1 /* Copyright (C) 1995-1998 Eric Young (eay (at) cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay (at) cryptsoft.com). 6 * The implementation was written so as to conform with Netscapes SSL. 7 * 8 * This library is free for commercial and non-commercial use as long as 9 * the following conditions are aheared to. The following conditions 10 * apply to all code found in this distribution, be it the RC4, RSA, 11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 12 * included with this distribution is covered by the same copyright terms 13 * except that the holder is Tim Hudson (tjh (at) cryptsoft.com). 14 * 15 * Copyright remains Eric Young's, and as such any Copyright notices in 16 * the code are not to be removed. 17 * If this package is used in a product, Eric Young should be given attribution 18 * as the author of the parts of the library used. 19 * This can be in the form of a textual message at program startup or 20 * in documentation (online or textual) provided with the package. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 1. Redistributions of source code must retain the copyright 26 * notice, this list of conditions and the following disclaimer. 27 * 2. Redistributions in binary form must reproduce the above copyright 28 * notice, this list of conditions and the following disclaimer in the 29 * documentation and/or other materials provided with the distribution. 30 * 3. All advertising materials mentioning features or use of this software 31 * must display the following acknowledgement: 32 * "This product includes cryptographic software written by 33 * Eric Young (eay (at) cryptsoft.com)" 34 * The word 'cryptographic' can be left out if the rouines from the library 35 * being used are not cryptographic related :-). 36 * 4. If you include any Windows specific code (or a derivative thereof) from 37 * the apps directory (application code) you must include an acknowledgement: 38 * "This product includes software written by Tim Hudson (tjh (at) cryptsoft.com)" 39 * 40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * The licence and distribution terms for any publically available version or 53 * derivative of this code cannot be changed. i.e. this code cannot simply be 54 * copied and put under another distribution licence 55 * [including the GNU Public Licence.] 56 * 57 * The DSS routines are based on patches supplied by 58 * Steven Schoch <schoch (at) sheba.arc.nasa.gov>. */ 59 60 #include <openssl/dsa.h> 61 62 #include <openssl/asn1.h> 63 #include <openssl/dh.h> 64 #include <openssl/engine.h> 65 #include <openssl/err.h> 66 #include <openssl/ex_data.h> 67 #include <openssl/mem.h> 68 69 #include "internal.h" 70 71 extern const DSA_METHOD DSA_default_method; 72 73 DSA *DSA_new(void) { return DSA_new_method(NULL); } 74 75 DSA *DSA_new_method(const ENGINE *engine) { 76 DSA *dsa = (DSA *)OPENSSL_malloc(sizeof(DSA)); 77 if (dsa == NULL) { 78 OPENSSL_PUT_ERROR(DSA, DSA_new_method, ERR_R_MALLOC_FAILURE); 79 return NULL; 80 } 81 82 memset(dsa, 0, sizeof(DSA)); 83 84 if (engine) { 85 dsa->meth = ENGINE_get_DSA_method(engine); 86 } 87 88 if (dsa->meth == NULL) { 89 dsa->meth = (DSA_METHOD*) &DSA_default_method; 90 } 91 METHOD_ref(dsa->meth); 92 93 dsa->write_params = 1; 94 dsa->references = 1; 95 96 if (!CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, dsa, &dsa->ex_data)) { 97 METHOD_unref(dsa->meth); 98 OPENSSL_free(dsa); 99 return NULL; 100 } 101 102 if (dsa->meth->init && !dsa->meth->init(dsa)) { 103 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, dsa, &dsa->ex_data); 104 METHOD_unref(dsa->meth); 105 OPENSSL_free(dsa); 106 return NULL; 107 } 108 109 return dsa; 110 } 111 112 void DSA_free(DSA *dsa) { 113 if (dsa == NULL) { 114 return; 115 } 116 117 if (CRYPTO_add(&dsa->references, -1, CRYPTO_LOCK_DSA) > 0) { 118 return; 119 } 120 121 if (dsa->meth->finish) { 122 dsa->meth->finish(dsa); 123 } 124 METHOD_unref(dsa->meth); 125 126 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, dsa, &dsa->ex_data); 127 128 if (dsa->p != NULL) 129 BN_clear_free(dsa->p); 130 if (dsa->q != NULL) 131 BN_clear_free(dsa->q); 132 if (dsa->g != NULL) 133 BN_clear_free(dsa->g); 134 if (dsa->pub_key != NULL) 135 BN_clear_free(dsa->pub_key); 136 if (dsa->priv_key != NULL) 137 BN_clear_free(dsa->priv_key); 138 if (dsa->kinv != NULL) 139 BN_clear_free(dsa->kinv); 140 if (dsa->r != NULL) 141 BN_clear_free(dsa->r); 142 OPENSSL_free(dsa); 143 } 144 145 int DSA_up_ref(DSA *dsa) { 146 CRYPTO_add(&dsa->references, 1, CRYPTO_LOCK_DSA); 147 return 1; 148 } 149 150 int DSA_generate_parameters_ex(DSA *dsa, unsigned bits, const uint8_t *seed_in, 151 size_t seed_len, int *out_counter, 152 unsigned long *out_h, BN_GENCB *cb) { 153 if (dsa->meth->generate_parameters) { 154 return dsa->meth->generate_parameters(dsa, bits, seed_in, seed_len, 155 out_counter, out_h, cb); 156 } 157 return DSA_default_method.generate_parameters(dsa, bits, seed_in, seed_len, 158 out_counter, out_h, cb); 159 } 160 161 int DSA_generate_key(DSA *dsa) { 162 if (dsa->meth->keygen) { 163 return dsa->meth->keygen(dsa); 164 } 165 return DSA_default_method.keygen(dsa); 166 } 167 168 DSA_SIG *DSA_SIG_new(void) { 169 DSA_SIG *sig; 170 sig = OPENSSL_malloc(sizeof(DSA_SIG)); 171 if (!sig) { 172 return NULL; 173 } 174 sig->r = NULL; 175 sig->s = NULL; 176 return sig; 177 } 178 179 void DSA_SIG_free(DSA_SIG *sig) { 180 if (!sig) { 181 return; 182 } 183 184 if (sig->r) { 185 BN_free(sig->r); 186 } 187 if (sig->s) { 188 BN_free(sig->s); 189 } 190 OPENSSL_free(sig); 191 } 192 193 DSA_SIG *DSA_do_sign(const uint8_t *digest, size_t digest_len, DSA *dsa) { 194 if (dsa->meth->sign) { 195 return dsa->meth->sign(digest, digest_len, dsa); 196 } 197 return DSA_default_method.sign(digest, digest_len, dsa); 198 } 199 200 int DSA_do_verify(const uint8_t *digest, size_t digest_len, DSA_SIG *sig, 201 const DSA *dsa) { 202 int valid, ret; 203 204 if (dsa->meth->verify) { 205 ret = dsa->meth->verify(&valid, digest, digest_len, sig, dsa); 206 } else { 207 ret = DSA_default_method.verify(&valid, digest, digest_len, sig, dsa); 208 } 209 210 if (!ret) { 211 return -1; 212 } else if (!valid) { 213 return 0; 214 } 215 return 1; 216 } 217 218 int DSA_do_check_signature(int *out_valid, const uint8_t *digest, 219 size_t digest_len, DSA_SIG *sig, const DSA *dsa) { 220 if (dsa->meth->verify) { 221 return dsa->meth->verify(out_valid, digest, digest_len, sig, dsa); 222 } 223 224 return DSA_default_method.verify(out_valid, digest, digest_len, sig, dsa); 225 } 226 227 int DSA_sign(int type, const uint8_t *digest, size_t digest_len, 228 uint8_t *out_sig, unsigned int *out_siglen, DSA *dsa) { 229 DSA_SIG *s; 230 231 s = DSA_do_sign(digest, digest_len, dsa); 232 if (s == NULL) { 233 *out_siglen = 0; 234 return 0; 235 } 236 237 *out_siglen = i2d_DSA_SIG(s, &out_sig); 238 DSA_SIG_free(s); 239 return 1; 240 } 241 242 int DSA_verify(int type, const uint8_t *digest, size_t digest_len, 243 const uint8_t *sig, size_t sig_len, const DSA *dsa) { 244 DSA_SIG *s = NULL; 245 int ret = -1, valid; 246 247 s = DSA_SIG_new(); 248 if (s == NULL) { 249 goto err; 250 } 251 252 if (d2i_DSA_SIG(&s, &sig, sig_len) == NULL) { 253 goto err; 254 } 255 256 if (!DSA_do_check_signature(&valid, digest, digest_len, s, dsa)) { 257 goto err; 258 } 259 260 ret = valid; 261 262 err: 263 if (s) { 264 DSA_SIG_free(s); 265 } 266 return ret; 267 } 268 269 int DSA_check_signature(int *out_valid, const uint8_t *digest, 270 size_t digest_len, const uint8_t *sig, size_t sig_len, 271 const DSA *dsa) { 272 DSA_SIG *s = NULL; 273 int ret = 0; 274 275 s = DSA_SIG_new(); 276 if (s == NULL) { 277 goto err; 278 } 279 280 if (d2i_DSA_SIG(&s, &sig, sig_len) == NULL) { 281 goto err; 282 } 283 284 ret = DSA_do_check_signature(out_valid, digest, digest_len, s, dsa); 285 286 err: 287 if (s) { 288 DSA_SIG_free(s); 289 } 290 return ret; 291 } 292 293 int DSA_size(const DSA *dsa) { 294 int ret, i; 295 ASN1_INTEGER bs; 296 unsigned char buf[4]; /* 4 bytes looks really small. 297 However, i2d_ASN1_INTEGER() will not look 298 beyond the first byte, as long as the second 299 parameter is NULL. */ 300 301 i = BN_num_bits(dsa->q); 302 bs.length = (i + 7) / 8; 303 bs.data = buf; 304 bs.type = V_ASN1_INTEGER; 305 /* If the top bit is set the asn1 encoding is 1 larger. */ 306 buf[0] = 0xff; 307 308 i = i2d_ASN1_INTEGER(&bs, NULL); 309 i += i; /* r and s */ 310 ret = ASN1_object_size(1, i, V_ASN1_SEQUENCE); 311 return ret; 312 } 313 314 int DSA_sign_setup(const DSA *dsa, BN_CTX *ctx, BIGNUM **out_kinv, 315 BIGNUM **out_r) { 316 if (dsa->meth->sign_setup) { 317 return dsa->meth->sign_setup(dsa, ctx, out_kinv, out_r, NULL, 0); 318 } 319 320 return DSA_default_method.sign_setup(dsa, ctx, out_kinv, out_r, NULL, 0); 321 } 322 323 int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 324 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) { 325 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DSA, argl, argp, new_func, 326 dup_func, free_func); 327 } 328 329 int DSA_set_ex_data(DSA *d, int idx, void *arg) { 330 return CRYPTO_set_ex_data(&d->ex_data, idx, arg); 331 } 332 333 void *DSA_get_ex_data(const DSA *d, int idx) { 334 return CRYPTO_get_ex_data(&d->ex_data, idx); 335 } 336 337 DH *DSA_dup_DH(const DSA *r) { 338 DH *ret = NULL; 339 340 if (r == NULL) { 341 goto err; 342 } 343 ret = DH_new(); 344 if (ret == NULL) { 345 goto err; 346 } 347 if (r->q != NULL) { 348 ret->priv_length = BN_num_bits(r->q); 349 if ((ret->q = BN_dup(r->q)) == NULL) { 350 goto err; 351 } 352 } 353 if ((r->p != NULL && (ret->p = BN_dup(r->p)) == NULL) || 354 (r->g != NULL && (ret->g = BN_dup(r->g)) == NULL) || 355 (r->pub_key != NULL && (ret->pub_key = BN_dup(r->pub_key)) == NULL) || 356 (r->priv_key != NULL && (ret->priv_key = BN_dup(r->priv_key)) == NULL)) { 357 goto err; 358 } 359 360 return ret; 361 362 err: 363 if (ret != NULL) { 364 DH_free(ret); 365 } 366 return NULL; 367 } 368
