X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=crypto%2Fbn%2Fbn_rand.c;h=2b3e6f2076e88a7871b8735553e770bdc8cce686;hp=9c0a4eef06fedc22a3ebb7ee8ccb1c38e6f37863;hb=31ca19403d56ad71d823cf62990518dfc6905bb4;hpb=e0a675e211302257256ed80ea1edeff329c9b9e9 diff --git a/crypto/bn/bn_rand.c b/crypto/bn/bn_rand.c index 9c0a4eef06..2b3e6f2076 100644 --- a/crypto/bn/bn_rand.c +++ b/crypto/bn/bn_rand.c @@ -1,7 +1,7 @@ /* - * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved. * - * Licensed under the OpenSSL license (the "License"). You may not use + * Licensed under the Apache License 2.0 (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html @@ -10,25 +10,31 @@ #include #include #include "internal/cryptlib.h" +#include "internal/rand_int.h" #include "bn_lcl.h" #include #include +#include -static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom) +typedef enum bnrand_flag_e { + NORMAL, TESTING, PRIVATE +} BNRAND_FLAG; + +static int bnrand(BNRAND_FLAG flag, BIGNUM *rnd, int bits, int top, int bottom, + BN_CTX *ctx) { unsigned char *buf = NULL; - int ret = 0, bit, bytes, mask; - time_t tim; - - if (bits < 0 || (bits == 1 && top > 0)) { - BNerr(BN_F_BNRAND, BN_R_BITS_TOO_SMALL); - return 0; - } + int b, ret = 0, bit, bytes, mask; + OPENSSL_CTX *libctx = bn_get_lib_ctx(ctx); if (bits == 0) { + if (top != BN_RAND_TOP_ANY || bottom != BN_RAND_BOTTOM_ANY) + goto toosmall; BN_zero(rnd); return 1; } + if (bits < 0 || (bits == 1 && top > 0)) + goto toosmall; bytes = (bits + 7) / 8; bit = (bits - 1) % 8; @@ -41,13 +47,12 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom) } /* make a random number and set the top and bottom bits */ - time(&tim); - RAND_add(&tim, sizeof(tim), 0.0); - - if (RAND_bytes(buf, bytes) <= 0) + b = flag == NORMAL ? rand_bytes_ex(libctx, buf, bytes) + : rand_priv_bytes_ex(libctx, buf, bytes); + if (b <= 0) goto err; - if (pseudorand == 2) { + if (flag == TESTING) { /* * generate patterns that are more likely to trigger BN library bugs */ @@ -55,7 +60,7 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom) unsigned char c; for (i = 0; i < bytes; i++) { - if (RAND_bytes(&c, 1) <= 0) + if (rand_bytes_ex(libctx, &c, 1) <= 0) goto err; if (c >= 128 && i > 0) buf[i] = buf[i - 1]; @@ -87,34 +92,50 @@ static int bnrand(int pseudorand, BIGNUM *rnd, int bits, int top, int bottom) err: OPENSSL_clear_free(buf, bytes); bn_check_top(rnd); - return (ret); + return ret; + +toosmall: + BNerr(BN_F_BNRAND, BN_R_BITS_TOO_SMALL); + return 0; } +int BN_rand_ex(BIGNUM *rnd, int bits, int top, int bottom, BN_CTX *ctx) +{ + return bnrand(NORMAL, rnd, bits, top, bottom, ctx); +} +#ifndef FIPS_MODE int BN_rand(BIGNUM *rnd, int bits, int top, int bottom) { - return bnrand(0, rnd, bits, top, bottom); + return bnrand(NORMAL, rnd, bits, top, bottom, NULL); } -int BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom) +int BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom) { - return bnrand(1, rnd, bits, top, bottom); + return bnrand(TESTING, rnd, bits, top, bottom, NULL); } +#endif -int BN_bntest_rand(BIGNUM *rnd, int bits, int top, int bottom) +int BN_priv_rand_ex(BIGNUM *rnd, int bits, int top, int bottom, BN_CTX *ctx) { - return bnrand(2, rnd, bits, top, bottom); + return bnrand(PRIVATE, rnd, bits, top, bottom, ctx); } +#ifndef FIPS_MODE +int BN_priv_rand(BIGNUM *rnd, int bits, int top, int bottom) +{ + return bnrand(PRIVATE, rnd, bits, top, bottom, NULL); +} +#endif + /* random number r: 0 <= r < range */ -static int bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range) +static int bnrand_range(BNRAND_FLAG flag, BIGNUM *r, const BIGNUM *range, + BN_CTX *ctx) { - int (*bn_rand) (BIGNUM *, int, int, int) = - pseudo ? BN_pseudo_rand : BN_rand; int n; int count = 100; if (range->neg || BN_is_zero(range)) { - BNerr(BN_F_BN_RAND_RANGE, BN_R_INVALID_RANGE); + BNerr(BN_F_BNRAND_RANGE, BN_R_INVALID_RANGE); return 0; } @@ -130,8 +151,10 @@ static int bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range) * than range */ do { - if (!bn_rand(r, n + 1, -1, 0)) + if (!bnrand(flag, r, n + 1, BN_RAND_TOP_ANY, BN_RAND_BOTTOM_ANY, + ctx)) return 0; + /* * If r < 3*range, use r := r MOD range (which is either r, r - * range, or r - 2*range). Otherwise, iterate once more. Since @@ -147,7 +170,7 @@ static int bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range) } if (!--count) { - BNerr(BN_F_BN_RAND_RANGE, BN_R_TOO_MANY_ITERATIONS); + BNerr(BN_F_BNRAND_RANGE, BN_R_TOO_MANY_ITERATIONS); return 0; } @@ -156,11 +179,11 @@ static int bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range) } else { do { /* range = 11..._2 or range = 101..._2 */ - if (!bn_rand(r, n, -1, 0)) + if (!bnrand(flag, r, n, BN_RAND_TOP_ANY, BN_RAND_BOTTOM_ANY, ctx)) return 0; if (!--count) { - BNerr(BN_F_BN_RAND_RANGE, BN_R_TOO_MANY_ITERATIONS); + BNerr(BN_F_BNRAND_RANGE, BN_R_TOO_MANY_ITERATIONS); return 0; } } @@ -171,15 +194,39 @@ static int bn_rand_range(int pseudo, BIGNUM *r, const BIGNUM *range) return 1; } +int BN_rand_range_ex(BIGNUM *r, const BIGNUM *range, BN_CTX *ctx) +{ + return bnrand_range(NORMAL, r, range, ctx); +} + +#ifndef FIPS_MODE int BN_rand_range(BIGNUM *r, const BIGNUM *range) { - return bn_rand_range(0, r, range); + return bnrand_range(NORMAL, r, range, NULL); +} +#endif + +int BN_priv_rand_range_ex(BIGNUM *r, const BIGNUM *range, BN_CTX *ctx) +{ + return bnrand_range(PRIVATE, r, range, ctx); +} + +#ifndef FIPS_MODE +int BN_priv_rand_range(BIGNUM *r, const BIGNUM *range) +{ + return bnrand_range(PRIVATE, r, range, NULL); +} + +int BN_pseudo_rand(BIGNUM *rnd, int bits, int top, int bottom) +{ + return BN_rand(rnd, bits, top, bottom); } int BN_pseudo_rand_range(BIGNUM *r, const BIGNUM *range) { - return bn_rand_range(1, r, range); + return BN_rand_range(r, range); } +#endif /* * BN_generate_dsa_nonce generates a random number 0 <= out < range. Unlike @@ -193,7 +240,7 @@ int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, const BIGNUM *priv, const unsigned char *message, size_t message_len, BN_CTX *ctx) { - SHA512_CTX sha; + EVP_MD_CTX *mdctx = EVP_MD_CTX_new(); /* * We use 512 bits of random data per iteration to ensure that we have at * least |range| bits of randomness. @@ -204,16 +251,20 @@ int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, /* We generate |range|+8 bytes of random output. */ const unsigned num_k_bytes = BN_num_bytes(range) + 8; unsigned char private_bytes[96]; - unsigned char *k_bytes; + unsigned char *k_bytes = NULL; int ret = 0; + EVP_MD *md = NULL; + OPENSSL_CTX *libctx = bn_get_lib_ctx(ctx); + + if (mdctx == NULL) + goto err; k_bytes = OPENSSL_malloc(num_k_bytes); if (k_bytes == NULL) goto err; /* We copy |priv| into a local buffer to avoid exposing its length. */ - todo = sizeof(priv->d[0]) * priv->top; - if (todo > sizeof(private_bytes)) { + if (BN_bn2binpad(priv, private_bytes, sizeof(private_bytes)) < 0) { /* * No reasonable DSA or ECDSA key should have a private key this * large and we don't handle this case in order to avoid leaking the @@ -222,18 +273,24 @@ int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, BNerr(BN_F_BN_GENERATE_DSA_NONCE, BN_R_PRIVATE_KEY_TOO_LARGE); goto err; } - memcpy(private_bytes, priv->d, todo); - memset(private_bytes + todo, 0, sizeof(private_bytes) - todo); + md = EVP_MD_fetch(libctx, "SHA512", NULL); + if (md == NULL) { + BNerr(BN_F_BN_GENERATE_DSA_NONCE, BN_R_NO_SUITABLE_DIGEST); + goto err; + } for (done = 0; done < num_k_bytes;) { - if (RAND_bytes(random_bytes, sizeof(random_bytes)) != 1) + if (!rand_priv_bytes_ex(libctx, random_bytes, sizeof(random_bytes))) + goto err; + + if (!EVP_DigestInit_ex(mdctx, md, NULL) + || !EVP_DigestUpdate(mdctx, &done, sizeof(done)) + || !EVP_DigestUpdate(mdctx, private_bytes, + sizeof(private_bytes)) + || !EVP_DigestUpdate(mdctx, message, message_len) + || !EVP_DigestUpdate(mdctx, random_bytes, sizeof(random_bytes)) + || !EVP_DigestFinal_ex(mdctx, digest, NULL)) goto err; - SHA512_Init(&sha); - SHA512_Update(&sha, &done, sizeof(done)); - SHA512_Update(&sha, private_bytes, sizeof(private_bytes)); - SHA512_Update(&sha, message, message_len); - SHA512_Update(&sha, random_bytes, sizeof(random_bytes)); - SHA512_Final(digest, &sha); todo = num_k_bytes - done; if (todo > SHA512_DIGEST_LENGTH) @@ -249,6 +306,9 @@ int BN_generate_dsa_nonce(BIGNUM *out, const BIGNUM *range, ret = 1; err: + EVP_MD_CTX_free(mdctx); + EVP_MD_free(md); OPENSSL_free(k_bytes); + OPENSSL_cleanse(private_bytes, sizeof(private_bytes)); return ret; }