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author | marha <marha@users.sourceforge.net> | 2015-02-22 21:39:56 +0100 |
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committer | marha <marha@users.sourceforge.net> | 2015-02-22 21:39:56 +0100 |
commit | 462f18c7b25fe3e467f837647d07ab0a78aa8d2b (patch) | |
tree | fc8013c0a1bac05a1945846c1697e973f4c35013 /openssl/crypto/ecdsa/ecs_ossl.c | |
parent | 36f711ee12b6dd5184198abed3aa551efb585587 (diff) | |
download | vcxsrv-462f18c7b25fe3e467f837647d07ab0a78aa8d2b.tar.gz vcxsrv-462f18c7b25fe3e467f837647d07ab0a78aa8d2b.tar.bz2 vcxsrv-462f18c7b25fe3e467f837647d07ab0a78aa8d2b.zip |
Merged origin/release (checked in because wanted to merge new stuff)
Diffstat (limited to 'openssl/crypto/ecdsa/ecs_ossl.c')
-rw-r--r-- | openssl/crypto/ecdsa/ecs_ossl.c | 743 |
1 files changed, 362 insertions, 381 deletions
diff --git a/openssl/crypto/ecdsa/ecs_ossl.c b/openssl/crypto/ecdsa/ecs_ossl.c index 772593561..dd769609b 100644 --- a/openssl/crypto/ecdsa/ecs_ossl.c +++ b/openssl/crypto/ecdsa/ecs_ossl.c @@ -10,7 +10,7 @@ * are met: * * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. + * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in @@ -61,423 +61,404 @@ #include <openssl/obj_mac.h> #include <openssl/bn.h> -static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen, - const BIGNUM *, const BIGNUM *, EC_KEY *eckey); -static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, - BIGNUM **rp); -static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, - const ECDSA_SIG *sig, EC_KEY *eckey); +static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dlen, + const BIGNUM *, const BIGNUM *, + EC_KEY *eckey); +static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, + BIGNUM **rp); +static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, + const ECDSA_SIG *sig, EC_KEY *eckey); static ECDSA_METHOD openssl_ecdsa_meth = { - "OpenSSL ECDSA method", - ecdsa_do_sign, - ecdsa_sign_setup, - ecdsa_do_verify, + "OpenSSL ECDSA method", + ecdsa_do_sign, + ecdsa_sign_setup, + ecdsa_do_verify, #if 0 - NULL, /* init */ - NULL, /* finish */ + NULL, /* init */ + NULL, /* finish */ #endif - 0, /* flags */ - NULL /* app_data */ + 0, /* flags */ + NULL /* app_data */ }; const ECDSA_METHOD *ECDSA_OpenSSL(void) { - return &openssl_ecdsa_meth; + return &openssl_ecdsa_meth; } static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, - BIGNUM **rp) + BIGNUM **rp) { - BN_CTX *ctx = NULL; - BIGNUM *k = NULL, *r = NULL, *order = NULL, *X = NULL; - EC_POINT *tmp_point=NULL; - const EC_GROUP *group; - int ret = 0; + BN_CTX *ctx = NULL; + BIGNUM *k = NULL, *r = NULL, *order = NULL, *X = NULL; + EC_POINT *tmp_point = NULL; + const EC_GROUP *group; + int ret = 0; + + if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER); + return 0; + } - if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_PASSED_NULL_PARAMETER); - return 0; - } + if (ctx_in == NULL) { + if ((ctx = BN_CTX_new()) == NULL) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE); + return 0; + } + } else + ctx = ctx_in; - if (ctx_in == NULL) - { - if ((ctx = BN_CTX_new()) == NULL) - { - ECDSAerr(ECDSA_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 */ + order = BN_new(); + X = BN_new(); + if (!k || !r || !order || !X) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE); + goto err; + } + if ((tmp_point = EC_POINT_new(group)) == NULL) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); + goto err; + } + if (!EC_GROUP_get_order(group, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); + goto err; + } - k = BN_new(); /* this value is later returned in *kinvp */ - r = BN_new(); /* this value is later returned in *rp */ - order = BN_new(); - X = BN_new(); - if (!k || !r || !order || !X) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_MALLOC_FAILURE); - goto err; - } - if ((tmp_point = EC_POINT_new(group)) == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); - goto err; - } - if (!EC_GROUP_get_order(group, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); - goto err; - } - - do - { - /* get random k */ - do - if (!BN_rand_range(k, order)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, - ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); - goto err; - } - while (BN_is_zero(k)); + do { + /* get random k */ + do + if (!BN_rand_range(k, order)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, + ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); + goto err; + } + while (BN_is_zero(k)) ; - /* We do not want timing information to leak the length of k, - * so we compute G*k using an equivalent scalar of fixed - * bit-length. */ + /* + * We do not want timing information to leak the length of k, so we + * compute G*k using an equivalent scalar of fixed bit-length. + */ - if (!BN_add(k, k, order)) goto err; - if (BN_num_bits(k) <= BN_num_bits(order)) - if (!BN_add(k, k, order)) goto err; + if (!BN_add(k, k, order)) + goto err; + if (BN_num_bits(k) <= BN_num_bits(order)) + if (!BN_add(k, k, order)) + goto err; - /* compute r the x-coordinate of generator * k */ - if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); - goto err; - } - 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)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,ERR_R_EC_LIB); - goto err; - } - } + /* compute r the x-coordinate of generator * k */ + if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); + goto err; + } + 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)) { + ECDSAerr(ECDSA_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)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP,ERR_R_EC_LIB); - goto err; - } - } + else { /* NID_X9_62_characteristic_two_field */ + + if (!EC_POINT_get_affine_coordinates_GF2m(group, + tmp_point, X, NULL, + ctx)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_EC_LIB); + goto err; + } + } #endif - if (!BN_nnmod(r, X, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); - goto err; - } - } - while (BN_is_zero(r)); + if (!BN_nnmod(r, X, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); + goto err; + } + } + while (BN_is_zero(r)); - /* compute the inverse of k */ - if (!BN_mod_inverse(k, k, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); - goto err; - } - /* clear old values if necessary */ - if (*rp != NULL) - BN_clear_free(*rp); - if (*kinvp != NULL) - BN_clear_free(*kinvp); - /* save the pre-computed values */ - *rp = r; - *kinvp = k; - ret = 1; -err: - if (!ret) - { - if (k != NULL) BN_clear_free(k); - if (r != NULL) BN_clear_free(r); - } - if (ctx_in == NULL) - BN_CTX_free(ctx); - if (order != NULL) - BN_free(order); - if (tmp_point != NULL) - EC_POINT_free(tmp_point); - if (X) - BN_clear_free(X); - return(ret); -} + /* compute the inverse of k */ + if (EC_GROUP_get_mont_data(group) != NULL) { + /* + * We want inverse in constant time, therefore we utilize the fact + * order must be prime and use Fermats Little Theorem instead. + */ + if (!BN_set_word(X, 2)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_sub(X, order, X, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); + goto err; + } + BN_set_flags(X, BN_FLG_CONSTTIME); + if (!BN_mod_exp_mont_consttime + (k, k, X, order, ctx, EC_GROUP_get_mont_data(group))) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); + goto err; + } + } else { + if (!BN_mod_inverse(k, k, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_SIGN_SETUP, ERR_R_BN_LIB); + goto err; + } + } + /* clear old values if necessary */ + if (*rp != NULL) + BN_clear_free(*rp); + if (*kinvp != NULL) + BN_clear_free(*kinvp); + /* save the pre-computed values */ + *rp = r; + *kinvp = k; + ret = 1; + err: + if (!ret) { + if (k != NULL) + BN_clear_free(k); + if (r != NULL) + BN_clear_free(r); + } + if (ctx_in == NULL) + BN_CTX_free(ctx); + if (order != NULL) + BN_free(order); + if (tmp_point != NULL) + EC_POINT_free(tmp_point); + if (X) + BN_clear_free(X); + return (ret); +} -static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, - const BIGNUM *in_kinv, const BIGNUM *in_r, EC_KEY *eckey) +static ECDSA_SIG *ecdsa_do_sign(const unsigned char *dgst, int dgst_len, + const BIGNUM *in_kinv, const BIGNUM *in_r, + EC_KEY *eckey) { - int ok = 0, i; - BIGNUM *kinv=NULL, *s, *m=NULL,*tmp=NULL,*order=NULL; - const BIGNUM *ckinv; - BN_CTX *ctx = NULL; - const EC_GROUP *group; - ECDSA_SIG *ret; - ECDSA_DATA *ecdsa; - const BIGNUM *priv_key; + int ok = 0, i; + BIGNUM *kinv = NULL, *s, *m = NULL, *tmp = NULL, *order = NULL; + const BIGNUM *ckinv; + BN_CTX *ctx = NULL; + const EC_GROUP *group; + ECDSA_SIG *ret; + ECDSA_DATA *ecdsa; + const BIGNUM *priv_key; + + ecdsa = ecdsa_check(eckey); + group = EC_KEY_get0_group(eckey); + priv_key = EC_KEY_get0_private_key(eckey); - ecdsa = ecdsa_check(eckey); - group = EC_KEY_get0_group(eckey); - priv_key = EC_KEY_get0_private_key(eckey); - - if (group == NULL || priv_key == NULL || ecdsa == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER); - return NULL; - } + if (group == NULL || priv_key == NULL || ecdsa == NULL) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER); + return NULL; + } - ret = ECDSA_SIG_new(); - if (!ret) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); - return NULL; - } - s = ret->s; + ret = ECDSA_SIG_new(); + if (!ret) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); + return NULL; + } + s = ret->s; - if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL || - (tmp = BN_new()) == NULL || (m = BN_new()) == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); - goto err; - } + if ((ctx = BN_CTX_new()) == NULL || (order = BN_new()) == NULL || + (tmp = BN_new()) == NULL || (m = BN_new()) == NULL) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); + goto err; + } - if (!EC_GROUP_get_order(group, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_EC_LIB); - goto err; - } - i = BN_num_bits(order); - /* Need to truncate digest if it is too long: first truncate whole - * bytes. - */ - if (8 * dgst_len > i) - dgst_len = (i + 7)/8; - if (!BN_bin2bn(dgst, dgst_len, m)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); - goto err; - } - /* If still too long truncate remaining bits with a shift */ - if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); - goto err; - } - do - { - if (in_kinv == NULL || in_r == NULL) - { - if (!ECDSA_sign_setup(eckey, ctx, &kinv, &ret->r)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN,ERR_R_ECDSA_LIB); - goto err; - } - ckinv = kinv; - } - else - { - ckinv = in_kinv; - if (BN_copy(ret->r, in_r) == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); - goto err; - } - } + if (!EC_GROUP_get_order(group, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_EC_LIB); + goto err; + } + i = BN_num_bits(order); + /* + * Need to truncate digest if it is too long: first truncate whole bytes. + */ + if (8 * dgst_len > i) + dgst_len = (i + 7) / 8; + if (!BN_bin2bn(dgst, dgst_len, m)) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); + goto err; + } + /* If still too long truncate remaining bits with a shift */ + if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); + goto err; + } + do { + if (in_kinv == NULL || in_r == NULL) { + if (!ECDSA_sign_setup(eckey, ctx, &kinv, &ret->r)) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_ECDSA_LIB); + goto err; + } + ckinv = kinv; + } else { + ckinv = in_kinv; + if (BN_copy(ret->r, in_r) == NULL) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE); + goto err; + } + } - if (!BN_mod_mul(tmp, priv_key, ret->r, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_add_quick(s, tmp, m, order)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_mul(s, s, ckinv, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); - goto err; - } - if (BN_is_zero(s)) - { - /* if kinv and r have been supplied by the caller - * don't to generate new kinv and r values */ - if (in_kinv != NULL && in_r != NULL) - { - ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ECDSA_R_NEED_NEW_SETUP_VALUES); - goto err; - } - } - else - /* s != 0 => we have a valid signature */ - break; - } - while (1); + if (!BN_mod_mul(tmp, priv_key, ret->r, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_add_quick(s, tmp, m, order)) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_mul(s, s, ckinv, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_BN_LIB); + goto err; + } + if (BN_is_zero(s)) { + /* + * if kinv and r have been supplied by the caller don't to + * generate new kinv and r values + */ + if (in_kinv != NULL && in_r != NULL) { + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, + ECDSA_R_NEED_NEW_SETUP_VALUES); + goto err; + } + } else + /* s != 0 => we have a valid signature */ + break; + } + while (1); - ok = 1; -err: - if (!ok) - { - ECDSA_SIG_free(ret); - ret = NULL; - } - if (ctx) - BN_CTX_free(ctx); - if (m) - BN_clear_free(m); - if (tmp) - BN_clear_free(tmp); - if (order) - BN_free(order); - if (kinv) - BN_clear_free(kinv); - return ret; + ok = 1; + err: + if (!ok) { + ECDSA_SIG_free(ret); + ret = NULL; + } + if (ctx) + BN_CTX_free(ctx); + if (m) + BN_clear_free(m); + if (tmp) + BN_clear_free(tmp); + if (order) + BN_free(order); + if (kinv) + BN_clear_free(kinv); + return ret; } static int ecdsa_do_verify(const unsigned char *dgst, int dgst_len, - const ECDSA_SIG *sig, EC_KEY *eckey) + const ECDSA_SIG *sig, EC_KEY *eckey) { - int ret = -1, i; - BN_CTX *ctx; - BIGNUM *order, *u1, *u2, *m, *X; - EC_POINT *point = NULL; - const EC_GROUP *group; - const EC_POINT *pub_key; + int ret = -1, i; + BN_CTX *ctx; + BIGNUM *order, *u1, *u2, *m, *X; + EC_POINT *point = NULL; + const EC_GROUP *group; + const EC_POINT *pub_key; + + /* check input values */ + if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL || + (pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_MISSING_PARAMETERS); + return -1; + } - /* check input values */ - if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL || - (pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_MISSING_PARAMETERS); - return -1; - } + ctx = BN_CTX_new(); + if (!ctx) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE); + return -1; + } + BN_CTX_start(ctx); + order = BN_CTX_get(ctx); + u1 = BN_CTX_get(ctx); + u2 = BN_CTX_get(ctx); + m = BN_CTX_get(ctx); + X = BN_CTX_get(ctx); + if (!X) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } - ctx = BN_CTX_new(); - if (!ctx) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE); - return -1; - } - BN_CTX_start(ctx); - order = BN_CTX_get(ctx); - u1 = BN_CTX_get(ctx); - u2 = BN_CTX_get(ctx); - m = BN_CTX_get(ctx); - X = BN_CTX_get(ctx); - if (!X) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } - - if (!EC_GROUP_get_order(group, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); - goto err; - } + if (!EC_GROUP_get_order(group, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); + goto err; + } - if (BN_is_zero(sig->r) || BN_is_negative(sig->r) || - BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) || - BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE); - ret = 0; /* signature is invalid */ - goto err; - } - /* calculate tmp1 = inv(S) mod order */ - if (!BN_mod_inverse(u2, sig->s, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } - /* digest -> m */ - i = BN_num_bits(order); - /* Need to truncate digest if it is too long: first truncate whole - * bytes. - */ - if (8 * dgst_len > i) - dgst_len = (i + 7)/8; - if (!BN_bin2bn(dgst, dgst_len, m)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } - /* If still too long truncate remaining bits with a shift */ - if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } - /* u1 = m * tmp mod order */ - if (!BN_mod_mul(u1, m, u2, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } - /* u2 = r * w mod q */ - if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } + if (BN_is_zero(sig->r) || BN_is_negative(sig->r) || + BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) || + BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ECDSA_R_BAD_SIGNATURE); + ret = 0; /* signature is invalid */ + goto err; + } + /* calculate tmp1 = inv(S) mod order */ + if (!BN_mod_inverse(u2, sig->s, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } + /* digest -> m */ + i = BN_num_bits(order); + /* + * Need to truncate digest if it is too long: first truncate whole bytes. + */ + if (8 * dgst_len > i) + dgst_len = (i + 7) / 8; + if (!BN_bin2bn(dgst, dgst_len, m)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } + /* If still too long truncate remaining bits with a shift */ + if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } + /* u1 = m * tmp mod order */ + if (!BN_mod_mul(u1, m, u2, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } + /* u2 = r * w mod q */ + if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } - if ((point = EC_POINT_new(group)) == NULL) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE); - goto err; - } - if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); - goto err; - } - if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == NID_X9_62_prime_field) - { - if (!EC_POINT_get_affine_coordinates_GFp(group, - point, X, NULL, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); - goto err; - } - } + if ((point = EC_POINT_new(group)) == NULL) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_MALLOC_FAILURE); + goto err; + } + if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); + goto err; + } + if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) == + NID_X9_62_prime_field) { + if (!EC_POINT_get_affine_coordinates_GFp(group, point, X, NULL, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, 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, - point, X, NULL, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); - goto err; - } - } -#endif - if (!BN_nnmod(u1, X, order, ctx)) - { - ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); - goto err; - } - /* if the signature is correct u1 is equal to sig->r */ - ret = (BN_ucmp(u1, sig->r) == 0); -err: - BN_CTX_end(ctx); - BN_CTX_free(ctx); - if (point) - EC_POINT_free(point); - return ret; + else { /* NID_X9_62_characteristic_two_field */ + + if (!EC_POINT_get_affine_coordinates_GF2m(group, point, X, NULL, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_EC_LIB); + goto err; + } + } +#endif + if (!BN_nnmod(u1, X, order, ctx)) { + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, ERR_R_BN_LIB); + goto err; + } + /* if the signature is correct u1 is equal to sig->r */ + ret = (BN_ucmp(u1, sig->r) == 0); + err: + BN_CTX_end(ctx); + BN_CTX_free(ctx); + if (point) + EC_POINT_free(point); + return ret; } |