1 /* 2 * Copyright 2002-2023 The OpenSSL Project Authors. All Rights Reserved. 3 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved 4 * 5 * Licensed under the Apache License 2.0 (the "License"). You may not use 6 * this file except in compliance with the License. You can obtain a copy 7 * in the file LICENSE in the source distribution or at 8 * https://www.openssl.org/source/license.html 9 */ 10 11 /* 12 * Low level APIs are deprecated for public use, but still ok for internal use. 13 */ 14 #include "internal/deprecated.h" 15 16 #include <openssl/opensslconf.h> /* To see if OPENSSL_NO_EC is defined */ 17 #include "testutil.h" 18 19 #ifndef OPENSSL_NO_EC 20 21 # include <openssl/evp.h> 22 # include <openssl/bn.h> 23 # include <openssl/ec.h> 24 # include <openssl/rand.h> 25 # include "internal/nelem.h" 26 # include "ecdsatest.h" 27 28 static fake_random_generate_cb fbytes; 29 30 static const char *numbers[2]; 31 static size_t crv_len = 0; 32 static EC_builtin_curve *curves = NULL; 33 static OSSL_PROVIDER *fake_rand = NULL; 34 35 static int fbytes(unsigned char *buf, size_t num, ossl_unused const char *name, 36 EVP_RAND_CTX *ctx) 37 { 38 int ret = 0; 39 static int fbytes_counter = 0; 40 BIGNUM *tmp = NULL; 41 42 fake_rand_set_callback(ctx, NULL); 43 44 if (!TEST_ptr(tmp = BN_new()) 45 || !TEST_int_lt(fbytes_counter, OSSL_NELEM(numbers)) 46 || !TEST_true(BN_hex2bn(&tmp, numbers[fbytes_counter])) 47 /* tmp might need leading zeros so pad it out */ 48 || !TEST_int_le(BN_num_bytes(tmp), num) 49 || !TEST_int_gt(BN_bn2binpad(tmp, buf, num), 0)) 50 goto err; 51 52 fbytes_counter = (fbytes_counter + 1) % OSSL_NELEM(numbers); 53 ret = 1; 54 err: 55 BN_free(tmp); 56 return ret; 57 } 58 59 /*- 60 * This function hijacks the RNG to feed it the chosen ECDSA key and nonce. 61 * The ECDSA KATs are from: 62 * - the X9.62 draft (4) 63 * - NIST CAVP (720) 64 * 65 * It uses the low-level ECDSA_sign_setup instead of EVP to control the RNG. 66 * NB: This is not how applications should use ECDSA; this is only for testing. 67 * 68 * Tests the library can successfully: 69 * - generate public keys that matches those KATs 70 * - create ECDSA signatures that match those KATs 71 * - accept those signatures as valid 72 */ 73 static int x9_62_tests(int n) 74 { 75 int nid, md_nid, ret = 0; 76 const char *r_in = NULL, *s_in = NULL, *tbs = NULL; 77 unsigned char *pbuf = NULL, *qbuf = NULL, *message = NULL; 78 unsigned char digest[EVP_MAX_MD_SIZE]; 79 unsigned int dgst_len = 0; 80 long q_len, msg_len = 0; 81 size_t p_len; 82 EVP_MD_CTX *mctx = NULL; 83 EC_KEY *key = NULL; 84 ECDSA_SIG *signature = NULL; 85 BIGNUM *r = NULL, *s = NULL; 86 BIGNUM *kinv = NULL, *rp = NULL; 87 const BIGNUM *sig_r = NULL, *sig_s = NULL; 88 89 nid = ecdsa_cavs_kats[n].nid; 90 md_nid = ecdsa_cavs_kats[n].md_nid; 91 r_in = ecdsa_cavs_kats[n].r; 92 s_in = ecdsa_cavs_kats[n].s; 93 tbs = ecdsa_cavs_kats[n].msg; 94 numbers[0] = ecdsa_cavs_kats[n].d; 95 numbers[1] = ecdsa_cavs_kats[n].k; 96 97 TEST_info("ECDSA KATs for curve %s", OBJ_nid2sn(nid)); 98 99 #ifdef FIPS_MODULE 100 if (EC_curve_nid2nist(nid) == NULL) 101 return TEST_skip("skip non approved curves"); 102 #endif /* FIPS_MODULE */ 103 104 if (!TEST_ptr(mctx = EVP_MD_CTX_new()) 105 /* get the message digest */ 106 || !TEST_ptr(message = OPENSSL_hexstr2buf(tbs, &msg_len)) 107 || !TEST_true(EVP_DigestInit_ex(mctx, EVP_get_digestbynid(md_nid), NULL)) 108 || !TEST_true(EVP_DigestUpdate(mctx, message, msg_len)) 109 || !TEST_true(EVP_DigestFinal_ex(mctx, digest, &dgst_len)) 110 /* create the key */ 111 || !TEST_ptr(key = EC_KEY_new_by_curve_name(nid)) 112 /* load KAT variables */ 113 || !TEST_ptr(r = BN_new()) 114 || !TEST_ptr(s = BN_new()) 115 || !TEST_true(BN_hex2bn(&r, r_in)) 116 || !TEST_true(BN_hex2bn(&s, s_in))) 117 goto err; 118 119 /* public key must match KAT */ 120 fake_rand_set_callback(RAND_get0_private(NULL), &fbytes); 121 if (!TEST_true(EC_KEY_generate_key(key)) 122 || !TEST_true(p_len = EC_KEY_key2buf(key, POINT_CONVERSION_UNCOMPRESSED, 123 &pbuf, NULL)) 124 || !TEST_ptr(qbuf = OPENSSL_hexstr2buf(ecdsa_cavs_kats[n].Q, &q_len)) 125 || !TEST_int_eq(q_len, p_len) 126 || !TEST_mem_eq(qbuf, q_len, pbuf, p_len)) 127 goto err; 128 129 /* create the signature via ECDSA_sign_setup to avoid use of ECDSA nonces */ 130 fake_rand_set_callback(RAND_get0_private(NULL), &fbytes); 131 if (!TEST_true(ECDSA_sign_setup(key, NULL, &kinv, &rp)) 132 || !TEST_ptr(signature = ECDSA_do_sign_ex(digest, dgst_len, 133 kinv, rp, key)) 134 /* verify the signature */ 135 || !TEST_int_eq(ECDSA_do_verify(digest, dgst_len, signature, key), 1)) 136 goto err; 137 138 /* compare the created signature with the expected signature */ 139 ECDSA_SIG_get0(signature, &sig_r, &sig_s); 140 if (!TEST_BN_eq(sig_r, r) 141 || !TEST_BN_eq(sig_s, s)) 142 goto err; 143 144 ret = 1; 145 146 err: 147 OPENSSL_free(message); 148 OPENSSL_free(pbuf); 149 OPENSSL_free(qbuf); 150 EC_KEY_free(key); 151 ECDSA_SIG_free(signature); 152 BN_free(r); 153 BN_free(s); 154 EVP_MD_CTX_free(mctx); 155 BN_clear_free(kinv); 156 BN_clear_free(rp); 157 return ret; 158 } 159 160 /*- 161 * Positive and negative ECDSA testing through EVP interface: 162 * - EVP_DigestSign (this is the one-shot version) 163 * - EVP_DigestVerify 164 * 165 * Tests the library can successfully: 166 * - create a key 167 * - create a signature 168 * - accept that signature 169 * - reject that signature with a different public key 170 * - reject that signature if its length is not correct 171 * - reject that signature after modifying the message 172 * - accept that signature after un-modifying the message 173 * - reject that signature after modifying the signature 174 * - accept that signature after un-modifying the signature 175 */ 176 static int set_sm2_id(EVP_MD_CTX *mctx, EVP_PKEY *pkey) 177 { 178 /* With the SM2 key type, the SM2 ID is mandatory */ 179 static const char sm2_id[] = { 1, 2, 3, 4, 'l', 'e', 't', 't', 'e', 'r' }; 180 EVP_PKEY_CTX *pctx; 181 182 if (!TEST_ptr(pctx = EVP_MD_CTX_get_pkey_ctx(mctx)) 183 || !TEST_int_gt(EVP_PKEY_CTX_set1_id(pctx, sm2_id, sizeof(sm2_id)), 0)) 184 return 0; 185 return 1; 186 } 187 188 static int test_builtin(int n, int as) 189 { 190 EC_KEY *eckey_neg = NULL, *eckey = NULL; 191 unsigned char dirt, offset, tbs[128]; 192 unsigned char *sig = NULL; 193 EVP_PKEY *pkey_neg = NULL, *pkey = NULL, *dup_pk = NULL; 194 EVP_MD_CTX *mctx = NULL; 195 size_t sig_len; 196 int nid, ret = 0; 197 int temp; 198 199 nid = curves[n].nid; 200 201 /* skip built-in curves where ord(G) is not prime */ 202 if (nid == NID_ipsec4 || nid == NID_ipsec3) { 203 TEST_info("skipped: ECDSA unsupported for curve %s", OBJ_nid2sn(nid)); 204 return 1; 205 } 206 207 /* 208 * skip SM2 curve if 'as' is equal to EVP_PKEY_EC or, skip all curves 209 * except SM2 curve if 'as' is equal to EVP_PKEY_SM2 210 */ 211 if (nid == NID_sm2 && as == EVP_PKEY_EC) { 212 TEST_info("skipped: EC key type unsupported for curve %s", 213 OBJ_nid2sn(nid)); 214 return 1; 215 } else if (nid != NID_sm2 && as == EVP_PKEY_SM2) { 216 TEST_info("skipped: SM2 key type unsupported for curve %s", 217 OBJ_nid2sn(nid)); 218 return 1; 219 } 220 221 TEST_info("testing ECDSA for curve %s as %s key type", OBJ_nid2sn(nid), 222 as == EVP_PKEY_EC ? "EC" : "SM2"); 223 224 if (!TEST_ptr(mctx = EVP_MD_CTX_new()) 225 /* get some random message data */ 226 || !TEST_int_gt(RAND_bytes(tbs, sizeof(tbs)), 0) 227 /* real key */ 228 || !TEST_ptr(eckey = EC_KEY_new_by_curve_name(nid)) 229 || !TEST_true(EC_KEY_generate_key(eckey)) 230 || !TEST_ptr(pkey = EVP_PKEY_new()) 231 || !TEST_true(EVP_PKEY_assign_EC_KEY(pkey, eckey)) 232 /* fake key for negative testing */ 233 || !TEST_ptr(eckey_neg = EC_KEY_new_by_curve_name(nid)) 234 || !TEST_true(EC_KEY_generate_key(eckey_neg)) 235 || !TEST_ptr(pkey_neg = EVP_PKEY_new()) 236 || !TEST_false(EVP_PKEY_assign_EC_KEY(pkey_neg, NULL)) 237 || !TEST_true(EVP_PKEY_assign_EC_KEY(pkey_neg, eckey_neg))) 238 goto err; 239 240 if (!TEST_ptr(dup_pk = EVP_PKEY_dup(pkey)) 241 || !TEST_int_eq(EVP_PKEY_eq(pkey, dup_pk), 1)) 242 goto err; 243 244 temp = ECDSA_size(eckey); 245 246 if (!TEST_int_ge(temp, 0) 247 || !TEST_ptr(sig = OPENSSL_malloc(sig_len = (size_t)temp)) 248 /* create a signature */ 249 || !TEST_true(EVP_DigestSignInit(mctx, NULL, NULL, NULL, pkey)) 250 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 251 || !TEST_true(EVP_DigestSign(mctx, sig, &sig_len, tbs, sizeof(tbs))) 252 || !TEST_int_le(sig_len, ECDSA_size(eckey)) 253 || !TEST_true(EVP_MD_CTX_reset(mctx)) 254 /* negative test, verify with wrong key, 0 return */ 255 || !TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey_neg)) 256 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey_neg)) 257 || !TEST_int_eq(EVP_DigestVerify(mctx, sig, sig_len, tbs, sizeof(tbs)), 0) 258 || !TEST_true(EVP_MD_CTX_reset(mctx)) 259 /* negative test, verify with wrong signature length, -1 return */ 260 || !TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey)) 261 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 262 || !TEST_int_eq(EVP_DigestVerify(mctx, sig, sig_len - 1, tbs, sizeof(tbs)), -1) 263 || !TEST_true(EVP_MD_CTX_reset(mctx)) 264 /* positive test, verify with correct key, 1 return */ 265 || !TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey)) 266 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 267 || !TEST_int_eq(EVP_DigestVerify(mctx, sig, sig_len, tbs, sizeof(tbs)), 1) 268 || !TEST_true(EVP_MD_CTX_reset(mctx))) 269 goto err; 270 271 /* muck with the message, test it fails with 0 return */ 272 tbs[0] ^= 1; 273 if (!TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey)) 274 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 275 || !TEST_int_eq(EVP_DigestVerify(mctx, sig, sig_len, tbs, sizeof(tbs)), 0) 276 || !TEST_true(EVP_MD_CTX_reset(mctx))) 277 goto err; 278 /* un-muck and test it verifies */ 279 tbs[0] ^= 1; 280 if (!TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey)) 281 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 282 || !TEST_int_eq(EVP_DigestVerify(mctx, sig, sig_len, tbs, sizeof(tbs)), 1) 283 || !TEST_true(EVP_MD_CTX_reset(mctx))) 284 goto err; 285 286 /*- 287 * Muck with the ECDSA signature. The DER encoding is one of: 288 * - 30 LL 02 .. 289 * - 30 81 LL 02 .. 290 * 291 * - Sometimes this mucks with the high level DER sequence wrapper: 292 * in that case, DER-parsing of the whole signature should fail. 293 * 294 * - Sometimes this mucks with the DER-encoding of ECDSA.r: 295 * in that case, DER-parsing of ECDSA.r should fail. 296 * 297 * - Sometimes this mucks with the DER-encoding of ECDSA.s: 298 * in that case, DER-parsing of ECDSA.s should fail. 299 * 300 * - Sometimes this mucks with ECDSA.r: 301 * in that case, the signature verification should fail. 302 * 303 * - Sometimes this mucks with ECDSA.s: 304 * in that case, the signature verification should fail. 305 * 306 * The usual case is changing the integer value of ECDSA.r or ECDSA.s. 307 * Because the ratio of DER overhead to signature bytes is small. 308 * So most of the time it will be one of the last two cases. 309 * 310 * In any case, EVP_PKEY_verify should not return 1 for valid. 311 */ 312 offset = tbs[0] % sig_len; 313 dirt = tbs[1] ? tbs[1] : 1; 314 sig[offset] ^= dirt; 315 if (!TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey)) 316 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 317 || !TEST_int_ne(EVP_DigestVerify(mctx, sig, sig_len, tbs, sizeof(tbs)), 1) 318 || !TEST_true(EVP_MD_CTX_reset(mctx))) 319 goto err; 320 /* un-muck and test it verifies */ 321 sig[offset] ^= dirt; 322 if (!TEST_true(EVP_DigestVerifyInit(mctx, NULL, NULL, NULL, pkey)) 323 || (as == EVP_PKEY_SM2 && !set_sm2_id(mctx, pkey)) 324 || !TEST_int_eq(EVP_DigestVerify(mctx, sig, sig_len, tbs, sizeof(tbs)), 1) 325 || !TEST_true(EVP_MD_CTX_reset(mctx))) 326 goto err; 327 328 ret = 1; 329 err: 330 EVP_PKEY_free(pkey); 331 EVP_PKEY_free(pkey_neg); 332 EVP_PKEY_free(dup_pk); 333 EVP_MD_CTX_free(mctx); 334 OPENSSL_free(sig); 335 return ret; 336 } 337 338 static int test_builtin_as_ec(int n) 339 { 340 return test_builtin(n, EVP_PKEY_EC); 341 } 342 343 # ifndef OPENSSL_NO_SM2 344 static int test_builtin_as_sm2(int n) 345 { 346 return test_builtin(n, EVP_PKEY_SM2); 347 } 348 # endif 349 350 static int test_ecdsa_sig_NULL(void) 351 { 352 int ret; 353 unsigned int siglen; 354 unsigned char dgst[128] = { 0 }; 355 EC_KEY *eckey = NULL; 356 357 ret = TEST_ptr(eckey = EC_KEY_new_by_curve_name(NID_X9_62_prime256v1)) 358 && TEST_int_eq(EC_KEY_generate_key(eckey), 1) 359 && TEST_int_eq(ECDSA_sign(0, dgst, sizeof(dgst), NULL, &siglen, eckey), 1) 360 && TEST_int_gt(siglen, 0); 361 EC_KEY_free(eckey); 362 return ret; 363 } 364 365 #endif /* OPENSSL_NO_EC */ 366 367 int setup_tests(void) 368 { 369 #ifdef OPENSSL_NO_EC 370 TEST_note("Elliptic curves are disabled."); 371 #else 372 fake_rand = fake_rand_start(NULL); 373 if (fake_rand == NULL) 374 return 0; 375 376 /* get a list of all internal curves */ 377 crv_len = EC_get_builtin_curves(NULL, 0); 378 if (!TEST_ptr(curves = OPENSSL_malloc(sizeof(*curves) * crv_len)) 379 || !TEST_true(EC_get_builtin_curves(curves, crv_len))) { 380 fake_rand_finish(fake_rand); 381 return 0; 382 } 383 ADD_ALL_TESTS(test_builtin_as_ec, crv_len); 384 ADD_TEST(test_ecdsa_sig_NULL); 385 # ifndef OPENSSL_NO_SM2 386 ADD_ALL_TESTS(test_builtin_as_sm2, crv_len); 387 # endif 388 ADD_ALL_TESTS(x9_62_tests, OSSL_NELEM(ecdsa_cavs_kats)); 389 #endif 390 return 1; 391 } 392 393 void cleanup_tests(void) 394 { 395 #ifndef OPENSSL_NO_EC 396 fake_rand_finish(fake_rand); 397 OPENSSL_free(curves); 398 #endif 399 } 400