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-rw-r--r--crypto/ecdsa/ecs_ossl.c721
1 files changed, 340 insertions, 381 deletions
diff --git a/crypto/ecdsa/ecs_ossl.c b/crypto/ecdsa/ecs_ossl.c
index 7725935610ed..4c5fa6b926e4 100644
--- a/crypto/ecdsa/ecs_ossl.c
+++ b/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 +61,382 @@
#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 (!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);
-
- if (group == NULL || priv_key == NULL || ecdsa == NULL)
- {
- ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER);
- return NULL;
- }
+ ecdsa = ecdsa_check(eckey);
+ group = EC_KEY_get0_group(eckey);
+ priv_key = EC_KEY_get0_private_key(eckey);
- ret = ECDSA_SIG_new();
- if (!ret)
- {
- ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE);
- return NULL;
- }
- s = ret->s;
+ if (group == NULL || priv_key == NULL || ecdsa == NULL) {
+ ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_PASSED_NULL_PARAMETER);
+ return NULL;
+ }
- 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;
- }
+ ret = ECDSA_SIG_new();
+ if (!ret) {
+ ECDSAerr(ECDSA_F_ECDSA_DO_SIGN, ERR_R_MALLOC_FAILURE);
+ return NULL;
+ }
+ s = ret->s;
- 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 ((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 (!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 (!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;
+ }
+ }
- 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;
+ 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)
+ 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;
}