1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include <sys/types.h>
30 #include <sys/socket.h>
31 #include <netinet/in.h>
32 #include <arpa/inet.h>
33 #include <netdb.h>
34
35 #include <errno.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <sysexits.h>
40 #include <sys/stat.h>
41 #include <sys/uio.h>
42 #include <termios.h>
43 #include <unistd.h>
44
45 #include "layer.h"
46 #include "defs.h"
47 #include "mbuf.h"
48 #include "log.h"
49 #include "timer.h"
50 #include "lqr.h"
51 #include "hdlc.h"
52 #include "throughput.h"
53 #include "fsm.h"
54 #include "lcp.h"
55 #include "ccp.h"
56 #include "link.h"
57 #include "async.h"
58 #include "descriptor.h"
59 #include "physical.h"
60 #include "main.h"
61 #include "udp.h"
62
63
64 #define UDP_CONNECTED 1
65 #define UDP_UNCONNECTED 2
66 #define UDP_MAYBEUNCONNECTED 3
67
68 struct udpdevice {
69 struct device dev; /* What struct physical knows about */
70 struct sockaddr_in sock; /* peer address */
71 unsigned connected : 2; /* Have we connect()d ? */
72 };
73
74 #define device2udp(d) ((d)->type == UDP_DEVICE ? (struct udpdevice *)d : NULL)
75
76 unsigned
udp_DeviceSize(void)77 udp_DeviceSize(void)
78 {
79 return sizeof(struct udpdevice);
80 }
81
82 static ssize_t
udp_Sendto(struct physical * p,const void * v,size_t n)83 udp_Sendto(struct physical *p, const void *v, size_t n)
84 {
85 struct udpdevice *dev = device2udp(p->handler);
86 int ret;
87
88 switch (dev->connected) {
89 case UDP_CONNECTED:
90 ret = write(p->fd, v, n);
91 break;
92
93 case UDP_UNCONNECTED:
94 default:
95 ret = sendto(p->fd, v, n, 0, (struct sockaddr *)&dev->sock,
96 sizeof dev->sock);
97 break;
98 }
99 if (dev->connected == UDP_MAYBEUNCONNECTED) {
100 if (ret == -1 && errno == EISCONN) {
101 dev->connected = UDP_CONNECTED;
102 ret = write(p->fd, v, n);
103 } else
104 dev->connected = UDP_UNCONNECTED;
105 }
106
107 return ret;
108 }
109
110 static ssize_t
udp_Recvfrom(struct physical * p,void * v,size_t n)111 udp_Recvfrom(struct physical *p, void *v, size_t n)
112 {
113 struct udpdevice *dev = device2udp(p->handler);
114 int sz, ret;
115
116 if (dev->connected == UDP_CONNECTED)
117 return read(p->fd, v, n);
118
119 sz = sizeof dev->sock;
120 ret = recvfrom(p->fd, v, n, 0, (struct sockaddr *)&dev->sock, &sz);
121
122 if (*p->name.full == '\0') {
123 snprintf(p->name.full, sizeof p->name.full, "%s:%d/udp",
124 inet_ntoa(dev->sock.sin_addr), ntohs(dev->sock.sin_port));
125 p->name.base = p->name.full;
126 }
127
128 return ret;
129 }
130
131 static void
udp_Free(struct physical * p)132 udp_Free(struct physical *p)
133 {
134 struct udpdevice *dev = device2udp(p->handler);
135
136 free(dev);
137 }
138
139 static void
udp_device2iov(struct device * d,struct iovec * iov,int * niov,int maxiov __unused,int * auxfd __unused,int * nauxfd __unused)140 udp_device2iov(struct device *d, struct iovec *iov, int *niov,
141 int maxiov __unused, int *auxfd __unused, int *nauxfd __unused)
142 {
143 int sz = physical_MaxDeviceSize();
144
145 iov[*niov].iov_base = realloc(d, sz);
146 if (iov[*niov].iov_base == NULL) {
147 log_Printf(LogALERT, "Failed to allocate memory: %d\n", sz);
148 AbortProgram(EX_OSERR);
149 }
150 iov[*niov].iov_len = sz;
151 (*niov)++;
152 }
153
154 static const struct device baseudpdevice = {
155 UDP_DEVICE,
156 "udp",
157 0,
158 { CD_NOTREQUIRED, 0 },
159 NULL,
160 NULL,
161 NULL,
162 NULL,
163 NULL,
164 NULL,
165 NULL,
166 udp_Free,
167 udp_Recvfrom,
168 udp_Sendto,
169 udp_device2iov,
170 NULL,
171 NULL,
172 NULL
173 };
174
175 struct device *
udp_iov2device(int type,struct physical * p,struct iovec * iov,int * niov,int maxiov __unused,int * auxfd __unused,int * nauxfd __unused)176 udp_iov2device(int type, struct physical *p, struct iovec *iov, int *niov,
177 int maxiov __unused, int *auxfd __unused, int *nauxfd __unused)
178 {
179 if (type == UDP_DEVICE) {
180 struct udpdevice *dev = (struct udpdevice *)iov[(*niov)++].iov_base;
181
182 dev = realloc(dev, sizeof *dev); /* Reduce to the correct size */
183 if (dev == NULL) {
184 log_Printf(LogALERT, "Failed to allocate memory: %d\n",
185 (int)(sizeof *dev));
186 AbortProgram(EX_OSERR);
187 }
188
189 /* Refresh function pointers etc */
190 memcpy(&dev->dev, &baseudpdevice, sizeof dev->dev);
191
192 physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNC);
193 return &dev->dev;
194 }
195
196 return NULL;
197 }
198
199 static struct udpdevice *
udp_CreateDevice(struct physical * p,char * host,char * port)200 udp_CreateDevice(struct physical *p, char *host, char *port)
201 {
202 struct udpdevice *dev;
203 struct servent *sp;
204
205 if ((dev = malloc(sizeof *dev)) == NULL) {
206 log_Printf(LogWARN, "%s: Cannot allocate a udp device: %s\n",
207 p->link.name, strerror(errno));
208 return NULL;
209 }
210
211 dev->sock.sin_family = AF_INET;
212 dev->sock.sin_addr = GetIpAddr(host);
213 if (dev->sock.sin_addr.s_addr == INADDR_NONE) {
214 log_Printf(LogWARN, "%s: %s: unknown host\n", p->link.name, host);
215 free(dev);
216 return NULL;
217 }
218 dev->sock.sin_port = htons(atoi(port));
219 if (dev->sock.sin_port == 0) {
220 sp = getservbyname(port, "udp");
221 if (sp)
222 dev->sock.sin_port = sp->s_port;
223 else {
224 log_Printf(LogWARN, "%s: %s: unknown service\n", p->link.name, port);
225 free(dev);
226 return NULL;
227 }
228 }
229
230 log_Printf(LogPHASE, "%s: Connecting to %s:%s/udp\n", p->link.name,
231 host, port);
232
233 p->fd = socket(PF_INET, SOCK_DGRAM, 0);
234 if (p->fd >= 0) {
235 log_Printf(LogDEBUG, "%s: Opened udp socket %s\n", p->link.name,
236 p->name.full);
237 if (connect(p->fd, (struct sockaddr *)&dev->sock, sizeof dev->sock) == 0) {
238 dev->connected = UDP_CONNECTED;
239 return dev;
240 } else
241 log_Printf(LogWARN, "%s: connect: %s\n", p->name.full, strerror(errno));
242 } else
243 log_Printf(LogWARN, "%s: socket: %s\n", p->name.full, strerror(errno));
244
245 close(p->fd);
246 p->fd = -1;
247 free(dev);
248
249 return NULL;
250 }
251
252 struct device *
udp_Create(struct physical * p)253 udp_Create(struct physical *p)
254 {
255 char *cp, *host, *port, *svc;
256 struct udpdevice *dev;
257
258 dev = NULL;
259 if (p->fd < 0) {
260 if ((cp = strchr(p->name.full, ':')) != NULL && !strchr(cp + 1, ':')) {
261 *cp = '\0';
262 host = p->name.full;
263 port = cp + 1;
264 svc = strchr(port, '/');
265 if (svc && strcasecmp(svc, "/udp")) {
266 *cp = ':';
267 return NULL;
268 }
269 if (svc) {
270 p->fd--; /* We own the device but maybe can't use it - change fd */
271 *svc = '\0';
272 }
273
274 if (*host && *port)
275 dev = udp_CreateDevice(p, host, port);
276
277 *cp = ':';
278 if (svc)
279 *svc = '/';
280 }
281 } else {
282 /* See if we're a connected udp socket */
283 struct stat st;
284
285 if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
286 int type, sz;
287
288 sz = sizeof type;
289 if (getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz) == -1) {
290 log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
291 close(p->fd);
292 p->fd = -1;
293 return NULL;
294 }
295
296 if (sz == sizeof type && type == SOCK_DGRAM) {
297 struct sockaddr_in sock;
298 struct sockaddr *sockp = (struct sockaddr *)&sock;
299
300 if ((dev = malloc(sizeof *dev)) == NULL) {
301 log_Printf(LogWARN, "%s: Cannot allocate a udp device: %s\n",
302 p->link.name, strerror(errno));
303 return NULL;
304 }
305
306 if (getpeername(p->fd, sockp, &sz) == 0) {
307 log_Printf(LogPHASE, "%s: Link is a connected udp socket\n",
308 p->link.name);
309 dev->connected = UDP_CONNECTED;
310 } else {
311 log_Printf(LogPHASE, "%s: Link is a disconnected udp socket\n",
312 p->link.name);
313
314 dev->connected = UDP_MAYBEUNCONNECTED;
315
316 if (p->link.lcp.cfg.openmode != OPEN_PASSIVE) {
317 log_Printf(LogPHASE, "%s: Changing openmode to PASSIVE\n",
318 p->link.name);
319 p->link.lcp.cfg.openmode = OPEN_PASSIVE;
320 }
321 }
322 }
323 }
324 }
325
326 if (dev) {
327 memcpy(&dev->dev, &baseudpdevice, sizeof dev->dev);
328 physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNC);
329 if (p->cfg.cd.necessity != CD_DEFAULT)
330 log_Printf(LogWARN, "Carrier settings ignored\n");
331 return &dev->dev;
332 }
333
334 return NULL;
335 }
336