1 /* Written by Dr Stephen N Henson (steve (at) openssl.org) for the OpenSSL 2 * project 2006. 3 */ 4 /* ==================================================================== 5 * Copyright (c) 2006 The OpenSSL Project. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 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 17 * distribution. 18 * 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/)" 23 * 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 (at) OpenSSL.org. 28 * 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. 32 * 33 * 6. Redistributions of any form whatsoever must retain the following 34 * acknowledgment: 35 * "This product includes software developed by the OpenSSL Project 36 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 37 * 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 * ==================================================================== 51 * 52 * This product includes cryptographic software written by Eric Young 53 * (eay (at) cryptsoft.com). This product includes software written by Tim 54 * Hudson (tjh (at) cryptsoft.com). 55 * 56 */ 57 58 #include <stdio.h> 59 #include "cryptlib.h" 60 #include <openssl/asn1t.h> 61 #include <openssl/x509.h> 62 #include <openssl/ec.h> 63 #include <openssl/ecdsa.h> 64 #include <openssl/evp.h> 65 #include "evp_locl.h" 66 67 /* EC pkey context structure */ 68 69 typedef struct 70 { 71 /* Key and paramgen group */ 72 EC_GROUP *gen_group; 73 /* message digest */ 74 const EVP_MD *md; 75 } EC_PKEY_CTX; 76 77 static int pkey_ec_init(EVP_PKEY_CTX *ctx) 78 { 79 EC_PKEY_CTX *dctx; 80 dctx = OPENSSL_malloc(sizeof(EC_PKEY_CTX)); 81 if (!dctx) 82 return 0; 83 dctx->gen_group = NULL; 84 dctx->md = NULL; 85 86 ctx->data = dctx; 87 88 return 1; 89 } 90 91 static int pkey_ec_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src) 92 { 93 EC_PKEY_CTX *dctx, *sctx; 94 if (!pkey_ec_init(dst)) 95 return 0; 96 sctx = src->data; 97 dctx = dst->data; 98 if (sctx->gen_group) 99 { 100 dctx->gen_group = EC_GROUP_dup(sctx->gen_group); 101 if (!dctx->gen_group) 102 return 0; 103 } 104 dctx->md = sctx->md; 105 return 1; 106 } 107 108 static void pkey_ec_cleanup(EVP_PKEY_CTX *ctx) 109 { 110 EC_PKEY_CTX *dctx = ctx->data; 111 if (dctx) 112 { 113 if (dctx->gen_group) 114 EC_GROUP_free(dctx->gen_group); 115 OPENSSL_free(dctx); 116 } 117 } 118 119 static int pkey_ec_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *siglen, 120 const unsigned char *tbs, size_t tbslen) 121 { 122 int ret, type; 123 unsigned int sltmp; 124 EC_PKEY_CTX *dctx = ctx->data; 125 EC_KEY *ec = ctx->pkey->pkey.ec; 126 127 if (!sig) 128 { 129 *siglen = ECDSA_size(ec); 130 return 1; 131 } 132 else if(*siglen < (size_t)ECDSA_size(ec)) 133 { 134 ECerr(EC_F_PKEY_EC_SIGN, EC_R_BUFFER_TOO_SMALL); 135 return 0; 136 } 137 138 if (dctx->md) 139 type = EVP_MD_type(dctx->md); 140 else 141 type = NID_sha1; 142 143 144 ret = ECDSA_sign(type, tbs, tbslen, sig, &sltmp, ec); 145 146 if (ret <= 0) 147 return ret; 148 *siglen = (size_t)sltmp; 149 return 1; 150 } 151 152 static int pkey_ec_verify(EVP_PKEY_CTX *ctx, 153 const unsigned char *sig, size_t siglen, 154 const unsigned char *tbs, size_t tbslen) 155 { 156 int ret, type; 157 EC_PKEY_CTX *dctx = ctx->data; 158 EC_KEY *ec = ctx->pkey->pkey.ec; 159 160 if (dctx->md) 161 type = EVP_MD_type(dctx->md); 162 else 163 type = NID_sha1; 164 165 ret = ECDSA_verify(type, tbs, tbslen, sig, siglen, ec); 166 167 return ret; 168 } 169 170 static int pkey_ec_derive(EVP_PKEY_CTX *ctx, unsigned char *key, size_t *keylen) 171 { 172 int ret; 173 size_t outlen; 174 const EC_POINT *pubkey = NULL; 175 if (!ctx->pkey || !ctx->peerkey) 176 { 177 ECerr(EC_F_PKEY_EC_DERIVE, EC_R_KEYS_NOT_SET); 178 return 0; 179 } 180 181 if (!key) 182 { 183 const EC_GROUP *group; 184 group = EC_KEY_get0_group(ctx->pkey->pkey.ec); 185 *keylen = (EC_GROUP_get_degree(group) + 7)/8; 186 return 1; 187 } 188 189 pubkey = EC_KEY_get0_public_key(ctx->peerkey->pkey.ec); 190 191 /* NB: unlike PKS#3 DH, if *outlen is less than maximum size this is 192 * not an error, the result is truncated. 193 */ 194 195 outlen = *keylen; 196 197 ret = ECDH_compute_key(key, outlen, pubkey, ctx->pkey->pkey.ec, 0); 198 if (ret < 0) 199 return ret; 200 *keylen = ret; 201 return 1; 202 } 203 204 static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2) 205 { 206 EC_PKEY_CTX *dctx = ctx->data; 207 EC_GROUP *group; 208 switch (type) 209 { 210 case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID: 211 group = EC_GROUP_new_by_curve_name(p1); 212 if (group == NULL) 213 { 214 ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_CURVE); 215 return 0; 216 } 217 if (dctx->gen_group) 218 EC_GROUP_free(dctx->gen_group); 219 dctx->gen_group = group; 220 return 1; 221 222 case EVP_PKEY_CTRL_MD: 223 if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 && 224 EVP_MD_type((const EVP_MD *)p2) != NID_sha224 && 225 EVP_MD_type((const EVP_MD *)p2) != NID_sha256 && 226 EVP_MD_type((const EVP_MD *)p2) != NID_sha384 && 227 EVP_MD_type((const EVP_MD *)p2) != NID_sha512) 228 { 229 ECerr(EC_F_PKEY_EC_CTRL, EC_R_INVALID_DIGEST_TYPE); 230 return 0; 231 } 232 dctx->md = p2; 233 return 1; 234 235 case EVP_PKEY_CTRL_PEER_KEY: 236 /* Default behaviour is OK */ 237 case EVP_PKEY_CTRL_DIGESTINIT: 238 case EVP_PKEY_CTRL_PKCS7_SIGN: 239 case EVP_PKEY_CTRL_CMS_SIGN: 240 return 1; 241 242 default: 243 return -2; 244 245 } 246 } 247 248 static int pkey_ec_ctrl_str(EVP_PKEY_CTX *ctx, 249 const char *type, const char *value) 250 { 251 if (!strcmp(type, "ec_paramgen_curve")) 252 { 253 int nid; 254 nid = OBJ_sn2nid(value); 255 if (nid == NID_undef) 256 nid = OBJ_ln2nid(value); 257 if (nid == NID_undef) 258 { 259 ECerr(EC_F_PKEY_EC_CTRL_STR, EC_R_INVALID_CURVE); 260 return 0; 261 } 262 return EVP_PKEY_CTX_set_ec_paramgen_curve_nid(ctx, nid); 263 } 264 return -2; 265 } 266 267 static int pkey_ec_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) 268 { 269 EC_KEY *ec = NULL; 270 EC_PKEY_CTX *dctx = ctx->data; 271 int ret = 0; 272 if (dctx->gen_group == NULL) 273 { 274 ECerr(EC_F_PKEY_EC_PARAMGEN, EC_R_NO_PARAMETERS_SET); 275 return 0; 276 } 277 ec = EC_KEY_new(); 278 if (!ec) 279 return 0; 280 ret = EC_KEY_set_group(ec, dctx->gen_group); 281 if (ret) 282 EVP_PKEY_assign_EC_KEY(pkey, ec); 283 else 284 EC_KEY_free(ec); 285 return ret; 286 } 287 288 static int pkey_ec_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) 289 { 290 EC_KEY *ec = NULL; 291 if (ctx->pkey == NULL) 292 { 293 ECerr(EC_F_PKEY_EC_KEYGEN, EC_R_NO_PARAMETERS_SET); 294 return 0; 295 } 296 ec = EC_KEY_new(); 297 if (!ec) 298 return 0; 299 EVP_PKEY_assign_EC_KEY(pkey, ec); 300 /* Note: if error return, pkey is freed by parent routine */ 301 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey)) 302 return 0; 303 return EC_KEY_generate_key(pkey->pkey.ec); 304 } 305 306 const EVP_PKEY_METHOD ec_pkey_meth = 307 { 308 EVP_PKEY_EC, 309 0, 310 pkey_ec_init, 311 pkey_ec_copy, 312 pkey_ec_cleanup, 313 314 0, 315 pkey_ec_paramgen, 316 317 0, 318 pkey_ec_keygen, 319 320 0, 321 pkey_ec_sign, 322 323 0, 324 pkey_ec_verify, 325 326 0,0, 327 328 0,0,0,0, 329 330 0,0, 331 332 0,0, 333 334 0, 335 pkey_ec_derive, 336 337 pkey_ec_ctrl, 338 pkey_ec_ctrl_str 339 340 }; 341
