/src/openssl30/crypto/ec/ecdsa_ossl.c

Source (jump to first uncovered line)
/*
 * Copyright 2002-2023 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

/*
 * ECDSA low level APIs are deprecated for public use, but still ok for
 * internal use.
 */
#include "internal/deprecated.h"

#include <string.h>
#include <openssl/err.h>
#include <openssl/obj_mac.h>
#include <openssl/rand.h>
#include "crypto/bn.h"
#include "ec_local.h"

#define MIN_ECDSA_SIGN_ORDERBITS 64
/*
 * It is highly unlikely that a retry will happen,
 * Multiple retries would indicate that something is wrong
 * with the group parameters (which would normally only happen
 * with a bad custom group).
 */
#define MAX_ECDSA_SIGN_RETRIES 8

int ossl_ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
                          BIGNUM **rp)
{
    if (eckey->group->meth->ecdsa_sign_setup == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
        return 0;
    }

    return eckey->group->meth->ecdsa_sign_setup(eckey, ctx_in, kinvp, rp);
}

ECDSA_SIG *ossl_ecdsa_sign_sig(const unsigned char *dgst, int dgst_len,
                               const BIGNUM *in_kinv, const BIGNUM *in_r,
                               EC_KEY *eckey)
{
    if (eckey->group->meth->ecdsa_sign_sig == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
        return NULL;
    }

    return eckey->group->meth->ecdsa_sign_sig(dgst, dgst_len,
                                              in_kinv, in_r, eckey);
}

int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
                          const ECDSA_SIG *sig, EC_KEY *eckey)
{
    if (eckey->group->meth->ecdsa_verify_sig == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
        return 0;
    }

    return eckey->group->meth->ecdsa_verify_sig(dgst, dgst_len, sig, eckey);
}

int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen,
                    unsigned char *sig, unsigned int *siglen,
                    const BIGNUM *kinv, const BIGNUM *r, EC_KEY *eckey)
{
    ECDSA_SIG *s;

    s = ECDSA_do_sign_ex(dgst, dlen, kinv, r, eckey);
    if (s == NULL) {
        *siglen = 0;
        return 0;
    }
    *siglen = i2d_ECDSA_SIG(s, sig != NULL ? &sig : NULL);
    ECDSA_SIG_free(s);
    return 1;
}

static int ecdsa_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in,
                            BIGNUM **kinvp, BIGNUM **rp,
                            const unsigned char *dgst, int dlen)
{
    BN_CTX *ctx = NULL;
    BIGNUM *k = NULL, *r = NULL, *X = NULL;
    const BIGNUM *order;
    EC_POINT *tmp_point = NULL;
    const EC_GROUP *group;
    int ret = 0;
    int order_bits;
    const BIGNUM *priv_key;

    if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    if ((priv_key = EC_KEY_get0_private_key(eckey)) == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_MISSING_PRIVATE_KEY);
        return 0;
    }

    if (!EC_KEY_can_sign(eckey)) {
        ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
        return 0;
    }

    if ((ctx = ctx_in) == NULL) {
        if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL) {
            ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
            return 0;
        }
    }

    k = BN_secure_new();        /* this value is later returned in *kinvp */
    r = BN_new();               /* this value is later returned in *rp */
    X = BN_new();
    if (k == NULL || r == NULL || X == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    if ((tmp_point = EC_POINT_new(group)) == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
        goto err;
    }
    order = EC_GROUP_get0_order(group);

    /* Preallocate space */
    order_bits = BN_num_bits(order);
    /* Check the number of bits here so that an infinite loop is not possible */
    if (order_bits < MIN_ECDSA_SIGN_ORDERBITS
        || !BN_set_bit(k, order_bits)
        || !BN_set_bit(r, order_bits)
        || !BN_set_bit(X, order_bits))
        goto err;

    do {
        /* get random k */
        do {
            if (dgst != NULL) {
                if (!BN_generate_dsa_nonce(k, order, priv_key,
                                           dgst, dlen, ctx)) {
                    ERR_raise(ERR_LIB_EC, EC_R_RANDOM_NUMBER_GENERATION_FAILED);
                    goto err;
                }
            } else {
                if (!BN_priv_rand_range_ex(k, order, 0, ctx)) {
                    ERR_raise(ERR_LIB_EC, EC_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)) {
            ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
            goto err;
        }

        if (!EC_POINT_get_affine_coordinates(group, tmp_point, X, NULL, ctx)) {
            ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
            goto err;
        }

        if (!BN_nnmod(r, X, order, ctx)) {
            ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
            goto err;
        }
    } while (BN_is_zero(r));

    /* compute the inverse of k */
    if (!ossl_ec_group_do_inverse_ord(group, k, k, ctx)) {
        ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        goto err;
    }

    /* clear old values if necessary */
    BN_clear_free(*rp);
    BN_clear_free(*kinvp);
    /* save the pre-computed values  */
    *rp = r;
    *kinvp = k;
    ret = 1;
 err:
    if (!ret) {
        BN_clear_free(k);
        BN_clear_free(r);
    }
    if (ctx != ctx_in)
        BN_CTX_free(ctx);
    EC_POINT_free(tmp_point);
    BN_clear_free(X);
    return ret;
}

int ossl_ecdsa_simple_sign_setup(EC_KEY *eckey, BN_CTX *ctx_in, BIGNUM **kinvp,
                                 BIGNUM **rp)
{
    return ecdsa_sign_setup(eckey, ctx_in, kinvp, rp, NULL, 0);
}

ECDSA_SIG *ossl_ecdsa_simple_sign_sig(const unsigned char *dgst, int dgst_len,
                                      const BIGNUM *in_kinv, const BIGNUM *in_r,
                                      EC_KEY *eckey)
{
    int ok = 0, i;
    int retries = 0;
    BIGNUM *kinv = NULL, *s, *m = NULL;
    const BIGNUM *order, *ckinv;
    BN_CTX *ctx = NULL;
    const EC_GROUP *group;
    ECDSA_SIG *ret;
    const BIGNUM *priv_key;

    group = EC_KEY_get0_group(eckey);
    priv_key = EC_KEY_get0_private_key(eckey);

    if (group == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
        return NULL;
    }
    if (priv_key == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_MISSING_PRIVATE_KEY);
        return NULL;
    }

    if (!EC_KEY_can_sign(eckey)) {
        ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
        return NULL;
    }

    ret = ECDSA_SIG_new();
    if (ret == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        return NULL;
    }
    ret->r = BN_new();
    ret->s = BN_new();
    if (ret->r == NULL || ret->s == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    s = ret->s;

    if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL
        || (m = BN_new()) == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        goto err;
    }

    order = EC_GROUP_get0_order(group);
    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)) {
        ERR_raise(ERR_LIB_EC, 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))) {
        ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        goto err;
    }
    do {
        if (in_kinv == NULL || in_r == NULL) {
            if (!ecdsa_sign_setup(eckey, ctx, &kinv, &ret->r, dgst, dgst_len)) {
                ERR_raise(ERR_LIB_EC, ERR_R_ECDSA_LIB);
                goto err;
            }
            ckinv = kinv;
        } else {
            ckinv = in_kinv;
            if (BN_copy(ret->r, in_r) == NULL) {
                ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
                goto err;
            }
        }

        /*
         * With only one multiplicant being in Montgomery domain
         * multiplication yields real result without post-conversion.
         * Also note that all operations but last are performed with
         * zero-padded vectors. Last operation, BN_mod_mul_montgomery
         * below, returns user-visible value with removed zero padding.
         */
        if (!bn_to_mont_fixed_top(s, ret->r, group->mont_data, ctx)
            || !bn_mul_mont_fixed_top(s, s, priv_key, group->mont_data, ctx)) {
            ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
            goto err;
        }
        if (!bn_mod_add_fixed_top(s, s, m, order)) {
            ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
            goto err;
        }
        /*
         * |s| can still be larger than modulus, because |m| can be. In
         * such case we count on Montgomery reduction to tie it up.
         */
        if (!bn_to_mont_fixed_top(s, s, group->mont_data, ctx)
            || !BN_mod_mul_montgomery(s, s, ckinv, group->mont_data, ctx)) {
            ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
            goto err;
        }

        if (BN_is_zero(s)) {
            /*
             * if kinv and r have been supplied by the caller, don't
             * generate new kinv and r values
             */
            if (in_kinv != NULL && in_r != NULL) {
                ERR_raise(ERR_LIB_EC, EC_R_NEED_NEW_SETUP_VALUES);
                goto err;
            }
            /* Avoid infinite loops cause by invalid group parameters */
            if (retries++ > MAX_ECDSA_SIGN_RETRIES) {
                ERR_raise(ERR_LIB_EC, EC_R_TOO_MANY_RETRIES);
                goto err;
            }
        } else {
            /* s != 0 => we have a valid signature */
            break;
        }
    } while (1);

    ok = 1;
 err:
    if (!ok) {
        ECDSA_SIG_free(ret);
        ret = NULL;
    }
    BN_CTX_free(ctx);
    BN_clear_free(m);
    BN_clear_free(kinv);
    return ret;
}

/*-
 * returns
 *      1: correct signature
 *      0: incorrect signature
 *     -1: error
 */
int ossl_ecdsa_verify(int type, const unsigned char *dgst, int dgst_len,
                      const unsigned char *sigbuf, int sig_len, EC_KEY *eckey)
{
    ECDSA_SIG *s;
    const unsigned char *p = sigbuf;
    unsigned char *der = NULL;
    int derlen = -1;
    int ret = -1;

    s = ECDSA_SIG_new();
    if (s == NULL)
        return ret;
    if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL)
        goto err;
    /* Ensure signature uses DER and doesn't have trailing garbage */
    derlen = i2d_ECDSA_SIG(s, &der);
    if (derlen != sig_len || memcmp(sigbuf, der, derlen) != 0)
        goto err;
    ret = ECDSA_do_verify(dgst, dgst_len, s, eckey);
 err:
    OPENSSL_free(der);
    ECDSA_SIG_free(s);
    return ret;
}

int ossl_ecdsa_simple_verify_sig(const unsigned char *dgst, int dgst_len,
                                 const ECDSA_SIG *sig, EC_KEY *eckey)
{
    int ret = -1, i;
    BN_CTX *ctx;
    const BIGNUM *order;
    BIGNUM *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) {
        ERR_raise(ERR_LIB_EC, EC_R_MISSING_PARAMETERS);
        return -1;
    }

    if (!EC_KEY_can_sign(eckey)) {
        ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
        return -1;
    }

    ctx = BN_CTX_new_ex(eckey->libctx);
    if (ctx == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        return -1;
    }
    BN_CTX_start(ctx);
    u1 = BN_CTX_get(ctx);
    u2 = BN_CTX_get(ctx);
    m = BN_CTX_get(ctx);
    X = BN_CTX_get(ctx);
    if (X == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        goto err;
    }

    order = EC_GROUP_get0_order(group);
    if (order == NULL) {
        ERR_raise(ERR_LIB_EC, 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) {
        ERR_raise(ERR_LIB_EC, EC_R_BAD_SIGNATURE);
        ret = 0;                /* signature is invalid */
        goto err;
    }
    /* calculate tmp1 = inv(S) mod order */
    if (!ossl_ec_group_do_inverse_ord(group, u2, sig->s, ctx)) {
        ERR_raise(ERR_LIB_EC, 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)) {
        ERR_raise(ERR_LIB_EC, 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))) {
        ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        goto err;
    }
    /* u1 = m * tmp mod order */
    if (!BN_mod_mul(u1, m, u2, order, ctx)) {
        ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        goto err;
    }
    /* u2 = r * w mod q */
    if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {
        ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
        goto err;
    }

    if ((point = EC_POINT_new(group)) == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        goto err;
    }
    if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) {
        ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
        goto err;
    }

    if (!EC_POINT_get_affine_coordinates(group, point, X, NULL, ctx)) {
        ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
        goto err;
    }

    if (!BN_nnmod(u1, X, order, ctx)) {
        ERR_raise(ERR_LIB_EC, 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);
    EC_POINT_free(point);
    return ret;
}

Coverage Report

Created: 2023-06-08 06:41

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2002-2023 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the Apache License 2.0 (the "License"). You may not use
5		* this file except in compliance with the License. You can obtain a copy
6		* in the file LICENSE in the source distribution or at
7		* https://www.openssl.org/source/license.html
8		*/
9
10		/*
11		* ECDSA low level APIs are deprecated for public use, but still ok for
12		* internal use.
13		*/
14		#include "internal/deprecated.h"
15
16		#include <string.h>
17		#include <openssl/err.h>
18		#include <openssl/obj_mac.h>
19		#include <openssl/rand.h>
20		#include "crypto/bn.h"
21		#include "ec_local.h"
22
23	0	#define MIN_ECDSA_SIGN_ORDERBITS 64
24		/*
25		* It is highly unlikely that a retry will happen,
26		* Multiple retries would indicate that something is wrong
27		* with the group parameters (which would normally only happen
28		* with a bad custom group).
29		*/
30	0	#define MAX_ECDSA_SIGN_RETRIES 8
31
32		int ossl_ecdsa_sign_setup(EC_KEY eckey, BN_CTX ctx_in, BIGNUM **kinvp,
33		BIGNUM **rp)
34	0	{
35	0	if (eckey->group->meth->ecdsa_sign_setup == NULL) {
36	0	ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
37	0	return 0;
38	0	}
39
40	0	return eckey->group->meth->ecdsa_sign_setup(eckey, ctx_in, kinvp, rp);
41	0	}
42
43		ECDSA_SIG ossl_ecdsa_sign_sig(const unsigned char dgst, int dgst_len,
44		const BIGNUM in_kinv, const BIGNUM in_r,
45		EC_KEY *eckey)
46	0	{
47	0	if (eckey->group->meth->ecdsa_sign_sig == NULL) {
48	0	ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
49	0	return NULL;
50	0	}
51
52	0	return eckey->group->meth->ecdsa_sign_sig(dgst, dgst_len,
53	0	in_kinv, in_r, eckey);
54	0	}
55
56		int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
57		const ECDSA_SIG sig, EC_KEY eckey)
58	17	{
59	17	if (eckey->group->meth->ecdsa_verify_sig == NULL) {
60	0	ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_ECDSA);
61	0	return 0;
62	0	}
63
64	17	return eckey->group->meth->ecdsa_verify_sig(dgst, dgst_len, sig, eckey);
65	17	}
66
67		int ossl_ecdsa_sign(int type, const unsigned char *dgst, int dlen,
68		unsigned char sig, unsigned int siglen,
69		const BIGNUM kinv, const BIGNUM r, EC_KEY *eckey)
70	0	{
71	0	ECDSA_SIG *s;
72
73	0	s = ECDSA_do_sign_ex(dgst, dlen, kinv, r, eckey);
74	0	if (s == NULL) {
75	0	*siglen = 0;
76	0	return 0;
77	0	}
78	0	*siglen = i2d_ECDSA_SIG(s, sig != NULL ? &sig : NULL);
79	0	ECDSA_SIG_free(s);
80	0	return 1;
81	0	}
82
83		static int ecdsa_sign_setup(EC_KEY eckey, BN_CTX ctx_in,
84		BIGNUM kinvp, BIGNUM rp,
85		const unsigned char *dgst, int dlen)
86	0	{
87	0	BN_CTX *ctx = NULL;
88	0	BIGNUM k = NULL, r = NULL, *X = NULL;
89	0	const BIGNUM *order;
90	0	EC_POINT *tmp_point = NULL;
91	0	const EC_GROUP *group;
92	0	int ret = 0;
93	0	int order_bits;
94	0	const BIGNUM *priv_key;
95
96	0	if (eckey == NULL \|\| (group = EC_KEY_get0_group(eckey)) == NULL) {
97	0	ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
98	0	return 0;
99	0	}
100	0	if ((priv_key = EC_KEY_get0_private_key(eckey)) == NULL) {
101	0	ERR_raise(ERR_LIB_EC, EC_R_MISSING_PRIVATE_KEY);
102	0	return 0;
103	0	}
104
105	0	if (!EC_KEY_can_sign(eckey)) {
106	0	ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
107	0	return 0;
108	0	}
109
110	0	if ((ctx = ctx_in) == NULL) {
111	0	if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL) {
112	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
113	0	return 0;
114	0	}
115	0	}
116
117	0	k = BN_secure_new(); /* this value is later returned in kinvp /
118	0	r = BN_new(); /* this value is later returned in rp /
119	0	X = BN_new();
120	0	if (k == NULL \|\| r == NULL \|\| X == NULL) {
121	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
122	0	goto err;
123	0	}
124	0	if ((tmp_point = EC_POINT_new(group)) == NULL) {
125	0	ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
126	0	goto err;
127	0	}
128	0	order = EC_GROUP_get0_order(group);
129
130		/* Preallocate space */
131	0	order_bits = BN_num_bits(order);
132		/* Check the number of bits here so that an infinite loop is not possible */
133	0	if (order_bits < MIN_ECDSA_SIGN_ORDERBITS
134	0	\|\| !BN_set_bit(k, order_bits)
135	0	\|\| !BN_set_bit(r, order_bits)
136	0	\|\| !BN_set_bit(X, order_bits))
137	0	goto err;
138
139	0	do {
140		/* get random k */
141	0	do {
142	0	if (dgst != NULL) {
143	0	if (!BN_generate_dsa_nonce(k, order, priv_key,
144	0	dgst, dlen, ctx)) {
145	0	ERR_raise(ERR_LIB_EC, EC_R_RANDOM_NUMBER_GENERATION_FAILED);
146	0	goto err;
147	0	}
148	0	} else {
149	0	if (!BN_priv_rand_range_ex(k, order, 0, ctx)) {
150	0	ERR_raise(ERR_LIB_EC, EC_R_RANDOM_NUMBER_GENERATION_FAILED);
151	0	goto err;
152	0	}
153	0	}
154	0	} while (BN_is_zero(k));
155
156		/* compute r the x-coordinate of generator * k */
157	0	if (!EC_POINT_mul(group, tmp_point, k, NULL, NULL, ctx)) {
158	0	ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
159	0	goto err;
160	0	}
161
162	0	if (!EC_POINT_get_affine_coordinates(group, tmp_point, X, NULL, ctx)) {
163	0	ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
164	0	goto err;
165	0	}
166
167	0	if (!BN_nnmod(r, X, order, ctx)) {
168	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
169	0	goto err;
170	0	}
171	0	} while (BN_is_zero(r));
172
173		/* compute the inverse of k */
174	0	if (!ossl_ec_group_do_inverse_ord(group, k, k, ctx)) {
175	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
176	0	goto err;
177	0	}
178
179		/* clear old values if necessary */
180	0	BN_clear_free(*rp);
181	0	BN_clear_free(*kinvp);
182		/* save the pre-computed values */
183	0	*rp = r;
184	0	*kinvp = k;
185	0	ret = 1;
186	0	err:
187	0	if (!ret) {
188	0	BN_clear_free(k);
189	0	BN_clear_free(r);
190	0	}
191	0	if (ctx != ctx_in)
192	0	BN_CTX_free(ctx);
193	0	EC_POINT_free(tmp_point);
194	0	BN_clear_free(X);
195	0	return ret;
196	0	}
197
198		int ossl_ecdsa_simple_sign_setup(EC_KEY eckey, BN_CTX ctx_in, BIGNUM **kinvp,
199		BIGNUM **rp)
200	0	{
201	0	return ecdsa_sign_setup(eckey, ctx_in, kinvp, rp, NULL, 0);
202	0	}
203
204		ECDSA_SIG ossl_ecdsa_simple_sign_sig(const unsigned char dgst, int dgst_len,
205		const BIGNUM in_kinv, const BIGNUM in_r,
206		EC_KEY *eckey)
207	0	{
208	0	int ok = 0, i;
209	0	int retries = 0;
210	0	BIGNUM kinv = NULL, s, *m = NULL;
211	0	const BIGNUM order, ckinv;
212	0	BN_CTX *ctx = NULL;
213	0	const EC_GROUP *group;
214	0	ECDSA_SIG *ret;
215	0	const BIGNUM *priv_key;
216
217	0	group = EC_KEY_get0_group(eckey);
218	0	priv_key = EC_KEY_get0_private_key(eckey);
219
220	0	if (group == NULL) {
221	0	ERR_raise(ERR_LIB_EC, ERR_R_PASSED_NULL_PARAMETER);
222	0	return NULL;
223	0	}
224	0	if (priv_key == NULL) {
225	0	ERR_raise(ERR_LIB_EC, EC_R_MISSING_PRIVATE_KEY);
226	0	return NULL;
227	0	}
228
229	0	if (!EC_KEY_can_sign(eckey)) {
230	0	ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
231	0	return NULL;
232	0	}
233
234	0	ret = ECDSA_SIG_new();
235	0	if (ret == NULL) {
236	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
237	0	return NULL;
238	0	}
239	0	ret->r = BN_new();
240	0	ret->s = BN_new();
241	0	if (ret->r == NULL \|\| ret->s == NULL) {
242	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
243	0	goto err;
244	0	}
245	0	s = ret->s;
246
247	0	if ((ctx = BN_CTX_new_ex(eckey->libctx)) == NULL
248	0	\|\| (m = BN_new()) == NULL) {
249	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
250	0	goto err;
251	0	}
252
253	0	order = EC_GROUP_get0_order(group);
254	0	i = BN_num_bits(order);
255		/*
256		* Need to truncate digest if it is too long: first truncate whole bytes.
257		*/
258	0	if (8 * dgst_len > i)
259	0	dgst_len = (i + 7) / 8;
260	0	if (!BN_bin2bn(dgst, dgst_len, m)) {
261	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
262	0	goto err;
263	0	}
264		/* If still too long, truncate remaining bits with a shift */
265	0	if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
266	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
267	0	goto err;
268	0	}
269	0	do {
270	0	if (in_kinv == NULL \|\| in_r == NULL) {
271	0	if (!ecdsa_sign_setup(eckey, ctx, &kinv, &ret->r, dgst, dgst_len)) {
272	0	ERR_raise(ERR_LIB_EC, ERR_R_ECDSA_LIB);
273	0	goto err;
274	0	}
275	0	ckinv = kinv;
276	0	} else {
277	0	ckinv = in_kinv;
278	0	if (BN_copy(ret->r, in_r) == NULL) {
279	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
280	0	goto err;
281	0	}
282	0	}
283
284		/*
285		* With only one multiplicant being in Montgomery domain
286		* multiplication yields real result without post-conversion.
287		* Also note that all operations but last are performed with
288		* zero-padded vectors. Last operation, BN_mod_mul_montgomery
289		* below, returns user-visible value with removed zero padding.
290		*/
291	0	if (!bn_to_mont_fixed_top(s, ret->r, group->mont_data, ctx)
292	0	\|\| !bn_mul_mont_fixed_top(s, s, priv_key, group->mont_data, ctx)) {
293	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
294	0	goto err;
295	0	}
296	0	if (!bn_mod_add_fixed_top(s, s, m, order)) {
297	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
298	0	goto err;
299	0	}
300		/*
301		* \|s\| can still be larger than modulus, because \|m\| can be. In
302		* such case we count on Montgomery reduction to tie it up.
303		*/
304	0	if (!bn_to_mont_fixed_top(s, s, group->mont_data, ctx)
305	0	\|\| !BN_mod_mul_montgomery(s, s, ckinv, group->mont_data, ctx)) {
306	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
307	0	goto err;
308	0	}
309
310	0	if (BN_is_zero(s)) {
311		/*
312		* if kinv and r have been supplied by the caller, don't
313		* generate new kinv and r values
314		*/
315	0	if (in_kinv != NULL && in_r != NULL) {
316	0	ERR_raise(ERR_LIB_EC, EC_R_NEED_NEW_SETUP_VALUES);
317	0	goto err;
318	0	}
319		/* Avoid infinite loops cause by invalid group parameters */
320	0	if (retries++ > MAX_ECDSA_SIGN_RETRIES) {
321	0	ERR_raise(ERR_LIB_EC, EC_R_TOO_MANY_RETRIES);
322	0	goto err;
323	0	}
324	0	} else {
325		/* s != 0 => we have a valid signature */
326	0	break;
327	0	}
328	0	} while (1);
329
330	0	ok = 1;
331	0	err:
332	0	if (!ok) {
333	0	ECDSA_SIG_free(ret);
334	0	ret = NULL;
335	0	}
336	0	BN_CTX_free(ctx);
337	0	BN_clear_free(m);
338	0	BN_clear_free(kinv);
339	0	return ret;
340	0	}
341
342		/*-
343		* returns
344		* 1: correct signature
345		* 0: incorrect signature
346		* -1: error
347		*/
348		int ossl_ecdsa_verify(int type, const unsigned char *dgst, int dgst_len,
349		const unsigned char sigbuf, int sig_len, EC_KEY eckey)
350	74	{
351	74	ECDSA_SIG *s;
352	74	const unsigned char *p = sigbuf;
353	74	unsigned char *der = NULL;
354	74	int derlen = -1;
355	74	int ret = -1;
356
357	74	s = ECDSA_SIG_new();
358	74	if (s == NULL)
359	0	return ret;
360	74	if (d2i_ECDSA_SIG(&s, &p, sig_len) == NULL)
361	54	goto err;
362		/* Ensure signature uses DER and doesn't have trailing garbage */
363	20	derlen = i2d_ECDSA_SIG(s, &der);
364	20	if (derlen != sig_len \|\| memcmp(sigbuf, der, derlen) != 0)
365	3	goto err;
366	17	ret = ECDSA_do_verify(dgst, dgst_len, s, eckey);
367	74	err:
368	74	OPENSSL_free(der);
369	74	ECDSA_SIG_free(s);
370	74	return ret;
371	17	}
372
373		int ossl_ecdsa_simple_verify_sig(const unsigned char *dgst, int dgst_len,
374		const ECDSA_SIG sig, EC_KEY eckey)
375	17	{
376	17	int ret = -1, i;
377	17	BN_CTX *ctx;
378	17	const BIGNUM *order;
379	17	BIGNUM u1, u2, m, X;
380	17	EC_POINT *point = NULL;
381	17	const EC_GROUP *group;
382	17	const EC_POINT *pub_key;
383
384		/* check input values */
385	17	if (eckey == NULL \|\| (group = EC_KEY_get0_group(eckey)) == NULL \|\|
386	17	(pub_key = EC_KEY_get0_public_key(eckey)) == NULL \|\| sig == NULL) {
387	0	ERR_raise(ERR_LIB_EC, EC_R_MISSING_PARAMETERS);
388	0	return -1;
389	0	}
390
391	17	if (!EC_KEY_can_sign(eckey)) {
392	0	ERR_raise(ERR_LIB_EC, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);
393	0	return -1;
394	0	}
395
396	17	ctx = BN_CTX_new_ex(eckey->libctx);
397	17	if (ctx == NULL) {
398	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
399	0	return -1;
400	0	}
401	17	BN_CTX_start(ctx);
402	17	u1 = BN_CTX_get(ctx);
403	17	u2 = BN_CTX_get(ctx);
404	17	m = BN_CTX_get(ctx);
405	17	X = BN_CTX_get(ctx);
406	17	if (X == NULL) {
407	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
408	0	goto err;
409	0	}
410
411	17	order = EC_GROUP_get0_order(group);
412	17	if (order == NULL) {
413	0	ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
414	0	goto err;
415	0	}
416
417	17	if (BN_is_zero(sig->r) \|\| BN_is_negative(sig->r) \|\|
418	17	BN_ucmp(sig->r, order) >= 0 \|\| BN_is_zero(sig->s) \|\|
419	17	BN_is_negative(sig->s) \|\| BN_ucmp(sig->s, order) >= 0) {
420	2	ERR_raise(ERR_LIB_EC, EC_R_BAD_SIGNATURE);
421	2	ret = 0; /* signature is invalid */
422	2	goto err;
423	2	}
424		/* calculate tmp1 = inv(S) mod order */
425	15	if (!ossl_ec_group_do_inverse_ord(group, u2, sig->s, ctx)) {
426	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
427	0	goto err;
428	0	}
429		/* digest -> m */
430	15	i = BN_num_bits(order);
431		/*
432		* Need to truncate digest if it is too long: first truncate whole bytes.
433		*/
434	15	if (8 * dgst_len > i)
435	3	dgst_len = (i + 7) / 8;
436	15	if (!BN_bin2bn(dgst, dgst_len, m)) {
437	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
438	0	goto err;
439	0	}
440		/* If still too long truncate remaining bits with a shift */
441	15	if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {
442	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
443	0	goto err;
444	0	}
445		/* u1 = m * tmp mod order */
446	15	if (!BN_mod_mul(u1, m, u2, order, ctx)) {
447	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
448	0	goto err;
449	0	}
450		/* u2 = r * w mod q */
451	15	if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {
452	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
453	0	goto err;
454	0	}
455
456	15	if ((point = EC_POINT_new(group)) == NULL) {
457	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
458	0	goto err;
459	0	}
460	15	if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) {
461	0	ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
462	0	goto err;
463	0	}
464
465	15	if (!EC_POINT_get_affine_coordinates(group, point, X, NULL, ctx)) {
466	0	ERR_raise(ERR_LIB_EC, ERR_R_EC_LIB);
467	0	goto err;
468	0	}
469
470	15	if (!BN_nnmod(u1, X, order, ctx)) {
471	0	ERR_raise(ERR_LIB_EC, ERR_R_BN_LIB);
472	0	goto err;
473	0	}
474		/* if the signature is correct u1 is equal to sig->r */
475	15	ret = (BN_ucmp(u1, sig->r) == 0);
476	17	err:
477	17	BN_CTX_end(ctx);
478	17	BN_CTX_free(ctx);
479	17	EC_POINT_free(point);
480	17	return ret;
481	15	}