1 /* $OpenBSD: ecdsatest.c,v 1.13 2022/08/31 09:39:59 tb Exp $ */ 2 /* 3 * Written by Nils Larsch for the OpenSSL project. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 2000-2005 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 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. 60 * 61 * Portions of the attached software ("Contribution") are developed by 62 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. 63 * 64 * The Contribution is licensed pursuant to the OpenSSL open source 65 * license provided above. 66 * 67 * The elliptic curve binary polynomial software is originally written by 68 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems Laboratories. 69 * 70 */ 71 72 #include <stdio.h> 73 #include <stdlib.h> 74 #include <string.h> 75 76 #include <openssl/crypto.h> 77 #include <openssl/bio.h> 78 #include <openssl/evp.h> 79 #include <openssl/bn.h> 80 #include <openssl/ecdsa.h> 81 #ifndef OPENSSL_NO_ENGINE 82 #include <openssl/engine.h> 83 #endif 84 #include <openssl/err.h> 85 86 /* declaration of the test functions */ 87 int x9_62_test_internal(BIO *out, int nid, const char *r, const char *s); 88 int test_builtin(BIO *); 89 90 /* some tests from the X9.62 draft */ 91 int 92 x9_62_test_internal(BIO *out, int nid, const char *r_in, const char *s_in) 93 { 94 int ret = 0; 95 const char message[] = "abc"; 96 unsigned char digest[20]; 97 unsigned int dgst_len = 0; 98 EVP_MD_CTX *md_ctx = NULL; 99 EC_KEY *key = NULL; 100 ECDSA_SIG *signature = NULL; 101 BIGNUM *r = NULL, *s = NULL; 102 103 if ((md_ctx = EVP_MD_CTX_new()) == NULL) 104 goto x962_int_err; 105 /* get the message digest */ 106 if (!EVP_DigestInit(md_ctx, EVP_sha1())) 107 goto x962_int_err; 108 if (!EVP_DigestUpdate(md_ctx, (const void*)message, 3)) 109 goto x962_int_err; 110 if (!EVP_DigestFinal(md_ctx, digest, &dgst_len)) 111 goto x962_int_err; 112 113 BIO_printf(out, "testing %s: ", OBJ_nid2sn(nid)); 114 /* create the key */ 115 if ((key = EC_KEY_new_by_curve_name(nid)) == NULL) 116 goto x962_int_err; 117 if (!EC_KEY_generate_key(key)) 118 goto x962_int_err; 119 BIO_printf(out, "."); 120 (void)BIO_flush(out); 121 /* create the signature */ 122 signature = ECDSA_do_sign(digest, 20, key); 123 if (signature == NULL) 124 goto x962_int_err; 125 BIO_printf(out, "."); 126 (void)BIO_flush(out); 127 /* compare the created signature with the expected signature */ 128 if ((r = BN_new()) == NULL || (s = BN_new()) == NULL) 129 goto x962_int_err; 130 if (!BN_dec2bn(&r, r_in) || 131 !BN_dec2bn(&s, s_in)) 132 goto x962_int_err; 133 if (BN_cmp(ECDSA_SIG_get0_r(signature), r) || 134 BN_cmp(ECDSA_SIG_get0_s(signature), s)) 135 goto x962_int_err; 136 BIO_printf(out, "."); 137 (void)BIO_flush(out); 138 /* verify the signature */ 139 if (ECDSA_do_verify(digest, 20, signature, key) != 1) 140 goto x962_int_err; 141 BIO_printf(out, "."); 142 (void)BIO_flush(out); 143 144 BIO_printf(out, " ok\n"); 145 ret = 1; 146 x962_int_err: 147 if (!ret) 148 BIO_printf(out, " failed\n"); 149 if (key) 150 EC_KEY_free(key); 151 if (signature) 152 ECDSA_SIG_free(signature); 153 if (r) 154 BN_free(r); 155 if (s) 156 BN_free(s); 157 EVP_MD_CTX_free(md_ctx); 158 return ret; 159 } 160 161 int 162 test_builtin(BIO *out) 163 { 164 EC_builtin_curve *curves = NULL; 165 size_t num_curves = 0, n = 0; 166 EC_KEY *eckey = NULL, *wrong_eckey = NULL; 167 EC_GROUP *group; 168 ECDSA_SIG *ecdsa_sig = NULL; 169 BIGNUM *r = NULL, *s = NULL; 170 unsigned char digest[20], wrong_digest[20]; 171 unsigned char *signature = NULL; 172 const unsigned char *sig_ptr; 173 unsigned char *sig_ptr2; 174 unsigned char *raw_buf = NULL; 175 unsigned int sig_len, degree, r_len, s_len, bn_len, buf_len; 176 int nid, ret = 0; 177 178 /* fill digest values with some random data */ 179 arc4random_buf(digest, 20); 180 arc4random_buf(wrong_digest, 20); 181 182 /* create and verify a ecdsa signature with every available curve */ 183 BIO_printf(out, "\ntesting ECDSA_sign() and ECDSA_verify() " 184 "with some internal curves:\n"); 185 186 /* get a list of all internal curves */ 187 num_curves = EC_get_builtin_curves(NULL, 0); 188 189 curves = reallocarray(NULL, sizeof(EC_builtin_curve), num_curves); 190 191 if (curves == NULL) { 192 BIO_printf(out, "reallocarray error\n"); 193 goto builtin_err; 194 } 195 196 if (!EC_get_builtin_curves(curves, num_curves)) { 197 BIO_printf(out, "unable to get internal curves\n"); 198 goto builtin_err; 199 } 200 201 /* now create and verify a signature for every curve */ 202 for (n = 0; n < num_curves; n++) { 203 unsigned char dirt, offset; 204 205 nid = curves[n].nid; 206 if (nid == NID_ipsec4) 207 continue; 208 /* create new ecdsa key (== EC_KEY) */ 209 if ((eckey = EC_KEY_new()) == NULL) 210 goto builtin_err; 211 group = EC_GROUP_new_by_curve_name(nid); 212 if (group == NULL) 213 goto builtin_err; 214 if (EC_KEY_set_group(eckey, group) == 0) 215 goto builtin_err; 216 EC_GROUP_free(group); 217 degree = EC_GROUP_get_degree(EC_KEY_get0_group(eckey)); 218 if (degree < 160) { 219 /* drop the curve */ 220 EC_KEY_free(eckey); 221 eckey = NULL; 222 continue; 223 } 224 BIO_printf(out, "%s: ", OBJ_nid2sn(nid)); 225 /* create key */ 226 if (!EC_KEY_generate_key(eckey)) { 227 BIO_printf(out, " failed\n"); 228 goto builtin_err; 229 } 230 /* create second key */ 231 if ((wrong_eckey = EC_KEY_new()) == NULL) 232 goto builtin_err; 233 group = EC_GROUP_new_by_curve_name(nid); 234 if (group == NULL) 235 goto builtin_err; 236 if (EC_KEY_set_group(wrong_eckey, group) == 0) 237 goto builtin_err; 238 EC_GROUP_free(group); 239 if (!EC_KEY_generate_key(wrong_eckey)) { 240 BIO_printf(out, " failed\n"); 241 goto builtin_err; 242 } 243 244 BIO_printf(out, "."); 245 (void)BIO_flush(out); 246 /* check key */ 247 if (!EC_KEY_check_key(eckey)) { 248 BIO_printf(out, " failed\n"); 249 goto builtin_err; 250 } 251 BIO_printf(out, "."); 252 (void)BIO_flush(out); 253 /* create signature */ 254 if ((sig_len = ECDSA_size(eckey)) == 0) 255 goto builtin_err; 256 if ((signature = malloc(sig_len)) == NULL) 257 goto builtin_err; 258 if (!ECDSA_sign(0, digest, 20, signature, &sig_len, eckey)) { 259 BIO_printf(out, " failed\n"); 260 goto builtin_err; 261 } 262 BIO_printf(out, "."); 263 (void)BIO_flush(out); 264 /* verify signature */ 265 if (ECDSA_verify(0, digest, 20, signature, sig_len, 266 eckey) != 1) { 267 BIO_printf(out, " failed\n"); 268 goto builtin_err; 269 } 270 BIO_printf(out, "."); 271 (void)BIO_flush(out); 272 /* verify signature with the wrong key */ 273 if (ECDSA_verify(0, digest, 20, signature, sig_len, 274 wrong_eckey) == 1) { 275 BIO_printf(out, " failed\n"); 276 goto builtin_err; 277 } 278 BIO_printf(out, "."); 279 (void)BIO_flush(out); 280 /* wrong digest */ 281 if (ECDSA_verify(0, wrong_digest, 20, signature, sig_len, 282 eckey) == 1) { 283 BIO_printf(out, " failed\n"); 284 goto builtin_err; 285 } 286 BIO_printf(out, "."); 287 (void)BIO_flush(out); 288 /* wrong length */ 289 if (ECDSA_verify(0, digest, 20, signature, sig_len - 1, 290 eckey) == 1) { 291 BIO_printf(out, " failed\n"); 292 goto builtin_err; 293 } 294 BIO_printf(out, "."); 295 (void)BIO_flush(out); 296 297 /* 298 * Modify a single byte of the signature: to ensure we don't 299 * garble the ASN1 structure, we read the raw signature and 300 * modify a byte in one of the bignums directly. 301 */ 302 sig_ptr = signature; 303 if ((ecdsa_sig = d2i_ECDSA_SIG(NULL, &sig_ptr, 304 sig_len)) == NULL) { 305 BIO_printf(out, " failed\n"); 306 goto builtin_err; 307 } 308 309 /* Store the two BIGNUMs in raw_buf. */ 310 r_len = BN_num_bytes(ECDSA_SIG_get0_r(ecdsa_sig)); 311 s_len = BN_num_bytes(ECDSA_SIG_get0_s(ecdsa_sig)); 312 bn_len = (degree + 7) / 8; 313 if ((r_len > bn_len) || (s_len > bn_len)) { 314 BIO_printf(out, " failed\n"); 315 goto builtin_err; 316 } 317 buf_len = 2 * bn_len; 318 if ((raw_buf = calloc(1, buf_len)) == NULL) 319 goto builtin_err; 320 BN_bn2bin(ECDSA_SIG_get0_r(ecdsa_sig), raw_buf + bn_len - r_len); 321 BN_bn2bin(ECDSA_SIG_get0_s(ecdsa_sig), raw_buf + buf_len - s_len); 322 323 /* Modify a single byte in the buffer. */ 324 offset = raw_buf[10] % buf_len; 325 dirt = raw_buf[11] ? raw_buf[11] : 1; 326 raw_buf[offset] ^= dirt; 327 /* Now read the BIGNUMs back in from raw_buf. */ 328 if ((r = BN_bin2bn(raw_buf, bn_len, NULL)) == NULL || 329 (s = BN_bin2bn(raw_buf + bn_len, bn_len, NULL)) == NULL) 330 goto builtin_err; 331 if (!ECDSA_SIG_set0(ecdsa_sig, r, s)) 332 goto builtin_err; 333 r = NULL; 334 s = NULL; 335 336 if ((sig_len = i2d_ECDSA_SIG(ecdsa_sig, NULL)) <= 0) 337 goto builtin_err; 338 free(signature); 339 if ((signature = calloc(1, sig_len)) == NULL) 340 goto builtin_err; 341 342 sig_ptr2 = signature; 343 if ((sig_len = i2d_ECDSA_SIG(ecdsa_sig, &sig_ptr2)) <= 0) 344 goto builtin_err; 345 if (ECDSA_verify(0, digest, 20, signature, sig_len, 346 eckey) == 1) { 347 BIO_printf(out, " failed\n"); 348 goto builtin_err; 349 } 350 /* Sanity check: undo the modification and verify signature. */ 351 raw_buf[offset] ^= dirt; 352 if ((r = BN_bin2bn(raw_buf, bn_len, NULL)) == NULL || 353 (s = BN_bin2bn(raw_buf + bn_len, bn_len, NULL)) == NULL) 354 goto builtin_err; 355 if (!ECDSA_SIG_set0(ecdsa_sig, r, s)) 356 goto builtin_err; 357 r = NULL; 358 s = NULL; 359 360 if ((sig_len = i2d_ECDSA_SIG(ecdsa_sig, NULL)) <= 0) 361 goto builtin_err; 362 free(signature); 363 if ((signature = calloc(1, sig_len)) == NULL) 364 goto builtin_err; 365 366 sig_ptr2 = signature; 367 if ((sig_len = i2d_ECDSA_SIG(ecdsa_sig, &sig_ptr2)) <= 0) 368 goto builtin_err; 369 if (ECDSA_verify(0, digest, 20, signature, sig_len, 370 eckey) != 1) { 371 BIO_printf(out, " failed\n"); 372 goto builtin_err; 373 } 374 BIO_printf(out, "."); 375 (void)BIO_flush(out); 376 377 BIO_printf(out, " ok\n"); 378 /* cleanup */ 379 /* clean bogus errors */ 380 ERR_clear_error(); 381 free(signature); 382 signature = NULL; 383 EC_KEY_free(eckey); 384 eckey = NULL; 385 EC_KEY_free(wrong_eckey); 386 wrong_eckey = NULL; 387 ECDSA_SIG_free(ecdsa_sig); 388 ecdsa_sig = NULL; 389 free(raw_buf); 390 raw_buf = NULL; 391 } 392 393 ret = 1; 394 builtin_err: 395 BN_free(r); 396 BN_free(s); 397 EC_KEY_free(eckey); 398 EC_KEY_free(wrong_eckey); 399 ECDSA_SIG_free(ecdsa_sig); 400 free(signature); 401 free(raw_buf); 402 free(curves); 403 404 return ret; 405 } 406 407 int 408 main(void) 409 { 410 int ret = 1; 411 BIO *out; 412 413 out = BIO_new_fp(stdout, BIO_NOCLOSE); 414 415 ERR_load_crypto_strings(); 416 417 /* the tests */ 418 if (!test_builtin(out)) 419 goto err; 420 421 ret = 0; 422 err: 423 if (ret) 424 BIO_printf(out, "\nECDSA test failed\n"); 425 else 426 BIO_printf(out, "\nECDSA test passed\n"); 427 if (ret) 428 ERR_print_errors(out); 429 CRYPTO_cleanup_all_ex_data(); 430 ERR_remove_thread_state(NULL); 431 ERR_free_strings(); 432 CRYPTO_mem_leaks(out); 433 if (out != NULL) 434 BIO_free(out); 435 return ret; 436 } 437