Commit | Line | Data |
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9da480be MW |
1 | /* -*-c-*- |
2 | * | |
3 | * Main daemon | |
4 | * | |
5 | * (c) 2012 Straylight/Edgeware | |
6 | */ | |
7 | ||
8 | /*----- Licensing notice --------------------------------------------------* | |
9 | * | |
10 | * This file is part of Yet Another Ident Daemon (YAID). | |
11 | * | |
12 | * YAID is free software; you can redistribute it and/or modify | |
13 | * it under the terms of the GNU General Public License as published by | |
14 | * the Free Software Foundation; either version 2 of the License, or | |
15 | * (at your option) any later version. | |
16 | * | |
17 | * YAID is distributed in the hope that it will be useful, | |
18 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
19 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
20 | * GNU General Public License for more details. | |
21 | * | |
22 | * You should have received a copy of the GNU General Public License | |
23 | * along with YAID; if not, write to the Free Software Foundation, | |
24 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
25 | */ | |
26 | ||
27 | /*----- Header files ------------------------------------------------------*/ | |
28 | ||
29 | #include "yaid.h" | |
30 | ||
31 | /*----- Data structures ---------------------------------------------------*/ | |
32 | ||
c3794524 MW |
33 | /* A write buffer is the gadget which keeps track of our output and writes |
34 | * portions of it out as and when connections are ready for it. | |
35 | */ | |
9da480be MW |
36 | #define WRBUFSZ 1024 |
37 | struct writebuf { | |
c3794524 MW |
38 | size_t o; /* Offset of remaining data */ |
39 | size_t n; /* Length of remaining data */ | |
40 | sel_file wr; /* Write selector */ | |
41 | void (*func)(int /*err*/, void *); /* Function to call on completion */ | |
42 | void *p; /* Context for `func' */ | |
43 | unsigned char buf[WRBUFSZ]; /* Output buffer */ | |
9da480be MW |
44 | }; |
45 | ||
c3794524 MW |
46 | /* Structure for a listening socket. There's one of these for each address |
47 | * family we're looking after. | |
48 | */ | |
49 | struct listen { | |
50 | const struct addrops *ao; /* Address family operations */ | |
51 | sel_file f; /* Watch for incoming connections */ | |
9da480be MW |
52 | }; |
53 | ||
c3794524 | 54 | /* The main structure for a client. */ |
9da480be | 55 | struct client { |
c3794524 MW |
56 | int fd; /* The connection to the client */ |
57 | selbuf b; /* Accumulate lines of input */ | |
223e3e2b | 58 | union addr raddr; /* Remote address */ |
c3794524 | 59 | struct query q; /* The clients query and our reply */ |
4f8fdcc1 | 60 | struct sel_timer t; /* Timeout for idle or doomed conn */ |
c3794524 MW |
61 | struct listen *l; /* Back to the listener (and ops) */ |
62 | struct writebuf wb; /* Write buffer for our reply */ | |
63 | struct proxy *px; /* Proxy if conn goes via NAT */ | |
64 | }; | |
65 | ||
66 | /* A proxy connection. */ | |
67 | struct proxy { | |
68 | int fd; /* Connection; -1 if in progress */ | |
69 | struct client *c; /* Back to the client */ | |
70 | conn cn; /* Nonblocking connection */ | |
71 | selbuf b; /* Accumulate the response line */ | |
72 | struct writebuf wb; /* Write buffer for query */ | |
73 | char nat[ADDRLEN]; /* Server address, as text */ | |
9da480be MW |
74 | }; |
75 | ||
76 | /*----- Static variables --------------------------------------------------*/ | |
77 | ||
c3794524 | 78 | static sel_state sel; /* I/O multiplexer state */ |
9da480be | 79 | |
74716d82 MW |
80 | static const char *pidfile = 0; /* Where to write daemon's pid */ |
81 | ||
82 | static const char *policyfile = POLICYFILE; /* Filename for global policy */ | |
c3794524 MW |
83 | static const struct policy default_policy = POLICY_INIT(A_NAME); |
84 | static policy_v policy = DA_INIT; /* Vector of global policy rules */ | |
85 | static fwatch polfw; /* Watch policy file for changes */ | |
9da480be | 86 | |
c3794524 MW |
87 | static unsigned char tokenbuf[4096]; /* Random-ish data for tokens */ |
88 | static size_t tokenptr = sizeof(tokenbuf); /* Current read position */ | |
89 | static int randfd; /* File descriptor for random data */ | |
9da480be | 90 | |
74716d82 MW |
91 | static unsigned flags = 0; /* Various interesting flags */ |
92 | #define F_SYSLOG 1u /* Use syslog for logging */ | |
93 | #define F_RUNNING 2u /* Running properly now */ | |
94 | ||
c3794524 | 95 | /*----- Ident protocol parsing --------------------------------------------*/ |
9da480be | 96 | |
c3794524 MW |
97 | /* Advance *PP over whitespace characters. */ |
98 | static void skipws(const char **pp) | |
99 | { while (isspace((unsigned char )**pp)) (*pp)++; } | |
100 | ||
101 | /* Copy a token of no more than N bytes starting at *PP into Q, advancing *PP | |
102 | * over it. | |
103 | */ | |
104 | static int idtoken(const char **pp, char *q, size_t n) | |
9da480be | 105 | { |
c3794524 | 106 | const char *p = *pp; |
9da480be | 107 | |
c3794524 MW |
108 | skipws(&p); |
109 | n--; | |
110 | for (;;) { | |
111 | if (*p == ':' || *p <= 32 || *p >= 127) break; | |
112 | if (!n) return (-1); | |
113 | *q++ = *p++; | |
114 | n--; | |
9da480be | 115 | } |
c3794524 MW |
116 | *q++ = 0; |
117 | *pp = p; | |
118 | return (0); | |
119 | } | |
120 | ||
121 | /* Read an unsigned decimal number from *PP, and store it in *II. Check that | |
122 | * it's between MIN and MAX, and advance *PP over it. Return zero for | |
123 | * success, or nonzero if something goes wrong. | |
124 | */ | |
125 | static int unum(const char **pp, unsigned *ii, unsigned min, unsigned max) | |
126 | { | |
127 | char *q; | |
128 | unsigned long i; | |
129 | int e; | |
130 | ||
131 | skipws(pp); | |
132 | if (!isdigit((unsigned char)**pp)) return (-1); | |
133 | e = errno; errno = 0; | |
134 | i = strtoul(*pp, &q, 10); | |
135 | if (errno) return (-1); | |
136 | *pp = q; | |
137 | errno = e; | |
138 | if (i < min || i > max) return (-1); | |
139 | *ii = i; | |
140 | return (0); | |
9da480be MW |
141 | } |
142 | ||
c3794524 MW |
143 | /*----- Asynchronous writing ----------------------------------------------*/ |
144 | ||
145 | /* Callback for actually writing stuff from a `writebuf'. */ | |
9da480be MW |
146 | static void write_out(int fd, unsigned mode, void *p) |
147 | { | |
148 | ssize_t n; | |
149 | struct writebuf *wb = p; | |
150 | ||
c3794524 | 151 | /* Try to write something. */ |
9da480be MW |
152 | if ((n = write(fd, wb->buf + wb->o, wb->n)) < 0) { |
153 | if (errno == EAGAIN || errno == EWOULDBLOCK) return; | |
154 | wb->n = 0; | |
155 | sel_rmfile(&wb->wr); | |
156 | wb->func(errno, wb->p); | |
157 | } | |
158 | wb->o += n; | |
159 | wb->n -= n; | |
c3794524 MW |
160 | |
161 | /* If there's nothing left then restore the buffer to its empty state. */ | |
9da480be MW |
162 | if (!wb->n) { |
163 | wb->o = 0; | |
164 | sel_rmfile(&wb->wr); | |
165 | wb->func(0, wb->p); | |
166 | } | |
167 | } | |
168 | ||
c3794524 | 169 | /* Queue N bytes starting at P to be written. */ |
9da480be MW |
170 | static int queue_write(struct writebuf *wb, const void *p, size_t n) |
171 | { | |
c3794524 | 172 | /* Maybe there's nothing to actually do. */ |
9da480be | 173 | if (!n) return (0); |
c3794524 MW |
174 | |
175 | /* Make sure it'll fit. */ | |
9da480be | 176 | if (wb->n - wb->o + n > WRBUFSZ) return (-1); |
c3794524 MW |
177 | |
178 | /* If there's anything there already, then make sure it's at the start of | |
179 | * the available space. | |
180 | */ | |
9da480be MW |
181 | if (wb->o) { |
182 | memmove(wb->buf, wb->buf + wb->o, wb->n); | |
183 | wb->o = 0; | |
184 | } | |
c3794524 MW |
185 | |
186 | /* If there's nothing currently there, then we're not requesting write | |
187 | * notifications, so set that up, and force an initial wake-up. | |
188 | */ | |
9da480be MW |
189 | if (!wb->n) { |
190 | sel_addfile(&wb->wr); | |
191 | sel_force(&wb->wr); | |
192 | } | |
c3794524 MW |
193 | |
194 | /* Copy the new material over. */ | |
195 | memcpy(wb->buf + wb->n, p, n); | |
9da480be | 196 | wb->n += n; |
c3794524 MW |
197 | |
198 | /* Done. */ | |
9da480be MW |
199 | return (0); |
200 | } | |
201 | ||
c3794524 | 202 | /* Release resources allocated to WB. */ |
9da480be MW |
203 | static void free_writebuf(struct writebuf *wb) |
204 | { if (wb->n) sel_rmfile(&wb->wr); } | |
205 | ||
c3794524 MW |
206 | /* Initialize a writebuf in *WB, writing to file descriptor FD. On |
207 | * completion, call FUNC, passing it P and an error indicator: either 0 for | |
208 | * success or an `errno' value on failure. | |
209 | */ | |
9da480be MW |
210 | static void init_writebuf(struct writebuf *wb, |
211 | int fd, void (*func)(int, void *), void *p) | |
212 | { | |
213 | sel_initfile(&sel, &wb->wr, fd, SEL_WRITE, write_out, wb); | |
214 | wb->func = func; | |
215 | wb->p = p; | |
216 | wb->n = wb->o = 0; | |
217 | } | |
218 | ||
c3794524 | 219 | /*----- General utilities -------------------------------------------------*/ |
9da480be | 220 | |
c3794524 MW |
221 | /* Format and log MSG somewhere sensible, at the syslog(3) priority PRIO. |
222 | * Prefix it with a description of the query Q, if non-null. | |
223 | */ | |
224 | void logmsg(const struct query *q, int prio, const char *msg, ...) | |
9da480be | 225 | { |
c3794524 MW |
226 | va_list ap; |
227 | dstr d = DSTR_INIT; | |
74716d82 MW |
228 | time_t t; |
229 | struct tm *tm; | |
230 | char buf[64]; | |
c3794524 MW |
231 | |
232 | va_start(ap, msg); | |
233 | if (q) { | |
234 | dputsock(&d, q->ao, &q->s[L]); | |
235 | dstr_puts(&d, " <-> "); | |
236 | dputsock(&d, q->ao, &q->s[R]); | |
237 | dstr_puts(&d, ": "); | |
238 | } | |
239 | dstr_vputf(&d, msg, &ap); | |
240 | va_end(ap); | |
74716d82 MW |
241 | |
242 | if (!(flags & F_RUNNING)) | |
243 | moan("%s", d.buf); | |
244 | else if (flags & F_SYSLOG) | |
245 | syslog(prio, "%s", d.buf); | |
246 | else { | |
247 | t = time(0); | |
248 | tm = localtime(&t); | |
249 | strftime(buf, sizeof(buf), "%Y-%m-%d %H:%M:%S %z", tm); | |
250 | fprintf(stderr, "%s %s: %s\n", buf, QUIS, d.buf); | |
251 | } | |
252 | ||
c3794524 | 253 | dstr_destroy(&d); |
9da480be MW |
254 | } |
255 | ||
c3794524 MW |
256 | /* Fix up a socket FD so that it won't bite us. Returns zero on success, or |
257 | * nonzero on error. | |
258 | */ | |
95df134c MW |
259 | static int fix_up_socket(int fd, const char *what) |
260 | { | |
261 | int yes = 1; | |
262 | ||
263 | if (fdflags(fd, O_NONBLOCK, O_NONBLOCK, 0, 0)) { | |
264 | logmsg(0, LOG_ERR, "failed to set %s connection nonblocking: %s", | |
265 | what, strerror(errno)); | |
266 | return (-1); | |
267 | } | |
268 | ||
269 | if (setsockopt(fd, SOL_SOCKET, SO_OOBINLINE, &yes, sizeof(yes))) { | |
270 | logmsg(0, LOG_ERR, | |
271 | "failed to disable `out-of-band' data on %s connection: %s", | |
272 | what, strerror(errno)); | |
273 | return (-1); | |
274 | } | |
275 | ||
276 | return (0); | |
277 | } | |
278 | ||
c3794524 MW |
279 | /*----- Client output functions -------------------------------------------*/ |
280 | ||
281 | static void disconnect_client(struct client *c); | |
282 | ||
283 | /* Notification that output has been written. If successful, re-enable the | |
284 | * input buffer and prepare for another query. | |
285 | */ | |
9da480be MW |
286 | static void done_client_write(int err, void *p) |
287 | { | |
288 | struct client *c = p; | |
289 | ||
290 | if (!err) | |
291 | selbuf_enable(&c->b); | |
292 | else { | |
293 | logmsg(&c->q, LOG_ERR, "failed to send reply: %s", strerror(err)); | |
294 | disconnect_client(c); | |
295 | } | |
296 | } | |
297 | ||
c3794524 MW |
298 | /* Format the message FMT and queue it to be sent to the client. Client |
299 | * input will be disabled until the write completes. | |
300 | */ | |
bc23d2c7 MW |
301 | static void PRINTF_LIKE(2, 3) |
302 | write_to_client(struct client *c, const char *fmt, ...) | |
9da480be MW |
303 | { |
304 | va_list ap; | |
305 | char buf[WRBUFSZ]; | |
306 | ssize_t n; | |
307 | ||
308 | va_start(ap, fmt); | |
309 | n = vsnprintf(buf, sizeof(buf), fmt, ap); | |
310 | if (n < 0) { | |
311 | logmsg(&c->q, LOG_ERR, "failed to format output: %s", strerror(errno)); | |
312 | disconnect_client(c); | |
313 | return; | |
314 | } else if (n > sizeof(buf)) { | |
315 | logmsg(&c->q, LOG_ERR, "output too long for client send buffer"); | |
316 | disconnect_client(c); | |
317 | return; | |
318 | } | |
319 | ||
320 | selbuf_disable(&c->b); | |
321 | if (queue_write(&c->wb, buf, n)) { | |
322 | logmsg(&c->q, LOG_ERR, "write buffer overflow"); | |
323 | disconnect_client(c); | |
324 | } | |
325 | } | |
326 | ||
c3794524 MW |
327 | /* Format a reply to the client, with the form LPORT:RPORT:TY:TOK0[:TOK1]. |
328 | * Typically, TY will be `ERROR' or `USERID'. In the former case, TOK0 will | |
329 | * be the error token and TOK1 will be null; in the latter case, TOK0 will be | |
330 | * the operating system and TOK1 the user name. | |
331 | */ | |
c809f908 MW |
332 | static void reply(struct client *c, const char *ty, |
333 | const char *tok0, const char *tok1) | |
9da480be | 334 | { |
c809f908 MW |
335 | write_to_client(c, "%u,%u:%s:%s%s%s\r\n", |
336 | c->q.s[L].port, c->q.s[R].port, ty, | |
337 | tok0, tok1 ? ":" : "", tok1 ? tok1 : ""); | |
9da480be MW |
338 | } |
339 | ||
c3794524 | 340 | /* Mapping from error codes to their protocol tokens. */ |
bf4d9761 MW |
341 | const char *const errtok[] = { |
342 | #define DEFTOK(err, tok) tok, | |
343 | ERROR(DEFTOK) | |
344 | #undef DEFTOK | |
345 | }; | |
346 | ||
c3794524 | 347 | /* Report an error with code ERR to the client. */ |
9da480be MW |
348 | static void reply_error(struct client *c, unsigned err) |
349 | { | |
350 | assert(err < E_LIMIT); | |
c809f908 | 351 | reply(c, "ERROR", errtok[err], 0); |
9da480be MW |
352 | } |
353 | ||
c3794524 | 354 | /*----- NAT proxy functions -----------------------------------------------*/ |
9da480be | 355 | |
c3794524 MW |
356 | /* Cancel the proxy operation PX, closing the connection and releasing |
357 | * resources. This is used for both normal and unexpected closures. | |
358 | */ | |
359 | static void cancel_proxy(struct proxy *px) | |
9da480be | 360 | { |
c3794524 MW |
361 | if (px->fd == -1) |
362 | conn_kill(&px->cn); | |
363 | else { | |
364 | close(px->fd); | |
365 | selbuf_destroy(&px->b); | |
366 | free_writebuf(&px->wb); | |
9da480be | 367 | } |
c3794524 MW |
368 | selbuf_enable(&px->c->b); |
369 | px->c->px = 0; | |
370 | xfree(px); | |
9da480be MW |
371 | } |
372 | ||
c3794524 MW |
373 | /* Notification that a line (presumably a reply) has been received from the |
374 | * server. We should check it, log it, and propagate the answer back. | |
375 | * Whatever happens, this proxy operation is now complete. | |
376 | */ | |
9da480be MW |
377 | static void proxy_line(char *line, size_t sz, void *p) |
378 | { | |
379 | struct proxy *px = p; | |
380 | char buf[1024]; | |
381 | const char *q = line; | |
382 | unsigned lp, rp; | |
383 | ||
c3794524 | 384 | /* Trim trailing space. */ |
9da480be | 385 | while (sz && isspace((unsigned char)line[sz - 1])) sz--; |
9da480be | 386 | |
c3794524 | 387 | /* Parse the port numbers. These should match the request. */ |
9da480be MW |
388 | if (unum(&q, &lp, 1, 65535)) goto syntax; |
389 | skipws(&q); if (*q != ',') goto syntax; q++; | |
390 | if (unum(&q, &rp, 1, 65535)) goto syntax; | |
391 | skipws(&q); if (*q != ':') goto syntax; q++; | |
392 | if (lp != px->c->q.u.nat.port || rp != px->c->q.s[R].port) goto syntax; | |
c3794524 MW |
393 | |
394 | /* Find out what kind of reply this is. */ | |
9da480be MW |
395 | if (idtoken(&q, buf, sizeof(buf))) goto syntax; |
396 | skipws(&q); if (*q != ':') goto syntax; q++; | |
c3794524 | 397 | |
9da480be | 398 | if (strcmp(buf, "ERROR") == 0) { |
c3794524 MW |
399 | |
400 | /* Report the error without interpreting it. It might be meaningful to | |
401 | * the client. | |
402 | */ | |
9da480be MW |
403 | skipws(&q); |
404 | logmsg(&px->c->q, LOG_ERR, "proxy error from %s: %s", px->nat, q); | |
c809f908 | 405 | reply(px->c, "ERROR", q, 0); |
c3794524 | 406 | |
9da480be | 407 | } else if (strcmp(buf, "USERID") == 0) { |
c3794524 MW |
408 | |
409 | /* Parse out the operating system and user name, and pass them on. */ | |
9da480be MW |
410 | if (idtoken(&q, buf, sizeof(buf))) goto syntax; |
411 | skipws(&q); if (*q != ':') goto syntax; q++; | |
412 | skipws(&q); | |
413 | logmsg(&px->c->q, LOG_ERR, "user `%s'; proxy = %s, os = %s", | |
414 | q, px->nat, buf); | |
c809f908 | 415 | reply(px->c, "USERID", buf, q); |
c3794524 | 416 | |
9da480be MW |
417 | } else |
418 | goto syntax; | |
419 | goto done; | |
420 | ||
421 | syntax: | |
c3794524 | 422 | /* We didn't understand the message from the client. */ |
9da480be MW |
423 | logmsg(&px->c->q, LOG_ERR, "failed to parse response from %s", px->nat); |
424 | reply_error(px->c, E_UNKNOWN); | |
425 | done: | |
c3794524 | 426 | /* All finished, no matter what. */ |
9da480be MW |
427 | cancel_proxy(px); |
428 | } | |
429 | ||
c3794524 MW |
430 | /* Notification that we have written the query to the server. Await a |
431 | * response if successful. | |
432 | */ | |
9da480be MW |
433 | static void done_proxy_write(int err, void *p) |
434 | { | |
435 | struct proxy *px = p; | |
436 | ||
437 | if (err) { | |
438 | logmsg(&px->c->q, LOG_ERR, "failed to proxy query to %s: %s", | |
439 | px->nat, strerror(errno)); | |
440 | reply_error(px->c, E_UNKNOWN); | |
441 | cancel_proxy(px); | |
442 | return; | |
443 | } | |
444 | selbuf_enable(&px->b); | |
445 | } | |
446 | ||
c3794524 MW |
447 | /* Notification that the connection to the server is either established or |
448 | * failed. In the former case, queue the right query. | |
449 | */ | |
9da480be MW |
450 | static void proxy_connected(int fd, void *p) |
451 | { | |
452 | struct proxy *px = p; | |
453 | char buf[16]; | |
454 | int n; | |
455 | ||
c3794524 | 456 | /* If the connection failed then report the problem and give up. */ |
9da480be MW |
457 | if (fd < 0) { |
458 | logmsg(&px->c->q, LOG_ERR, | |
459 | "failed to make %s proxy connection to %s: %s", | |
bf4d9761 | 460 | px->c->l->ao->name, px->nat, strerror(errno)); |
9da480be MW |
461 | reply_error(px->c, E_UNKNOWN); |
462 | cancel_proxy(px); | |
463 | return; | |
464 | } | |
465 | ||
c3794524 | 466 | /* We're now ready to go, so set things up. */ |
9da480be MW |
467 | px->fd = fd; |
468 | selbuf_init(&px->b, &sel, fd, proxy_line, px); | |
469 | selbuf_setsize(&px->b, 1024); | |
470 | selbuf_disable(&px->b); | |
471 | init_writebuf(&px->wb, fd, done_proxy_write, px); | |
472 | ||
c3794524 MW |
473 | /* Write the query. This buffer is large enough because we've already |
474 | * range-checked the remote the port number and the local one came from the | |
475 | * kernel, which we trust not to do anything stupid. | |
476 | */ | |
9da480be MW |
477 | n = sprintf(buf, "%u,%u\r\n", px->c->q.u.nat.port, px->c->q.s[R].port); |
478 | queue_write(&px->wb, buf, n); | |
479 | } | |
480 | ||
c3794524 MW |
481 | /* Proxy the query through to a client machine for which we're providing NAT |
482 | * disservice. | |
483 | */ | |
9da480be MW |
484 | static void proxy_query(struct client *c) |
485 | { | |
486 | struct socket s; | |
487 | struct sockaddr_storage ss; | |
488 | size_t ssz; | |
489 | struct proxy *px; | |
9da480be MW |
490 | int fd; |
491 | ||
c3794524 | 492 | /* Allocate the context structure for the NAT. */ |
9da480be | 493 | px = xmalloc(sizeof(*px)); |
c3794524 MW |
494 | |
495 | /* We'll use the client host's address in lots of log messages, so we may | |
496 | * as well format it once and use it over and over. | |
497 | */ | |
bf4d9761 | 498 | inet_ntop(c->q.ao->af, &c->q.u.nat.addr, px->nat, sizeof(px->nat)); |
9da480be | 499 | |
c3794524 | 500 | /* Create the socket for the connection. */ |
bf4d9761 | 501 | if ((fd = socket(c->q.ao->af, SOCK_STREAM, 0)) < 0) { |
9da480be | 502 | logmsg(&c->q, LOG_ERR, "failed to make %s socket for proxy: %s", |
bf4d9761 | 503 | c->l->ao->name, strerror(errno)); |
9da480be MW |
504 | goto err_0; |
505 | } | |
95df134c | 506 | if (fix_up_socket(fd, "proxy")) goto err_1; |
9da480be | 507 | |
c3794524 MW |
508 | /* Set up the connection to the client host. The connection interface is a |
509 | * bit broken: if the connection completes immediately, then the callback | |
510 | * function is called synchronously, and that might decide to shut | |
511 | * everything down. So we must have fully initialized our context before | |
512 | * calling `conn_init', and mustn't touch it again afterwards -- since the | |
513 | * block may have been freed. | |
514 | */ | |
9da480be MW |
515 | s = c->q.u.nat; |
516 | s.port = 113; | |
bf4d9761 | 517 | c->l->ao->socket_to_sockaddr(&s, &ss, &ssz); |
9da480be | 518 | selbuf_disable(&c->b); |
79805e61 MW |
519 | c->px = px; px->c = c; |
520 | px->fd = -1; | |
9da480be MW |
521 | if (conn_init(&px->cn, &sel, fd, (struct sockaddr *)&ss, ssz, |
522 | proxy_connected, px)) { | |
523 | logmsg(&c->q, LOG_ERR, "failed to make %s proxy connection to %s: %s", | |
bf4d9761 | 524 | c->l->ao->name, px->nat, strerror(errno)); |
9da480be MW |
525 | goto err_2; |
526 | } | |
527 | ||
c3794524 | 528 | /* All ready to go. */ |
9da480be MW |
529 | return; |
530 | ||
c3794524 | 531 | /* Tidy up after various kinds of failures. */ |
9da480be MW |
532 | err_2: |
533 | selbuf_enable(&c->b); | |
534 | err_1: | |
535 | close(px->fd); | |
536 | err_0: | |
537 | xfree(px); | |
538 | reply_error(c, E_UNKNOWN); | |
539 | } | |
540 | ||
c3794524 MW |
541 | /*----- Client connection functions ---------------------------------------*/ |
542 | ||
543 | /* Disconnect a client, freeing up any associated resources. */ | |
544 | static void disconnect_client(struct client *c) | |
545 | { | |
546 | close(c->fd); | |
547 | selbuf_destroy(&c->b); | |
4f8fdcc1 | 548 | sel_rmtimer(&c->t); |
c3794524 MW |
549 | free_writebuf(&c->wb); |
550 | if (c->px) cancel_proxy(c->px); | |
551 | xfree(c); | |
552 | } | |
9da480be | 553 | |
4f8fdcc1 MW |
554 | /* Time out a client because it's been idle for too long. */ |
555 | static void timeout_client(struct timeval *tv, void *p) | |
556 | { | |
557 | struct client *c = p; | |
558 | logmsg(&c->q, LOG_NOTICE, "timing out idle or stuck client"); | |
559 | sel_addtimer(&sel, &c->t, tv, timeout_client, 0); | |
560 | disconnect_client(c); | |
561 | } | |
562 | ||
563 | /* Reset the client idle timer, as a result of activity. Set EXISTP if | |
564 | * there is an existing timer which needs to be removed. | |
565 | */ | |
566 | static void reset_client_timer(struct client *c, int existp) | |
567 | { | |
568 | struct timeval tv; | |
569 | ||
570 | gettimeofday(&tv, 0); | |
571 | tv.tv_sec += 30; | |
572 | if (existp) sel_rmtimer(&c->t); | |
573 | sel_addtimer(&sel, &c->t, &tv, timeout_client, c); | |
574 | } | |
575 | ||
c3794524 MW |
576 | /* Write a pseudorandom token into the buffer at P, which must have space for |
577 | * at least TOKENSZ bytes. | |
578 | */ | |
579 | #define TOKENRANDSZ 8 | |
580 | #define TOKENSZ ((4*TOKENRANDSZ + 5)/3) | |
9da480be MW |
581 | static void user_token(char *p) |
582 | { | |
9da480be MW |
583 | unsigned a = 0; |
584 | unsigned b = 0; | |
585 | int i; | |
c3794524 MW |
586 | static const char tokmap[64] = |
587 | "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789.-"; | |
9da480be | 588 | |
c3794524 MW |
589 | /* If there's not enough pseudorandom stuff lying around, then read more |
590 | * from the kernel. | |
591 | */ | |
592 | if (tokenptr + TOKENRANDSZ >= sizeof(tokenbuf)) { | |
9da480be MW |
593 | if (read(randfd, tokenbuf, sizeof(tokenbuf)) < sizeof(tokenbuf)) |
594 | die(1, "unexpected short read or error from `/dev/urandom'"); | |
595 | tokenptr = 0; | |
596 | } | |
597 | ||
c3794524 MW |
598 | /* Now encode the bytes using a slightly tweaked base-64 encoding. Read |
599 | * bytes into the accumulator and write out characters while there's | |
600 | * enough material. | |
601 | */ | |
602 | for (i = 0; i < TOKENRANDSZ; i++) { | |
9da480be MW |
603 | a = (a << 8) | tokenbuf[tokenptr++]; b += 8; |
604 | while (b >= 6) { | |
605 | b -= 6; | |
606 | *p++ = tokmap[(a >> b) & 0x3f]; | |
607 | } | |
608 | } | |
c3794524 MW |
609 | |
610 | /* If there's anything left in the accumulator then flush it out. */ | |
9da480be MW |
611 | if (b) |
612 | *p++ = tokmap[(a << (6 - b)) & 0x3f]; | |
c3794524 MW |
613 | |
614 | /* Null-terminate the token. */ | |
9da480be MW |
615 | *p++ = 0; |
616 | } | |
617 | ||
c3794524 MW |
618 | /* Notification that a line has been received from the client. Parse it, |
619 | * find out about the connection it's referring to, apply the relevant | |
620 | * policy rules, and produce a response. This is where almost everything | |
621 | * interesting happens. | |
622 | */ | |
9da480be MW |
623 | static void client_line(char *line, size_t len, void *p) |
624 | { | |
625 | struct client *c = p; | |
626 | const char *q; | |
627 | struct passwd *pw = 0; | |
628 | const struct policy *pol; | |
629 | dstr d = DSTR_INIT; | |
630 | struct policy upol = POLICY_INIT(A_LIMIT); | |
631 | struct policy_file pf; | |
632 | char buf[16]; | |
b9eb1a36 | 633 | int i, t; |
9da480be | 634 | |
c3794524 | 635 | /* If the connection has closed, then tidy stuff away. */ |
9da480be MW |
636 | c->q.s[L].port = c->q.s[R].port = 0; |
637 | if (!line) { | |
638 | disconnect_client(c); | |
639 | return; | |
640 | } | |
641 | ||
4f8fdcc1 MW |
642 | /* Client activity, so update the timer. */ |
643 | reset_client_timer(c, 1); | |
644 | ||
c3794524 MW |
645 | /* See if the policy file has changed since we last looked. If so, try to |
646 | * read the new version. | |
647 | */ | |
74716d82 MW |
648 | if (fwatch_update(&polfw, policyfile)) { |
649 | logmsg(0, LOG_INFO, "reload master policy file `%s'", policyfile); | |
650 | load_policy_file(policyfile, &policy); | |
9da480be MW |
651 | } |
652 | ||
c3794524 | 653 | /* Read the local and remote port numbers into the query structure. */ |
9da480be MW |
654 | q = line; |
655 | if (unum(&q, &c->q.s[L].port, 1, 65535)) goto bad; | |
656 | skipws(&q); if (*q != ',') goto bad; q++; | |
657 | if (unum(&q, &c->q.s[R].port, 1, 65535)) goto bad; | |
658 | skipws(&q); if (*q) goto bad; | |
659 | ||
c3794524 | 660 | /* Identify the connection. Act on the result. */ |
223e3e2b | 661 | c->q.s[R].addr = c->raddr; |
9da480be MW |
662 | identify(&c->q); |
663 | switch (c->q.resp) { | |
c3794524 | 664 | |
9da480be | 665 | case R_UID: |
c3794524 MW |
666 | /* We found a user. Track down the user's password entry, because |
667 | * we'll want that later. Most of the processing for this case is | |
668 | * below. | |
669 | */ | |
9da480be MW |
670 | if ((pw = getpwuid(c->q.u.uid)) == 0) { |
671 | logmsg(&c->q, LOG_ERR, "no passwd entry for user %d", c->q.u.uid); | |
672 | reply_error(c, E_NOUSER); | |
673 | return; | |
674 | } | |
675 | break; | |
c3794524 | 676 | |
9da480be | 677 | case R_NAT: |
c3794524 MW |
678 | /* We've acted as a NAT for this connection. Proxy the query through |
679 | * to the actal client host. | |
680 | */ | |
9da480be MW |
681 | proxy_query(c); |
682 | return; | |
c3794524 | 683 | |
9da480be | 684 | case R_ERROR: |
c3794524 MW |
685 | /* We failed to identify the connection for some reason. We should |
686 | * already have logged an error, so there's not much to do here. | |
687 | */ | |
9da480be MW |
688 | reply_error(c, c->q.u.error); |
689 | return; | |
c3794524 | 690 | |
9da480be | 691 | default: |
c3794524 | 692 | /* Something happened that we don't understand. */ |
9da480be MW |
693 | abort(); |
694 | } | |
695 | ||
c3794524 | 696 | /* Search the table of policy rules to find a match. */ |
9da480be MW |
697 | for (i = 0; i < DA_LEN(&policy); i++) { |
698 | pol = &DA(&policy)[i]; | |
699 | if (!match_policy(pol, &c->q)) continue; | |
c3794524 MW |
700 | |
701 | /* If this is something simple, then apply the resulting policy rule. */ | |
702 | if (pol->act.act != A_USER) goto match; | |
703 | ||
704 | /* The global policy has decided to let the user have a say, so we must | |
705 | * parse the user file. | |
706 | */ | |
9da480be MW |
707 | DRESET(&d); |
708 | dstr_putf(&d, "%s/.yaid.policy", pw->pw_dir); | |
17272ab8 | 709 | if (open_policy_file(&pf, d.buf, "user policy file", &c->q, OPF_NOENTOK)) |
9da480be | 710 | continue; |
b9eb1a36 | 711 | while ((t = read_policy_file(&pf)) < T_ERROR) { |
c3794524 | 712 | |
b9eb1a36 MW |
713 | /* Give up after 100 lines or if there's an error. If the user's |
714 | * policy is that complicated, something's gone very wrong. Or there's | |
715 | * too much commentary or something. | |
c3794524 | 716 | */ |
9da480be MW |
717 | if (pf.lno > 100) { |
718 | logmsg(&c->q, LOG_ERR, "%s:%d: user policy file too long", | |
719 | pf.name, pf.lno); | |
720 | break; | |
721 | } | |
c3794524 | 722 | |
b9eb1a36 MW |
723 | /* If this was a blank line, just go around again. */ |
724 | if (t != T_OK) continue; | |
725 | ||
c3794524 | 726 | /* If this isn't a match, go around for the next rule. */ |
9da480be | 727 | if (!match_policy(&pf.p, &c->q)) continue; |
c3794524 MW |
728 | |
729 | /* Check that the user is allowed to request this action. If not, see | |
730 | * if there's a more acceptable action later on. | |
731 | */ | |
9da480be MW |
732 | if (!(pol->act.u.user & (1 << pf.p.act.act))) { |
733 | logmsg(&c->q, LOG_ERR, | |
734 | "%s:%d: user action forbidden by global policy", | |
735 | pf.name, pf.lno); | |
736 | continue; | |
737 | } | |
c3794524 MW |
738 | |
739 | /* We've found a match, so grab it, close the file, and say we're | |
740 | * done. | |
741 | */ | |
9da480be MW |
742 | upol = pf.p; pol = &upol; |
743 | init_policy(&pf.p); | |
744 | close_policy_file(&pf); | |
c3794524 | 745 | DDESTROY(&d); |
9da480be MW |
746 | goto match; |
747 | } | |
748 | close_policy_file(&pf); | |
c3794524 | 749 | DDESTROY(&d); |
9da480be | 750 | } |
c3794524 MW |
751 | |
752 | /* No match: apply the built-in default policy. */ | |
9da480be MW |
753 | pol = &default_policy; |
754 | ||
755 | match: | |
9da480be | 756 | switch (pol->act.act) { |
c3794524 | 757 | |
9da480be | 758 | case A_NAME: |
c3794524 | 759 | /* Report the actual user's name. */ |
9da480be | 760 | logmsg(&c->q, LOG_INFO, "user `%s' (%d)", pw->pw_name, c->q.u.uid); |
c809f908 | 761 | reply(c, "USERID", "UNIX", pw->pw_name); |
9da480be | 762 | break; |
c3794524 | 763 | |
9da480be | 764 | case A_TOKEN: |
c3794524 | 765 | /* Report an arbitrary token which we can look up in our log file. */ |
9da480be MW |
766 | user_token(buf); |
767 | logmsg(&c->q, LOG_INFO, "user `%s' (%d); token = %s", | |
768 | pw->pw_name, c->q.u.uid, buf); | |
c809f908 | 769 | reply(c, "USERID", "OTHER", buf); |
9da480be | 770 | break; |
c3794524 | 771 | |
9da480be | 772 | case A_DENY: |
c3794524 | 773 | /* Deny that there's anyone there at all. */ |
9da480be MW |
774 | logmsg(&c->q, LOG_INFO, "user `%s' (%d); denying", |
775 | pw->pw_name, c->q.u.uid); | |
776 | break; | |
c3794524 | 777 | |
9da480be | 778 | case A_HIDE: |
c3794524 | 779 | /* Report the user as being hidden. */ |
9da480be MW |
780 | logmsg(&c->q, LOG_INFO, "user `%s' (%d); hiding", |
781 | pw->pw_name, c->q.u.uid); | |
782 | reply_error(c, E_HIDDEN); | |
783 | break; | |
c3794524 | 784 | |
9da480be | 785 | case A_LIE: |
c3794524 | 786 | /* Tell an egregious lie about who the user is. */ |
9da480be MW |
787 | logmsg(&c->q, LOG_INFO, "user `%s' (%d); lie = `%s'", |
788 | pw->pw_name, c->q.u.uid, pol->act.u.lie); | |
c809f908 | 789 | reply(c, "USERID", "UNIX", pol->act.u.lie); |
9da480be | 790 | break; |
c3794524 | 791 | |
9da480be | 792 | default: |
c3794524 | 793 | /* Something has gone very wrong. */ |
9da480be MW |
794 | abort(); |
795 | } | |
796 | ||
c3794524 | 797 | /* All done. */ |
9da480be MW |
798 | free_policy(&upol); |
799 | return; | |
800 | ||
801 | bad: | |
802 | logmsg(&c->q, LOG_ERR, "failed to parse query from client"); | |
803 | disconnect_client(c); | |
804 | } | |
805 | ||
c3794524 | 806 | /* Notification that a new client has connected. Prepare to read a query. */ |
9da480be MW |
807 | static void accept_client(int fd, unsigned mode, void *p) |
808 | { | |
809 | struct listen *l = p; | |
810 | struct client *c; | |
811 | struct sockaddr_storage ssr, ssl; | |
812 | size_t ssz = sizeof(ssr); | |
813 | int sk; | |
814 | ||
c3794524 | 815 | /* Accept the new connection. */ |
9da480be MW |
816 | if ((sk = accept(fd, (struct sockaddr *)&ssr, &ssz)) < 0) { |
817 | if (errno != EAGAIN && errno == EWOULDBLOCK) { | |
818 | logmsg(0, LOG_ERR, "failed to accept incoming %s connection: %s", | |
bf4d9761 | 819 | l->ao->name, strerror(errno)); |
9da480be MW |
820 | } |
821 | return; | |
822 | } | |
95df134c | 823 | if (fix_up_socket(sk, "incoming client")) { close(sk); return; } |
9da480be | 824 | |
c3794524 | 825 | /* Build a client block and fill it in. */ |
9da480be MW |
826 | c = xmalloc(sizeof(*c)); |
827 | c->l = l; | |
bf4d9761 | 828 | c->q.ao = l->ao; |
c3794524 MW |
829 | |
830 | /* Collect the local and remote addresses. */ | |
223e3e2b | 831 | l->ao->sockaddr_to_addr(&ssr, &c->raddr); |
9da480be MW |
832 | ssz = sizeof(ssl); |
833 | if (getsockname(sk, (struct sockaddr *)&ssl, &ssz)) { | |
834 | logmsg(0, LOG_ERR, | |
835 | "failed to read local address for incoming %s connection: %s", | |
bf4d9761 | 836 | l->ao->name, strerror(errno)); |
9da480be MW |
837 | close(sk); |
838 | xfree(c); | |
839 | return; | |
840 | } | |
bf4d9761 | 841 | l->ao->sockaddr_to_addr(&ssl, &c->q.s[L].addr); |
9da480be MW |
842 | c->q.s[L].port = c->q.s[R].port = 0; |
843 | ||
c3794524 | 844 | /* Set stuff up for reading the query and sending responses. */ |
9da480be MW |
845 | selbuf_init(&c->b, &sel, sk, client_line, c); |
846 | selbuf_setsize(&c->b, 1024); | |
4f8fdcc1 | 847 | reset_client_timer(c, 0); |
9da480be MW |
848 | c->fd = sk; |
849 | c->px = 0; | |
850 | init_writebuf(&c->wb, sk, done_client_write, c); | |
851 | } | |
852 | ||
c3794524 MW |
853 | /*----- Main code ---------------------------------------------------------*/ |
854 | ||
855 | /* Set up a listening socket for the address family described by AO, | |
856 | * listening on PORT. | |
857 | */ | |
bf4d9761 | 858 | static int make_listening_socket(const struct addrops *ao, int port) |
9da480be MW |
859 | { |
860 | int fd; | |
bf4d9761 MW |
861 | int yes = 1; |
862 | struct socket s; | |
9da480be MW |
863 | struct sockaddr_storage ss; |
864 | struct listen *l; | |
865 | size_t ssz; | |
866 | ||
c3794524 | 867 | /* Make the socket. */ |
bf4d9761 | 868 | if ((fd = socket(ao->af, SOCK_STREAM, 0)) < 0) { |
a20696ca | 869 | if (errno == EAFNOSUPPORT) return (-1); |
9da480be | 870 | die(1, "failed to create %s listening socket: %s", |
bf4d9761 | 871 | ao->name, strerror(errno)); |
9da480be | 872 | } |
c3794524 MW |
873 | |
874 | /* Build the appropriate local address. */ | |
bf4d9761 MW |
875 | s.addr = *ao->any; |
876 | s.port = port; | |
877 | ao->socket_to_sockaddr(&s, &ss, &ssz); | |
c3794524 MW |
878 | |
879 | /* Perform any initialization specific to the address type. */ | |
bf4d9761 MW |
880 | if (ao->init_listen_socket(fd)) { |
881 | die(1, "failed to initialize %s listening socket: %s", | |
882 | ao->name, strerror(errno)); | |
883 | } | |
c3794524 MW |
884 | |
885 | /* Bind to the address. */ | |
886 | setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)); | |
bf4d9761 MW |
887 | if (bind(fd, (struct sockaddr *)&ss, ssz)) { |
888 | die(1, "failed to bind %s listening socket: %s", | |
889 | ao->name, strerror(errno)); | |
9da480be | 890 | } |
c3794524 MW |
891 | |
892 | /* Avoid unpleasant race conditions. */ | |
bf4d9761 | 893 | if (fdflags(fd, O_NONBLOCK, O_NONBLOCK, 0, 0)) { |
9da480be | 894 | die(1, "failed to set %s listening socket nonblocking: %s", |
bf4d9761 | 895 | ao->name, strerror(errno)); |
9da480be | 896 | } |
c3794524 MW |
897 | |
898 | /* Prepare to listen. */ | |
9da480be | 899 | if (listen(fd, 5)) |
bf4d9761 | 900 | die(1, "failed to listen for %s: %s", ao->name, strerror(errno)); |
9da480be | 901 | |
c3794524 | 902 | /* Make a record of all of this. */ |
9da480be | 903 | l = xmalloc(sizeof(*l)); |
bf4d9761 | 904 | l->ao = ao; |
9da480be MW |
905 | sel_initfile(&sel, &l->f, fd, SEL_READ, accept_client, l); |
906 | sel_addfile(&l->f); | |
907 | ||
c3794524 | 908 | /* Done. */ |
a20696ca | 909 | return (0); |
9da480be MW |
910 | } |
911 | ||
74716d82 | 912 | /* Quit because of a fatal signal. */ |
bc23d2c7 | 913 | static void NORETURN quit(int sig, void *p) |
74716d82 MW |
914 | { |
915 | const char *signame = p; | |
916 | ||
917 | logmsg(0, LOG_NOTICE, "shutting down on %s", signame); | |
918 | if (pidfile) unlink(pidfile); | |
919 | exit(0); | |
920 | } | |
921 | ||
922 | /* Answer whether the string pointed to by P consists entirely of digits. */ | |
923 | static int numericp(const char *p) | |
924 | { | |
925 | while (*p) | |
926 | if (!isdigit((unsigned char)*p++)) return (0); | |
927 | return (1); | |
928 | } | |
929 | ||
930 | static void usage(FILE *fp) | |
931 | { | |
932 | pquis(fp, "Usage: $ [-Dl] [-G GROUP] [-U USER] [-P FILE] " | |
933 | "[-c FILE] [-p PORT]\n"); | |
934 | } | |
935 | ||
936 | static void version(FILE *fp) | |
937 | { pquis(fp, "$, version " VERSION "\n"); } | |
938 | ||
939 | static void help(FILE *fp) | |
940 | { | |
941 | version(fp); fputc('\n', fp); | |
942 | usage(fp); | |
943 | fputs("\n\ | |
944 | Yet Another Ident Daemon. Really, the world doesn't need such a thing.\n\ | |
945 | It's just a shame none of the others do the right things.\n\ | |
946 | \n\ | |
947 | Options:\n\ | |
948 | \n\ | |
949 | -h, --help Show this help message.\n\ | |
950 | -v, --version Show the version number.\n\ | |
951 | -u, --usage Show a very short usage summary.\n\ | |
952 | \n\ | |
953 | -D, --daemon Become a daemon, running in the background.\n\ | |
954 | -G, --group=GROUP Set group after initialization.\n\ | |
955 | -P, --pidfile=FILE Write process id to FILE.\n\ | |
956 | -U, --user=USER Set user after initialization.\n\ | |
957 | -c, --config=FILE Read global policy from FILE.\n\ | |
958 | -l, --syslog Write log messages using syslog(3).\n\ | |
959 | -p, --port=PORT Listen for connections on this port.\n", | |
960 | fp); | |
961 | } | |
962 | ||
9da480be MW |
963 | int main(int argc, char *argv[]) |
964 | { | |
965 | int port = 113; | |
74716d82 MW |
966 | uid_t u = -1; |
967 | gid_t g = -1; | |
968 | struct passwd *pw = 0; | |
969 | struct group *gr; | |
970 | struct servent *s; | |
971 | sig sigint, sigterm; | |
972 | FILE *fp = 0; | |
973 | int i; | |
974 | unsigned f = 0; | |
975 | #define f_bogus 1u | |
976 | #define f_daemon 2u | |
bf4d9761 MW |
977 | const struct addrops *ao; |
978 | int any = 0; | |
9da480be MW |
979 | |
980 | ego(argv[0]); | |
981 | ||
74716d82 MW |
982 | /* Parse command-line options. */ |
983 | for (;;) { | |
984 | const struct option opts[] = { | |
985 | { "help", 0, 0, 'h' }, | |
986 | { "version", 0, 0, 'v' }, | |
987 | { "usage", 0, 0, 'u' }, | |
988 | { "daemon", 0, 0, 'D' }, | |
989 | { "group", OPTF_ARGREQ, 0, 'G' }, | |
990 | { "pidfile", OPTF_ARGREQ, 0, 'P' }, | |
991 | { "user", OPTF_ARGREQ, 0, 'U' }, | |
992 | { "config", OPTF_ARGREQ, 0, 'c' }, | |
993 | { "syslog", 0, 0, 'l' }, | |
994 | { "port", OPTF_ARGREQ, 0, 'p' }, | |
995 | { 0, 0, 0, 0 } | |
996 | }; | |
997 | ||
998 | if ((i = mdwopt(argc, argv, "hvuDG:P:U:c:lp:", opts, 0, 0, 0)) < 0) | |
999 | break; | |
1000 | switch (i) { | |
1001 | case 'h': help(stdout); exit(0); | |
1002 | case 'v': version(stdout); exit(0); | |
1003 | case 'u': usage(stdout); exit(0); | |
1004 | case 'D': f |= f_daemon; break; | |
1005 | case 'P': pidfile = optarg; break; | |
1006 | case 'c': policyfile = optarg; break; | |
1007 | case 'l': flags |= F_SYSLOG; break; | |
1008 | case 'G': | |
1009 | if (numericp(optarg)) | |
1010 | g = atoi(optarg); | |
1011 | else if ((gr = getgrnam(optarg)) == 0) | |
1012 | die(1, "unknown group `%s'", optarg); | |
1013 | else | |
1014 | g = gr->gr_gid; | |
1015 | break; | |
1016 | case 'U': | |
1017 | if (numericp(optarg)) | |
1018 | u = atoi(optarg); | |
1019 | else if ((pw = getpwnam(optarg)) == 0) | |
1020 | die(1, "unknown user `%s'", optarg); | |
1021 | else | |
1022 | u = pw->pw_uid; | |
1023 | break; | |
1024 | case 'p': | |
1025 | if (numericp(optarg)) | |
1026 | port = atoi(optarg); | |
1027 | else if ((s = getservbyname(optarg, "tcp")) == 0) | |
1028 | die(1, "unknown service name `%s'", optarg); | |
1029 | else | |
1030 | port = ntohs(s->s_port); | |
1031 | break; | |
1032 | default: f |= f_bogus; break; | |
1033 | } | |
1034 | } | |
1035 | if (optind < argc) f |= f_bogus; | |
1036 | if (f & f_bogus) { usage(stderr); exit(1); } | |
1037 | ||
1038 | /* If a user has been requested, but no group, then find the user's primary | |
1039 | * group. If the user was given by name, then we already have a password | |
1040 | * entry and should use that, in case two differently-named users have the | |
1041 | * same uid but distinct gids. | |
1042 | */ | |
1043 | if (u != -1 && g == -1) { | |
1044 | if (!pw && (pw = getpwuid(u)) == 0) { | |
1045 | die(1, "failed to find password entry for user %d: " | |
1046 | "request group explicitly", u); | |
1047 | } | |
1048 | g = pw->pw_gid; | |
1049 | } | |
1050 | ||
1051 | /* Initialize system-specific machinery. */ | |
b093b41d | 1052 | init_sys(); |
74716d82 MW |
1053 | |
1054 | /* Load the global policy rules. */ | |
1055 | fwatch_init(&polfw, policyfile); | |
1056 | if (load_policy_file(policyfile, &policy)) | |
9da480be | 1057 | exit(1); |
9da480be | 1058 | |
74716d82 | 1059 | /* Open the random data source. */ |
9da480be MW |
1060 | if ((randfd = open("/dev/urandom", O_RDONLY)) < 0) { |
1061 | die(1, "failed to open `/dev/urandom' for reading: %s", | |
1062 | strerror(errno)); | |
1063 | } | |
1064 | ||
74716d82 | 1065 | /* Set up the I/O event system. */ |
9da480be | 1066 | sel_init(&sel); |
74716d82 MW |
1067 | |
1068 | /* Watch for some interesting signals. */ | |
1069 | sig_init(&sel); | |
1070 | sig_add(&sigint, SIGINT, quit, "SIGINT"); | |
1071 | sig_add(&sigterm, SIGTERM, quit, "SIGTERM"); | |
1072 | ||
1073 | /* Listen for incoming connections. */ | |
bf4d9761 MW |
1074 | for (ao = addroptab; ao->name; ao++) |
1075 | if (!make_listening_socket(ao, port)) any = 1; | |
74716d82 MW |
1076 | if (!any) die(1, "no IP protocols supported"); |
1077 | ||
1078 | /* Open the pidfile now, in case it's somewhere we can't write. */ | |
1079 | if (pidfile && (fp = fopen(pidfile, "w")) == 0) { | |
1080 | die(1, "failed to open pidfile `%s' for writing: %s", | |
1081 | pidfile, strerror(errno)); | |
1082 | } | |
1083 | ||
1084 | /* If we're meant to use syslog, then open the log. */ | |
1085 | if (flags & F_SYSLOG) | |
1086 | openlog(QUIS, 0, LOG_DAEMON); | |
1087 | ||
1088 | /* Drop privileges. */ | |
1089 | if ((g != -1 && (setegid(g) || setgid(g) || | |
1090 | (getuid() == 0 && setgroups(1, &g)))) || | |
1091 | (u != -1 && setuid(u))) | |
1092 | die(1, "failed to drop privileges: %s", strerror(errno)); | |
9da480be | 1093 | |
74716d82 MW |
1094 | /* Become a background process, if requested. */ |
1095 | if ((f & f_daemon) && daemonize()) | |
1096 | die(1, "failed to become daemon: %s", strerror(errno)); | |
1097 | ||
1098 | /* Write the process id to the pidfile. */ | |
1099 | if (fp) { | |
1100 | fprintf(fp, "%d\n", getpid()); | |
1101 | fclose(fp); | |
1102 | } | |
1103 | ||
1104 | /* And now we're going. */ | |
1105 | flags |= F_RUNNING; | |
1106 | ||
1107 | /* Read events and process them. */ | |
1108 | for (;;) { | |
1109 | if (sel_select(&sel) && errno != EINTR) | |
1110 | die(1, "select failed: %s", strerror(errno)); | |
1111 | } | |
9da480be | 1112 | |
74716d82 | 1113 | /* This just keeps the compiler happy. */ |
9da480be MW |
1114 | return (0); |
1115 | } | |
1116 | ||
1117 | /*----- That's all, folks -------------------------------------------------*/ |