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 <string.h>
11 #include "helpers/ssltestlib.h"
12 #include "testutil.h"
13 
14 static int docorrupt = 0;
15 
16 static void copy_flags(BIO *bio)
17 {
18     int flags;
19     BIO *next = BIO_next(bio);
20 
21     flags = BIO_test_flags(next, BIO_FLAGS_SHOULD_RETRY | BIO_FLAGS_RWS);
22     BIO_clear_flags(bio, BIO_FLAGS_SHOULD_RETRY | BIO_FLAGS_RWS);
23     BIO_set_flags(bio, flags);
24 }
25 
26 static int tls_corrupt_read(BIO *bio, char *out, int outl)
27 {
28     int ret;
29     BIO *next = BIO_next(bio);
30 
31     ret = BIO_read(next, out, outl);
32     copy_flags(bio);
33 
34     return ret;
35 }
36 
37 static int tls_corrupt_write(BIO *bio, const char *in, int inl)
38 {
39     int ret;
40     BIO *next = BIO_next(bio);
41     char *copy;
42 
43     if (docorrupt) {
44         if (!TEST_ptr(copy = OPENSSL_memdup(in, inl)))
45             return 0;
46         /* corrupt last bit of application data */
47         copy[inl-1] ^= 1;
48         ret = BIO_write(next, copy, inl);
49         OPENSSL_free(copy);
50     } else {
51         ret = BIO_write(next, in, inl);
52     }
53     copy_flags(bio);
54 
55     return ret;
56 }
57 
58 static long tls_corrupt_ctrl(BIO *bio, int cmd, long num, void *ptr)
59 {
60     long ret;
61     BIO *next = BIO_next(bio);
62 
63     if (next == NULL)
64         return 0;
65 
66     switch (cmd) {
67     case BIO_CTRL_DUP:
68         ret = 0L;
69         break;
70     default:
71         ret = BIO_ctrl(next, cmd, num, ptr);
72         break;
73     }
74     return ret;
75 }
76 
77 static int tls_corrupt_gets(BIO *bio, char *buf, int size)
78 {
79     /* We don't support this - not needed anyway */
80     return -1;
81 }
82 
83 static int tls_corrupt_puts(BIO *bio, const char *str)
84 {
85     /* We don't support this - not needed anyway */
86     return -1;
87 }
88 
89 static int tls_corrupt_new(BIO *bio)
90 {
91     BIO_set_init(bio, 1);
92 
93     return 1;
94 }
95 
96 static int tls_corrupt_free(BIO *bio)
97 {
98     BIO_set_init(bio, 0);
99 
100     return 1;
101 }
102 
103 #define BIO_TYPE_CUSTOM_FILTER  (0x80 | BIO_TYPE_FILTER)
104 
105 static BIO_METHOD *method_tls_corrupt = NULL;
106 
107 /* Note: Not thread safe! */
108 static const BIO_METHOD *bio_f_tls_corrupt_filter(void)
109 {
110     if (method_tls_corrupt == NULL) {
111         method_tls_corrupt = BIO_meth_new(BIO_TYPE_CUSTOM_FILTER,
112                                           "TLS corrupt filter");
113         if (   method_tls_corrupt == NULL
114             || !BIO_meth_set_write(method_tls_corrupt, tls_corrupt_write)
115             || !BIO_meth_set_read(method_tls_corrupt, tls_corrupt_read)
116             || !BIO_meth_set_puts(method_tls_corrupt, tls_corrupt_puts)
117             || !BIO_meth_set_gets(method_tls_corrupt, tls_corrupt_gets)
118             || !BIO_meth_set_ctrl(method_tls_corrupt, tls_corrupt_ctrl)
119             || !BIO_meth_set_create(method_tls_corrupt, tls_corrupt_new)
120             || !BIO_meth_set_destroy(method_tls_corrupt, tls_corrupt_free))
121             return NULL;
122     }
123     return method_tls_corrupt;
124 }
125 
126 static void bio_f_tls_corrupt_filter_free(void)
127 {
128     BIO_meth_free(method_tls_corrupt);
129 }
130 
131 /*
132  * The test is supposed to be executed with RSA key, customarily
133  * with apps/server.pem used even in other tests. For this reason
134  * |cipher_list| is initialized with RSA ciphers' names. This
135  * naturally means that if test is to be re-purposed for other
136  * type of key, then NID_auth_* filter below would need adjustment.
137  */
138 static const char **cipher_list = NULL;
139 
140 static int setup_cipher_list(void)
141 {
142     SSL_CTX *ctx = NULL;
143     SSL *ssl = NULL;
144     STACK_OF(SSL_CIPHER) *sk_ciphers = NULL;
145     int i, j, numciphers = 0;
146 
147     if (!TEST_ptr(ctx = SSL_CTX_new(TLS_server_method()))
148             || !TEST_ptr(ssl = SSL_new(ctx))
149             || !TEST_ptr(sk_ciphers = SSL_get1_supported_ciphers(ssl)))
150         goto err;
151 
152     /*
153      * The |cipher_list| will be filled only with names of RSA ciphers,
154      * so that some of the allocated space will be wasted, but the loss
155      * is deemed acceptable...
156      */
157     cipher_list = OPENSSL_malloc(sk_SSL_CIPHER_num(sk_ciphers) *
158                                  sizeof(cipher_list[0]));
159     if (!TEST_ptr(cipher_list))
160         goto err;
161 
162     for (j = 0, i = 0; i < sk_SSL_CIPHER_num(sk_ciphers); i++) {
163         const SSL_CIPHER *cipher = sk_SSL_CIPHER_value(sk_ciphers, i);
164 
165         if (SSL_CIPHER_get_auth_nid(cipher) == NID_auth_rsa)
166             cipher_list[j++] = SSL_CIPHER_get_name(cipher);
167     }
168     if (TEST_int_ne(j, 0))
169         numciphers = j;
170 
171 err:
172     sk_SSL_CIPHER_free(sk_ciphers);
173     SSL_free(ssl);
174     SSL_CTX_free(ctx);
175 
176     return numciphers;
177 }
178 
179 static char *cert = NULL;
180 static char *privkey = NULL;
181 
182 static int test_ssl_corrupt(int testidx)
183 {
184     static unsigned char junk[16000] = { 0 };
185     SSL_CTX *sctx = NULL, *cctx = NULL;
186     SSL *server = NULL, *client = NULL;
187     BIO *c_to_s_fbio;
188     int testresult = 0;
189     STACK_OF(SSL_CIPHER) *ciphers;
190     const SSL_CIPHER *currcipher;
191     int err;
192 
193     docorrupt = 0;
194 
195     TEST_info("Starting #%d, %s", testidx, cipher_list[testidx]);
196 
197     if (!TEST_true(create_ssl_ctx_pair(NULL, TLS_server_method(),
198                                        TLS_client_method(),
199                                        TLS1_VERSION, 0,
200                                        &sctx, &cctx, cert, privkey)))
201         return 0;
202 
203     if (!TEST_true(SSL_CTX_set_dh_auto(sctx, 1))
204             || !TEST_true(SSL_CTX_set_cipher_list(cctx, cipher_list[testidx]))
205             || !TEST_true(SSL_CTX_set_ciphersuites(cctx, ""))
206             || !TEST_ptr(ciphers = SSL_CTX_get_ciphers(cctx))
207             || !TEST_int_eq(sk_SSL_CIPHER_num(ciphers), 1)
208             || !TEST_ptr(currcipher = sk_SSL_CIPHER_value(ciphers, 0)))
209         goto end;
210 
211     /*
212      * No ciphers we are using are TLSv1.3 compatible so we should not attempt
213      * to negotiate TLSv1.3
214      */
215     if (!TEST_true(SSL_CTX_set_max_proto_version(cctx, TLS1_2_VERSION)))
216         goto end;
217 
218     if (!TEST_ptr(c_to_s_fbio = BIO_new(bio_f_tls_corrupt_filter())))
219         goto end;
220 
221     /* BIO is freed by create_ssl_connection on error */
222     if (!TEST_true(create_ssl_objects(sctx, cctx, &server, &client, NULL,
223                                       c_to_s_fbio)))
224         goto end;
225 
226     if (!TEST_true(create_ssl_connection(server, client, SSL_ERROR_NONE)))
227         goto end;
228 
229     docorrupt = 1;
230 
231     if (!TEST_int_ge(SSL_write(client, junk, sizeof(junk)), 0))
232         goto end;
233 
234     if (!TEST_int_lt(SSL_read(server, junk, sizeof(junk)), 0))
235         goto end;
236 
237     do {
238         err = ERR_get_error();
239 
240         if (err == 0) {
241             TEST_error("Decryption failed or bad record MAC not seen");
242             goto end;
243         }
244     } while (ERR_GET_REASON(err) != SSL_R_DECRYPTION_FAILED_OR_BAD_RECORD_MAC);
245 
246     testresult = 1;
247  end:
248     SSL_free(server);
249     SSL_free(client);
250     SSL_CTX_free(sctx);
251     SSL_CTX_free(cctx);
252     return testresult;
253 }
254 
255 OPT_TEST_DECLARE_USAGE("certfile privkeyfile\n")
256 
257 int setup_tests(void)
258 {
259     int n;
260 
261     if (!test_skip_common_options()) {
262         TEST_error("Error parsing test options\n");
263         return 0;
264     }
265 
266     if (!TEST_ptr(cert = test_get_argument(0))
267             || !TEST_ptr(privkey = test_get_argument(1)))
268         return 0;
269 
270     n = setup_cipher_list();
271     if (n > 0)
272         ADD_ALL_TESTS(test_ssl_corrupt, n);
273     return 1;
274 }
275 
276 void cleanup_tests(void)
277 {
278     bio_f_tls_corrupt_filter_free();
279     OPENSSL_free(cipher_list);
280 }
281