1 /*
2  * Copyright 2016-2022 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 <ctype.h>
11 #include <stdio.h>
12 #include <stdlib.h>
13 #include <string.h>
14 
15 #include <openssl/ct.h>
16 #include <openssl/err.h>
17 #include <openssl/pem.h>
18 #include <openssl/x509.h>
19 #include <openssl/x509v3.h>
20 #include "testutil.h"
21 #include <openssl/crypto.h>
22 
23 #ifndef OPENSSL_NO_CT
24 
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 
set_up(const char * const test_case_name)60 static CT_TEST_FIXTURE *set_up(const char *const test_case_name)
61 {
62     CT_TEST_FIXTURE *fixture = NULL;
63 
64     if (!TEST_ptr(fixture = OPENSSL_zalloc(sizeof(*fixture))))
65         goto end;
66     fixture->test_case_name = test_case_name;
67     fixture->epoch_time_in_ms = 1580335307000ULL; /* Wed 29 Jan 2020 10:01:47 PM UTC */
68     if (!TEST_ptr(fixture->ctlog_store = CTLOG_STORE_new())
69             || !TEST_int_eq(
70                     CTLOG_STORE_load_default_file(fixture->ctlog_store), 1))
71         goto end;
72     return fixture;
73 
74 end:
75     if (fixture != NULL)
76         CTLOG_STORE_free(fixture->ctlog_store);
77     OPENSSL_free(fixture);
78     TEST_error("Failed to setup");
79     return NULL;
80 }
81 
tear_down(CT_TEST_FIXTURE * fixture)82 static void tear_down(CT_TEST_FIXTURE *fixture)
83 {
84     if (fixture != NULL) {
85         CTLOG_STORE_free(fixture->ctlog_store);
86         SCT_LIST_free(fixture->sct_list);
87     }
88     OPENSSL_free(fixture);
89 }
90 
load_pem_cert(const char * dir,const char * file)91 static X509 *load_pem_cert(const char *dir, const char *file)
92 {
93     X509 *cert = NULL;
94     char *file_path = test_mk_file_path(dir, file);
95 
96     if (file_path != NULL) {
97         BIO *cert_io = BIO_new_file(file_path, "r");
98 
99         if (cert_io != NULL)
100             cert = PEM_read_bio_X509(cert_io, NULL, NULL, NULL);
101         BIO_free(cert_io);
102     }
103 
104     OPENSSL_free(file_path);
105     return cert;
106 }
107 
read_text_file(const char * dir,const char * file,char * buffer,int buffer_length)108 static int read_text_file(const char *dir, const char *file,
109                           char *buffer, int buffer_length)
110 {
111     int len = -1;
112     char *file_path = test_mk_file_path(dir, file);
113 
114     if (file_path != NULL) {
115         BIO *file_io = BIO_new_file(file_path, "r");
116 
117         if (file_io != NULL)
118             len = BIO_read(file_io, buffer, buffer_length);
119         BIO_free(file_io);
120     }
121 
122     OPENSSL_free(file_path);
123     return len;
124 }
125 
compare_sct_list_printout(STACK_OF (SCT)* sct,const char * expected_output)126 static int compare_sct_list_printout(STACK_OF(SCT) *sct,
127                                      const char *expected_output)
128 {
129     BIO *text_buffer = NULL;
130     char *actual_output = NULL;
131     int result = 0;
132 
133     if (!TEST_ptr(text_buffer = BIO_new(BIO_s_mem())))
134         goto end;
135 
136     SCT_LIST_print(sct, text_buffer, 0, "\n", NULL);
137 
138     /* Append \0 because we're about to use the buffer contents as a string. */
139     if (!TEST_true(BIO_write(text_buffer, "\0", 1)))
140         goto end;
141 
142     BIO_get_mem_data(text_buffer, &actual_output);
143     if (!TEST_str_eq(actual_output, expected_output))
144         goto end;
145     result = 1;
146 
147 end:
148     BIO_free(text_buffer);
149     return result;
150 }
151 
compare_extension_printout(X509_EXTENSION * extension,const char * expected_output)152 static int compare_extension_printout(X509_EXTENSION *extension,
153                                       const char *expected_output)
154 {
155     BIO *text_buffer = NULL;
156     char *actual_output = NULL;
157     int result = 0;
158 
159     if (!TEST_ptr(text_buffer = BIO_new(BIO_s_mem()))
160             || !TEST_true(X509V3_EXT_print(text_buffer, extension,
161                                            X509V3_EXT_DEFAULT, 0)))
162         goto end;
163 
164     /* Append \n because it's easier to create files that end with one. */
165     if (!TEST_true(BIO_write(text_buffer, "\n", 1)))
166         goto end;
167 
168     /* Append \0 because we're about to use the buffer contents as a string. */
169     if (!TEST_true(BIO_write(text_buffer, "\0", 1)))
170         goto end;
171 
172     BIO_get_mem_data(text_buffer, &actual_output);
173     if (!TEST_str_eq(actual_output, expected_output))
174         goto end;
175 
176     result = 1;
177 
178 end:
179     BIO_free(text_buffer);
180     return result;
181 }
182 
assert_validity(CT_TEST_FIXTURE * fixture,STACK_OF (SCT)* scts,CT_POLICY_EVAL_CTX * policy_ctx)183 static int assert_validity(CT_TEST_FIXTURE *fixture, STACK_OF(SCT) *scts,
184                            CT_POLICY_EVAL_CTX *policy_ctx)
185 {
186     int invalid_sct_count = 0;
187     int valid_sct_count = 0;
188     int i;
189 
190     if (!TEST_int_ge(SCT_LIST_validate(scts, policy_ctx), 0))
191         return 0;
192 
193     for (i = 0; i < sk_SCT_num(scts); ++i) {
194         SCT *sct_i = sk_SCT_value(scts, i);
195 
196         switch (SCT_get_validation_status(sct_i)) {
197         case SCT_VALIDATION_STATUS_VALID:
198             ++valid_sct_count;
199             break;
200         case SCT_VALIDATION_STATUS_INVALID:
201             ++invalid_sct_count;
202             break;
203         case SCT_VALIDATION_STATUS_NOT_SET:
204         case SCT_VALIDATION_STATUS_UNKNOWN_LOG:
205         case SCT_VALIDATION_STATUS_UNVERIFIED:
206         case SCT_VALIDATION_STATUS_UNKNOWN_VERSION:
207             /* Ignore other validation statuses. */
208             break;
209         }
210     }
211 
212     if (!TEST_int_eq(valid_sct_count, fixture->expected_valid_sct_count)) {
213         int unverified_sct_count = sk_SCT_num(scts) -
214                                         invalid_sct_count - valid_sct_count;
215 
216         TEST_info("%d SCTs failed, %d SCTs unverified",
217                   invalid_sct_count, unverified_sct_count);
218         return 0;
219     }
220 
221     return 1;
222 }
223 
execute_cert_test(CT_TEST_FIXTURE * fixture)224 static int execute_cert_test(CT_TEST_FIXTURE *fixture)
225 {
226     int success = 0;
227     X509 *cert = NULL, *issuer = NULL;
228     STACK_OF(SCT) *scts = NULL;
229     SCT *sct = NULL;
230     char expected_sct_text[CT_TEST_MAX_FILE_SIZE];
231     int sct_text_len = 0;
232     unsigned char *tls_sct_list = NULL;
233     size_t tls_sct_list_len = 0;
234     CT_POLICY_EVAL_CTX *ct_policy_ctx = CT_POLICY_EVAL_CTX_new();
235 
236     if (fixture->sct_text_file != NULL) {
237         sct_text_len = read_text_file(fixture->sct_dir, fixture->sct_text_file,
238                                       expected_sct_text,
239                                       CT_TEST_MAX_FILE_SIZE - 1);
240 
241         if (!TEST_int_ge(sct_text_len, 0))
242             goto end;
243         expected_sct_text[sct_text_len] = '\0';
244     }
245 
246     CT_POLICY_EVAL_CTX_set_shared_CTLOG_STORE(
247             ct_policy_ctx, fixture->ctlog_store);
248 
249     CT_POLICY_EVAL_CTX_set_time(ct_policy_ctx, fixture->epoch_time_in_ms);
250 
251     if (fixture->certificate_file != NULL) {
252         int sct_extension_index;
253         int i;
254         X509_EXTENSION *sct_extension = NULL;
255 
256         if (!TEST_ptr(cert = load_pem_cert(fixture->certs_dir,
257                                            fixture->certificate_file)))
258             goto end;
259 
260         CT_POLICY_EVAL_CTX_set1_cert(ct_policy_ctx, cert);
261 
262         if (fixture->issuer_file != NULL) {
263             if (!TEST_ptr(issuer = load_pem_cert(fixture->certs_dir,
264                                                  fixture->issuer_file)))
265                 goto end;
266             CT_POLICY_EVAL_CTX_set1_issuer(ct_policy_ctx, issuer);
267         }
268 
269         sct_extension_index =
270                 X509_get_ext_by_NID(cert, NID_ct_precert_scts, -1);
271         sct_extension = X509_get_ext(cert, sct_extension_index);
272         if (fixture->expected_sct_count > 0) {
273             if (!TEST_ptr(sct_extension))
274                 goto end;
275 
276             if (fixture->sct_text_file
277                 && !compare_extension_printout(sct_extension,
278                                                expected_sct_text))
279                     goto end;
280 
281             scts = X509V3_EXT_d2i(sct_extension);
282             for (i = 0; i < sk_SCT_num(scts); ++i) {
283                 SCT *sct_i = sk_SCT_value(scts, i);
284 
285                 if (!TEST_int_eq(SCT_get_source(sct_i),
286                                  SCT_SOURCE_X509V3_EXTENSION)) {
287                     goto end;
288                 }
289             }
290 
291             if (fixture->test_validity) {
292                 if (!assert_validity(fixture, scts, ct_policy_ctx))
293                     goto end;
294             }
295         } else if (!TEST_ptr_null(sct_extension)) {
296             goto end;
297         }
298     }
299 
300     if (fixture->tls_sct_list != NULL) {
301         const unsigned char *p = fixture->tls_sct_list;
302 
303         if (!TEST_ptr(o2i_SCT_LIST(&scts, &p, fixture->tls_sct_list_len)))
304             goto end;
305 
306         if (fixture->test_validity && cert != NULL) {
307             if (!assert_validity(fixture, scts, ct_policy_ctx))
308                 goto end;
309         }
310 
311         if (fixture->sct_text_file
312             && !compare_sct_list_printout(scts, expected_sct_text)) {
313                 goto end;
314         }
315 
316         tls_sct_list_len = i2o_SCT_LIST(scts, &tls_sct_list);
317         if (!TEST_mem_eq(fixture->tls_sct_list, fixture->tls_sct_list_len,
318                          tls_sct_list, tls_sct_list_len))
319             goto end;
320     }
321     success = 1;
322 
323 end:
324     X509_free(cert);
325     X509_free(issuer);
326     SCT_LIST_free(scts);
327     SCT_free(sct);
328     CT_POLICY_EVAL_CTX_free(ct_policy_ctx);
329     OPENSSL_free(tls_sct_list);
330     return success;
331 }
332 
333 # define SETUP_CT_TEST_FIXTURE() SETUP_TEST_FIXTURE(CT_TEST_FIXTURE, set_up)
334 # define EXECUTE_CT_TEST() EXECUTE_TEST(execute_cert_test, tear_down)
335 
test_no_scts_in_certificate(void)336 static int test_no_scts_in_certificate(void)
337 {
338     SETUP_CT_TEST_FIXTURE();
339     fixture->certs_dir = certs_dir;
340     fixture->certificate_file = "leaf.pem";
341     fixture->issuer_file = "subinterCA.pem";
342     fixture->expected_sct_count = 0;
343     EXECUTE_CT_TEST();
344     return result;
345 }
346 
test_one_sct_in_certificate(void)347 static int test_one_sct_in_certificate(void)
348 {
349     SETUP_CT_TEST_FIXTURE();
350     fixture->certs_dir = certs_dir;
351     fixture->certificate_file = "embeddedSCTs1.pem";
352     fixture->issuer_file = "embeddedSCTs1_issuer.pem";
353     fixture->expected_sct_count = 1;
354     fixture->sct_dir = certs_dir;
355     fixture->sct_text_file = "embeddedSCTs1.sct";
356     EXECUTE_CT_TEST();
357     return result;
358 }
359 
test_multiple_scts_in_certificate(void)360 static int test_multiple_scts_in_certificate(void)
361 {
362     SETUP_CT_TEST_FIXTURE();
363     fixture->certs_dir = certs_dir;
364     fixture->certificate_file = "embeddedSCTs3.pem";
365     fixture->issuer_file = "embeddedSCTs3_issuer.pem";
366     fixture->expected_sct_count = 3;
367     fixture->sct_dir = certs_dir;
368     fixture->sct_text_file = "embeddedSCTs3.sct";
369     EXECUTE_CT_TEST();
370     return result;
371 }
372 
test_verify_one_sct(void)373 static int test_verify_one_sct(void)
374 {
375     SETUP_CT_TEST_FIXTURE();
376     fixture->certs_dir = certs_dir;
377     fixture->certificate_file = "embeddedSCTs1.pem";
378     fixture->issuer_file = "embeddedSCTs1_issuer.pem";
379     fixture->expected_sct_count = fixture->expected_valid_sct_count = 1;
380     fixture->test_validity = 1;
381     EXECUTE_CT_TEST();
382     return result;
383 }
384 
test_verify_multiple_scts(void)385 static int test_verify_multiple_scts(void)
386 {
387     SETUP_CT_TEST_FIXTURE();
388     fixture->certs_dir = certs_dir;
389     fixture->certificate_file = "embeddedSCTs3.pem";
390     fixture->issuer_file = "embeddedSCTs3_issuer.pem";
391     fixture->expected_sct_count = fixture->expected_valid_sct_count = 3;
392     fixture->test_validity = 1;
393     EXECUTE_CT_TEST();
394     return result;
395 }
396 
test_verify_fails_for_future_sct(void)397 static int test_verify_fails_for_future_sct(void)
398 {
399     SETUP_CT_TEST_FIXTURE();
400     fixture->epoch_time_in_ms = 1365094800000ULL; /* Apr 4 17:00:00 2013 GMT */
401     fixture->certs_dir = certs_dir;
402     fixture->certificate_file = "embeddedSCTs1.pem";
403     fixture->issuer_file = "embeddedSCTs1_issuer.pem";
404     fixture->expected_sct_count = 1;
405     fixture->expected_valid_sct_count = 0;
406     fixture->test_validity = 1;
407     EXECUTE_CT_TEST();
408     return result;
409 }
410 
test_decode_tls_sct(void)411 static int test_decode_tls_sct(void)
412 {
413     const unsigned char tls_sct_list[] = "\x00\x78" /* length of list */
414         "\x00\x76"
415         "\x00" /* version */
416         /* log ID */
417         "\xDF\x1C\x2E\xC1\x15\x00\x94\x52\x47\xA9\x61\x68\x32\x5D\xDC\x5C\x79"
418         "\x59\xE8\xF7\xC6\xD3\x88\xFC\x00\x2E\x0B\xBD\x3F\x74\xD7\x64"
419         "\x00\x00\x01\x3D\xDB\x27\xDF\x93" /* timestamp */
420         "\x00\x00" /* extensions length */
421         "" /* extensions */
422         "\x04\x03" /* hash and signature algorithms */
423         "\x00\x47" /* signature length */
424         /* signature */
425         "\x30\x45\x02\x20\x48\x2F\x67\x51\xAF\x35\xDB\xA6\x54\x36\xBE\x1F\xD6"
426         "\x64\x0F\x3D\xBF\x9A\x41\x42\x94\x95\x92\x45\x30\x28\x8F\xA3\xE5\xE2"
427         "\x3E\x06\x02\x21\x00\xE4\xED\xC0\xDB\x3A\xC5\x72\xB1\xE2\xF5\xE8\xAB"
428         "\x6A\x68\x06\x53\x98\x7D\xCF\x41\x02\x7D\xFE\xFF\xA1\x05\x51\x9D\x89"
429         "\xED\xBF\x08";
430 
431     SETUP_CT_TEST_FIXTURE();
432     fixture->tls_sct_list = tls_sct_list;
433     fixture->tls_sct_list_len = 0x7a;
434     fixture->sct_dir = ct_dir;
435     fixture->sct_text_file = "tls1.sct";
436     EXECUTE_CT_TEST();
437     return result;
438 }
439 
test_encode_tls_sct(void)440 static int test_encode_tls_sct(void)
441 {
442     const char log_id[] = "3xwuwRUAlFJHqWFoMl3cXHlZ6PfG04j8AC4LvT9012Q=";
443     const uint64_t timestamp = 1;
444     const char extensions[] = "";
445     const char signature[] = "BAMARzBAMiBIL2dRrzXbplQ2vh/WZA89v5pBQpSVkkUwKI+j5"
446             "eI+BgIhAOTtwNs6xXKx4vXoq2poBlOYfc9BAn3+/6EFUZ2J7b8I";
447     SCT *sct = NULL;
448 
449     SETUP_CT_TEST_FIXTURE();
450 
451     fixture->sct_list = sk_SCT_new_null();
452     if (fixture->sct_list == NULL)
453 	    return 0;
454 
455     if (!TEST_ptr(sct = SCT_new_from_base64(SCT_VERSION_V1, log_id,
456                                             CT_LOG_ENTRY_TYPE_X509, timestamp,
457                                             extensions, signature)))
458 
459         return 0;
460 
461     sk_SCT_push(fixture->sct_list, sct);
462     fixture->sct_dir = ct_dir;
463     fixture->sct_text_file = "tls1.sct";
464     EXECUTE_CT_TEST();
465     return result;
466 }
467 
468 /*
469  * Tests that the CT_POLICY_EVAL_CTX default time is approximately now.
470  * Allow +-10 minutes, as it may compensate for clock skew.
471  */
test_default_ct_policy_eval_ctx_time_is_now(void)472 static int test_default_ct_policy_eval_ctx_time_is_now(void)
473 {
474     int success = 0;
475     CT_POLICY_EVAL_CTX *ct_policy_ctx = CT_POLICY_EVAL_CTX_new();
476     const time_t default_time =
477         (time_t)(CT_POLICY_EVAL_CTX_get_time(ct_policy_ctx) / 1000);
478     const time_t time_tolerance = 600;  /* 10 minutes */
479 
480     if (!TEST_time_t_le(abs((int)difftime(time(NULL), default_time)),
481                         time_tolerance))
482         goto end;
483 
484     success = 1;
485 end:
486     CT_POLICY_EVAL_CTX_free(ct_policy_ctx);
487     return success;
488 }
489 
test_ctlog_from_base64(void)490 static int test_ctlog_from_base64(void)
491 {
492     CTLOG *ctlogp = NULL;
493     const char notb64[] = "\01\02\03\04";
494     const char pad[] = "====";
495     const char name[] = "name";
496 
497     /* We expect these to both fail! */
498     if (!TEST_true(!CTLOG_new_from_base64(&ctlogp, notb64, name))
499         || !TEST_true(!CTLOG_new_from_base64(&ctlogp, pad, name)))
500         return 0;
501     return 1;
502 }
503 #endif
504 
setup_tests(void)505 int setup_tests(void)
506 {
507 #ifndef OPENSSL_NO_CT
508     if ((ct_dir = getenv("CT_DIR")) == NULL)
509         ct_dir = "ct";
510     if ((certs_dir = getenv("CERTS_DIR")) == NULL)
511         certs_dir = "certs";
512 
513     ADD_TEST(test_no_scts_in_certificate);
514     ADD_TEST(test_one_sct_in_certificate);
515     ADD_TEST(test_multiple_scts_in_certificate);
516     ADD_TEST(test_verify_one_sct);
517     ADD_TEST(test_verify_multiple_scts);
518     ADD_TEST(test_verify_fails_for_future_sct);
519     ADD_TEST(test_decode_tls_sct);
520     ADD_TEST(test_encode_tls_sct);
521     ADD_TEST(test_default_ct_policy_eval_ctx_time_is_now);
522     ADD_TEST(test_ctlog_from_base64);
523 #else
524     printf("No CT support\n");
525 #endif
526     return 1;
527 }
528