diff options
Diffstat (limited to 'src/lib/crypt_ops/crypto_rand.c')
| -rw-r--r-- | src/lib/crypt_ops/crypto_rand.c | 133 |
1 files changed, 17 insertions, 116 deletions
diff --git a/src/lib/crypt_ops/crypto_rand.c b/src/lib/crypt_ops/crypto_rand.c index 206929d6b3..ce6f21dbb4 100644 --- a/src/lib/crypt_ops/crypto_rand.c +++ b/src/lib/crypt_ops/crypto_rand.c @@ -1,7 +1,7 @@ /* Copyright (c) 2001, Matej Pfajfar. * Copyright (c) 2001-2004, Roger Dingledine. * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson. - * Copyright (c) 2007-2019, The Tor Project, Inc. */ + * Copyright (c) 2007-2020, The Tor Project, Inc. */ /* See LICENSE for licensing information */ /** @@ -11,7 +11,6 @@ * number generators, and working with randomness. **/ -#ifndef CRYPTO_RAND_PRIVATE #define CRYPTO_RAND_PRIVATE #include "lib/crypt_ops/crypto_rand.h" @@ -37,17 +36,18 @@ #include "lib/defs/digest_sizes.h" #include "lib/crypt_ops/crypto_digest.h" +#include "lib/ctime/di_ops.h" #ifdef ENABLE_NSS #include "lib/crypt_ops/crypto_nss_mgt.h" #endif #ifdef ENABLE_OPENSSL -DISABLE_GCC_WARNING(redundant-decls) +DISABLE_GCC_WARNING("-Wredundant-decls") #include <openssl/rand.h> #include <openssl/sha.h> -ENABLE_GCC_WARNING(redundant-decls) -#endif +ENABLE_GCC_WARNING("-Wredundant-decls") +#endif /* defined(ENABLE_OPENSSL) */ #ifdef ENABLE_NSS #include <pk11pub.h> @@ -248,7 +248,7 @@ crypto_strongest_rand_fallback(uint8_t *out, size_t out_len) (void)out; (void)out_len; return -1; -#else /* !(defined(_WIN32)) */ +#else /* !defined(_WIN32) */ static const char *filenames[] = { "/dev/srandom", "/dev/urandom", "/dev/random", NULL }; @@ -315,7 +315,7 @@ crypto_strongest_rand_raw(uint8_t *out, size_t out_len) } } - if ((out_len < sanity_min_size) || !tor_mem_is_zero((char*)out, out_len)) + if ((out_len < sanity_min_size) || !safe_mem_is_zero((char*)out, out_len)) return 0; } @@ -419,7 +419,7 @@ crypto_seed_openssl_rng(void) else return -1; } -#endif +#endif /* defined(ENABLE_OPENSSL) */ #ifdef ENABLE_NSS /** @@ -442,7 +442,7 @@ crypto_seed_nss_rng(void) return load_entropy_ok ? 0 : -1; } -#endif +#endif /* defined(ENABLE_NSS) */ /** * Seed the RNG for any and all crypto libraries that we're using with bytes @@ -520,7 +520,7 @@ crypto_rand_unmocked(char *to, size_t n) #undef BUFLEN } -#else +#else /* !defined(ENABLE_NSS) */ int r = RAND_bytes((unsigned char*)to, (int)n); /* We consider a PRNG failure non-survivable. Let's assert so that we get a * stack trace about where it happened. @@ -530,111 +530,14 @@ crypto_rand_unmocked(char *to, size_t n) } /** - * Return a pseudorandom integer, chosen uniformly from the values - * between 0 and <b>max</b>-1 inclusive. <b>max</b> must be between 1 and - * INT_MAX+1, inclusive. + * Draw an unsigned 32-bit integer uniformly at random. */ -int -crypto_rand_int(unsigned int max) -{ - unsigned int val; - unsigned int cutoff; - tor_assert(max <= ((unsigned int)INT_MAX)+1); - tor_assert(max > 0); /* don't div by 0 */ - - /* We ignore any values that are >= 'cutoff,' to avoid biasing the - * distribution with clipping at the upper end of unsigned int's - * range. - */ - cutoff = UINT_MAX - (UINT_MAX%max); - while (1) { - crypto_rand((char*)&val, sizeof(val)); - if (val < cutoff) - return val % max; - } -} - -/** - * Return a pseudorandom integer, chosen uniformly from the values i such - * that min <= i < max. - * - * <b>min</b> MUST be in range [0, <b>max</b>). - * <b>max</b> MUST be in range (min, INT_MAX]. - **/ -int -crypto_rand_int_range(unsigned int min, unsigned int max) -{ - tor_assert(min < max); - tor_assert(max <= INT_MAX); - - /* The overflow is avoided here because crypto_rand_int() returns a value - * between 0 and (max - min) inclusive. */ - return min + crypto_rand_int(max - min); -} - -/** - * As crypto_rand_int_range, but supports uint64_t. - **/ -uint64_t -crypto_rand_uint64_range(uint64_t min, uint64_t max) +uint32_t +crypto_rand_u32(void) { - tor_assert(min < max); - return min + crypto_rand_uint64(max - min); -} - -/** - * As crypto_rand_int_range, but supports time_t. - **/ -time_t -crypto_rand_time_range(time_t min, time_t max) -{ - tor_assert(min < max); - return min + (time_t)crypto_rand_uint64(max - min); -} - -/** - * Return a pseudorandom 64-bit integer, chosen uniformly from the values - * between 0 and <b>max</b>-1 inclusive. - **/ -uint64_t -crypto_rand_uint64(uint64_t max) -{ - uint64_t val; - uint64_t cutoff; - tor_assert(max < UINT64_MAX); - tor_assert(max > 0); /* don't div by 0 */ - - /* We ignore any values that are >= 'cutoff,' to avoid biasing the - * distribution with clipping at the upper end of unsigned int's - * range. - */ - cutoff = UINT64_MAX - (UINT64_MAX%max); - while (1) { - crypto_rand((char*)&val, sizeof(val)); - if (val < cutoff) - return val % max; - } -} - -/** - * Return a pseudorandom double d, chosen uniformly from the range - * 0.0 <= d < 1.0. - **/ -double -crypto_rand_double(void) -{ - /* We just use an unsigned int here; we don't really care about getting - * more than 32 bits of resolution */ - unsigned int u; - crypto_rand((char*)&u, sizeof(u)); -#if SIZEOF_INT == 4 -#define UINT_MAX_AS_DOUBLE 4294967296.0 -#elif SIZEOF_INT == 8 -#define UINT_MAX_AS_DOUBLE 1.8446744073709552e+19 -#else -#error SIZEOF_INT is neither 4 nor 8 -#endif /* SIZEOF_INT == 4 || ... */ - return ((double)u) / UINT_MAX_AS_DOUBLE; + uint32_t rand; + crypto_rand((void*)&rand, sizeof(rand)); + return rand; } /** @@ -724,8 +627,6 @@ crypto_force_rand_ssleay(void) RAND_set_rand_method(default_method); return 1; } -#endif +#endif /* defined(ENABLE_OPENSSL) */ return 0; } - -#endif /* !defined(CRYPTO_RAND_PRIVATE) */ |