1 /*
2 * Simple DTLS server demonstration program
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7
8 #if !defined(MBEDTLS_CONFIG_FILE)
9 #include "mbedtls/config.h"
10 #else
11 #include MBEDTLS_CONFIG_FILE
12 #endif
13
14 #include "mbedtls/platform.h"
15
16 /* Uncomment out the following line to default to IPv4 and disable IPv6 */
17 //#define FORCE_IPV4
18
19 #ifdef FORCE_IPV4
20 #define BIND_IP "0.0.0.0" /* Forces IPv4 */
21 #else
22 #define BIND_IP "::"
23 #endif
24
25 #if !defined(MBEDTLS_SSL_SRV_C) || !defined(MBEDTLS_SSL_PROTO_DTLS) || \
26 !defined(MBEDTLS_SSL_COOKIE_C) || !defined(MBEDTLS_NET_C) || \
27 !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) || \
28 !defined(MBEDTLS_X509_CRT_PARSE_C) || !defined(MBEDTLS_RSA_C) || \
29 !defined(MBEDTLS_CERTS_C) || !defined(MBEDTLS_PEM_PARSE_C) || \
30 !defined(MBEDTLS_TIMING_C)
31
main(void)32 int main(void)
33 {
34 printf("MBEDTLS_SSL_SRV_C and/or MBEDTLS_SSL_PROTO_DTLS and/or "
35 "MBEDTLS_SSL_COOKIE_C and/or MBEDTLS_NET_C and/or "
36 "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C and/or "
37 "MBEDTLS_X509_CRT_PARSE_C and/or MBEDTLS_RSA_C and/or "
38 "MBEDTLS_CERTS_C and/or MBEDTLS_PEM_PARSE_C and/or "
39 "MBEDTLS_TIMING_C not defined.\n");
40 mbedtls_exit(0);
41 }
42 #else
43
44 #if defined(_WIN32)
45 #include <windows.h>
46 #endif
47
48 #include <string.h>
49 #include <stdlib.h>
50 #include <stdio.h>
51
52 #include "mbedtls/entropy.h"
53 #include "mbedtls/ctr_drbg.h"
54 #include "mbedtls/certs.h"
55 #include "mbedtls/x509.h"
56 #include "mbedtls/ssl.h"
57 #include "mbedtls/ssl_cookie.h"
58 #include "mbedtls/net_sockets.h"
59 #include "mbedtls/error.h"
60 #include "mbedtls/debug.h"
61 #include "mbedtls/timing.h"
62
63 #if defined(MBEDTLS_SSL_CACHE_C)
64 #include "mbedtls/ssl_cache.h"
65 #endif
66
67 #define READ_TIMEOUT_MS 10000 /* 10 seconds */
68 #define DEBUG_LEVEL 0
69
70
my_debug(void * ctx,int level,const char * file,int line,const char * str)71 static void my_debug(void *ctx, int level,
72 const char *file, int line,
73 const char *str)
74 {
75 ((void) level);
76
77 mbedtls_fprintf((FILE *) ctx, "%s:%04d: %s", file, line, str);
78 fflush((FILE *) ctx);
79 }
80
main(void)81 int main(void)
82 {
83 int ret, len;
84 mbedtls_net_context listen_fd, client_fd;
85 unsigned char buf[1024];
86 const char *pers = "dtls_server";
87 unsigned char client_ip[16] = { 0 };
88 size_t cliip_len;
89 mbedtls_ssl_cookie_ctx cookie_ctx;
90
91 mbedtls_entropy_context entropy;
92 mbedtls_ctr_drbg_context ctr_drbg;
93 mbedtls_ssl_context ssl;
94 mbedtls_ssl_config conf;
95 mbedtls_x509_crt srvcert;
96 mbedtls_pk_context pkey;
97 mbedtls_timing_delay_context timer;
98 #if defined(MBEDTLS_SSL_CACHE_C)
99 mbedtls_ssl_cache_context cache;
100 #endif
101
102 mbedtls_net_init(&listen_fd);
103 mbedtls_net_init(&client_fd);
104 mbedtls_ssl_init(&ssl);
105 mbedtls_ssl_config_init(&conf);
106 mbedtls_ssl_cookie_init(&cookie_ctx);
107 #if defined(MBEDTLS_SSL_CACHE_C)
108 mbedtls_ssl_cache_init(&cache);
109 #endif
110 mbedtls_x509_crt_init(&srvcert);
111 mbedtls_pk_init(&pkey);
112 mbedtls_entropy_init(&entropy);
113 mbedtls_ctr_drbg_init(&ctr_drbg);
114
115 #if defined(MBEDTLS_USE_PSA_CRYPTO)
116 psa_status_t status = psa_crypto_init();
117 if (status != PSA_SUCCESS) {
118 mbedtls_fprintf(stderr, "Failed to initialize PSA Crypto implementation: %d\n",
119 (int) status);
120 ret = MBEDTLS_ERR_SSL_HW_ACCEL_FAILED;
121 goto exit;
122 }
123 #endif /* MBEDTLS_USE_PSA_CRYPTO */
124
125 #if defined(MBEDTLS_DEBUG_C)
126 mbedtls_debug_set_threshold(DEBUG_LEVEL);
127 #endif
128
129 /*
130 * 1. Load the certificates and private RSA key
131 */
132 printf("\n . Loading the server cert. and key...");
133 fflush(stdout);
134
135 /*
136 * This demonstration program uses embedded test certificates.
137 * Instead, you may want to use mbedtls_x509_crt_parse_file() to read the
138 * server and CA certificates, as well as mbedtls_pk_parse_keyfile().
139 */
140 ret = mbedtls_x509_crt_parse(&srvcert, (const unsigned char *) mbedtls_test_srv_crt,
141 mbedtls_test_srv_crt_len);
142 if (ret != 0) {
143 printf(" failed\n ! mbedtls_x509_crt_parse returned %d\n\n", ret);
144 goto exit;
145 }
146
147 ret = mbedtls_x509_crt_parse(&srvcert, (const unsigned char *) mbedtls_test_cas_pem,
148 mbedtls_test_cas_pem_len);
149 if (ret != 0) {
150 printf(" failed\n ! mbedtls_x509_crt_parse returned %d\n\n", ret);
151 goto exit;
152 }
153
154 ret = mbedtls_pk_parse_key(&pkey, (const unsigned char *) mbedtls_test_srv_key,
155 mbedtls_test_srv_key_len, NULL, 0);
156 if (ret != 0) {
157 printf(" failed\n ! mbedtls_pk_parse_key returned %d\n\n", ret);
158 goto exit;
159 }
160
161 printf(" ok\n");
162
163 /*
164 * 2. Setup the "listening" UDP socket
165 */
166 printf(" . Bind on udp/*/4433 ...");
167 fflush(stdout);
168
169 if ((ret = mbedtls_net_bind(&listen_fd, BIND_IP, "4433", MBEDTLS_NET_PROTO_UDP)) != 0) {
170 printf(" failed\n ! mbedtls_net_bind returned %d\n\n", ret);
171 goto exit;
172 }
173
174 printf(" ok\n");
175
176 /*
177 * 3. Seed the RNG
178 */
179 printf(" . Seeding the random number generator...");
180 fflush(stdout);
181
182 if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
183 (const unsigned char *) pers,
184 strlen(pers))) != 0) {
185 printf(" failed\n ! mbedtls_ctr_drbg_seed returned %d\n", ret);
186 goto exit;
187 }
188
189 printf(" ok\n");
190
191 /*
192 * 4. Setup stuff
193 */
194 printf(" . Setting up the DTLS data...");
195 fflush(stdout);
196
197 if ((ret = mbedtls_ssl_config_defaults(&conf,
198 MBEDTLS_SSL_IS_SERVER,
199 MBEDTLS_SSL_TRANSPORT_DATAGRAM,
200 MBEDTLS_SSL_PRESET_DEFAULT)) != 0) {
201 mbedtls_printf(" failed\n ! mbedtls_ssl_config_defaults returned %d\n\n", ret);
202 goto exit;
203 }
204
205 mbedtls_ssl_conf_rng(&conf, mbedtls_ctr_drbg_random, &ctr_drbg);
206 mbedtls_ssl_conf_dbg(&conf, my_debug, stdout);
207 mbedtls_ssl_conf_read_timeout(&conf, READ_TIMEOUT_MS);
208
209 #if defined(MBEDTLS_SSL_CACHE_C)
210 mbedtls_ssl_conf_session_cache(&conf, &cache,
211 mbedtls_ssl_cache_get,
212 mbedtls_ssl_cache_set);
213 #endif
214
215 mbedtls_ssl_conf_ca_chain(&conf, srvcert.next, NULL);
216 if ((ret = mbedtls_ssl_conf_own_cert(&conf, &srvcert, &pkey)) != 0) {
217 printf(" failed\n ! mbedtls_ssl_conf_own_cert returned %d\n\n", ret);
218 goto exit;
219 }
220
221 if ((ret = mbedtls_ssl_cookie_setup(&cookie_ctx,
222 mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
223 printf(" failed\n ! mbedtls_ssl_cookie_setup returned %d\n\n", ret);
224 goto exit;
225 }
226
227 mbedtls_ssl_conf_dtls_cookies(&conf, mbedtls_ssl_cookie_write, mbedtls_ssl_cookie_check,
228 &cookie_ctx);
229
230 if ((ret = mbedtls_ssl_setup(&ssl, &conf)) != 0) {
231 printf(" failed\n ! mbedtls_ssl_setup returned %d\n\n", ret);
232 goto exit;
233 }
234
235 mbedtls_ssl_set_timer_cb(&ssl, &timer, mbedtls_timing_set_delay,
236 mbedtls_timing_get_delay);
237
238 printf(" ok\n");
239
240 reset:
241 #ifdef MBEDTLS_ERROR_C
242 if (ret != 0) {
243 char error_buf[100];
244 mbedtls_strerror(ret, error_buf, 100);
245 printf("Last error was: %d - %s\n\n", ret, error_buf);
246 }
247 #endif
248
249 mbedtls_net_free(&client_fd);
250
251 mbedtls_ssl_session_reset(&ssl);
252
253 /*
254 * 3. Wait until a client connects
255 */
256 printf(" . Waiting for a remote connection ...");
257 fflush(stdout);
258
259 if ((ret = mbedtls_net_accept(&listen_fd, &client_fd,
260 client_ip, sizeof(client_ip), &cliip_len)) != 0) {
261 printf(" failed\n ! mbedtls_net_accept returned %d\n\n", ret);
262 goto exit;
263 }
264
265 /* For HelloVerifyRequest cookies */
266 if ((ret = mbedtls_ssl_set_client_transport_id(&ssl,
267 client_ip, cliip_len)) != 0) {
268 printf(" failed\n ! "
269 "mbedtls_ssl_set_client_transport_id() returned -0x%x\n\n", (unsigned int) -ret);
270 goto exit;
271 }
272
273 mbedtls_ssl_set_bio(&ssl, &client_fd,
274 mbedtls_net_send, mbedtls_net_recv, mbedtls_net_recv_timeout);
275
276 printf(" ok\n");
277
278 /*
279 * 5. Handshake
280 */
281 printf(" . Performing the DTLS handshake...");
282 fflush(stdout);
283
284 do {
285 ret = mbedtls_ssl_handshake(&ssl);
286 } while (ret == MBEDTLS_ERR_SSL_WANT_READ ||
287 ret == MBEDTLS_ERR_SSL_WANT_WRITE);
288
289 if (ret == MBEDTLS_ERR_SSL_HELLO_VERIFY_REQUIRED) {
290 printf(" hello verification requested\n");
291 ret = 0;
292 goto reset;
293 } else if (ret != 0) {
294 printf(" failed\n ! mbedtls_ssl_handshake returned -0x%x\n\n", (unsigned int) -ret);
295 goto reset;
296 }
297
298 printf(" ok\n");
299
300 /*
301 * 6. Read the echo Request
302 */
303 printf(" < Read from client:");
304 fflush(stdout);
305
306 len = sizeof(buf) - 1;
307 memset(buf, 0, sizeof(buf));
308
309 do {
310 ret = mbedtls_ssl_read(&ssl, buf, len);
311 } while (ret == MBEDTLS_ERR_SSL_WANT_READ ||
312 ret == MBEDTLS_ERR_SSL_WANT_WRITE);
313
314 if (ret <= 0) {
315 switch (ret) {
316 case MBEDTLS_ERR_SSL_TIMEOUT:
317 printf(" timeout\n\n");
318 goto reset;
319
320 case MBEDTLS_ERR_SSL_PEER_CLOSE_NOTIFY:
321 printf(" connection was closed gracefully\n");
322 goto close_notify;
323
324 default:
325 printf(" mbedtls_ssl_read returned -0x%x\n\n", (unsigned int) -ret);
326 goto reset;
327 }
328 }
329
330 len = ret;
331 printf(" %d bytes read\n\n%s\n\n", len, buf);
332
333 /*
334 * 7. Write the 200 Response
335 */
336 printf(" > Write to client:");
337 fflush(stdout);
338
339 do {
340 ret = mbedtls_ssl_write(&ssl, buf, len);
341 } while (ret == MBEDTLS_ERR_SSL_WANT_READ ||
342 ret == MBEDTLS_ERR_SSL_WANT_WRITE);
343
344 if (ret < 0) {
345 printf(" failed\n ! mbedtls_ssl_write returned %d\n\n", ret);
346 goto exit;
347 }
348
349 len = ret;
350 printf(" %d bytes written\n\n%s\n\n", len, buf);
351
352 /*
353 * 8. Done, cleanly close the connection
354 */
355 close_notify:
356 printf(" . Closing the connection...");
357
358 /* No error checking, the connection might be closed already */
359 do {
360 ret = mbedtls_ssl_close_notify(&ssl);
361 } while (ret == MBEDTLS_ERR_SSL_WANT_WRITE);
362 ret = 0;
363
364 printf(" done\n");
365
366 goto reset;
367
368 /*
369 * Final clean-ups and exit
370 */
371 exit:
372
373 #ifdef MBEDTLS_ERROR_C
374 if (ret != 0) {
375 char error_buf[100];
376 mbedtls_strerror(ret, error_buf, 100);
377 printf("Last error was: %d - %s\n\n", ret, error_buf);
378 }
379 #endif
380
381 mbedtls_net_free(&client_fd);
382 mbedtls_net_free(&listen_fd);
383
384 mbedtls_x509_crt_free(&srvcert);
385 mbedtls_pk_free(&pkey);
386 mbedtls_ssl_free(&ssl);
387 mbedtls_ssl_config_free(&conf);
388 mbedtls_ssl_cookie_free(&cookie_ctx);
389 #if defined(MBEDTLS_SSL_CACHE_C)
390 mbedtls_ssl_cache_free(&cache);
391 #endif
392 mbedtls_ctr_drbg_free(&ctr_drbg);
393 mbedtls_entropy_free(&entropy);
394 #if defined(MBEDTLS_USE_PSA_CRYPTO)
395 mbedtls_psa_crypto_free();
396 #endif /* MBEDTLS_USE_PSA_CRYPTO */
397
398 #if defined(_WIN32)
399 printf(" Press Enter to exit this program.\n");
400 fflush(stdout); getchar();
401 #endif
402
403 /* Shell can not handle large exit numbers -> 1 for errors */
404 if (ret < 0) {
405 ret = 1;
406 }
407
408 mbedtls_exit(ret);
409 }
410 #endif /* MBEDTLS_SSL_SRV_C && MBEDTLS_SSL_PROTO_DTLS &&
411 MBEDTLS_SSL_COOKIE_C && MBEDTLS_NET_C && MBEDTLS_ENTROPY_C &&
412 MBEDTLS_CTR_DRBG_C && MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_RSA_C
413 && MBEDTLS_CERTS_C && MBEDTLS_PEM_PARSE_C && MBEDTLS_TIMING_C */
414