1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) 2 * All rights reserved. 3 * 4 * This package is an SSL implementation written 5 * by Eric Young (eay@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@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@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@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@sheba.arc.nasa.gov>. */ 59 60 #ifndef OPENSSL_HEADER_DSA_H 61 #define OPENSSL_HEADER_DSA_H 62 63 #include <openssl/base.h> 64 65 #include <openssl/engine.h> 66 #include <openssl/ex_data.h> 67 #include <openssl/thread.h> 68 69 #if defined(__cplusplus) 70 extern "C" { 71 #endif 72 73 74 /* DSA contains functions for signing and verifying with the Digital Signature 75 * Algorithm. */ 76 77 78 /* Allocation and destruction. */ 79 80 /* DSA_new returns a new, empty DSA object or NULL on error. */ 81 OPENSSL_EXPORT DSA *DSA_new(void); 82 83 /* DSA_free decrements the reference count of |dsa| and frees it if the 84 * reference count drops to zero. */ 85 OPENSSL_EXPORT void DSA_free(DSA *dsa); 86 87 /* DSA_up_ref increments the reference count of |dsa| and returns one. */ 88 OPENSSL_EXPORT int DSA_up_ref(DSA *dsa); 89 90 91 /* Properties. */ 92 93 /* DSA_get0_key sets |*out_pub_key| and |*out_priv_key|, if non-NULL, to |dsa|'s 94 * public and private key, respectively. If |dsa| is a public key, the private 95 * key will be set to NULL. */ 96 OPENSSL_EXPORT void DSA_get0_key(const DSA *dsa, const BIGNUM **out_pub_key, 97 const BIGNUM **out_priv_key); 98 99 /* DSA_get0_pqg sets |*out_p|, |*out_q|, and |*out_g|, if non-NULL, to |dsa|'s 100 * p, q, and g parameters, respectively. */ 101 OPENSSL_EXPORT void DSA_get0_pqg(const DSA *dsa, const BIGNUM **out_p, 102 const BIGNUM **out_q, const BIGNUM **out_g); 103 104 105 /* Parameter generation. */ 106 107 /* DSA_generate_parameters_ex generates a set of DSA parameters by following 108 * the procedure given in FIPS 186-4, appendix A. 109 * (http://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.186-4.pdf) 110 * 111 * The larger prime will have a length of |bits| (e.g. 2048). The |seed| value 112 * allows others to generate and verify the same parameters and should be 113 * random input which is kept for reference. If |out_counter| or |out_h| are 114 * not NULL then the counter and h value used in the generation are written to 115 * them. 116 * 117 * The |cb| argument is passed to |BN_generate_prime_ex| and is thus called 118 * during the generation process in order to indicate progress. See the 119 * comments for that function for details. In addition to the calls made by 120 * |BN_generate_prime_ex|, |DSA_generate_parameters_ex| will call it with 121 * |event| equal to 2 and 3 at different stages of the process. 122 * 123 * It returns one on success and zero otherwise. */ 124 OPENSSL_EXPORT int DSA_generate_parameters_ex(DSA *dsa, unsigned bits, 125 const uint8_t *seed, 126 size_t seed_len, int *out_counter, 127 unsigned long *out_h, 128 BN_GENCB *cb); 129 130 /* DSAparams_dup returns a freshly allocated |DSA| that contains a copy of the 131 * parameters from |dsa|. It returns NULL on error. */ 132 OPENSSL_EXPORT DSA *DSAparams_dup(const DSA *dsa); 133 134 135 /* Key generation. */ 136 137 /* DSA_generate_key generates a public/private key pair in |dsa|, which must 138 * already have parameters setup. It returns one on success and zero on 139 * error. */ 140 OPENSSL_EXPORT int DSA_generate_key(DSA *dsa); 141 142 143 /* Signatures. */ 144 145 /* DSA_SIG_st (aka |DSA_SIG|) contains a DSA signature as a pair of integers. */ 146 struct DSA_SIG_st { 147 BIGNUM *r, *s; 148 }; 149 150 /* DSA_SIG_new returns a freshly allocated, DIG_SIG structure or NULL on error. 151 * Both |r| and |s| in the signature will be NULL. */ 152 OPENSSL_EXPORT DSA_SIG *DSA_SIG_new(void); 153 154 /* DSA_SIG_free frees the contents of |sig| and then frees |sig| itself. */ 155 OPENSSL_EXPORT void DSA_SIG_free(DSA_SIG *sig); 156 157 /* DSA_do_sign returns a signature of the hash in |digest| by the key in |dsa| 158 * and returns an allocated, DSA_SIG structure, or NULL on error. */ 159 OPENSSL_EXPORT DSA_SIG *DSA_do_sign(const uint8_t *digest, size_t digest_len, 160 DSA *dsa); 161 162 /* DSA_do_verify verifies that |sig| is a valid signature, by the public key in 163 * |dsa|, of the hash in |digest|. It returns one if so, zero if invalid and -1 164 * on error. 165 * 166 * WARNING: do not use. This function returns -1 for error, 0 for invalid and 1 167 * for valid. However, this is dangerously different to the usual OpenSSL 168 * convention and could be a disaster if a user did |if (DSA_do_verify(...))|. 169 * Because of this, |DSA_check_signature| is a safer version of this. 170 * 171 * TODO(fork): deprecate. */ 172 OPENSSL_EXPORT int DSA_do_verify(const uint8_t *digest, size_t digest_len, 173 DSA_SIG *sig, const DSA *dsa); 174 175 /* DSA_do_check_signature sets |*out_valid| to zero. Then it verifies that |sig| 176 * is a valid signature, by the public key in |dsa| of the hash in |digest| 177 * and, if so, it sets |*out_valid| to one. 178 * 179 * It returns one if it was able to verify the signature as valid or invalid, 180 * and zero on error. */ 181 OPENSSL_EXPORT int DSA_do_check_signature(int *out_valid, const uint8_t *digest, 182 size_t digest_len, DSA_SIG *sig, 183 const DSA *dsa); 184 185 186 /* ASN.1 signatures. 187 * 188 * These functions also perform DSA signature operations, but deal with ASN.1 189 * encoded signatures as opposed to raw |BIGNUM|s. If you don't know what 190 * encoding a DSA signature is in, it's probably ASN.1. */ 191 192 /* DSA_sign signs |digest| with the key in |dsa| and writes the resulting 193 * signature, in ASN.1 form, to |out_sig| and the length of the signature to 194 * |*out_siglen|. There must be, at least, |DSA_size(dsa)| bytes of space in 195 * |out_sig|. It returns one on success and zero otherwise. 196 * 197 * (The |type| argument is ignored.) */ 198 OPENSSL_EXPORT int DSA_sign(int type, const uint8_t *digest, size_t digest_len, 199 uint8_t *out_sig, unsigned int *out_siglen, 200 DSA *dsa); 201 202 /* DSA_verify verifies that |sig| is a valid, ASN.1 signature, by the public 203 * key in |dsa|, of the hash in |digest|. It returns one if so, zero if invalid 204 * and -1 on error. 205 * 206 * (The |type| argument is ignored.) 207 * 208 * WARNING: do not use. This function returns -1 for error, 0 for invalid and 1 209 * for valid. However, this is dangerously different to the usual OpenSSL 210 * convention and could be a disaster if a user did |if (DSA_do_verify(...))|. 211 * Because of this, |DSA_check_signature| is a safer version of this. 212 * 213 * TODO(fork): deprecate. */ 214 OPENSSL_EXPORT int DSA_verify(int type, const uint8_t *digest, 215 size_t digest_len, const uint8_t *sig, 216 size_t sig_len, const DSA *dsa); 217 218 /* DSA_check_signature sets |*out_valid| to zero. Then it verifies that |sig| 219 * is a valid, ASN.1 signature, by the public key in |dsa|, of the hash in 220 * |digest|. If so, it sets |*out_valid| to one. 221 * 222 * It returns one if it was able to verify the signature as valid or invalid, 223 * and zero on error. */ 224 OPENSSL_EXPORT int DSA_check_signature(int *out_valid, const uint8_t *digest, 225 size_t digest_len, const uint8_t *sig, 226 size_t sig_len, const DSA *dsa); 227 228 /* DSA_size returns the size, in bytes, of an ASN.1 encoded, DSA signature 229 * generated by |dsa|. Parameters must already have been setup in |dsa|. */ 230 OPENSSL_EXPORT int DSA_size(const DSA *dsa); 231 232 233 /* ASN.1 encoding. */ 234 235 /* DSA_SIG_parse parses a DER-encoded DSA-Sig-Value structure from |cbs| and 236 * advances |cbs|. It returns a newly-allocated |DSA_SIG| or NULL on error. */ 237 OPENSSL_EXPORT DSA_SIG *DSA_SIG_parse(CBS *cbs); 238 239 /* DSA_SIG_marshal marshals |sig| as a DER-encoded DSA-Sig-Value and appends the 240 * result to |cbb|. It returns one on success and zero on error. */ 241 OPENSSL_EXPORT int DSA_SIG_marshal(CBB *cbb, const DSA_SIG *sig); 242 243 /* DSA_parse_public_key parses a DER-encoded DSA public key from |cbs| and 244 * advances |cbs|. It returns a newly-allocated |DSA| or NULL on error. */ 245 OPENSSL_EXPORT DSA *DSA_parse_public_key(CBS *cbs); 246 247 /* DSA_marshal_public_key marshals |dsa| as a DER-encoded DSA public key and 248 * appends the result to |cbb|. It returns one on success and zero on 249 * failure. */ 250 OPENSSL_EXPORT int DSA_marshal_public_key(CBB *cbb, const DSA *dsa); 251 252 /* DSA_parse_private_key parses a DER-encoded DSA private key from |cbs| and 253 * advances |cbs|. It returns a newly-allocated |DSA| or NULL on error. */ 254 OPENSSL_EXPORT DSA *DSA_parse_private_key(CBS *cbs); 255 256 /* DSA_marshal_private_key marshals |dsa| as a DER-encoded DSA private key and 257 * appends the result to |cbb|. It returns one on success and zero on 258 * failure. */ 259 OPENSSL_EXPORT int DSA_marshal_private_key(CBB *cbb, const DSA *dsa); 260 261 /* DSA_parse_parameters parses a DER-encoded Dss-Parms structure (RFC 3279) 262 * from |cbs| and advances |cbs|. It returns a newly-allocated |DSA| or NULL on 263 * error. */ 264 OPENSSL_EXPORT DSA *DSA_parse_parameters(CBS *cbs); 265 266 /* DSA_marshal_parameters marshals |dsa| as a DER-encoded Dss-Parms structure 267 * (RFC 3447) and appends the result to |cbb|. It returns one on success and 268 * zero on failure. */ 269 OPENSSL_EXPORT int DSA_marshal_parameters(CBB *cbb, const DSA *dsa); 270 271 272 /* Precomputation. */ 273 274 /* DSA_sign_setup precomputes the message independent part of the DSA signature 275 * and writes them to |*out_kinv| and |*out_r|. Returns one on success, zero on 276 * error. 277 * 278 * TODO(fork): decide what to do with this. Since making DSA* opaque there's no 279 * way for the user to install them. Also, it forces the DSA* not to be const 280 * when passing to the signing function. */ 281 OPENSSL_EXPORT int DSA_sign_setup(const DSA *dsa, BN_CTX *ctx, 282 BIGNUM **out_kinv, BIGNUM **out_r); 283 284 285 /* Conversion. */ 286 287 /* DSA_dup_DH returns a |DH| constructed from the parameters of |dsa|. This is 288 * sometimes needed when Diffie-Hellman parameters are stored in the form of 289 * DSA parameters. It returns an allocated |DH| on success or NULL on error. */ 290 OPENSSL_EXPORT DH *DSA_dup_DH(const DSA *dsa); 291 292 293 /* ex_data functions. 294 * 295 * See |ex_data.h| for details. */ 296 297 OPENSSL_EXPORT int DSA_get_ex_new_index(long argl, void *argp, 298 CRYPTO_EX_unused *unused, 299 CRYPTO_EX_dup *dup_unused, 300 CRYPTO_EX_free *free_func); 301 OPENSSL_EXPORT int DSA_set_ex_data(DSA *d, int idx, void *arg); 302 OPENSSL_EXPORT void *DSA_get_ex_data(const DSA *d, int idx); 303 304 305 /* Deprecated functions. */ 306 307 /* d2i_DSA_SIG parses an ASN.1, DER-encoded, DSA signature from |len| bytes at 308 * |*inp|. If |out_sig| is not NULL then, on exit, a pointer to the result is 309 * in |*out_sig|. Note that, even if |*out_sig| is already non-NULL on entry, it 310 * will not be written to. Rather, a fresh |DSA_SIG| is allocated and the 311 * previous one is freed. On successful exit, |*inp| is advanced past the DER 312 * structure. It returns the result or NULL on error. 313 * 314 * Use |DSA_SIG_parse| instead. */ 315 OPENSSL_EXPORT DSA_SIG *d2i_DSA_SIG(DSA_SIG **out_sig, const uint8_t **inp, 316 long len); 317 318 /* i2d_DSA_SIG marshals |in| to an ASN.1, DER structure. If |outp| is not NULL 319 * then the result is written to |*outp| and |*outp| is advanced just past the 320 * output. It returns the number of bytes in the result, whether written or not, 321 * or a negative value on error. 322 * 323 * Use |DSA_SIG_marshal| instead. */ 324 OPENSSL_EXPORT int i2d_DSA_SIG(const DSA_SIG *in, uint8_t **outp); 325 326 /* d2i_DSAPublicKey parses an ASN.1, DER-encoded, DSA public key from |len| 327 * bytes at |*inp|. If |out| is not NULL then, on exit, a pointer to the result 328 * is in |*out|. Note that, even if |*ou| is already non-NULL on entry, it will 329 * not be written to. Rather, a fresh |DSA| is allocated and the previous one is 330 * freed. On successful exit, |*inp| is advanced past the DER structure. It 331 * returns the result or NULL on error. 332 * 333 * Use |DSA_parse_public_key| instead. */ 334 OPENSSL_EXPORT DSA *d2i_DSAPublicKey(DSA **out, const uint8_t **inp, long len); 335 336 /* i2d_DSAPublicKey marshals a public key from |in| to an ASN.1, DER structure. 337 * If |outp| is not NULL then the result is written to |*outp| and |*outp| is 338 * advanced just past the output. It returns the number of bytes in the result, 339 * whether written or not, or a negative value on error. 340 * 341 * Use |DSA_marshal_public_key| instead. */ 342 OPENSSL_EXPORT int i2d_DSAPublicKey(const DSA *in, uint8_t **outp); 343 344 /* d2i_DSAPrivateKey parses an ASN.1, DER-encoded, DSA private key from |len| 345 * bytes at |*inp|. If |out| is not NULL then, on exit, a pointer to the result 346 * is in |*out|. Note that, even if |*out| is already non-NULL on entry, it will 347 * not be written to. Rather, a fresh |DSA| is allocated and the previous one is 348 * freed. On successful exit, |*inp| is advanced past the DER structure. It 349 * returns the result or NULL on error. 350 * 351 * Use |DSA_parse_private_key| instead. */ 352 OPENSSL_EXPORT DSA *d2i_DSAPrivateKey(DSA **out, const uint8_t **inp, long len); 353 354 /* i2d_DSAPrivateKey marshals a private key from |in| to an ASN.1, DER 355 * structure. If |outp| is not NULL then the result is written to |*outp| and 356 * |*outp| is advanced just past the output. It returns the number of bytes in 357 * the result, whether written or not, or a negative value on error. 358 * 359 * Use |DSA_marshal_private_key| instead. */ 360 OPENSSL_EXPORT int i2d_DSAPrivateKey(const DSA *in, uint8_t **outp); 361 362 /* d2i_DSAparams parses ASN.1, DER-encoded, DSA parameters from |len| bytes at 363 * |*inp|. If |out| is not NULL then, on exit, a pointer to the result is in 364 * |*out|. Note that, even if |*out| is already non-NULL on entry, it will not 365 * be written to. Rather, a fresh |DSA| is allocated and the previous one is 366 * freed. On successful exit, |*inp| is advanced past the DER structure. It 367 * returns the result or NULL on error. 368 * 369 * Use |DSA_parse_parameters| instead. */ 370 OPENSSL_EXPORT DSA *d2i_DSAparams(DSA **out, const uint8_t **inp, long len); 371 372 /* i2d_DSAparams marshals DSA parameters from |in| to an ASN.1, DER structure. 373 * If |outp| is not NULL then the result is written to |*outp| and |*outp| is 374 * advanced just past the output. It returns the number of bytes in the result, 375 * whether written or not, or a negative value on error. 376 * 377 * Use |DSA_marshal_parameters| instead. */ 378 OPENSSL_EXPORT int i2d_DSAparams(const DSA *in, uint8_t **outp); 379 380 /* DSA_generate_parameters is a deprecated version of 381 * |DSA_generate_parameters_ex| that creates and returns a |DSA*|. Don't use 382 * it. */ 383 OPENSSL_EXPORT DSA *DSA_generate_parameters(int bits, unsigned char *seed, 384 int seed_len, int *counter_ret, 385 unsigned long *h_ret, 386 void (*callback)(int, int, void *), 387 void *cb_arg); 388 389 390 struct dsa_st { 391 long version; 392 BIGNUM *p; 393 BIGNUM *q; /* == 20 */ 394 BIGNUM *g; 395 396 BIGNUM *pub_key; /* y public key */ 397 BIGNUM *priv_key; /* x private key */ 398 399 BIGNUM *kinv; /* Signing pre-calc */ 400 BIGNUM *r; /* Signing pre-calc */ 401 402 int flags; 403 /* Normally used to cache montgomery values */ 404 CRYPTO_MUTEX method_mont_lock; 405 BN_MONT_CTX *method_mont_p; 406 BN_MONT_CTX *method_mont_q; 407 CRYPTO_refcount_t references; 408 CRYPTO_EX_DATA ex_data; 409 }; 410 411 412 #if defined(__cplusplus) 413 } /* extern C */ 414 415 extern "C++" { 416 417 namespace bssl { 418 419 BORINGSSL_MAKE_DELETER(DSA, DSA_free) 420 BORINGSSL_MAKE_DELETER(DSA_SIG, DSA_SIG_free) 421 422 } // namespace bssl 423 424 } /* extern C++ */ 425 426 #endif 427 428 #define DSA_R_BAD_Q_VALUE 100 429 #define DSA_R_MISSING_PARAMETERS 101 430 #define DSA_R_MODULUS_TOO_LARGE 102 431 #define DSA_R_NEED_NEW_SETUP_VALUES 103 432 #define DSA_R_BAD_VERSION 104 433 #define DSA_R_DECODE_ERROR 105 434 #define DSA_R_ENCODE_ERROR 106 435 436 #endif /* OPENSSL_HEADER_DSA_H */ 437