1 /*
2 * Simple DTLS server program that does the same thing as echo-server but
3 * over encrypted UDP link.
4 *
5 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
6 * Copyright (C) 2017 Intel Corporation
7 * SPDX-License-Identifier: Apache-2.0
8 *
9 * Licensed under the Apache License, Version 2.0 (the "License"); you may
10 * not use this file except in compliance with the License.
11 * You may obtain a copy of the License at
12 *
13 * http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
17 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 *
21 */
22
23 #include <stdbool.h>
24 #include <unistd.h>
25 #include <errno.h>
26
27 #if !defined(MBEDTLS_CONFIG_FILE)
28 #include "mbedtls/config.h"
29 #else
30 #include MBEDTLS_CONFIG_FILE
31 #endif
32
33 #if defined(MBEDTLS_PLATFORM_C)
34 #include "mbedtls/platform.h"
35 #else
36 #include <stdio.h>
37 #define mbedtls_printf printf
38 #define mbedtls_fprintf fprintf
39 #define mbedtls_time_t time_t
40 #endif
41
42 #if !defined(MBEDTLS_SSL_SRV_C) || !defined(MBEDTLS_SSL_PROTO_DTLS) || \
43 !defined(MBEDTLS_SSL_COOKIE_C) || !defined(MBEDTLS_NET_C) || \
44 !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) || \
45 !defined(MBEDTLS_X509_CRT_PARSE_C) || !defined(MBEDTLS_RSA_C) || \
46 !defined(MBEDTLS_CERTS_C) || !defined(MBEDTLS_PEM_PARSE_C) || \
47 !defined(MBEDTLS_TIMING_C)
48
main(void)49 int main(void)
50 {
51 printf("MBEDTLS_SSL_SRV_C and/or MBEDTLS_SSL_PROTO_DTLS and/or "
52 "MBEDTLS_SSL_COOKIE_C and/or MBEDTLS_NET_C and/or "
53 "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C and/or "
54 "MBEDTLS_X509_CRT_PARSE_C and/or MBEDTLS_RSA_C and/or "
55 "MBEDTLS_CERTS_C and/or MBEDTLS_PEM_PARSE_C and/or "
56 "MBEDTLS_TIMING_C not defined.\n");
57 return(0);
58 }
59 #else
60
61 #if defined(_WIN32)
62 #include <windows.h>
63 #endif
64
65 #include <string.h>
66 #include <stdlib.h>
67 #include <stdio.h>
68
69 #include "mbedtls/entropy.h"
70 #include "mbedtls/ctr_drbg.h"
71 #include "mbedtls/certs.h"
72 #include "mbedtls/x509.h"
73 #include "mbedtls/ssl.h"
74 #include "mbedtls/ssl_cookie.h"
75 #include "mbedtls/net_sockets.h"
76 #include "mbedtls/error.h"
77 #include "mbedtls/debug.h"
78 #include "mbedtls/timing.h"
79
80 #if defined(MBEDTLS_SSL_CACHE_C)
81 #include "mbedtls/ssl_cache.h"
82 #endif
83
84 #define READ_TIMEOUT_MS 10000 /* 5 seconds */
85 #define DEBUG_LEVEL 0
86
87 extern int optind, opterr, optopt;
88 extern char *optarg;
89
90 static bool debug;
91 static bool help;
92
my_debug(void * ctx,int level,const char * file,int line,const char * str)93 static void my_debug(void *ctx, int level,
94 const char *file, int line,
95 const char *str)
96 {
97 ((void) level);
98
99 mbedtls_fprintf((FILE *) ctx, "%s:%04d: %s", file, line, str);
100 fflush( (FILE *) ctx );
101 }
102
main(int argc,char * argv[])103 int main(int argc, char *argv[])
104 {
105 int ret, len, c;
106 mbedtls_net_context listen_fd, client_fd;
107 unsigned char buf[1024];
108 const char *pers = "dtls_server";
109 unsigned char client_ip[16] = { 0 };
110 size_t cliip_len;
111 mbedtls_ssl_cookie_ctx cookie_ctx;
112
113 mbedtls_entropy_context entropy;
114 mbedtls_ctr_drbg_context ctr_drbg;
115 mbedtls_ssl_context ssl;
116 mbedtls_ssl_config conf;
117 mbedtls_x509_crt srvcert;
118 mbedtls_pk_context pkey;
119 mbedtls_timing_delay_context timer;
120 #if defined(MBEDTLS_SSL_CACHE_C)
121 mbedtls_ssl_cache_context cache;
122 #endif
123
124 #define LISTEN_PORT "4242"
125 const char *listen_port = LISTEN_PORT;
126
127 #define SRV_CERT_FILE "echo-apps-cert.pem"
128 const char *srv_cert_file = SRV_CERT_FILE;
129
130 #define SRV_KEY_FILE "echo-apps-key.pem"
131 const char *srv_key_file = SRV_KEY_FILE;
132
133 opterr = 0;
134
135 while ((c = getopt(argc, argv, "c:k:p:Dh")) != -1) {
136 switch (c) {
137 case 'c':
138 srv_cert_file = optarg;
139 break;
140 case 'k':
141 srv_key_file = optarg;
142 break;
143 case 'p':
144 listen_port = optarg;
145 break;
146 case 'D':
147 debug = true;
148 break;
149 case 'h':
150 help = true;
151 break;
152 }
153 }
154
155 if (help) {
156 printf("usage: %s [-c <server cert file>] [-k <cert key file>] "
157 "[-p <port>] [-D]\n", argv[0]);
158 printf("-c Server cert file (default is %s)\n", SRV_CERT_FILE);
159 printf("-k Server key file (default is %s)\n", SRV_KEY_FILE);
160 printf("-p Port number to use (default is %s)\n", LISTEN_PORT);
161 printf("-D Activate debugging.\n");
162 exit(-EINVAL);
163 }
164
165 mbedtls_net_init(&listen_fd);
166 mbedtls_net_init(&client_fd);
167 mbedtls_ssl_init(&ssl);
168 mbedtls_ssl_config_init(&conf);
169 mbedtls_ssl_cookie_init(&cookie_ctx);
170 #if defined(MBEDTLS_SSL_CACHE_C)
171 mbedtls_ssl_cache_init(&cache);
172 #endif
173 mbedtls_x509_crt_init(&srvcert);
174 mbedtls_pk_init(&pkey);
175 mbedtls_entropy_init(&entropy);
176 mbedtls_ctr_drbg_init(&ctr_drbg);
177
178 #if defined(MBEDTLS_DEBUG_C)
179 mbedtls_debug_set_threshold(DEBUG_LEVEL);
180 #endif
181
182 /*
183 * 1. Load the certificates and private RSA key
184 */
185 printf("\n . Loading the server cert. and key...");
186 fflush(stdout);
187
188 ret = mbedtls_x509_crt_parse_file(&srvcert, srv_cert_file);
189 if (ret != 0) {
190 printf(" failed\n ! mbedtls_x509_crt_parse returned %d\n\n",
191 ret);
192 goto exit;
193 }
194
195 ret = mbedtls_pk_parse_keyfile(&pkey, srv_key_file, NULL);
196 if (ret != 0) {
197 printf(" failed\n ! mbedtls_pk_parse_keyfile returned %d\n\n",
198 ret);
199 goto exit;
200 }
201
202 printf(" ok\n");
203
204 /*
205 * 2. Setup the "listening" UDP socket
206 */
207 printf(" . Bind on udp/*/%s ...", listen_port);
208 fflush(stdout);
209
210 if ((ret = mbedtls_net_bind(&listen_fd, NULL, listen_port,
211 MBEDTLS_NET_PROTO_UDP)) != 0) {
212 printf(" failed\n ! mbedtls_net_bind returned %d\n\n", ret);
213 goto exit;
214 }
215
216 printf(" ok\n");
217
218 /*
219 * 3. Seed the RNG
220 */
221 printf(" . Seeding the random number generator...");
222 fflush(stdout);
223
224 if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func,
225 &entropy,
226 (const unsigned char *) pers,
227 strlen(pers))) != 0) {
228 printf(" failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret);
229 goto exit;
230 }
231
232 printf(" ok\n");
233
234 /*
235 * 4. Setup stuff
236 */
237 printf(" . Setting up the DTLS data...");
238 fflush(stdout);
239
240 if ((ret = mbedtls_ssl_config_defaults(&conf,
241 MBEDTLS_SSL_IS_SERVER,
242 MBEDTLS_SSL_TRANSPORT_DATAGRAM,
243 MBEDTLS_SSL_PRESET_DEFAULT)) != 0) {
244 mbedtls_printf(" failed\n ! mbedtls_ssl_config_defaults "
245 "returned %d\n\n", ret);
246 goto exit;
247 }
248
249 mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
250 mbedtls_ssl_conf_dbg(&conf, my_debug, stdout);
251
252 #if defined(MBEDTLS_SSL_CACHE_C)
253 mbedtls_ssl_conf_session_cache(&conf, &cache,
254 mbedtls_ssl_cache_get,
255 mbedtls_ssl_cache_set);
256 #endif
257
258 mbedtls_ssl_conf_ca_chain(&conf, srvcert.next, NULL);
259 if ((ret = mbedtls_ssl_conf_own_cert(&conf, &srvcert, &pkey)) != 0) {
260 printf(" failed\n ! mbedtls_ssl_conf_own_cert "
261 "returned %d\n\n", ret);
262 goto exit;
263 }
264
265 if ((ret = mbedtls_ssl_cookie_setup(&cookie_ctx,
266 mbedtls_ctr_drbg_random,
267 &ctr_drbg)) != 0) {
268 printf(" failed\n ! mbedtls_ssl_cookie_setup returned %d\n\n",
269 ret);
270 goto exit;
271 }
272
273 mbedtls_ssl_conf_dtls_cookies(&conf, mbedtls_ssl_cookie_write,
274 mbedtls_ssl_cookie_check, &cookie_ctx);
275
276 if ((ret = mbedtls_ssl_setup(&ssl, &conf)) != 0) {
277 printf(" failed\n ! mbedtls_ssl_setup returned %d\n\n", ret);
278 goto exit;
279 }
280
281 mbedtls_ssl_set_timer_cb(&ssl, &timer, mbedtls_timing_set_delay,
282 mbedtls_timing_get_delay);
283
284 printf(" ok\n");
285
286 reset:
287 #ifdef MBEDTLS_ERROR_C
288 if (ret != 0) {
289 char error_buf[100];
290 mbedtls_strerror(ret, error_buf, 100);
291 printf("Last error was: %d - %s\n\n", ret, error_buf);
292 }
293 #endif
294
295 mbedtls_net_free(&client_fd);
296
297 mbedtls_ssl_session_reset(&ssl);
298
299 /*
300 * 3. Wait until a client connects
301 */
302 printf(" . Waiting for a remote connection ...");
303 fflush(stdout);
304
305 if ((ret = mbedtls_net_accept(&listen_fd, &client_fd,
306 client_ip, sizeof(client_ip),
307 &cliip_len)) != 0) {
308 printf(" failed\n ! mbedtls_net_accept returned %d\n\n", ret);
309 goto exit;
310 }
311
312 /* For HelloVerifyRequest cookies */
313 if ((ret = mbedtls_ssl_set_client_transport_id(&ssl,
314 client_ip,
315 cliip_len)) != 0) {
316 printf(" failed\n ! "
317 "mbedtls_ssl_set_client_transport_id() "
318 "returned -0x%x\n\n", -ret);
319 goto exit;
320 }
321
322 mbedtls_ssl_set_bio(&ssl, &client_fd,
323 mbedtls_net_send, mbedtls_net_recv,
324 mbedtls_net_recv_timeout);
325
326 printf(" ok\n");
327
328 /*
329 * 5. Handshake
330 */
331 printf(" . Performing the DTLS handshake...");
332 fflush(stdout);
333
334 do ret = mbedtls_ssl_handshake(&ssl);
335 while(ret == MBEDTLS_ERR_SSL_WANT_READ ||
336 ret == MBEDTLS_ERR_SSL_WANT_WRITE);
337
338 if (ret == MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED) {
339 printf(" hello verification requested\n");
340 ret = 0;
341 goto reset;
342 }
343 else if (ret != 0)
344 {
345 printf(" failed\n ! mbedtls_ssl_handshake returned -0x%x\n\n",
346 -ret);
347 goto reset;
348 }
349
350 printf(" ok\n");
351
352 again:
353 /*
354 * 6. Read the echo Request
355 */
356 printf(" < Read from client:");
357 fflush(stdout);
358
359 len = sizeof(buf) - 1;
360 memset(buf, 0, sizeof(buf));
361
362 do ret = mbedtls_ssl_read(&ssl, buf, len);
363 while(ret == MBEDTLS_ERR_SSL_WANT_READ ||
364 ret == MBEDTLS_ERR_SSL_WANT_WRITE);
365
366 if (ret <= 0) {
367 switch(ret) {
368 case MBEDTLS_ERR_SSL_TIMEOUT:
369 printf(" timeout\n\n");
370 goto reset;
371
372 case MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY:
373 printf(" connection was closed gracefully\n");
374 ret = 0;
375 goto close_notify;
376
377 default:
378 printf(" mbedtls_ssl_read returned -0x%x\n\n", -ret);
379 goto reset;
380 }
381 }
382
383 len = ret;
384 printf(" %d bytes read\n\n%s\n\n", len, buf);
385
386 /*
387 * 7. Write the 200 Response
388 */
389 printf(" > Write to client:");
390 fflush(stdout);
391
392 do ret = mbedtls_ssl_write(&ssl, buf, len);
393 while(ret == MBEDTLS_ERR_SSL_WANT_READ ||
394 ret == MBEDTLS_ERR_SSL_WANT_WRITE);
395
396 if (ret < 0) {
397 printf(" failed\n ! mbedtls_ssl_write returned %d\n\n", ret);
398 goto exit;
399 }
400
401 len = ret;
402 printf(" %d bytes written\n\n%s\n\n", len, buf);
403
404 goto again;
405
406 /*
407 * 8. Done, cleanly close the connection
408 */
409 close_notify:
410 printf(" . Closing the connection...");
411
412 /* No error checking, the connection might be closed already */
413 do ret = mbedtls_ssl_close_notify(&ssl);
414 while(ret == MBEDTLS_ERR_SSL_WANT_WRITE);
415 ret = 0;
416
417 printf(" done\n");
418
419 goto reset;
420
421 /*
422 * Final clean-ups and exit
423 */
424 exit:
425
426 #ifdef MBEDTLS_ERROR_C
427 if (ret != 0) {
428 char error_buf[100];
429 mbedtls_strerror(ret, error_buf, 100);
430 printf("Last error was: %d - %s\n\n", ret, error_buf);
431 }
432 #endif
433
434 mbedtls_net_free(&client_fd);
435 mbedtls_net_free(&listen_fd);
436
437 mbedtls_x509_crt_free(&srvcert);
438 mbedtls_pk_free(&pkey);
439 mbedtls_ssl_free(&ssl);
440 mbedtls_ssl_config_free(&conf);
441 mbedtls_ssl_cookie_free(&cookie_ctx);
442 #if defined(MBEDTLS_SSL_CACHE_C)
443 mbedtls_ssl_cache_free(&cache);
444 #endif
445 mbedtls_ctr_drbg_free(&ctr_drbg);
446 mbedtls_entropy_free(&entropy);
447
448 #if defined(_WIN32)
449 printf(" Press Enter to exit this program.\n");
450 fflush(stdout); getchar();
451 #endif
452
453 /* Shell can not handle large exit numbers -> 1 for errors */
454 if (ret < 0)
455 ret = 1;
456
457 return(ret);
458 }
459 #endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_PROTO_DTLS &&
460 MBEDTLS_SSL_COOKIE_C && MBEDTLS_NET_C && MBEDTLS_ENTROPY_C &&
461 MBEDTLS_CTR_DRBG_C && MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_RSA_C
462 && MBEDTLS_CERTS_C && MBEDTLS_PEM_PARSE_C && MBEDTLS_TIMING_C */
463
