/src/openssl30/crypto/ec/ec_pmeth.c

Source (jump to first uncovered line)
/*
 * Copyright 2006-2021 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
 */

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

#include <stdio.h>
#include "internal/cryptlib.h"
#include <openssl/asn1t.h>
#include <openssl/x509.h>
#include <openssl/ec.h>
#include "ec_local.h"
#include <openssl/evp.h>
#include "crypto/evp.h"

/* EC pkey context structure */

typedef struct {
    /* Key and paramgen group */
    EC_GROUP *gen_group;
    /* message digest */
    const EVP_MD *md;
    /* Duplicate key if custom cofactor needed */
    EC_KEY *co_key;
    /* Cofactor mode */
    signed char cofactor_mode;
    /* KDF (if any) to use for ECDH */
    char kdf_type;
    /* Message digest to use for key derivation */
    const EVP_MD *kdf_md;
    /* User key material */
    unsigned char *kdf_ukm;
    size_t kdf_ukmlen;
    /* KDF output length */
    size_t kdf_outlen;
} EC_PKEY_CTX;

static int pkey_ec_init(EVP_PKEY_CTX *ctx)
{
    EC_PKEY_CTX *dctx;

    if ((dctx = OPENSSL_zalloc(sizeof(*dctx))) == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        return 0;
    }

    dctx->cofactor_mode = -1;
    dctx->kdf_type = EVP_PKEY_ECDH_KDF_NONE;
    ctx->data = dctx;
    return 1;
}

static int pkey_ec_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src)
{
    EC_PKEY_CTX *dctx, *sctx;
    if (!pkey_ec_init(dst))
        return 0;
    sctx = src->data;
    dctx = dst->data;
    if (sctx->gen_group) {
        dctx->gen_group = EC_GROUP_dup(sctx->gen_group);
        if (!dctx->gen_group)
            return 0;
    }
    dctx->md = sctx->md;

    if (sctx->co_key) {
        dctx->co_key = EC_KEY_dup(sctx->co_key);
        if (!dctx->co_key)
            return 0;
    }
    dctx->kdf_type = sctx->kdf_type;
    dctx->kdf_md = sctx->kdf_md;
    dctx->kdf_outlen = sctx->kdf_outlen;
    if (sctx->kdf_ukm) {
        dctx->kdf_ukm = OPENSSL_memdup(sctx->kdf_ukm, sctx->kdf_ukmlen);
        if (!dctx->kdf_ukm)
            return 0;
    } else
        dctx->kdf_ukm = NULL;
    dctx->kdf_ukmlen = sctx->kdf_ukmlen;
    return 1;
}

static void pkey_ec_cleanup(EVP_PKEY_CTX *ctx)
{
    EC_PKEY_CTX *dctx = ctx->data;
    if (dctx != NULL) {
        EC_GROUP_free(dctx->gen_group);
        EC_KEY_free(dctx->co_key);
        OPENSSL_free(dctx->kdf_ukm);
        OPENSSL_free(dctx);
        ctx->data = NULL;
    }
}

static int pkey_ec_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
                        const unsigned char *tbs, size_t tbslen)
{
    int ret, type;
    unsigned int sltmp;
    EC_PKEY_CTX *dctx = ctx->data;
    /*
     * Discard const. Its marked as const because this may be a cached copy of
     * the "real" key. These calls don't make any modifications that need to
     * be reflected back in the "original" key.
     */
    EC_KEY *ec = (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);
    const int sig_sz = ECDSA_size(ec);

    /* ensure cast to size_t is safe */
    if (!ossl_assert(sig_sz > 0))
        return 0;

    if (sig == NULL) {
        *siglen = (size_t)sig_sz;
        return 1;
    }

    if (*siglen < (size_t)sig_sz) {
        ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
        return 0;
    }

    type = (dctx->md != NULL) ? EVP_MD_get_type(dctx->md) : NID_sha1;

    ret = ECDSA_sign(type, tbs, tbslen, sig, &sltmp, ec);

    if (ret <= 0)
        return ret;
    *siglen = (size_t)sltmp;
    return 1;
}

static int pkey_ec_verify(EVP_PKEY_CTX *ctx,
                          const unsigned char *sig, size_t siglen,
                          const unsigned char *tbs, size_t tbslen)
{
    int ret, type;
    EC_PKEY_CTX *dctx = ctx->data;
    /*
     * Discard const. Its marked as const because this may be a cached copy of
     * the "real" key. These calls don't make any modifications that need to
     * be reflected back in the "original" key.
     */
    EC_KEY *ec = (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);

    if (dctx->md)
        type = EVP_MD_get_type(dctx->md);
    else
        type = NID_sha1;

    ret = ECDSA_verify(type, tbs, tbslen, sig, siglen, ec);

    return ret;
}

#ifndef OPENSSL_NO_EC
static int pkey_ec_derive(EVP_PKEY_CTX *ctx, unsigned char *key, size_t *keylen)
{
    int ret;
    size_t outlen;
    const EC_POINT *pubkey = NULL;
    EC_KEY *eckey;
    const EC_KEY *eckeypub;
    EC_PKEY_CTX *dctx = ctx->data;

    if (ctx->pkey == NULL || ctx->peerkey == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_KEYS_NOT_SET);
        return 0;
    }
    eckeypub = EVP_PKEY_get0_EC_KEY(ctx->peerkey);
    if (eckeypub == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_KEYS_NOT_SET);
        return 0;
    }

    eckey = dctx->co_key ? dctx->co_key
                         : (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);

    if (!key) {
        const EC_GROUP *group;
        group = EC_KEY_get0_group(eckey);

        if (group == NULL)
            return 0;
        *keylen = (EC_GROUP_get_degree(group) + 7) / 8;
        return 1;
    }
    pubkey = EC_KEY_get0_public_key(eckeypub);

    /*
     * NB: unlike PKCS#3 DH, if *outlen is less than maximum size this is not
     * an error, the result is truncated.
     */

    outlen = *keylen;

    ret = ECDH_compute_key(key, outlen, pubkey, eckey, 0);
    if (ret <= 0)
        return 0;
    *keylen = ret;
    return 1;
}

static int pkey_ec_kdf_derive(EVP_PKEY_CTX *ctx,
                              unsigned char *key, size_t *keylen)
{
    EC_PKEY_CTX *dctx = ctx->data;
    unsigned char *ktmp = NULL;
    size_t ktmplen;
    int rv = 0;
    if (dctx->kdf_type == EVP_PKEY_ECDH_KDF_NONE)
        return pkey_ec_derive(ctx, key, keylen);
    if (!key) {
        *keylen = dctx->kdf_outlen;
        return 1;
    }
    if (*keylen != dctx->kdf_outlen)
        return 0;
    if (!pkey_ec_derive(ctx, NULL, &ktmplen))
        return 0;
    if ((ktmp = OPENSSL_malloc(ktmplen)) == NULL) {
        ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
        return 0;
    }
    if (!pkey_ec_derive(ctx, ktmp, &ktmplen))
        goto err;
    /* Do KDF stuff */
    if (!ossl_ecdh_kdf_X9_63(key, *keylen, ktmp, ktmplen,
                             dctx->kdf_ukm, dctx->kdf_ukmlen, dctx->kdf_md,
                             ctx->libctx, ctx->propquery))
        goto err;
    rv = 1;

 err:
    OPENSSL_clear_free(ktmp, ktmplen);
    return rv;
}
#endif

static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
{
    EC_PKEY_CTX *dctx = ctx->data;
    EC_GROUP *group;
    switch (type) {
    case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID:
        group = EC_GROUP_new_by_curve_name(p1);
        if (group == NULL) {
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_CURVE);
            return 0;
        }
        EC_GROUP_free(dctx->gen_group);
        dctx->gen_group = group;
        return 1;

    case EVP_PKEY_CTRL_EC_PARAM_ENC:
        if (!dctx->gen_group) {
            ERR_raise(ERR_LIB_EC, EC_R_NO_PARAMETERS_SET);
            return 0;
        }
        EC_GROUP_set_asn1_flag(dctx->gen_group, p1);
        return 1;

#ifndef OPENSSL_NO_EC
    case EVP_PKEY_CTRL_EC_ECDH_COFACTOR:
        if (p1 == -2) {
            if (dctx->cofactor_mode != -1)
                return dctx->cofactor_mode;
            else {
                const EC_KEY *ec_key = EVP_PKEY_get0_EC_KEY(ctx->pkey);
                return EC_KEY_get_flags(ec_key) & EC_FLAG_COFACTOR_ECDH ? 1 : 0;
            }
        } else if (p1 < -1 || p1 > 1)
            return -2;
        dctx->cofactor_mode = p1;
        if (p1 != -1) {
            EC_KEY *ec_key = (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);

            /*
             * We discarded the "const" above. This will only work if the key is
             * a "real" legacy key, and not a cached copy of a provided key
             */
            if (evp_pkey_is_provided(ctx->pkey)) {
                ERR_raise(ERR_LIB_EC, ERR_R_UNSUPPORTED);
                return 0;
            }
            if (!ec_key->group)
                return -2;
            /* If cofactor is 1 cofactor mode does nothing */
            if (BN_is_one(ec_key->group->cofactor))
                return 1;
            if (!dctx->co_key) {
                dctx->co_key = EC_KEY_dup(ec_key);
                if (!dctx->co_key)
                    return 0;
            }
            if (p1)
                EC_KEY_set_flags(dctx->co_key, EC_FLAG_COFACTOR_ECDH);
            else
                EC_KEY_clear_flags(dctx->co_key, EC_FLAG_COFACTOR_ECDH);
        } else {
            EC_KEY_free(dctx->co_key);
            dctx->co_key = NULL;
        }
        return 1;
#endif

    case EVP_PKEY_CTRL_EC_KDF_TYPE:
        if (p1 == -2)
            return dctx->kdf_type;
        if (p1 != EVP_PKEY_ECDH_KDF_NONE && p1 != EVP_PKEY_ECDH_KDF_X9_63)
            return -2;
        dctx->kdf_type = p1;
        return 1;

    case EVP_PKEY_CTRL_EC_KDF_MD:
        dctx->kdf_md = p2;
        return 1;

    case EVP_PKEY_CTRL_GET_EC_KDF_MD:
        *(const EVP_MD **)p2 = dctx->kdf_md;
        return 1;

    case EVP_PKEY_CTRL_EC_KDF_OUTLEN:
        if (p1 <= 0)
            return -2;
        dctx->kdf_outlen = (size_t)p1;
        return 1;

    case EVP_PKEY_CTRL_GET_EC_KDF_OUTLEN:
        *(int *)p2 = dctx->kdf_outlen;
        return 1;

    case EVP_PKEY_CTRL_EC_KDF_UKM:
        OPENSSL_free(dctx->kdf_ukm);
        dctx->kdf_ukm = p2;
        if (p2)
            dctx->kdf_ukmlen = p1;
        else
            dctx->kdf_ukmlen = 0;
        return 1;

    case EVP_PKEY_CTRL_GET_EC_KDF_UKM:
        *(unsigned char **)p2 = dctx->kdf_ukm;
        return dctx->kdf_ukmlen;

    case EVP_PKEY_CTRL_MD:
        if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha384 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha512 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_224 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_256 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_384 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_512 &&
            EVP_MD_get_type((const EVP_MD *)p2) != NID_sm3) {
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_DIGEST_TYPE);
            return 0;
        }
        dctx->md = p2;
        return 1;

    case EVP_PKEY_CTRL_GET_MD:
        *(const EVP_MD **)p2 = dctx->md;
        return 1;

    case EVP_PKEY_CTRL_PEER_KEY:
        /* Default behaviour is OK */
    case EVP_PKEY_CTRL_DIGESTINIT:
    case EVP_PKEY_CTRL_PKCS7_SIGN:
    case EVP_PKEY_CTRL_CMS_SIGN:
        return 1;

    default:
        return -2;

    }
}

static int pkey_ec_ctrl_str(EVP_PKEY_CTX *ctx,
                            const char *type, const char *value)
{
    if (strcmp(type, "ec_paramgen_curve") == 0) {
        int nid;
        nid = EC_curve_nist2nid(value);
        if (nid == NID_undef)
            nid = OBJ_sn2nid(value);
        if (nid == NID_undef)
            nid = OBJ_ln2nid(value);
        if (nid == NID_undef) {
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_CURVE);
            return 0;
        }
        return EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx, nid);
    } else if (strcmp(type, "ec_param_enc") == 0) {
        int param_enc;
        if (strcmp(value, "explicit") == 0)
            param_enc = 0;
        else if (strcmp(value, "named_curve") == 0)
            param_enc = OPENSSL_EC_NAMED_CURVE;
        else
            return -2;
        return EVP_PKEY_CTX_set_ec_param_enc(ctx, param_enc);
    } else if (strcmp(type, "ecdh_kdf_md") == 0) {
        const EVP_MD *md;
        if ((md = EVP_get_digestbyname(value)) == NULL) {
            ERR_raise(ERR_LIB_EC, EC_R_INVALID_DIGEST);
            return 0;
        }
        return EVP_PKEY_CTX_set_ecdh_kdf_md(ctx, md);
    } else if (strcmp(type, "ecdh_cofactor_mode") == 0) {
        int co_mode;
        co_mode = atoi(value);
        return EVP_PKEY_CTX_set_ecdh_cofactor_mode(ctx, co_mode);
    }

    return -2;
}

static int pkey_ec_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
    EC_KEY *ec = NULL;
    EC_PKEY_CTX *dctx = ctx->data;
    int ret;

    if (dctx->gen_group == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_NO_PARAMETERS_SET);
        return 0;
    }
    ec = EC_KEY_new();
    if (ec == NULL)
        return 0;
    if (!(ret = EC_KEY_set_group(ec, dctx->gen_group))
        || !ossl_assert(ret = EVP_PKEY_assign_EC_KEY(pkey, ec)))
        EC_KEY_free(ec);
    return ret;
}

static int pkey_ec_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
{
    EC_KEY *ec = NULL;
    EC_PKEY_CTX *dctx = ctx->data;
    int ret;

    if (ctx->pkey == NULL && dctx->gen_group == NULL) {
        ERR_raise(ERR_LIB_EC, EC_R_NO_PARAMETERS_SET);
        return 0;
    }
    ec = EC_KEY_new();
    if (ec == NULL)
        return 0;
    if (!ossl_assert(EVP_PKEY_assign_EC_KEY(pkey, ec))) {
        EC_KEY_free(ec);
        return 0;
    }
    /* Note: if error is returned, we count on caller to free pkey->pkey.ec */
    if (ctx->pkey != NULL)
        ret = EVP_PKEY_copy_parameters(pkey, ctx->pkey);
    else
        ret = EC_KEY_set_group(ec, dctx->gen_group);

    return ret ? EC_KEY_generate_key(ec) : 0;
}

static const EVP_PKEY_METHOD ec_pkey_meth = {
    EVP_PKEY_EC,
    0,
    pkey_ec_init,
    pkey_ec_copy,
    pkey_ec_cleanup,

    0,
    pkey_ec_paramgen,

    0,
    pkey_ec_keygen,

    0,
    pkey_ec_sign,

    0,
    pkey_ec_verify,

    0, 0,

    0, 0, 0, 0,

    0,
    0,

    0,
    0,

    0,
#ifndef OPENSSL_NO_EC
    pkey_ec_kdf_derive,
#else
    0,
#endif
    pkey_ec_ctrl,
    pkey_ec_ctrl_str
};

const EVP_PKEY_METHOD *ossl_ec_pkey_method(void)
{
    return &ec_pkey_meth;
}

Coverage Report

Created: 2023-09-25 06:45

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2006-2021 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		* ECDH and ECDSA low level APIs are deprecated for public use, but still ok
12		* for internal use.
13		*/
14		#include "internal/deprecated.h"
15
16		#include <stdio.h>
17		#include "internal/cryptlib.h"
18		#include <openssl/asn1t.h>
19		#include <openssl/x509.h>
20		#include <openssl/ec.h>
21		#include "ec_local.h"
22		#include <openssl/evp.h>
23		#include "crypto/evp.h"
24
25		/* EC pkey context structure */
26
27		typedef struct {
28		/* Key and paramgen group */
29		EC_GROUP *gen_group;
30		/* message digest */
31		const EVP_MD *md;
32		/* Duplicate key if custom cofactor needed */
33		EC_KEY *co_key;
34		/* Cofactor mode */
35		signed char cofactor_mode;
36		/* KDF (if any) to use for ECDH */
37		char kdf_type;
38		/* Message digest to use for key derivation */
39		const EVP_MD *kdf_md;
40		/* User key material */
41		unsigned char *kdf_ukm;
42		size_t kdf_ukmlen;
43		/* KDF output length */
44		size_t kdf_outlen;
45		} EC_PKEY_CTX;
46
47		static int pkey_ec_init(EVP_PKEY_CTX *ctx)
48	3.88k	{
49	3.88k	EC_PKEY_CTX *dctx;
50
51	3.88k	if ((dctx = OPENSSL_zalloc(sizeof(*dctx))) == NULL) {
52	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
53	0	return 0;
54	0	}
55
56	3.88k	dctx->cofactor_mode = -1;
57	3.88k	dctx->kdf_type = EVP_PKEY_ECDH_KDF_NONE;
58	3.88k	ctx->data = dctx;
59	3.88k	return 1;
60	3.88k	}
61
62		static int pkey_ec_copy(EVP_PKEY_CTX dst, const EVP_PKEY_CTX src)
63	963	{
64	963	EC_PKEY_CTX dctx, sctx;
65	963	if (!pkey_ec_init(dst))
66	0	return 0;
67	963	sctx = src->data;
68	963	dctx = dst->data;
69	963	if (sctx->gen_group) {
70	0	dctx->gen_group = EC_GROUP_dup(sctx->gen_group);
71	0	if (!dctx->gen_group)
72	0	return 0;
73	0	}
74	963	dctx->md = sctx->md;
75
76	963	if (sctx->co_key) {
77	0	dctx->co_key = EC_KEY_dup(sctx->co_key);
78	0	if (!dctx->co_key)
79	0	return 0;
80	0	}
81	963	dctx->kdf_type = sctx->kdf_type;
82	963	dctx->kdf_md = sctx->kdf_md;
83	963	dctx->kdf_outlen = sctx->kdf_outlen;
84	963	if (sctx->kdf_ukm) {
85	0	dctx->kdf_ukm = OPENSSL_memdup(sctx->kdf_ukm, sctx->kdf_ukmlen);
86	0	if (!dctx->kdf_ukm)
87	0	return 0;
88	0	} else
89	963	dctx->kdf_ukm = NULL;
90	963	dctx->kdf_ukmlen = sctx->kdf_ukmlen;
91	963	return 1;
92	963	}
93
94		static void pkey_ec_cleanup(EVP_PKEY_CTX *ctx)
95	3.88k	{
96	3.88k	EC_PKEY_CTX *dctx = ctx->data;
97	3.88k	if (dctx != NULL) {
98	3.88k	EC_GROUP_free(dctx->gen_group);
99	3.88k	EC_KEY_free(dctx->co_key);
100	3.88k	OPENSSL_free(dctx->kdf_ukm);
101	3.88k	OPENSSL_free(dctx);
102	3.88k	ctx->data = NULL;
103	3.88k	}
104	3.88k	}
105
106		static int pkey_ec_sign(EVP_PKEY_CTX ctx, unsigned char sig, size_t *siglen,
107		const unsigned char *tbs, size_t tbslen)
108	782	{
109	782	int ret, type;
110	782	unsigned int sltmp;
111	782	EC_PKEY_CTX *dctx = ctx->data;
112		/*
113		* Discard const. Its marked as const because this may be a cached copy of
114		* the "real" key. These calls don't make any modifications that need to
115		* be reflected back in the "original" key.
116		*/
117	782	EC_KEY ec = (EC_KEY )EVP_PKEY_get0_EC_KEY(ctx->pkey);
118	782	const int sig_sz = ECDSA_size(ec);
119
120		/* ensure cast to size_t is safe */
121	782	if (!ossl_assert(sig_sz > 0))
122	0	return 0;
123
124	782	if (sig == NULL) {
125	0	*siglen = (size_t)sig_sz;
126	0	return 1;
127	0	}
128
129	782	if (*siglen < (size_t)sig_sz) {
130	0	ERR_raise(ERR_LIB_EC, EC_R_BUFFER_TOO_SMALL);
131	0	return 0;
132	0	}
133
134	782	type = (dctx->md != NULL) ? EVP_MD_get_type(dctx->md) : NID_sha1;
135
136	782	ret = ECDSA_sign(type, tbs, tbslen, sig, &sltmp, ec);
137
138	782	if (ret <= 0)
139	0	return ret;
140	782	*siglen = (size_t)sltmp;
141	782	return 1;
142	782	}
143
144		static int pkey_ec_verify(EVP_PKEY_CTX *ctx,
145		const unsigned char *sig, size_t siglen,
146		const unsigned char *tbs, size_t tbslen)
147	181	{
148	181	int ret, type;
149	181	EC_PKEY_CTX *dctx = ctx->data;
150		/*
151		* Discard const. Its marked as const because this may be a cached copy of
152		* the "real" key. These calls don't make any modifications that need to
153		* be reflected back in the "original" key.
154		*/
155	181	EC_KEY ec = (EC_KEY )EVP_PKEY_get0_EC_KEY(ctx->pkey);
156
157	181	if (dctx->md)
158	181	type = EVP_MD_get_type(dctx->md);
159	0	else
160	0	type = NID_sha1;
161
162	181	ret = ECDSA_verify(type, tbs, tbslen, sig, siglen, ec);
163
164	181	return ret;
165	181	}
166
167		#ifndef OPENSSL_NO_EC
168		static int pkey_ec_derive(EVP_PKEY_CTX ctx, unsigned char key, size_t *keylen)
169		{
170		int ret;
171		size_t outlen;
172		const EC_POINT *pubkey = NULL;
173		EC_KEY *eckey;
174		const EC_KEY *eckeypub;
175		EC_PKEY_CTX *dctx = ctx->data;
176
177		if (ctx->pkey == NULL \|\| ctx->peerkey == NULL) {
178		ERR_raise(ERR_LIB_EC, EC_R_KEYS_NOT_SET);
179		return 0;
180		}
181		eckeypub = EVP_PKEY_get0_EC_KEY(ctx->peerkey);
182		if (eckeypub == NULL) {
183		ERR_raise(ERR_LIB_EC, EC_R_KEYS_NOT_SET);
184		return 0;
185		}
186
187		eckey = dctx->co_key ? dctx->co_key
188		: (EC_KEY *)EVP_PKEY_get0_EC_KEY(ctx->pkey);
189
190		if (!key) {
191		const EC_GROUP *group;
192		group = EC_KEY_get0_group(eckey);
193
194		if (group == NULL)
195		return 0;
196		*keylen = (EC_GROUP_get_degree(group) + 7) / 8;
197		return 1;
198		}
199		pubkey = EC_KEY_get0_public_key(eckeypub);
200
201		/*
202		* NB: unlike PKCS#3 DH, if *outlen is less than maximum size this is not
203		* an error, the result is truncated.
204		*/
205
206		outlen = *keylen;
207
208		ret = ECDH_compute_key(key, outlen, pubkey, eckey, 0);
209		if (ret <= 0)
210		return 0;
211		*keylen = ret;
212		return 1;
213		}
214
215		static int pkey_ec_kdf_derive(EVP_PKEY_CTX *ctx,
216		unsigned char key, size_t keylen)
217	872	{
218	872	EC_PKEY_CTX *dctx = ctx->data;
219	872	unsigned char *ktmp = NULL;
220	872	size_t ktmplen;
221	872	int rv = 0;
222	872	if (dctx->kdf_type == EVP_PKEY_ECDH_KDF_NONE)
223	872	return pkey_ec_derive(ctx, key, keylen);
224	0	if (!key) {
225	0	*keylen = dctx->kdf_outlen;
226	0	return 1;
227	0	}
228	0	if (*keylen != dctx->kdf_outlen)
229	0	return 0;
230	0	if (!pkey_ec_derive(ctx, NULL, &ktmplen))
231	0	return 0;
232	0	if ((ktmp = OPENSSL_malloc(ktmplen)) == NULL) {
233	0	ERR_raise(ERR_LIB_EC, ERR_R_MALLOC_FAILURE);
234	0	return 0;
235	0	}
236	0	if (!pkey_ec_derive(ctx, ktmp, &ktmplen))
237	0	goto err;
238		/* Do KDF stuff */
239	0	if (!ossl_ecdh_kdf_X9_63(key, *keylen, ktmp, ktmplen,
240	0	dctx->kdf_ukm, dctx->kdf_ukmlen, dctx->kdf_md,
241	0	ctx->libctx, ctx->propquery))
242	0	goto err;
243	0	rv = 1;
244
245	0	err:
246	0	OPENSSL_clear_free(ktmp, ktmplen);
247	0	return rv;
248	0	}
249		#endif
250
251		static int pkey_ec_ctrl(EVP_PKEY_CTX ctx, int type, int p1, void p2)
252		{
253		EC_PKEY_CTX *dctx = ctx->data;
254		EC_GROUP *group;
255		switch (type) {
256		case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID:
257		group = EC_GROUP_new_by_curve_name(p1);
258		if (group == NULL) {
259		ERR_raise(ERR_LIB_EC, EC_R_INVALID_CURVE);
260		return 0;
261		}
262		EC_GROUP_free(dctx->gen_group);
263		dctx->gen_group = group;
264		return 1;
265
266		case EVP_PKEY_CTRL_EC_PARAM_ENC:
267		if (!dctx->gen_group) {
268		ERR_raise(ERR_LIB_EC, EC_R_NO_PARAMETERS_SET);
269		return 0;
270		}
271		EC_GROUP_set_asn1_flag(dctx->gen_group, p1);
272		return 1;
273
274		#ifndef OPENSSL_NO_EC
275		case EVP_PKEY_CTRL_EC_ECDH_COFACTOR:
276		if (p1 == -2) {
277		if (dctx->cofactor_mode != -1)
278		return dctx->cofactor_mode;
279		else {
280		const EC_KEY *ec_key = EVP_PKEY_get0_EC_KEY(ctx->pkey);
281		return EC_KEY_get_flags(ec_key) & EC_FLAG_COFACTOR_ECDH ? 1 : 0;
282		}
283		} else if (p1 < -1 \|\| p1 > 1)
284		return -2;
285		dctx->cofactor_mode = p1;
286		if (p1 != -1) {
287		EC_KEY ec_key = (EC_KEY )EVP_PKEY_get0_EC_KEY(ctx->pkey);
288
289		/*
290		* We discarded the "const" above. This will only work if the key is
291		* a "real" legacy key, and not a cached copy of a provided key
292		*/
293		if (evp_pkey_is_provided(ctx->pkey)) {
294		ERR_raise(ERR_LIB_EC, ERR_R_UNSUPPORTED);
295		return 0;
296		}
297		if (!ec_key->group)
298		return -2;
299		/* If cofactor is 1 cofactor mode does nothing */
300		if (BN_is_one(ec_key->group->cofactor))
301		return 1;
302		if (!dctx->co_key) {
303		dctx->co_key = EC_KEY_dup(ec_key);
304		if (!dctx->co_key)
305		return 0;
306		}
307		if (p1)
308		EC_KEY_set_flags(dctx->co_key, EC_FLAG_COFACTOR_ECDH);
309		else
310		EC_KEY_clear_flags(dctx->co_key, EC_FLAG_COFACTOR_ECDH);
311		} else {
312		EC_KEY_free(dctx->co_key);
313		dctx->co_key = NULL;
314		}
315		return 1;
316		#endif
317
318		case EVP_PKEY_CTRL_EC_KDF_TYPE:
319		if (p1 == -2)
320		return dctx->kdf_type;
321		if (p1 != EVP_PKEY_ECDH_KDF_NONE && p1 != EVP_PKEY_ECDH_KDF_X9_63)
322		return -2;
323		dctx->kdf_type = p1;
324		return 1;
325
326		case EVP_PKEY_CTRL_EC_KDF_MD:
327		dctx->kdf_md = p2;
328		return 1;
329
330		case EVP_PKEY_CTRL_GET_EC_KDF_MD:
331		(const EVP_MD *)p2 = dctx->kdf_md;
332		return 1;
333
334		case EVP_PKEY_CTRL_EC_KDF_OUTLEN:
335		if (p1 <= 0)
336		return -2;
337		dctx->kdf_outlen = (size_t)p1;
338		return 1;
339
340		case EVP_PKEY_CTRL_GET_EC_KDF_OUTLEN:
341		(int )p2 = dctx->kdf_outlen;
342		return 1;
343
344		case EVP_PKEY_CTRL_EC_KDF_UKM:
345		OPENSSL_free(dctx->kdf_ukm);
346		dctx->kdf_ukm = p2;
347		if (p2)
348		dctx->kdf_ukmlen = p1;
349		else
350		dctx->kdf_ukmlen = 0;
351		return 1;
352
353		case EVP_PKEY_CTRL_GET_EC_KDF_UKM:
354		(unsigned char *)p2 = dctx->kdf_ukm;
355		return dctx->kdf_ukmlen;
356
357		case EVP_PKEY_CTRL_MD:
358		if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 &&
359		EVP_MD_get_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
360		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 &&
361		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256 &&
362		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha384 &&
363		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha512 &&
364		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_224 &&
365		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_256 &&
366		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_384 &&
367		EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_512 &&
368		EVP_MD_get_type((const EVP_MD *)p2) != NID_sm3) {
369		ERR_raise(ERR_LIB_EC, EC_R_INVALID_DIGEST_TYPE);
370		return 0;
371		}
372		dctx->md = p2;
373		return 1;
374
375		case EVP_PKEY_CTRL_GET_MD:
376		(const EVP_MD *)p2 = dctx->md;
377		return 1;
378
379		case EVP_PKEY_CTRL_PEER_KEY:
380		/* Default behaviour is OK */
381		case EVP_PKEY_CTRL_DIGESTINIT:
382		case EVP_PKEY_CTRL_PKCS7_SIGN:
383		case EVP_PKEY_CTRL_CMS_SIGN:
384		return 1;
385
386		default:
387		return -2;
388
389		}
390		}
391
392		static int pkey_ec_ctrl_str(EVP_PKEY_CTX *ctx,
393		const char type, const char value)
394	0	{
395	0	if (strcmp(type, "ec_paramgen_curve") == 0) {
396	0	int nid;
397	0	nid = EC_curve_nist2nid(value);
398	0	if (nid == NID_undef)
399	0	nid = OBJ_sn2nid(value);
400	0	if (nid == NID_undef)
401	0	nid = OBJ_ln2nid(value);
402	0	if (nid == NID_undef) {
403	0	ERR_raise(ERR_LIB_EC, EC_R_INVALID_CURVE);
404	0	return 0;
405	0	}
406	0	return EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx, nid);
407	0	} else if (strcmp(type, "ec_param_enc") == 0) {
408	0	int param_enc;
409	0	if (strcmp(value, "explicit") == 0)
410	0	param_enc = 0;
411	0	else if (strcmp(value, "named_curve") == 0)
412	0	param_enc = OPENSSL_EC_NAMED_CURVE;
413	0	else
414	0	return -2;
415	0	return EVP_PKEY_CTX_set_ec_param_enc(ctx, param_enc);
416	0	} else if (strcmp(type, "ecdh_kdf_md") == 0) {
417	0	const EVP_MD *md;
418	0	if ((md = EVP_get_digestbyname(value)) == NULL) {
419	0	ERR_raise(ERR_LIB_EC, EC_R_INVALID_DIGEST);
420	0	return 0;
421	0	}
422	0	return EVP_PKEY_CTX_set_ecdh_kdf_md(ctx, md);
423	0	} else if (strcmp(type, "ecdh_cofactor_mode") == 0) {
424	0	int co_mode;
425	0	co_mode = atoi(value);
426	0	return EVP_PKEY_CTX_set_ecdh_cofactor_mode(ctx, co_mode);
427	0	}
428
429	0	return -2;
430	0	}
431
432		static int pkey_ec_paramgen(EVP_PKEY_CTX ctx, EVP_PKEY pkey)
433	665	{
434	665	EC_KEY *ec = NULL;
435	665	EC_PKEY_CTX *dctx = ctx->data;
436	665	int ret;
437
438	665	if (dctx->gen_group == NULL) {
439	0	ERR_raise(ERR_LIB_EC, EC_R_NO_PARAMETERS_SET);
440	0	return 0;
441	0	}
442	665	ec = EC_KEY_new();
443	665	if (ec == NULL)
444	0	return 0;
445	665	if (!(ret = EC_KEY_set_group(ec, dctx->gen_group))
446	665	\|\| !ossl_assert(ret = EVP_PKEY_assign_EC_KEY(pkey, ec)))
447	0	EC_KEY_free(ec);
448	665	return ret;
449	665	}
450
451		static int pkey_ec_keygen(EVP_PKEY_CTX ctx, EVP_PKEY pkey)
452	862	{
453	862	EC_KEY *ec = NULL;
454	862	EC_PKEY_CTX *dctx = ctx->data;
455	862	int ret;
456
457	862	if (ctx->pkey == NULL && dctx->gen_group == NULL) {
458	0	ERR_raise(ERR_LIB_EC, EC_R_NO_PARAMETERS_SET);
459	0	return 0;
460	0	}
461	862	ec = EC_KEY_new();
462	862	if (ec == NULL)
463	0	return 0;
464	862	if (!ossl_assert(EVP_PKEY_assign_EC_KEY(pkey, ec))) {
465	0	EC_KEY_free(ec);
466	0	return 0;
467	0	}
468		/* Note: if error is returned, we count on caller to free pkey->pkey.ec */
469	862	if (ctx->pkey != NULL)
470	243	ret = EVP_PKEY_copy_parameters(pkey, ctx->pkey);
471	619	else
472	619	ret = EC_KEY_set_group(ec, dctx->gen_group);
473
474	862	return ret ? EC_KEY_generate_key(ec) : 0;
475	862	}
476
477		static const EVP_PKEY_METHOD ec_pkey_meth = {
478		EVP_PKEY_EC,
479		0,
480		pkey_ec_init,
481		pkey_ec_copy,
482		pkey_ec_cleanup,
483
484		0,
485		pkey_ec_paramgen,
486
487		0,
488		pkey_ec_keygen,
489
490		0,
491		pkey_ec_sign,
492
493		0,
494		pkey_ec_verify,
495
496		0, 0,
497
498		0, 0, 0, 0,
499
500		0,
501		0,
502
503		0,
504		0,
505
506		0,
507		#ifndef OPENSSL_NO_EC
508		pkey_ec_kdf_derive,
509		#else
510		0,
511		#endif
512		pkey_ec_ctrl,
513		pkey_ec_ctrl_str
514		};
515
516		const EVP_PKEY_METHOD *ossl_ec_pkey_method(void)
517	0	{
518	0	return &ec_pkey_meth;
519	0	}