test/ct_test.c

   1 /*
   2  * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 <ctype.h>
  11 #include <math.h>
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <string.h>
  15
  16 #include <openssl/ct.h>
  17 #include <openssl/err.h>
  18 #include <openssl/pem.h>
  19 #include <openssl/x509.h>
  20 #include <openssl/x509v3.h>
  21 #include "testutil.h"
  22 #include "test_main_custom.h"
  23
  24 #ifndef OPENSSL_NO_CT
  25 /* Used when declaring buffers to read text files into */
  26 #define CT_TEST_MAX_FILE_SIZE 8096
  27
  28 static char *certs_dir = NULL;
  29 static char *ct_dir = NULL;
  30
  31 typedef struct ct_test_fixture {
  32     const char *test_case_name;
  33     /* The current time in milliseconds */
  34     uint64_t epoch_time_in_ms;
  35     /* The CT log store to use during tests */
  36     CTLOG_STORE* ctlog_store;
  37     /* Set the following to test handling of SCTs in X509 certificates */
  38     const char *certs_dir;
  39     char *certificate_file;
  40     char *issuer_file;
  41     /* Expected number of SCTs */
  42     int expected_sct_count;
  43     /* Expected number of valid SCTS */
  44     int expected_valid_sct_count;
  45     /* Set the following to test handling of SCTs in TLS format */
  46     const unsigned char *tls_sct_list;
  47     size_t tls_sct_list_len;
  48     STACK_OF(SCT) *sct_list;
  49     /*
  50      * A file to load the expected SCT text from.
  51      * This text will be compared to the actual text output during the test.
  52      * A maximum of |CT_TEST_MAX_FILE_SIZE| bytes will be read of this file.
  53      */
  54     const char *sct_dir;
  55     const char *sct_text_file;
  56     /* Whether to test the validity of the SCT(s) */
  57     int test_validity;
  58 } CT_TEST_FIXTURE;
  59
  60 static CT_TEST_FIXTURE set_up(const char *const test_case_name)
  61 {
  62     CT_TEST_FIXTURE fixture;
  63     int setup_ok = 1;
  64
  65     memset(&fixture, 0, sizeof(fixture));
  66
  67     fixture.test_case_name = test_case_name;
  68     fixture.epoch_time_in_ms = 1473269626000; /* Sep 7 17:33:46 2016 GMT */
  69     fixture.ctlog_store = CTLOG_STORE_new();
  70
  71     if (fixture.ctlog_store == NULL) {
  72         setup_ok = 0;
  73         fprintf(stderr, "Failed to create a new CT log store\n");
  74         goto end;
  75     }
  76
  77     if (CTLOG_STORE_load_default_file(fixture.ctlog_store) != 1) {
  78         setup_ok = 0;
  79         fprintf(stderr, "Failed to load CT log list\n");
  80         goto end;
  81     }
  82
  83 end:
  84     if (!setup_ok) {
  85         CTLOG_STORE_free(fixture.ctlog_store);
  86         exit(EXIT_FAILURE);
  87     }
  88     return fixture;
  89 }
  90
  91 static void tear_down(CT_TEST_FIXTURE fixture)
  92 {
  93     CTLOG_STORE_free(fixture.ctlog_store);
  94     SCT_LIST_free(fixture.sct_list);
  95 }
  96
  97 static char *mk_file_path(const char *dir, const char *file)
  98 {
  99     char *full_file = NULL;
 100     size_t full_file_l = 0;
 101     const char *sep = "";
 102 #ifndef OPENSSL_SYS_VMS
 103     sep = "/";
 104 #endif
 105
 106     full_file_l = strlen(dir) + strlen(sep) + strlen(file) + 1;
 107     full_file = OPENSSL_zalloc(full_file_l);
 108     if (full_file != NULL) {
 109         OPENSSL_strlcpy(full_file, dir, full_file_l);
 110         OPENSSL_strlcat(full_file, sep, full_file_l);
 111         OPENSSL_strlcat(full_file, file, full_file_l);
 112     }
 113
 114     return full_file;
 115 }
 116
 117 static X509 *load_pem_cert(const char *dir, const char *file)
 118 {
 119     X509 *cert = NULL;
 120     char *file_path = mk_file_path(dir, file);
 121
 122     if (file_path != NULL) {
 123         BIO *cert_io = BIO_new_file(file_path, "r");
 124         OPENSSL_free(file_path);
 125
 126         if (cert_io != NULL)
 127             cert = PEM_read_bio_X509(cert_io, NULL, NULL, NULL);
 128
 129         BIO_free(cert_io);
 130     }
 131     return cert;
 132 }
 133
 134 static int read_text_file(const char *dir, const char *file,
 135                           char *buffer, int buffer_length)
 136 {
 137     int result = -1;
 138     char *file_path = mk_file_path(dir, file);
 139
 140     if (file_path != NULL) {
 141         BIO *file_io = BIO_new_file(file_path, "r");
 142         OPENSSL_free(file_path);
 143
 144         if (file_io != NULL) {
 145             result = BIO_read(file_io, buffer, buffer_length);
 146             BIO_free(file_io);
 147         }
 148     }
 149
 150     return result;
 151 }
 152
 153 static int compare_sct_list_printout(STACK_OF(SCT) *sct,
 154     const char *expected_output)
 155 {
 156     BIO *text_buffer = NULL;
 157     char *actual_output = NULL;
 158     int result = 1;
 159
 160     text_buffer = BIO_new(BIO_s_mem());
 161     if (text_buffer == NULL) {
 162         fprintf(stderr, "Unable to allocate buffer\n");
 163         goto end;
 164     }
 165
 166     SCT_LIST_print(sct, text_buffer, 0, "\n", NULL);
 167
 168     /* Append null terminator because we're about to use the buffer contents
 169     * as a string. */
 170     if (BIO_write(text_buffer, "\0", 1) != 1) {
 171         fprintf(stderr, "Failed to append null terminator to SCT text\n");
 172         goto end;
 173     }
 174
 175     BIO_get_mem_data(text_buffer, &actual_output);
 176     result = strcmp(actual_output, expected_output);
 177
 178     if (result != 0) {
 179         fprintf(stderr,
 180             "Expected SCT printout:\n%s\nActual SCT printout:\n%s\n",
 181             expected_output, actual_output);
 182     }
 183
 184 end:
 185     BIO_free(text_buffer);
 186     return result;
 187 }
 188
 189 static int compare_extension_printout(X509_EXTENSION *extension,
 190                                       const char *expected_output)
 191 {
 192     BIO *text_buffer = NULL;
 193     char *actual_output = NULL;
 194     int result = 1;
 195
 196     text_buffer = BIO_new(BIO_s_mem());
 197     if (text_buffer == NULL) {
 198         fprintf(stderr, "Unable to allocate buffer\n");
 199         goto end;
 200     }
 201
 202     if (!X509V3_EXT_print(text_buffer, extension, X509V3_EXT_DEFAULT, 0)) {
 203         fprintf(stderr, "Failed to print extension\n");
 204         goto end;
 205     }
 206
 207     /* Append null terminator because we're about to use the buffer contents
 208      * as a string. */
 209     if (BIO_write(text_buffer, "\0", 1) != 1) {
 210         fprintf(stderr,
 211                 "Failed to append null terminator to extension text\n");
 212         goto end;
 213     }
 214
 215     BIO_get_mem_data(text_buffer, &actual_output);
 216     result = strcmp(actual_output, expected_output);
 217
 218     if (result != 0) {
 219         fprintf(stderr,
 220                 "Expected SCT printout:\n%s\nActual SCT printout:\n%s\n",
 221                 expected_output, actual_output);
 222     }
 223
 224 end:
 225     BIO_free(text_buffer);
 226     return result;
 227 }
 228
 229 static int assert_validity(CT_TEST_FIXTURE fixture,
 230                            STACK_OF(SCT) *scts,
 231                            CT_POLICY_EVAL_CTX *policy_ctx) {
 232     int invalid_sct_count = 0;
 233     int valid_sct_count = 0;
 234     int i;
 235
 236     if (SCT_LIST_validate(scts, policy_ctx) < 0) {
 237         fprintf(stderr, "Error verifying SCTs\n");
 238         return 0;
 239     }
 240
 241     for (i = 0; i < sk_SCT_num(scts); ++i) {
 242         SCT *sct_i = sk_SCT_value(scts, i);
 243         switch (SCT_get_validation_status(sct_i)) {
 244         case SCT_VALIDATION_STATUS_VALID:
 245             ++valid_sct_count;
 246             break;
 247         case SCT_VALIDATION_STATUS_INVALID:
 248             ++invalid_sct_count;
 249             break;
 250         case SCT_VALIDATION_STATUS_NOT_SET:
 251         case SCT_VALIDATION_STATUS_UNKNOWN_LOG:
 252         case SCT_VALIDATION_STATUS_UNVERIFIED:
 253         case SCT_VALIDATION_STATUS_UNKNOWN_VERSION:
 254             /* Ignore other validation statuses. */
 255             break;
 256         }
 257     }
 258
 259     if (valid_sct_count != fixture.expected_valid_sct_count) {
 260         int unverified_sct_count = sk_SCT_num(scts) -
 261                 invalid_sct_count - valid_sct_count;
 262
 263         fprintf(stderr,
 264                 "%d SCTs failed verification\n"
 265                 "%d SCTs passed verification (%d expected)\n"
 266                 "%d SCTs were unverified\n",
 267                 invalid_sct_count,
 268                 valid_sct_count,
 269                 fixture.expected_valid_sct_count,
 270                 unverified_sct_count);
 271         return 0;
 272     }
 273
 274     return 1;
 275 }
 276
 277 static int execute_cert_test(CT_TEST_FIXTURE fixture)
 278 {
 279     int success = 0;
 280     X509 *cert = NULL, *issuer = NULL;
 281     STACK_OF(SCT) *scts = NULL;
 282     SCT *sct = NULL;
 283     char expected_sct_text[CT_TEST_MAX_FILE_SIZE];
 284     int sct_text_len = 0;
 285     unsigned char *tls_sct_list = NULL;
 286     size_t tls_sct_list_len = 0;
 287     CT_POLICY_EVAL_CTX *ct_policy_ctx = CT_POLICY_EVAL_CTX_new();
 288
 289     if (fixture.sct_text_file != NULL) {
 290         sct_text_len = read_text_file(fixture.sct_dir, fixture.sct_text_file,
 291                                       expected_sct_text,
 292                                       CT_TEST_MAX_FILE_SIZE - 1);
 293
 294         if (sct_text_len < 0) {
 295             fprintf(stderr, "Test data file not found: %s\n",
 296                 fixture.sct_text_file);
 297             goto end;
 298         }
 299
 300         expected_sct_text[sct_text_len] = '\0';
 301     }
 302
 303     CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(
 304             ct_policy_ctx, fixture.ctlog_store);
 305
 306     CT_POLICY_EVAL_CTX_set_time(ct_policy_ctx, fixture.epoch_time_in_ms);
 307
 308     if (fixture.certificate_file != NULL) {
 309         int sct_extension_index;
 310         X509_EXTENSION *sct_extension = NULL;
 311         cert = load_pem_cert(fixture.certs_dir, fixture.certificate_file);
 312
 313         if (cert == NULL) {
 314             fprintf(stderr, "Unable to load certificate: %s\n",
 315                 fixture.certificate_file);
 316             goto end;
 317         }
 318
 319         CT_POLICY_EVAL_CTX_set1_cert(ct_policy_ctx, cert);
 320
 321         if (fixture.issuer_file != NULL) {
 322             issuer = load_pem_cert(fixture.certs_dir, fixture.issuer_file);
 323
 324             if (issuer == NULL) {
 325                 fprintf(stderr, "Unable to load issuer certificate: %s\n",
 326                         fixture.issuer_file);
 327                 goto end;
 328             }
 329
 330             CT_POLICY_EVAL_CTX_set1_issuer(ct_policy_ctx, issuer);
 331         }
 332
 333         sct_extension_index =
 334                 X509_get_ext_by_NID(cert, NID_ct_precert_scts, -1);
 335         sct_extension = X509_get_ext(cert, sct_extension_index);
 336         if (fixture.expected_sct_count > 0) {
 337             if (sct_extension == NULL) {
 338                 fprintf(stderr, "SCT extension not found in: %s\n",
 339                     fixture.certificate_file);
 340                 goto end;
 341             }
 342
 343             if (fixture.sct_text_file
 344                 && compare_extension_printout(sct_extension,
 345                                               expected_sct_text)) {
 346                     goto end;
 347             }
 348
 349             if (fixture.test_validity) {
 350                 int i;
 351
 352                 scts = X509V3_EXT_d2i(sct_extension);
 353                 for (i = 0; i < sk_SCT_num(scts); ++i) {
 354                     SCT *sct_i = sk_SCT_value(scts, i);
 355
 356                     if (!SCT_set_source(sct_i, SCT_SOURCE_X509V3_EXTENSION)) {
 357                         fprintf(stderr,
 358                                 "Error setting SCT source to X509v3 extension\n");
 359                         goto end;
 360                     }
 361                 }
 362
 363                 if (!assert_validity(fixture, scts, ct_policy_ctx))
 364                     goto end;
 365             }
 366         } else if (sct_extension != NULL) {
 367             fprintf(stderr,
 368                     "Expected no SCTs, but found SCT extension in: %s\n",
 369                     fixture.certificate_file);
 370             goto end;
 371         }
 372     }
 373
 374     if (fixture.tls_sct_list != NULL) {
 375         const unsigned char *p = fixture.tls_sct_list;
 376         if (o2i_SCT_LIST(&scts, &p, fixture.tls_sct_list_len) == NULL) {
 377             fprintf(stderr, "Failed to decode SCTs from TLS format\n");
 378             goto end;
 379         }
 380
 381         if (fixture.test_validity && cert != NULL) {
 382             if (!assert_validity(fixture, scts, ct_policy_ctx))
 383                 goto end;
 384         }
 385
 386         if (fixture.sct_text_file
 387             && compare_sct_list_printout(scts, expected_sct_text)) {
 388                 goto end;
 389         }
 390
 391         tls_sct_list_len = i2o_SCT_LIST(scts, &tls_sct_list);
 392         if (tls_sct_list_len != fixture.tls_sct_list_len ||
 393             memcmp(fixture.tls_sct_list, tls_sct_list, tls_sct_list_len) != 0) {
 394             fprintf(stderr,
 395                     "Failed to encode SCTs into TLS format correctly\n");
 396             goto end;
 397         }
 398     }
 399     success = 1;
 400
 401 end:
 402     X509_free(cert);
 403     X509_free(issuer);
 404     SCT_LIST_free(scts);
 405     SCT_free(sct);
 406     CT_POLICY_EVAL_CTX_free(ct_policy_ctx);
 407     OPENSSL_free(tls_sct_list);
 408     return success;
 409 }
 410
 411 #define SETUP_CT_TEST_FIXTURE() SETUP_TEST_FIXTURE(CT_TEST_FIXTURE, set_up)
 412 #define EXECUTE_CT_TEST() EXECUTE_TEST(execute_cert_test, tear_down)
 413
 414 static int test_no_scts_in_certificate()
 415 {
 416     SETUP_CT_TEST_FIXTURE();
 417     fixture.certs_dir = certs_dir;
 418     fixture.certificate_file = "leaf.pem";
 419     fixture.issuer_file = "subinterCA.pem";
 420     fixture.expected_sct_count = 0;
 421     EXECUTE_CT_TEST();
 422 }
 423
 424 static int test_one_sct_in_certificate()
 425 {
 426     SETUP_CT_TEST_FIXTURE();
 427     fixture.certs_dir = certs_dir;
 428     fixture.certificate_file = "embeddedSCTs1.pem";
 429     fixture.issuer_file = "embeddedSCTs1_issuer.pem";
 430     fixture.expected_sct_count = 1;
 431     fixture.sct_dir = certs_dir;
 432     fixture.sct_text_file = "embeddedSCTs1.sct";
 433     EXECUTE_CT_TEST();
 434 }
 435
 436 static int test_multiple_scts_in_certificate()
 437 {
 438     SETUP_CT_TEST_FIXTURE();
 439     fixture.certs_dir = certs_dir;
 440     fixture.certificate_file = "embeddedSCTs3.pem";
 441     fixture.issuer_file = "embeddedSCTs3_issuer.pem";
 442     fixture.expected_sct_count = 3;
 443     fixture.sct_dir = certs_dir;
 444     fixture.sct_text_file = "embeddedSCTs3.sct";
 445     EXECUTE_CT_TEST();
 446 }
 447
 448 static int test_verify_one_sct()
 449 {
 450     SETUP_CT_TEST_FIXTURE();
 451     fixture.certs_dir = certs_dir;
 452     fixture.certificate_file = "embeddedSCTs1.pem";
 453     fixture.issuer_file = "embeddedSCTs1_issuer.pem";
 454     fixture.expected_sct_count = fixture.expected_valid_sct_count = 1;
 455     fixture.test_validity = 1;
 456     EXECUTE_CT_TEST();
 457 }
 458
 459 static int test_verify_multiple_scts()
 460 {
 461     SETUP_CT_TEST_FIXTURE();
 462     fixture.certs_dir = certs_dir;
 463     fixture.certificate_file = "embeddedSCTs3.pem";
 464     fixture.issuer_file = "embeddedSCTs3_issuer.pem";
 465     fixture.expected_sct_count = fixture.expected_valid_sct_count = 3;
 466     fixture.test_validity = 1;
 467     EXECUTE_CT_TEST();
 468 }
 469
 470 static int test_verify_fails_for_future_sct()
 471 {
 472     SETUP_CT_TEST_FIXTURE();
 473     fixture.epoch_time_in_ms = 1365094800000; /* Apr 4 17:00:00 2013 GMT */
 474     fixture.certs_dir = certs_dir;
 475     fixture.certificate_file = "embeddedSCTs1.pem";
 476     fixture.issuer_file = "embeddedSCTs1_issuer.pem";
 477     fixture.expected_sct_count = 1;
 478     fixture.expected_valid_sct_count = 0;
 479     fixture.test_validity = 1;
 480     EXECUTE_CT_TEST();
 481 }
 482
 483 static int test_decode_tls_sct()
 484 {
 485     const unsigned char tls_sct_list[] = "\x00\x78" /* length of list */
 486         "\x00\x76"
 487         "\x00" /* version */
 488         /* log ID */
 489         "\xDF\x1C\x2E\xC1\x15\x00\x94\x52\x47\xA9\x61\x68\x32\x5D\xDC\x5C\x79"
 490         "\x59\xE8\xF7\xC6\xD3\x88\xFC\x00\x2E\x0B\xBD\x3F\x74\xD7\x64"
 491         "\x00\x00\x01\x3D\xDB\x27\xDF\x93" /* timestamp */
 492         "\x00\x00" /* extensions length */
 493         "" /* extensions */
 494         "\x04\x03" /* hash and signature algorithms */
 495         "\x00\x47" /* signature length */
 496         /* signature */
 497         "\x30\x45\x02\x20\x48\x2F\x67\x51\xAF\x35\xDB\xA6\x54\x36\xBE\x1F\xD6"
 498         "\x64\x0F\x3D\xBF\x9A\x41\x42\x94\x95\x92\x45\x30\x28\x8F\xA3\xE5\xE2"
 499         "\x3E\x06\x02\x21\x00\xE4\xED\xC0\xDB\x3A\xC5\x72\xB1\xE2\xF5\xE8\xAB"
 500         "\x6A\x68\x06\x53\x98\x7D\xCF\x41\x02\x7D\xFE\xFF\xA1\x05\x51\x9D\x89"
 501         "\xED\xBF\x08";
 502
 503     SETUP_CT_TEST_FIXTURE();
 504     fixture.tls_sct_list = tls_sct_list;
 505     fixture.tls_sct_list_len = 0x7a;
 506     fixture.sct_dir = ct_dir;
 507     fixture.sct_text_file = "tls1.sct";
 508     EXECUTE_CT_TEST();
 509 }
 510
 511 static int test_encode_tls_sct()
 512 {
 513     const char log_id[] = "3xwuwRUAlFJHqWFoMl3cXHlZ6PfG04j8AC4LvT9012Q=";
 514     const uint64_t timestamp = 1;
 515     const char extensions[] = "";
 516     const char signature[] = "BAMARzBAMiBIL2dRrzXbplQ2vh/WZA89v5pBQpSVkkUwKI+j5"
 517             "eI+BgIhAOTtwNs6xXKx4vXoq2poBlOYfc9BAn3+/6EFUZ2J7b8I";
 518     SCT *sct = NULL;
 519
 520     SETUP_CT_TEST_FIXTURE();
 521
 522     fixture.sct_list = sk_SCT_new_null();
 523     sct = SCT_new_from_base64(SCT_VERSION_V1, log_id,
 524                               CT_LOG_ENTRY_TYPE_X509, timestamp,
 525                               extensions, signature);
 526
 527     if (sct == NULL) {
 528         tear_down(fixture);
 529         fprintf(stderr, "Failed to create SCT from base64-encoded test data\n");
 530         return 0;
 531     }
 532
 533     sk_SCT_push(fixture.sct_list, sct);
 534     fixture.sct_dir = ct_dir;
 535     fixture.sct_text_file = "tls1.sct";
 536     EXECUTE_CT_TEST();
 537 }
 538
 539 /*
 540  * Tests that the CT_POLICY_EVAL_CTX default time is approximately now.
 541  * Allow +-10 minutes, as it may compensate for clock skew.
 542  */
 543 static int test_default_ct_policy_eval_ctx_time_is_now()
 544 {
 545     int success = 0;
 546     CT_POLICY_EVAL_CTX *ct_policy_ctx = CT_POLICY_EVAL_CTX_new();
 547     const time_t default_time = CT_POLICY_EVAL_CTX_get_time(ct_policy_ctx) /
 548             1000;
 549     const time_t time_tolerance = 600;  /* 10 minutes */
 550
 551     if (fabs(difftime(time(NULL), default_time)) > time_tolerance) {
 552         fprintf(stderr,
 553                 "Default CT_POLICY_EVAL_CTX time is not approximately now.\n");
 554         goto end;
 555     }
 556
 557     success = 1;
 558 end:
 559     CT_POLICY_EVAL_CTX_free(ct_policy_ctx);
 560     return success;
 561 }
 562
 563 int test_main(int argc, char *argv[])
 564 {
 565     int result = 0;
 566     char *tmp_env;
 567
 568     tmp_env = getenv("CT_DIR");
 569     ct_dir = OPENSSL_strdup(tmp_env != NULL ? tmp_env : "ct");
 570     tmp_env = getenv("CERTS_DIR");
 571     certs_dir = OPENSSL_strdup(tmp_env != NULL ? tmp_env : "certs");
 572
 573     ADD_TEST(test_no_scts_in_certificate);
 574     ADD_TEST(test_one_sct_in_certificate);
 575     ADD_TEST(test_multiple_scts_in_certificate);
 576     ADD_TEST(test_verify_one_sct);
 577     ADD_TEST(test_verify_multiple_scts);
 578     ADD_TEST(test_verify_fails_for_future_sct);
 579     ADD_TEST(test_decode_tls_sct);
 580     ADD_TEST(test_encode_tls_sct);
 581     ADD_TEST(test_default_ct_policy_eval_ctx_time_is_now);
 582
 583     result = run_tests(argv[0]);
 584
 585     OPENSSL_free(ct_dir);
 586     OPENSSL_free(certs_dir);
 587
 588     return result;
 589 }
 590 #else
 591 int test_main(int argc, char *argv[])
 592 {
 593     printf("No CT support\n");
 594     return 0;
 595 }
 596 #endif