From: tb Date: Wed, 5 Jul 2023 12:18:21 +0000 (+0000) Subject: Merge ECDSA code that will stay into ecdsa.c X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=b4a65d296e4a336dac6770b161f113e27d4d5d5e;p=openbsd Merge ECDSA code that will stay into ecdsa.c discussed with jsing --- diff --git a/lib/libcrypto/Makefile b/lib/libcrypto/Makefile index d67bb4431af..bf20491fbc8 100644 --- a/lib/libcrypto/Makefile +++ b/lib/libcrypto/Makefile @@ -1,4 +1,4 @@ -# $OpenBSD: Makefile,v 1.133 2023/06/29 06:12:04 tb Exp $ +# $OpenBSD: Makefile,v 1.134 2023/07/05 12:18:21 tb Exp $ LIB= crypto LIBREBUILD=y @@ -357,10 +357,9 @@ SRCS+= ech_key.c SRCS+= ech_lib.c # ecdsa/ -SRCS+= ecs_asn1.c SRCS+= ecs_err.c SRCS+= ecs_lib.c -SRCS+= ecs_ossl.c +SRCS+= ecdsa.c # engine/ SRCS+= eng_all.c diff --git a/lib/libcrypto/ecdsa/ecdsa.c b/lib/libcrypto/ecdsa/ecdsa.c new file mode 100644 index 00000000000..c831e9f7160 --- /dev/null +++ b/lib/libcrypto/ecdsa/ecdsa.c @@ -0,0 +1,821 @@ +/* $OpenBSD: ecdsa.c,v 1.1 2023/07/05 12:18:21 tb Exp $ */ +/* ==================================================================== + * Copyright (c) 2000-2002 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 + * licensing@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 + +#include + +#include +#include +#include +#include +#include + +#include "bn_local.h" +#include "ec_local.h" +#include "ecdsa_local.h" + +static const ASN1_TEMPLATE ECDSA_SIG_seq_tt[] = { + { + .flags = 0, + .tag = 0, + .offset = offsetof(ECDSA_SIG, r), + .field_name = "r", + .item = &BIGNUM_it, + }, + { + .flags = 0, + .tag = 0, + .offset = offsetof(ECDSA_SIG, s), + .field_name = "s", + .item = &BIGNUM_it, + }, +}; + +const ASN1_ITEM ECDSA_SIG_it = { + .itype = ASN1_ITYPE_SEQUENCE, + .utype = V_ASN1_SEQUENCE, + .templates = ECDSA_SIG_seq_tt, + .tcount = sizeof(ECDSA_SIG_seq_tt) / sizeof(ASN1_TEMPLATE), + .funcs = NULL, + .size = sizeof(ECDSA_SIG), + .sname = "ECDSA_SIG", +}; + +ECDSA_SIG *ECDSA_SIG_new(void); +void ECDSA_SIG_free(ECDSA_SIG *a); +ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **a, const unsigned char **in, long len); +int i2d_ECDSA_SIG(const ECDSA_SIG *a, unsigned char **out); + +ECDSA_SIG * +d2i_ECDSA_SIG(ECDSA_SIG **a, const unsigned char **in, long len) +{ + return (ECDSA_SIG *)ASN1_item_d2i((ASN1_VALUE **)a, in, len, + &ECDSA_SIG_it); +} + +int +i2d_ECDSA_SIG(const ECDSA_SIG *a, unsigned char **out) +{ + return ASN1_item_i2d((ASN1_VALUE *)a, out, &ECDSA_SIG_it); +} + +ECDSA_SIG * +ECDSA_SIG_new(void) +{ + return (ECDSA_SIG *)ASN1_item_new(&ECDSA_SIG_it); +} + +void +ECDSA_SIG_free(ECDSA_SIG *a) +{ + ASN1_item_free((ASN1_VALUE *)a, &ECDSA_SIG_it); +} + +void +ECDSA_SIG_get0(const ECDSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps) +{ + if (pr != NULL) + *pr = sig->r; + if (ps != NULL) + *ps = sig->s; +} + +const BIGNUM * +ECDSA_SIG_get0_r(const ECDSA_SIG *sig) +{ + return sig->r; +} + +const BIGNUM * +ECDSA_SIG_get0_s(const ECDSA_SIG *sig) +{ + return sig->s; +} + +int +ECDSA_SIG_set0(ECDSA_SIG *sig, BIGNUM *r, BIGNUM *s) +{ + if (r == NULL || s == NULL) + return 0; + + BN_free(sig->r); + BN_free(sig->s); + sig->r = r; + sig->s = s; + return 1; +} + +/* + * FIPS 186-5, section 6.4.1, step 2: convert hashed message into an integer. + * Use the order_bits leftmost bits if it exceeds the group order. + */ +static int +ecdsa_prepare_digest(const unsigned char *digest, int digest_len, + const EC_KEY *key, BIGNUM *e) +{ + const EC_GROUP *group; + int digest_bits, order_bits; + + if (!BN_bin2bn(digest, digest_len, e)) { + ECDSAerror(ERR_R_BN_LIB); + return 0; + } + + if ((group = EC_KEY_get0_group(key)) == NULL) + return 0; + order_bits = EC_GROUP_order_bits(group); + + digest_bits = 8 * digest_len; + if (digest_bits <= order_bits) + return 1; + + return BN_rshift(e, e, digest_bits - order_bits); +} + +int +ecdsa_sign(int type, const unsigned char *digest, int digest_len, + unsigned char *signature, unsigned int *signature_len, const BIGNUM *kinv, + const BIGNUM *r, EC_KEY *key) +{ + ECDSA_SIG *sig; + int out_len = 0; + int ret = 0; + + if ((sig = ECDSA_do_sign_ex(digest, digest_len, kinv, r, key)) == NULL) + goto err; + + if ((out_len = i2d_ECDSA_SIG(sig, &signature)) < 0) { + out_len = 0; + goto err; + } + + ret = 1; + + err: + *signature_len = out_len; + ECDSA_SIG_free(sig); + + return ret; +} + +/* + * FIPS 186-5, section 6.4.1, steps 3-8 and 11: Generate k, calculate r and + * kinv, and clear it. If r == 0, try again with a new random k. + */ + +int +ecdsa_sign_setup(EC_KEY *key, BN_CTX *in_ctx, BIGNUM **out_kinv, BIGNUM **out_r) +{ + const EC_GROUP *group; + EC_POINT *point = NULL; + BN_CTX *ctx = NULL; + BIGNUM *k = NULL, *r = NULL; + const BIGNUM *order; + BIGNUM *x; + int order_bits; + int ret = 0; + + BN_free(*out_kinv); + *out_kinv = NULL; + + BN_free(*out_r); + *out_r = NULL; + + if (key == NULL) { + ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); + goto err; + } + if ((group = EC_KEY_get0_group(key)) == NULL) { + ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); + goto err; + } + + if ((k = BN_new()) == NULL) + goto err; + if ((r = BN_new()) == NULL) + goto err; + + if ((ctx = in_ctx) == NULL) + ctx = BN_CTX_new(); + if (ctx == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + + BN_CTX_start(ctx); + + if ((x = BN_CTX_get(ctx)) == NULL) + goto err; + + if ((point = EC_POINT_new(group)) == NULL) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + if ((order = EC_GROUP_get0_order(group)) == NULL) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + + if (BN_cmp(order, BN_value_one()) <= 0) { + ECDSAerror(EC_R_INVALID_GROUP_ORDER); + goto err; + } + + /* Reject curves with an order that is smaller than 80 bits. */ + if ((order_bits = BN_num_bits(order)) < 80) { + ECDSAerror(EC_R_INVALID_GROUP_ORDER); + goto err; + } + + /* Preallocate space. */ + if (!BN_set_bit(k, order_bits) || + !BN_set_bit(r, order_bits) || + !BN_set_bit(x, order_bits)) + goto err; + + /* Step 11: repeat until r != 0. */ + do { + /* Step 3: generate random k. */ + if (!bn_rand_interval(k, BN_value_one(), order)) { + ECDSAerror(ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); + goto err; + } + + /* + * 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 unconditionally perform both of these additions to prevent + * a small timing information leakage. We then choose the sum + * that is one bit longer than the order. This guarantees the + * code path used in the constant time implementations + * elsewhere. + * + * TODO: revisit the bn_copy aiming for a memory access agnostic + * conditional copy. + */ + if (!BN_add(r, k, order) || + !BN_add(x, r, order) || + !bn_copy(k, BN_num_bits(r) > order_bits ? r : x)) + goto err; + + BN_set_flags(k, BN_FLG_CONSTTIME); + + /* Step 5: P = k * G. */ + if (!EC_POINT_mul(group, point, k, NULL, NULL, ctx)) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + /* Steps 6 (and 7): from P = (x, y) retain the x-coordinate. */ + if (!EC_POINT_get_affine_coordinates(group, point, x, NULL, + ctx)) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + /* Step 8: r = x (mod order). */ + if (!BN_nnmod(r, x, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + } while (BN_is_zero(r)); + + /* Step 4: calculate kinv. */ + if (BN_mod_inverse_ct(k, k, order, ctx) == NULL) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + + *out_kinv = k; + k = NULL; + + *out_r = r; + r = NULL; + + ret = 1; + + err: + BN_CTX_end(ctx); + if (ctx != in_ctx) + BN_CTX_free(ctx); + BN_free(k); + BN_free(r); + EC_POINT_free(point); + + return ret; +} + +/* + * FIPS 186-5, section 6.4.1, step 9: compute s = inv(k)(e + xr) mod order. + * In order to reduce the possibility of a side-channel attack, the following + * is calculated using a random blinding value b in [1, order): + * s = inv(b)(be + bxr)inv(k) mod order. + */ + +static int +ecdsa_compute_s(BIGNUM **out_s, const BIGNUM *e, const BIGNUM *kinv, + const BIGNUM *r, const EC_KEY *key, BN_CTX *ctx) +{ + const EC_GROUP *group; + const BIGNUM *order, *priv_key; + BIGNUM *b, *binv, *be, *bxr; + BIGNUM *s = NULL; + int ret = 0; + + *out_s = NULL; + + BN_CTX_start(ctx); + + if ((group = EC_KEY_get0_group(key)) == NULL) { + ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); + goto err; + } + if ((order = EC_GROUP_get0_order(group)) == NULL) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + if ((priv_key = EC_KEY_get0_private_key(key)) == NULL) { + ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); + goto err; + } + + if ((b = BN_CTX_get(ctx)) == NULL) + goto err; + if ((binv = BN_CTX_get(ctx)) == NULL) + goto err; + if ((be = BN_CTX_get(ctx)) == NULL) + goto err; + if ((bxr = BN_CTX_get(ctx)) == NULL) + goto err; + + if ((s = BN_new()) == NULL) + goto err; + + /* + * In a valid ECDSA signature, r must be in [1, order). Since r can be + * caller provided - either directly or by replacing sign_setup() - we + * can't rely on this being the case. + */ + if (BN_cmp(r, BN_value_one()) < 0 || BN_cmp(r, order) >= 0) { + ECDSAerror(ECDSA_R_BAD_SIGNATURE); + goto err; + } + + if (!bn_rand_interval(b, BN_value_one(), order)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + + if (BN_mod_inverse_ct(binv, b, order, ctx) == NULL) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + + if (!BN_mod_mul(bxr, b, priv_key, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_mul(bxr, bxr, r, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_mul(be, b, e, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_add(s, be, bxr, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + /* s = b(e + xr)k^-1 */ + if (!BN_mod_mul(s, s, kinv, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + /* s = (e + xr)k^-1 */ + if (!BN_mod_mul(s, s, binv, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + + /* Step 11: if s == 0 start over. */ + if (!BN_is_zero(s)) { + *out_s = s; + s = NULL; + } + + ret = 1; + + err: + BN_CTX_end(ctx); + BN_free(s); + + return ret; +} + +/* + * It is too expensive to check curve parameters on every sign operation. + * Instead, cap the number of retries. A single retry is very unlikely, so + * allowing 32 retries is amply enough. + */ +#define ECDSA_MAX_SIGN_ITERATIONS 32 + +/* + * FIPS 186-5: Section 6.4.1: ECDSA signature generation, steps 2-12. + * The caller provides the hash of the message, thus performs step 1. + * Step 10, zeroing k and kinv, is done by BN_free(). + */ + +ECDSA_SIG * +ecdsa_sign_sig(const unsigned char *digest, int digest_len, + const BIGNUM *in_kinv, const BIGNUM *in_r, EC_KEY *key) +{ + BN_CTX *ctx = NULL; + BIGNUM *kinv = NULL, *r = NULL, *s = NULL; + BIGNUM *e; + int caller_supplied_values = 0; + int attempts = 0; + ECDSA_SIG *sig = NULL; + + if ((ctx = BN_CTX_new()) == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + + BN_CTX_start(ctx); + + if ((e = BN_CTX_get(ctx)) == NULL) + goto err; + + /* Step 2: convert hash into an integer. */ + if (!ecdsa_prepare_digest(digest, digest_len, key, e)) + goto err; + + if (in_kinv != NULL && in_r != NULL) { + /* + * Use the caller's kinv and r. Don't call ECDSA_sign_setup(). + * If we're unable to compute a valid signature, the caller + * must provide new values. + */ + caller_supplied_values = 1; + + if ((kinv = BN_dup(in_kinv)) == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + if ((r = BN_dup(in_r)) == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + } + + do { + /* Steps 3-8: calculate kinv and r. */ + if (!caller_supplied_values) { + if (!ECDSA_sign_setup(key, ctx, &kinv, &r)) { + ECDSAerror(ERR_R_ECDSA_LIB); + goto err; + } + } + + /* + * Steps 9 and 11: if s is non-NULL, we have a valid signature. + */ + if (!ecdsa_compute_s(&s, e, kinv, r, key, ctx)) + goto err; + if (s != NULL) + break; + + if (caller_supplied_values) { + ECDSAerror(ECDSA_R_NEED_NEW_SETUP_VALUES); + goto err; + } + + if (++attempts > ECDSA_MAX_SIGN_ITERATIONS) { + ECDSAerror(EC_R_WRONG_CURVE_PARAMETERS); + goto err; + } + } while (1); + + /* Step 12: output (r, s). */ + if ((sig = ECDSA_SIG_new()) == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + if (!ECDSA_SIG_set0(sig, r, s)) { + ECDSA_SIG_free(sig); + goto err; + } + r = NULL; + s = NULL; + + err: + BN_CTX_end(ctx); + BN_CTX_free(ctx); + BN_free(kinv); + BN_free(r); + BN_free(s); + + return sig; +} + +int +ecdsa_verify(int type, const unsigned char *digest, int digest_len, + const unsigned char *sigbuf, int sig_len, EC_KEY *key) +{ + ECDSA_SIG *s; + unsigned char *der = NULL; + const unsigned char *p; + int der_len = 0; + int ret = -1; + + if ((s = ECDSA_SIG_new()) == NULL) + goto err; + + p = sigbuf; + if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL) + goto err; + + /* Ensure signature uses DER and doesn't have trailing garbage */ + if ((der_len = i2d_ECDSA_SIG(s, &der)) != sig_len) + goto err; + if (timingsafe_memcmp(sigbuf, der, der_len)) + goto err; + + ret = ECDSA_do_verify(digest, digest_len, s, key); + + err: + freezero(der, der_len); + ECDSA_SIG_free(s); + + return ret; +} + +/* + * FIPS 186-5, section 6.4.2: ECDSA signature verification. + * The caller provides us with the hash of the message, so has performed step 2. + */ + +int +ecdsa_verify_sig(const unsigned char *digest, int digest_len, + const ECDSA_SIG *sig, EC_KEY *key) +{ + const EC_GROUP *group; + const EC_POINT *pub_key; + EC_POINT *point = NULL; + const BIGNUM *order; + BN_CTX *ctx = NULL; + BIGNUM *e, *sinv, *u, *v, *x; + int ret = -1; + + if (key == NULL || sig == NULL) { + ECDSAerror(ECDSA_R_MISSING_PARAMETERS); + goto err; + } + if ((group = EC_KEY_get0_group(key)) == NULL) { + ECDSAerror(ECDSA_R_MISSING_PARAMETERS); + goto err; + } + if ((pub_key = EC_KEY_get0_public_key(key)) == NULL) { + ECDSAerror(ECDSA_R_MISSING_PARAMETERS); + goto err; + } + + if ((ctx = BN_CTX_new()) == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + + BN_CTX_start(ctx); + + if ((e = BN_CTX_get(ctx)) == NULL) + goto err; + if ((sinv = BN_CTX_get(ctx)) == NULL) + goto err; + if ((u = BN_CTX_get(ctx)) == NULL) + goto err; + if ((v = BN_CTX_get(ctx)) == NULL) + goto err; + if ((x = BN_CTX_get(ctx)) == NULL) + goto err; + + if ((order = EC_GROUP_get0_order(group)) == NULL) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + + /* Step 1: verify that r and s are in the range [1, order). */ + if (BN_cmp(sig->r, BN_value_one()) < 0 || BN_cmp(sig->r, order) >= 0) { + ECDSAerror(ECDSA_R_BAD_SIGNATURE); + ret = 0; + goto err; + } + if (BN_cmp(sig->s, BN_value_one()) < 0 || BN_cmp(sig->s, order) >= 0) { + ECDSAerror(ECDSA_R_BAD_SIGNATURE); + ret = 0; + goto err; + } + + /* Step 3: convert the hash into an integer. */ + if (!ecdsa_prepare_digest(digest, digest_len, key, e)) + goto err; + + /* Step 4: compute the inverse of s modulo order. */ + if (BN_mod_inverse_ct(sinv, sig->s, order, ctx) == NULL) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + /* Step 5: compute u = s^-1 * e and v = s^-1 * r (modulo order). */ + if (!BN_mod_mul(u, e, sinv, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + if (!BN_mod_mul(v, sig->r, sinv, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + + /* + * Steps 6 and 7: compute R = G * u + pub_key * v = (x, y). Reject if + * it's the point at infinity - getting affine coordinates fails. Keep + * the x coordinate. + */ + if ((point = EC_POINT_new(group)) == NULL) { + ECDSAerror(ERR_R_MALLOC_FAILURE); + goto err; + } + if (!EC_POINT_mul(group, point, u, pub_key, v, ctx)) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + if (!EC_POINT_get_affine_coordinates(group, point, x, NULL, ctx)) { + ECDSAerror(ERR_R_EC_LIB); + goto err; + } + /* Step 8: convert x to a number in [0, order). */ + if (!BN_nnmod(x, x, order, ctx)) { + ECDSAerror(ERR_R_BN_LIB); + goto err; + } + + /* Step 9: the signature is valid iff the x-coordinate is equal to r. */ + ret = (BN_cmp(x, sig->r) == 0); + + err: + BN_CTX_end(ctx); + BN_CTX_free(ctx); + EC_POINT_free(point); + + return ret; +} + +ECDSA_SIG * +ECDSA_do_sign(const unsigned char *digest, int digest_len, EC_KEY *key) +{ + return ECDSA_do_sign_ex(digest, digest_len, NULL, NULL, key); +} + +ECDSA_SIG * +ECDSA_do_sign_ex(const unsigned char *digest, int digest_len, + const BIGNUM *kinv, const BIGNUM *out_r, EC_KEY *key) +{ + if (key->meth->sign_sig == NULL) { + ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); + return 0; + } + return key->meth->sign_sig(digest, digest_len, kinv, out_r, key); +} + +int +ECDSA_sign(int type, const unsigned char *digest, int digest_len, + unsigned char *signature, unsigned int *signature_len, EC_KEY *key) +{ + return ECDSA_sign_ex(type, digest, digest_len, signature, signature_len, + NULL, NULL, key); +} + +int +ECDSA_sign_ex(int type, const unsigned char *digest, int digest_len, + unsigned char *signature, unsigned int *signature_len, const BIGNUM *kinv, + const BIGNUM *r, EC_KEY *key) +{ + if (key->meth->sign == NULL) { + ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); + return 0; + } + return key->meth->sign(type, digest, digest_len, signature, + signature_len, kinv, r, key); +} + +int +ECDSA_sign_setup(EC_KEY *key, BN_CTX *in_ctx, BIGNUM **out_kinv, + BIGNUM **out_r) +{ + if (key->meth->sign_setup == NULL) { + ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); + return 0; + } + return key->meth->sign_setup(key, in_ctx, out_kinv, out_r); +} + +int +ECDSA_do_verify(const unsigned char *digest, int digest_len, + const ECDSA_SIG *sig, EC_KEY *key) +{ + if (key->meth->verify_sig == NULL) { + ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); + return 0; + } + return key->meth->verify_sig(digest, digest_len, sig, key); +} + +int +ECDSA_verify(int type, const unsigned char *digest, int digest_len, + const unsigned char *sigbuf, int sig_len, EC_KEY *key) +{ + if (key->meth->verify == NULL) { + ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); + return 0; + } + return key->meth->verify(type, digest, digest_len, sigbuf, sig_len, key); +} + +int +ECDSA_size(const EC_KEY *r) +{ + const EC_GROUP *group; + const BIGNUM *order = NULL; + ECDSA_SIG sig; + int ret = 0; + + if (r == NULL) + goto err; + + if ((group = EC_KEY_get0_group(r)) == NULL) + goto err; + + if ((order = EC_GROUP_get0_order(group)) == NULL) + goto err; + + sig.r = (BIGNUM *)order; + sig.s = (BIGNUM *)order; + + if ((ret = i2d_ECDSA_SIG(&sig, NULL)) < 0) + ret = 0; + + err: + return ret; +} diff --git a/lib/libcrypto/ecdsa/ecs_asn1.c b/lib/libcrypto/ecdsa/ecs_asn1.c deleted file mode 100644 index 9e3506cd51d..00000000000 --- a/lib/libcrypto/ecdsa/ecs_asn1.c +++ /dev/null @@ -1,151 +0,0 @@ -/* $OpenBSD: ecs_asn1.c,v 1.15 2023/07/05 11:37:46 tb Exp $ */ -/* ==================================================================== - * Copyright (c) 2000-2002 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 - * licensing@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 -#include -#include - -#include "ecdsa_local.h" - -static const ASN1_TEMPLATE ECDSA_SIG_seq_tt[] = { - { - .flags = 0, - .tag = 0, - .offset = offsetof(ECDSA_SIG, r), - .field_name = "r", - .item = &BIGNUM_it, - }, - { - .flags = 0, - .tag = 0, - .offset = offsetof(ECDSA_SIG, s), - .field_name = "s", - .item = &BIGNUM_it, - }, -}; - -const ASN1_ITEM ECDSA_SIG_it = { - .itype = ASN1_ITYPE_SEQUENCE, - .utype = V_ASN1_SEQUENCE, - .templates = ECDSA_SIG_seq_tt, - .tcount = sizeof(ECDSA_SIG_seq_tt) / sizeof(ASN1_TEMPLATE), - .funcs = NULL, - .size = sizeof(ECDSA_SIG), - .sname = "ECDSA_SIG", -}; - -ECDSA_SIG *ECDSA_SIG_new(void); -void ECDSA_SIG_free(ECDSA_SIG *a); -ECDSA_SIG *d2i_ECDSA_SIG(ECDSA_SIG **a, const unsigned char **in, long len); -int i2d_ECDSA_SIG(const ECDSA_SIG *a, unsigned char **out); - -ECDSA_SIG * -d2i_ECDSA_SIG(ECDSA_SIG **a, const unsigned char **in, long len) -{ - return (ECDSA_SIG *)ASN1_item_d2i((ASN1_VALUE **)a, in, len, - &ECDSA_SIG_it); -} - -int -i2d_ECDSA_SIG(const ECDSA_SIG *a, unsigned char **out) -{ - return ASN1_item_i2d((ASN1_VALUE *)a, out, &ECDSA_SIG_it); -} - -ECDSA_SIG * -ECDSA_SIG_new(void) -{ - return (ECDSA_SIG *)ASN1_item_new(&ECDSA_SIG_it); -} - -void -ECDSA_SIG_free(ECDSA_SIG *a) -{ - ASN1_item_free((ASN1_VALUE *)a, &ECDSA_SIG_it); -} - -void -ECDSA_SIG_get0(const ECDSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps) -{ - if (pr != NULL) - *pr = sig->r; - if (ps != NULL) - *ps = sig->s; -} - -const BIGNUM * -ECDSA_SIG_get0_r(const ECDSA_SIG *sig) -{ - return sig->r; -} - -const BIGNUM * -ECDSA_SIG_get0_s(const ECDSA_SIG *sig) -{ - return sig->s; -} - -int -ECDSA_SIG_set0(ECDSA_SIG *sig, BIGNUM *r, BIGNUM *s) -{ - if (r == NULL || s == NULL) - return 0; - - BN_free(sig->r); - BN_free(sig->s); - sig->r = r; - sig->s = s; - return 1; -} diff --git a/lib/libcrypto/ecdsa/ecs_ossl.c b/lib/libcrypto/ecdsa/ecs_ossl.c deleted file mode 100644 index 9886852e0f9..00000000000 --- a/lib/libcrypto/ecdsa/ecs_ossl.c +++ /dev/null @@ -1,732 +0,0 @@ -/* $OpenBSD: ecs_ossl.c,v 1.73 2023/07/05 11:37:46 tb Exp $ */ -/* - * 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 - -#include - -#include -#include -#include -#include - -#include "bn_local.h" -#include "ec_local.h" -#include "ecdsa_local.h" - -/* - * FIPS 186-5, section 6.4.1, step 2: convert hashed message into an integer. - * Use the order_bits leftmost bits if it exceeds the group order. - */ -static int -ecdsa_prepare_digest(const unsigned char *digest, int digest_len, - const EC_KEY *key, BIGNUM *e) -{ - const EC_GROUP *group; - int digest_bits, order_bits; - - if (!BN_bin2bn(digest, digest_len, e)) { - ECDSAerror(ERR_R_BN_LIB); - return 0; - } - - if ((group = EC_KEY_get0_group(key)) == NULL) - return 0; - order_bits = EC_GROUP_order_bits(group); - - digest_bits = 8 * digest_len; - if (digest_bits <= order_bits) - return 1; - - return BN_rshift(e, e, digest_bits - order_bits); -} - -int -ecdsa_sign(int type, const unsigned char *digest, int digest_len, - unsigned char *signature, unsigned int *signature_len, const BIGNUM *kinv, - const BIGNUM *r, EC_KEY *key) -{ - ECDSA_SIG *sig; - int out_len = 0; - int ret = 0; - - if ((sig = ECDSA_do_sign_ex(digest, digest_len, kinv, r, key)) == NULL) - goto err; - - if ((out_len = i2d_ECDSA_SIG(sig, &signature)) < 0) { - out_len = 0; - goto err; - } - - ret = 1; - - err: - *signature_len = out_len; - ECDSA_SIG_free(sig); - - return ret; -} - -/* - * FIPS 186-5, section 6.4.1, steps 3-8 and 11: Generate k, calculate r and - * kinv, and clear it. If r == 0, try again with a new random k. - */ - -int -ecdsa_sign_setup(EC_KEY *key, BN_CTX *in_ctx, BIGNUM **out_kinv, BIGNUM **out_r) -{ - const EC_GROUP *group; - EC_POINT *point = NULL; - BN_CTX *ctx = NULL; - BIGNUM *k = NULL, *r = NULL; - const BIGNUM *order; - BIGNUM *x; - int order_bits; - int ret = 0; - - BN_free(*out_kinv); - *out_kinv = NULL; - - BN_free(*out_r); - *out_r = NULL; - - if (key == NULL) { - ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); - goto err; - } - if ((group = EC_KEY_get0_group(key)) == NULL) { - ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); - goto err; - } - - if ((k = BN_new()) == NULL) - goto err; - if ((r = BN_new()) == NULL) - goto err; - - if ((ctx = in_ctx) == NULL) - ctx = BN_CTX_new(); - if (ctx == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - - BN_CTX_start(ctx); - - if ((x = BN_CTX_get(ctx)) == NULL) - goto err; - - if ((point = EC_POINT_new(group)) == NULL) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - if ((order = EC_GROUP_get0_order(group)) == NULL) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - - if (BN_cmp(order, BN_value_one()) <= 0) { - ECDSAerror(EC_R_INVALID_GROUP_ORDER); - goto err; - } - - /* Reject curves with an order that is smaller than 80 bits. */ - if ((order_bits = BN_num_bits(order)) < 80) { - ECDSAerror(EC_R_INVALID_GROUP_ORDER); - goto err; - } - - /* Preallocate space. */ - if (!BN_set_bit(k, order_bits) || - !BN_set_bit(r, order_bits) || - !BN_set_bit(x, order_bits)) - goto err; - - /* Step 11: repeat until r != 0. */ - do { - /* Step 3: generate random k. */ - if (!bn_rand_interval(k, BN_value_one(), order)) { - ECDSAerror(ECDSA_R_RANDOM_NUMBER_GENERATION_FAILED); - goto err; - } - - /* - * 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 unconditionally perform both of these additions to prevent - * a small timing information leakage. We then choose the sum - * that is one bit longer than the order. This guarantees the - * code path used in the constant time implementations - * elsewhere. - * - * TODO: revisit the bn_copy aiming for a memory access agnostic - * conditional copy. - */ - if (!BN_add(r, k, order) || - !BN_add(x, r, order) || - !bn_copy(k, BN_num_bits(r) > order_bits ? r : x)) - goto err; - - BN_set_flags(k, BN_FLG_CONSTTIME); - - /* Step 5: P = k * G. */ - if (!EC_POINT_mul(group, point, k, NULL, NULL, ctx)) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - /* Steps 6 (and 7): from P = (x, y) retain the x-coordinate. */ - if (!EC_POINT_get_affine_coordinates(group, point, x, NULL, - ctx)) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - /* Step 8: r = x (mod order). */ - if (!BN_nnmod(r, x, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - } while (BN_is_zero(r)); - - /* Step 4: calculate kinv. */ - if (BN_mod_inverse_ct(k, k, order, ctx) == NULL) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - - *out_kinv = k; - k = NULL; - - *out_r = r; - r = NULL; - - ret = 1; - - err: - BN_CTX_end(ctx); - if (ctx != in_ctx) - BN_CTX_free(ctx); - BN_free(k); - BN_free(r); - EC_POINT_free(point); - - return ret; -} - -/* - * FIPS 186-5, section 6.4.1, step 9: compute s = inv(k)(e + xr) mod order. - * In order to reduce the possibility of a side-channel attack, the following - * is calculated using a random blinding value b in [1, order): - * s = inv(b)(be + bxr)inv(k) mod order. - */ - -static int -ecdsa_compute_s(BIGNUM **out_s, const BIGNUM *e, const BIGNUM *kinv, - const BIGNUM *r, const EC_KEY *key, BN_CTX *ctx) -{ - const EC_GROUP *group; - const BIGNUM *order, *priv_key; - BIGNUM *b, *binv, *be, *bxr; - BIGNUM *s = NULL; - int ret = 0; - - *out_s = NULL; - - BN_CTX_start(ctx); - - if ((group = EC_KEY_get0_group(key)) == NULL) { - ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); - goto err; - } - if ((order = EC_GROUP_get0_order(group)) == NULL) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - if ((priv_key = EC_KEY_get0_private_key(key)) == NULL) { - ECDSAerror(ERR_R_PASSED_NULL_PARAMETER); - goto err; - } - - if ((b = BN_CTX_get(ctx)) == NULL) - goto err; - if ((binv = BN_CTX_get(ctx)) == NULL) - goto err; - if ((be = BN_CTX_get(ctx)) == NULL) - goto err; - if ((bxr = BN_CTX_get(ctx)) == NULL) - goto err; - - if ((s = BN_new()) == NULL) - goto err; - - /* - * In a valid ECDSA signature, r must be in [1, order). Since r can be - * caller provided - either directly or by replacing sign_setup() - we - * can't rely on this being the case. - */ - if (BN_cmp(r, BN_value_one()) < 0 || BN_cmp(r, order) >= 0) { - ECDSAerror(ECDSA_R_BAD_SIGNATURE); - goto err; - } - - if (!bn_rand_interval(b, BN_value_one(), order)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - - if (BN_mod_inverse_ct(binv, b, order, ctx) == NULL) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - - if (!BN_mod_mul(bxr, b, priv_key, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_mul(bxr, bxr, r, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_mul(be, b, e, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_add(s, be, bxr, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - /* s = b(e + xr)k^-1 */ - if (!BN_mod_mul(s, s, kinv, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - /* s = (e + xr)k^-1 */ - if (!BN_mod_mul(s, s, binv, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - - /* Step 11: if s == 0 start over. */ - if (!BN_is_zero(s)) { - *out_s = s; - s = NULL; - } - - ret = 1; - - err: - BN_CTX_end(ctx); - BN_free(s); - - return ret; -} - -/* - * It is too expensive to check curve parameters on every sign operation. - * Instead, cap the number of retries. A single retry is very unlikely, so - * allowing 32 retries is amply enough. - */ -#define ECDSA_MAX_SIGN_ITERATIONS 32 - -/* - * FIPS 186-5: Section 6.4.1: ECDSA signature generation, steps 2-12. - * The caller provides the hash of the message, thus performs step 1. - * Step 10, zeroing k and kinv, is done by BN_free(). - */ - -ECDSA_SIG * -ecdsa_sign_sig(const unsigned char *digest, int digest_len, - const BIGNUM *in_kinv, const BIGNUM *in_r, EC_KEY *key) -{ - BN_CTX *ctx = NULL; - BIGNUM *kinv = NULL, *r = NULL, *s = NULL; - BIGNUM *e; - int caller_supplied_values = 0; - int attempts = 0; - ECDSA_SIG *sig = NULL; - - if ((ctx = BN_CTX_new()) == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - - BN_CTX_start(ctx); - - if ((e = BN_CTX_get(ctx)) == NULL) - goto err; - - /* Step 2: convert hash into an integer. */ - if (!ecdsa_prepare_digest(digest, digest_len, key, e)) - goto err; - - if (in_kinv != NULL && in_r != NULL) { - /* - * Use the caller's kinv and r. Don't call ECDSA_sign_setup(). - * If we're unable to compute a valid signature, the caller - * must provide new values. - */ - caller_supplied_values = 1; - - if ((kinv = BN_dup(in_kinv)) == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - if ((r = BN_dup(in_r)) == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - } - - do { - /* Steps 3-8: calculate kinv and r. */ - if (!caller_supplied_values) { - if (!ECDSA_sign_setup(key, ctx, &kinv, &r)) { - ECDSAerror(ERR_R_ECDSA_LIB); - goto err; - } - } - - /* - * Steps 9 and 11: if s is non-NULL, we have a valid signature. - */ - if (!ecdsa_compute_s(&s, e, kinv, r, key, ctx)) - goto err; - if (s != NULL) - break; - - if (caller_supplied_values) { - ECDSAerror(ECDSA_R_NEED_NEW_SETUP_VALUES); - goto err; - } - - if (++attempts > ECDSA_MAX_SIGN_ITERATIONS) { - ECDSAerror(EC_R_WRONG_CURVE_PARAMETERS); - goto err; - } - } while (1); - - /* Step 12: output (r, s). */ - if ((sig = ECDSA_SIG_new()) == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - if (!ECDSA_SIG_set0(sig, r, s)) { - ECDSA_SIG_free(sig); - goto err; - } - r = NULL; - s = NULL; - - err: - BN_CTX_end(ctx); - BN_CTX_free(ctx); - BN_free(kinv); - BN_free(r); - BN_free(s); - - return sig; -} - -int -ecdsa_verify(int type, const unsigned char *digest, int digest_len, - const unsigned char *sigbuf, int sig_len, EC_KEY *key) -{ - ECDSA_SIG *s; - unsigned char *der = NULL; - const unsigned char *p; - int der_len = 0; - int ret = -1; - - if ((s = ECDSA_SIG_new()) == NULL) - goto err; - - p = sigbuf; - if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL) - goto err; - - /* Ensure signature uses DER and doesn't have trailing garbage */ - if ((der_len = i2d_ECDSA_SIG(s, &der)) != sig_len) - goto err; - if (timingsafe_memcmp(sigbuf, der, der_len)) - goto err; - - ret = ECDSA_do_verify(digest, digest_len, s, key); - - err: - freezero(der, der_len); - ECDSA_SIG_free(s); - - return ret; -} - -/* - * FIPS 186-5, section 6.4.2: ECDSA signature verification. - * The caller provides us with the hash of the message, so has performed step 2. - */ - -int -ecdsa_verify_sig(const unsigned char *digest, int digest_len, - const ECDSA_SIG *sig, EC_KEY *key) -{ - const EC_GROUP *group; - const EC_POINT *pub_key; - EC_POINT *point = NULL; - const BIGNUM *order; - BN_CTX *ctx = NULL; - BIGNUM *e, *sinv, *u, *v, *x; - int ret = -1; - - if (key == NULL || sig == NULL) { - ECDSAerror(ECDSA_R_MISSING_PARAMETERS); - goto err; - } - if ((group = EC_KEY_get0_group(key)) == NULL) { - ECDSAerror(ECDSA_R_MISSING_PARAMETERS); - goto err; - } - if ((pub_key = EC_KEY_get0_public_key(key)) == NULL) { - ECDSAerror(ECDSA_R_MISSING_PARAMETERS); - goto err; - } - - if ((ctx = BN_CTX_new()) == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - - BN_CTX_start(ctx); - - if ((e = BN_CTX_get(ctx)) == NULL) - goto err; - if ((sinv = BN_CTX_get(ctx)) == NULL) - goto err; - if ((u = BN_CTX_get(ctx)) == NULL) - goto err; - if ((v = BN_CTX_get(ctx)) == NULL) - goto err; - if ((x = BN_CTX_get(ctx)) == NULL) - goto err; - - if ((order = EC_GROUP_get0_order(group)) == NULL) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - - /* Step 1: verify that r and s are in the range [1, order). */ - if (BN_cmp(sig->r, BN_value_one()) < 0 || BN_cmp(sig->r, order) >= 0) { - ECDSAerror(ECDSA_R_BAD_SIGNATURE); - ret = 0; - goto err; - } - if (BN_cmp(sig->s, BN_value_one()) < 0 || BN_cmp(sig->s, order) >= 0) { - ECDSAerror(ECDSA_R_BAD_SIGNATURE); - ret = 0; - goto err; - } - - /* Step 3: convert the hash into an integer. */ - if (!ecdsa_prepare_digest(digest, digest_len, key, e)) - goto err; - - /* Step 4: compute the inverse of s modulo order. */ - if (BN_mod_inverse_ct(sinv, sig->s, order, ctx) == NULL) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - /* Step 5: compute u = s^-1 * e and v = s^-1 * r (modulo order). */ - if (!BN_mod_mul(u, e, sinv, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - if (!BN_mod_mul(v, sig->r, sinv, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - - /* - * Steps 6 and 7: compute R = G * u + pub_key * v = (x, y). Reject if - * it's the point at infinity - getting affine coordinates fails. Keep - * the x coordinate. - */ - if ((point = EC_POINT_new(group)) == NULL) { - ECDSAerror(ERR_R_MALLOC_FAILURE); - goto err; - } - if (!EC_POINT_mul(group, point, u, pub_key, v, ctx)) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - if (!EC_POINT_get_affine_coordinates(group, point, x, NULL, ctx)) { - ECDSAerror(ERR_R_EC_LIB); - goto err; - } - /* Step 8: convert x to a number in [0, order). */ - if (!BN_nnmod(x, x, order, ctx)) { - ECDSAerror(ERR_R_BN_LIB); - goto err; - } - - /* Step 9: the signature is valid iff the x-coordinate is equal to r. */ - ret = (BN_cmp(x, sig->r) == 0); - - err: - BN_CTX_end(ctx); - BN_CTX_free(ctx); - EC_POINT_free(point); - - return ret; -} - -ECDSA_SIG * -ECDSA_do_sign(const unsigned char *digest, int digest_len, EC_KEY *key) -{ - return ECDSA_do_sign_ex(digest, digest_len, NULL, NULL, key); -} - -ECDSA_SIG * -ECDSA_do_sign_ex(const unsigned char *digest, int digest_len, - const BIGNUM *kinv, const BIGNUM *out_r, EC_KEY *key) -{ - if (key->meth->sign_sig == NULL) { - ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); - return 0; - } - return key->meth->sign_sig(digest, digest_len, kinv, out_r, key); -} - -int -ECDSA_sign(int type, const unsigned char *digest, int digest_len, - unsigned char *signature, unsigned int *signature_len, EC_KEY *key) -{ - return ECDSA_sign_ex(type, digest, digest_len, signature, signature_len, - NULL, NULL, key); -} - -int -ECDSA_sign_ex(int type, const unsigned char *digest, int digest_len, - unsigned char *signature, unsigned int *signature_len, const BIGNUM *kinv, - const BIGNUM *r, EC_KEY *key) -{ - if (key->meth->sign == NULL) { - ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); - return 0; - } - return key->meth->sign(type, digest, digest_len, signature, - signature_len, kinv, r, key); -} - -int -ECDSA_sign_setup(EC_KEY *key, BN_CTX *in_ctx, BIGNUM **out_kinv, - BIGNUM **out_r) -{ - if (key->meth->sign_setup == NULL) { - ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); - return 0; - } - return key->meth->sign_setup(key, in_ctx, out_kinv, out_r); -} - -int -ECDSA_do_verify(const unsigned char *digest, int digest_len, - const ECDSA_SIG *sig, EC_KEY *key) -{ - if (key->meth->verify_sig == NULL) { - ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); - return 0; - } - return key->meth->verify_sig(digest, digest_len, sig, key); -} - -int -ECDSA_verify(int type, const unsigned char *digest, int digest_len, - const unsigned char *sigbuf, int sig_len, EC_KEY *key) -{ - if (key->meth->verify == NULL) { - ECDSAerror(EVP_R_METHOD_NOT_SUPPORTED); - return 0; - } - return key->meth->verify(type, digest, digest_len, sigbuf, sig_len, key); -} - -int -ECDSA_size(const EC_KEY *r) -{ - const EC_GROUP *group; - const BIGNUM *order = NULL; - ECDSA_SIG sig; - int ret = 0; - - if (r == NULL) - goto err; - - if ((group = EC_KEY_get0_group(r)) == NULL) - goto err; - - if ((order = EC_GROUP_get0_order(group)) == NULL) - goto err; - - sig.r = (BIGNUM *)order; - sig.s = (BIGNUM *)order; - - if ((ret = i2d_ECDSA_SIG(&sig, NULL)) < 0) - ret = 0; - - err: - return ret; -}