size_t nbytes, int min, int rsvd); -static ssize_t _extract_entropy(struct entropy_store *r, void *buf, - size_t nbytes, int fips); - -static void crng_reseed(struct crng_state *crng, struct entropy_store *r); -static __u32 input_pool_data[INPUT_POOL_WORDS] __latent_entropy; - -static struct entropy_store input_pool = { - .poolinfo = &poolinfo_table[0], - .name = "input", - .lock = __SPIN_LOCK_UNLOCKED(input_pool.lock), - .pool = input_pool_data +struct crng { + u8 key[CHACHA_KEY_SIZE]; + unsigned long generation; + local_lock_t lock; }; -static __u32 const twist_table[8] = { - 0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158, - 0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278 }; - -/* - * This function adds bytes into the entropy "pool". It does not - * update the entropy estimate. The caller should call - * credit_entropy_bits if this is appropriate. - * - * The pool is stirred with a primitive polynomial of the appropriate - * degree, and then twisted. We twist by three bits at a time because - * it's cheap to do so and helps slightly in the expected case where - * the entropy is concentrated in the low-order bits. - */ -static void _mix_pool_bytes(struct entropy_store *r, const void *in, - int nbytes) -{ - unsigned long i, tap1, tap2, tap3, tap4, tap5; - int input_rotate; - int wordmask = r->poolinfo->poolwords - 1; - const char *bytes = in; - __u32 w; - - tap1 = r->poolinfo->tap1; - tap2 = r->poolinfo->tap2; - tap3 = r->poolinfo->tap3; - tap4 = r->poolinfo->tap4; - tap5 = r->poolinfo->tap5; - - input_rotate = r->input_rotate; - i = r->add_ptr; - - /* mix one byte at a time to simplify size handling and churn faster */ - while (nbytes--) { - w = rol32(*bytes++, input_rotate); - i = (i - 1) & wordmask; - - /* XOR in the various taps */ - w ^= r->pool[i]; - w ^= r->pool[(i + tap1) & wordmask]; - w ^= r->pool[(i + tap2) & wordmask]; - w ^= r->pool[(i + tap3) & wordmask]; - w ^= r->pool[(i + tap4) & wordmask]; - w ^= r->pool[(i + tap5) & wordmask]; - - /* Mix the result back in with a twist */ - r->pool[i] = (w >> 3) ^ twist_table[w & 7]; - - /* - * Normally, we add 7 bits of rotation to the pool. - * At the beginning of the pool, add an extra 7 bits - * rotation, so that successive passes spread the - * input bits across the pool evenly. - */ - input_rotate = (input_rotate + (i ? 7 : 14)) & 31; - } - - r->input_rotate = input_rotate; - r->add_ptr = i; -} +static DEFINE_PER_CPU(struct crng, crngs) = { + .generation = ULONG_MAX, + .lock = INIT_LOCAL_LOCK(crngs.lock), +}; -static void __mix_pool_bytes(struct entropy_store *r, const void *in, - int nbytes) -{ - trace_mix_pool_bytes_nolock(r->name, nbytes, _RET_IP_); - _mix_pool_bytes(r, in, nbytes); -} +/* Used by crng_reseed() and crng_make_state() to extract a new seed from the input pool. */ +static void extract_entropy(void *buf, size_t len); -static void mix_pool_bytes(struct entropy_store *r, const void *in, - int nbytes) +/* This extracts a new crng key from the input pool. */ +static void crng_reseed(void) { unsigned long flags; + unsigned long next_gen; + u8 key[CHACHA_KEY_SIZE]; - trace_mix_pool_bytes(r->name, nbytes, _RET_IP_); - spin_lock_irqsave(&r->lock, flags); - _mix_pool_bytes(r, in, nbytes); - spin_unlock_irqrestore(&r->lock, flags); -} + extract_entropy(key, sizeof(key)); -struct fast_pool { - __u32 pool[4]; - unsigned long last; - unsigned short reg_idx; - unsigned char count; -}; + /* + * We copy the new key into the base_crng, overwriting the old one, + * and update the generation counter. We avoid hitting ULONG_MAX, + * because the per-cpu crngs are initialized to ULONG_MAX, so this + * forces new CPUs that come online to always initialize. + */ + spin_lock_irqsave(&base_crng.lock, flags); + memcpy(base_crng.key, key, sizeof(base_crng.key)); + next_gen = base_crng.generation + 1; + if (next_gen == ULONG_MAX) + ++next_gen; + WRITE_ONCE(base_crng.generation, next_gen); + WRITE_ONCE(base_crng.birth, jiffies); + if (!static_branch_likely(&crng_is_ready)) + crng_init = CRNG_READY; + spin_unlock_irqrestore(&base_crng.lock, flags); + memzero_explicit(key, sizeof(key)); +} /* - * This is a fast mixing routine used by the interrupt randomness - * collector. It's hardcoded for an 128 bit pool and assumes that any - * locks that might be needed are taken by the caller. + * This generates a ChaCha block using the provided key, and then + * immediately overwites that key with half the block. It returns + * the resultant ChaCha state to the user, along with the second + * half of the block containing 32 bytes of random data that may + * be used; random_data_len may not be greater than 32. + * + * The returned ChaCha state contains within it a copy of the old + * key value, at index 4, so the state should always be zeroed out + * immediately after using in order to maintain forward secrecy. + * If the state cannot be erased in a timely manner, then it is + * safer to set the random_data parameter to &chacha_state[4] so + * that this function overwrites it before returning. */ -static void fast_mix(struct fast_pool *f) +static void crng_fast_key_erasure(u8 key[CHACHA_KEY_SIZE], + u32 chacha_state[CHACHA_STATE_WORDS], + u8 *random_data, size_t random_data_len) { - __u32 a = f->pool[0], b = f->pool[1]; - __u32 c = f->pool[2], d = f->pool[3]; - - a += b; c += d; - b = rol32(b, 6); d = rol32(d, 27); - d ^= a; b ^= c; + u8 first_block[CHACHA_BLOCK_SIZE]; - a += b; c += d; - b = rol32(b, 16); d = rol32(d, 14); - d ^= a; b ^= c; + BUG_ON(random_data_len > 32); - a += b; c += d; - b = rol32(b, 6); d = rol32(d, 27); - d ^= a; b ^= c; + chacha_init_consts(chacha_state); + memcpy(&chacha_state[4], key, CHACHA_KEY_SIZE); + memset(&chacha_state[12], 0, sizeof(u32) * 4); + chacha20_block(chacha_state, first_block); - a += b; c += d; - b = rol32(b, 16); d = rol32(d, 14); - d ^= a; b ^= c; - - f->pool[0] = a; f->pool[1] = b; - f->pool[2] = c; f->pool[3] = d; - f->count++; + memcpy(key, first_block, CHACHA_KEY_SIZE); + memcpy(random_data, first_block + CHACHA_KEY_SIZE, random_data_len); + memzero_explicit(first_block, sizeof(first_block)); } -static void process_random_ready_list(void) -{ - unsigned long flags; - struct random_ready_callback *rdy, *tmp; - - spin_lock_irqsave(&random_ready_list_lock, flags); - list_for_each_entry_safe(rdy, tmp, &random_ready_list, list) { - struct module *owner = rdy->owner; - - list_del_init(&rdy->list); - rdy->func(rdy); - module_put(owner); +/* + * Return whether the crng seed is considered to be sufficiently old + * that a reseeding is needed. This happens if the last reseeding + * was CRNG_RESEED_INTERVAL ago, or during early boot, at an interval + * proportional to the uptime. + */ +static bool crng_has_old_seed(void) +{ + static bool early_boot = true; + unsigned long interval = CRNG_RESEED_INTERVAL; + + if (unlikely(READ_ONCE(early_boot))) { + time64_t uptime = ktime_get_seconds(); + if (uptime >= CRNG_RESEED_INTERVAL / HZ * 2) + WRITE_ONCE(early_boot, false); + else + interval = max_t(unsigned int, CRNG_RESEED_START_INTERVAL, + (unsigned int)uptime / 2 * HZ); } - spin_unlock_irqrestore(&random_ready_list_lock, flags); + return time_is_before_jiffies(READ_ONCE(base_crng.birth) + interval); } /* - * Credit (or debit) the entropy store with n bits of entropy. - * Use credit_entropy_bits_safe() if the value comes from userspace - * or otherwise should be checked for extreme values. + * This function returns a ChaCha state that you may use for generating + * random data. It also returns up to 32 bytes on its own of random data + * that may be used; random_data_len may not be greater than 32. */ -static void credit_entropy_bits(struct entropy_store *r, int nbits) +static void crng_make_state(u32 chacha_state[CHACHA_STATE_WORDS], + u8 *random_data, size_t random_data_len) { - int entropy_count, orig, has_initialized = 0; - const int pool_size = r->poolinfo->poolfracbits; - int nfrac = nbits << ENTROPY_SHIFT; - - if (!nbits) - return; + unsigned long flags; + struct crng *crng; -retry: - entropy_count = orig = READ_ONCE(r->entropy_count); - if (nfrac < 0) { - /* Debit */ - entropy_count += nfrac; - } else { - /* - * Credit: we have to account for the possibility of - * overwriting already present entropy. Even in the - * ideal case of pure Shannon entropy, new contributions - * approach the full value asymptotically: - * - * entropy <- entropy + (pool_size - entropy) * - * (1 - exp(-add_entropy/pool_size)) - * - * For add_entropy <= pool_size/2 then - * (1 - exp(-add_entropy/pool_size)) >= - * (add_entropy/pool_size)*0.7869... - * so we can approximate the exponential with - * 3/4*add_entropy/pool_size and still be on the - * safe side by adding at most pool_size/2 at a time. - * - * The use of pool_size-2 in the while statement is to - * prevent rounding artifacts from making the loop - * arbitrarily long; this limits the loop to log2(pool_size)*2 - * turns no matter how large nbits is. - */ - int pnfrac = nfrac; - const int s = r->poolinfo->poolbitshift + ENTROPY_SHIFT + 2; - /* The +2 corresponds to the /4 in the denominator */ - - do { - unsigned int anfrac = min(pnfrac, pool_size/2); - unsigned int add = - ((pool_size - entropy_count)*anfrac*3) >> s; - - entropy_count += add; - pnfrac -= anfrac; - } while (unlikely(entropy_count < pool_size-2 && pnfrac)); - } + BUG_ON(random_data_len > 32); - if (WARN_ON(entropy_count < 0)) { - pr_warn("negative entropy/overflow: pool %s count %d\n", - r->name, entropy_count); - entropy_count = 0; - } else if (entropy_count > pool_size) - entropy_count = pool_size; - if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig) - goto retry; - - if (has_initialized) { - r->initialized = 1; - kill_fasync(&fasync, SIGIO, POLL_IN); + /* + * For the fast path, we check whether we're ready, unlocked first, and + * then re-check once locked later. In the case where we're really not + * ready, we do fast key erasure with the base_crng directly, extracting + * when crng_init is CRNG_EMPTY. + */ + if (!crng_ready()) { + bool ready; + + spin_lock_irqsave(&base_crng.lock, flags); + ready = crng_ready(); + if (!ready) { + if (crng_init == CRNG_EMPTY) + extract_entropy(base_crng.key, sizeof(base_crng.key)); + crng_fast_key_erasure(base_crng.key, chacha_state, + random_data, random_data_len); + } + spin_unlock_irqrestore(&base_crng.lock, flags); + if (!ready) + return; } - trace_credit_entropy_bits(r->name, nbits, - entropy_count >> ENTROPY_SHIFT, _RET_IP_); + /* + * If the base_crng is old enough, we reseed, which in turn bumps the + * generation counter that we check below. + */ + if (unlikely(crng_has_old_seed())) + crng_reseed(); - if (r == &input_pool) { - int entropy_bits = entropy_count >> ENTROPY_SHIFT; + local_lock_irqsave(&crngs.lock, flags); + crng = raw_cpu_ptr(&crngs); - if (crng_init < 2) { - if (entropy_bits < 128) - return; - crng_reseed(&primary_crng, r); - entropy_bits = ENTROPY_BITS(r); - } + /* + * If our per-cpu crng is older than the base_crng, then it means + * somebody reseeded the base_crng. In that case, we do fast key + * erasure on the base_crng, and use its output as the new key + * for our per-cpu crng. This brings us up to date with base_crng. + */ + if (unlikely(crng->generation != READ_ONCE(base_crng.generation))) { + spin_lock(&base_crng.lock); + crng_fast_key_erasure(base_crng.key, chacha_state, + crng->key, sizeof(crng->key)); + crng->generation = base_crng.generation; + spin_unlock(&base_crng.lock); } + + /* + * Finally, when we've made it this far, our per-cpu crng has an up + * to date key, and we can do fast key erasure with it to produce + * some random data and a ChaCha state for the caller. All other + * branches of this function are "unlikely", so most of the time we + * should wind up here immediately. + */ + crng_fast_key_erasure(crng->key, chacha_state, random_data, random_data_len); + local_unlock_irqrestore(&crngs.lock, flags); } -static int credit_entropy_bits_safe(struct entropy_store *r, int nbits) +static void _get_random_bytes(void *buf, size_t len) { - const int nbits_max = r->poolinfo->poolwords * 32; - - if (nbits < 0) - return -EINVAL; + u32 chacha_state[CHACHA_STATE_WORDS]; + u8 tmp[CHACHA_BLOCK_SIZE]; + size_t first_block_len; - /* Cap the value to avoid overflows */ - nbits = min(nbits, nbits_max); + if (!len) + return; - credit_entropy_bits(r, nbits); - return 0; -} + first_block_len = min_t(size_t, 32, len); + crng_make_state(chacha_state, buf, first_block_len); + len -= first_block_len; + buf += first_block_len; -/********************************************************************* - * - * CRNG using CHACHA20 - * - *********************************************************************/ + while (len) { + if (len < CHACHA_BLOCK_SIZE) { + chacha20_block(chacha_state, tmp); + memcpy(buf, tmp, len); + memzero_explicit(tmp, sizeof(tmp)); + break; + } -#define CRNG_RESEED_INTERVAL (300*HZ) + chacha20_block(chacha_state, buf); + if (unlikely(chacha_state[12] == 0)) + ++chacha_state[13]; + len -= CHACHA_BLOCK_SIZE; + buf += CHACHA_BLOCK_SIZE; + } -static DECLARE_WAIT_QUEUE_HEAD(crng_init_wait); + memzero_explicit(chacha_state, sizeof(chacha_state)); +} -#ifdef CONFIG_NUMA /* - * Hack to deal with crazy userspace progams when they are all trying - * to access /dev/urandom in parallel. The programs are almost - * certainly doing something terribly wrong, but we'll work around - * their brain damage. + * This function is the exported kernel interface. It returns some + * number of good random numbers, suitable for key generation, seeding + * TCP sequence numbers, etc. It does not rely on the hardware random + * number generator. For random bytes direct from the hardware RNG + * (when available), use get_random_bytes_arch(). In order to ensure + * that the randomness provided by this function is okay, the function + * wait_for_random_bytes() should be called and return 0 at least once + * at any point prior. */ -static struct crng_state **crng_node_pool __read_mostly; -#endif - -static void invalidate_batched_entropy(void); -static void numa_crng_init(void); - -static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU); -static int __init parse_trust_cpu(char *arg) +void get_random_bytes(void *buf, size_t len) { - return kstrtobool(arg, &trust_cpu); + warn_unseeded_randomness(); + _get_random_bytes(buf, len); } -early_param("random.trust_cpu", parse_trust_cpu); +EXPORT_SYMBOL(get_random_bytes); -static bool crng_init_try_arch(struct crng_state *crng) +static ssize_t get_random_bytes_user(struct iov_iter *iter) { - int i; - bool arch_init = true; - unsigned long rv; - - for (i = 4; i < 16; i++) { - if (!arch_get_random_seed_long(&rv) && - !arch_get_random_long(&rv)) { - rv = random_get_entropy(); - arch_init = false; - } - crng->state[i] ^= rv; + u32 chacha_state[CHACHA_STATE_WORDS]; + u8 block[CHACHA_BLOCK_SIZE]; + size_t ret = 0, copied; + + if (unlikely(!iov_iter_count(iter))) + return 0; + + /* + * Immediately overwrite the ChaCha key at index 4 with random + * bytes, in case userspace causes copy_to_user() below to sleep + * forever, so that we still retain forward secrecy in that case. + */ + crng_make_state(chacha_state, (u8 *)&chacha_state[4], CHACHA_KEY_SIZE); + /* + * However, if we're doing a read of len <= 32, we don't need to + * use chacha_state after, so we can simply return those bytes to + * the user directly. + */ + if (iov_iter_count(iter) <= CHACHA_KEY_SIZE) { + ret = copy_to_iter(&chacha_state[4], CHACHA_KEY_SIZE, iter); + goto out_zero_chacha; } - return arch_init; -} + for (;;) { + chacha20_block(chacha_state, block); + if (unlikely(chacha_state[12] == 0)) + ++chacha_state[13]; -static bool __init crng_init_try_arch_early(struct crng_state *crng) -{ - int i; - bool arch_init = true; - unsigned long rv; - - for (i = 4; i < 16; i++) { - if (!arch_get_random_seed_long_early(&rv) && - !arch_get_random_long_early(&rv)) { - rv = random_get_entropy(); - arch_init = false; + copied = copy_to_iter(block, sizeof(block), iter); + ret += copied; + if (!iov_iter_count(iter) || copied != sizeof(block)) + break; + + BUILD_BUG_ON(PAGE_SIZE % sizeof(block) != 0); + if (ret % PAGE_SIZE == 0) { + if (signal_pending(current)) + break; + cond_resched(); } - crng->state[i] ^= rv; } - return arch_init; + memzero_explicit(block, sizeof(block)); +out_zero_chacha: + memzero_explicit(chacha_state, sizeof(chacha_state)); + return ret ? ret : -EFAULT; } -static void __maybe_unused crng_initialize_secondary(struct crng_state *crng) -{ - chacha_init_consts(crng->state); - _get_random_bytes(&crng->state[4], sizeof(__u32) * 12); - crng_init_try_arch(crng); - crng->init_time = jiffies - CRNG_RESEED_INTERVAL - 1; -} +/* + * Batched entropy returns random integers. The quality of the random + * number is good as /dev/urandom. In order to ensure that the randomness + * provided by this function is okay, the function wait_for_random_bytes() + * should be called and return 0 at least once at any point prior. + */ -static void __init crng_initialize_primary(struct crng_state *crng) +#define DEFINE_BATCHED_ENTROPY(type) \ +struct batch_ ##type { \ + /* \ + * We make this 1.5x a ChaCha block, so that we get the \ + * remaining 32 bytes from fast key erasure, plus one full \ + * block from the detached ChaCha state. We can increase \ + * the size of this later if needed so long as we keep the \ + * formula of (integer_blocks + 0.5) * CHACHA_BLOCK_SIZE. \ + */ \ + type entropy[CHACHA_BLOCK_SIZE * 3 / (2 * sizeof(type))]; \ + local_lock_t lock; \ + unsigned long generation; \ + unsigned int position; \ +}; \ + \ +static DEFINE_PER_CPU(struct batch_ ##type, batched_entropy_ ##type) = { \ + .lock = INIT_LOCAL_LOCK(batched_entropy_ ##type.lock), \ + .position = UINT_MAX \ +}; \ + \ +type get_random_ ##type(void) \ +{ \ + type ret; \ + unsigned long flags; \ + struct batch_ ##type *batch; \ + unsigned long next_gen; \ + \ + warn_unseeded_randomness(); \ + \ + if (!crng_ready()) { \ + _get_random_bytes(&ret, sizeof(ret)); \ + return ret; \ + } \ + \ + local_lock_irqsave(&batched_entropy_ ##type.lock, flags); \ + batch = raw_cpu_ptr(&batched_entropy_##type); \ + \ + next_gen = READ_ONCE(base_crng.generation); \ + if (batch->position >= ARRAY_SIZE(batch->entropy) || \ + next_gen != batch->generation) { \ + _get_random_bytes(batch->entropy, sizeof(batch->entropy)); \ + batch->position = 0; \ + batch->generation = next_gen; \ + } \ + \ + ret = batch->entropy[batch->position]; \ + batch->entropy[batch->position] = 0; \ + ++batch->position; \ + local_unlock_irqrestore(&batched_entropy_ ##type.lock, flags); \ + return ret; \ +} \ +EXPORT_SYMBOL(get_random_ ##type); + +DEFINE_BATCHED_ENTROPY(u64) +DEFINE_BATCHED_ENTROPY(u32) + +#ifdef CONFIG_SMP +/* + * This function is called when the CPU is coming up, with entry + * CPUHP_RANDOM_PREPARE, which comes before CPUHP_WORKQUEUE_PREP. + */ +int __cold random_prepare_cpu(unsigned int cpu) { - chacha_init_consts(crng->state); - _extract_entropy(&input_pool, &crng->state[4], sizeof(__u32) * 12, 0); - if (crng_init_try_arch_early(crng) && trust_cpu) { - invalidate_batched_entropy(); - numa_crng_init(); - crng_init = 2; - pr_notice("crng done (trusting CPU's manufacturer)\n"); - } - crng->init_time = jiffies - CRNG_RESEED_INTERVAL - 1; -} - -static void crng_finalize_init(struct crng_state *crng) -{ - if (crng != &primary_crng || crng_init >= 2) - return; - if (!system_wq) { - /* We can't call numa_crng_init until we have workqueues, - * so mark this for processing later. */ - crng_need_final_init = true; - return; - } - - invalidate_batched_entropy(); - numa_crng_init(); - crng_init = 2; - process_random_ready_list(); - wake_up_interruptible(&crng_init_wait); - kill_fasync(&fasync, SIGIO, POLL_IN); - pr_notice("crng init done\n"); - if (unseeded_warning.missed) { - pr_notice("%d get_random_xx warning(s) missed due to ratelimiting\n", - unseeded_warning.missed); - unseeded_warning.missed = 0; - } - if (urandom_warning.missed) { - pr_notice("%d urandom warning(s) missed due to ratelimiting\n", - urandom_warning.missed); - urandom_warning.missed = 0; - } -} - -#ifdef CONFIG_NUMA -static void do_numa_crng_init(struct work_struct *work) -{ - int i; - struct crng_state *crng; - struct crng_state **pool; - - pool = kcalloc(nr_node_ids, sizeof(*pool), GFP_KERNEL|__GFP_NOFAIL); - for_each_online_node(i) { - crng = kmalloc_node(sizeof(struct crng_state), - GFP_KERNEL | __GFP_NOFAIL, i); - spin_lock_init(&crng->lock); - crng_initialize_secondary(crng); - pool[i] = crng; - } - /* pairs with READ_ONCE() in select_crng() */ - if (cmpxchg_release(&crng_node_pool, NULL, pool) != NULL) { - for_each_node(i) - kfree(pool[i]); - kfree(pool); - } -} - -static DECLARE_WORK(numa_crng_init_work, do_numa_crng_init); - -static void numa_crng_init(void) -{ - schedule_work(&numa_crng_init_work); -} - -static struct crng_state *select_crng(void) -{ - struct crng_state **pool; - int nid = numa_node_id(); - - /* pairs with cmpxchg_release() in do_numa_crng_init() */ - pool = READ_ONCE(crng_node_pool); - if (pool && pool[nid]) - return pool[nid]; - - return &primary_crng; -} -#else -static void numa_crng_init(void) {} - -static struct crng_state *select_crng(void) -{ - return &primary_crng; + /* + * When the cpu comes back online, immediately invalidate both + * the per-cpu crng and all batches, so that we serve fresh + * randomness. + */ + per_cpu_ptr(&crngs, cpu)->generation = ULONG_MAX; + per_cpu_ptr(&batched_entropy_u32, cpu)->position = UINT_MAX; + per_cpu_ptr(&batched_entropy_u64, cpu)->position = UINT_MAX; + return 0; } #endif /* - * crng_fast_load() can be called by code in the interrupt service - * path. So we can't afford to dilly-dally. Returns the number of - * bytes processed from cp. - */ -static size_t crng_fast_load(const char *cp, size_t len) -{ - unsigned long flags; - char *p; - size_t ret = 0; - - if (!spin_trylock_irqsave(&primary_crng.lock, flags)) - return 0; - if (crng_init != 0) { - spin_unlock_irqrestore(&primary_crng.lock, flags); - return 0; - } - p = (unsigned char *) &primary_crng.state[4]; - while (len > 0 && crng_init_cnt < CRNG_INIT_CNT_THRESH) { - p[crng_init_cnt % CHACHA_KEY_SIZE] ^= *cp; - cp++; crng_init_cnt++; len--; ret++; - } - spin_unlock_irqrestore(&primary_crng.lock, flags); - if (crng_init_cnt >= CRNG_INIT_CNT_THRESH) { - invalidate_batched_entropy(); - crng_init = 1; - pr_notice("fast init done\n"); - } - return ret; -} - -/* - * crng_slow_load() is called by add_device_randomness, which has two - * attributes. (1) We can't trust the buffer passed to it is - * guaranteed to be unpredictable (so it might not have any entropy at - * all), and (2) it doesn't have the performance constraints of - * crng_fast_load(). - * - * So we do something more comprehensive which is guaranteed to touch - * all of the primary_crng's state, and which uses a LFSR with a - * period of 255 as part of the mixing algorithm. Finally, we do - * *not* advance crng_init_cnt since buffer we may get may be something - * like a fixed DMI table (for example), which might very well be - * unique to the machine, but is otherwise unvarying. - */ -static int crng_slow_load(const char *cp, size_t len) -{ - unsigned long flags; - static unsigned char lfsr = 1; - unsigned char tmp; - unsigned i, max = CHACHA_KEY_SIZE; - const char * src_buf = cp; - char * dest_buf = (char *) &primary_crng.state[4]; - - if (!spin_trylock_irqsave(&primary_crng.lock, flags)) - return 0; - if (crng_init != 0) { - spin_unlock_irqrestore(&primary_crng.lock, flags); - return 0; - } - if (len > max) - max = len; - - for (i = 0; i < max ; i++) { - tmp = lfsr; - lfsr >>= 1; - if (tmp & 1) - lfsr ^= 0xE1; - tmp = dest_buf[i % CHACHA_KEY_SIZE]; - dest_buf[i % CHACHA_KEY_SIZE] ^= src_buf[i % len] ^ lfsr; - lfsr += (tmp << 3) | (tmp >> 5); - } - spin_unlock_irqrestore(&primary_crng.lock, flags); - return 1; -} - -static void crng_reseed(struct crng_state *crng, struct entropy_store *r) -{ - unsigned long flags; - int i, num; - union { - __u8 block[CHACHA_BLOCK_SIZE]; - __u32 key[8]; - } buf; - - if (r) { - num = extract_entropy(r, &buf, 32, 16, 0); - if (num == 0) - return; - } else { - _extract_crng(&primary_crng, buf.block); - _crng_backtrack_protect(&primary_crng, buf.block, - CHACHA_KEY_SIZE); - } - spin_lock_irqsave(&crng->lock, flags); - for (i = 0; i < 8; i++) { - unsigned long rv; - if (!arch_get_random_seed_long(&rv) && - !arch_get_random_long(&rv)) - rv = random_get_entropy(); - crng->state[i+4] ^= buf.key[i] ^ rv; - } - memzero_explicit(&buf, sizeof(buf)); - WRITE_ONCE(crng->init_time, jiffies); - spin_unlock_irqrestore(&crng->lock, flags); - crng_finalize_init(crng); -} - -static void _extract_crng(struct crng_state *crng, - __u8 out[CHACHA_BLOCK_SIZE]) -{ - unsigned long v, flags, init_time; - - if (crng_ready()) { - init_time = READ_ONCE(crng->init_time); - if (time_after(READ_ONCE(crng_global_init_time), init_time) || - time_after(jiffies, init_time + CRNG_RESEED_INTERVAL)) - crng_reseed(crng, crng == &primary_crng ? - &input_pool : NULL); - } - spin_lock_irqsave(&crng->lock, flags); - if (arch_get_random_long(&v)) - crng->state[14] ^= v; - chacha20_block(&crng->state[0], out); - if (crng->state[12] == 0) - crng->state[13]++; - spin_unlock_irqrestore(&crng->lock, flags); -} - -static void extract_crng(__u8 out[CHACHA_BLOCK_SIZE]) -{ - _extract_crng(select_crng(), out); -} - -/* - * Use the leftover bytes from the CRNG block output (if there is - * enough) to mutate the CRNG key to provide backtracking protection. + * This function will use the architecture-specific hardware random + * number generator if it is available. It is not recommended for + * use. Use get_random_bytes() instead. It returns the number of + * bytes filled in. */ -static void _crng_backtrack_protect(struct crng_state *crng, - __u8 tmp[CHACHA_BLOCK_SIZE], int used) +size_t __must_check get_random_bytes_arch(void *buf, size_t len) { - unsigned long flags; - __u32 *s, *d; - int i; - - used = round_up(used, sizeof(__u32)); - if (used + CHACHA_KEY_SIZE > CHACHA_BLOCK_SIZE) { - extract_crng(tmp); - used = 0; - } - spin_lock_irqsave(&crng->lock, flags); - s = (__u32 *) &tmp[used]; - d = &crng->state[4]; - for (i=0; i < 8; i++) - *d++ ^= *s++; - spin_unlock_irqrestore(&crng->lock, flags); -} + size_t left = len; + u8 *p = buf; -static void crng_backtrack_protect(__u8 tmp[CHACHA_BLOCK_SIZE], int used) -{ - _crng_backtrack_protect(select_crng(), tmp, used); -} - -static ssize_t extract_crng_user(void __user *buf, size_t nbytes) -{ - ssize_t ret = 0, i = CHACHA_BLOCK_SIZE; - __u8 tmp[CHACHA_BLOCK_SIZE] __aligned(4); - int large_request = (nbytes > 256); - - while (nbytes) { - if (large_request && need_resched()) { - if (signal_pending(current)) { - if (ret == 0) - ret = -ERESTARTSYS; - break; - } - schedule(); - } + while (left) { + unsigned long v; + size_t block_len = min_t(size_t, left, sizeof(unsigned long)); - extract_crng(tmp); - i = min_t(int, nbytes, CHACHA_BLOCK_SIZE); - if (copy_to_user(buf, tmp, i)) { - ret = -EFAULT; + if (!arch_get_random_long(&v)) break; - } - nbytes -= i; - buf += i; - ret += i; + memcpy(p, &v, block_len); + p += block_len; + left -= block_len; } - crng_backtrack_protect(tmp, i); - - /* Wipe data just written to memory */ - memzero_explicit(tmp, sizeof(tmp)); - return ret; + return len - left; } +EXPORT_SYMBOL(get_random_bytes_arch); -/********************************************************************* +/********************************************************************** * - * Entropy input management + * Entropy accumulation and extraction routines. * - *********************************************************************/ + * Callers may add entropy via: + * + * static void mix_pool_bytes(const void *buf, size_t len) + * + * After which, if added entropy should be credited: + * + * static void credit_init_bits(size_t bits) + * + * Finally, extract entropy via: + * + * static void extract_entropy(void *buf, size_t len) + * + **********************************************************************/ -/* There is one of these per entropy source */ -struct timer_rand_state { - cycles_t last_time; - long last_delta, last_delta2; +enum { + POOL_BITS = BLAKE2S_HASH_SIZE * 8, + POOL_READY_BITS = POOL_BITS, /* When crng_init->CRNG_READY */ + POOL_EARLY_BITS = POOL_READY_BITS / 2 /* When crng_init->CRNG_EARLY */ }; -#define INIT_TIMER_RAND_STATE { INITIAL_JIFFIES, }; +static struct { + struct blake2s_state hash; + spinlock_t lock; + unsigned int init_bits; +} input_pool = { + .hash.h = { BLAKE2S_IV0 ^ (0x01010000 | BLAKE2S_HASH_SIZE), + BLAKE2S_IV1, BLAKE2S_IV2, BLAKE2S_IV3, BLAKE2S_IV4, + BLAKE2S_IV5, BLAKE2S_IV6, BLAKE2S_IV7 }, + .hash.outlen = BLAKE2S_HASH_SIZE, + .lock = __SPIN_LOCK_UNLOCKED(input_pool.lock), +}; + +static void _mix_pool_bytes(const void *buf, size_t len) +{ + blake2s_update(&input_pool.hash, buf, len); +} /* - * Add device- or boot-specific data to the input pool to help - * initialize it. - * - * None of this adds any entropy; it is meant to avoid the problem of - * the entropy pool having similar initial state across largely - * identical devices. + * This function adds bytes into the input pool. It does not + * update the initialization bit counter; the caller should call + * credit_init_bits if this is appropriate. */ -void add_device_randomness(const void *buf, unsigned int size) +static void mix_pool_bytes(const void *buf, size_t len) { - unsigned long time = random_get_entropy() ^ jiffies; unsigned long flags; - if (!crng_ready() && size) - crng_slow_load(buf, size); - - trace_add_device_randomness(size, _RET_IP_); spin_lock_irqsave(&input_pool.lock, flags); - _mix_pool_bytes(&input_pool, buf, size); - _mix_pool_bytes(&input_pool, &time, sizeof(time)); + _mix_pool_bytes(buf, len); spin_unlock_irqrestore(&input_pool.lock, flags); } -EXPORT_SYMBOL(add_device_randomness); - -static struct timer_rand_state input_timer_state = INIT_TIMER_RAND_STATE; /* - * This function adds entropy to the entropy "pool" by using timing - * delays. It uses the timer_rand_state structure to make an estimate - * of how many bits of entropy this call has added to the pool. - * - * The number "num" is also added to the pool - it should somehow describe - * the type of event which just happened. This is currently 0-255 for - * keyboard scan codes, and 256 upwards for interrupts. - * + * This is an HKDF-like construction for using the hashed collected entropy + * as a PRF key, that's then expanded block-by-block. */ -static void add_timer_randomness(struct timer_rand_state *state, unsigned num) +static void extract_entropy(void *buf, size_t len) { - struct entropy_store *r; + unsigned long flags; + u8 seed[BLAKE2S_HASH_SIZE], next_key[BLAKE2S_HASH_SIZE]; struct { - long jiffies; - unsigned cycles; - unsigned num; - } sample; - long delta, delta2, delta3; - - sample.jiffies = jiffies; - sample.cycles = random_get_entropy(); - sample.num = num; - r = &input_pool; - mix_pool_bytes(r, &sample, sizeof(sample)); - - /* - * Calculate number of bits of randomness we probably added. - * We take into account the first, second and third-order deltas - * in order to make our estimate. - */ - delta = sample.jiffies - READ_ONCE(state->last_time); - WRITE_ONCE(state->last_time, sample.jiffies); - - delta2 = delta - READ_ONCE(state->last_delta); - WRITE_ONCE(state->last_delta, delta); - - delta3 = delta2 - READ_ONCE(state->last_delta2); - WRITE_ONCE(state->last_delta2, delta2); - - if (delta < 0) - delta = -delta; - if (delta2 < 0) - delta2 = -delta2; - if (delta3 < 0) - delta3 = -delta3; - if (delta > delta2) - delta = delta2; - if (delta > delta3) - delta = delta3; - - /* - * delta is now minimum absolute delta. - * Round down by 1 bit on general principles, - * and limit entropy estimate to 12 bits. - */ - credit_entropy_bits(r, min_t(int, fls(delta>>1), 11)); -} - -void add_input_randomness(unsigned int type, unsigned int code, - unsigned int value) -{ - static unsigned char last_value; - - /* ignore autorepeat and the like */ - if (value == last_value) - return; + unsigned long rdseed[32 / sizeof(long)]; + size_t counter; + } block; + size_t i; + + for (i = 0; i < ARRAY_SIZE(block.rdseed); ++i) { + if (!arch_get_random_seed_long(&block.rdseed[i]) && + !arch_get_random_long(&block.rdseed[i])) + block.rdseed[i] = random_get_entropy(); + } - last_value = value; - add_timer_randomness(&input_timer_state, - (type << 4) ^ code ^ (code >> 4) ^ value); - trace_add_input_randomness(ENTROPY_BITS(&input_pool)); -} -EXPORT_SYMBOL_GPL(add_input_randomness); + spin_lock_irqsave(&input_pool.lock, flags); -static DEFINE_PER_CPU(struct fast_pool, irq_randomness); + /* seed = HASHPRF(last_key, entropy_input) */ + blake2s_final(&input_pool.hash, seed); -#ifdef ADD_INTERRUPT_BENCH -static unsigned long avg_cycles, avg_deviation; + /* next_key = HASHPRF(seed, RDSEED || 0) */ + block.counter = 0; + blake2s(next_key, (u8 *)&block, seed, sizeof(next_key), sizeof(block), sizeof(seed)); + blake2s_init_key(&input_pool.hash, BLAKE2S_HASH_SIZE, next_key, sizeof(next_key)); -#define AVG_SHIFT 8 /* Exponential average factor k=1/256 */ -#define FIXED_1_2 (1 << (AVG_SHIFT-1)) + spin_unlock_irqrestore(&input_pool.lock, flags); + memzero_explicit(next_key, sizeof(next_key)); + + while (len) { + i = min_t(size_t, len, BLAKE2S_HASH_SIZE); + /* output = HASHPRF(seed, RDSEED || ++counter) */ + ++block.counter; + blake2s(buf, (u8 *)&block, seed, i, sizeof(block), sizeof(seed)); + len -= i; + buf += i; + } -static void add_interrupt_bench(cycles_t start) -{ - long delta = random_get_entropy() - start; - - /* Use a weighted moving average */ - delta = delta - ((avg_cycles + FIXED_1_2) >> AVG_SHIFT); - avg_cycles += delta; - /* And average deviation */ - delta = abs(delta) - ((avg_deviation + FIXED_1_2) >> AVG_SHIFT); - avg_deviation += delta; + memzero_explicit(seed, sizeof(seed)); + memzero_explicit(&block, sizeof(block)); } -#else -#define add_interrupt_bench(x) -#endif - -static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs) -{ - __u32 *ptr = (__u32 *) regs; - unsigned int idx; - if (regs == NULL) - return 0; - idx = READ_ONCE(f->reg_idx); - if (idx >= sizeof(struct pt_regs) / sizeof(__u32)) - idx = 0; - ptr += idx++; - WRITE_ONCE(f->reg_idx, idx); - return *ptr; -} +#define credit_init_bits(bits) if (!crng_ready()) _credit_init_bits(bits) -void add_interrupt_randomness(int irq, int irq_flags) +static void __cold _credit_init_bits(size_t bits) { - struct entropy_store *r; - struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness); - struct pt_regs *regs = get_irq_regs(); - unsigned long now = jiffies; - cycles_t cycles = random_get_entropy(); - __u32 c_high, j_high; - __u64 ip; - unsigned long seed; - int credit = 0; - - if (cycles == 0) - cycles = get_reg(fast_pool, regs); - c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0; - j_high = (sizeof(now) > 4) ? now >> 32 : 0; - fast_pool->pool[0] ^= cycles ^ j_high ^ irq; - fast_pool->pool[1] ^= now ^ c_high; - ip = regs ? instruction_pointer(regs) : _RET_IP_; - fast_pool->pool[2] ^= ip; - fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 : - get_reg(fast_pool, regs); - - fast_mix(fast_pool); - add_interrupt_bench(cycles); - - if (unlikely(crng_init == 0)) { - if ((fast_pool->count >= 64) && - crng_fast_load((char *) fast_pool->pool, - sizeof(fast_pool->pool)) > 0) { - fast_pool->count = 0; - fast_pool->last = now; - } - return; - } - - if ((fast_pool->count < 64) && - !time_after(now, fast_pool->last + HZ)) - return; + static struct execute_work set_ready; + unsigned int new, orig, add; + unsigned long flags; - r = &input_pool; - if (!spin_trylock(&r->lock)) + if (!bits) return; - fast_pool->last = now; - __mix_pool_bytes(r, &fast_pool->pool, sizeof(fast_pool->pool)); + add = min_t(size_t, bits, POOL_BITS); - /* - * If we have architectural seed generator, produce a seed and - * add it to the pool. For the sake of paranoia don't let the - * architectural seed generator dominate the input from the - * interrupt noise. - */ - if (arch_get_random_seed_long(&seed)) { - __mix_pool_bytes(r, &seed, sizeof(seed)); - credit = 1; + do { + orig = READ_ONCE(input_pool.init_bits); + new = min_t(unsigned int, POOL_BITS, orig + add); + } while (cmpxchg(&input_pool.init_bits, orig, new) != orig); + + if (orig < POOL_READY_BITS && new >= POOL_READY_BITS) { + crng_reseed(); /* Sets crng_init to CRNG_READY under base_crng.lock. */ + execute_in_process_context(crng_set_ready, &set_ready); + process_random_ready_list(); + wake_up_interruptible(&crng_init_wait); + kill_fasync(&fasync, SIGIO, POLL_IN); + pr_notice("crng init done\n"); + if (urandom_warning.missed) + pr_notice("%d urandom warning(s) missed due to ratelimiting\n", + urandom_warning.missed); + } else if (orig < POOL_EARLY_BITS && new >= POOL_EARLY_BITS) { + spin_lock_irqsave(&base_crng.lock, flags); + /* Check if crng_init is CRNG_EMPTY, to avoid race with crng_reseed(). */ + if (crng_init == CRNG_EMPTY) { + extract_entropy(base_crng.key, sizeof(base_crng.key)); + crng_init = CRNG_EARLY; + } + spin_unlock_irqrestore(&base_crng.lock, flags); } - spin_unlock(&r->lock); - - fast_pool->count = 0; - - /* award one bit for the contents of the fast pool */ - credit_entropy_bits(r, credit + 1); } -EXPORT_SYMBOL_GPL(add_interrupt_randomness); -#ifdef CONFIG_BLOCK -void add_disk_randomness(struct gendisk *disk) -{ - if (!disk || !disk->random) - return; - /* first major is 1, so we get >= 0x200 here */ - add_timer_randomness(disk->random, 0x100 + disk_devt(disk)); - trace_add_disk_randomness(disk_devt(disk), ENTROPY_BITS(&input_pool)); -} -EXPORT_SYMBOL_GPL(add_disk_randomness); -#endif -/********************************************************************* +/********************************************************************** * - * Entropy extraction routines + * Entropy collection routines. * - *********************************************************************/ + * The following exported functions are used for pushing entropy into + * the above entropy accumulation routines: + * + * void add_device_randomness(const void *buf, size_t len); + * void add_hwgenerator_randomness(const void *buf, size_t len, size_t entropy); + * void add_bootloader_randomness(const void *buf, size_t len); + * void add_interrupt_randomness(int irq); + * void add_input_randomness(unsigned int type, unsigned int code, unsigned int value); + * void add_disk_randomness(struct gendisk *disk); + * + * add_device_randomness() adds data to the input pool that + * is likely to differ between two devices (or possibly even per boot). + * This would be things like MAC addresses or serial numbers, or the + * read-out of the RTC. This does *not* credit any actual entropy to + * the pool, but it initializes the pool to different values for devices + * that might otherwise be identical and have very little entropy + * available to them (particularly common in the embedded world). + * + * add_hwgenerator_randomness() is for true hardware RNGs, and will credit + * entropy as specified by the caller. If the entropy pool is full it will + * block until more entropy is needed. + * + * add_bootloader_randomness() is called by bootloader drivers, such as EFI + * and device tree, and credits its input depending on whether or not the + * configuration option CONFIG_RANDOM_TRUST_BOOTLOADER is set. + * + * add_interrupt_randomness() uses the interrupt timing as random + * inputs to the entropy pool. Using the cycle counters and the irq source + * as inputs, it feeds the input pool roughly once a second or after 64 + * interrupts, crediting 1 bit of entropy for whichever comes first. + * + * add_input_randomness() uses the input layer interrupt timing, as well + * as the event type information from the hardware. + * + * add_disk_randomness() uses what amounts to the seek time of block + * layer request events, on a per-disk_devt basis, as input to the + * entropy pool. Note that high-speed solid state drives with very low + * seek times do not make for good sources of entropy, as their seek + * times are usually fairly consistent. + * + * The last two routines try to estimate how many bits of entropy + * to credit. They do this by keeping track of the first and second + * order deltas of the event timings. + * + **********************************************************************/ -/* - * This function decides how many bytes to actually take from the - * given pool, and also debits the entropy count accordingly. - */ -static size_t account(struct entropy_store *r, size_t nbytes, int min, - int reserved) +static bool trust_cpu __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_CPU); +static bool trust_bootloader __ro_after_init = IS_ENABLED(CONFIG_RANDOM_TRUST_BOOTLOADER); +static int __init parse_trust_cpu(char *arg) { - int entropy_count, orig, have_bytes; - size_t ibytes, nfrac; - - BUG_ON(r->entropy_count > r->poolinfo->poolfracbits); - - /* Can we pull enough? */ -retry: - entropy_count = orig = READ_ONCE(r->entropy_count); - ibytes = nbytes; - /* never pull more than available */ - have_bytes = entropy_count >> (ENTROPY_SHIFT + 3); - - if ((have_bytes -= reserved) < 0) - have_bytes = 0; - ibytes = min_t(size_t, ibytes, have_bytes); - if (ibytes < min) - ibytes = 0; - - if (WARN_ON(entropy_count < 0)) { - pr_warn("negative entropy count: pool %s count %d\n", - r->name, entropy_count); - entropy_count = 0; - } - nfrac = ibytes << (ENTROPY_SHIFT + 3); - if ((size_t) entropy_count > nfrac) - entropy_count -= nfrac; - else - entropy_count = 0; - - if (cmpxchg(&r->entropy_count, orig, entropy_count) != orig) - goto retry; - - trace_debit_entropy(r->name, 8 * ibytes); - if (ibytes && ENTROPY_BITS(r) < random_write_wakeup_bits) { - wake_up_interruptible(&random_write_wait); - kill_fasync(&fasync, SIGIO, POLL_OUT); - } - - return ibytes; + return kstrtobool(arg, &trust_cpu); } - -/* - * This function does the actual extraction for extract_entropy and - * extract_entropy_user. - * - * Note: we assume that .poolwords is a multiple of 16 words. - */ -static void extract_buf(struct entropy_store *r, __u8 *out) +static int __init parse_trust_bootloader(char *arg) { - int i; - union { - __u32 w[5]; - unsigned long l[LONGS(20)]; - } hash; - __u32 workspace[SHA1_WORKSPACE_WORDS]; - unsigned long flags; - - /* - * If we have an architectural hardware random number - * generator, use it for SHA's initial vector - */ - sha1_init(hash.w); - for (i = 0; i < LONGS(20); i++) { - unsigned long v; - if (!arch_get_random_long(&v)) - break; - hash.l[i] = v; - } - - /* Generate a hash across the pool, 16 words (512 bits) at a time */ - spin_lock_irqsave(&r->lock, flags); - for (i = 0; i < r->poolinfo->poolwords; i += 16) - sha1_transform(hash.w, (__u8 *)(r->pool + i), workspace); - - /* - * We mix the hash back into the pool to prevent backtracking - * attacks (where the attacker knows the state of the pool - * plus the current outputs, and attempts to find previous - * ouputs), unless the hash function can be inverted. By - * mixing at least a SHA1 worth of hash data back, we make - * brute-forcing the feedback as hard as brute-forcing the - * hash. - */ - __mix_pool_bytes(r, hash.w, sizeof(hash.w)); - spin_unlock_irqrestore(&r->lock, flags); - - memzero_explicit(workspace, sizeof(workspace)); - - /* - * In case the hash function has some recognizable output - * pattern, we fold it in half. Thus, we always feed back - * twice as much data as we output. - */ - hash.w[0] ^= hash.w[3]; - hash.w[1] ^= hash.w[4]; - hash.w[2] ^= rol32(hash.w[2], 16); - - memcpy(out, &hash, EXTRACT_SIZE); - memzero_explicit(&hash, sizeof(hash)); + return kstrtobool(arg, &trust_bootloader); } +early_param("random.trust_cpu", parse_trust_cpu); +early_param("random.trust_bootloader", parse_trust_bootloader); -static ssize_t _extract_entropy(struct entropy_store *r, void *buf, - size_t nbytes, int fips) +/* + * The first collection of entropy occurs at system boot while interrupts + * are still turned off. Here we push in latent entropy, RDSEED, a timestamp, + * utsname(), and the command line. Depending on the above configuration knob, + * RDSEED may be considered sufficient for initialization. Note that much + * earlier setup may already have pushed entropy into the input pool by the + * time we get here. + */ +int __init random_init(const char *command_line) { - ssize_t ret = 0, i; - __u8 tmp[EXTRACT_SIZE]; - unsigned long flags; + ktime_t now = ktime_get_real(); + unsigned int i, arch_bytes; + unsigned long entropy; - while (nbytes) { - extract_buf(r, tmp); +#if defined(LATENT_ENTROPY_PLUGIN) + static const u8 compiletime_seed[BLAKE2S_BLOCK_SIZE] __initconst __latent_entropy; + _mix_pool_bytes(compiletime_seed, sizeof(compiletime_seed)); +#endif - if (fips) { - spin_lock_irqsave(&r->lock, flags); - if (!memcmp(tmp, r->last_data, EXTRACT_SIZE)) - panic("Hardware RNG duplicated output!\n"); - memcpy(r->last_data, tmp, EXTRACT_SIZE); - spin_unlock_irqrestore(&r->lock, flags); + for (i = 0, arch_bytes = BLAKE2S_BLOCK_SIZE; + i < BLAKE2S_BLOCK_SIZE; i += sizeof(entropy)) { + if (!arch_get_random_seed_long_early(&entropy) && + !arch_get_random_long_early(&entropy)) { + entropy = random_get_entropy(); + arch_bytes -= sizeof(entropy); } - i = min_t(int, nbytes, EXTRACT_SIZE); - memcpy(buf, tmp, i); - nbytes -= i; - buf += i; - ret += i; + _mix_pool_bytes(&entropy, sizeof(entropy)); } + _mix_pool_bytes(&now, sizeof(now)); + _mix_pool_bytes(utsname(), sizeof(*(utsname()))); + _mix_pool_bytes(command_line, strlen(command_line)); + add_latent_entropy(); - /* Wipe data just returned from memory */ - memzero_explicit(tmp, sizeof(tmp)); + if (crng_ready()) + crng_reseed(); + else if (trust_cpu) + credit_init_bits(arch_bytes * 8); - return ret; + return 0; } /* - * This function extracts randomness from the "entropy pool", and - * returns it in a buffer. + * Add device- or boot-specific data to the input pool to help + * initialize it. * - * The min parameter specifies the minimum amount we can pull before - * failing to avoid races that defeat catastrophic reseeding while the - * reserved parameter indicates how much entropy we must leave in the - * pool after each pull to avoid starving other readers. + * None of this adds any entropy; it is meant to avoid the problem of + * the entropy pool having similar initial state across largely + * identical devices. */ -static ssize_t extract_entropy(struct entropy_store *r, void *buf, - size_t nbytes, int min, int reserved) +void add_device_randomness(const void *buf, size_t len) { - __u8 tmp[EXTRACT_SIZE]; + unsigned long entropy = random_get_entropy(); unsigned long flags; - /* if last_data isn't primed, we need EXTRACT_SIZE extra bytes */ - if (fips_enabled) { - spin_lock_irqsave(&r->lock, flags); - if (!r->last_data_init) { - r->last_data_init = 1; - spin_unlock_irqrestore(&r->lock, flags); - trace_extract_entropy(r->name, EXTRACT_SIZE, - ENTROPY_BITS(r), _RET_IP_); - extract_buf(r, tmp); - spin_lock_irqsave(&r->lock, flags); - memcpy(r->last_data, tmp, EXTRACT_SIZE); - } - spin_unlock_irqrestore(&r->lock, flags); - } - - trace_extract_entropy(r->name, nbytes, ENTROPY_BITS(r), _RET_IP_); - nbytes = account(r, nbytes, min, reserved); - - return _extract_entropy(r, buf, nbytes, fips_enabled); + spin_lock_irqsave(&input_pool.lock, flags); + _mix_pool_bytes(&entropy, sizeof(entropy)); + _mix_pool_bytes(buf, len); + spin_unlock_irqrestore(&input_pool.lock, flags); } +EXPORT_SYMBOL(add_device_randomness); -#define warn_unseeded_randomness(previous) \ - _warn_unseeded_randomness(__func__, (void *) _RET_IP_, (previous)) - -static void _warn_unseeded_randomness(const char *func_name, void *caller, - void **previous) +/* + * Interface for in-kernel drivers of true hardware RNGs. + * Those devices may produce endless random bits and will be throttled + * when our pool is full. + */ +void add_hwgenerator_randomness(const void *buf, size_t len, size_t entropy) { -#ifdef CONFIG_WARN_ALL_UNSEEDED_RANDOM - const bool print_once = false; -#else - static bool print_once __read_mostly; -#endif + mix_pool_bytes(buf, len); + credit_init_bits(entropy); - if (print_once || - crng_ready() || - (previous && (caller == READ_ONCE(*previous)))) - return; - WRITE_ONCE(*previous, caller); -#ifndef CONFIG_WARN_ALL_UNSEEDED_RANDOM - print_once = true; -#endif - if (__ratelimit(&unseeded_warning)) - printk_deferred(KERN_NOTICE "random: %s called from %pS " - "with crng_init=%d\n", func_name, caller, - crng_init); + /* + * Throttle writing to once every CRNG_RESEED_INTERVAL, unless + * we're not yet initialized. + */ + if (!kthread_should_stop() && crng_ready()) + schedule_timeout_interruptible(CRNG_RESEED_INTERVAL); } +EXPORT_SYMBOL_GPL(add_hwgenerator_randomness); /* - * This function is the exported kernel interface. It returns some - * number of good random numbers, suitable for key generation, seeding - * TCP sequence numbers, etc. It does not rely on the hardware random - * number generator. For random bytes direct from the hardware RNG - * (when available), use get_random_bytes_arch(). In order to ensure - * that the randomness provided by this function is okay, the function - * wait_for_random_bytes() should be called and return 0 at least once - * at any point prior. + * Handle random seed passed by bootloader, and credit it if + * CONFIG_RANDOM_TRUST_BOOTLOADER is set. */ -static void _get_random_bytes(void *buf, int nbytes) +void __cold add_bootloader_randomness(const void *buf, size_t len) { - __u8 tmp[CHACHA_BLOCK_SIZE] __aligned(4); - - trace_get_random_bytes(nbytes, _RET_IP_); - - while (nbytes >= CHACHA_BLOCK_SIZE) { - extract_crng(buf); - buf += CHACHA_BLOCK_SIZE; - nbytes -= CHACHA_BLOCK_SIZE; - } - - if (nbytes > 0) { - extract_crng(tmp); - memcpy(buf, tmp, nbytes); - crng_backtrack_protect(tmp, nbytes); - } else - crng_backtrack_protect(tmp, CHACHA_BLOCK_SIZE); - memzero_explicit(tmp, sizeof(tmp)); + mix_pool_bytes(buf, len); + if (trust_bootloader) + credit_init_bits(len * 8); } +EXPORT_SYMBOL_GPL(add_bootloader_randomness); -void get_random_bytes(void *buf, int nbytes) -{ - static void *previous; - - warn_unseeded_randomness(&previous); - _get_random_bytes(buf, nbytes); -} -EXPORT_SYMBOL(get_random_bytes); +struct fast_pool { + struct work_struct mix; + unsigned long pool[4]; + unsigned long last; + unsigned int count; +}; +static DEFINE_PER_CPU(struct fast_pool, irq_randomness) = { +#ifdef CONFIG_64BIT +#define FASTMIX_PERM SIPHASH_PERMUTATION + .pool = { SIPHASH_CONST_0, SIPHASH_CONST_1, SIPHASH_CONST_2, SIPHASH_CONST_3 } +#else +#define FASTMIX_PERM HSIPHASH_PERMUTATION + .pool = { HSIPHASH_CONST_0, HSIPHASH_CONST_1, HSIPHASH_CONST_2, HSIPHASH_CONST_3 } +#endif +}; /* - * Each time the timer fires, we expect that we got an unpredictable - * jump in the cycle counter. Even if the timer is running on another - * CPU, the timer activity will be touching the stack of the CPU that is - * generating entropy.. - * - * Note that we don't re-arm the timer in the timer itself - we are - * happy to be scheduled away, since that just makes the load more - * complex, but we do not want the timer to keep ticking unless the - * entropy loop is running. - * - * So the re-arming always happens in the entropy loop itself. + * This is [Half]SipHash-1-x, starting from an empty key. Because + * the key is fixed, it assumes that its inputs are non-malicious, + * and therefore this has no security on its own. s represents the + * four-word SipHash state, while v represents a two-word input. */ -static void entropy_timer(struct timer_list *t) +static void fast_mix(unsigned long s[4], unsigned long v1, unsigned long v2) { - credit_entropy_bits(&input_pool, 1); + s[3] ^= v1; + FASTMIX_PERM(s[0], s[1], s[2], s[3]); + s[0] ^= v1; + s[3] ^= v2; + FASTMIX_PERM(s[0], s[1], s[2], s[3]); + s[0] ^= v2; } +#ifdef CONFIG_SMP /* - * If we have an actual cycle counter, see if we can - * generate enough entropy with timing noise + * This function is called when the CPU has just come online, with + * entry CPUHP_AP_RANDOM_ONLINE, just after CPUHP_AP_WORKQUEUE_ONLINE. */ -static void try_to_generate_entropy(void) +int __cold random_online_cpu(unsigned int cpu) { - struct { - unsigned long now; - struct timer_list timer; - } stack; + /* + * During CPU shutdown and before CPU onlining, add_interrupt_ + * randomness() may schedule mix_interrupt_randomness(), and + * set the MIX_INFLIGHT flag. However, because the worker can + * be scheduled on a different CPU during this period, that + * flag will never be cleared. For that reason, we zero out + * the flag here, which runs just after workqueues are onlined + * for the CPU again. This also has the effect of setting the + * irq randomness count to zero so that new accumulated irqs + * are fresh. + */ + per_cpu_ptr(&irq_randomness, cpu)->count = 0; + return 0; +} +#endif - stack.now = random_get_entropy(); +static void mix_interrupt_randomness(struct work_struct *work) +{ + struct fast_pool *fast_pool = container_of(work, struct fast_pool, mix); + /* + * The size of the copied stack pool is explicitly 2 longs so that we + * only ever ingest half of the siphash output each time, retaining + * the other half as the next "key" that carries over. The entropy is + * supposed to be sufficiently dispersed between bits so on average + * we don't wind up "losing" some. + */ + unsigned long pool[2]; + unsigned int count; - /* Slow counter - or none. Don't even bother */ - if (stack.now == random_get_entropy()) + /* Check to see if we're running on the wrong CPU due to hotplug. */ + local_irq_disable(); + if (fast_pool != this_cpu_ptr(&irq_randomness)) { + local_irq_enable(); return; - - timer_setup_on_stack(&stack.timer, entropy_timer, 0); - while (!crng_ready()) { - if (!timer_pending(&stack.timer)) - mod_timer(&stack.timer, jiffies+1); - mix_pool_bytes(&input_pool, &stack.now, sizeof(stack.now)); - schedule(); - stack.now = random_get_entropy(); } - del_timer_sync(&stack.timer); - destroy_timer_on_stack(&stack.timer); - mix_pool_bytes(&input_pool, &stack.now, sizeof(stack.now)); -} - -/* - * Wait for the urandom pool to be seeded and thus guaranteed to supply - * cryptographically secure random numbers. This applies to: the /dev/urandom - * device, the get_random_bytes function, and the get_random_{u32,u64,int,long} - * family of functions. Using any of these functions without first calling - * this function forfeits the guarantee of security. - * - * Returns: 0 if the urandom pool has been seeded. - * -ERESTARTSYS if the function was interrupted by a signal. - */ -int wait_for_random_bytes(void) -{ - if (likely(crng_ready())) - return 0; - - do { - int ret; - ret = wait_event_interruptible_timeout(crng_init_wait, crng_ready(), HZ); - if (ret) - return ret > 0 ? 0 : ret; + /* + * Copy the pool to the stack so that the mixer always has a + * consistent view, before we reenable irqs again. + */ + memcpy(pool, fast_pool->pool, sizeof(pool)); + count = fast_pool->count; + fast_pool->count = 0; + fast_pool->last = jiffies; + local_irq_enable(); - try_to_generate_entropy(); - } while (!crng_ready()); + mix_pool_bytes(pool, sizeof(pool)); + credit_init_bits(max(1u, (count & U16_MAX) / 64)); - return 0; + memzero_explicit(pool, sizeof(pool)); } -EXPORT_SYMBOL(wait_for_random_bytes); -/* - * Returns whether or not the urandom pool has been seeded and thus guaranteed - * to supply cryptographically secure random numbers. This applies to: the - * /dev/urandom device, the get_random_bytes function, and the get_random_{u32, - * ,u64,int,long} family of functions. - * - * Returns: true if the urandom pool has been seeded. - * false if the urandom pool has not been seeded. - */ -bool rng_is_initialized(void) -{ - return crng_ready(); -} -EXPORT_SYMBOL(rng_is_initialized); - -/* - * Add a callback function that will be invoked when the nonblocking - * pool is initialised. - * - * returns: 0 if callback is successfully added - * -EALREADY if pool is already initialised (callback not called) - * -ENOENT if module for callback is not alive - */ -int add_random_ready_callback(struct random_ready_callback *rdy) +void add_interrupt_randomness(int irq) { - struct module *owner; - unsigned long flags; - int err = -EALREADY; + enum { MIX_INFLIGHT = 1U << 31 }; + unsigned long entropy = random_get_entropy(); + struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness); + struct pt_regs *regs = get_irq_regs(); + unsigned int new_count; - if (crng_ready()) - return err; + fast_mix(fast_pool->pool, entropy, + (regs ? instruction_pointer(regs) : _RET_IP_) ^ swab(irq)); + new_count = ++fast_pool->count; - owner = rdy->owner; - if (!try_module_get(owner)) - return -ENOENT; - - spin_lock_irqsave(&random_ready_list_lock, flags); - if (crng_ready()) - goto out; - - owner = NULL; - - list_add(&rdy->list, &random_ready_list); - err = 0; - -out: - spin_unlock_irqrestore(&random_ready_list_lock, flags); + if (new_count & MIX_INFLIGHT) + return; - module_put(owner); + if (new_count < 64 && !time_is_before_jiffies(fast_pool->last + HZ)) + return; - return err; + if (unlikely(!fast_pool->mix.func)) + INIT_WORK(&fast_pool->mix, mix_interrupt_randomness); + fast_pool->count |= MIX_INFLIGHT; + queue_work_on(raw_smp_processor_id(), system_highpri_wq, &fast_pool->mix); } -EXPORT_SYMBOL(add_random_ready_callback); +EXPORT_SYMBOL_GPL(add_interrupt_randomness); + +/* There is one of these per entropy source */ +struct timer_rand_state { + unsigned long last_time; + long last_delta, last_delta2; +}; /* - * Delete a previously registered readiness callback function. + * This function adds entropy to the entropy "pool" by using timing + * delays. It uses the timer_rand_state structure to make an estimate + * of how many bits of entropy this call has added to the pool. The + * value "num" is also added to the pool; it should somehow describe + * the type of event that just happened. */ -void del_random_ready_callback(struct random_ready_callback *rdy) +static void add_timer_randomness(struct timer_rand_state *state, unsigned int num) { - unsigned long flags; - struct module *owner = NULL; + unsigned long entropy = random_get_entropy(), now = jiffies, flags; + long delta, delta2, delta3; + unsigned int bits; - spin_lock_irqsave(&random_ready_list_lock, flags); - if (!list_empty(&rdy->list)) { - list_del_init(&rdy->list); - owner = rdy->owner; + /* + * If we're in a hard IRQ, add_interrupt_randomness() will be called + * sometime after, so mix into the fast pool. + */ + if (in_irq()) { + fast_mix(this_cpu_ptr(&irq_randomness)->pool, entropy, num); + } else { + spin_lock_irqsave(&input_pool.lock, flags); + _mix_pool_bytes(&entropy, sizeof(entropy)); + _mix_pool_bytes(&num, sizeof(num)); + spin_unlock_irqrestore(&input_pool.lock, flags); } - spin_unlock_irqrestore(&random_ready_list_lock, flags); - module_put(owner); -} -EXPORT_SYMBOL(del_random_ready_callback); + if (crng_ready()) + return; -/* - * This function will use the architecture-specific hardware random - * number generator if it is available. The arch-specific hw RNG will - * almost certainly be faster than what we can do in software, but it - * is impossible to verify that it is implemented securely (as - * opposed, to, say, the AES encryption of a sequence number using a - * key known by the NSA). So it's useful if we need the speed, but - * only if we're willing to trust the hardware manufacturer not to - * have put in a back door. - * - * Return number of bytes filled in. - */ -int __must_check get_random_bytes_arch(void *buf, int nbytes) -{ - int left = nbytes; - char *p = buf; + /* + * Calculate number of bits of randomness we probably added. + * We take into account the first, second and third-order deltas + * in order to make our estimate. + */ + delta = now - READ_ONCE(state->last_time); + WRITE_ONCE(state->last_time, now); - trace_get_random_bytes_arch(left, _RET_IP_); - while (left) { - unsigned long v; - int chunk = min_t(int, left, sizeof(unsigned long)); + delta2 = delta - READ_ONCE(state->last_delta); + WRITE_ONCE(state->last_delta, delta); - if (!arch_get_random_long(&v)) - break; + delta3 = delta2 - READ_ONCE(state->last_delta2); + WRITE_ONCE(state->last_delta2, delta2); - memcpy(p, &v, chunk); - p += chunk; - left -= chunk; - } + if (delta < 0) + delta = -delta; + if (delta2 < 0) + delta2 = -delta2; + if (delta3 < 0) + delta3 = -delta3; + if (delta > delta2) + delta = delta2; + if (delta > delta3) + delta = delta3; + + /* + * delta is now minimum absolute delta. Round down by 1 bit + * on general principles, and limit entropy estimate to 11 bits. + */ + bits = min(fls(delta >> 1), 11); - return nbytes - left; + /* + * As mentioned above, if we're in a hard IRQ, add_interrupt_randomness() + * will run after this, which uses a different crediting scheme of 1 bit + * per every 64 interrupts. In order to let that function do accounting + * close to the one in this function, we credit a full 64/64 bit per bit, + * and then subtract one to account for the extra one added. + */ + if (in_irq()) + this_cpu_ptr(&irq_randomness)->count += max(1u, bits * 64) - 1; + else + _credit_init_bits(bits); } -EXPORT_SYMBOL(get_random_bytes_arch); -/* - * init_std_data - initialize pool with system data - * - * @r: pool to initialize - * - * This function clears the pool's entropy count and mixes some system - * data into the pool to prepare it for use. The pool is not cleared - * as that can only decrease the entropy in the pool. - */ -static void __init init_std_data(struct entropy_store *r) +void add_input_randomness(unsigned int type, unsigned int code, unsigned int value) { - int i; - ktime_t now = ktime_get_real(); - unsigned long rv; - - mix_pool_bytes(r, &now, sizeof(now)); - for (i = r->poolinfo->poolbytes; i > 0; i -= sizeof(rv)) { - if (!arch_get_random_seed_long(&rv) && - !arch_get_random_long(&rv)) - rv = random_get_entropy(); - mix_pool_bytes(r, &rv, sizeof(rv)); - } - mix_pool_bytes(r, utsname(), sizeof(*(utsname()))); + static unsigned char last_value; + static struct timer_rand_state input_timer_state = { INITIAL_JIFFIES }; + + /* Ignore autorepeat and the like. */ + if (value == last_value) + return; + + last_value = value; + add_timer_randomness(&input_timer_state, + (type << 4) ^ code ^ (code >> 4) ^ value); } +EXPORT_SYMBOL_GPL(add_input_randomness); -/* - * Note that setup_arch() may call add_device_randomness() - * long before we get here. This allows seeding of the pools - * with some platform dependent data very early in the boot - * process. But it limits our options here. We must use - * statically allocated structures that already have all - * initializations complete at compile time. We should also - * take care not to overwrite the precious per platform data - * we were given. - */ -int __init rand_initialize(void) +#ifdef CONFIG_BLOCK +void add_disk_randomness(struct gendisk *disk) { - init_std_data(&input_pool); - if (crng_need_final_init) - crng_finalize_init(&primary_crng); - crng_initialize_primary(&primary_crng); - crng_global_init_time = jiffies; - if (ratelimit_disable) { - urandom_warning.interval = 0; - unseeded_warning.interval = 0; - } - return 0; + if (!disk || !disk->random) + return; + /* First major is 1, so we get >= 0x200 here. */ + add_timer_randomness(disk->random, 0x100 + disk_devt(disk)); } +EXPORT_SYMBOL_GPL(add_disk_randomness); -#ifdef CONFIG_BLOCK -void rand_initialize_disk(struct gendisk *disk) +void __cold rand_initialize_disk(struct gendisk *disk) { struct timer_rand_state *state; @@ -1847,116 +1141,189 @@ void rand_initialize_disk(struct gendisk *disk) } #endif -static ssize_t -urandom_read_nowarn(struct file *file, char __user *buf, size_t nbytes, - loff_t *ppos) +/* + * Each time the timer fires, we expect that we got an unpredictable + * jump in the cycle counter. Even if the timer is running on another + * CPU, the timer activity will be touching the stack of the CPU that is + * generating entropy.. + * + * Note that we don't re-arm the timer in the timer itself - we are + * happy to be scheduled away, since that just makes the load more + * complex, but we do not want the timer to keep ticking unless the + * entropy loop is running. + * + * So the re-arming always happens in the entropy loop itself. + */ +static void __cold entropy_timer(struct timer_list *t) { - int ret; - - nbytes = min_t(size_t, nbytes, INT_MAX >> (ENTROPY_SHIFT + 3)); - ret = extract_crng_user(buf, nbytes); - trace_urandom_read(8 * nbytes, 0, ENTROPY_BITS(&input_pool)); - return ret; + credit_init_bits(1); } -static ssize_t -urandom_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) +/* + * If we have an actual cycle counter, see if we can + * generate enough entropy with timing noise + */ +static void __cold try_to_generate_entropy(void) { - unsigned long flags; - static int maxwarn = 10; + struct { + unsigned long entropy; + struct timer_list timer; + } stack; + + stack.entropy = random_get_entropy(); - if (!crng_ready() && maxwarn > 0) { - maxwarn--; - if (__ratelimit(&urandom_warning)) - pr_notice("%s: uninitialized urandom read (%zd bytes read)\n", - current->comm, nbytes); - spin_lock_irqsave(&primary_crng.lock, flags); - crng_init_cnt = 0; - spin_unlock_irqrestore(&primary_crng.lock, flags); + /* Slow counter - or none. Don't even bother */ + if (stack.entropy == random_get_entropy()) + return; + + timer_setup_on_stack(&stack.timer, entropy_timer, 0); + while (!crng_ready() && !signal_pending(current)) { + if (!timer_pending(&stack.timer)) + mod_timer(&stack.timer, jiffies + 1); + mix_pool_bytes(&stack.entropy, sizeof(stack.entropy)); + schedule(); + stack.entropy = random_get_entropy(); } - return urandom_read_nowarn(file, buf, nbytes, ppos); + del_timer_sync(&stack.timer); + destroy_timer_on_stack(&stack.timer); + mix_pool_bytes(&stack.entropy, sizeof(stack.entropy)); } -static ssize_t -random_read(struct file *file, char __user *buf, size_t nbytes, loff_t *ppos) + +/********************************************************************** + * + * Userspace reader/writer interfaces. + * + * getrandom(2) is the primary modern interface into the RNG and should + * be used in preference to anything else. + * + * Reading from /dev/random has the same functionality as calling + * getrandom(2) with flags=0. In earlier versions, however, it had + * vastly different semantics and should therefore be avoided, to + * prevent backwards compatibility issues. + * + * Reading from /dev/urandom has the same functionality as calling + * getrandom(2) with flags=GRND_INSECURE. Because it does not block + * waiting for the RNG to be ready, it should not be used. + * + * Writing to either /dev/random or /dev/urandom adds entropy to + * the input pool but does not credit it. + * + * Polling on /dev/random indicates when the RNG is initialized, on + * the read side, and when it wants new entropy, on the write side. + * + * Both /dev/random and /dev/urandom have the same set of ioctls for + * adding entropy, getting the entropy count, zeroing the count, and + * reseeding the crng. + * + **********************************************************************/ + +SYSCALL_DEFINE3(getrandom, char __user *, ubuf, size_t, len, unsigned int, flags) { + struct iov_iter iter; + struct iovec iov; int ret; - ret = wait_for_random_bytes(); - if (ret != 0) + if (flags & ~(GRND_NONBLOCK | GRND_RANDOM | GRND_INSECURE)) + return -EINVAL; + + /* + * Requesting insecure and blocking randomness at the same time makes + * no sense. + */ + if ((flags & (GRND_INSECURE | GRND_RANDOM)) == (GRND_INSECURE | GRND_RANDOM)) + return -EINVAL; + + if (!crng_ready() && !(flags & GRND_INSECURE)) { + if (flags & GRND_NONBLOCK) + return -EAGAIN; + ret = wait_for_random_bytes(); + if (unlikely(ret)) + return ret; + } + + ret = import_single_range(READ, ubuf, len, &iov, &iter); + if (unlikely(ret)) return ret; - return urandom_read_nowarn(file, buf, nbytes, ppos); + return get_random_bytes_user(&iter); } -static __poll_t -random_poll(struct file *file, poll_table * wait) +static __poll_t random_poll(struct file *file, poll_table *wait) { - __poll_t mask; - poll_wait(file, &crng_init_wait, wait); - poll_wait(file, &random_write_wait, wait); - mask = 0; - if (crng_ready()) - mask |= EPOLLIN | EPOLLRDNORM; - if (ENTROPY_BITS(&input_pool) < random_write_wakeup_bits) - mask |= EPOLLOUT | EPOLLWRNORM; - return mask; + return crng_ready() ? EPOLLIN | EPOLLRDNORM : EPOLLOUT | EPOLLWRNORM; } -static int -write_pool(struct entropy_store *r, const char __user *buffer, size_t count) +static ssize_t write_pool_user(struct iov_iter *iter) { - size_t bytes; - __u32 t, buf[16]; - const char __user *p = buffer; + u8 block[BLAKE2S_BLOCK_SIZE]; + ssize_t ret = 0; + size_t copied; - while (count > 0) { - int b, i = 0; + if (unlikely(!iov_iter_count(iter))) + return 0; - bytes = min(count, sizeof(buf)); - if (copy_from_user(&buf, p, bytes)) - return -EFAULT; + for (;;) { + copied = copy_from_iter(block, sizeof(block), iter); + ret += copied; + mix_pool_bytes(block, copied); + if (!iov_iter_count(iter) || copied != sizeof(block)) + break; - for (b = bytes ; b > 0 ; b -= sizeof(__u32), i++) { - if (!arch_get_random_int(&t)) + BUILD_BUG_ON(PAGE_SIZE % sizeof(block) != 0); + if (ret % PAGE_SIZE == 0) { + if (signal_pending(current)) break; - buf[i] ^= t; + cond_resched(); } + } + + memzero_explicit(block, sizeof(block)); + return ret ? ret : -EFAULT; +} + +static ssize_t random_write_iter(struct kiocb *kiocb, struct iov_iter *iter) +{ + return write_pool_user(iter); +} - count -= bytes; - p += bytes; +static ssize_t urandom_read_iter(struct kiocb *kiocb, struct iov_iter *iter) +{ + static int maxwarn = 10; - mix_pool_bytes(r, buf, bytes); - cond_resched(); + if (!crng_ready()) { + if (!ratelimit_disable && maxwarn <= 0) + ++urandom_warning.missed; + else if (ratelimit_disable || __ratelimit(&urandom_warning)) { + --maxwarn; + pr_notice("%s: uninitialized urandom read (%zu bytes read)\n", + current->comm, iov_iter_count(iter)); + } } - return 0; + return get_random_bytes_user(iter); } -static ssize_t random_write(struct file *file, const char __user *buffer, - size_t count, loff_t *ppos) +static ssize_t random_read_iter(struct kiocb *kiocb, struct iov_iter *iter) { - size_t ret; + int ret; - ret = write_pool(&input_pool, buffer, count); - if (ret) + ret = wait_for_random_bytes(); + if (ret != 0) return ret; - - return (ssize_t)count; + return get_random_bytes_user(iter); } static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg) { - int size, ent_count; int __user *p = (int __user *)arg; - int retval; + int ent_count; switch (cmd) { case RNDGETENTCNT: - /* inherently racy, no point locking */ - ent_count = ENTROPY_BITS(&input_pool); - if (put_user(ent_count, p)) + /* Inherently racy, no point locking. */ + if (put_user(input_pool.init_bits, p)) return -EFAULT; return 0; case RNDADDTOENTCNT: @@ -1964,41 +1331,48 @@ static long random_ioctl(struct file *f, unsigned int cmd, unsigned long arg) return -EPERM; if (get_user(ent_count, p)) return -EFAULT; - return credit_entropy_bits_safe(&input_pool, ent_count); - case RNDADDENTROPY: + if (ent_count < 0) + return -EINVAL; + credit_init_bits(ent_count); + return 0; + case RNDADDENTROPY: { + struct iov_iter iter; + struct iovec iov; + ssize_t ret; + int len; + if (!capable(CAP_SYS_ADMIN)) return -EPERM; if (get_user(ent_count, p++)) return -EFAULT; if (ent_count < 0) return -EINVAL; - if (get_user(size, p++)) + if (get_user(len, p++)) + return -EFAULT; + ret = import_single_range(WRITE, p, len, &iov, &iter); + if (unlikely(ret)) + return ret; + ret = write_pool_user(&iter); + if (unlikely(ret < 0)) + return ret; + /* Since we're crediting, enforce that it was all written into the pool. */ + if (unlikely(ret != len)) return -EFAULT; - retval = write_pool(&input_pool, (const char __user *)p, - size); - if (retval < 0) - return retval; - return credit_entropy_bits_safe(&input_pool, ent_count); + credit_init_bits(ent_count); + return 0; + } case RNDZAPENTCNT: case RNDCLEARPOOL: - /* - * Clear the entropy pool counters. We no longer clear - * the entropy pool, as that's silly. - */ + /* No longer has any effect. */ if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (xchg(&input_pool.entropy_count, 0) && random_write_wakeup_bits) { - wake_up_interruptible(&random_write_wait); - kill_fasync(&fasync, SIGIO, POLL_OUT); - } return 0; case RNDRESEEDCRNG: if (!capable(CAP_SYS_ADMIN)) return -EPERM; - if (crng_init < 2) + if (!crng_ready()) return -ENODATA; - crng_reseed(&primary_crng, &input_pool); - WRITE_ONCE(crng_global_init_time, jiffies - 1); + crng_reseed(); return 0; default: return -EINVAL; @@ -2011,55 +1385,56 @@ static int random_fasync(int fd, struct file *filp, int on) } const struct file_operations random_fops = { - .read = random_read, - .write = random_write, - .poll = random_poll, + .read_iter = random_read_iter, + .write_iter = random_write_iter, + .poll = random_poll, .unlocked_ioctl = random_ioctl, .compat_ioctl = compat_ptr_ioctl, .fasync = random_fasync, .llseek = noop_llseek, + .splice_read = generic_file_splice_read, + .splice_write = iter_file_splice_write, }; const struct file_operations urandom_fops = { - .read = urandom_read, - .write = random_write, + .read_iter = urandom_read_iter, + .write_iter = random_write_iter, .unlocked_ioctl = random_ioctl, .compat_ioctl = compat_ptr_ioctl, .fasync = random_fasync, .llseek = noop_llseek, + .splice_read = generic_file_splice_read, + .splice_write = iter_file_splice_write, }; -SYSCALL_DEFINE3(getrandom, char __user *, buf, size_t, count, - unsigned int, flags) -{ - int ret; - - if (flags & ~(GRND_NONBLOCK|GRND_RANDOM|GRND_INSECURE)) - return -EINVAL; - - /* - * Requesting insecure and blocking randomness at the same time makes - * no sense. - */ - if ((flags & (GRND_INSECURE|GRND_RANDOM)) == (GRND_INSECURE|GRND_RANDOM)) - return -EINVAL; - - if (count > INT_MAX) - count = INT_MAX; - - if (!(flags & GRND_INSECURE) && !crng_ready()) { - if (flags & GRND_NONBLOCK) - return -EAGAIN; - ret = wait_for_random_bytes(); - if (unlikely(ret)) - return ret; - } - return urandom_read_nowarn(NULL, buf, count, NULL); -} /******************************************************************** * - * Sysctl interface + * Sysctl interface. + * + * These are partly unused legacy knobs with dummy values to not break + * userspace and partly still useful things. They are usually accessible + * in /proc/sys/kernel/random/ and are as follows: + * + * - boot_id - a UUID representing the current boot. + * + * - uuid - a random UUID, different each time the file is read. + * + * - poolsize - the number of bits of entropy that the input pool can + * hold, tied to the POOL_BITS constant. + * + * - entropy_avail - the number of bits of entropy currently in the + * input pool. Always <= poolsize. + * + * - write_wakeup_threshold - the amount of entropy in the input pool + * below which write polls to /dev/random will unblock, requesting + * more entropy, tied to the POOL_READY_BITS constant. It is writable + * to avoid breaking old userspaces, but writing to it does not + * change any behavior of the RNG. + * + * - urandom_min_reseed_secs - fixed to the value CRNG_RESEED_INTERVAL. + * It is writable to avoid breaking old userspaces, but writing + * to it does not change any behavior of the RNG. * ********************************************************************/ @@ -2067,25 +1442,28 @@ SYSCALL_DEFINE3(getrandom, char __user *, buf, size_t, count, #include -static int min_write_thresh; -static int max_write_thresh = INPUT_POOL_WORDS * 32; -static int random_min_urandom_seed = 60; -static char sysctl_bootid[16]; +static int sysctl_random_min_urandom_seed = CRNG_RESEED_INTERVAL / HZ; +static int sysctl_random_write_wakeup_bits = POOL_READY_BITS; +static int sysctl_poolsize = POOL_BITS; +static u8 sysctl_bootid[UUID_SIZE]; /* * This function is used to return both the bootid UUID, and random - * UUID. The difference is in whether table->data is NULL; if it is, + * UUID. The difference is in whether table->data is NULL; if it is, * then a new UUID is generated and returned to the user. - * - * If the user accesses this via the proc interface, the UUID will be - * returned as an ASCII string in the standard UUID format; if via the - * sysctl system call, as 16 bytes of binary data. */ -static int proc_do_uuid(struct ctl_table *table, int write, - void *buffer, size_t *lenp, loff_t *ppos) -{ - struct ctl_table fake_table; - unsigned char buf[64], tmp_uuid[16], *uuid; +static int proc_do_uuid(struct ctl_table *table, int write, void *buf, + size_t *lenp, loff_t *ppos) +{ + u8 tmp_uuid[UUID_SIZE], *uuid; + char uuid_string[UUID_STRING_LEN + 1]; + struct ctl_table fake_table = { + .data = uuid_string, + .maxlen = UUID_STRING_LEN + }; + + if (write) + return -EPERM; uuid = table->data; if (!uuid) { @@ -2100,32 +1478,17 @@ static int proc_do_uuid(struct ctl_table *table, int write, spin_unlock(&bootid_spinlock); } - sprintf(buf, "%pU", uuid); - - fake_table.data = buf; - fake_table.maxlen = sizeof(buf); - - return proc_dostring(&fake_table, write, buffer, lenp, ppos); + snprintf(uuid_string, sizeof(uuid_string), "%pU", uuid); + return proc_dostring(&fake_table, 0, buf, lenp, ppos); } -/* - * Return entropy available scaled to integral bits - */ -static int proc_do_entropy(struct ctl_table *table, int write, - void *buffer, size_t *lenp, loff_t *ppos) +/* The same as proc_dointvec, but writes don't change anything. */ +static int proc_do_rointvec(struct ctl_table *table, int write, void *buf, + size_t *lenp, loff_t *ppos) { - struct ctl_table fake_table; - int entropy_count; - - entropy_count = *(int *)table->data >> ENTROPY_SHIFT; - - fake_table.data = &entropy_count; - fake_table.maxlen = sizeof(entropy_count); - - return proc_dointvec(&fake_table, write, buffer, lenp, ppos); + return write ? 0 : proc_dointvec(table, 0, buf, lenp, ppos); } -static int sysctl_poolsize = INPUT_POOL_WORDS * 32; extern struct ctl_table random_table[]; struct ctl_table random_table[] = { { @@ -2137,222 +1500,36 @@ struct ctl_table random_table[] = { }, { .procname = "entropy_avail", + .data = &input_pool.init_bits, .maxlen = sizeof(int), .mode = 0444, - .proc_handler = proc_do_entropy, - .data = &input_pool.entropy_count, + .proc_handler = proc_dointvec, }, { .procname = "write_wakeup_threshold", - .data = &random_write_wakeup_bits, + .data = &sysctl_random_write_wakeup_bits, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec_minmax, - .extra1 = &min_write_thresh, - .extra2 = &max_write_thresh, + .proc_handler = proc_do_rointvec, }, { .procname = "urandom_min_reseed_secs", - .data = &random_min_urandom_seed, + .data = &sysctl_random_min_urandom_seed, .maxlen = sizeof(int), .mode = 0644, - .proc_handler = proc_dointvec, + .proc_handler = proc_do_rointvec, }, { .procname = "boot_id", .data = &sysctl_bootid, - .maxlen = 16, .mode = 0444, .proc_handler = proc_do_uuid, }, { .procname = "uuid", - .maxlen = 16, .mode = 0444, .proc_handler = proc_do_uuid, }, -#ifdef ADD_INTERRUPT_BENCH - { - .procname = "add_interrupt_avg_cycles", - .data = &avg_cycles, - .maxlen = sizeof(avg_cycles), - .mode = 0444, - .proc_handler = proc_doulongvec_minmax, - }, - { - .procname = "add_interrupt_avg_deviation", - .data = &avg_deviation, - .maxlen = sizeof(avg_deviation), - .mode = 0444, - .proc_handler = proc_doulongvec_minmax, - }, -#endif { } }; -#endif /* CONFIG_SYSCTL */ - -struct batched_entropy { - union { - u64 entropy_u64[CHACHA_BLOCK_SIZE / sizeof(u64)]; - u32 entropy_u32[CHACHA_BLOCK_SIZE / sizeof(u32)]; - }; - unsigned int position; - spinlock_t batch_lock; -}; - -/* - * Get a random word for internal kernel use only. The quality of the random - * number is good as /dev/urandom, but there is no backtrack protection, with - * the goal of being quite fast and not depleting entropy. In order to ensure - * that the randomness provided by this function is okay, the function - * wait_for_random_bytes() should be called and return 0 at least once at any - * point prior. - */ -static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_u64) = { - .batch_lock = __SPIN_LOCK_UNLOCKED(batched_entropy_u64.lock), -}; - -u64 get_random_u64(void) -{ - u64 ret; - unsigned long flags; - struct batched_entropy *batch; - static void *previous; - - warn_unseeded_randomness(&previous); - - batch = raw_cpu_ptr(&batched_entropy_u64); - spin_lock_irqsave(&batch->batch_lock, flags); - if (batch->position % ARRAY_SIZE(batch->entropy_u64) == 0) { - extract_crng((u8 *)batch->entropy_u64); - batch->position = 0; - } - ret = batch->entropy_u64[batch->position++]; - spin_unlock_irqrestore(&batch->batch_lock, flags); - return ret; -} -EXPORT_SYMBOL(get_random_u64); - -static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_u32) = { - .batch_lock = __SPIN_LOCK_UNLOCKED(batched_entropy_u32.lock), -}; -u32 get_random_u32(void) -{ - u32 ret; - unsigned long flags; - struct batched_entropy *batch; - static void *previous; - - warn_unseeded_randomness(&previous); - - batch = raw_cpu_ptr(&batched_entropy_u32); - spin_lock_irqsave(&batch->batch_lock, flags); - if (batch->position % ARRAY_SIZE(batch->entropy_u32) == 0) { - extract_crng((u8 *)batch->entropy_u32); - batch->position = 0; - } - ret = batch->entropy_u32[batch->position++]; - spin_unlock_irqrestore(&batch->batch_lock, flags); - return ret; -} -EXPORT_SYMBOL(get_random_u32); - -/* It's important to invalidate all potential batched entropy that might - * be stored before the crng is initialized, which we can do lazily by - * simply resetting the counter to zero so that it's re-extracted on the - * next usage. */ -static void invalidate_batched_entropy(void) -{ - int cpu; - unsigned long flags; - - for_each_possible_cpu (cpu) { - struct batched_entropy *batched_entropy; - - batched_entropy = per_cpu_ptr(&batched_entropy_u32, cpu); - spin_lock_irqsave(&batched_entropy->batch_lock, flags); - batched_entropy->position = 0; - spin_unlock(&batched_entropy->batch_lock); - - batched_entropy = per_cpu_ptr(&batched_entropy_u64, cpu); - spin_lock(&batched_entropy->batch_lock); - batched_entropy->position = 0; - spin_unlock_irqrestore(&batched_entropy->batch_lock, flags); - } -} - -/** - * randomize_page - Generate a random, page aligned address - * @start: The smallest acceptable address the caller will take. - * @range: The size of the area, starting at @start, within which the - * random address must fall. - * - * If @start + @range would overflow, @range is capped. - * - * NOTE: Historical use of randomize_range, which this replaces, presumed that - * @start was already page aligned. We now align it regardless. - * - * Return: A page aligned address within [start, start + range). On error, - * @start is returned. - */ -unsigned long -randomize_page(unsigned long start, unsigned long range) -{ - if (!PAGE_ALIGNED(start)) { - range -= PAGE_ALIGN(start) - start; - start = PAGE_ALIGN(start); - } - - if (start > ULONG_MAX - range) - range = ULONG_MAX - start; - - range >>= PAGE_SHIFT; - - if (range == 0) - return start; - - return start + (get_random_long() % range << PAGE_SHIFT); -} - -/* Interface for in-kernel drivers of true hardware RNGs. - * Those devices may produce endless random bits and will be throttled - * when our pool is full. - */ -void add_hwgenerator_randomness(const char *buffer, size_t count, - size_t entropy) -{ - struct entropy_store *poolp = &input_pool; - - if (unlikely(crng_init == 0)) { - size_t ret = crng_fast_load(buffer, count); - count -= ret; - buffer += ret; - if (!count || crng_init == 0) - return; - } - - /* Suspend writing if we're above the trickle threshold. - * We'll be woken up again once below random_write_wakeup_thresh, - * or when the calling thread is about to terminate. - */ - wait_event_interruptible(random_write_wait, - !system_wq || kthread_should_stop() || - ENTROPY_BITS(&input_pool) <= random_write_wakeup_bits); - mix_pool_bytes(poolp, buffer, count); - credit_entropy_bits(poolp, entropy); -} -EXPORT_SYMBOL_GPL(add_hwgenerator_randomness); - -/* Handle random seed passed by bootloader. - * If the seed is trustworthy, it would be regarded as hardware RNGs. Otherwise - * it would be regarded as device data. - * The decision is controlled by CONFIG_RANDOM_TRUST_BOOTLOADER. - */ -void add_bootloader_randomness(const void *buf, unsigned int size) -{ - if (IS_ENABLED(CONFIG_RANDOM_TRUST_BOOTLOADER)) - add_hwgenerator_randomness(buf, size, size * 8); - else - add_device_randomness(buf, size); -} -EXPORT_SYMBOL_GPL(add_bootloader_randomness); +#endif /* CONFIG_SYSCTL */ diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index b9ac357e465db..5d820037e2918 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -1351,7 +1351,7 @@ static void vmbus_isr(void) tasklet_schedule(&hv_cpu->msg_dpc); } - add_interrupt_randomness(hv_get_vector(), 0); + add_interrupt_randomness(hv_get_vector()); } /* diff --git a/drivers/media/test-drivers/vim2m.c b/drivers/media/test-drivers/vim2m.c index a776bb8e0e093..a24624353f9ed 100644 --- a/drivers/media/test-drivers/vim2m.c +++ b/drivers/media/test-drivers/vim2m.c @@ -1325,12 +1325,6 @@ static int vim2m_probe(struct platform_device *pdev) vfd->lock = &dev->dev_mutex; vfd->v4l2_dev = &dev->v4l2_dev; - ret = video_register_device(vfd, VFL_TYPE_VIDEO, 0); - if (ret) { - v4l2_err(&dev->v4l2_dev, "Failed to register video device\n"); - goto error_v4l2; - } - video_set_drvdata(vfd, dev); v4l2_info(&dev->v4l2_dev, "Device registered as /dev/video%d\n", vfd->num); @@ -1353,12 +1347,20 @@ static int vim2m_probe(struct platform_device *pdev) media_device_init(&dev->mdev); dev->mdev.ops = &m2m_media_ops; dev->v4l2_dev.mdev = &dev->mdev; +#endif + + ret = video_register_device(vfd, VFL_TYPE_VIDEO, 0); + if (ret) { + v4l2_err(&dev->v4l2_dev, "Failed to register video device\n"); + goto error_m2m; + } +#ifdef CONFIG_MEDIA_CONTROLLER ret = v4l2_m2m_register_media_controller(dev->m2m_dev, vfd, MEDIA_ENT_F_PROC_VIDEO_SCALER); if (ret) { v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n"); - goto error_dev; + goto error_v4l2; } ret = media_device_register(&dev->mdev); @@ -1373,11 +1375,13 @@ static int vim2m_probe(struct platform_device *pdev) error_m2m_mc: v4l2_m2m_unregister_media_controller(dev->m2m_dev); #endif -error_dev: +error_v4l2: video_unregister_device(&dev->vfd); /* vim2m_device_release called by video_unregister_device to release various objects */ return ret; -error_v4l2: +error_m2m: + v4l2_m2m_release(dev->m2m_dev); +error_dev: v4l2_device_unregister(&dev->v4l2_dev); error_free: kfree(dev); diff --git a/drivers/net/Kconfig b/drivers/net/Kconfig index cb865b7ec3750..f208080243055 100644 --- a/drivers/net/Kconfig +++ b/drivers/net/Kconfig @@ -80,7 +80,6 @@ config WIREGUARD select CRYPTO select CRYPTO_LIB_CURVE25519 select CRYPTO_LIB_CHACHA20POLY1305 - select CRYPTO_LIB_BLAKE2S select CRYPTO_CHACHA20_X86_64 if X86 && 64BIT select CRYPTO_POLY1305_X86_64 if X86 && 64BIT select CRYPTO_BLAKE2S_X86 if X86 && 64BIT diff --git a/drivers/net/wireguard/noise.c b/drivers/net/wireguard/noise.c index c0cfd9b36c0b5..720952b92e784 100644 --- a/drivers/net/wireguard/noise.c +++ b/drivers/net/wireguard/noise.c @@ -302,6 +302,41 @@ void wg_noise_set_static_identity_private_key( static_identity->static_public, private_key); } +static void hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen, const size_t keylen) +{ + struct blake2s_state state; + u8 x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(u32)) = { 0 }; + u8 i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(u32)); + int i; + + if (keylen > BLAKE2S_BLOCK_SIZE) { + blake2s_init(&state, BLAKE2S_HASH_SIZE); + blake2s_update(&state, key, keylen); + blake2s_final(&state, x_key); + } else + memcpy(x_key, key, keylen); + + for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i) + x_key[i] ^= 0x36; + + blake2s_init(&state, BLAKE2S_HASH_SIZE); + blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE); + blake2s_update(&state, in, inlen); + blake2s_final(&state, i_hash); + + for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i) + x_key[i] ^= 0x5c ^ 0x36; + + blake2s_init(&state, BLAKE2S_HASH_SIZE); + blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE); + blake2s_update(&state, i_hash, BLAKE2S_HASH_SIZE); + blake2s_final(&state, i_hash); + + memcpy(out, i_hash, BLAKE2S_HASH_SIZE); + memzero_explicit(x_key, BLAKE2S_BLOCK_SIZE); + memzero_explicit(i_hash, BLAKE2S_HASH_SIZE); +} + /* This is Hugo Krawczyk's HKDF: * - https://eprint.iacr.org/2010/264.pdf * - https://tools.ietf.org/html/rfc5869 @@ -322,14 +357,14 @@ static void kdf(u8 *first_dst, u8 *second_dst, u8 *third_dst, const u8 *data, ((third_len || third_dst) && (!second_len || !second_dst)))); /* Extract entropy from data into secret */ - blake2s256_hmac(secret, data, chaining_key, data_len, NOISE_HASH_LEN); + hmac(secret, data, chaining_key, data_len, NOISE_HASH_LEN); if (!first_dst || !first_len) goto out; /* Expand first key: key = secret, data = 0x1 */ output[0] = 1; - blake2s256_hmac(output, output, secret, 1, BLAKE2S_HASH_SIZE); + hmac(output, output, secret, 1, BLAKE2S_HASH_SIZE); memcpy(first_dst, output, first_len); if (!second_dst || !second_len) @@ -337,8 +372,7 @@ static void kdf(u8 *first_dst, u8 *second_dst, u8 *third_dst, const u8 *data, /* Expand second key: key = secret, data = first-key || 0x2 */ output[BLAKE2S_HASH_SIZE] = 2; - blake2s256_hmac(output, output, secret, BLAKE2S_HASH_SIZE + 1, - BLAKE2S_HASH_SIZE); + hmac(output, output, secret, BLAKE2S_HASH_SIZE + 1, BLAKE2S_HASH_SIZE); memcpy(second_dst, output, second_len); if (!third_dst || !third_len) @@ -346,8 +380,7 @@ static void kdf(u8 *first_dst, u8 *second_dst, u8 *third_dst, const u8 *data, /* Expand third key: key = secret, data = second-key || 0x3 */ output[BLAKE2S_HASH_SIZE] = 3; - blake2s256_hmac(output, output, secret, BLAKE2S_HASH_SIZE + 1, - BLAKE2S_HASH_SIZE); + hmac(output, output, secret, BLAKE2S_HASH_SIZE + 1, BLAKE2S_HASH_SIZE); memcpy(third_dst, output, third_len); out: diff --git a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c index 902ac81699484..083ff72976cf0 100644 --- a/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c +++ b/drivers/staging/rtl8723bs/os_dep/ioctl_linux.c @@ -1351,9 +1351,11 @@ static int rtw_wx_set_scan(struct net_device *dev, struct iw_request_info *a, sec_len = *(pos++); len -= 1; - if (sec_len > 0 && sec_len <= len) { + if (sec_len > 0 && + sec_len <= len && + sec_len <= 32) { ssid[ssid_index].SsidLength = sec_len; - memcpy(ssid[ssid_index].Ssid, pos, ssid[ssid_index].SsidLength); + memcpy(ssid[ssid_index].Ssid, pos, sec_len); /* DBG_871X("%s COMBO_SCAN with specific ssid:%s, %d\n", __func__ */ /* , ssid[ssid_index].Ssid, ssid[ssid_index].SsidLength); */ ssid_index++; diff --git a/include/crypto/blake2s.h b/include/crypto/blake2s.h index b471deac28ff8..4e30e1799e614 100644 --- a/include/crypto/blake2s.h +++ b/include/crypto/blake2s.h @@ -3,15 +3,14 @@ * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. */ -#ifndef BLAKE2S_H -#define BLAKE2S_H +#ifndef _CRYPTO_BLAKE2S_H +#define _CRYPTO_BLAKE2S_H +#include #include #include #include -#include - enum blake2s_lengths { BLAKE2S_BLOCK_SIZE = 64, BLAKE2S_HASH_SIZE = 32, @@ -24,6 +23,7 @@ enum blake2s_lengths { }; struct blake2s_state { + /* 'h', 't', and 'f' are used in assembly code, so keep them as-is. */ u32 h[8]; u32 t[2]; u32 f[2]; @@ -43,29 +43,34 @@ enum blake2s_iv { BLAKE2S_IV7 = 0x5BE0CD19UL, }; -void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen); -void blake2s_final(struct blake2s_state *state, u8 *out); - -static inline void blake2s_init_param(struct blake2s_state *state, - const u32 param) +static inline void __blake2s_init(struct blake2s_state *state, size_t outlen, + const void *key, size_t keylen) { - *state = (struct blake2s_state){{ - BLAKE2S_IV0 ^ param, - BLAKE2S_IV1, - BLAKE2S_IV2, - BLAKE2S_IV3, - BLAKE2S_IV4, - BLAKE2S_IV5, - BLAKE2S_IV6, - BLAKE2S_IV7, - }}; + state->h[0] = BLAKE2S_IV0 ^ (0x01010000 | keylen << 8 | outlen); + state->h[1] = BLAKE2S_IV1; + state->h[2] = BLAKE2S_IV2; + state->h[3] = BLAKE2S_IV3; + state->h[4] = BLAKE2S_IV4; + state->h[5] = BLAKE2S_IV5; + state->h[6] = BLAKE2S_IV6; + state->h[7] = BLAKE2S_IV7; + state->t[0] = 0; + state->t[1] = 0; + state->f[0] = 0; + state->f[1] = 0; + state->buflen = 0; + state->outlen = outlen; + if (keylen) { + memcpy(state->buf, key, keylen); + memset(&state->buf[keylen], 0, BLAKE2S_BLOCK_SIZE - keylen); + state->buflen = BLAKE2S_BLOCK_SIZE; + } } static inline void blake2s_init(struct blake2s_state *state, const size_t outlen) { - blake2s_init_param(state, 0x01010000 | outlen); - state->outlen = outlen; + __blake2s_init(state, outlen, NULL, 0); } static inline void blake2s_init_key(struct blake2s_state *state, @@ -75,12 +80,12 @@ static inline void blake2s_init_key(struct blake2s_state *state, WARN_ON(IS_ENABLED(DEBUG) && (!outlen || outlen > BLAKE2S_HASH_SIZE || !key || !keylen || keylen > BLAKE2S_KEY_SIZE)); - blake2s_init_param(state, 0x01010000 | keylen << 8 | outlen); - memcpy(state->buf, key, keylen); - state->buflen = BLAKE2S_BLOCK_SIZE; - state->outlen = outlen; + __blake2s_init(state, outlen, key, keylen); } +void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen); +void blake2s_final(struct blake2s_state *state, u8 *out); + static inline void blake2s(u8 *out, const u8 *in, const u8 *key, const size_t outlen, const size_t inlen, const size_t keylen) @@ -91,16 +96,9 @@ static inline void blake2s(u8 *out, const u8 *in, const u8 *key, outlen > BLAKE2S_HASH_SIZE || keylen > BLAKE2S_KEY_SIZE || (!key && keylen))); - if (keylen) - blake2s_init_key(&state, outlen, key, keylen); - else - blake2s_init(&state, outlen); - + __blake2s_init(&state, outlen, key, keylen); blake2s_update(&state, in, inlen); blake2s_final(&state, out); } -void blake2s256_hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen, - const size_t keylen); - -#endif /* BLAKE2S_H */ +#endif /* _CRYPTO_BLAKE2S_H */ diff --git a/include/crypto/chacha.h b/include/crypto/chacha.h index dabaee6987186..b3ea73b819443 100644 --- a/include/crypto/chacha.h +++ b/include/crypto/chacha.h @@ -47,12 +47,19 @@ static inline void hchacha_block(const u32 *state, u32 *out, int nrounds) hchacha_block_generic(state, out, nrounds); } +enum chacha_constants { /* expand 32-byte k */ + CHACHA_CONSTANT_EXPA = 0x61707865U, + CHACHA_CONSTANT_ND_3 = 0x3320646eU, + CHACHA_CONSTANT_2_BY = 0x79622d32U, + CHACHA_CONSTANT_TE_K = 0x6b206574U +}; + static inline void chacha_init_consts(u32 *state) { - state[0] = 0x61707865; /* "expa" */ - state[1] = 0x3320646e; /* "nd 3" */ - state[2] = 0x79622d32; /* "2-by" */ - state[3] = 0x6b206574; /* "te k" */ + state[0] = CHACHA_CONSTANT_EXPA; + state[1] = CHACHA_CONSTANT_ND_3; + state[2] = CHACHA_CONSTANT_2_BY; + state[3] = CHACHA_CONSTANT_TE_K; } void chacha_init_arch(u32 *state, const u32 *key, const u8 *iv); diff --git a/include/crypto/drbg.h b/include/crypto/drbg.h index c4165126937e4..88e4d145f7cda 100644 --- a/include/crypto/drbg.h +++ b/include/crypto/drbg.h @@ -136,7 +136,7 @@ struct drbg_state { const struct drbg_state_ops *d_ops; const struct drbg_core *core; struct drbg_string test_data; - struct random_ready_callback random_ready; + struct notifier_block random_ready; }; static inline __u8 drbg_statelen(struct drbg_state *drbg) diff --git a/include/crypto/internal/blake2s.h b/include/crypto/internal/blake2s.h index 74ff77032e526..52363eee2b20e 100644 --- a/include/crypto/internal/blake2s.h +++ b/include/crypto/internal/blake2s.h @@ -1,24 +1,129 @@ /* SPDX-License-Identifier: GPL-2.0 OR MIT */ +/* + * Helper functions for BLAKE2s implementations. + * Keep this in sync with the corresponding BLAKE2b header. + */ -#ifndef BLAKE2S_INTERNAL_H -#define BLAKE2S_INTERNAL_H +#ifndef _CRYPTO_INTERNAL_BLAKE2S_H +#define _CRYPTO_INTERNAL_BLAKE2S_H #include +#include +#include + +void blake2s_compress_generic(struct blake2s_state *state, const u8 *block, + size_t nblocks, const u32 inc); + +void blake2s_compress(struct blake2s_state *state, const u8 *block, + size_t nblocks, const u32 inc); + +bool blake2s_selftest(void); + +static inline void blake2s_set_lastblock(struct blake2s_state *state) +{ + state->f[0] = -1; +} + +/* Helper functions for BLAKE2s shared by the library and shash APIs */ + +static __always_inline void +__blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen, + bool force_generic) +{ + const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen; + + if (unlikely(!inlen)) + return; + if (inlen > fill) { + memcpy(state->buf + state->buflen, in, fill); + if (force_generic) + blake2s_compress_generic(state, state->buf, 1, + BLAKE2S_BLOCK_SIZE); + else + blake2s_compress(state, state->buf, 1, + BLAKE2S_BLOCK_SIZE); + state->buflen = 0; + in += fill; + inlen -= fill; + } + if (inlen > BLAKE2S_BLOCK_SIZE) { + const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE); + /* Hash one less (full) block than strictly possible */ + if (force_generic) + blake2s_compress_generic(state, in, nblocks - 1, + BLAKE2S_BLOCK_SIZE); + else + blake2s_compress(state, in, nblocks - 1, + BLAKE2S_BLOCK_SIZE); + in += BLAKE2S_BLOCK_SIZE * (nblocks - 1); + inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1); + } + memcpy(state->buf + state->buflen, in, inlen); + state->buflen += inlen; +} + +static __always_inline void +__blake2s_final(struct blake2s_state *state, u8 *out, bool force_generic) +{ + blake2s_set_lastblock(state); + memset(state->buf + state->buflen, 0, + BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */ + if (force_generic) + blake2s_compress_generic(state, state->buf, 1, state->buflen); + else + blake2s_compress(state, state->buf, 1, state->buflen); + cpu_to_le32_array(state->h, ARRAY_SIZE(state->h)); + memcpy(out, state->h, state->outlen); +} + +/* Helper functions for shash implementations of BLAKE2s */ struct blake2s_tfm_ctx { u8 key[BLAKE2S_KEY_SIZE]; unsigned int keylen; }; -void blake2s_compress_generic(struct blake2s_state *state,const u8 *block, - size_t nblocks, const u32 inc); +static inline int crypto_blake2s_setkey(struct crypto_shash *tfm, + const u8 *key, unsigned int keylen) +{ + struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(tfm); -void blake2s_compress_arch(struct blake2s_state *state,const u8 *block, - size_t nblocks, const u32 inc); + if (keylen == 0 || keylen > BLAKE2S_KEY_SIZE) + return -EINVAL; -static inline void blake2s_set_lastblock(struct blake2s_state *state) + memcpy(tctx->key, key, keylen); + tctx->keylen = keylen; + + return 0; +} + +static inline int crypto_blake2s_init(struct shash_desc *desc) { - state->f[0] = -1; + const struct blake2s_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm); + struct blake2s_state *state = shash_desc_ctx(desc); + unsigned int outlen = crypto_shash_digestsize(desc->tfm); + + __blake2s_init(state, outlen, tctx->key, tctx->keylen); + return 0; +} + +static inline int crypto_blake2s_update(struct shash_desc *desc, + const u8 *in, unsigned int inlen, + bool force_generic) +{ + struct blake2s_state *state = shash_desc_ctx(desc); + + __blake2s_update(state, in, inlen, force_generic); + return 0; +} + +static inline int crypto_blake2s_final(struct shash_desc *desc, u8 *out, + bool force_generic) +{ + struct blake2s_state *state = shash_desc_ctx(desc); + + __blake2s_final(state, out, force_generic); + return 0; } -#endif /* BLAKE2S_INTERNAL_H */ +#endif /* _CRYPTO_INTERNAL_BLAKE2S_H */ diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 8fb893ed205e3..fc945f9df2c1d 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -61,6 +61,7 @@ enum cpuhp_state { CPUHP_LUSTRE_CFS_DEAD, CPUHP_AP_ARM_CACHE_B15_RAC_DEAD, CPUHP_PADATA_DEAD, + CPUHP_RANDOM_PREPARE, CPUHP_WORKQUEUE_PREP, CPUHP_POWER_NUMA_PREPARE, CPUHP_HRTIMERS_PREPARE, @@ -187,6 +188,7 @@ enum cpuhp_state { CPUHP_AP_PERF_POWERPC_HV_GPCI_ONLINE, CPUHP_AP_WATCHDOG_ONLINE, CPUHP_AP_WORKQUEUE_ONLINE, + CPUHP_AP_RANDOM_ONLINE, CPUHP_AP_RCUTREE_ONLINE, CPUHP_AP_BASE_CACHEINFO_ONLINE, CPUHP_AP_ONLINE_DYN, diff --git a/include/linux/hw_random.h b/include/linux/hw_random.h index 8e6dd908da216..aa1d4da03538b 100644 --- a/include/linux/hw_random.h +++ b/include/linux/hw_random.h @@ -60,7 +60,5 @@ extern int devm_hwrng_register(struct device *dev, struct hwrng *rng); /** Unregister a Hardware Random Number Generator driver. */ extern void hwrng_unregister(struct hwrng *rng); extern void devm_hwrng_unregister(struct device *dve, struct hwrng *rng); -/** Feed random bits into the pool. */ -extern void add_hwgenerator_randomness(const char *buffer, size_t count, size_t entropy); #endif /* LINUX_HWRANDOM_H_ */ diff --git a/include/linux/mm.h b/include/linux/mm.h index 289c26f055cdd..5b4d88faf114a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2585,6 +2585,7 @@ extern int install_special_mapping(struct mm_struct *mm, unsigned long flags, struct page **pages); unsigned long randomize_stack_top(unsigned long stack_top); +unsigned long randomize_page(unsigned long start, unsigned long range); extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long); diff --git a/include/linux/prandom.h b/include/linux/prandom.h index 056d31317e499..a4aadd2dc153e 100644 --- a/include/linux/prandom.h +++ b/include/linux/prandom.h @@ -10,6 +10,7 @@ #include #include +#include u32 prandom_u32(void); void prandom_bytes(void *buf, size_t nbytes); @@ -27,15 +28,10 @@ DECLARE_PER_CPU(unsigned long, net_rand_noise); * The core SipHash round function. Each line can be executed in * parallel given enough CPU resources. */ -#define PRND_SIPROUND(v0, v1, v2, v3) ( \ - v0 += v1, v1 = rol64(v1, 13), v2 += v3, v3 = rol64(v3, 16), \ - v1 ^= v0, v0 = rol64(v0, 32), v3 ^= v2, \ - v0 += v3, v3 = rol64(v3, 21), v2 += v1, v1 = rol64(v1, 17), \ - v3 ^= v0, v1 ^= v2, v2 = rol64(v2, 32) \ -) +#define PRND_SIPROUND(v0, v1, v2, v3) SIPHASH_PERMUTATION(v0, v1, v2, v3) -#define PRND_K0 (0x736f6d6570736575 ^ 0x6c7967656e657261) -#define PRND_K1 (0x646f72616e646f6d ^ 0x7465646279746573) +#define PRND_K0 (SIPHASH_CONST_0 ^ SIPHASH_CONST_2) +#define PRND_K1 (SIPHASH_CONST_1 ^ SIPHASH_CONST_3) #elif BITS_PER_LONG == 32 /* @@ -43,14 +39,9 @@ DECLARE_PER_CPU(unsigned long, net_rand_noise); * This is weaker, but 32-bit machines are not used for high-traffic * applications, so there is less output for an attacker to analyze. */ -#define PRND_SIPROUND(v0, v1, v2, v3) ( \ - v0 += v1, v1 = rol32(v1, 5), v2 += v3, v3 = rol32(v3, 8), \ - v1 ^= v0, v0 = rol32(v0, 16), v3 ^= v2, \ - v0 += v3, v3 = rol32(v3, 7), v2 += v1, v1 = rol32(v1, 13), \ - v3 ^= v0, v1 ^= v2, v2 = rol32(v2, 16) \ -) -#define PRND_K0 0x6c796765 -#define PRND_K1 0x74656462 +#define PRND_SIPROUND(v0, v1, v2, v3) HSIPHASH_PERMUTATION(v0, v1, v2, v3) +#define PRND_K0 (HSIPHASH_CONST_0 ^ HSIPHASH_CONST_2) +#define PRND_K1 (HSIPHASH_CONST_1 ^ HSIPHASH_CONST_3) #else #error Unsupported BITS_PER_LONG diff --git a/include/linux/random.h b/include/linux/random.h index f45b8be3e3c4e..917470c4490ac 100644 --- a/include/linux/random.h +++ b/include/linux/random.h @@ -1,9 +1,5 @@ /* SPDX-License-Identifier: GPL-2.0 */ -/* - * include/linux/random.h - * - * Include file for the random number generator. - */ + #ifndef _LINUX_RANDOM_H #define _LINUX_RANDOM_H @@ -14,41 +10,26 @@ #include -struct random_ready_callback { - struct list_head list; - void (*func)(struct random_ready_callback *rdy); - struct module *owner; -}; +struct notifier_block; -extern void add_device_randomness(const void *, unsigned int); -extern void add_bootloader_randomness(const void *, unsigned int); +void add_device_randomness(const void *buf, size_t len); +void add_bootloader_randomness(const void *buf, size_t len); +void add_input_randomness(unsigned int type, unsigned int code, + unsigned int value) __latent_entropy; +void add_interrupt_randomness(int irq) __latent_entropy; +void add_hwgenerator_randomness(const void *buf, size_t len, size_t entropy); #if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__) static inline void add_latent_entropy(void) { - add_device_randomness((const void *)&latent_entropy, - sizeof(latent_entropy)); + add_device_randomness((const void *)&latent_entropy, sizeof(latent_entropy)); } #else -static inline void add_latent_entropy(void) {} -#endif - -extern void add_input_randomness(unsigned int type, unsigned int code, - unsigned int value) __latent_entropy; -extern void add_interrupt_randomness(int irq, int irq_flags) __latent_entropy; - -extern void get_random_bytes(void *buf, int nbytes); -extern int wait_for_random_bytes(void); -extern int __init rand_initialize(void); -extern bool rng_is_initialized(void); -extern int add_random_ready_callback(struct random_ready_callback *rdy); -extern void del_random_ready_callback(struct random_ready_callback *rdy); -extern int __must_check get_random_bytes_arch(void *buf, int nbytes); - -#ifndef MODULE -extern const struct file_operations random_fops, urandom_fops; +static inline void add_latent_entropy(void) { } #endif +void get_random_bytes(void *buf, size_t len); +size_t __must_check get_random_bytes_arch(void *buf, size_t len); u32 get_random_u32(void); u64 get_random_u64(void); static inline unsigned int get_random_int(void) @@ -80,36 +61,38 @@ static inline unsigned long get_random_long(void) static inline unsigned long get_random_canary(void) { - unsigned long val = get_random_long(); - - return val & CANARY_MASK; + return get_random_long() & CANARY_MASK; } +int __init random_init(const char *command_line); +bool rng_is_initialized(void); +int wait_for_random_bytes(void); +int register_random_ready_notifier(struct notifier_block *nb); +int unregister_random_ready_notifier(struct notifier_block *nb); + /* Calls wait_for_random_bytes() and then calls get_random_bytes(buf, nbytes). * Returns the result of the call to wait_for_random_bytes. */ -static inline int get_random_bytes_wait(void *buf, int nbytes) +static inline int get_random_bytes_wait(void *buf, size_t nbytes) { int ret = wait_for_random_bytes(); get_random_bytes(buf, nbytes); return ret; } -#define declare_get_random_var_wait(var) \ - static inline int get_random_ ## var ## _wait(var *out) { \ +#define declare_get_random_var_wait(name, ret_type) \ + static inline int get_random_ ## name ## _wait(ret_type *out) { \ int ret = wait_for_random_bytes(); \ if (unlikely(ret)) \ return ret; \ - *out = get_random_ ## var(); \ + *out = get_random_ ## name(); \ return 0; \ } -declare_get_random_var_wait(u32) -declare_get_random_var_wait(u64) -declare_get_random_var_wait(int) -declare_get_random_var_wait(long) +declare_get_random_var_wait(u32, u32) +declare_get_random_var_wait(u64, u32) +declare_get_random_var_wait(int, unsigned int) +declare_get_random_var_wait(long, unsigned long) #undef declare_get_random_var -unsigned long randomize_page(unsigned long start, unsigned long range); - /* * This is designed to be standalone for just prandom * users, but for now we include it from @@ -120,22 +103,10 @@ unsigned long randomize_page(unsigned long start, unsigned long range); #ifdef CONFIG_ARCH_RANDOM # include #else -static inline bool __must_check arch_get_random_long(unsigned long *v) -{ - return false; -} -static inline bool __must_check arch_get_random_int(unsigned int *v) -{ - return false; -} -static inline bool __must_check arch_get_random_seed_long(unsigned long *v) -{ - return false; -} -static inline bool __must_check arch_get_random_seed_int(unsigned int *v) -{ - return false; -} +static inline bool __must_check arch_get_random_long(unsigned long *v) { return false; } +static inline bool __must_check arch_get_random_int(unsigned int *v) { return false; } +static inline bool __must_check arch_get_random_seed_long(unsigned long *v) { return false; } +static inline bool __must_check arch_get_random_seed_int(unsigned int *v) { return false; } #endif /* @@ -158,4 +129,13 @@ static inline bool __init arch_get_random_long_early(unsigned long *v) } #endif +#ifdef CONFIG_SMP +int random_prepare_cpu(unsigned int cpu); +int random_online_cpu(unsigned int cpu); +#endif + +#ifndef MODULE +extern const struct file_operations random_fops, urandom_fops; +#endif + #endif /* _LINUX_RANDOM_H */ diff --git a/include/linux/security.h b/include/linux/security.h index 35355429648e3..330029ef7e894 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -121,10 +121,12 @@ enum lockdown_reason { LOCKDOWN_DEBUGFS, LOCKDOWN_XMON_WR, LOCKDOWN_BPF_WRITE_USER, + LOCKDOWN_DBG_WRITE_KERNEL, LOCKDOWN_INTEGRITY_MAX, LOCKDOWN_KCORE, LOCKDOWN_KPROBES, LOCKDOWN_BPF_READ, + LOCKDOWN_DBG_READ_KERNEL, LOCKDOWN_PERF, LOCKDOWN_TRACEFS, LOCKDOWN_XMON_RW, diff --git a/include/linux/siphash.h b/include/linux/siphash.h index 0cda61855d907..0bb5ecd507bef 100644 --- a/include/linux/siphash.h +++ b/include/linux/siphash.h @@ -136,4 +136,32 @@ static inline u32 hsiphash(const void *data, size_t len, return ___hsiphash_aligned(data, len, key); } +/* + * These macros expose the raw SipHash and HalfSipHash permutations. + * Do not use them directly! If you think you have a use for them, + * be sure to CC the maintainer of this file explaining why. + */ + +#define SIPHASH_PERMUTATION(a, b, c, d) ( \ + (a) += (b), (b) = rol64((b), 13), (b) ^= (a), (a) = rol64((a), 32), \ + (c) += (d), (d) = rol64((d), 16), (d) ^= (c), \ + (a) += (d), (d) = rol64((d), 21), (d) ^= (a), \ + (c) += (b), (b) = rol64((b), 17), (b) ^= (c), (c) = rol64((c), 32)) + +#define SIPHASH_CONST_0 0x736f6d6570736575ULL +#define SIPHASH_CONST_1 0x646f72616e646f6dULL +#define SIPHASH_CONST_2 0x6c7967656e657261ULL +#define SIPHASH_CONST_3 0x7465646279746573ULL + +#define HSIPHASH_PERMUTATION(a, b, c, d) ( \ + (a) += (b), (b) = rol32((b), 5), (b) ^= (a), (a) = rol32((a), 16), \ + (c) += (d), (d) = rol32((d), 8), (d) ^= (c), \ + (a) += (d), (d) = rol32((d), 7), (d) ^= (a), \ + (c) += (b), (b) = rol32((b), 13), (b) ^= (c), (c) = rol32((c), 16)) + +#define HSIPHASH_CONST_0 0U +#define HSIPHASH_CONST_1 0U +#define HSIPHASH_CONST_2 0x6c796765U +#define HSIPHASH_CONST_3 0x74656462U + #endif /* _LINUX_SIPHASH_H */ diff --git a/include/linux/timex.h b/include/linux/timex.h index ce08597636705..2efab9a806a9d 100644 --- a/include/linux/timex.h +++ b/include/linux/timex.h @@ -62,6 +62,8 @@ #include #include +unsigned long random_get_entropy_fallback(void); + #include #ifndef random_get_entropy @@ -74,8 +76,14 @@ * * By default we use get_cycles() for this purpose, but individual * architectures may override this in their asm/timex.h header file. + * If a given arch does not have get_cycles(), then we fallback to + * using random_get_entropy_fallback(). */ -#define random_get_entropy() get_cycles() +#ifdef get_cycles +#define random_get_entropy() ((unsigned long)get_cycles()) +#else +#define random_get_entropy() random_get_entropy_fallback() +#endif #endif /* diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h index ca6a3ea9057ec..d4d611064a76f 100644 --- a/include/net/inet_hashtables.h +++ b/include/net/inet_hashtables.h @@ -419,7 +419,7 @@ static inline void sk_rcv_saddr_set(struct sock *sk, __be32 addr) } int __inet_hash_connect(struct inet_timewait_death_row *death_row, - struct sock *sk, u32 port_offset, + struct sock *sk, u64 port_offset, int (*check_established)(struct inet_timewait_death_row *, struct sock *, __u16, struct inet_timewait_sock **)); diff --git a/include/net/secure_seq.h b/include/net/secure_seq.h index d7d2495f83c27..dac91aa38c5af 100644 --- a/include/net/secure_seq.h +++ b/include/net/secure_seq.h @@ -4,8 +4,8 @@ #include -u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport); -u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, +u64 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport); +u64 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, __be16 dport); u32 secure_tcp_seq(__be32 saddr, __be32 daddr, __be16 sport, __be16 dport); diff --git a/include/trace/events/random.h b/include/trace/events/random.h deleted file mode 100644 index 9570a10cb949b..0000000000000 --- a/include/trace/events/random.h +++ /dev/null @@ -1,330 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#undef TRACE_SYSTEM -#define TRACE_SYSTEM random - -#if !defined(_TRACE_RANDOM_H) || defined(TRACE_HEADER_MULTI_READ) -#define _TRACE_RANDOM_H - -#include -#include - -TRACE_EVENT(add_device_randomness, - TP_PROTO(int bytes, unsigned long IP), - - TP_ARGS(bytes, IP), - - TP_STRUCT__entry( - __field( int, bytes ) - __field(unsigned long, IP ) - ), - - TP_fast_assign( - __entry->bytes = bytes; - __entry->IP = IP; - ), - - TP_printk("bytes %d caller %pS", - __entry->bytes, (void *)__entry->IP) -); - -DECLARE_EVENT_CLASS(random__mix_pool_bytes, - TP_PROTO(const char *pool_name, int bytes, unsigned long IP), - - TP_ARGS(pool_name, bytes, IP), - - TP_STRUCT__entry( - __field( const char *, pool_name ) - __field( int, bytes ) - __field(unsigned long, IP ) - ), - - TP_fast_assign( - __entry->pool_name = pool_name; - __entry->bytes = bytes; - __entry->IP = IP; - ), - - TP_printk("%s pool: bytes %d caller %pS", - __entry->pool_name, __entry->bytes, (void *)__entry->IP) -); - -DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes, - TP_PROTO(const char *pool_name, int bytes, unsigned long IP), - - TP_ARGS(pool_name, bytes, IP) -); - -DEFINE_EVENT(random__mix_pool_bytes, mix_pool_bytes_nolock, - TP_PROTO(const char *pool_name, int bytes, unsigned long IP), - - TP_ARGS(pool_name, bytes, IP) -); - -TRACE_EVENT(credit_entropy_bits, - TP_PROTO(const char *pool_name, int bits, int entropy_count, - unsigned long IP), - - TP_ARGS(pool_name, bits, entropy_count, IP), - - TP_STRUCT__entry( - __field( const char *, pool_name ) - __field( int, bits ) - __field( int, entropy_count ) - __field(unsigned long, IP ) - ), - - TP_fast_assign( - __entry->pool_name = pool_name; - __entry->bits = bits; - __entry->entropy_count = entropy_count; - __entry->IP = IP; - ), - - TP_printk("%s pool: bits %d entropy_count %d caller %pS", - __entry->pool_name, __entry->bits, - __entry->entropy_count, (void *)__entry->IP) -); - -TRACE_EVENT(push_to_pool, - TP_PROTO(const char *pool_name, int pool_bits, int input_bits), - - TP_ARGS(pool_name, pool_bits, input_bits), - - TP_STRUCT__entry( - __field( const char *, pool_name ) - __field( int, pool_bits ) - __field( int, input_bits ) - ), - - TP_fast_assign( - __entry->pool_name = pool_name; - __entry->pool_bits = pool_bits; - __entry->input_bits = input_bits; - ), - - TP_printk("%s: pool_bits %d input_pool_bits %d", - __entry->pool_name, __entry->pool_bits, - __entry->input_bits) -); - -TRACE_EVENT(debit_entropy, - TP_PROTO(const char *pool_name, int debit_bits), - - TP_ARGS(pool_name, debit_bits), - - TP_STRUCT__entry( - __field( const char *, pool_name ) - __field( int, debit_bits ) - ), - - TP_fast_assign( - __entry->pool_name = pool_name; - __entry->debit_bits = debit_bits; - ), - - TP_printk("%s: debit_bits %d", __entry->pool_name, - __entry->debit_bits) -); - -TRACE_EVENT(add_input_randomness, - TP_PROTO(int input_bits), - - TP_ARGS(input_bits), - - TP_STRUCT__entry( - __field( int, input_bits ) - ), - - TP_fast_assign( - __entry->input_bits = input_bits; - ), - - TP_printk("input_pool_bits %d", __entry->input_bits) -); - -TRACE_EVENT(add_disk_randomness, - TP_PROTO(dev_t dev, int input_bits), - - TP_ARGS(dev, input_bits), - - TP_STRUCT__entry( - __field( dev_t, dev ) - __field( int, input_bits ) - ), - - TP_fast_assign( - __entry->dev = dev; - __entry->input_bits = input_bits; - ), - - TP_printk("dev %d,%d input_pool_bits %d", MAJOR(__entry->dev), - MINOR(__entry->dev), __entry->input_bits) -); - -TRACE_EVENT(xfer_secondary_pool, - TP_PROTO(const char *pool_name, int xfer_bits, int request_bits, - int pool_entropy, int input_entropy), - - TP_ARGS(pool_name, xfer_bits, request_bits, pool_entropy, - input_entropy), - - TP_STRUCT__entry( - __field( const char *, pool_name ) - __field( int, xfer_bits ) - __field( int, request_bits ) - __field( int, pool_entropy ) - __field( int, input_entropy ) - ), - - TP_fast_assign( - __entry->pool_name = pool_name; - __entry->xfer_bits = xfer_bits; - __entry->request_bits = request_bits; - __entry->pool_entropy = pool_entropy; - __entry->input_entropy = input_entropy; - ), - - TP_printk("pool %s xfer_bits %d request_bits %d pool_entropy %d " - "input_entropy %d", __entry->pool_name, __entry->xfer_bits, - __entry->request_bits, __entry->pool_entropy, - __entry->input_entropy) -); - -DECLARE_EVENT_CLASS(random__get_random_bytes, - TP_PROTO(int nbytes, unsigned long IP), - - TP_ARGS(nbytes, IP), - - TP_STRUCT__entry( - __field( int, nbytes ) - __field(unsigned long, IP ) - ), - - TP_fast_assign( - __entry->nbytes = nbytes; - __entry->IP = IP; - ), - - TP_printk("nbytes %d caller %pS", __entry->nbytes, (void *)__entry->IP) -); - -DEFINE_EVENT(random__get_random_bytes, get_random_bytes, - TP_PROTO(int nbytes, unsigned long IP), - - TP_ARGS(nbytes, IP) -); - -DEFINE_EVENT(random__get_random_bytes, get_random_bytes_arch, - TP_PROTO(int nbytes, unsigned long IP), - - TP_ARGS(nbytes, IP) -); - -DECLARE_EVENT_CLASS(random__extract_entropy, - TP_PROTO(const char *pool_name, int nbytes, int entropy_count, - unsigned long IP), - - TP_ARGS(pool_name, nbytes, entropy_count, IP), - - TP_STRUCT__entry( - __field( const char *, pool_name ) - __field( int, nbytes ) - __field( int, entropy_count ) - __field(unsigned long, IP ) - ), - - TP_fast_assign( - __entry->pool_name = pool_name; - __entry->nbytes = nbytes; - __entry->entropy_count = entropy_count; - __entry->IP = IP; - ), - - TP_printk("%s pool: nbytes %d entropy_count %d caller %pS", - __entry->pool_name, __entry->nbytes, __entry->entropy_count, - (void *)__entry->IP) -); - - -DEFINE_EVENT(random__extract_entropy, extract_entropy, - TP_PROTO(const char *pool_name, int nbytes, int entropy_count, - unsigned long IP), - - TP_ARGS(pool_name, nbytes, entropy_count, IP) -); - -DEFINE_EVENT(random__extract_entropy, extract_entropy_user, - TP_PROTO(const char *pool_name, int nbytes, int entropy_count, - unsigned long IP), - - TP_ARGS(pool_name, nbytes, entropy_count, IP) -); - -TRACE_EVENT(random_read, - TP_PROTO(int got_bits, int need_bits, int pool_left, int input_left), - - TP_ARGS(got_bits, need_bits, pool_left, input_left), - - TP_STRUCT__entry( - __field( int, got_bits ) - __field( int, need_bits ) - __field( int, pool_left ) - __field( int, input_left ) - ), - - TP_fast_assign( - __entry->got_bits = got_bits; - __entry->need_bits = need_bits; - __entry->pool_left = pool_left; - __entry->input_left = input_left; - ), - - TP_printk("got_bits %d still_needed_bits %d " - "blocking_pool_entropy_left %d input_entropy_left %d", - __entry->got_bits, __entry->got_bits, __entry->pool_left, - __entry->input_left) -); - -TRACE_EVENT(urandom_read, - TP_PROTO(int got_bits, int pool_left, int input_left), - - TP_ARGS(got_bits, pool_left, input_left), - - TP_STRUCT__entry( - __field( int, got_bits ) - __field( int, pool_left ) - __field( int, input_left ) - ), - - TP_fast_assign( - __entry->got_bits = got_bits; - __entry->pool_left = pool_left; - __entry->input_left = input_left; - ), - - TP_printk("got_bits %d nonblocking_pool_entropy_left %d " - "input_entropy_left %d", __entry->got_bits, - __entry->pool_left, __entry->input_left) -); - -TRACE_EVENT(prandom_u32, - - TP_PROTO(unsigned int ret), - - TP_ARGS(ret), - - TP_STRUCT__entry( - __field( unsigned int, ret) - ), - - TP_fast_assign( - __entry->ret = ret; - ), - - TP_printk("ret=%u" , __entry->ret) -); - -#endif /* _TRACE_RANDOM_H */ - -/* This part must be outside protection */ -#include diff --git a/init/main.c b/init/main.c index 3526eaec7508f..d8bfe61b5a889 100644 --- a/init/main.c +++ b/init/main.c @@ -952,21 +952,18 @@ asmlinkage __visible void __init __no_sanitize_address start_kernel(void) hrtimers_init(); softirq_init(); timekeeping_init(); + time_init(); /* * For best initial stack canary entropy, prepare it after: * - setup_arch() for any UEFI RNG entropy and boot cmdline access - * - timekeeping_init() for ktime entropy used in rand_initialize() - * - rand_initialize() to get any arch-specific entropy like RDRAND - * - add_latent_entropy() to get any latent entropy - * - adding command line entropy + * - timekeeping_init() for ktime entropy used in random_init() + * - time_init() for making random_get_entropy() work on some platforms + * - random_init() to initialize the RNG from from early entropy sources */ - rand_initialize(); - add_latent_entropy(); - add_device_randomness(command_line, strlen(command_line)); + random_init(command_line); boot_init_stack_canary(); - time_init(); perf_event_init(); profile_init(); call_function_init(); diff --git a/kernel/cpu.c b/kernel/cpu.c index c06ced18f78ad..3c9ee966c56a5 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #define CREATE_TRACE_POINTS @@ -1581,6 +1582,11 @@ static struct cpuhp_step cpuhp_hp_states[] = { .startup.single = perf_event_init_cpu, .teardown.single = perf_event_exit_cpu, }, + [CPUHP_RANDOM_PREPARE] = { + .name = "random:prepare", + .startup.single = random_prepare_cpu, + .teardown.single = NULL, + }, [CPUHP_WORKQUEUE_PREP] = { .name = "workqueue:prepare", .startup.single = workqueue_prepare_cpu, @@ -1697,6 +1703,11 @@ static struct cpuhp_step cpuhp_hp_states[] = { .startup.single = workqueue_online_cpu, .teardown.single = workqueue_offline_cpu, }, + [CPUHP_AP_RANDOM_ONLINE] = { + .name = "random:online", + .startup.single = random_online_cpu, + .teardown.single = NULL, + }, [CPUHP_AP_RCUTREE_ONLINE] = { .name = "RCU/tree:online", .startup.single = rcutree_online_cpu, diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 8661eb2b17711..0f31b22abe8d9 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -56,6 +56,7 @@ #include #include #include +#include #include #include @@ -756,6 +757,29 @@ cpu_master_loop: continue; kgdb_connected = 0; } else { + /* + * This is a brutal way to interfere with the debugger + * and prevent gdb being used to poke at kernel memory. + * This could cause trouble if lockdown is applied when + * there is already an active gdb session. For now the + * answer is simply "don't do that". Typically lockdown + * *will* be applied before the debug core gets started + * so only developers using kgdb for fairly advanced + * early kernel debug can be biten by this. Hopefully + * they are sophisticated enough to take care of + * themselves, especially with help from the lockdown + * message printed on the console! + */ + if (security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL)) { + if (IS_ENABLED(CONFIG_KGDB_KDB)) { + /* Switch back to kdb if possible... */ + dbg_kdb_mode = 1; + continue; + } else { + /* ... otherwise just bail */ + break; + } + } error = gdb_serial_stub(ks); } diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 930ac1b25ec7c..4e09fab52faf5 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -45,6 +45,7 @@ #include #include #include +#include #include "kdb_private.h" #undef MODULE_PARAM_PREFIX @@ -197,10 +198,62 @@ struct task_struct *kdb_curr_task(int cpu) } /* - * Check whether the flags of the current command and the permissions - * of the kdb console has allow a command to be run. + * Update the permissions flags (kdb_cmd_enabled) to match the + * current lockdown state. + * + * Within this function the calls to security_locked_down() are "lazy". We + * avoid calling them if the current value of kdb_cmd_enabled already excludes + * flags that might be subject to lockdown. Additionally we deliberately check + * the lockdown flags independently (even though read lockdown implies write + * lockdown) since that results in both simpler code and clearer messages to + * the user on first-time debugger entry. + * + * The permission masks during a read+write lockdown permits the following + * flags: INSPECT, SIGNAL, REBOOT (and ALWAYS_SAFE). + * + * The INSPECT commands are not blocked during lockdown because they are + * not arbitrary memory reads. INSPECT covers the backtrace family (sometimes + * forcing them to have no arguments) and lsmod. These commands do expose + * some kernel state but do not allow the developer seated at the console to + * choose what state is reported. SIGNAL and REBOOT should not be controversial, + * given these are allowed for root during lockdown already. + */ +static void kdb_check_for_lockdown(void) +{ + const int write_flags = KDB_ENABLE_MEM_WRITE | + KDB_ENABLE_REG_WRITE | + KDB_ENABLE_FLOW_CTRL; + const int read_flags = KDB_ENABLE_MEM_READ | + KDB_ENABLE_REG_READ; + + bool need_to_lockdown_write = false; + bool need_to_lockdown_read = false; + + if (kdb_cmd_enabled & (KDB_ENABLE_ALL | write_flags)) + need_to_lockdown_write = + security_locked_down(LOCKDOWN_DBG_WRITE_KERNEL); + + if (kdb_cmd_enabled & (KDB_ENABLE_ALL | read_flags)) + need_to_lockdown_read = + security_locked_down(LOCKDOWN_DBG_READ_KERNEL); + + /* De-compose KDB_ENABLE_ALL if required */ + if (need_to_lockdown_write || need_to_lockdown_read) + if (kdb_cmd_enabled & KDB_ENABLE_ALL) + kdb_cmd_enabled = KDB_ENABLE_MASK & ~KDB_ENABLE_ALL; + + if (need_to_lockdown_write) + kdb_cmd_enabled &= ~write_flags; + + if (need_to_lockdown_read) + kdb_cmd_enabled &= ~read_flags; +} + +/* + * Check whether the flags of the current command, the permissions of the kdb + * console and the lockdown state allow a command to be run. */ -static inline bool kdb_check_flags(kdb_cmdflags_t flags, int permissions, +static bool kdb_check_flags(kdb_cmdflags_t flags, int permissions, bool no_args) { /* permissions comes from userspace so needs massaging slightly */ @@ -1194,6 +1247,9 @@ static int kdb_local(kdb_reason_t reason, int error, struct pt_regs *regs, kdb_curr_task(raw_smp_processor_id()); KDB_DEBUG_STATE("kdb_local 1", reason); + + kdb_check_for_lockdown(); + kdb_go_count = 0; if (reason == KDB_REASON_DEBUG) { /* special case below */ diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index 762a928e18f92..8806444a68550 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -195,7 +195,7 @@ irqreturn_t handle_irq_event_percpu(struct irq_desc *desc) retval = __handle_irq_event_percpu(desc, &flags); - add_interrupt_randomness(desc->irq_data.irq, flags); + add_interrupt_randomness(desc->irq_data.irq); if (!noirqdebug) note_interrupt(desc, retval); diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index cc4dc2857a870..e12ce2821dba5 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -2378,6 +2379,20 @@ static int timekeeping_validate_timex(const struct __kernel_timex *txc) return 0; } +/** + * random_get_entropy_fallback - Returns the raw clock source value, + * used by random.c for platforms with no valid random_get_entropy(). + */ +unsigned long random_get_entropy_fallback(void) +{ + struct tk_read_base *tkr = &tk_core.timekeeper.tkr_mono; + struct clocksource *clock = READ_ONCE(tkr->clock); + + if (unlikely(timekeeping_suspended || !clock)) + return 0; + return clock->read(clock); +} +EXPORT_SYMBOL_GPL(random_get_entropy_fallback); /** * do_adjtimex() - Accessor function to NTP __do_adjtimex function diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 95f909540587c..3656fa8837834 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1426,8 +1426,7 @@ config WARN_ALL_UNSEEDED_RANDOM so architecture maintainers really need to do what they can to get the CRNG seeded sooner after the system is booted. However, since users cannot do anything actionable to - address this, by default the kernel will issue only a single - warning for the first use of unseeded randomness. + address this, by default this option is disabled. Say Y here if you want to receive warnings for all uses of unseeded randomness. This will be of use primarily for diff --git a/lib/crypto/Kconfig b/lib/crypto/Kconfig index 14c032de276e6..af3da5a8bde8d 100644 --- a/lib/crypto/Kconfig +++ b/lib/crypto/Kconfig @@ -1,7 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 -comment "Crypto library routines" - config CRYPTO_LIB_AES tristate @@ -9,14 +7,14 @@ config CRYPTO_LIB_ARC4 tristate config CRYPTO_ARCH_HAVE_LIB_BLAKE2S - tristate + bool help Declares whether the architecture provides an arch-specific accelerated implementation of the Blake2s library interface, either builtin or as a module. config CRYPTO_LIB_BLAKE2S_GENERIC - tristate + def_bool !CRYPTO_ARCH_HAVE_LIB_BLAKE2S help This symbol can be depended upon by arch implementations of the Blake2s library interface that require the generic code as a @@ -24,15 +22,6 @@ config CRYPTO_LIB_BLAKE2S_GENERIC implementation is enabled, this implementation serves the users of CRYPTO_LIB_BLAKE2S. -config CRYPTO_LIB_BLAKE2S - tristate "BLAKE2s hash function library" - depends on CRYPTO_ARCH_HAVE_LIB_BLAKE2S || !CRYPTO_ARCH_HAVE_LIB_BLAKE2S - select CRYPTO_LIB_BLAKE2S_GENERIC if CRYPTO_ARCH_HAVE_LIB_BLAKE2S=n - help - Enable the Blake2s library interface. This interface may be fulfilled - by either the generic implementation or an arch-specific one, if one - is available and enabled. - config CRYPTO_ARCH_HAVE_LIB_CHACHA tristate help @@ -51,7 +40,7 @@ config CRYPTO_LIB_CHACHA_GENERIC of CRYPTO_LIB_CHACHA. config CRYPTO_LIB_CHACHA - tristate "ChaCha library interface" + tristate depends on CRYPTO_ARCH_HAVE_LIB_CHACHA || !CRYPTO_ARCH_HAVE_LIB_CHACHA select CRYPTO_LIB_CHACHA_GENERIC if CRYPTO_ARCH_HAVE_LIB_CHACHA=n help @@ -76,7 +65,7 @@ config CRYPTO_LIB_CURVE25519_GENERIC of CRYPTO_LIB_CURVE25519. config CRYPTO_LIB_CURVE25519 - tristate "Curve25519 scalar multiplication library" + tristate depends on CRYPTO_ARCH_HAVE_LIB_CURVE25519 || !CRYPTO_ARCH_HAVE_LIB_CURVE25519 select CRYPTO_LIB_CURVE25519_GENERIC if CRYPTO_ARCH_HAVE_LIB_CURVE25519=n help @@ -111,7 +100,7 @@ config CRYPTO_LIB_POLY1305_GENERIC of CRYPTO_LIB_POLY1305. config CRYPTO_LIB_POLY1305 - tristate "Poly1305 library interface" + tristate depends on CRYPTO_ARCH_HAVE_LIB_POLY1305 || !CRYPTO_ARCH_HAVE_LIB_POLY1305 select CRYPTO_LIB_POLY1305_GENERIC if CRYPTO_ARCH_HAVE_LIB_POLY1305=n help @@ -120,7 +109,7 @@ config CRYPTO_LIB_POLY1305 is available and enabled. config CRYPTO_LIB_CHACHA20POLY1305 - tristate "ChaCha20-Poly1305 AEAD support (8-byte nonce library version)" + tristate depends on CRYPTO_ARCH_HAVE_LIB_CHACHA || !CRYPTO_ARCH_HAVE_LIB_CHACHA depends on CRYPTO_ARCH_HAVE_LIB_POLY1305 || !CRYPTO_ARCH_HAVE_LIB_POLY1305 select CRYPTO_LIB_CHACHA diff --git a/lib/crypto/Makefile b/lib/crypto/Makefile index 3a435629d9ce9..26be2bbe09c59 100644 --- a/lib/crypto/Makefile +++ b/lib/crypto/Makefile @@ -10,11 +10,10 @@ libaes-y := aes.o obj-$(CONFIG_CRYPTO_LIB_ARC4) += libarc4.o libarc4-y := arc4.o -obj-$(CONFIG_CRYPTO_LIB_BLAKE2S_GENERIC) += libblake2s-generic.o -libblake2s-generic-y += blake2s-generic.o - -obj-$(CONFIG_CRYPTO_LIB_BLAKE2S) += libblake2s.o -libblake2s-y += blake2s.o +# blake2s is used by the /dev/random driver which is always builtin +obj-y += libblake2s.o +libblake2s-y := blake2s.o +libblake2s-$(CONFIG_CRYPTO_LIB_BLAKE2S_GENERIC) += blake2s-generic.o obj-$(CONFIG_CRYPTO_LIB_CHACHA20POLY1305) += libchacha20poly1305.o libchacha20poly1305-y += chacha20poly1305.o diff --git a/lib/crypto/blake2s-generic.c b/lib/crypto/blake2s-generic.c index 04ff8df245136..75ccb3e633e65 100644 --- a/lib/crypto/blake2s-generic.c +++ b/lib/crypto/blake2s-generic.c @@ -37,7 +37,11 @@ static inline void blake2s_increment_counter(struct blake2s_state *state, state->t[1] += (state->t[0] < inc); } -void blake2s_compress_generic(struct blake2s_state *state,const u8 *block, +void blake2s_compress(struct blake2s_state *state, const u8 *block, + size_t nblocks, const u32 inc) + __weak __alias(blake2s_compress_generic); + +void blake2s_compress_generic(struct blake2s_state *state, const u8 *block, size_t nblocks, const u32 inc) { u32 m[16]; diff --git a/lib/crypto/blake2s-selftest.c b/lib/crypto/blake2s-selftest.c index 79ef404a990d2..409e4b7287704 100644 --- a/lib/crypto/blake2s-selftest.c +++ b/lib/crypto/blake2s-selftest.c @@ -3,7 +3,7 @@ * Copyright (C) 2015-2019 Jason A. Donenfeld . All Rights Reserved. */ -#include +#include #include /* @@ -15,7 +15,6 @@ * #include * * #include - * #include * * #define BLAKE2S_TESTVEC_COUNT 256 * @@ -58,16 +57,6 @@ * } * printf("};\n\n"); * - * printf("static const u8 blake2s_hmac_testvecs[][BLAKE2S_HASH_SIZE] __initconst = {\n"); - * - * HMAC(EVP_blake2s256(), key, sizeof(key), buf, sizeof(buf), hash, NULL); - * print_vec(hash, BLAKE2S_OUTBYTES); - * - * HMAC(EVP_blake2s256(), buf, sizeof(buf), key, sizeof(key), hash, NULL); - * print_vec(hash, BLAKE2S_OUTBYTES); - * - * printf("};\n"); - * * return 0; *} */ @@ -554,15 +543,6 @@ static const u8 blake2s_testvecs[][BLAKE2S_HASH_SIZE] __initconst = { 0xd6, 0x98, 0x6b, 0x07, 0x10, 0x65, 0x52, 0x65, }, }; -static const u8 blake2s_hmac_testvecs[][BLAKE2S_HASH_SIZE] __initconst = { - { 0xce, 0xe1, 0x57, 0x69, 0x82, 0xdc, 0xbf, 0x43, 0xad, 0x56, 0x4c, 0x70, - 0xed, 0x68, 0x16, 0x96, 0xcf, 0xa4, 0x73, 0xe8, 0xe8, 0xfc, 0x32, 0x79, - 0x08, 0x0a, 0x75, 0x82, 0xda, 0x3f, 0x05, 0x11, }, - { 0x77, 0x2f, 0x0c, 0x71, 0x41, 0xf4, 0x4b, 0x2b, 0xb3, 0xc6, 0xb6, 0xf9, - 0x60, 0xde, 0xe4, 0x52, 0x38, 0x66, 0xe8, 0xbf, 0x9b, 0x96, 0xc4, 0x9f, - 0x60, 0xd9, 0x24, 0x37, 0x99, 0xd6, 0xec, 0x31, }, -}; - bool __init blake2s_selftest(void) { u8 key[BLAKE2S_KEY_SIZE]; @@ -607,16 +587,5 @@ bool __init blake2s_selftest(void) } } - if (success) { - blake2s256_hmac(hash, buf, key, sizeof(buf), sizeof(key)); - success &= !memcmp(hash, blake2s_hmac_testvecs[0], BLAKE2S_HASH_SIZE); - - blake2s256_hmac(hash, key, buf, sizeof(key), sizeof(buf)); - success &= !memcmp(hash, blake2s_hmac_testvecs[1], BLAKE2S_HASH_SIZE); - - if (!success) - pr_err("blake2s256_hmac self-test: FAIL\n"); - } - return success; } diff --git a/lib/crypto/blake2s.c b/lib/crypto/blake2s.c index 41025a30c524c..80b194f9a0a09 100644 --- a/lib/crypto/blake2s.c +++ b/lib/crypto/blake2s.c @@ -15,98 +15,21 @@ #include #include #include -#include - -bool blake2s_selftest(void); void blake2s_update(struct blake2s_state *state, const u8 *in, size_t inlen) { - const size_t fill = BLAKE2S_BLOCK_SIZE - state->buflen; - - if (unlikely(!inlen)) - return; - if (inlen > fill) { - memcpy(state->buf + state->buflen, in, fill); - if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S)) - blake2s_compress_arch(state, state->buf, 1, - BLAKE2S_BLOCK_SIZE); - else - blake2s_compress_generic(state, state->buf, 1, - BLAKE2S_BLOCK_SIZE); - state->buflen = 0; - in += fill; - inlen -= fill; - } - if (inlen > BLAKE2S_BLOCK_SIZE) { - const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE); - /* Hash one less (full) block than strictly possible */ - if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S)) - blake2s_compress_arch(state, in, nblocks - 1, - BLAKE2S_BLOCK_SIZE); - else - blake2s_compress_generic(state, in, nblocks - 1, - BLAKE2S_BLOCK_SIZE); - in += BLAKE2S_BLOCK_SIZE * (nblocks - 1); - inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1); - } - memcpy(state->buf + state->buflen, in, inlen); - state->buflen += inlen; + __blake2s_update(state, in, inlen, false); } EXPORT_SYMBOL(blake2s_update); void blake2s_final(struct blake2s_state *state, u8 *out) { WARN_ON(IS_ENABLED(DEBUG) && !out); - blake2s_set_lastblock(state); - memset(state->buf + state->buflen, 0, - BLAKE2S_BLOCK_SIZE - state->buflen); /* Padding */ - if (IS_ENABLED(CONFIG_CRYPTO_ARCH_HAVE_LIB_BLAKE2S)) - blake2s_compress_arch(state, state->buf, 1, state->buflen); - else - blake2s_compress_generic(state, state->buf, 1, state->buflen); - cpu_to_le32_array(state->h, ARRAY_SIZE(state->h)); - memcpy(out, state->h, state->outlen); + __blake2s_final(state, out, false); memzero_explicit(state, sizeof(*state)); } EXPORT_SYMBOL(blake2s_final); -void blake2s256_hmac(u8 *out, const u8 *in, const u8 *key, const size_t inlen, - const size_t keylen) -{ - struct blake2s_state state; - u8 x_key[BLAKE2S_BLOCK_SIZE] __aligned(__alignof__(u32)) = { 0 }; - u8 i_hash[BLAKE2S_HASH_SIZE] __aligned(__alignof__(u32)); - int i; - - if (keylen > BLAKE2S_BLOCK_SIZE) { - blake2s_init(&state, BLAKE2S_HASH_SIZE); - blake2s_update(&state, key, keylen); - blake2s_final(&state, x_key); - } else - memcpy(x_key, key, keylen); - - for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i) - x_key[i] ^= 0x36; - - blake2s_init(&state, BLAKE2S_HASH_SIZE); - blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE); - blake2s_update(&state, in, inlen); - blake2s_final(&state, i_hash); - - for (i = 0; i < BLAKE2S_BLOCK_SIZE; ++i) - x_key[i] ^= 0x5c ^ 0x36; - - blake2s_init(&state, BLAKE2S_HASH_SIZE); - blake2s_update(&state, x_key, BLAKE2S_BLOCK_SIZE); - blake2s_update(&state, i_hash, BLAKE2S_HASH_SIZE); - blake2s_final(&state, i_hash); - - memcpy(out, i_hash, BLAKE2S_HASH_SIZE); - memzero_explicit(x_key, BLAKE2S_BLOCK_SIZE); - memzero_explicit(i_hash, BLAKE2S_HASH_SIZE); -} -EXPORT_SYMBOL(blake2s256_hmac); - static int __init mod_init(void) { if (!IS_ENABLED(CONFIG_CRYPTO_MANAGER_DISABLE_TESTS) && diff --git a/lib/random32.c b/lib/random32.c index 4d0e05e471d72..f0ab17c2244be 100644 --- a/lib/random32.c +++ b/lib/random32.c @@ -39,8 +39,9 @@ #include #include #include +#include +#include #include -#include /** * prandom_u32_state - seeded pseudo-random number generator. @@ -386,7 +387,6 @@ u32 prandom_u32(void) struct siprand_state *state = get_cpu_ptr(&net_rand_state); u32 res = siprand_u32(state); - trace_prandom_u32(res); put_cpu_ptr(&net_rand_state); return res; } @@ -552,9 +552,11 @@ static void prandom_reseed(struct timer_list *unused) * To avoid worrying about whether it's safe to delay that interrupt * long enough to seed all CPUs, just schedule an immediate timer event. */ -static void prandom_timer_start(struct random_ready_callback *unused) +static int prandom_timer_start(struct notifier_block *nb, + unsigned long action, void *data) { mod_timer(&seed_timer, jiffies); + return 0; } #ifdef CONFIG_RANDOM32_SELFTEST @@ -618,13 +620,13 @@ core_initcall(prandom32_state_selftest); */ static int __init prandom_init_late(void) { - static struct random_ready_callback random_ready = { - .func = prandom_timer_start + static struct notifier_block random_ready = { + .notifier_call = prandom_timer_start }; - int ret = add_random_ready_callback(&random_ready); + int ret = register_random_ready_notifier(&random_ready); if (ret == -EALREADY) { - prandom_timer_start(&random_ready); + prandom_timer_start(&random_ready, 0, NULL); ret = 0; } return ret; diff --git a/lib/sha1.c b/lib/sha1.c index 49257a915bb60..5ad4e49482728 100644 --- a/lib/sha1.c +++ b/lib/sha1.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include @@ -55,7 +56,8 @@ #define SHA_ROUND(t, input, fn, constant, A, B, C, D, E) do { \ __u32 TEMP = input(t); setW(t, TEMP); \ E += TEMP + rol32(A,5) + (fn) + (constant); \ - B = ror32(B, 2); } while (0) + B = ror32(B, 2); \ + TEMP = E; E = D; D = C; C = B; B = A; A = TEMP; } while (0) #define T_0_15(t, A, B, C, D, E) SHA_ROUND(t, SHA_SRC, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E ) #define T_16_19(t, A, B, C, D, E) SHA_ROUND(t, SHA_MIX, (((C^D)&B)^D) , 0x5a827999, A, B, C, D, E ) @@ -84,6 +86,7 @@ void sha1_transform(__u32 *digest, const char *data, __u32 *array) { __u32 A, B, C, D, E; + unsigned int i = 0; A = digest[0]; B = digest[1]; @@ -92,94 +95,24 @@ void sha1_transform(__u32 *digest, const char *data, __u32 *array) E = digest[4]; /* Round 1 - iterations 0-16 take their input from 'data' */ - T_0_15( 0, A, B, C, D, E); - T_0_15( 1, E, A, B, C, D); - T_0_15( 2, D, E, A, B, C); - T_0_15( 3, C, D, E, A, B); - T_0_15( 4, B, C, D, E, A); - T_0_15( 5, A, B, C, D, E); - T_0_15( 6, E, A, B, C, D); - T_0_15( 7, D, E, A, B, C); - T_0_15( 8, C, D, E, A, B); - T_0_15( 9, B, C, D, E, A); - T_0_15(10, A, B, C, D, E); - T_0_15(11, E, A, B, C, D); - T_0_15(12, D, E, A, B, C); - T_0_15(13, C, D, E, A, B); - T_0_15(14, B, C, D, E, A); - T_0_15(15, A, B, C, D, E); + for (; i < 16; ++i) + T_0_15(i, A, B, C, D, E); /* Round 1 - tail. Input from 512-bit mixing array */ - T_16_19(16, E, A, B, C, D); - T_16_19(17, D, E, A, B, C); - T_16_19(18, C, D, E, A, B); - T_16_19(19, B, C, D, E, A); + for (; i < 20; ++i) + T_16_19(i, A, B, C, D, E); /* Round 2 */ - T_20_39(20, A, B, C, D, E); - T_20_39(21, E, A, B, C, D); - T_20_39(22, D, E, A, B, C); - T_20_39(23, C, D, E, A, B); - T_20_39(24, B, C, D, E, A); - T_20_39(25, A, B, C, D, E); - T_20_39(26, E, A, B, C, D); - T_20_39(27, D, E, A, B, C); - T_20_39(28, C, D, E, A, B); - T_20_39(29, B, C, D, E, A); - T_20_39(30, A, B, C, D, E); - T_20_39(31, E, A, B, C, D); - T_20_39(32, D, E, A, B, C); - T_20_39(33, C, D, E, A, B); - T_20_39(34, B, C, D, E, A); - T_20_39(35, A, B, C, D, E); - T_20_39(36, E, A, B, C, D); - T_20_39(37, D, E, A, B, C); - T_20_39(38, C, D, E, A, B); - T_20_39(39, B, C, D, E, A); + for (; i < 40; ++i) + T_20_39(i, A, B, C, D, E); /* Round 3 */ - T_40_59(40, A, B, C, D, E); - T_40_59(41, E, A, B, C, D); - T_40_59(42, D, E, A, B, C); - T_40_59(43, C, D, E, A, B); - T_40_59(44, B, C, D, E, A); - T_40_59(45, A, B, C, D, E); - T_40_59(46, E, A, B, C, D); - T_40_59(47, D, E, A, B, C); - T_40_59(48, C, D, E, A, B); - T_40_59(49, B, C, D, E, A); - T_40_59(50, A, B, C, D, E); - T_40_59(51, E, A, B, C, D); - T_40_59(52, D, E, A, B, C); - T_40_59(53, C, D, E, A, B); - T_40_59(54, B, C, D, E, A); - T_40_59(55, A, B, C, D, E); - T_40_59(56, E, A, B, C, D); - T_40_59(57, D, E, A, B, C); - T_40_59(58, C, D, E, A, B); - T_40_59(59, B, C, D, E, A); + for (; i < 60; ++i) + T_40_59(i, A, B, C, D, E); /* Round 4 */ - T_60_79(60, A, B, C, D, E); - T_60_79(61, E, A, B, C, D); - T_60_79(62, D, E, A, B, C); - T_60_79(63, C, D, E, A, B); - T_60_79(64, B, C, D, E, A); - T_60_79(65, A, B, C, D, E); - T_60_79(66, E, A, B, C, D); - T_60_79(67, D, E, A, B, C); - T_60_79(68, C, D, E, A, B); - T_60_79(69, B, C, D, E, A); - T_60_79(70, A, B, C, D, E); - T_60_79(71, E, A, B, C, D); - T_60_79(72, D, E, A, B, C); - T_60_79(73, C, D, E, A, B); - T_60_79(74, B, C, D, E, A); - T_60_79(75, A, B, C, D, E); - T_60_79(76, E, A, B, C, D); - T_60_79(77, D, E, A, B, C); - T_60_79(78, C, D, E, A, B); - T_60_79(79, B, C, D, E, A); + for (; i < 80; ++i) + T_60_79(i, A, B, C, D, E); digest[0] += A; digest[1] += B; diff --git a/lib/siphash.c b/lib/siphash.c index 025f0cbf6d7a7..b4055b1cc2f67 100644 --- a/lib/siphash.c +++ b/lib/siphash.c @@ -18,19 +18,13 @@ #include #endif -#define SIPROUND \ - do { \ - v0 += v1; v1 = rol64(v1, 13); v1 ^= v0; v0 = rol64(v0, 32); \ - v2 += v3; v3 = rol64(v3, 16); v3 ^= v2; \ - v0 += v3; v3 = rol64(v3, 21); v3 ^= v0; \ - v2 += v1; v1 = rol64(v1, 17); v1 ^= v2; v2 = rol64(v2, 32); \ - } while (0) +#define SIPROUND SIPHASH_PERMUTATION(v0, v1, v2, v3) #define PREAMBLE(len) \ - u64 v0 = 0x736f6d6570736575ULL; \ - u64 v1 = 0x646f72616e646f6dULL; \ - u64 v2 = 0x6c7967656e657261ULL; \ - u64 v3 = 0x7465646279746573ULL; \ + u64 v0 = SIPHASH_CONST_0; \ + u64 v1 = SIPHASH_CONST_1; \ + u64 v2 = SIPHASH_CONST_2; \ + u64 v3 = SIPHASH_CONST_3; \ u64 b = ((u64)(len)) << 56; \ v3 ^= key->key[1]; \ v2 ^= key->key[0]; \ @@ -389,19 +383,13 @@ u32 hsiphash_4u32(const u32 first, const u32 second, const u32 third, } EXPORT_SYMBOL(hsiphash_4u32); #else -#define HSIPROUND \ - do { \ - v0 += v1; v1 = rol32(v1, 5); v1 ^= v0; v0 = rol32(v0, 16); \ - v2 += v3; v3 = rol32(v3, 8); v3 ^= v2; \ - v0 += v3; v3 = rol32(v3, 7); v3 ^= v0; \ - v2 += v1; v1 = rol32(v1, 13); v1 ^= v2; v2 = rol32(v2, 16); \ - } while (0) +#define HSIPROUND HSIPHASH_PERMUTATION(v0, v1, v2, v3) #define HPREAMBLE(len) \ - u32 v0 = 0; \ - u32 v1 = 0; \ - u32 v2 = 0x6c796765U; \ - u32 v3 = 0x74656462U; \ + u32 v0 = HSIPHASH_CONST_0; \ + u32 v1 = HSIPHASH_CONST_1; \ + u32 v2 = HSIPHASH_CONST_2; \ + u32 v3 = HSIPHASH_CONST_3; \ u32 b = ((u32)(len)) << 24; \ v3 ^= key->key[1]; \ v2 ^= key->key[0]; \ diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 8ade1a86d8187..daf32a489dc06 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -756,14 +756,16 @@ static void enable_ptr_key_workfn(struct work_struct *work) static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn); -static void fill_random_ptr_key(struct random_ready_callback *unused) +static int fill_random_ptr_key(struct notifier_block *nb, + unsigned long action, void *data) { /* This may be in an interrupt handler. */ queue_work(system_unbound_wq, &enable_ptr_key_work); + return 0; } -static struct random_ready_callback random_ready = { - .func = fill_random_ptr_key +static struct notifier_block random_ready = { + .notifier_call = fill_random_ptr_key }; static int __init initialize_ptr_random(void) @@ -777,7 +779,7 @@ static int __init initialize_ptr_random(void) return 0; } - ret = add_random_ready_callback(&random_ready); + ret = register_random_ready_notifier(&random_ready); if (!ret) { return 0; } else if (ret == -EALREADY) { diff --git a/mm/util.c b/mm/util.c index 8904727607907..ba9643de689ea 100644 --- a/mm/util.c +++ b/mm/util.c @@ -331,6 +331,38 @@ unsigned long randomize_stack_top(unsigned long stack_top) #endif } +/** + * randomize_page - Generate a random, page aligned address + * @start: The smallest acceptable address the caller will take. + * @range: The size of the area, starting at @start, within which the + * random address must fall. + * + * If @start + @range would overflow, @range is capped. + * + * NOTE: Historical use of randomize_range, which this replaces, presumed that + * @start was already page aligned. We now align it regardless. + * + * Return: A page aligned address within [start, start + range). On error, + * @start is returned. + */ +unsigned long randomize_page(unsigned long start, unsigned long range) +{ + if (!PAGE_ALIGNED(start)) { + range -= PAGE_ALIGN(start) - start; + start = PAGE_ALIGN(start); + } + + if (start > ULONG_MAX - range) + range = ULONG_MAX - start; + + range >>= PAGE_SHIFT; + + if (range == 0) + return start; + + return start + (get_random_long() % range << PAGE_SHIFT); +} + #ifdef CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT unsigned long arch_randomize_brk(struct mm_struct *mm) { diff --git a/net/core/secure_seq.c b/net/core/secure_seq.c index b8a33c841846f..7131cd1fb2ad5 100644 --- a/net/core/secure_seq.c +++ b/net/core/secure_seq.c @@ -96,7 +96,7 @@ u32 secure_tcpv6_seq(const __be32 *saddr, const __be32 *daddr, } EXPORT_SYMBOL(secure_tcpv6_seq); -u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, +u64 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr, __be16 dport) { const struct { @@ -146,7 +146,7 @@ u32 secure_tcp_seq(__be32 saddr, __be32 daddr, } EXPORT_SYMBOL_GPL(secure_tcp_seq); -u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport) +u64 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport) { net_secret_init(); return siphash_4u32((__force u32)saddr, (__force u32)daddr, diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c index 915b8e1bd9efb..44b524136f953 100644 --- a/net/ipv4/inet_hashtables.c +++ b/net/ipv4/inet_hashtables.c @@ -504,7 +504,7 @@ not_unique: return -EADDRNOTAVAIL; } -static u32 inet_sk_port_offset(const struct sock *sk) +static u64 inet_sk_port_offset(const struct sock *sk) { const struct inet_sock *inet = inet_sk(sk); @@ -722,8 +722,19 @@ void inet_unhash(struct sock *sk) } EXPORT_SYMBOL_GPL(inet_unhash); +/* RFC 6056 3.3.4. Algorithm 4: Double-Hash Port Selection Algorithm + * Note that we use 32bit integers (vs RFC 'short integers') + * because 2^16 is not a multiple of num_ephemeral and this + * property might be used by clever attacker. + * RFC claims using TABLE_LENGTH=10 buckets gives an improvement, + * we use 256 instead to really give more isolation and + * privacy, this only consumes 1 KB of kernel memory. + */ +#define INET_TABLE_PERTURB_SHIFT 8 +static u32 table_perturb[1 << INET_TABLE_PERTURB_SHIFT]; + int __inet_hash_connect(struct inet_timewait_death_row *death_row, - struct sock *sk, u32 port_offset, + struct sock *sk, u64 port_offset, int (*check_established)(struct inet_timewait_death_row *, struct sock *, __u16, struct inet_timewait_sock **)) { @@ -735,8 +746,8 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, struct inet_bind_bucket *tb; u32 remaining, offset; int ret, i, low, high; - static u32 hint; int l3mdev; + u32 index; if (port) { head = &hinfo->bhash[inet_bhashfn(net, port, @@ -763,7 +774,12 @@ int __inet_hash_connect(struct inet_timewait_death_row *death_row, if (likely(remaining > 1)) remaining &= ~1U; - offset = (hint + port_offset) % remaining; + net_get_random_once(table_perturb, sizeof(table_perturb)); + index = hash_32(port_offset, INET_TABLE_PERTURB_SHIFT); + + offset = READ_ONCE(table_perturb[index]) + port_offset; + offset %= remaining; + /* In first pass we try ports of @low parity. * inet_csk_get_port() does the opposite choice. */ @@ -817,7 +833,7 @@ next_port: return -EADDRNOTAVAIL; ok: - hint += i + 2; + WRITE_ONCE(table_perturb[index], READ_ONCE(table_perturb[index]) + i + 2); /* Head lock still held and bh's disabled */ inet_bind_hash(sk, tb, port); @@ -840,7 +856,7 @@ ok: int inet_hash_connect(struct inet_timewait_death_row *death_row, struct sock *sk) { - u32 port_offset = 0; + u64 port_offset = 0; if (!inet_sk(sk)->inet_num) port_offset = inet_sk_port_offset(sk); diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c index 0a2e7f2283911..40203255ed88b 100644 --- a/net/ipv6/inet6_hashtables.c +++ b/net/ipv6/inet6_hashtables.c @@ -308,7 +308,7 @@ not_unique: return -EADDRNOTAVAIL; } -static u32 inet6_sk_port_offset(const struct sock *sk) +static u64 inet6_sk_port_offset(const struct sock *sk) { const struct inet_sock *inet = inet_sk(sk); @@ -320,7 +320,7 @@ static u32 inet6_sk_port_offset(const struct sock *sk) int inet6_hash_connect(struct inet_timewait_death_row *death_row, struct sock *sk) { - u32 port_offset = 0; + u64 port_offset = 0; if (!inet_sk(sk)->inet_num) port_offset = inet6_sk_port_offset(sk); diff --git a/security/security.c b/security/security.c index d9d42d64f89f2..360706cdababc 100644 --- a/security/security.c +++ b/security/security.c @@ -59,10 +59,12 @@ const char *const lockdown_reasons[LOCKDOWN_CONFIDENTIALITY_MAX+1] = { [LOCKDOWN_DEBUGFS] = "debugfs access", [LOCKDOWN_XMON_WR] = "xmon write access", [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", + [LOCKDOWN_DBG_WRITE_KERNEL] = "use of kgdb/kdb to write kernel RAM", [LOCKDOWN_INTEGRITY_MAX] = "integrity", [LOCKDOWN_KCORE] = "/proc/kcore access", [LOCKDOWN_KPROBES] = "use of kprobes", [LOCKDOWN_BPF_READ] = "use of bpf to read kernel RAM", + [LOCKDOWN_DBG_READ_KERNEL] = "use of kgdb/kdb to read kernel RAM", [LOCKDOWN_PERF] = "unsafe use of perf", [LOCKDOWN_TRACEFS] = "use of tracefs", [LOCKDOWN_XMON_RW] = "xmon read and write access", diff --git a/sound/pci/ctxfi/ctatc.c b/sound/pci/ctxfi/ctatc.c index f8ac96cf38a43..06775519dab00 100644 --- a/sound/pci/ctxfi/ctatc.c +++ b/sound/pci/ctxfi/ctatc.c @@ -36,6 +36,7 @@ | ((IEC958_AES3_CON_FS_48000) << 24)) static const struct snd_pci_quirk subsys_20k1_list[] = { + SND_PCI_QUIRK(PCI_VENDOR_ID_CREATIVE, 0x0021, "SB046x", CTSB046X), SND_PCI_QUIRK(PCI_VENDOR_ID_CREATIVE, 0x0022, "SB055x", CTSB055X), SND_PCI_QUIRK(PCI_VENDOR_ID_CREATIVE, 0x002f, "SB055x", CTSB055X), SND_PCI_QUIRK(PCI_VENDOR_ID_CREATIVE, 0x0029, "SB073x", CTSB073X), @@ -64,6 +65,7 @@ static const struct snd_pci_quirk subsys_20k2_list[] = { static const char *ct_subsys_name[NUM_CTCARDS] = { /* 20k1 models */ + [CTSB046X] = "SB046x", [CTSB055X] = "SB055x", [CTSB073X] = "SB073x", [CTUAA] = "UAA", diff --git a/sound/pci/ctxfi/cthardware.h b/sound/pci/ctxfi/cthardware.h index 9e6b83bd432d9..b50d61a08e283 100644 --- a/sound/pci/ctxfi/cthardware.h +++ b/sound/pci/ctxfi/cthardware.h @@ -26,8 +26,9 @@ enum CHIPTYP { enum CTCARDS { /* 20k1 models */ + CTSB046X, + CT20K1_MODEL_FIRST = CTSB046X, CTSB055X, - CT20K1_MODEL_FIRST = CTSB055X, CTSB073X, CTUAA, CT20K1_UNKNOWN,