1 /*
2 * Copyright 2015-2022 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 <stdio.h>
11 #include <openssl/crypto.h>
12 #include <openssl/bio.h>
13 #include <openssl/x509.h>
14 #include <openssl/x509v3.h>
15 #include <openssl/pem.h>
16 #include <openssl/err.h>
17 #include "testutil.h"
18
19 static const char *certs_dir;
20 static char *roots_f = NULL;
21 static char *untrusted_f = NULL;
22 static char *bad_f = NULL;
23 static char *good_f = NULL;
24 static char *sroot_cert = NULL;
25 static char *ca_cert = NULL;
26 static char *ee_cert = NULL;
27
load_cert_pem(const char * file)28 static X509 *load_cert_pem(const char *file)
29 {
30 X509 *cert = NULL;
31 BIO *bio = NULL;
32
33 if (!TEST_ptr(bio = BIO_new(BIO_s_file())))
34 return NULL;
35 if (TEST_int_gt(BIO_read_filename(bio, file), 0))
36 (void)TEST_ptr(cert = PEM_read_bio_X509(bio, NULL, NULL, NULL));
37
38 BIO_free(bio);
39 return cert;
40 }
41
STACK_OF(X509)42 static STACK_OF(X509) *load_certs_from_file(const char *filename)
43 {
44 STACK_OF(X509) *certs;
45 BIO *bio;
46 X509 *x;
47
48 bio = BIO_new_file(filename, "r");
49
50 if (bio == NULL) {
51 return NULL;
52 }
53
54 certs = sk_X509_new_null();
55 if (certs == NULL) {
56 BIO_free(bio);
57 return NULL;
58 }
59
60 ERR_set_mark();
61 do {
62 x = PEM_read_bio_X509(bio, NULL, 0, NULL);
63 if (x != NULL && !sk_X509_push(certs, x)) {
64 sk_X509_pop_free(certs, X509_free);
65 BIO_free(bio);
66 return NULL;
67 } else if (x == NULL) {
68 /*
69 * We probably just ran out of certs, so ignore any errors
70 * generated
71 */
72 ERR_pop_to_mark();
73 }
74 } while (x != NULL);
75
76 BIO_free(bio);
77
78 return certs;
79 }
80
81 /*-
82 * Test for CVE-2015-1793 (Alternate Chains Certificate Forgery)
83 *
84 * Chain is as follows:
85 *
86 * rootCA (self-signed)
87 * |
88 * interCA
89 * |
90 * subinterCA subinterCA (self-signed)
91 * | |
92 * leaf ------------------
93 * |
94 * bad
95 *
96 * rootCA, interCA, subinterCA, subinterCA (ss) all have CA=TRUE
97 * leaf and bad have CA=FALSE
98 *
99 * subinterCA and subinterCA (ss) have the same subject name and keys
100 *
101 * interCA (but not rootCA) and subinterCA (ss) are in the trusted store
102 * (roots.pem)
103 * leaf and subinterCA are in the untrusted list (untrusted.pem)
104 * bad is the certificate being verified (bad.pem)
105 *
106 * Versions vulnerable to CVE-2015-1793 will fail to detect that leaf has
107 * CA=FALSE, and will therefore incorrectly verify bad
108 *
109 */
test_alt_chains_cert_forgery(void)110 static int test_alt_chains_cert_forgery(void)
111 {
112 int ret = 0;
113 int i;
114 X509 *x = NULL;
115 STACK_OF(X509) *untrusted = NULL;
116 BIO *bio = NULL;
117 X509_STORE_CTX *sctx = NULL;
118 X509_STORE *store = NULL;
119 X509_LOOKUP *lookup = NULL;
120
121 store = X509_STORE_new();
122 if (store == NULL)
123 goto err;
124
125 lookup = X509_STORE_add_lookup(store, X509_LOOKUP_file());
126 if (lookup == NULL)
127 goto err;
128 if (!X509_LOOKUP_load_file(lookup, roots_f, X509_FILETYPE_PEM))
129 goto err;
130
131 untrusted = load_certs_from_file(untrusted_f);
132
133 if ((bio = BIO_new_file(bad_f, "r")) == NULL)
134 goto err;
135
136 if ((x = PEM_read_bio_X509(bio, NULL, 0, NULL)) == NULL)
137 goto err;
138
139 sctx = X509_STORE_CTX_new();
140 if (sctx == NULL)
141 goto err;
142
143 if (!X509_STORE_CTX_init(sctx, store, x, untrusted))
144 goto err;
145
146 i = X509_verify_cert(sctx);
147
148 if (i != 0 || X509_STORE_CTX_get_error(sctx) != X509_V_ERR_INVALID_CA)
149 goto err;
150
151 /* repeat with X509_V_FLAG_X509_STRICT */
152 X509_STORE_CTX_cleanup(sctx);
153 X509_STORE_set_flags(store, X509_V_FLAG_X509_STRICT);
154
155 if (!X509_STORE_CTX_init(sctx, store, x, untrusted))
156 goto err;
157
158 i = X509_verify_cert(sctx);
159
160 if (i == 0 && X509_STORE_CTX_get_error(sctx) == X509_V_ERR_INVALID_CA)
161 /* This is the result we were expecting: Test passed */
162 ret = 1;
163
164 err:
165 X509_STORE_CTX_free(sctx);
166 X509_free(x);
167 BIO_free(bio);
168 sk_X509_pop_free(untrusted, X509_free);
169 X509_STORE_free(store);
170 return ret;
171 }
172
test_store_ctx(void)173 static int test_store_ctx(void)
174 {
175 X509_STORE_CTX *sctx = NULL;
176 X509 *x = NULL;
177 BIO *bio = NULL;
178 int testresult = 0, ret;
179
180 bio = BIO_new_file(bad_f, "r");
181 if (bio == NULL)
182 goto err;
183
184 x = PEM_read_bio_X509(bio, NULL, 0, NULL);
185 if (x == NULL)
186 goto err;
187
188 sctx = X509_STORE_CTX_new();
189 if (sctx == NULL)
190 goto err;
191
192 if (!X509_STORE_CTX_init(sctx, NULL, x, NULL))
193 goto err;
194
195 /* Verifying a cert where we have no trusted certs should fail */
196 ret = X509_verify_cert(sctx);
197
198 if (ret == 0) {
199 /* This is the result we were expecting: Test passed */
200 testresult = 1;
201 }
202
203 err:
204 X509_STORE_CTX_free(sctx);
205 X509_free(x);
206 BIO_free(bio);
207 return testresult;
208 }
209
test_self_signed(const char * filename,int expected)210 static int test_self_signed(const char *filename, int expected)
211 {
212 X509 *cert = load_cert_pem(filename);
213 STACK_OF(X509) *trusted = sk_X509_new_null();
214 X509_STORE_CTX *ctx = X509_STORE_CTX_new();
215 int ret;
216
217 ret = TEST_ptr(cert)
218 && TEST_true(sk_X509_push(trusted, cert))
219 && TEST_true(X509_STORE_CTX_init(ctx, NULL, cert, NULL));
220 X509_STORE_CTX_set0_trusted_stack(ctx, trusted);
221 ret = ret && TEST_int_eq(X509_verify_cert(ctx), expected);
222
223 X509_STORE_CTX_free(ctx);
224 sk_X509_free(trusted);
225 X509_free(cert);
226 return ret;
227 }
228
test_self_signed_good(void)229 static int test_self_signed_good(void)
230 {
231 return test_self_signed(good_f, 1);
232 }
233
test_self_signed_bad(void)234 static int test_self_signed_bad(void)
235 {
236 return test_self_signed(bad_f, 0);
237 }
238
do_test_purpose(int purpose,int expected)239 static int do_test_purpose(int purpose, int expected)
240 {
241 X509 *eecert = load_cert_pem(ee_cert); /* may result in NULL */
242 X509 *untrcert = load_cert_pem(ca_cert);
243 X509 *trcert = load_cert_pem(sroot_cert);
244 STACK_OF(X509) *trusted = sk_X509_new_null();
245 STACK_OF(X509) *untrusted = sk_X509_new_null();
246 X509_STORE_CTX *ctx = X509_STORE_CTX_new();
247 int testresult = 0;
248
249 if (!TEST_ptr(eecert)
250 || !TEST_ptr(untrcert)
251 || !TEST_ptr(trcert)
252 || !TEST_ptr(trusted)
253 || !TEST_ptr(untrusted)
254 || !TEST_ptr(ctx))
255 goto err;
256
257
258 if (!TEST_true(sk_X509_push(trusted, trcert)))
259 goto err;
260 trcert = NULL;
261 if (!TEST_true(sk_X509_push(untrusted, untrcert)))
262 goto err;
263 untrcert = NULL;
264
265 if (!TEST_true(X509_STORE_CTX_init(ctx, NULL, eecert, untrusted)))
266 goto err;
267
268 if (!TEST_true(X509_STORE_CTX_set_purpose(ctx, purpose)))
269 goto err;
270
271 /*
272 * X509_STORE_CTX_set0_trusted_stack() is bady named. Despite the set0 name
273 * we are still responsible for freeing trusted after we have finished with
274 * it.
275 */
276 X509_STORE_CTX_set0_trusted_stack(ctx, trusted);
277
278 if (!TEST_int_eq(X509_verify_cert(ctx), expected))
279 goto err;
280
281 testresult = 1;
282 err:
283 sk_X509_pop_free(trusted, X509_free);
284 sk_X509_pop_free(untrusted, X509_free);
285 X509_STORE_CTX_free(ctx);
286 X509_free(eecert);
287 X509_free(untrcert);
288 X509_free(trcert);
289 return testresult;
290 }
291
test_purpose_ssl_client(void)292 static int test_purpose_ssl_client(void)
293 {
294 return do_test_purpose(X509_PURPOSE_SSL_CLIENT, 0);
295 }
296
test_purpose_ssl_server(void)297 static int test_purpose_ssl_server(void)
298 {
299 return do_test_purpose(X509_PURPOSE_SSL_SERVER, 1);
300 }
301
test_purpose_any(void)302 static int test_purpose_any(void)
303 {
304 return do_test_purpose(X509_PURPOSE_ANY, 1);
305 }
306
setup_tests(void)307 int setup_tests(void)
308 {
309 if (!TEST_ptr(certs_dir = test_get_argument(0))) {
310 TEST_error("usage: verify_extra_test certs-dir\n");
311 return 0;
312 }
313
314 if (!TEST_ptr(roots_f = test_mk_file_path(certs_dir, "roots.pem"))
315 || !TEST_ptr(untrusted_f = test_mk_file_path(certs_dir, "untrusted.pem"))
316 || !TEST_ptr(bad_f = test_mk_file_path(certs_dir, "bad.pem"))
317 || !TEST_ptr(good_f = test_mk_file_path(certs_dir, "rootCA.pem"))
318 || !TEST_ptr(sroot_cert = test_mk_file_path(certs_dir, "sroot-cert.pem"))
319 || !TEST_ptr(ca_cert = test_mk_file_path(certs_dir, "ca-cert.pem"))
320 || !TEST_ptr(ee_cert = test_mk_file_path(certs_dir, "ee-cert.pem")))
321 goto err;
322
323 ADD_TEST(test_alt_chains_cert_forgery);
324 ADD_TEST(test_store_ctx);
325 ADD_TEST(test_self_signed_good);
326 ADD_TEST(test_self_signed_bad);
327 ADD_TEST(test_purpose_ssl_client);
328 ADD_TEST(test_purpose_ssl_server);
329 ADD_TEST(test_purpose_any);
330 return 1;
331 err:
332 cleanup_tests();
333 return 0;
334 }
335
cleanup_tests(void)336 void cleanup_tests(void)
337 {
338 OPENSSL_free(roots_f);
339 OPENSSL_free(untrusted_f);
340 OPENSSL_free(bad_f);
341 OPENSSL_free(good_f);
342 OPENSSL_free(sroot_cert);
343 OPENSSL_free(ca_cert);
344 OPENSSL_free(ee_cert);
345 }
346