diff options
Diffstat (limited to 'deps/openssl/openssl/crypto/ec/ecdsa_ossl.c')
| -rw-r--r-- | deps/openssl/openssl/crypto/ec/ecdsa_ossl.c | 132 |
1 files changed, 38 insertions, 94 deletions
diff --git a/deps/openssl/openssl/crypto/ec/ecdsa_ossl.c b/deps/openssl/openssl/crypto/ec/ecdsa_ossl.c index 449be0e92a..9e4a68d9ca 100644 --- a/deps/openssl/openssl/crypto/ec/ecdsa_ossl.c +++ b/deps/openssl/openssl/crypto/ec/ecdsa_ossl.c @@ -1,5 +1,5 @@ /* - * Copyright 2002-2017 The OpenSSL Project Authors. All Rights Reserved. + * Copyright 2002-2018 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the OpenSSL license (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy @@ -10,9 +10,8 @@ #include <string.h> #include <openssl/err.h> #include <openssl/obj_mac.h> -#include <openssl/bn.h> #include <openssl/rand.h> -#include <openssl/ec.h> +#include "internal/bn_int.h" #include "ec_lcl.h" int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen, @@ -53,13 +52,12 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, return 0; } - if (ctx_in == NULL) { + if ((ctx = ctx_in) == NULL) { if ((ctx = BN_CTX_new()) == NULL) { ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE); return 0; } - } else - ctx = ctx_in; + } k = BN_new(); /* this value is later returned in *kinvp */ r = BN_new(); /* this value is later returned in *rp */ @@ -73,10 +71,6 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, goto err; } order = EC_GROUP_get0_order(group); - if (order == NULL) { - ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); - goto err; - } /* Preallocate space */ order_bits = BN_num_bits(order); @@ -87,23 +81,23 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, do { /* get random k */ - do + do { if (dgst != NULL) { - if (!BN_generate_dsa_nonce - (k, order, EC_KEY_get0_private_key(eckey), dgst, dlen, - ctx)) { + if (!BN_generate_dsa_nonce(k, order, + EC_KEY_get0_private_key(eckey), + dgst, dlen, ctx)) { ECerr(EC_F_ECDSA_SIGN_SETUP, - EC_R_RANDOM_NUMBER_GENERATION_FAILED); + EC_R_RANDOM_NUMBER_GENERATION_FAILED); goto err; } } else { if (!BN_rand_range(k, order)) { ECerr(EC_F_ECDSA_SIGN_SETUP, - EC_R_RANDOM_NUMBER_GENERATION_FAILED); + EC_R_RANDOM_NUMBER_GENERATION_FAILED); goto err; } } - while (BN_is_zero(k)); + } while (BN_is_zero(k)); /* * We do not want timing information to leak the length of k, so we @@ -129,18 +123,16 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, } if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == NID_X9_62_prime_field) { - if (!EC_POINT_get_affine_coordinates_GFp - (group, tmp_point, X, NULL, ctx)) { + if (!EC_POINT_get_affine_coordinates_GFp(group, tmp_point, X, + NULL, ctx)) { ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); goto err; } } #ifndef OPENSSL_NO_EC2M else { /* NID_X9_62_characteristic_two_field */ - - if (!EC_POINT_get_affine_coordinates_GF2m(group, - tmp_point, X, NULL, - ctx)) { + if (!EC_POINT_get_affine_coordinates_GF2m(group, tmp_point, X, + NULL, ctx)) { ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); goto err; } @@ -150,8 +142,7 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, ECerr(EC_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); goto err; } - } - while (BN_is_zero(r)); + } while (BN_is_zero(r)); /* compute the inverse of k */ if (EC_GROUP_get_mont_data(group) != NULL) { @@ -210,8 +201,7 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len, EC_KEY *eckey) { int ok = 0, i; - BIGNUM *kinv = NULL, *s, *m = NULL, *tmp = NULL, *blind = NULL; - BIGNUM *blindm = NULL; + BIGNUM *kinv = NULL, *s, *m = NULL; const BIGNUM *order, *ckinv; BN_CTX *ctx = NULL; const EC_GROUP *group; @@ -244,27 +234,13 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len, } s = ret->s; - ctx = BN_CTX_secure_new(); - if (ctx == NULL) { - ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE); - goto err; - } - - BN_CTX_start(ctx); - tmp = BN_CTX_get(ctx); - m = BN_CTX_get(ctx); - blind = BN_CTX_get(ctx); - blindm = BN_CTX_get(ctx); - if (blindm == NULL) { + if ((ctx = BN_CTX_new()) == NULL + || (m = BN_new()) == NULL) { ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_MALLOC_FAILURE); goto err; } order = EC_GROUP_get0_order(group); - if (order == NULL) { - ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_EC_LIB); - goto err; - } i = BN_num_bits(order); /* * Need to truncate digest if it is too long: first truncate whole bytes. @@ -275,7 +251,7 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len, ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); goto err; } - /* If still too long truncate remaining bits with a shift */ + /* If still too long, truncate remaining bits with a shift */ if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) { ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); goto err; @@ -296,59 +272,27 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len, } /* - * The normal signature calculation is: - * - * s := k^-1 * (m + r * priv_key) mod order - * - * We will blind this to protect against side channel attacks - * - * s := k^-1 * blind^-1 * (blind * m + blind * r * priv_key) mod order + * With only one multiplicant being in Montgomery domain + * multiplication yields real result without post-conversion. + * Also note that all operations but last are performed with + * zero-padded vectors. Last operation, BN_mod_mul_montgomery + * below, returns user-visible value with removed zero padding. */ - - /* Generate a blinding value */ - do { - if (!BN_rand(blind, BN_num_bits(order) - 1, BN_RAND_TOP_ANY, - BN_RAND_BOTTOM_ANY)) - goto err; - } while (BN_is_zero(blind)); - BN_set_flags(blind, BN_FLG_CONSTTIME); - BN_set_flags(blindm, BN_FLG_CONSTTIME); - BN_set_flags(tmp, BN_FLG_CONSTTIME); - - /* tmp := blind * priv_key * r mod order */ - if (!BN_mod_mul(tmp, blind, priv_key, order, ctx)) { - ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_mul(tmp, tmp, ret->r, order, ctx)) { - ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); - goto err; - } - - /* blindm := blind * m mod order */ - if (!BN_mod_mul(blindm, blind, m, order, ctx)) { - ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); - goto err; - } - - /* s : = (blind * priv_key * r) + (blind * m) mod order */ - if (!BN_mod_add_quick(s, tmp, blindm, order)) { - ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); - goto err; - } - - /* s:= s * blind^-1 mod order */ - if (BN_mod_inverse(blind, blind, order, ctx) == NULL) { + if (!bn_to_mont_fixed_top(s, ret->r, group->mont_data, ctx) + || !bn_mul_mont_fixed_top(s, s, priv_key, group->mont_data, ctx)) { ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); goto err; } - if (!BN_mod_mul(s, s, blind, order, ctx)) { + if (!bn_mod_add_fixed_top(s, s, m, order)) { ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); goto err; } - - /* s := s * k^-1 mod order */ - if (!BN_mod_mul(s, s, ckinv, order, ctx)) { + /* + * |s| can still be larger than modulus, because |m| can be. In + * such case we count on Montgomery reduction to tie it up. + */ + if (!bn_to_mont_fixed_top(s, s, group->mont_data, ctx) + || !BN_mod_mul_montgomery(s, s, ckinv, group->mont_data, ctx)) { ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, ERR_R_BN_LIB); goto err; } @@ -362,11 +306,11 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len, ECerr(EC_F_OSSL_ECDSA_SIGN_SIG, EC_R_NEED_NEW_SETUP_VALUES); goto err; } - } else + } else { /* s != 0 => we have a valid signature */ break; - } - while (1); + } + } while (1); ok = 1; err: @@ -374,8 +318,8 @@ ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len, ECDSA_SIG_free(ret); ret = NULL; } - BN_CTX_end(ctx); BN_CTX_free(ctx); + BN_clear_free(m); BN_clear_free(kinv); return ret; } |