1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 1997 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/param.h>
30
31 #include <sys/socket.h>
32 #include <netinet/in.h>
33 #include <sys/un.h>
34
35 #include <errno.h>
36 #include <stdarg.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <sys/stat.h>
40 #include <termios.h>
41 #include <unistd.h>
42
43 #include "log.h"
44 #include "descriptor.h"
45 #include "server.h"
46 #include "prompt.h"
47 #include "ncpaddr.h"
48 #include "probe.h"
49
50 static int
server_UpdateSet(struct fdescriptor * d,fd_set * r,fd_set * w,fd_set * e,int * n)51 server_UpdateSet(struct fdescriptor *d, fd_set *r, fd_set *w, fd_set *e, int *n)
52 {
53 struct server *s = descriptor2server(d);
54 struct prompt *p;
55 int sets;
56
57 sets = 0;
58 if (r && s->fd >= 0) {
59 if (*n < s->fd + 1)
60 *n = s->fd + 1;
61 FD_SET(s->fd, r);
62 log_Printf(LogTIMER, "server: fdset(r) %d\n", s->fd);
63 sets++;
64 }
65
66 for (p = log_PromptList(); p; p = p->next)
67 sets += descriptor_UpdateSet(&p->desc, r, w, e, n);
68
69 return sets;
70 }
71
72 static int
server_IsSet(struct fdescriptor * d,const fd_set * fdset)73 server_IsSet(struct fdescriptor *d, const fd_set *fdset)
74 {
75 struct server *s = descriptor2server(d);
76 struct prompt *p;
77
78 if (s->fd >= 0 && FD_ISSET(s->fd, fdset))
79 return 1;
80
81 for (p = log_PromptList(); p; p = p->next)
82 if (descriptor_IsSet(&p->desc, fdset))
83 return 1;
84
85 return 0;
86 }
87
88 static void
server_Read(struct fdescriptor * d,struct bundle * bundle,const fd_set * fdset)89 server_Read(struct fdescriptor *d, struct bundle *bundle, const fd_set *fdset)
90 {
91 struct server *s = descriptor2server(d);
92 struct sockaddr_storage ss;
93 struct sockaddr *sa = (struct sockaddr *)&ss;
94 struct sockaddr_in *sin = (struct sockaddr_in *)&ss;
95 #ifndef NOINET6
96 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&ss;
97 #endif
98 int ssize = sizeof ss, wfd;
99 struct prompt *p;
100 struct ncpaddr addr;
101
102 if (s->fd >= 0 && FD_ISSET(s->fd, fdset)) {
103 wfd = accept(s->fd, sa, &ssize);
104 if (wfd < 0)
105 log_Printf(LogERROR, "server_Read: accept(): %s\n", strerror(errno));
106 else if (sa->sa_len == 0) {
107 close(wfd);
108 wfd = -1;
109 }
110 } else
111 wfd = -1;
112
113 if (wfd >= 0)
114 switch (sa->sa_family) {
115 case AF_LOCAL:
116 log_Printf(LogPHASE, "Connected to local client.\n");
117 break;
118
119 case AF_INET:
120 ncpaddr_setsa(&addr, sa);
121 if (ntohs(sin->sin_port) < 1024) {
122 log_Printf(LogALERT, "Rejected client connection from %s:%u"
123 "(invalid port number) !\n",
124 ncpaddr_ntoa(&addr), ntohs(sin->sin_port));
125 close(wfd);
126 wfd = -1;
127 break;
128 }
129 log_Printf(LogPHASE, "Connected to client from %s:%u\n",
130 ncpaddr_ntoa(&addr), ntohs(sin->sin_port));
131 break;
132
133 #ifndef NOINET6
134 case AF_INET6:
135 ncpaddr_setsa(&addr, sa);
136 if (ntohs(sin6->sin6_port) < 1024) {
137 log_Printf(LogALERT, "Rejected client connection from %s:%u"
138 "(invalid port number) !\n",
139 ncpaddr_ntoa(&addr), ntohs(sin6->sin6_port));
140 close(wfd);
141 wfd = -1;
142 break;
143 }
144 log_Printf(LogPHASE, "Connected to client from %s:%u\n",
145 ncpaddr_ntoa(&addr), ntohs(sin6->sin6_port));
146 break;
147 #endif
148
149 default:
150 write(wfd, "Unrecognised access !\n", 22);
151 close(wfd);
152 wfd = -1;
153 break;
154 }
155
156 if (wfd >= 0) {
157 if ((p = prompt_Create(s, bundle, wfd)) == NULL) {
158 write(wfd, "Connection refused.\n", 20);
159 close(wfd);
160 } else {
161 switch (sa->sa_family) {
162 case AF_LOCAL:
163 p->src.type = "local";
164 strncpy(p->src.from, s->cfg.sockname, sizeof p->src.from - 1);
165 p->src.from[sizeof p->src.from - 1] = '\0';
166 break;
167 case AF_INET:
168 p->src.type = "ip";
169 snprintf(p->src.from, sizeof p->src.from, "%s:%u",
170 ncpaddr_ntoa(&addr), ntohs(sin->sin_port));
171 break;
172 #ifndef NOINET6
173 case AF_INET6:
174 p->src.type = "ip6";
175 snprintf(p->src.from, sizeof p->src.from, "%s:%u",
176 ncpaddr_ntoa(&addr), ntohs(sin6->sin6_port));
177 break;
178 #endif
179 }
180 prompt_TtyCommandMode(p);
181 prompt_Required(p);
182 }
183 }
184
185 log_PromptListChanged = 0;
186 for (p = log_PromptList(); p; p = p->next)
187 if (descriptor_IsSet(&p->desc, fdset)) {
188 descriptor_Read(&p->desc, bundle, fdset);
189 if (log_PromptListChanged)
190 break;
191 }
192 }
193
194 static int
server_Write(struct fdescriptor * d __unused,struct bundle * bundle __unused,const fd_set * fdset __unused)195 server_Write(struct fdescriptor *d __unused, struct bundle *bundle __unused,
196 const fd_set *fdset __unused)
197 {
198 /* We never want to write here ! */
199 log_Printf(LogALERT, "server_Write: Internal error: Bad call !\n");
200 return 0;
201 }
202
203 struct server server = {
204 {
205 SERVER_DESCRIPTOR,
206 server_UpdateSet,
207 server_IsSet,
208 server_Read,
209 server_Write
210 },
211 -1,
212 { "", "", 0, 0 }
213 };
214
215 enum server_stat
server_Reopen(struct bundle * bundle)216 server_Reopen(struct bundle *bundle)
217 {
218 char name[sizeof server.cfg.sockname];
219 struct stat st;
220 u_short port;
221 mode_t mask;
222 enum server_stat ret;
223
224 if (server.cfg.sockname[0] != '\0') {
225 strcpy(name, server.cfg.sockname);
226 mask = server.cfg.mask;
227 server_Close(bundle);
228 if (server.cfg.sockname[0] != '\0' && stat(server.cfg.sockname, &st) == 0)
229 if (!(st.st_mode & S_IFSOCK) || unlink(server.cfg.sockname) != 0)
230 return SERVER_FAILED;
231 ret = server_LocalOpen(bundle, name, mask);
232 } else if (server.cfg.port != 0) {
233 port = server.cfg.port;
234 server_Close(bundle);
235 ret = server_TcpOpen(bundle, port);
236 } else
237 ret = SERVER_UNSET;
238
239 return ret;
240 }
241
242 enum server_stat
server_LocalOpen(struct bundle * bundle,const char * name,mode_t mask)243 server_LocalOpen(struct bundle *bundle, const char *name, mode_t mask)
244 {
245 struct sockaddr_un ifsun;
246 mode_t oldmask;
247 int s;
248
249 oldmask = (mode_t)-1; /* Silence compiler */
250
251 if (server.cfg.sockname[0] != '\0' && !strcmp(server.cfg.sockname, name))
252 server_Close(bundle);
253
254 memset(&ifsun, '\0', sizeof ifsun);
255 ifsun.sun_len = strlen(name);
256 if (ifsun.sun_len > sizeof ifsun.sun_path - 1) {
257 log_Printf(LogERROR, "Local: %s: Path too long\n", name);
258 return SERVER_INVALID;
259 }
260 ifsun.sun_family = AF_LOCAL;
261 strcpy(ifsun.sun_path, name);
262
263 s = socket(PF_LOCAL, SOCK_STREAM, 0);
264 if (s < 0) {
265 log_Printf(LogERROR, "Local: socket: %s\n", strerror(errno));
266 goto failed;
267 }
268 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &s, sizeof s);
269 if (mask != (mode_t)-1)
270 oldmask = umask(mask);
271 if (bind(s, (struct sockaddr *)&ifsun, sizeof ifsun) < 0) {
272 if (mask != (mode_t)-1)
273 umask(oldmask);
274 log_Printf(LogWARN, "Local: bind: %s\n", strerror(errno));
275 close(s);
276 goto failed;
277 }
278 if (mask != (mode_t)-1)
279 umask(oldmask);
280 if (listen(s, 5) != 0) {
281 log_Printf(LogERROR, "Local: Unable to listen to socket -"
282 " BUNDLE overload?\n");
283 close(s);
284 unlink(name);
285 goto failed;
286 }
287 server_Close(bundle);
288 server.fd = s;
289 server.cfg.port = 0;
290 strncpy(server.cfg.sockname, ifsun.sun_path, sizeof server.cfg.sockname - 1);
291 server.cfg.sockname[sizeof server.cfg.sockname - 1] = '\0';
292 server.cfg.mask = mask;
293 log_Printf(LogPHASE, "Listening at local socket %s.\n", name);
294
295 return SERVER_OK;
296
297 failed:
298 if (server.fd == -1) {
299 server.fd = -1;
300 server.cfg.port = 0;
301 strncpy(server.cfg.sockname, ifsun.sun_path,
302 sizeof server.cfg.sockname - 1);
303 server.cfg.sockname[sizeof server.cfg.sockname - 1] = '\0';
304 server.cfg.mask = mask;
305 }
306 return SERVER_FAILED;
307 }
308
309 enum server_stat
server_TcpOpen(struct bundle * bundle,u_short port)310 server_TcpOpen(struct bundle *bundle, u_short port)
311 {
312 struct sockaddr_storage ss;
313 struct sockaddr_in *sin = (struct sockaddr_in *)&ss;
314 #ifndef NOINET6
315 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&ss;
316 #endif
317 int s, sz;
318
319 if (server.cfg.port == port)
320 server_Close(bundle);
321
322 if (port == 0)
323 return SERVER_INVALID;
324
325 memset(&ss, '\0', sizeof ss);
326 #ifndef NOINET6
327 if (probe.ipv6_available) {
328 sin6->sin6_family = AF_INET6;
329 sin6->sin6_port = htons(port);
330 sin6->sin6_len = (u_int8_t)sizeof ss;
331 sz = sizeof *sin6;
332 s = socket(PF_INET6, SOCK_STREAM, 0);
333 } else
334 #endif
335 {
336 sin->sin_family = AF_INET;
337 sin->sin_port = htons(port);
338 sin->sin_len = (u_int8_t)sizeof ss;
339 sin->sin_addr.s_addr = INADDR_ANY;
340 sz = sizeof *sin;
341 s = socket(PF_INET, SOCK_STREAM, 0);
342 }
343
344 if (s < 0) {
345 log_Printf(LogERROR, "Tcp: socket: %s\n", strerror(errno));
346 goto failed;
347 }
348
349 #ifndef NOINET6
350 if (probe.ipv6_available) {
351 int off = 0;
352 setsockopt(s, IPPROTO_IPV6, IPV6_V6ONLY, (char *)&off, sizeof(off));
353 }
354 #endif
355
356 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &s, sizeof s);
357 if (bind(s, (struct sockaddr *)&ss, sz) < 0) {
358 log_Printf(LogWARN, "Tcp: bind: %s\n", strerror(errno));
359 close(s);
360 goto failed;
361 }
362 if (listen(s, 5) != 0) {
363 log_Printf(LogERROR, "Tcp: Unable to listen to socket: %s\n",
364 strerror(errno));
365 close(s);
366 goto failed;
367 }
368 server_Close(bundle);
369 server.fd = s;
370 server.cfg.port = port;
371 *server.cfg.sockname = '\0';
372 server.cfg.mask = 0;
373 log_Printf(LogPHASE, "Listening at port %d.\n", port);
374 return SERVER_OK;
375
376 failed:
377 if (server.fd == -1) {
378 server.fd = -1;
379 server.cfg.port = port;
380 *server.cfg.sockname = '\0';
381 server.cfg.mask = 0;
382 }
383 return SERVER_FAILED;
384 }
385
386 int
server_Close(struct bundle * bundle __unused)387 server_Close(struct bundle *bundle __unused)
388 {
389 if (server.fd >= 0) {
390 if (*server.cfg.sockname != '\0') {
391 struct sockaddr_un un;
392 int sz = sizeof un;
393
394 if (getsockname(server.fd, (struct sockaddr *)&un, &sz) == 0 &&
395 un.sun_family == AF_LOCAL && sz == sizeof un)
396 unlink(un.sun_path);
397 }
398 close(server.fd);
399 server.fd = -1;
400 /* Drop associated prompts */
401 log_DestroyPrompts(&server);
402
403 return 1;
404 }
405
406 return 0;
407 }
408
409 int
server_Clear(struct bundle * bundle)410 server_Clear(struct bundle *bundle)
411 {
412 int ret;
413
414 ret = server_Close(bundle);
415
416 server.fd = -1;
417 server.cfg.port = 0;
418 *server.cfg.sockname = '\0';
419 server.cfg.mask = 0;
420
421 return ret;
422 }
423