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[tripe] / tripe.c
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410c8acf 1/* -*-c-*-
2 *
d13e5724 3 * $Id: tripe.c,v 1.11 2003/05/17 11:02:03 mdw Exp $
410c8acf 4 *
5 * Main program
6 *
7 * (c) 2001 Straylight/Edgeware
8 */
9
10/*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of Trivial IP Encryption (TrIPE).
13 *
14 * TrIPE is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * TrIPE is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 *
24 * You should have received a copy of the GNU General Public License
25 * along with TrIPE; if not, write to the Free Software Foundation,
26 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 */
28
29/*----- Revision history --------------------------------------------------*
30 *
31 * $Log: tripe.c,v $
d13e5724 32 * Revision 1.11 2003/05/17 11:02:03 mdw
33 * Document the new `-b' option.
34 *
767b36e2 35 * Revision 1.10 2003/05/16 12:09:03 mdw
36 * Allow binding to a chosen address.
37 *
b303b584 38 * Revision 1.9 2003/04/15 14:11:09 mdw
39 * Rationalize the behaviour of the `-G' and `-U' options.
40 *
d360f042 41 * Revision 1.8 2002/01/13 17:28:29 mdw
42 * Don't turn tracing on if tracing is turned off (!).
43 *
c5a2ea9b 44 * Revision 1.7 2002/01/13 17:14:05 mdw
45 * Don't include the tracing option in the help if not compiled in.
46 *
2666d7dd 47 * Revision 1.6 2001/06/19 22:08:37 mdw
48 * Moved buffers to peer.c.
49 *
680bfcf4 50 * Revision 1.5 2001/02/16 21:43:12 mdw
51 * Provide a more helpful usage message.
52 *
37852359 53 * Revision 1.4 2001/02/16 21:41:31 mdw
54 * Add a new buffer.
55 *
efd6c9e3 56 * Revision 1.3 2001/02/04 17:10:40 mdw
57 * Remove a debugging @abort@ call.
58 *
e31c0b14 59 * Revision 1.2 2001/02/03 22:33:00 mdw
60 * Stuff more randomness into the pool in the interval timer.
61 *
410c8acf 62 * Revision 1.1 2001/02/03 20:26:37 mdw
63 * Initial checkin.
64 *
65 */
66
67/*----- Header files ------------------------------------------------------*/
68
69#include "tripe.h"
70
71/*----- Global variables --------------------------------------------------*/
72
73sel_state sel;
410c8acf 74
75/*----- Static variables --------------------------------------------------*/
76
77static sel_timer it;
78#define T_INTERVAL MIN(1)
79
80/*----- Main code ---------------------------------------------------------*/
81
82/* --- @interval@ --- *
83 *
84 * Arguments: @struct timeval *tv@ = time when called
85 * @void *v@ = boring pointer
86 *
87 * Returns: ---
88 *
89 * Use: Called periodically to do housekeeping tasks.
90 */
91
92void interval(struct timeval *tv, void *v)
93{
94 struct timeval tvv;
95 T( trace(T_PEER, "peer: interval timer"); )
37852359 96 rand_seed(RAND_GLOBAL, HASHSZ);
410c8acf 97 p_interval();
98 tvv = *tv;
99 tvv.tv_sec += T_INTERVAL;
100 sel_addtimer(&sel, &it, &tvv, interval, v);
101}
102
103/* --- @main@ --- *
104 *
105 * Arguments: @int argc@ = number of command line arguments
106 * @char *argv[]@ = vector of arguments
107 *
108 * Returns: Zero if OK, nonzero on error.
109 *
110 * Use: Main program. Provides a simple VPN.
111 */
112
113static void usage(FILE *fp)
114{
d13e5724 115 pquis(fp, "Usage: $ [-D] [-d dir] [-b addr] [-p port]\n\
116 [-U user] [-G group] [-a socket] [-T trace-opts]\n\
117 [-k priv-keyring] [-K pub-keyring] [-t key-tag]\n");
410c8acf 118}
119
120static void version(FILE *fp)
121{
122 pquis(fp, "$, version " VERSION "\n");
123}
124
125static void help(FILE *fp)
126{
127 version(fp);
128 fputc('\n', fp);
129 usage(fp);
130 fputs("\n\
131Options:\n\
132\n\
133-h, --help Display this help text.\n\
134-v, --version Display version number.\n\
135-u, --usage Display pointless usage message.\n\
136\n\
137-D, --daemon Run in the background.\n\
138-d, --directory=DIR Switch to directory DIR (default $TRIPEDIR).\n\
d13e5724 139-b, --bind-address=ADDR Bind UDP socket to this IP ADDR.\n\
410c8acf 140-p, --port=PORT Select UDP port to listen to.\n\
d13e5724 141-U, --setuid=USER Set uid to USER after initialization.\n\
142-G, --setgid=GROUP Set gid to GROUP after initialization.\n\
410c8acf 143-k, --priv-keyring=FILE Get private key from FILE.\n\
144-K, --pub-keyring=FILE Get public keys from FILE.\n\
145-t, --tag=KEYTAG Use private key labelled TAG.\n\
146-a, --admin-socket=FILE Use FILE as the adminstration socket.\n\
c5a2ea9b 147" T( "\
410c8acf 148-T, --trace=OPTIONS Turn on tracing options.\n\
c5a2ea9b 149" ) "\
410c8acf 150", fp);
151}
152
153int main(int argc, char *argv[])
154{
155 const char *kr_priv = "keyring", *kr_pub = "keyring.pub";
156 const char *tag_priv = "tripe-dh";
157 const char *csock = "tripesock";
158 const char *dir = "/var/lib/tripe";
159 const char *p;
160 unsigned port = 0;
767b36e2 161 struct in_addr baddr = { INADDR_ANY };
410c8acf 162 unsigned f = 0;
163 uid_t u = -1;
164 gid_t g = -1;
165
166#define f_bogus 1u
167#define f_daemon 2u
168
169 ego(argv[0]);
d360f042 170 T( trace_on(stderr, 0); )
410c8acf 171
172 if ((p = getenv("TRIPEDIR")) != 0)
173 dir = p;
174
175 for (;;) {
176 static const struct option opts[] = {
177 { "help", 0, 0, 'h' },
178 { "version", 0, 0, 'v' },
179 { "usage", 0, 0, 'u' },
180
181 { "daemon", 0, 0, 'D' },
182 { "uid", OPTF_ARGREQ, 0, 'U' },
183 { "setuid", OPTF_ARGREQ, 0, 'U' },
184 { "gid", OPTF_ARGREQ, 0, 'G' },
185 { "setgid", OPTF_ARGREQ, 0, 'G' },
767b36e2 186 { "bind-address", OPTF_ARGREQ, 0, 'b' },
410c8acf 187 { "port", OPTF_ARGREQ, 0, 'p' },
188 { "directory", OPTF_ARGREQ, 0, 'd' },
189 { "priv-keyring", OPTF_ARGREQ, 0, 'k' },
190 { "pub-keyring", OPTF_ARGREQ, 0, 'K' },
191 { "tag", OPTF_ARGREQ, 0, 't' },
192 { "admin-socket", OPTF_ARGREQ, 0, 'a' },
193#ifndef NTRACE
194 { "trace", OPTF_ARGREQ, 0, 'T' },
195#endif
196
197 { 0, 0, 0, 0 }
198 };
199
767b36e2 200 int i = mdwopt(argc, argv, "hvu DU:G: b:p:d:k:K:t:a:" T("T:"),
410c8acf 201 opts, 0, 0, 0);
202 if (i < 0)
203 break;
204 switch (i) {
205 case 'h':
206 help(stdout);
207 exit(0);
208 case 'v':
209 version(stdout);
210 exit(0);
211 case 'u':
212 usage(stdout);
213 exit(0);
214
215 case 'D':
216 f |= f_daemon;
217 break;
218 case 'U': {
b303b584 219 struct passwd *pw;
410c8acf 220 char *p;
221 unsigned long i = strtoul(optarg, &p, 0);
222 if (!*p)
b303b584 223 pw = getpwuid(i);
224 else
225 pw = getpwnam(optarg);
226 if (!pw)
227 die(EXIT_FAILURE, "user `%s' not found", optarg);
228 u = pw->pw_uid;
229 if (g == -1)
230 g = pw->pw_gid;
410c8acf 231 } break;
232 case 'G': {
b303b584 233 struct group *gr;
410c8acf 234 char *p;
235 unsigned long i = strtoul(optarg, &p, 0);
236 if (!*p)
b303b584 237 gr = getgrgid(i);
238 else
239 gr = getgrnam(optarg);
240 if (!gr)
241 die(EXIT_FAILURE, "group `%s' not found", optarg);
242 g = gr->gr_gid;
410c8acf 243 } break;
767b36e2 244
245 case 'b': {
246 struct hostent *h = gethostbyname(optarg);
247 if (!h)
248 die(EXIT_FAILURE, "unknown host name `%s'", optarg);
249 memcpy(&baddr, h->h_addr, sizeof(struct in_addr));
250 } break;
410c8acf 251 case 'p': {
252 char *p;
253 unsigned long i = strtoul(optarg, &p, 0);
254 if (*p) {
255 struct servent *s = getservbyname(optarg, "udp");
256 if (!s)
257 die(EXIT_FAILURE, "unknown service name `%s'", optarg);
258 i = ntohs(s->s_port);
259 }
260 if (i == 0 || i >= 65536)
261 die(EXIT_FAILURE, "bad port number %lu", i);
262 port = i;
263 } break;
264 case 'd':
265 dir = optarg;
266 break;
267 case 'k':
268 kr_priv = optarg;
269 break;
270 case 'K':
271 kr_pub = optarg;
272 break;
273 case 'a':
274 csock = optarg;
275 break;
276 case 't':
277 tag_priv = optarg;
278 break;
279#ifndef NTRACE
280 case 'T':
281 tr_flags = traceopt(tr_opts, optarg, tr_flags, 0);
282 trace_level(tr_flags);
283 break;
284#endif
285 default:
286 f |= f_bogus;
287 break;
288 }
289 }
290
291 if (optind < argc || (f & f_bogus)) {
292 usage(stderr);
293 exit(EXIT_FAILURE);
294 }
295
296 if (chdir(dir)) {
297 die(EXIT_FAILURE, "can't set current directory to `%s': %s",
298 dir, strerror(errno));
299 }
300
301 sel_init(&sel);
302 sig_init(&sel);
303 rand_noisesrc(RAND_GLOBAL, &noise_source);
304 rand_seed(RAND_GLOBAL, RMD160_HASHSZ);
305 signal(SIGPIPE, SIG_IGN);
306 tun_init();
767b36e2 307 p_init(baddr, port);
410c8acf 308 if (!(f & f_daemon))
309 a_create(STDIN_FILENO, STDOUT_FILENO);
b303b584 310 if (g != (gid_t)-1) {
311 if (setgid(g) || (getuid() == 0 && setgroups(1, &g))) {
410c8acf 312 die(EXIT_FAILURE, "couldn't setgid to %u: %s",
313 (unsigned)g, strerror(errno));
314 }
315 }
b303b584 316 if (u != (uid_t)-1) {
410c8acf 317 if (setuid(u)) {
318 die(EXIT_FAILURE, "couldn't setuid to %u: %s",
319 (unsigned)u, strerror(errno));
320 }
321 }
322 km_init(kr_priv, kr_pub, tag_priv);
323 a_init(csock);
324 if (f & f_daemon) {
37852359 325 if (u_daemon())
410c8acf 326 die(EXIT_FAILURE, "couldn't become a daemon: %s", strerror(errno));
327 a_daemon();
328 }
329
330 {
331 struct timeval tv;
332 tv.tv_sec = time(0) + T_INTERVAL;
333 tv.tv_usec = 0;
334 sel_addtimer(&sel, &it, &tv, interval, 0);
335 }
336
337 {
338 int selerr = 0;
339 for (;;) {
340 if (!sel_select(&sel))
341 selerr = 0;
342 else if (errno != EINTR && errno != EAGAIN) {
343 a_warn("select failed: %s", strerror(errno));
410c8acf 344 selerr++;
345 if (selerr > 8) {
346 a_warn("too many select errors: bailing out");
347 a_quit();
348 }
349 }
350 }
351 }
352
353 return (0);
354}
355
356/*----- That's all, folks -------------------------------------------------*/