crypto/x509/x509_cmp.c

   1 /*
   2  * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the Apache License 2.0 (the "License").  You may not use
   5  * this file except in compliance with the License.  You can obtain a copy
   6  * in the file LICENSE in the source distribution or at
   7  * https://www.openssl.org/source/license.html
   8  */
   9
  10 #include <stdio.h>
  11 #include "internal/cryptlib.h"
  12 #include <openssl/asn1.h>
  13 #include <openssl/objects.h>
  14 #include <openssl/x509.h>
  15 #include <openssl/x509v3.h>
  16 #include <openssl/core_names.h>
  17 #include "crypto/x509.h"
  18
  19 int X509_issuer_and_serial_cmp(const X509 *a, const X509 *b)
  20 {
  21     int i;
  22     const X509_CINF *ai, *bi;
  23
  24     if (b == NULL)
  25         return a != NULL;
  26     if (a == NULL)
  27         return -1;
  28     ai = &a->cert_info;
  29     bi = &b->cert_info;
  30     i = ASN1_INTEGER_cmp(&ai->serialNumber, &bi->serialNumber);
  31     if (i != 0)
  32         return i < 0 ? -1 : 1;
  33     return X509_NAME_cmp(ai->issuer, bi->issuer);
  34 }
  35
  36 #ifndef OPENSSL_NO_MD5
  37 unsigned long X509_issuer_and_serial_hash(X509 *a)
  38 {
  39     unsigned long ret = 0;
  40     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
  41     unsigned char md[16];
  42     char *f;
  43
  44     if (ctx == NULL)
  45         goto err;
  46     f = X509_NAME_oneline(a->cert_info.issuer, NULL, 0);
  47     if (!EVP_DigestInit_ex(ctx, EVP_md5(), NULL))
  48         goto err;
  49     if (!EVP_DigestUpdate(ctx, (unsigned char *)f, strlen(f)))
  50         goto err;
  51     OPENSSL_free(f);
  52     if (!EVP_DigestUpdate
  53         (ctx, (unsigned char *)a->cert_info.serialNumber.data,
  54          (unsigned long)a->cert_info.serialNumber.length))
  55         goto err;
  56     if (!EVP_DigestFinal_ex(ctx, &(md[0]), NULL))
  57         goto err;
  58     ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
  59            ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
  60         ) & 0xffffffffL;
  61  err:
  62     EVP_MD_CTX_free(ctx);
  63     return ret;
  64 }
  65 #endif
  66
  67 int X509_issuer_name_cmp(const X509 *a, const X509 *b)
  68 {
  69     return X509_NAME_cmp(a->cert_info.issuer, b->cert_info.issuer);
  70 }
  71
  72 int X509_subject_name_cmp(const X509 *a, const X509 *b)
  73 {
  74     return X509_NAME_cmp(a->cert_info.subject, b->cert_info.subject);
  75 }
  76
  77 int X509_CRL_cmp(const X509_CRL *a, const X509_CRL *b)
  78 {
  79     return X509_NAME_cmp(a->crl.issuer, b->crl.issuer);
  80 }
  81
  82 int X509_CRL_match(const X509_CRL *a, const X509_CRL *b)
  83 {
  84     int rv;
  85
  86     if ((a->flags & EXFLAG_NO_FINGERPRINT) == 0
  87             && (b->flags & EXFLAG_NO_FINGERPRINT) == 0)
  88         rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
  89     else
  90         return -2;
  91
  92     return rv < 0 ? -1 : rv > 0;
  93 }
  94
  95 X509_NAME *X509_get_issuer_name(const X509 *a)
  96 {
  97     return a->cert_info.issuer;
  98 }
  99
 100 unsigned long X509_issuer_name_hash(X509 *x)
 101 {
 102     return X509_NAME_hash_ex(x->cert_info.issuer, NULL, NULL, NULL);
 103 }
 104
 105 #ifndef OPENSSL_NO_MD5
 106 unsigned long X509_issuer_name_hash_old(X509 *x)
 107 {
 108     return X509_NAME_hash_old(x->cert_info.issuer);
 109 }
 110 #endif
 111
 112 X509_NAME *X509_get_subject_name(const X509 *a)
 113 {
 114     return a->cert_info.subject;
 115 }
 116
 117 ASN1_INTEGER *X509_get_serialNumber(X509 *a)
 118 {
 119     return &a->cert_info.serialNumber;
 120 }
 121
 122 const ASN1_INTEGER *X509_get0_serialNumber(const X509 *a)
 123 {
 124     return &a->cert_info.serialNumber;
 125 }
 126
 127 unsigned long X509_subject_name_hash(X509 *x)
 128 {
 129     return X509_NAME_hash_ex(x->cert_info.subject, NULL, NULL, NULL);
 130 }
 131
 132 #ifndef OPENSSL_NO_MD5
 133 unsigned long X509_subject_name_hash_old(X509 *x)
 134 {
 135     return X509_NAME_hash_old(x->cert_info.subject);
 136 }
 137 #endif
 138
 139 /*
 140  * Compare two certificates: they must be identical for this to work. NB:
 141  * Although "cmp" operations are generally prototyped to take "const"
 142  * arguments (eg. for use in STACKs), the way X509 handling is - these
 143  * operations may involve ensuring the hashes are up-to-date and ensuring
 144  * certain cert information is cached. So this is the point where the
 145  * "depth-first" constification tree has to halt with an evil cast.
 146  */
 147 int X509_cmp(const X509 *a, const X509 *b)
 148 {
 149     int rv = 0;
 150
 151     if (a == b) /* for efficiency */
 152         return 0;
 153
 154     /* attempt to compute cert hash */
 155     (void)X509_check_purpose((X509 *)a, -1, 0);
 156     (void)X509_check_purpose((X509 *)b, -1, 0);
 157
 158     if ((a->ex_flags & EXFLAG_NO_FINGERPRINT) == 0
 159             && (b->ex_flags & EXFLAG_NO_FINGERPRINT) == 0)
 160         rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
 161     if (rv != 0)
 162         return rv < 0 ? -1 : 1;
 163
 164     /* Check for match against stored encoding too */
 165     if (!a->cert_info.enc.modified && !b->cert_info.enc.modified) {
 166         if (a->cert_info.enc.len < b->cert_info.enc.len)
 167             return -1;
 168         if (a->cert_info.enc.len > b->cert_info.enc.len)
 169             return 1;
 170         rv = memcmp(a->cert_info.enc.enc,
 171                     b->cert_info.enc.enc, a->cert_info.enc.len);
 172     }
 173     return rv < 0 ? -1 : rv > 0;
 174 }
 175
 176 int X509_add_cert_new(STACK_OF(X509) **sk, X509 *cert, int flags)
 177 {
 178     if (*sk == NULL
 179             && (*sk = sk_X509_new_null()) == NULL) {
 180         ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
 181         return 0;
 182     }
 183     return X509_add_cert(*sk, cert, flags);
 184 }
 185
 186 int X509_add_cert(STACK_OF(X509) *sk, X509 *cert, int flags)
 187 {
 188     if (sk == NULL) {
 189         ERR_raise(ERR_LIB_X509, ERR_R_PASSED_NULL_PARAMETER);
 190         return 0;
 191     }
 192     if ((flags & X509_ADD_FLAG_NO_DUP) != 0) {
 193         /*
 194          * not using sk_X509_set_cmp_func() and sk_X509_find()
 195          * because this re-orders the certs on the stack
 196          */
 197         int i;
 198
 199         for (i = 0; i < sk_X509_num(sk); i++) {
 200             if (X509_cmp(sk_X509_value(sk, i), cert) == 0)
 201                 return 1;
 202         }
 203     }
 204     if ((flags & X509_ADD_FLAG_NO_SS) != 0 && X509_self_signed(cert, 0))
 205         return 1;
 206     if (!sk_X509_insert(sk, cert,
 207                         (flags & X509_ADD_FLAG_PREPEND) != 0 ? 0 : -1)) {
 208         ERR_raise(ERR_LIB_X509, ERR_R_MALLOC_FAILURE);
 209         return 0;
 210     }
 211     if ((flags & X509_ADD_FLAG_UP_REF) != 0)
 212         (void)X509_up_ref(cert);
 213     return 1;
 214 }
 215
 216 int X509_add_certs(STACK_OF(X509) *sk, STACK_OF(X509) *certs, int flags)
 217 /* compiler would allow 'const' for the list of certs, yet they are up-ref'ed */
 218 {
 219     int n = sk_X509_num(certs); /* certs may be NULL */
 220     int i;
 221
 222     for (i = 0; i < n; i++) {
 223         int j = (flags & X509_ADD_FLAG_PREPEND) == 0 ? i : n - 1 - i;
 224         /* if prepend, add certs in reverse order to keep original order */
 225
 226         if (!X509_add_cert(sk, sk_X509_value(certs, j), flags))
 227             return 0;
 228     }
 229     return 1;
 230 }
 231
 232 int X509_NAME_cmp(const X509_NAME *a, const X509_NAME *b)
 233 {
 234     int ret;
 235
 236     if (b == NULL)
 237         return a != NULL;
 238     if (a == NULL)
 239         return -1;
 240
 241     /* Ensure canonical encoding is present and up to date */
 242     if (!a->canon_enc || a->modified) {
 243         ret = i2d_X509_NAME((X509_NAME *)a, NULL);
 244         if (ret < 0)
 245             return -2;
 246     }
 247
 248     if (!b->canon_enc || b->modified) {
 249         ret = i2d_X509_NAME((X509_NAME *)b, NULL);
 250         if (ret < 0)
 251             return -2;
 252     }
 253
 254     ret = a->canon_enclen - b->canon_enclen;
 255     if (ret == 0 && a->canon_enclen != 0)
 256         ret = memcmp(a->canon_enc, b->canon_enc, a->canon_enclen);
 257
 258     return ret < 0 ? -1 : ret > 0;
 259 }
 260
 261 unsigned long X509_NAME_hash_ex(const X509_NAME *x, OSSL_LIB_CTX *libctx,
 262                                 const char *propq, int *ok)
 263 {
 264     unsigned long ret = 0;
 265     unsigned char md[SHA_DIGEST_LENGTH];
 266     EVP_MD *sha1 = EVP_MD_fetch(libctx, "SHA1", propq);
 267
 268     /* Make sure X509_NAME structure contains valid cached encoding */
 269     i2d_X509_NAME(x, NULL);
 270     if (ok != NULL)
 271         *ok = 0;
 272     if (sha1 != NULL
 273         && EVP_Digest(x->canon_enc, x->canon_enclen, md, NULL, sha1, NULL)) {
 274         ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
 275                ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
 276                ) & 0xffffffffL;
 277         if (ok != NULL)
 278             *ok = 1;
 279     }
 280     EVP_MD_free(sha1);
 281     return ret;
 282 }
 283
 284 #ifndef OPENSSL_NO_MD5
 285 /*
 286  * I now DER encode the name and hash it.  Since I cache the DER encoding,
 287  * this is reasonably efficient.
 288  */
 289 unsigned long X509_NAME_hash_old(const X509_NAME *x)
 290 {
 291     EVP_MD *md5 = EVP_MD_fetch(NULL, OSSL_DIGEST_NAME_MD5, "-fips");
 292     EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
 293     unsigned long ret = 0;
 294     unsigned char md[16];
 295
 296     if (md5 == NULL || md_ctx == NULL)
 297         goto end;
 298
 299     /* Make sure X509_NAME structure contains valid cached encoding */
 300     i2d_X509_NAME(x, NULL);
 301     if (EVP_DigestInit_ex(md_ctx, md5, NULL)
 302         && EVP_DigestUpdate(md_ctx, x->bytes->data, x->bytes->length)
 303         && EVP_DigestFinal_ex(md_ctx, md, NULL))
 304         ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
 305                ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
 306             ) & 0xffffffffL;
 307
 308  end:
 309     EVP_MD_CTX_free(md_ctx);
 310     EVP_MD_free(md5);
 311
 312     return ret;
 313 }
 314 #endif
 315
 316 /* Search a stack of X509 for a match */
 317 X509 *X509_find_by_issuer_and_serial(STACK_OF(X509) *sk, const X509_NAME *name,
 318                                      const ASN1_INTEGER *serial)
 319 {
 320     int i;
 321     X509 x, *x509 = NULL;
 322
 323     if (!sk)
 324         return NULL;
 325
 326     x.cert_info.serialNumber = *serial;
 327     x.cert_info.issuer = (X509_NAME *)name; /* won't modify it */
 328
 329     for (i = 0; i < sk_X509_num(sk); i++) {
 330         x509 = sk_X509_value(sk, i);
 331         if (X509_issuer_and_serial_cmp(x509, &x) == 0)
 332             return x509;
 333     }
 334     return NULL;
 335 }
 336
 337 X509 *X509_find_by_subject(STACK_OF(X509) *sk, const X509_NAME *name)
 338 {
 339     X509 *x509;
 340     int i;
 341
 342     for (i = 0; i < sk_X509_num(sk); i++) {
 343         x509 = sk_X509_value(sk, i);
 344         if (X509_NAME_cmp(X509_get_subject_name(x509), name) == 0)
 345             return x509;
 346     }
 347     return NULL;
 348 }
 349
 350 EVP_PKEY *X509_get0_pubkey(const X509 *x)
 351 {
 352     if (x == NULL)
 353         return NULL;
 354     return X509_PUBKEY_get0(x->cert_info.key);
 355 }
 356
 357 EVP_PKEY *X509_get_pubkey(X509 *x)
 358 {
 359     if (x == NULL)
 360         return NULL;
 361     return X509_PUBKEY_get(x->cert_info.key);
 362 }
 363
 364 int X509_check_private_key(const X509 *x, const EVP_PKEY *k)
 365 {
 366     const EVP_PKEY *xk;
 367     int ret;
 368
 369     xk = X509_get0_pubkey(x);
 370
 371     if (xk)
 372         ret = EVP_PKEY_eq(xk, k);
 373     else
 374         ret = -2;
 375
 376     switch (ret) {
 377     case 1:
 378         break;
 379     case 0:
 380         ERR_raise(ERR_LIB_X509, X509_R_KEY_VALUES_MISMATCH);
 381         break;
 382     case -1:
 383         ERR_raise(ERR_LIB_X509, X509_R_KEY_TYPE_MISMATCH);
 384         break;
 385     case -2:
 386         ERR_raise(ERR_LIB_X509, X509_R_UNKNOWN_KEY_TYPE);
 387     }
 388     if (ret > 0)
 389         return 1;
 390     return 0;
 391 }
 392
 393 /*
 394  * Check a suite B algorithm is permitted: pass in a public key and the NID
 395  * of its signature (or 0 if no signature). The pflags is a pointer to a
 396  * flags field which must contain the suite B verification flags.
 397  */
 398
 399 #ifndef OPENSSL_NO_EC
 400
 401 static int check_suite_b(EVP_PKEY *pkey, int sign_nid, unsigned long *pflags)
 402 {
 403     char curve_name[80];
 404     size_t curve_name_len;
 405     int curve_nid;
 406
 407     if (pkey == NULL || !EVP_PKEY_is_a(pkey, "EC"))
 408         return X509_V_ERR_SUITE_B_INVALID_ALGORITHM;
 409
 410     if (!EVP_PKEY_get_group_name(pkey, curve_name, sizeof(curve_name),
 411                                  &curve_name_len))
 412         return X509_V_ERR_SUITE_B_INVALID_CURVE;
 413
 414     curve_nid = OBJ_txt2nid(curve_name);
 415     /* Check curve is consistent with LOS */
 416     if (curve_nid == NID_secp384r1) { /* P-384 */
 417         /*
 418          * Check signature algorithm is consistent with curve.
 419          */
 420         if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA384)
 421             return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
 422         if (!(*pflags & X509_V_FLAG_SUITEB_192_LOS))
 423             return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
 424         /* If we encounter P-384 we cannot use P-256 later */
 425         *pflags &= ~X509_V_FLAG_SUITEB_128_LOS_ONLY;
 426     } else if (curve_nid == NID_X9_62_prime256v1) { /* P-256 */
 427         if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA256)
 428             return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
 429         if (!(*pflags & X509_V_FLAG_SUITEB_128_LOS_ONLY))
 430             return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
 431     } else {
 432         return X509_V_ERR_SUITE_B_INVALID_CURVE;
 433     }
 434     return X509_V_OK;
 435 }
 436
 437 int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
 438                             unsigned long flags)
 439 {
 440     int rv, i, sign_nid;
 441     EVP_PKEY *pk;
 442     unsigned long tflags = flags;
 443
 444     if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
 445         return X509_V_OK;
 446
 447     /* If no EE certificate passed in must be first in chain */
 448     if (x == NULL) {
 449         x = sk_X509_value(chain, 0);
 450         i = 1;
 451     } else {
 452         i = 0;
 453     }
 454     pk = X509_get0_pubkey(x);
 455
 456     /*
 457      * With DANE-EE(3) success, or DANE-EE(3)/PKIX-EE(1) failure we don't build
 458      * a chain all, just report trust success or failure, but must also report
 459      * Suite-B errors if applicable.  This is indicated via a NULL chain
 460      * pointer.  All we need to do is check the leaf key algorithm.
 461      */
 462     if (chain == NULL)
 463         return check_suite_b(pk, -1, &tflags);
 464
 465     if (X509_get_version(x) != 2) {
 466         rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
 467         /* Correct error depth */
 468         i = 0;
 469         goto end;
 470     }
 471
 472     /* Check EE key only */
 473     rv = check_suite_b(pk, -1, &tflags);
 474     if (rv != X509_V_OK) {
 475         /* Correct error depth */
 476         i = 0;
 477         goto end;
 478     }
 479     for (; i < sk_X509_num(chain); i++) {
 480         sign_nid = X509_get_signature_nid(x);
 481         x = sk_X509_value(chain, i);
 482         if (X509_get_version(x) != 2) {
 483             rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
 484             goto end;
 485         }
 486         pk = X509_get0_pubkey(x);
 487         rv = check_suite_b(pk, sign_nid, &tflags);
 488         if (rv != X509_V_OK)
 489             goto end;
 490     }
 491
 492     /* Final check: root CA signature */
 493     rv = check_suite_b(pk, X509_get_signature_nid(x), &tflags);
 494  end:
 495     if (rv != X509_V_OK) {
 496         /* Invalid signature or LOS errors are for previous cert */
 497         if ((rv == X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM
 498              || rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED) && i)
 499             i--;
 500         /*
 501          * If we have LOS error and flags changed then we are signing P-384
 502          * with P-256. Use more meaningful error.
 503          */
 504         if (rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED && flags != tflags)
 505             rv = X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256;
 506         if (perror_depth)
 507             *perror_depth = i;
 508     }
 509     return rv;
 510 }
 511
 512 int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
 513 {
 514     int sign_nid;
 515     if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
 516         return X509_V_OK;
 517     sign_nid = OBJ_obj2nid(crl->crl.sig_alg.algorithm);
 518     return check_suite_b(pk, sign_nid, &flags);
 519 }
 520
 521 #else
 522 int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
 523                             unsigned long flags)
 524 {
 525     return 0;
 526 }
 527
 528 int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
 529 {
 530     return 0;
 531 }
 532
 533 #endif
 534 /*
 535  * Not strictly speaking an "up_ref" as a STACK doesn't have a reference
 536  * count but it has the same effect by duping the STACK and upping the ref of
 537  * each X509 structure.
 538  */
 539 STACK_OF(X509) *X509_chain_up_ref(STACK_OF(X509) *chain)
 540 {
 541     STACK_OF(X509) *ret;
 542     int i;
 543     ret = sk_X509_dup(chain);
 544     if (ret == NULL)
 545         return NULL;
 546     for (i = 0; i < sk_X509_num(ret); i++) {
 547         X509 *x = sk_X509_value(ret, i);
 548         if (!X509_up_ref(x))
 549             goto err;
 550     }
 551     return ret;
 552  err:
 553     while (i-- > 0)
 554         X509_free(sk_X509_value(ret, i));
 555     sk_X509_free(ret);
 556     return NULL;
 557 }