diff options
Diffstat (limited to 'src/crypto/ecdsa/ecdsa.c')
-rw-r--r-- | src/crypto/ecdsa/ecdsa.c | 119 |
1 files changed, 69 insertions, 50 deletions
diff --git a/src/crypto/ecdsa/ecdsa.c b/src/crypto/ecdsa/ecdsa.c index b71799e..8403d60 100644 --- a/src/crypto/ecdsa/ecdsa.c +++ b/src/crypto/ecdsa/ecdsa.c @@ -52,9 +52,11 @@ #include <openssl/ecdsa.h> +#include <assert.h> #include <string.h> #include <openssl/bn.h> +#include <openssl/bytestring.h> #include <openssl/err.h> #include <openssl/mem.h> @@ -81,16 +83,18 @@ int ECDSA_verify(int type, const uint8_t *digest, size_t digest_len, return eckey->ecdsa_meth->verify(digest, digest_len, sig, sig_len, eckey); } - s = ECDSA_SIG_new(); - const uint8_t *sigp = sig; - if (s == NULL || d2i_ECDSA_SIG(&s, &sigp, sig_len) == NULL || - sigp != sig + sig_len) { + /* Decode the ECDSA signature. */ + s = ECDSA_SIG_from_bytes(sig, sig_len); + if (s == NULL) { goto err; } - /* Ensure that the signature uses DER and doesn't have trailing garbage. */ - const int der_len = i2d_ECDSA_SIG(s, &der); - if (der_len < 0 || (size_t) der_len != sig_len || memcmp(sig, der, sig_len)) { + /* Defend against potential laxness in the DER parser. */ + size_t der_len; + if (!ECDSA_SIG_to_bytes(&der, &der_len, s) || + der_len != sig_len || memcmp(sig, der, sig_len) != 0) { + /* This should never happen. crypto/bytestring is strictly DER. */ + OPENSSL_PUT_ERROR(ECDSA, ERR_R_INTERNAL_ERROR); goto err; } @@ -116,14 +120,14 @@ static int digest_to_bn(BIGNUM *out, const uint8_t *digest, size_t digest_len, digest_len = (num_bits + 7) / 8; } if (!BN_bin2bn(digest, digest_len, out)) { - OPENSSL_PUT_ERROR(ECDSA, digest_to_bn, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); return 0; } /* If still too long truncate remaining bits with a shift */ if ((8 * digest_len > num_bits) && !BN_rshift(out, out, 8 - (num_bits & 0x7))) { - OPENSSL_PUT_ERROR(ECDSA, digest_to_bn, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); return 0; } @@ -145,7 +149,7 @@ int ECDSA_do_verify(const uint8_t *digest, size_t digest_len, const EC_POINT *pub_key; if (eckey->ecdsa_meth && eckey->ecdsa_meth->verify) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ECDSA_R_NOT_IMPLEMENTED); + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_NOT_IMPLEMENTED); return 0; } @@ -153,13 +157,13 @@ int ECDSA_do_verify(const uint8_t *digest, size_t digest_len, if ((group = EC_KEY_get0_group(eckey)) == NULL || (pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ECDSA_R_MISSING_PARAMETERS); + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_MISSING_PARAMETERS); return 0; } ctx = BN_CTX_new(); if (!ctx) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE); return 0; } BN_CTX_start(ctx); @@ -168,26 +172,26 @@ int ECDSA_do_verify(const uint8_t *digest, size_t digest_len, u2 = BN_CTX_get(ctx); m = BN_CTX_get(ctx); X = BN_CTX_get(ctx); - if (!X) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_BN_LIB); + if (order == NULL || u1 == NULL || u2 == NULL || m == NULL || X == NULL) { + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } if (!EC_GROUP_get_order(group, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, 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) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ECDSA_R_BAD_SIGNATURE); + OPENSSL_PUT_ERROR(ECDSA, 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)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } if (!digest_to_bn(m, digest, digest_len, order)) { @@ -195,30 +199,30 @@ int ECDSA_do_verify(const uint8_t *digest, size_t digest_len, } /* u1 = m * tmp mod order */ if (!BN_mod_mul(u1, m, u2, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } /* u2 = r * w mod q */ if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } point = EC_POINT_new(group); if (point == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE); goto err; } if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } if (!EC_POINT_get_affine_coordinates_GFp(group, point, X, NULL, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } if (!BN_nnmod(u1, X, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_verify, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } /* if the signature is correct u1 is equal to sig->r */ @@ -241,13 +245,13 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, int ret = 0; if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_PASSED_NULL_PARAMETER); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_PASSED_NULL_PARAMETER); return 0; } if (ctx_in == NULL) { if ((ctx = BN_CTX_new()) == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE); return 0; } } else { @@ -259,16 +263,16 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, order = BN_new(); X = BN_new(); if (!k || !r || !order || !X) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE); goto err; } tmp_point = EC_POINT_new(group); if (tmp_point == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } if (!EC_GROUP_get_order(group, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } @@ -286,8 +290,7 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, ok = BN_rand_range(k, order); } if (!ok) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, - ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); goto err; } } while (BN_is_zero(k)); @@ -307,23 +310,23 @@ static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, /* compute r the x-coordinate of generator * k */ if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } if (!EC_POINT_get_affine_coordinates_GFp(group, tmp_point, X, NULL, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } if (!BN_nnmod(r, X, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } } while (BN_is_zero(r)); /* compute the inverse of k */ if (!BN_mod_inverse(k, k, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ecdsa_sign_setup, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } /* clear old values if necessary */ @@ -365,7 +368,7 @@ ECDSA_SIG *ECDSA_do_sign_ex(const uint8_t *digest, size_t digest_len, const BIGNUM *priv_key; if (eckey->ecdsa_meth && eckey->ecdsa_meth->sign) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ECDSA_R_NOT_IMPLEMENTED); + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_NOT_IMPLEMENTED); return NULL; } @@ -373,25 +376,25 @@ ECDSA_SIG *ECDSA_do_sign_ex(const uint8_t *digest, size_t digest_len, priv_key = EC_KEY_get0_private_key(eckey); if (group == NULL || priv_key == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_PASSED_NULL_PARAMETER); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_PASSED_NULL_PARAMETER); return NULL; } ret = ECDSA_SIG_new(); if (!ret) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, 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) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE); goto err; } if (!EC_GROUP_get_order(group, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_EC_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_EC_LIB); goto err; } if (!digest_to_bn(m, digest, digest_len, order)) { @@ -400,35 +403,35 @@ ECDSA_SIG *ECDSA_do_sign_ex(const uint8_t *digest, size_t digest_len, for (;;) { if (in_kinv == NULL || in_r == NULL) { if (!ecdsa_sign_setup(eckey, ctx, &kinv, &ret->r, digest, digest_len)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_ECDSA_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_ECDSA_LIB); goto err; } ckinv = kinv; } else { ckinv = in_kinv; if (BN_copy(ret->r, in_r) == NULL) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_MALLOC_FAILURE); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_MALLOC_FAILURE); goto err; } } if (!BN_mod_mul(tmp, priv_key, ret->r, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } if (!BN_mod_add_quick(s, tmp, m, order)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, ERR_R_BN_LIB); goto err; } if (!BN_mod_mul(s, s, ckinv, order, ctx)) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ERR_R_BN_LIB); + OPENSSL_PUT_ERROR(ECDSA, 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) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_do_sign_ex, ECDSA_R_NEED_NEW_SETUP_VALUES); + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_NEED_NEW_SETUP_VALUES); goto err; } } else { @@ -455,20 +458,36 @@ err: int ECDSA_sign_ex(int type, const uint8_t *digest, size_t digest_len, uint8_t *sig, unsigned int *sig_len, const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey) { + int ret = 0; ECDSA_SIG *s = NULL; if (eckey->ecdsa_meth && eckey->ecdsa_meth->sign) { - OPENSSL_PUT_ERROR(ECDSA, ECDSA_sign_ex, ECDSA_R_NOT_IMPLEMENTED); + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_NOT_IMPLEMENTED); *sig_len = 0; - return 0; + goto err; } s = ECDSA_do_sign_ex(digest, digest_len, kinv, r, eckey); if (s == NULL) { *sig_len = 0; - return 0; + goto err; } - *sig_len = i2d_ECDSA_SIG(s, &sig); + + CBB cbb; + CBB_zero(&cbb); + size_t len; + if (!CBB_init_fixed(&cbb, sig, ECDSA_size(eckey)) || + !ECDSA_SIG_marshal(&cbb, s) || + !CBB_finish(&cbb, NULL, &len)) { + OPENSSL_PUT_ERROR(ECDSA, ECDSA_R_ENCODE_ERROR); + CBB_cleanup(&cbb); + *sig_len = 0; + goto err; + } + *sig_len = (unsigned)len; + ret = 1; + +err: ECDSA_SIG_free(s); - return 1; + return ret; } |