crypto/x509/x509_cmp.c

   1 /*
   2  * Copyright 1995-2018 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 "internal/x509_int.h"
  17
  18 int X509_issuer_and_serial_cmp(const X509 *a, const X509 *b)
  19 {
  20     int i;
  21     const X509_CINF *ai, *bi;
  22
  23     ai = &a->cert_info;
  24     bi = &b->cert_info;
  25     i = ASN1_INTEGER_cmp(&ai->serialNumber, &bi->serialNumber);
  26     if (i)
  27         return i;
  28     return X509_NAME_cmp(ai->issuer, bi->issuer);
  29 }
  30
  31 #ifndef OPENSSL_NO_MD5
  32 unsigned long X509_issuer_and_serial_hash(X509 *a)
  33 {
  34     unsigned long ret = 0;
  35     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
  36     unsigned char md[16];
  37     char *f;
  38
  39     if (ctx == NULL)
  40         goto err;
  41     f = X509_NAME_oneline(a->cert_info.issuer, NULL, 0);
  42     if (!EVP_DigestInit_ex(ctx, EVP_md5(), NULL))
  43         goto err;
  44     if (!EVP_DigestUpdate(ctx, (unsigned char *)f, strlen(f)))
  45         goto err;
  46     OPENSSL_free(f);
  47     if (!EVP_DigestUpdate
  48         (ctx, (unsigned char *)a->cert_info.serialNumber.data,
  49          (unsigned long)a->cert_info.serialNumber.length))
  50         goto err;
  51     if (!EVP_DigestFinal_ex(ctx, &(md[0]), NULL))
  52         goto err;
  53     ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
  54            ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
  55         ) & 0xffffffffL;
  56  err:
  57     EVP_MD_CTX_free(ctx);
  58     return ret;
  59 }
  60 #endif
  61
  62 int X509_issuer_name_cmp(const X509 *a, const X509 *b)
  63 {
  64     return X509_NAME_cmp(a->cert_info.issuer, b->cert_info.issuer);
  65 }
  66
  67 int X509_subject_name_cmp(const X509 *a, const X509 *b)
  68 {
  69     return X509_NAME_cmp(a->cert_info.subject, b->cert_info.subject);
  70 }
  71
  72 int X509_CRL_cmp(const X509_CRL *a, const X509_CRL *b)
  73 {
  74     return X509_NAME_cmp(a->crl.issuer, b->crl.issuer);
  75 }
  76
  77 int X509_CRL_match(const X509_CRL *a, const X509_CRL *b)
  78 {
  79     return memcmp(a->sha1_hash, b->sha1_hash, 20);
  80 }
  81
  82 X509_NAME *X509_get_issuer_name(const X509 *a)
  83 {
  84     return a->cert_info.issuer;
  85 }
  86
  87 unsigned long X509_issuer_name_hash(X509 *x)
  88 {
  89     return X509_NAME_hash(x->cert_info.issuer);
  90 }
  91
  92 #ifndef OPENSSL_NO_MD5
  93 unsigned long X509_issuer_name_hash_old(X509 *x)
  94 {
  95     return X509_NAME_hash_old(x->cert_info.issuer);
  96 }
  97 #endif
  98
  99 X509_NAME *X509_get_subject_name(const X509 *a)
 100 {
 101     return a->cert_info.subject;
 102 }
 103
 104 ASN1_INTEGER *X509_get_serialNumber(X509 *a)
 105 {
 106     return &a->cert_info.serialNumber;
 107 }
 108
 109 const ASN1_INTEGER *X509_get0_serialNumber(const X509 *a)
 110 {
 111     return &a->cert_info.serialNumber;
 112 }
 113
 114 unsigned long X509_subject_name_hash(X509 *x)
 115 {
 116     return X509_NAME_hash(x->cert_info.subject);
 117 }
 118
 119 #ifndef OPENSSL_NO_MD5
 120 unsigned long X509_subject_name_hash_old(X509 *x)
 121 {
 122     return X509_NAME_hash_old(x->cert_info.subject);
 123 }
 124 #endif
 125
 126 /*
 127  * Compare two certificates: they must be identical for this to work. NB:
 128  * Although "cmp" operations are generally prototyped to take "const"
 129  * arguments (eg. for use in STACKs), the way X509 handling is - these
 130  * operations may involve ensuring the hashes are up-to-date and ensuring
 131  * certain cert information is cached. So this is the point where the
 132  * "depth-first" constification tree has to halt with an evil cast.
 133  */
 134 int X509_cmp(const X509 *a, const X509 *b)
 135 {
 136     int rv;
 137     /* ensure hash is valid */
 138     X509_check_purpose((X509 *)a, -1, 0);
 139     X509_check_purpose((X509 *)b, -1, 0);
 140
 141     rv = memcmp(a->sha1_hash, b->sha1_hash, SHA_DIGEST_LENGTH);
 142     if (rv)
 143         return rv;
 144     /* Check for match against stored encoding too */
 145     if (!a->cert_info.enc.modified && !b->cert_info.enc.modified) {
 146         if (a->cert_info.enc.len < b->cert_info.enc.len)
 147             return -1;
 148         if (a->cert_info.enc.len > b->cert_info.enc.len)
 149             return 1;
 150         return memcmp(a->cert_info.enc.enc, b->cert_info.enc.enc,
 151                       a->cert_info.enc.len);
 152     }
 153     return rv;
 154 }
 155
 156 int X509_NAME_cmp(const X509_NAME *a, const X509_NAME *b)
 157 {
 158     int ret;
 159
 160     /* Ensure canonical encoding is present and up to date */
 161
 162     if (!a->canon_enc || a->modified) {
 163         ret = i2d_X509_NAME((X509_NAME *)a, NULL);
 164         if (ret < 0)
 165             return -2;
 166     }
 167
 168     if (!b->canon_enc || b->modified) {
 169         ret = i2d_X509_NAME((X509_NAME *)b, NULL);
 170         if (ret < 0)
 171             return -2;
 172     }
 173
 174     ret = a->canon_enclen - b->canon_enclen;
 175
 176     if (ret != 0 || a->canon_enclen == 0)
 177         return ret;
 178
 179     return memcmp(a->canon_enc, b->canon_enc, a->canon_enclen);
 180
 181 }
 182
 183 unsigned long X509_NAME_hash(X509_NAME *x)
 184 {
 185     unsigned long ret = 0;
 186     unsigned char md[SHA_DIGEST_LENGTH];
 187
 188     /* Make sure X509_NAME structure contains valid cached encoding */
 189     i2d_X509_NAME(x, NULL);
 190     if (!EVP_Digest(x->canon_enc, x->canon_enclen, md, NULL, EVP_sha1(),
 191                     NULL))
 192         return 0;
 193
 194     ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
 195            ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
 196         ) & 0xffffffffL;
 197     return ret;
 198 }
 199
 200 #ifndef OPENSSL_NO_MD5
 201 /*
 202  * I now DER encode the name and hash it.  Since I cache the DER encoding,
 203  * this is reasonably efficient.
 204  */
 205
 206 unsigned long X509_NAME_hash_old(X509_NAME *x)
 207 {
 208     EVP_MD_CTX *md_ctx = EVP_MD_CTX_new();
 209     unsigned long ret = 0;
 210     unsigned char md[16];
 211
 212     if (md_ctx == NULL)
 213         return ret;
 214
 215     /* Make sure X509_NAME structure contains valid cached encoding */
 216     i2d_X509_NAME(x, NULL);
 217     EVP_MD_CTX_set_flags(md_ctx, EVP_MD_CTX_FLAG_NON_FIPS_ALLOW);
 218     if (EVP_DigestInit_ex(md_ctx, EVP_md5(), NULL)
 219         && EVP_DigestUpdate(md_ctx, x->bytes->data, x->bytes->length)
 220         && EVP_DigestFinal_ex(md_ctx, md, NULL))
 221         ret = (((unsigned long)md[0]) | ((unsigned long)md[1] << 8L) |
 222                ((unsigned long)md[2] << 16L) | ((unsigned long)md[3] << 24L)
 223             ) & 0xffffffffL;
 224     EVP_MD_CTX_free(md_ctx);
 225
 226     return ret;
 227 }
 228 #endif
 229
 230 /* Search a stack of X509 for a match */
 231 X509 *X509_find_by_issuer_and_serial(STACK_OF(X509) *sk, X509_NAME *name,
 232                                      ASN1_INTEGER *serial)
 233 {
 234     int i;
 235     X509 x, *x509 = NULL;
 236
 237     if (!sk)
 238         return NULL;
 239
 240     x.cert_info.serialNumber = *serial;
 241     x.cert_info.issuer = name;
 242
 243     for (i = 0; i < sk_X509_num(sk); i++) {
 244         x509 = sk_X509_value(sk, i);
 245         if (X509_issuer_and_serial_cmp(x509, &x) == 0)
 246             return x509;
 247     }
 248     return NULL;
 249 }
 250
 251 X509 *X509_find_by_subject(STACK_OF(X509) *sk, X509_NAME *name)
 252 {
 253     X509 *x509;
 254     int i;
 255
 256     for (i = 0; i < sk_X509_num(sk); i++) {
 257         x509 = sk_X509_value(sk, i);
 258         if (X509_NAME_cmp(X509_get_subject_name(x509), name) == 0)
 259             return x509;
 260     }
 261     return NULL;
 262 }
 263
 264 EVP_PKEY *X509_get0_pubkey(const X509 *x)
 265 {
 266     if (x == NULL)
 267         return NULL;
 268     return X509_PUBKEY_get0(x->cert_info.key);
 269 }
 270
 271 EVP_PKEY *X509_get_pubkey(X509 *x)
 272 {
 273     if (x == NULL)
 274         return NULL;
 275     return X509_PUBKEY_get(x->cert_info.key);
 276 }
 277
 278 int X509_check_private_key(const X509 *x, const EVP_PKEY *k)
 279 {
 280     const EVP_PKEY *xk;
 281     int ret;
 282
 283     xk = X509_get0_pubkey(x);
 284
 285     if (xk)
 286         ret = EVP_PKEY_cmp(xk, k);
 287     else
 288         ret = -2;
 289
 290     switch (ret) {
 291     case 1:
 292         break;
 293     case 0:
 294         X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_KEY_VALUES_MISMATCH);
 295         break;
 296     case -1:
 297         X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_KEY_TYPE_MISMATCH);
 298         break;
 299     case -2:
 300         X509err(X509_F_X509_CHECK_PRIVATE_KEY, X509_R_UNKNOWN_KEY_TYPE);
 301     }
 302     if (ret > 0)
 303         return 1;
 304     return 0;
 305 }
 306
 307 /*
 308  * Check a suite B algorithm is permitted: pass in a public key and the NID
 309  * of its signature (or 0 if no signature). The pflags is a pointer to a
 310  * flags field which must contain the suite B verification flags.
 311  */
 312
 313 #ifndef OPENSSL_NO_EC
 314
 315 static int check_suite_b(EVP_PKEY *pkey, int sign_nid, unsigned long *pflags)
 316 {
 317     const EC_GROUP *grp = NULL;
 318     int curve_nid;
 319     if (pkey && EVP_PKEY_id(pkey) == EVP_PKEY_EC)
 320         grp = EC_KEY_get0_group(EVP_PKEY_get0_EC_KEY(pkey));
 321     if (!grp)
 322         return X509_V_ERR_SUITE_B_INVALID_ALGORITHM;
 323     curve_nid = EC_GROUP_get_curve_name(grp);
 324     /* Check curve is consistent with LOS */
 325     if (curve_nid == NID_secp384r1) { /* P-384 */
 326         /*
 327          * Check signature algorithm is consistent with curve.
 328          */
 329         if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA384)
 330             return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
 331         if (!(*pflags & X509_V_FLAG_SUITEB_192_LOS))
 332             return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
 333         /* If we encounter P-384 we cannot use P-256 later */
 334         *pflags &= ~X509_V_FLAG_SUITEB_128_LOS_ONLY;
 335     } else if (curve_nid == NID_X9_62_prime256v1) { /* P-256 */
 336         if (sign_nid != -1 && sign_nid != NID_ecdsa_with_SHA256)
 337             return X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM;
 338         if (!(*pflags & X509_V_FLAG_SUITEB_128_LOS_ONLY))
 339             return X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED;
 340     } else
 341         return X509_V_ERR_SUITE_B_INVALID_CURVE;
 342
 343     return X509_V_OK;
 344 }
 345
 346 int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
 347                             unsigned long flags)
 348 {
 349     int rv, i, sign_nid;
 350     EVP_PKEY *pk;
 351     unsigned long tflags = flags;
 352
 353     if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
 354         return X509_V_OK;
 355
 356     /* If no EE certificate passed in must be first in chain */
 357     if (x == NULL) {
 358         x = sk_X509_value(chain, 0);
 359         i = 1;
 360     } else
 361         i = 0;
 362
 363     pk = X509_get0_pubkey(x);
 364
 365     /*
 366      * With DANE-EE(3) success, or DANE-EE(3)/PKIX-EE(1) failure we don't build
 367      * a chain all, just report trust success or failure, but must also report
 368      * Suite-B errors if applicable.  This is indicated via a NULL chain
 369      * pointer.  All we need to do is check the leaf key algorithm.
 370      */
 371     if (chain == NULL)
 372         return check_suite_b(pk, -1, &tflags);
 373
 374     if (X509_get_version(x) != 2) {
 375         rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
 376         /* Correct error depth */
 377         i = 0;
 378         goto end;
 379     }
 380
 381     /* Check EE key only */
 382     rv = check_suite_b(pk, -1, &tflags);
 383     if (rv != X509_V_OK) {
 384         /* Correct error depth */
 385         i = 0;
 386         goto end;
 387     }
 388     for (; i < sk_X509_num(chain); i++) {
 389         sign_nid = X509_get_signature_nid(x);
 390         x = sk_X509_value(chain, i);
 391         if (X509_get_version(x) != 2) {
 392             rv = X509_V_ERR_SUITE_B_INVALID_VERSION;
 393             goto end;
 394         }
 395         pk = X509_get0_pubkey(x);
 396         rv = check_suite_b(pk, sign_nid, &tflags);
 397         if (rv != X509_V_OK)
 398             goto end;
 399     }
 400
 401     /* Final check: root CA signature */
 402     rv = check_suite_b(pk, X509_get_signature_nid(x), &tflags);
 403  end:
 404     if (rv != X509_V_OK) {
 405         /* Invalid signature or LOS errors are for previous cert */
 406         if ((rv == X509_V_ERR_SUITE_B_INVALID_SIGNATURE_ALGORITHM
 407              || rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED) && i)
 408             i--;
 409         /*
 410          * If we have LOS error and flags changed then we are signing P-384
 411          * with P-256. Use more meaningful error.
 412          */
 413         if (rv == X509_V_ERR_SUITE_B_LOS_NOT_ALLOWED && flags != tflags)
 414             rv = X509_V_ERR_SUITE_B_CANNOT_SIGN_P_384_WITH_P_256;
 415         if (perror_depth)
 416             *perror_depth = i;
 417     }
 418     return rv;
 419 }
 420
 421 int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
 422 {
 423     int sign_nid;
 424     if (!(flags & X509_V_FLAG_SUITEB_128_LOS))
 425         return X509_V_OK;
 426     sign_nid = OBJ_obj2nid(crl->crl.sig_alg.algorithm);
 427     return check_suite_b(pk, sign_nid, &flags);
 428 }
 429
 430 #else
 431 int X509_chain_check_suiteb(int *perror_depth, X509 *x, STACK_OF(X509) *chain,
 432                             unsigned long flags)
 433 {
 434     return 0;
 435 }
 436
 437 int X509_CRL_check_suiteb(X509_CRL *crl, EVP_PKEY *pk, unsigned long flags)
 438 {
 439     return 0;
 440 }
 441
 442 #endif
 443 /*
 444  * Not strictly speaking an "up_ref" as a STACK doesn't have a reference
 445  * count but it has the same effect by duping the STACK and upping the ref of
 446  * each X509 structure.
 447  */
 448 STACK_OF(X509) *X509_chain_up_ref(STACK_OF(X509) *chain)
 449 {
 450     STACK_OF(X509) *ret;
 451     int i;
 452     ret = sk_X509_dup(chain);
 453     if (ret == NULL)
 454         return NULL;
 455     for (i = 0; i < sk_X509_num(ret); i++) {
 456         X509 *x = sk_X509_value(ret, i);
 457         if (!X509_up_ref(x))
 458             goto err;
 459     }
 460     return ret;
 461  err:
 462     while (i-- > 0)
 463         X509_free (sk_X509_value(ret, i));
 464     sk_X509_free(ret);
 465     return NULL;
 466 }