diff options
Diffstat (limited to 'openssl/crypto/ecdsa/ecs_ossl.c')
| -rw-r--r-- | openssl/crypto/ecdsa/ecs_ossl.c | 478 |
1 files changed, 478 insertions, 0 deletions
diff --git a/openssl/crypto/ecdsa/ecs_ossl.c b/openssl/crypto/ecdsa/ecs_ossl.c new file mode 100644 index 000000000..3ead1af94 --- /dev/null +++ b/openssl/crypto/ecdsa/ecs_ossl.c @@ -0,0 +1,478 @@ +/* crypto/ecdsa/ecs_ossl.c */ +/* + * Written by Nils Larsch for the OpenSSL project + */ +/* ==================================================================== + * Copyright (c) 1998-2004 The OpenSSL Project. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * 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 + * the documentation and/or other materials provided with the + * distribution. + * + * 3. All advertising materials mentioning features or use of this + * software must display the following acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" + * + * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to + * endorse or promote products derived from this software without + * prior written permission. For written permission, please contact + * openssl-core@OpenSSL.org. + * + * 5. Products derived from this software may not be called "OpenSSL" + * nor may "OpenSSL" appear in their names without prior written + * permission of the OpenSSL Project. + * + * 6. Redistributions of any form whatsoever must retain the following + * acknowledgment: + * "This product includes software developed by the OpenSSL Project + * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" + * + * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY + * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR + * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; + * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * ==================================================================== + * + * This product includes cryptographic software written by Eric Young + * (eay@cryptsoft.com). This product includes software written by Tim + * Hudson (tjh@cryptsoft.com). + * + */ + +#include "ecs_locl.h" +#include <openssl/err.h> +#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_METHOD openssl_ecdsa_meth = { + "OpenSSL ECDSA method", + ecdsa_do_sign, + ecdsa_sign_setup, + ecdsa_do_verify, +#if 0 + NULL, /* init */ + NULL, /* finish */ +#endif + 0, /* flags */ + NULL /* app_data */ +}; + +const ECDSA_METHOD *ECDSA_OpenSSL(void) +{ + return &openssl_ecdsa_meth; +} + +static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp, + 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; + + 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; + + 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)); + + /* 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; + } + } + 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; + } + } + 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); +} + + +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; + 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); + + 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; + + 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; + } + if (8 * dgst_len > BN_num_bits(order)) + { + /* XXX + * + * Should provide for optional hash truncation: + * Keep the BN_num_bits(order) leftmost bits of dgst + * (see March 2006 FIPS 186-3 draft, which has a few + * confusing errors in this part though) + */ + + ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, + ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); + goto err; + } + + if (!BN_bin2bn(dgst, dgst_len, m)) + { + 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); + + 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) +{ + int ret = -1; + 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; + } + + 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 (8 * dgst_len > BN_num_bits(order)) + { + /* XXX + * + * Should provide for optional hash truncation: + * Keep the BN_num_bits(order) leftmost bits of dgst + * (see March 2006 FIPS 186-3 draft, which has a few + * confusing errors in this part though) + */ + + ECDSAerr(ECDSA_F_ECDSA_DO_VERIFY, + ECDSA_R_DATA_TOO_LARGE_FOR_KEY_SIZE); + ret = 0; + 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 */ + if (!BN_bin2bn(dgst, dgst_len, m)) + { + 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; + } + } + 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; + } + } + + 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; +} |