1 /* crypto/bio/bio_dgram.c */
2 /*
3 * DTLS implementation written by Nagendra Modadugu
4 * (nagendra@cs.stanford.edu) for the OpenSSL project 2005.
5 */
6 /* ====================================================================
7 * Copyright (c) 1999-2005 The OpenSSL Project. All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 *
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in
18 * the documentation and/or other materials provided with the
19 * distribution.
20 *
21 * 3. All advertising materials mentioning features or use of this
22 * software must display the following acknowledgment:
23 * "This product includes software developed by the OpenSSL Project
24 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 *
26 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 * endorse or promote products derived from this software without
28 * prior written permission. For written permission, please contact
29 * openssl-core@OpenSSL.org.
30 *
31 * 5. Products derived from this software may not be called "OpenSSL"
32 * nor may "OpenSSL" appear in their names without prior written
33 * permission of the OpenSSL Project.
34 *
35 * 6. Redistributions of any form whatsoever must retain the following
36 * acknowledgment:
37 * "This product includes software developed by the OpenSSL Project
38 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 *
40 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 * OF THE POSSIBILITY OF SUCH DAMAGE.
52 * ====================================================================
53 *
54 * This product includes cryptographic software written by Eric Young
55 * (eay@cryptsoft.com). This product includes software written by Tim
56 * Hudson (tjh@cryptsoft.com).
57 *
58 */
59
60 #ifndef OPENSSL_NO_DGRAM
61
62 #include <stdio.h>
63 #include <errno.h>
64 #define USE_SOCKETS
65 #include "cryptlib.h"
66
67 #include <openssl/bio.h>
68
69 #define IP_MTU 14 /* linux is lame */
70
71 #ifdef WATT32
72 #define sock_write SockWrite /* Watt-32 uses same names */
73 #define sock_read SockRead
74 #define sock_puts SockPuts
75 #endif
76
77 static int dgram_write(BIO *h, const char *buf, int num);
78 static int dgram_read(BIO *h, char *buf, int size);
79 static int dgram_puts(BIO *h, const char *str);
80 static long dgram_ctrl(BIO *h, int cmd, long arg1, void *arg2);
81 static int dgram_new(BIO *h);
82 static int dgram_free(BIO *data);
83 static int dgram_clear(BIO *bio);
84
85 int BIO_dgram_should_retry(int s);
86
87 static BIO_METHOD methods_dgramp=
88 {
89 BIO_TYPE_DGRAM,
90 "datagram socket",
91 dgram_write,
92 dgram_read,
93 dgram_puts,
94 NULL, /* dgram_gets, */
95 dgram_ctrl,
96 dgram_new,
97 dgram_free,
98 NULL,
99 };
100
101 typedef struct bio_dgram_data_st
102 {
103 struct sockaddr peer;
104 unsigned int connected;
105 unsigned int _errno;
106 unsigned int mtu;
107 } bio_dgram_data;
108
BIO_s_datagram(void)109 BIO_METHOD *BIO_s_datagram(void)
110 {
111 return(&methods_dgramp);
112 }
113
BIO_new_dgram(int fd,int close_flag)114 BIO *BIO_new_dgram(int fd, int close_flag)
115 {
116 BIO *ret;
117
118 ret=BIO_new(BIO_s_datagram());
119 if (ret == NULL) return(NULL);
120 BIO_set_fd(ret,fd,close_flag);
121 return(ret);
122 }
123
dgram_new(BIO * bi)124 static int dgram_new(BIO *bi)
125 {
126 bio_dgram_data *data = NULL;
127
128 bi->init=0;
129 bi->num=0;
130 data = OPENSSL_malloc(sizeof(bio_dgram_data));
131 if (data == NULL)
132 return 0;
133 memset(data, 0x00, sizeof(bio_dgram_data));
134 bi->ptr = data;
135
136 bi->flags=0;
137 return(1);
138 }
139
dgram_free(BIO * a)140 static int dgram_free(BIO *a)
141 {
142 bio_dgram_data *data;
143
144 if (a == NULL) return(0);
145 if ( ! dgram_clear(a))
146 return 0;
147
148 data = (bio_dgram_data *)a->ptr;
149 if(data != NULL) OPENSSL_free(data);
150
151 return(1);
152 }
153
dgram_clear(BIO * a)154 static int dgram_clear(BIO *a)
155 {
156 if (a == NULL) return(0);
157 if (a->shutdown)
158 {
159 if (a->init)
160 {
161 SHUTDOWN2(a->num);
162 }
163 a->init=0;
164 a->flags=0;
165 }
166 return(1);
167 }
168
dgram_read(BIO * b,char * out,int outl)169 static int dgram_read(BIO *b, char *out, int outl)
170 {
171 int ret=0;
172 bio_dgram_data *data = (bio_dgram_data *)b->ptr;
173
174 struct sockaddr peer;
175 int peerlen = sizeof(peer);
176
177 if (out != NULL)
178 {
179 clear_socket_error();
180 memset(&peer, 0x00, peerlen);
181 /* Last arg in recvfrom is signed on some platforms and
182 * unsigned on others. It is of type socklen_t on some
183 * but this is not universal. Cast to (void *) to avoid
184 * compiler warnings.
185 */
186 ret=recvfrom(b->num,out,outl,0,&peer,(void *)&peerlen);
187
188 if ( ! data->connected && ret > 0)
189 BIO_ctrl(b, BIO_CTRL_DGRAM_CONNECT, 0, &peer);
190
191 BIO_clear_retry_flags(b);
192 if (ret <= 0)
193 {
194 if (BIO_dgram_should_retry(ret))
195 {
196 BIO_set_retry_read(b);
197 data->_errno = get_last_socket_error();
198 }
199 }
200 }
201 return(ret);
202 }
203
dgram_write(BIO * b,const char * in,int inl)204 static int dgram_write(BIO *b, const char *in, int inl)
205 {
206 int ret;
207 bio_dgram_data *data = (bio_dgram_data *)b->ptr;
208 clear_socket_error();
209
210 if ( data->connected )
211 ret=send(b->num,in,inl,0);
212 else
213 ret=sendto(b->num, in, inl, 0, &data->peer, sizeof(data->peer));
214
215 BIO_clear_retry_flags(b);
216 if (ret <= 0)
217 {
218 if (BIO_sock_should_retry(ret))
219 {
220 BIO_set_retry_write(b);
221 data->_errno = get_last_socket_error();
222
223 #if 0 /* higher layers are responsible for querying MTU, if necessary */
224 if ( data->_errno == EMSGSIZE)
225 /* retrieve the new MTU */
226 BIO_ctrl(b, BIO_CTRL_DGRAM_QUERY_MTU, 0, NULL);
227 #endif
228 }
229 }
230 return(ret);
231 }
232
dgram_ctrl(BIO * b,int cmd,long num,void * ptr)233 static long dgram_ctrl(BIO *b, int cmd, long num, void *ptr)
234 {
235 long ret=1;
236 int *ip;
237 struct sockaddr *to = NULL;
238 bio_dgram_data *data = NULL;
239 long sockopt_val = 0;
240 unsigned int sockopt_len = 0;
241
242 data = (bio_dgram_data *)b->ptr;
243
244 switch (cmd)
245 {
246 case BIO_CTRL_RESET:
247 num=0;
248 case BIO_C_FILE_SEEK:
249 ret=0;
250 break;
251 case BIO_C_FILE_TELL:
252 case BIO_CTRL_INFO:
253 ret=0;
254 break;
255 case BIO_C_SET_FD:
256 dgram_clear(b);
257 b->num= *((int *)ptr);
258 b->shutdown=(int)num;
259 b->init=1;
260 break;
261 case BIO_C_GET_FD:
262 if (b->init)
263 {
264 ip=(int *)ptr;
265 if (ip != NULL) *ip=b->num;
266 ret=b->num;
267 }
268 else
269 ret= -1;
270 break;
271 case BIO_CTRL_GET_CLOSE:
272 ret=b->shutdown;
273 break;
274 case BIO_CTRL_SET_CLOSE:
275 b->shutdown=(int)num;
276 break;
277 case BIO_CTRL_PENDING:
278 case BIO_CTRL_WPENDING:
279 ret=0;
280 break;
281 case BIO_CTRL_DUP:
282 case BIO_CTRL_FLUSH:
283 ret=1;
284 break;
285 case BIO_CTRL_DGRAM_CONNECT:
286 to = (struct sockaddr *)ptr;
287 #if 0
288 if (connect(b->num, to, sizeof(struct sockaddr)) < 0)
289 { perror("connect"); ret = 0; }
290 else
291 {
292 #endif
293 memcpy(&(data->peer),to, sizeof(struct sockaddr));
294 #if 0
295 }
296 #endif
297 break;
298 /* (Linux)kernel sets DF bit on outgoing IP packets */
299 #ifdef IP_MTU_DISCOVER
300 case BIO_CTRL_DGRAM_MTU_DISCOVER:
301 sockopt_val = IP_PMTUDISC_DO;
302 if ((ret = setsockopt(b->num, IPPROTO_IP, IP_MTU_DISCOVER,
303 &sockopt_val, sizeof(sockopt_val))) < 0)
304 perror("setsockopt");
305 break;
306 #endif
307 case BIO_CTRL_DGRAM_QUERY_MTU:
308 sockopt_len = sizeof(sockopt_val);
309 if ((ret = getsockopt(b->num, IPPROTO_IP, IP_MTU, (void *)&sockopt_val,
310 &sockopt_len)) < 0 || sockopt_val < 0)
311 { ret = 0; }
312 else
313 {
314 data->mtu = sockopt_val;
315 ret = data->mtu;
316 }
317 break;
318 case BIO_CTRL_DGRAM_GET_MTU:
319 return data->mtu;
320 break;
321 case BIO_CTRL_DGRAM_SET_MTU:
322 data->mtu = num;
323 ret = num;
324 break;
325 case BIO_CTRL_DGRAM_SET_CONNECTED:
326 to = (struct sockaddr *)ptr;
327
328 if ( to != NULL)
329 {
330 data->connected = 1;
331 memcpy(&(data->peer),to, sizeof(struct sockaddr));
332 }
333 else
334 {
335 data->connected = 0;
336 memset(&(data->peer), 0x00, sizeof(struct sockaddr));
337 }
338 break;
339 case BIO_CTRL_DGRAM_SET_PEER:
340 to = (struct sockaddr *) ptr;
341
342 memcpy(&(data->peer), to, sizeof(struct sockaddr));
343 break;
344 case BIO_CTRL_DGRAM_SET_RECV_TIMEOUT:
345 if ( setsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO, ptr,
346 sizeof(struct timeval)) < 0)
347 { perror("setsockopt"); ret = -1; }
348 break;
349 case BIO_CTRL_DGRAM_GET_RECV_TIMEOUT:
350 if ( getsockopt(b->num, SOL_SOCKET, SO_RCVTIMEO,
351 ptr, (void *)&ret) < 0)
352 { perror("getsockopt"); ret = -1; }
353 break;
354 case BIO_CTRL_DGRAM_SET_SEND_TIMEOUT:
355 if ( setsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO, ptr,
356 sizeof(struct timeval)) < 0)
357 { perror("setsockopt"); ret = -1; }
358 break;
359 case BIO_CTRL_DGRAM_GET_SEND_TIMEOUT:
360 if ( getsockopt(b->num, SOL_SOCKET, SO_SNDTIMEO,
361 ptr, (void *)&ret) < 0)
362 { perror("getsockopt"); ret = -1; }
363 break;
364 case BIO_CTRL_DGRAM_GET_SEND_TIMER_EXP:
365 /* fall-through */
366 case BIO_CTRL_DGRAM_GET_RECV_TIMER_EXP:
367 if ( data->_errno == EAGAIN)
368 {
369 ret = 1;
370 data->_errno = 0;
371 }
372 else
373 ret = 0;
374 break;
375 #ifdef EMSGSIZE
376 case BIO_CTRL_DGRAM_MTU_EXCEEDED:
377 if ( data->_errno == EMSGSIZE)
378 {
379 ret = 1;
380 data->_errno = 0;
381 }
382 else
383 ret = 0;
384 break;
385 #endif
386 default:
387 ret=0;
388 break;
389 }
390 return(ret);
391 }
392
dgram_puts(BIO * bp,const char * str)393 static int dgram_puts(BIO *bp, const char *str)
394 {
395 int n,ret;
396
397 n=strlen(str);
398 ret=dgram_write(bp,str,n);
399 return(ret);
400 }
401
BIO_dgram_should_retry(int i)402 int BIO_dgram_should_retry(int i)
403 {
404 int err;
405
406 if ((i == 0) || (i == -1))
407 {
408 err=get_last_socket_error();
409
410 #if defined(OPENSSL_SYS_WINDOWS) && 0 /* more microsoft stupidity? perhaps not? Ben 4/1/99 */
411 if ((i == -1) && (err == 0))
412 return(1);
413 #endif
414
415 return(BIO_dgram_non_fatal_error(err));
416 }
417 return(0);
418 }
419
BIO_dgram_non_fatal_error(int err)420 int BIO_dgram_non_fatal_error(int err)
421 {
422 switch (err)
423 {
424 #if defined(OPENSSL_SYS_WINDOWS)
425 # if defined(WSAEWOULDBLOCK)
426 case WSAEWOULDBLOCK:
427 # endif
428
429 # if 0 /* This appears to always be an error */
430 # if defined(WSAENOTCONN)
431 case WSAENOTCONN:
432 # endif
433 # endif
434 #endif
435
436 #ifdef EWOULDBLOCK
437 # ifdef WSAEWOULDBLOCK
438 # if WSAEWOULDBLOCK != EWOULDBLOCK
439 case EWOULDBLOCK:
440 # endif
441 # else
442 case EWOULDBLOCK:
443 # endif
444 #endif
445
446 #if defined(ENOTCONN)
447 case ENOTCONN:
448 #endif
449
450 #ifdef EINTR
451 case EINTR:
452 #endif
453
454 #ifdef EAGAIN
455 #if EWOULDBLOCK != EAGAIN
456 case EAGAIN:
457 # endif
458 #endif
459
460 #ifdef EPROTO
461 case EPROTO:
462 #endif
463
464 #ifdef EINPROGRESS
465 case EINPROGRESS:
466 #endif
467
468 #ifdef EALREADY
469 case EALREADY:
470 #endif
471
472 /* DF bit set, and packet larger than MTU */
473 #ifdef EMSGSIZE
474 case EMSGSIZE:
475 #endif
476
477 return(1);
478 /* break; */
479 default:
480 break;
481 }
482 return(0);
483 }
484 #endif
485