1 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
4 /* ====================================================================
5 * Copyright (c) 2006 The OpenSSL Project. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
19 * 3. All advertising materials mentioning features or use of this
20 * software must display the following acknowledgment:
21 * "This product includes software developed by the OpenSSL Project
22 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
25 * endorse or promote products derived from this software without
26 * prior written permission. For written permission, please contact
27 * licensing@OpenSSL.org.
29 * 5. Products derived from this software may not be called "OpenSSL"
30 * nor may "OpenSSL" appear in their names without prior written
31 * permission of the OpenSSL Project.
33 * 6. Redistributions of any form whatsoever must retain the following
35 * "This product includes software developed by the OpenSSL Project
36 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
39 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
41 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
42 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
47 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
49 * OF THE POSSIBILITY OF SUCH DAMAGE.
50 * ====================================================================
52 * This product includes cryptographic software written by Eric Young
53 * (eay@cryptsoft.com). This product includes software written by Tim
54 * Hudson (tjh@cryptsoft.com).
60 #include <openssl/asn1t.h>
61 #include <openssl/x509.h>
62 #include <openssl/ec.h>
64 #include <openssl/ecdsa.h>
65 #include <openssl/evp.h>
68 /* EC pkey context structure */
72 /* Key and paramgen group */
76 /* Duplicate key if custom cofactor needed */
79 signed char cofactor_mode;
80 /* KDF (if any) to use for ECDH */
82 /* Message digest to use for key derivation */
84 /* User key material */
85 unsigned char *kdf_ukm;
87 /* KDF output length */
92 static int pkey_ec_init(EVP_PKEY_CTX *ctx)
95 dctx = OPENSSL_malloc(sizeof(EC_PKEY_CTX));
98 dctx->gen_group = NULL;
101 dctx->cofactor_mode = -1;
103 dctx->kdf_type = EVP_PKEY_ECDH_KDF_NONE;
105 dctx->kdf_outlen = 0;
106 dctx->kdf_ukm = NULL;
107 dctx->kdf_ukmlen = 0;
114 static int pkey_ec_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
116 EC_PKEY_CTX *dctx, *sctx;
117 if (!pkey_ec_init(dst))
123 dctx->gen_group = EC_GROUP_dup(sctx->gen_group);
124 if (!dctx->gen_group)
131 dctx->co_key = EC_KEY_dup(sctx->co_key);
135 dctx->kdf_type = sctx->kdf_type;
136 dctx->kdf_md = sctx->kdf_md;
137 dctx->kdf_outlen = sctx->kdf_outlen;
140 dctx->kdf_ukm = BUF_memdup(sctx->kdf_ukm, sctx->kdf_ukmlen);
145 dctx->kdf_ukm = NULL;
146 dctx->kdf_ukmlen = sctx->kdf_ukmlen;
150 static void pkey_ec_cleanup(EVP_PKEY_CTX *ctx)
152 EC_PKEY_CTX *dctx = ctx->data;
156 EC_GROUP_free(dctx->gen_group);
158 EC_KEY_free(dctx->co_key);
160 OPENSSL_free(dctx->kdf_ukm);
165 static int pkey_ec_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen,
166 const unsigned char *tbs, size_t tbslen)
170 EC_PKEY_CTX *dctx = ctx->data;
171 EC_KEY *ec = ctx->pkey->pkey.ec;
175 *siglen = ECDSA_size(ec);
178 else if(*siglen < (size_t)ECDSA_size(ec))
180 ECerr(EC_F_PKEY_EC_SIGN, EC_R_BUFFER_TOO_SMALL);
185 type = EVP_MD_type(dctx->md);
190 ret = ECDSA_sign(type, tbs, tbslen, sig, &sltmp, ec);
194 *siglen = (size_t)sltmp;
198 static int pkey_ec_verify(EVP_PKEY_CTX *ctx,
199 const unsigned char *sig, size_t siglen,
200 const unsigned char *tbs, size_t tbslen)
203 EC_PKEY_CTX *dctx = ctx->data;
204 EC_KEY *ec = ctx->pkey->pkey.ec;
207 type = EVP_MD_type(dctx->md);
211 ret = ECDSA_verify(type, tbs, tbslen, sig, siglen, ec);
216 static int pkey_ec_derive(EVP_PKEY_CTX *ctx, unsigned char *key, size_t *keylen)
220 const EC_POINT *pubkey = NULL;
222 EC_PKEY_CTX *dctx = ctx->data;
223 if (!ctx->pkey || !ctx->peerkey)
225 ECerr(EC_F_PKEY_EC_DERIVE, EC_R_KEYS_NOT_SET);
229 eckey = dctx->co_key ? dctx->co_key : ctx->pkey->pkey.ec;
233 const EC_GROUP *group;
234 group = EC_KEY_get0_group(eckey);
235 *keylen = (EC_GROUP_get_degree(group) + 7)/8;
238 pubkey = EC_KEY_get0_public_key(ctx->peerkey->pkey.ec);
240 /* NB: unlike PKCS#3 DH, if *outlen is less than maximum size this is
241 * not an error, the result is truncated.
246 ret = ECDH_compute_key(key, outlen, pubkey, eckey, 0);
253 static int pkey_ec_kdf_derive(EVP_PKEY_CTX *ctx,
254 unsigned char *key, size_t *keylen)
256 EC_PKEY_CTX *dctx = ctx->data;
257 unsigned char *ktmp = NULL;
260 if (dctx->kdf_type == EVP_PKEY_ECDH_KDF_NONE)
261 return pkey_ec_derive(ctx, key, keylen);
264 *keylen = dctx->kdf_outlen;
267 if (*keylen != dctx->kdf_outlen)
269 if (!pkey_ec_derive(ctx, NULL, &ktmplen))
271 ktmp = OPENSSL_malloc(ktmplen);
274 if (!pkey_ec_derive(ctx, ktmp, &ktmplen))
277 if (!ECDH_KDF_X9_62(key, *keylen, ktmp, ktmplen,
278 dctx->kdf_ukm, dctx->kdf_ukmlen,
286 OPENSSL_cleanse(ktmp, ktmplen);
292 static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
294 EC_PKEY_CTX *dctx = ctx->data;
298 case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID:
299 group = EC_GROUP_new_by_curve_name(p1);
302 ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_CURVE);
306 EC_GROUP_free(dctx->gen_group);
307 dctx->gen_group = group;
310 case EVP_PKEY_CTRL_EC_PARAM_ENC:
311 if (!dctx->gen_group)
313 ECerr(EC_F_PKEY_EC_CTRL, EC_R_NO_PARAMETERS_SET);
316 EC_GROUP_set_asn1_flag(dctx->gen_group, p1);
319 case EVP_PKEY_CTRL_EC_ECDH_COFACTOR:
322 if (dctx->cofactor_mode != -1)
323 return dctx->cofactor_mode;
326 EC_KEY *ec_key = ctx->pkey->pkey.ec;
327 return EC_KEY_get_flags(ec_key) & EC_FLAG_COFACTOR_ECDH ? 1 : 0;
330 else if (p1 < -1 || p1 > 1)
332 dctx->cofactor_mode = p1;
335 EC_KEY *ec_key = ctx->pkey->pkey.ec;
338 /* If cofactor is 1 cofactor mode does nothing */
339 if (BN_is_one(&ec_key->group->cofactor))
343 dctx->co_key = EC_KEY_dup(ec_key);
348 EC_KEY_set_flags(dctx->co_key,
349 EC_FLAG_COFACTOR_ECDH);
351 EC_KEY_clear_flags(dctx->co_key,
352 EC_FLAG_COFACTOR_ECDH);
354 else if (dctx->co_key)
356 EC_KEY_free(dctx->co_key);
361 case EVP_PKEY_CTRL_EC_KDF_TYPE:
363 return dctx->kdf_type;
364 if (p1 != EVP_PKEY_ECDH_KDF_NONE &&
365 p1 != EVP_PKEY_ECDH_KDF_X9_62)
370 case EVP_PKEY_CTRL_EC_KDF_MD:
374 case EVP_PKEY_CTRL_GET_EC_KDF_MD:
375 *(const EVP_MD **)p2 = dctx->kdf_md;
378 case EVP_PKEY_CTRL_EC_KDF_OUTLEN:
381 dctx->kdf_outlen = (size_t)p1;
384 case EVP_PKEY_CTRL_GET_EC_KDF_OUTLEN:
385 *(int *)p2 = dctx->kdf_outlen;
388 case EVP_PKEY_CTRL_EC_KDF_UKM:
390 OPENSSL_free(dctx->kdf_ukm);
393 dctx->kdf_ukmlen = p1;
395 dctx->kdf_ukmlen = 0;
398 case EVP_PKEY_CTRL_GET_EC_KDF_UKM:
399 *(unsigned char **)p2 = dctx->kdf_ukm;
400 return dctx->kdf_ukmlen;
402 case EVP_PKEY_CTRL_MD:
403 if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
404 EVP_MD_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
405 EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
406 EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
407 EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
408 EVP_MD_type((const EVP_MD *)p2) != NID_sha512)
410 ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_DIGEST_TYPE);
416 case EVP_PKEY_CTRL_GET_MD:
417 *(const EVP_MD **)p2 = dctx->md;
420 case EVP_PKEY_CTRL_PEER_KEY:
421 /* Default behaviour is OK */
422 case EVP_PKEY_CTRL_DIGESTINIT:
423 case EVP_PKEY_CTRL_PKCS7_SIGN:
424 case EVP_PKEY_CTRL_CMS_SIGN:
433 static int pkey_ec_ctrl_str(EVP_PKEY_CTX *ctx,
434 const char *type, const char *value)
436 if (!strcmp(type, "ec_paramgen_curve"))
439 nid = EC_curve_nist2nid(value);
440 if (nid == NID_undef)
441 nid = OBJ_sn2nid(value);
442 if (nid == NID_undef)
443 nid = OBJ_ln2nid(value);
444 if (nid == NID_undef)
446 ECerr(EC_F_PKEY_EC_CTRL_STR, EC_R_INVALID_CURVE);
449 return EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx, nid);
451 else if (!strcmp(type, "ec_param_enc"))
454 if (!strcmp(value, "explicit"))
456 else if (!strcmp(value, "named_curve"))
457 param_enc = OPENSSL_EC_NAMED_CURVE;
460 return EVP_PKEY_CTX_set_ec_param_enc(ctx, param_enc);
462 else if (!strcmp(type, "ecdh_kdf_md"))
465 if (!(md = EVP_get_digestbyname(value)))
467 ECerr(EC_F_PKEY_EC_CTRL_STR, EC_R_INVALID_DIGEST);
470 return EVP_PKEY_CTX_set_ecdh_kdf_md(ctx, md);
472 else if (!strcmp(type, "ecdh_cofactor_mode"))
475 co_mode = atoi(value);
476 return EVP_PKEY_CTX_set_ecdh_cofactor_mode(ctx, co_mode);
482 static int pkey_ec_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
485 EC_PKEY_CTX *dctx = ctx->data;
487 if (dctx->gen_group == NULL)
489 ECerr(EC_F_PKEY_EC_PARAMGEN, EC_R_NO_PARAMETERS_SET);
495 ret = EC_KEY_set_group(ec, dctx->gen_group);
497 EVP_PKEY_assign_EC_KEY(pkey, ec);
503 static int pkey_ec_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
506 EC_PKEY_CTX *dctx = ctx->data;
507 if (ctx->pkey == NULL && dctx->gen_group == NULL)
509 ECerr(EC_F_PKEY_EC_KEYGEN, EC_R_NO_PARAMETERS_SET);
515 EVP_PKEY_assign_EC_KEY(pkey, ec);
518 /* Note: if error return, pkey is freed by parent routine */
519 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
524 if (!EC_KEY_set_group(ec, dctx->gen_group))
527 return EC_KEY_generate_key(pkey->pkey.ec);
530 const EVP_PKEY_METHOD ec_pkey_meth =