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- /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
- * project 2006.
- */
- /* ====================================================================
- * Copyright (c) 2006 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 <openssl/evp.h>
-
- #include <openssl/asn1.h>
- #include <openssl/bn.h>
- #include <openssl/buf.h>
- #include <openssl/digest.h>
- #include <openssl/ec.h>
- #include <openssl/ec_key.h>
- #include <openssl/ecdh.h>
- #include <openssl/ecdsa.h>
- #include <openssl/err.h>
- #include <openssl/mem.h>
- #include <openssl/obj.h>
-
- #include "internal.h"
- #include "../ec/internal.h"
-
-
- 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;
- dctx = OPENSSL_malloc(sizeof(EC_PKEY_CTX));
- if (!dctx) {
- return 0;
- }
- memset(dctx, 0, sizeof(EC_PKEY_CTX));
- 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, 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 = BUF_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) {
- return;
- }
-
- if (dctx->gen_group) {
- EC_GROUP_free(dctx->gen_group);
- }
- if (dctx->co_key) {
- EC_KEY_free(dctx->co_key);
- }
- if (dctx->kdf_ukm) {
- OPENSSL_free(dctx->kdf_ukm);
- }
- OPENSSL_free(dctx);
- }
-
- static int pkey_ec_sign(EVP_PKEY_CTX *ctx, uint8_t *sig, size_t *siglen,
- const uint8_t *tbs, size_t tbslen) {
- int ret, type;
- unsigned int sltmp;
- EC_PKEY_CTX *dctx = ctx->data;
- EC_KEY *ec = ctx->pkey->pkey.ec;
-
- if (!sig) {
- *siglen = ECDSA_size(ec);
- return 1;
- } else if (*siglen < (size_t)ECDSA_size(ec)) {
- OPENSSL_PUT_ERROR(EVP, pkey_ec_sign, EVP_R_BUFFER_TOO_SMALL);
- return 0;
- }
-
- type = NID_sha1;
- if (dctx->md) {
- type = EVP_MD_type(dctx->md);
- }
-
- 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 uint8_t *sig, size_t siglen,
- const uint8_t *tbs, size_t tbslen) {
- int type;
- EC_PKEY_CTX *dctx = ctx->data;
- EC_KEY *ec = ctx->pkey->pkey.ec;
-
- type = NID_sha1;
- if (dctx->md) {
- type = EVP_MD_type(dctx->md);
- }
-
- return ECDSA_verify(type, tbs, tbslen, sig, siglen, ec);
- }
-
- static int pkey_ec_derive(EVP_PKEY_CTX *ctx, uint8_t *key,
- size_t *keylen) {
- int ret;
- size_t outlen;
- const EC_POINT *pubkey = NULL;
- EC_KEY *eckey;
- EC_PKEY_CTX *dctx = ctx->data;
-
- if (!ctx->pkey || !ctx->peerkey) {
- OPENSSL_PUT_ERROR(EVP, pkey_ec_derive, EVP_R_KEYS_NOT_SET);
- return 0;
- }
-
- eckey = dctx->co_key ? dctx->co_key : ctx->pkey->pkey.ec;
-
- if (!key) {
- const EC_GROUP *group;
- group = EC_KEY_get0_group(eckey);
- *keylen = (EC_GROUP_get_degree(group) + 7) / 8;
- return 1;
- }
- pubkey = EC_KEY_get0_public_key(ctx->peerkey->pkey.ec);
-
- /* 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 ret;
- }
- *keylen = ret;
- return 1;
- }
-
- static int pkey_ec_kdf_derive(EVP_PKEY_CTX *ctx, uint8_t *key,
- size_t *keylen) {
- EC_PKEY_CTX *dctx = ctx->data;
- uint8_t *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 ||
- !pkey_ec_derive(ctx, NULL, &ktmplen)) {
- return 0;
- }
- ktmp = OPENSSL_malloc(ktmplen);
- if (!ktmp) {
- return 0;
- }
- if (!pkey_ec_derive(ctx, ktmp, &ktmplen)) {
- goto err;
- }
-
- if (!ECDH_KDF_X9_62(key, *keylen, ktmp, ktmplen, dctx->kdf_ukm,
- dctx->kdf_ukmlen, dctx->kdf_md)) {
- goto err;
- }
- rv = 1;
-
- err:
- if (ktmp) {
- OPENSSL_cleanse(ktmp, ktmplen);
- OPENSSL_free(ktmp);
- }
- return rv;
- }
-
- 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) {
- OPENSSL_PUT_ERROR(EVP, pkey_ec_ctrl, EVP_R_INVALID_CURVE);
- return 0;
- }
- if (dctx->gen_group)
- EC_GROUP_free(dctx->gen_group);
- dctx->gen_group = group;
- return 1;
-
- 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_62)
- 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:
- if (dctx->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_type((const EVP_MD *)p2) != NID_sha1 &&
- EVP_MD_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
- EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
- EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
- EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
- EVP_MD_type((const EVP_MD *)p2) != NID_sha512) {
- OPENSSL_PUT_ERROR(EVP, pkey_ec_ctrl, EVP_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:
- return 1;
-
- default:
- 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 = 0;
-
- if (dctx->gen_group == NULL) {
- OPENSSL_PUT_ERROR(EVP, pkey_ec_paramgen, EVP_R_NO_PARAMETERS_SET);
- return 0;
- }
- ec = EC_KEY_new();
- if (!ec) {
- return 0;
- }
- ret = EC_KEY_set_group(ec, dctx->gen_group);
- if (ret) {
- EVP_PKEY_assign_EC_KEY(pkey, ec);
- } else {
- 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;
- if (ctx->pkey == NULL && dctx->gen_group == NULL) {
- OPENSSL_PUT_ERROR(EVP, pkey_ec_keygen, EVP_R_NO_PARAMETERS_SET);
- return 0;
- }
- ec = EC_KEY_new();
- if (!ec) {
- return 0;
- }
- EVP_PKEY_assign_EC_KEY(pkey, ec);
- if (ctx->pkey) {
- /* Note: if error return, pkey is freed by parent routine */
- if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey)) {
- return 0;
- }
- } else {
- if (!EC_KEY_set_group(ec, dctx->gen_group)) {
- return 0;
- }
- }
- return EC_KEY_generate_key(pkey->pkey.ec);
- }
-
- const EVP_PKEY_METHOD ec_pkey_meth = {
- EVP_PKEY_EC, 0 /* flags */, pkey_ec_init,
- pkey_ec_copy, pkey_ec_cleanup, 0 /* paramgen_init */,
- pkey_ec_paramgen, 0 /* keygen_init */, pkey_ec_keygen,
- 0 /* sign_init */, pkey_ec_sign, 0 /* verify_init */,
- pkey_ec_verify, 0 /* signctx_init */, 0 /* signctx */,
- 0 /* verifyctx_init */, 0 /* verifyctx */, 0 /* encrypt_init */,
- 0 /* encrypt */, 0 /* decrypt_init */, 0 /* decrypt */,
- 0 /* derive_init */, pkey_ec_kdf_derive, pkey_ec_ctrl,
- };
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