dsa_lib.c revision 392aa7cc7d2b122614c5393c3e357da07fd07af3
1/* crypto/dsa/dsa_lib.c */ 2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 3 * All rights reserved. 4 * 5 * This package is an SSL implementation written 6 * by Eric Young (eay@cryptsoft.com). 7 * The implementation was written so as to conform with Netscapes SSL. 8 * 9 * This library is free for commercial and non-commercial use as long as 10 * the following conditions are aheared to. The following conditions 11 * apply to all code found in this distribution, be it the RC4, RSA, 12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation 13 * included with this distribution is covered by the same copyright terms 14 * except that the holder is Tim Hudson (tjh@cryptsoft.com). 15 * 16 * Copyright remains Eric Young's, and as such any Copyright notices in 17 * the code are not to be removed. 18 * If this package is used in a product, Eric Young should be given attribution 19 * as the author of the parts of the library used. 20 * This can be in the form of a textual message at program startup or 21 * in documentation (online or textual) provided with the package. 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 3. All advertising materials mentioning features or use of this software 32 * must display the following acknowledgement: 33 * "This product includes cryptographic software written by 34 * Eric Young (eay@cryptsoft.com)" 35 * The word 'cryptographic' can be left out if the rouines from the library 36 * being used are not cryptographic related :-). 37 * 4. If you include any Windows specific code (or a derivative thereof) from 38 * the apps directory (application code) you must include an acknowledgement: 39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" 40 * 41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND 42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 51 * SUCH DAMAGE. 52 * 53 * The licence and distribution terms for any publically available version or 54 * derivative of this code cannot be changed. i.e. this code cannot simply be 55 * copied and put under another distribution licence 56 * [including the GNU Public Licence.] 57 */ 58 59/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */ 60 61#include <stdio.h> 62#include "cryptlib.h" 63#include <openssl/bn.h> 64#include <openssl/dsa.h> 65#include <openssl/asn1.h> 66#ifndef OPENSSL_NO_ENGINE 67#include <openssl/engine.h> 68#endif 69#ifndef OPENSSL_NO_DH 70#include <openssl/dh.h> 71#endif 72 73#ifdef OPENSSL_FIPS 74#include <openssl/fips.h> 75#endif 76 77const char DSA_version[]="DSA" OPENSSL_VERSION_PTEXT; 78 79static const DSA_METHOD *default_DSA_method = NULL; 80 81void DSA_set_default_method(const DSA_METHOD *meth) 82 { 83 default_DSA_method = meth; 84 } 85 86const DSA_METHOD *DSA_get_default_method(void) 87 { 88 if(!default_DSA_method) 89 { 90#ifdef OPENSSL_FIPS 91 if (FIPS_mode()) 92 return FIPS_dsa_openssl(); 93 else 94 return DSA_OpenSSL(); 95#else 96 default_DSA_method = DSA_OpenSSL(); 97#endif 98 } 99 return default_DSA_method; 100 } 101 102DSA *DSA_new(void) 103 { 104 return DSA_new_method(NULL); 105 } 106 107int DSA_set_method(DSA *dsa, const DSA_METHOD *meth) 108 { 109 /* NB: The caller is specifically setting a method, so it's not up to us 110 * to deal with which ENGINE it comes from. */ 111 const DSA_METHOD *mtmp; 112 mtmp = dsa->meth; 113 if (mtmp->finish) mtmp->finish(dsa); 114#ifndef OPENSSL_NO_ENGINE 115 if (dsa->engine) 116 { 117 ENGINE_finish(dsa->engine); 118 dsa->engine = NULL; 119 } 120#endif 121 dsa->meth = meth; 122 if (meth->init) meth->init(dsa); 123 return 1; 124 } 125 126DSA *DSA_new_method(ENGINE *engine) 127 { 128 DSA *ret; 129 130 ret=(DSA *)OPENSSL_malloc(sizeof(DSA)); 131 if (ret == NULL) 132 { 133 DSAerr(DSA_F_DSA_NEW_METHOD,ERR_R_MALLOC_FAILURE); 134 return(NULL); 135 } 136 ret->meth = DSA_get_default_method(); 137#ifndef OPENSSL_NO_ENGINE 138 if (engine) 139 { 140 if (!ENGINE_init(engine)) 141 { 142 DSAerr(DSA_F_DSA_NEW_METHOD, ERR_R_ENGINE_LIB); 143 OPENSSL_free(ret); 144 return NULL; 145 } 146 ret->engine = engine; 147 } 148 else 149 ret->engine = ENGINE_get_default_DSA(); 150 if(ret->engine) 151 { 152 ret->meth = ENGINE_get_DSA(ret->engine); 153 if(!ret->meth) 154 { 155 DSAerr(DSA_F_DSA_NEW_METHOD, 156 ERR_R_ENGINE_LIB); 157 ENGINE_finish(ret->engine); 158 OPENSSL_free(ret); 159 return NULL; 160 } 161 } 162#endif 163 164 ret->pad=0; 165 ret->version=0; 166 ret->write_params=1; 167 ret->p=NULL; 168 ret->q=NULL; 169 ret->g=NULL; 170 171 ret->pub_key=NULL; 172 ret->priv_key=NULL; 173 174 ret->kinv=NULL; 175 ret->r=NULL; 176 ret->method_mont_p=NULL; 177 178 ret->references=1; 179 ret->flags=ret->meth->flags & ~DSA_FLAG_NON_FIPS_ALLOW; 180 CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data); 181 if ((ret->meth->init != NULL) && !ret->meth->init(ret)) 182 { 183#ifndef OPENSSL_NO_ENGINE 184 if (ret->engine) 185 ENGINE_finish(ret->engine); 186#endif 187 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, ret, &ret->ex_data); 188 OPENSSL_free(ret); 189 ret=NULL; 190 } 191 192 return(ret); 193 } 194 195void DSA_free(DSA *r) 196 { 197 int i; 198 199 if (r == NULL) return; 200 201 i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA); 202#ifdef REF_PRINT 203 REF_PRINT("DSA",r); 204#endif 205 if (i > 0) return; 206#ifdef REF_CHECK 207 if (i < 0) 208 { 209 fprintf(stderr,"DSA_free, bad reference count\n"); 210 abort(); 211 } 212#endif 213 214 if(r->meth->finish) 215 r->meth->finish(r); 216#ifndef OPENSSL_NO_ENGINE 217 if(r->engine) 218 ENGINE_finish(r->engine); 219#endif 220 221 CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DSA, r, &r->ex_data); 222 223 if (r->p != NULL) BN_clear_free(r->p); 224 if (r->q != NULL) BN_clear_free(r->q); 225 if (r->g != NULL) BN_clear_free(r->g); 226 if (r->pub_key != NULL) BN_clear_free(r->pub_key); 227 if (r->priv_key != NULL) BN_clear_free(r->priv_key); 228 if (r->kinv != NULL) BN_clear_free(r->kinv); 229 if (r->r != NULL) BN_clear_free(r->r); 230 OPENSSL_free(r); 231 } 232 233int DSA_up_ref(DSA *r) 234 { 235 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DSA); 236#ifdef REF_PRINT 237 REF_PRINT("DSA",r); 238#endif 239#ifdef REF_CHECK 240 if (i < 2) 241 { 242 fprintf(stderr, "DSA_up_ref, bad reference count\n"); 243 abort(); 244 } 245#endif 246 return ((i > 1) ? 1 : 0); 247 } 248 249int DSA_size(const DSA *r) 250 { 251 int ret,i; 252 ASN1_INTEGER bs; 253 unsigned char buf[4]; /* 4 bytes looks really small. 254 However, i2d_ASN1_INTEGER() will not look 255 beyond the first byte, as long as the second 256 parameter is NULL. */ 257 258 i=BN_num_bits(r->q); 259 bs.length=(i+7)/8; 260 bs.data=buf; 261 bs.type=V_ASN1_INTEGER; 262 /* If the top bit is set the asn1 encoding is 1 larger. */ 263 buf[0]=0xff; 264 265 i=i2d_ASN1_INTEGER(&bs,NULL); 266 i+=i; /* r and s */ 267 ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE); 268 return(ret); 269 } 270 271int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func, 272 CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func) 273 { 274 return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DSA, argl, argp, 275 new_func, dup_func, free_func); 276 } 277 278int DSA_set_ex_data(DSA *d, int idx, void *arg) 279 { 280 return(CRYPTO_set_ex_data(&d->ex_data,idx,arg)); 281 } 282 283void *DSA_get_ex_data(DSA *d, int idx) 284 { 285 return(CRYPTO_get_ex_data(&d->ex_data,idx)); 286 } 287 288#ifndef OPENSSL_NO_DH 289DH *DSA_dup_DH(const DSA *r) 290 { 291 /* DSA has p, q, g, optional pub_key, optional priv_key. 292 * DH has p, optional length, g, optional pub_key, optional priv_key, 293 * optional q. 294 */ 295 296 DH *ret = NULL; 297 298 if (r == NULL) 299 goto err; 300 ret = DH_new(); 301 if (ret == NULL) 302 goto err; 303 if (r->p != NULL) 304 if ((ret->p = BN_dup(r->p)) == NULL) 305 goto err; 306 if (r->q != NULL) 307 { 308 ret->length = BN_num_bits(r->q); 309 if ((ret->q = BN_dup(r->q)) == NULL) 310 goto err; 311 } 312 if (r->g != NULL) 313 if ((ret->g = BN_dup(r->g)) == NULL) 314 goto err; 315 if (r->pub_key != NULL) 316 if ((ret->pub_key = BN_dup(r->pub_key)) == NULL) 317 goto err; 318 if (r->priv_key != NULL) 319 if ((ret->priv_key = BN_dup(r->priv_key)) == NULL) 320 goto err; 321 322 return ret; 323 324 err: 325 if (ret != NULL) 326 DH_free(ret); 327 return NULL; 328 } 329#endif 330