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root/svn/ircd-hybrid/trunk/src/auth.c
Revision: 4309
Committed: Tue Jul 29 17:24:25 2014 UTC (11 years, 1 month ago) by michael
Content type: text/x-csrc
File size: 14648 byte(s)
Log Message:
- Backported auth code related cleanups from newio branch

File Contents

# Content
1 /*
2 * ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3 *
4 * Copyright (c) 1997-2014 ircd-hybrid development team
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
19 * USA
20 */
21
22 /*! \file auth.c
23 * \brief Functions for querying a users ident.
24 * \version $Id$
25 */
26
27 /*
28 * Changes:
29 * July 6, 1999 - Rewrote most of the code here. When a client connects
30 * to the server and passes initial socket validation checks, it
31 * is owned by this module (auth) which returns it to the rest of the
32 * server when dns and auth queries are finished. Until the client is
33 * released, the server does not know it exists and does not process
34 * any messages from it.
35 * --Bleep Thomas Helvey <tomh@inxpress.net>
36 */
37
38 #include "stdinc.h"
39 #include "list.h"
40 #include "ircd_defs.h"
41 #include "fdlist.h"
42 #include "auth.h"
43 #include "conf.h"
44 #include "client.h"
45 #include "event.h"
46 #include "irc_string.h"
47 #include "ircd.h"
48 #include "packet.h"
49 #include "res.h"
50 #include "s_bsd.h"
51 #include "log.h"
52 #include "send.h"
53 #include "mempool.h"
54
55
56 static const char *const HeaderMessages[] =
57 {
58 ":*** Looking up your hostname",
59 ":*** Found your hostname",
60 ":*** Couldn't look up your hostname",
61 ":*** Checking Ident",
62 ":*** Got Ident response",
63 ":*** No Ident response",
64 ":*** Your forward and reverse DNS do not match, ignoring hostname",
65 ":*** Your hostname is too long, ignoring hostname"
66 };
67
68 enum
69 {
70 REPORT_DO_DNS,
71 REPORT_FIN_DNS,
72 REPORT_FAIL_DNS,
73 REPORT_DO_ID,
74 REPORT_FIN_ID,
75 REPORT_FAIL_ID,
76 REPORT_IP_MISMATCH,
77 REPORT_HOST_TOOLONG
78 };
79
80 #define sendheader(c, i) sendto_one_notice((c), &me, HeaderMessages[(i)])
81
82 static dlink_list auth_pending_list;
83 static PF read_auth_reply;
84 static CNCB auth_connect_callback;
85
86
87 /*
88 * make_auth_request - allocate a new auth request
89 */
90 static struct AuthRequest *
91 make_auth_request(struct Client *client)
92 {
93 struct AuthRequest *request = &client->localClient->auth;
94
95 memset(request, 0, sizeof(*request));
96
97 request->client = client;
98 request->timeout = CurrentTime + CONNECTTIMEOUT;
99
100 return request;
101 }
102
103 /*
104 * release_auth_client - release auth client from auth system
105 * this adds the client into the local client lists so it can be read by
106 * the main io processing loop
107 */
108 void
109 release_auth_client(struct AuthRequest *auth)
110 {
111 struct Client *client = auth->client;
112
113 if (IsDoingAuth(auth) || IsDNSPending(auth))
114 return;
115
116 if (IsInAuth(auth))
117 {
118 dlinkDelete(&auth->node, &auth_pending_list);
119 ClearInAuth(auth);
120 }
121
122 /*
123 * When a client has auth'ed, we want to start reading what it sends
124 * us. This is what read_packet() does.
125 * -- adrian
126 */
127 client->localClient->allow_read = MAX_FLOOD;
128 comm_setflush(&client->localClient->fd, 1000, flood_recalc, client);
129
130 client->localClient->since = CurrentTime;
131 client->localClient->lasttime = CurrentTime;
132 client->localClient->firsttime = CurrentTime;
133 client->flags |= FLAGS_FINISHED_AUTH;
134
135 read_packet(&client->localClient->fd, client);
136 }
137
138 /*
139 * auth_dns_callback - called when resolver query finishes
140 * if the query resulted in a successful search, name will contain
141 * a non-NULL pointer, otherwise name will be NULL.
142 * set the client on it's way to a connection completion, regardless
143 * of success of failure
144 */
145 static void
146 auth_dns_callback(void *vptr, const struct irc_ssaddr *addr, const char *name)
147 {
148 struct AuthRequest *auth = vptr;
149
150 ClearDNSPending(auth);
151
152 if (name)
153 {
154 const struct sockaddr_in *v4, *v4dns;
155 #ifdef IPV6
156 const struct sockaddr_in6 *v6, *v6dns;
157 #endif
158 int good = 1;
159
160 #ifdef IPV6
161 if (auth->client->localClient->ip.ss.ss_family == AF_INET6)
162 {
163 v6 = (const struct sockaddr_in6 *)&auth->client->localClient->ip;
164 v6dns = (const struct sockaddr_in6 *)addr;
165
166 if (memcmp(&v6->sin6_addr, &v6dns->sin6_addr, sizeof(struct in6_addr)) != 0)
167 {
168 sendheader(auth->client, REPORT_IP_MISMATCH);
169 good = 0;
170 }
171 }
172 else
173 #endif
174 {
175 v4 = (const struct sockaddr_in *)&auth->client->localClient->ip;
176 v4dns = (const struct sockaddr_in *)addr;
177
178 if (v4->sin_addr.s_addr != v4dns->sin_addr.s_addr)
179 {
180 sendheader(auth->client, REPORT_IP_MISMATCH);
181 good = 0;
182 }
183 }
184
185 if (good && strlen(name) <= HOSTLEN)
186 {
187 strlcpy(auth->client->host, name,
188 sizeof(auth->client->host));
189 sendheader(auth->client, REPORT_FIN_DNS);
190 }
191 else if (strlen(name) > HOSTLEN)
192 sendheader(auth->client, REPORT_HOST_TOOLONG);
193 }
194 else
195 sendheader(auth->client, REPORT_FAIL_DNS);
196
197 release_auth_client(auth);
198 }
199
200 /*
201 * authsenderr - handle auth send errors
202 */
203 static void
204 auth_error(struct AuthRequest *auth)
205 {
206 ++ServerStats.is_abad;
207
208 fd_close(&auth->fd);
209
210 ClearAuth(auth);
211
212 sendheader(auth->client, REPORT_FAIL_ID);
213
214 release_auth_client(auth);
215 }
216
217 /*
218 * start_auth_query - Flag the client to show that an attempt to
219 * contact the ident server on
220 * the client's host. The connect and subsequently the socket are all put
221 * into 'non-blocking' mode. Should the connect or any later phase of the
222 * identifing process fail, it is aborted and the user is given a username
223 * of "unknown".
224 */
225 static int
226 start_auth_query(struct AuthRequest *auth)
227 {
228 struct irc_ssaddr localaddr;
229 socklen_t locallen = sizeof(struct irc_ssaddr);
230 #ifdef IPV6
231 struct sockaddr_in6 *v6;
232 #else
233 struct sockaddr_in *v4;
234 #endif
235
236 /* open a socket of the same type as the client socket */
237 if (comm_open(&auth->fd, auth->client->localClient->ip.ss.ss_family,
238 SOCK_STREAM, 0, "ident") == -1)
239 {
240 report_error(L_ALL, "creating auth stream socket %s:%s",
241 get_client_name(auth->client, SHOW_IP), errno);
242 ilog(LOG_TYPE_IRCD, "Unable to create auth socket for %s",
243 get_client_name(auth->client, SHOW_IP));
244 ++ServerStats.is_abad;
245 return 0;
246 }
247
248 sendheader(auth->client, REPORT_DO_ID);
249
250 /*
251 * get the local address of the client and bind to that to
252 * make the auth request. This used to be done only for
253 * ifdef VIRTUAL_HOST, but needs to be done for all clients
254 * since the ident request must originate from that same address--
255 * and machines with multiple IP addresses are common now
256 */
257 memset(&localaddr, 0, locallen);
258 getsockname(auth->client->localClient->fd.fd, (struct sockaddr*)&localaddr,
259 &locallen);
260
261 #ifdef IPV6
262 remove_ipv6_mapping(&localaddr);
263 v6 = (struct sockaddr_in6 *)&localaddr;
264 v6->sin6_port = htons(0);
265 #else
266 localaddr.ss_len = locallen;
267 v4 = (struct sockaddr_in *)&localaddr;
268 v4->sin_port = htons(0);
269 #endif
270 localaddr.ss_port = htons(0);
271
272 comm_connect_tcp(&auth->fd, auth->client->sockhost, RFC1413_PORT,
273 (struct sockaddr *)&localaddr, localaddr.ss_len, auth_connect_callback,
274 auth, auth->client->localClient->ip.ss.ss_family,
275 GlobalSetOptions.ident_timeout);
276 return 1; /* We suceed here for now */
277 }
278
279 /*
280 * start_auth
281 *
282 * inputs - pointer to client to auth
283 * output - NONE
284 * side effects - starts auth (identd) and dns queries for a client
285 */
286 void
287 start_auth(struct Client *client_p)
288 {
289 struct AuthRequest *auth = NULL;
290
291 assert(client_p);
292
293 auth = make_auth_request(client_p);
294 SetInAuth(auth);
295 dlinkAddTail(auth, &auth->node, &auth_pending_list);
296
297 sendheader(client_p, REPORT_DO_DNS);
298
299 SetDNSPending(auth);
300
301 if (ConfigFileEntry.disable_auth == 0)
302 {
303 SetDoingAuth(auth);
304 start_auth_query(auth);
305 }
306
307 gethost_byaddr(auth_dns_callback, auth, &client_p->localClient->ip);
308 }
309
310 /*
311 * timeout_auth_queries - timeout resolver and identd requests
312 * allow clients through if requests failed
313 */
314 static void
315 timeout_auth_queries_event(void *notused)
316 {
317 dlink_node *ptr = NULL, *ptr_next = NULL;
318
319 DLINK_FOREACH_SAFE(ptr, ptr_next, auth_pending_list.head)
320 {
321 struct AuthRequest *auth = ptr->data;
322
323 if (auth->timeout > CurrentTime)
324 break;
325
326 if (IsDoingAuth(auth))
327 {
328 ++ServerStats.is_abad;
329 fd_close(&auth->fd);
330 ClearAuth(auth);
331 sendheader(auth->client, REPORT_FAIL_ID);
332 }
333
334 if (IsDNSPending(auth))
335 {
336 delete_resolver_queries(auth);
337 ClearDNSPending(auth);
338 sendheader(auth->client, REPORT_FAIL_DNS);
339 }
340
341 ilog(LOG_TYPE_IRCD, "DNS/AUTH timeout %s",
342 get_client_name(auth->client, SHOW_IP));
343 release_auth_client(auth);
344 }
345 }
346
347 /*
348 * auth_connect_callback() - deal with the result of comm_connect_tcp()
349 *
350 * If the connection failed, we simply close the auth fd and report
351 * a failure. If the connection suceeded send the ident server a query
352 * giving "theirport , ourport". The write is only attempted *once* so
353 * it is deemed to be a fail if the entire write doesn't write all the
354 * data given. This shouldnt be a problem since the socket should have
355 * a write buffer far greater than this message to store it in should
356 * problems arise. -avalon
357 */
358 static void
359 auth_connect_callback(fde_t *fd, int error, void *data)
360 {
361 struct AuthRequest *auth = data;
362 struct irc_ssaddr us;
363 struct irc_ssaddr them;
364 char authbuf[32];
365 socklen_t ulen = sizeof(struct irc_ssaddr);
366 socklen_t tlen = sizeof(struct irc_ssaddr);
367 uint16_t uport, tport;
368 #ifdef IPV6
369 struct sockaddr_in6 *v6;
370 #else
371 struct sockaddr_in *v4;
372 #endif
373
374 if (error != COMM_OK)
375 {
376 auth_error(auth);
377 return;
378 }
379
380 if (getsockname(auth->client->localClient->fd.fd, (struct sockaddr *)&us, &ulen) ||
381 getpeername(auth->client->localClient->fd.fd, (struct sockaddr *)&them, &tlen))
382 {
383 ilog(LOG_TYPE_IRCD, "auth get{sock,peer}name error for %s",
384 get_client_name(auth->client, SHOW_IP));
385 auth_error(auth);
386 return;
387 }
388
389 #ifdef IPV6
390 v6 = (struct sockaddr_in6 *)&us;
391 uport = ntohs(v6->sin6_port);
392 v6 = (struct sockaddr_in6 *)&them;
393 tport = ntohs(v6->sin6_port);
394 remove_ipv6_mapping(&us);
395 remove_ipv6_mapping(&them);
396 #else
397 v4 = (struct sockaddr_in *)&us;
398 uport = ntohs(v4->sin_port);
399 v4 = (struct sockaddr_in *)&them;
400 tport = ntohs(v4->sin_port);
401 us.ss_len = ulen;
402 them.ss_len = tlen;
403 #endif
404
405 snprintf(authbuf, sizeof(authbuf), "%u, %u\r\n", tport, uport);
406
407 if (send(fd->fd, authbuf, strlen(authbuf), 0) == -1)
408 {
409 auth_error(auth);
410 return;
411 }
412
413 comm_setselect(fd, COMM_SELECT_READ, read_auth_reply, auth, 0);
414 }
415
416 /** Enum used to index ident reply fields in a human-readable way. */
417 enum IdentReplyFields
418 {
419 IDENT_PORT_NUMBERS,
420 IDENT_REPLY_TYPE,
421 IDENT_OS_TYPE,
422 IDENT_INFO,
423 USERID_TOKEN_COUNT
424 };
425
426 /** Parse an ident reply line and extract the userid from it.
427 * \param reply The ident reply line.
428 * \return The userid, or NULL on parse failure.
429 */
430 static const char *
431 check_ident_reply(char *reply)
432 {
433 char *token = NULL, *end = NULL;
434 char *vector[USERID_TOKEN_COUNT];
435 int count = token_vector(reply, ':', vector, USERID_TOKEN_COUNT);
436
437 if (USERID_TOKEN_COUNT != count)
438 return NULL;
439
440 /*
441 * Second token is the reply type
442 */
443 token = vector[IDENT_REPLY_TYPE];
444
445 if (EmptyString(token))
446 return NULL;
447
448 while (IsSpace(*token))
449 ++token;
450
451 if (strncmp(token, "USERID", 6))
452 return NULL;
453
454 /*
455 * Third token is the os type
456 */
457 token = vector[IDENT_OS_TYPE];
458
459 if (EmptyString(token))
460 return NULL;
461
462 while (IsSpace(*token))
463 ++token;
464
465 /*
466 * Unless "OTHER" is specified as the operating system type, the server
467 * is expected to return the "normal" user identification of the owner
468 * of this connection. "Normal" in this context may be taken to mean a
469 * string of characters which uniquely identifies the connection owner
470 * such as a user identifier assigned by the system administrator and
471 * used by such user as a mail identifier, or as the "user" part of a
472 * user/password pair used to gain access to system resources. When an
473 * operating system is specified (e.g., anything but "OTHER"), the user
474 * identifier is expected to be in a more or less immediately useful
475 * form - e.g., something that could be used as an argument to "finger"
476 * or as a mail address.
477 */
478 if (!strncmp(token, "OTHER", 5))
479 return NULL;
480
481 /*
482 * Fourth token is the username
483 */
484 token = vector[IDENT_INFO];
485
486 if (EmptyString(token))
487 return NULL;
488
489 while (IsSpace(*token))
490 ++token;
491
492 while (*token == '~' || *token == '^')
493 ++token;
494
495 /*
496 * Look for the end of the username, terminators are '\0, @, <SPACE>, :'
497 */
498 for (end = token; *end; ++end)
499 if (IsSpace(*end) || '@' == *end || ':' == *end)
500 break;
501 *end = '\0';
502
503 return token;
504 }
505
506 /*
507 * read_auth_reply - read the reply (if any) from the ident server
508 * we connected to.
509 * We only give it one shot, if the reply isn't good the first time
510 * fail the authentication entirely. --Bleep
511 */
512 static void
513 read_auth_reply(fde_t *fd, void *data)
514 {
515 struct AuthRequest *auth = data;
516 const char *username = NULL;
517 ssize_t len = 0;
518 char buf[RFC1413_BUFSIZ + 1];
519
520 if ((len = recv(fd->fd, buf, RFC1413_BUFSIZ, 0)) > 0)
521 {
522 buf[len] = '\0';
523 username = check_ident_reply(buf);
524 }
525
526 fd_close(fd);
527
528 ClearAuth(auth);
529
530 if (EmptyString(username))
531 {
532 sendheader(auth->client, REPORT_FAIL_ID);
533 ++ServerStats.is_abad;
534 }
535 else
536 {
537 strlcpy(auth->client->username, username, sizeof(auth->client->username));
538 sendheader(auth->client, REPORT_FIN_ID);
539 ++ServerStats.is_asuc;
540 SetGotId(auth->client);
541 }
542
543 release_auth_client(auth);
544 }
545
546 /*
547 * delete_auth()
548 */
549 void
550 delete_auth(struct AuthRequest *auth)
551 {
552 if (IsDNSPending(auth))
553 delete_resolver_queries(auth);
554
555 if (IsDoingAuth(auth))
556 fd_close(&auth->fd);
557
558 if (IsInAuth(auth))
559 {
560 dlinkDelete(&auth->node, &auth_pending_list);
561 ClearInAuth(auth);
562 }
563 }
564
565 /* auth_init
566 *
567 * Initialise the auth code
568 */
569 void
570 auth_init(void)
571 {
572 static struct event timeout_auth_queries =
573 {
574 .name = "timeout_auth_queries_event",
575 .handler = timeout_auth_queries_event,
576 .when = 1
577 };
578
579 event_add(&timeout_auth_queries, NULL);
580 }

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svn:eol-style native
svn:keywords Id Revision