1 /* $OpenBSD: dsa_pmeth.c,v 1.21 2024/10/19 14:39:44 tb Exp $ */ 2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 3 * project 2006. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2006 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * licensing@OpenSSL.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@cryptsoft.com). 56 * 57 */ 58 59 #include <limits.h> 60 #include <stdio.h> 61 #include <stdlib.h> 62 #include <string.h> 63 64 #include <openssl/asn1t.h> 65 #include <openssl/bn.h> 66 #include <openssl/err.h> 67 #include <openssl/evp.h> 68 #include <openssl/x509.h> 69 70 #include "bn_local.h" 71 #include "dsa_local.h" 72 #include "evp_local.h" 73 74 /* DSA pkey context structure */ 75 76 typedef struct { 77 /* Parameter gen parameters */ 78 int nbits; /* size of p in bits (default: 1024) */ 79 int qbits; /* size of q in bits (default: 160) */ 80 const EVP_MD *pmd; /* MD for parameter generation */ 81 /* Keygen callback info */ 82 int gentmp[2]; 83 /* message digest */ 84 const EVP_MD *md; /* MD for the signature */ 85 } DSA_PKEY_CTX; 86 87 static int 88 pkey_dsa_init(EVP_PKEY_CTX *ctx) 89 { 90 DSA_PKEY_CTX *dctx; 91 92 dctx = malloc(sizeof(DSA_PKEY_CTX)); 93 if (!dctx) 94 return 0; 95 dctx->nbits = 1024; 96 dctx->qbits = 160; 97 dctx->pmd = NULL; 98 dctx->md = NULL; 99 100 ctx->data = dctx; 101 ctx->keygen_info = dctx->gentmp; 102 ctx->keygen_info_count = 2; 103 104 return 1; 105 } 106 107 static int 108 pkey_dsa_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src) 109 { 110 DSA_PKEY_CTX *dctx, *sctx; 111 112 if (!pkey_dsa_init(dst)) 113 return 0; 114 sctx = src->data; 115 dctx = dst->data; 116 dctx->nbits = sctx->nbits; 117 dctx->qbits = sctx->qbits; 118 dctx->pmd = sctx->pmd; 119 dctx->md = sctx->md; 120 return 1; 121 } 122 123 static void 124 pkey_dsa_cleanup(EVP_PKEY_CTX *ctx) 125 { 126 DSA_PKEY_CTX *dctx = ctx->data; 127 128 free(dctx); 129 } 130 131 static int 132 pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig, size_t *out_siglen, 133 const unsigned char *tbs, size_t tbslen) 134 { 135 DSA *dsa = ctx->pkey->pkey.dsa; 136 DSA_PKEY_CTX *dctx = ctx->data; 137 unsigned int siglen; 138 139 *out_siglen = 0; 140 141 if (tbslen > INT_MAX) 142 return 0; 143 144 if (dctx->md != NULL) { 145 if (tbslen != EVP_MD_size(dctx->md)) 146 return 0; 147 } 148 149 if (!DSA_sign(0, tbs, tbslen, sig, &siglen, dsa)) 150 return 0; 151 152 *out_siglen = siglen; 153 154 return 1; 155 } 156 157 static int 158 pkey_dsa_verify(EVP_PKEY_CTX *ctx, const unsigned char *sig, size_t siglen, 159 const unsigned char *tbs, size_t tbslen) 160 { 161 DSA *dsa = ctx->pkey->pkey.dsa; 162 DSA_PKEY_CTX *dctx = ctx->data; 163 164 if (tbslen > INT_MAX || siglen > INT_MAX) 165 return 0; 166 167 if (dctx->md != NULL) { 168 if (tbslen != EVP_MD_size(dctx->md)) 169 return 0; 170 } 171 172 return DSA_verify(0, tbs, tbslen, sig, siglen, dsa); 173 } 174 175 static int 176 pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2) 177 { 178 DSA_PKEY_CTX *dctx = ctx->data; 179 180 switch (type) { 181 case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS: 182 if (p1 < 256) 183 return -2; 184 dctx->nbits = p1; 185 return 1; 186 187 case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS: 188 if (p1 != 160 && p1 != 224 && p1 && p1 != 256) 189 return -2; 190 dctx->qbits = p1; 191 return 1; 192 193 case EVP_PKEY_CTRL_DSA_PARAMGEN_MD: 194 switch (EVP_MD_type((const EVP_MD *)p2)) { 195 case NID_sha1: 196 case NID_sha224: 197 case NID_sha256: 198 break; 199 default: 200 DSAerror(DSA_R_INVALID_DIGEST_TYPE); 201 return 0; 202 } 203 dctx->md = p2; 204 return 1; 205 206 case EVP_PKEY_CTRL_MD: 207 /* ANSI X9.57 and NIST CSOR. */ 208 switch (EVP_MD_type(p2)) { 209 case NID_sha1: 210 case NID_dsa: 211 case NID_dsaWithSHA: 212 case NID_sha224: 213 case NID_sha256: 214 case NID_sha384: 215 case NID_sha512: 216 case NID_sha3_224: 217 case NID_sha3_256: 218 case NID_sha3_384: 219 case NID_sha3_512: 220 break; 221 default: 222 DSAerror(DSA_R_INVALID_DIGEST_TYPE); 223 return 0; 224 } 225 dctx->md = p2; 226 return 1; 227 228 case EVP_PKEY_CTRL_GET_MD: 229 *(const EVP_MD **)p2 = dctx->md; 230 return 1; 231 232 case EVP_PKEY_CTRL_DIGESTINIT: 233 case EVP_PKEY_CTRL_PKCS7_SIGN: 234 case EVP_PKEY_CTRL_CMS_SIGN: 235 return 1; 236 237 case EVP_PKEY_CTRL_PEER_KEY: 238 DSAerror(EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE); 239 return -2; 240 default: 241 return -2; 242 } 243 } 244 245 static int 246 pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx, const char *type, const char *value) 247 { 248 const char *errstr; 249 250 if (!strcmp(type, "dsa_paramgen_bits")) { 251 int nbits; 252 253 nbits = strtonum(value, INT_MIN, INT_MAX, &errstr); 254 if (errstr != NULL) 255 return -2; 256 return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits); 257 } else if (!strcmp(type, "dsa_paramgen_q_bits")) { 258 int qbits; 259 260 qbits = strtonum(value, INT_MIN, INT_MAX, &errstr); 261 if (errstr != NULL) 262 return -2; 263 return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DSA, 264 EVP_PKEY_OP_PARAMGEN, EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS, 265 qbits, NULL); 266 } else if (!strcmp(type, "dsa_paramgen_md")) { 267 return EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DSA, 268 EVP_PKEY_OP_PARAMGEN, EVP_PKEY_CTRL_DSA_PARAMGEN_MD, 0, 269 (void *)EVP_get_digestbyname(value)); 270 } 271 272 return -2; 273 } 274 275 static int 276 pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) 277 { 278 DSA *dsa; 279 DSA_PKEY_CTX *dctx = ctx->data; 280 BN_GENCB *pcb = NULL; 281 BN_GENCB cb = {0}; 282 int ret = 0; 283 284 if ((dsa = DSA_new()) == NULL) 285 goto err; 286 if (ctx->pkey_gencb != NULL) { 287 pcb = &cb; 288 evp_pkey_set_cb_translate(pcb, ctx); 289 } 290 if (!dsa_builtin_paramgen(dsa, dctx->nbits, dctx->qbits, dctx->pmd, 291 NULL, 0, NULL, NULL, NULL, pcb)) 292 goto err; 293 if (!EVP_PKEY_assign_DSA(pkey, dsa)) 294 goto err; 295 dsa = NULL; 296 297 ret = 1; 298 299 err: 300 DSA_free(dsa); 301 302 return ret; 303 } 304 305 static int 306 pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) 307 { 308 DSA *dsa = NULL; 309 int ret = 0; 310 311 if (ctx->pkey == NULL) { 312 DSAerror(DSA_R_NO_PARAMETERS_SET); 313 goto err; 314 } 315 if ((dsa = DSA_new()) == NULL) 316 goto err; 317 if (!EVP_PKEY_set1_DSA(pkey, dsa)) 318 goto err; 319 320 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey)) 321 goto err; 322 if (!DSA_generate_key(dsa)) 323 goto err; 324 325 ret = 1; 326 327 err: 328 DSA_free(dsa); 329 330 return ret; 331 } 332 333 const EVP_PKEY_METHOD dsa_pkey_meth = { 334 .pkey_id = EVP_PKEY_DSA, 335 .flags = EVP_PKEY_FLAG_AUTOARGLEN, 336 337 .init = pkey_dsa_init, 338 .copy = pkey_dsa_copy, 339 .cleanup = pkey_dsa_cleanup, 340 341 .paramgen = pkey_dsa_paramgen, 342 343 .keygen = pkey_dsa_keygen, 344 345 .sign = pkey_dsa_sign, 346 347 .verify = pkey_dsa_verify, 348 349 .ctrl = pkey_dsa_ctrl, 350 .ctrl_str = pkey_dsa_ctrl_str 351 }; 352