citadel
About: Citadel is an advanced messaging and collaboration system for groupware and BBS applications (preferred OS: Linux).
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sysdep.c
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1// Citadel "system dependent" stuff.
2//
3// Here's where we (hopefully) have most parts of the Citadel server that
4// might need tweaking when run on different operating system variants.
5//
6// Copyright (c) 1987-2021 by the citadel.org team
7//
8// This program is open source software; you can redistribute it and/or modify
9// it under the terms of the GNU General Public License, version 3.
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#include "sysdep.h"
17#include <stdlib.h>
18#include <unistd.h>
19#include <sys/stat.h>
20#include <errno.h>
21#include <signal.h>
22#include <stdio.h>
23#include <syslog.h>
24#include <sys/syslog.h>
25#include <execinfo.h>
26#include <netdb.h>
27#include <sys/un.h>
28#include <sys/types.h>
29#include <sys/socket.h>
30#include <netinet/in.h>
31#include <arpa/inet.h>
32#include <netinet/tcp.h>
33#include <arpa/inet.h>
34#define SHOW_ME_VAPPEND_PRINTF
35#include <libcitadel.h>
36#include "citserver.h"
37#include "config.h"
38#include "ctdl_module.h"
39#include "sysdep_decls.h"
40#include "modules/crypto/serv_crypto.h" // Needed for init_ssl, client_write_ssl, client_read_ssl, destruct_ssl
41#include "housekeeping.h"
42#include "context.h"
43
44// Signal handler to shut down the server.
45volatile int exit_signal = 0;
46volatile int shutdown_and_halt = 0;
47volatile int restart_server = 0;
48volatile int running_as_daemon = 0;
49
50
51static RETSIGTYPE signal_cleanup(int signum) {
52 syslog(LOG_DEBUG, "sysdep: caught signal %d", signum);
53 exit_signal = signum;
55}
56
57
58// Some initialization stuff...
59void init_sysdep(void) {
60 sigset_t set;
61
62 // Avoid vulnerabilities related to FD_SETSIZE if we can.
63#ifdef FD_SETSIZE
64#ifdef RLIMIT_NOFILE
65 struct rlimit rl;
66 getrlimit(RLIMIT_NOFILE, &rl);
67 rl.rlim_cur = FD_SETSIZE;
68 rl.rlim_max = FD_SETSIZE;
69 setrlimit(RLIMIT_NOFILE, &rl);
70#endif
71#endif
72
73 // If we've got OpenSSL, we're going to use it.
74#ifdef HAVE_OPENSSL
75 init_ssl();
76#endif
77
78 if (pthread_key_create(&ThreadKey, NULL) != 0) { // TSD for threads
79 syslog(LOG_ERR, "pthread_key_create() : %m");
80 abort();
81 }
82
83 if (pthread_key_create(&MyConKey, NULL) != 0) { // TSD for sessions
84 syslog(LOG_CRIT, "sysdep: can't create TSD key: %m");
85 abort();
86 }
87
88 // Interript, hangup, and terminate signals should cause the server to shut down.
89 sigemptyset(&set);
90 sigaddset(&set, SIGINT);
91 sigaddset(&set, SIGHUP);
92 sigaddset(&set, SIGTERM);
93 sigprocmask(SIG_UNBLOCK, &set, NULL);
94
95 signal(SIGINT, signal_cleanup);
96 signal(SIGHUP, signal_cleanup);
97 signal(SIGTERM, signal_cleanup);
98
99 // Do not shut down the server on broken pipe signals, otherwise the
100 // whole Citadel service would come down whenever a single client
101 // socket breaks.
102 signal(SIGPIPE, SIG_IGN);
103}
104
105
106// This is a generic function to set up a master socket for listening on
107// a TCP port. The server shuts down if the bind fails. (IPv4/IPv6 version)
108//
109// ip_addr IP address to bind
110// port_number port number to bind
111// queue_len number of incoming connections to allow in the queue
112int ctdl_tcp_server(char *ip_addr, int port_number, int queue_len) {
113 struct protoent *p;
114 struct sockaddr_in6 sin6;
115 struct sockaddr_in sin4;
116 int s, i, b;
117 int ip_version = 6;
118
119 memset(&sin6, 0, sizeof(sin6));
120 memset(&sin4, 0, sizeof(sin4));
121 sin6.sin6_family = AF_INET6;
122 sin4.sin_family = AF_INET;
123
124 if ( (ip_addr == NULL) // any IPv6
125 || (IsEmptyStr(ip_addr))
126 || (!strcmp(ip_addr, "*"))
127 ) {
128 ip_version = 6;
129 sin6.sin6_addr = in6addr_any;
130 }
131 else if (!strcmp(ip_addr, "0.0.0.0")) // any IPv4
132 {
133 ip_version = 4;
134 sin4.sin_addr.s_addr = INADDR_ANY;
135 }
136 else if ((strchr(ip_addr, '.')) && (!strchr(ip_addr, ':'))) // specific IPv4
137 {
138 ip_version = 4;
139 if (inet_pton(AF_INET, ip_addr, &sin4.sin_addr) <= 0) {
140 syslog(LOG_ALERT, "tcpserver: inet_pton: %m");
141 return (-1);
142 }
143 }
144 else // specific IPv6
145 {
146 ip_version = 6;
147 if (inet_pton(AF_INET6, ip_addr, &sin6.sin6_addr) <= 0) {
148 syslog(LOG_ALERT, "tcpserver: inet_pton: %m");
149 return (-1);
150 }
151 }
152
153 if (port_number == 0) {
154 syslog(LOG_ALERT, "tcpserver: no port number was specified");
155 return (-1);
156 }
157 sin6.sin6_port = htons((u_short) port_number);
158 sin4.sin_port = htons((u_short) port_number);
159
160 p = getprotobyname("tcp");
161 if (p == NULL) {
162 syslog(LOG_ALERT, "tcpserver: getprotobyname: %m");
163 return (-1);
164 }
165
166 s = socket( ((ip_version == 6) ? PF_INET6 : PF_INET), SOCK_STREAM, (p->p_proto));
167 if (s < 0) {
168 syslog(LOG_ALERT, "tcpserver: socket: %m");
169 return (-1);
170 }
171 // Set some socket options that make sense.
172 i = 1;
173 setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
174
175 if (ip_version == 6) {
176 b = bind(s, (struct sockaddr *) &sin6, sizeof(sin6));
177 }
178 else {
179 b = bind(s, (struct sockaddr *) &sin4, sizeof(sin4));
180 }
181
182 if (b < 0) {
183 syslog(LOG_ALERT, "tcpserver: bind: %m");
184 return (-1);
185 }
186
187 fcntl(s, F_SETFL, O_NONBLOCK);
188
189 if (listen(s, ((queue_len >= 5) ? queue_len : 5) ) < 0) {
190 syslog(LOG_ALERT, "tcpserver: listen: %m");
191 return (-1);
192 }
193 return (s);
194}
195
196
197// Create a Unix domain socket and listen on it
198int ctdl_uds_server(char *sockpath, int queue_len) {
199 struct sockaddr_un addr;
200 int s;
201 int i;
202 int actual_queue_len;
203#ifdef HAVE_STRUCT_UCRED
204 int passcred = 1;
205#endif
206
207 actual_queue_len = queue_len;
208 if (actual_queue_len < 5) actual_queue_len = 5;
209
210 i = unlink(sockpath);
211 if ((i != 0) && (errno != ENOENT)) {
212 syslog(LOG_ERR, "udsserver: %m");
213 return(-1);
214 }
215
216 memset(&addr, 0, sizeof(addr));
217 addr.sun_family = AF_UNIX;
218 safestrncpy(addr.sun_path, sockpath, sizeof addr.sun_path);
219
220 s = socket(AF_UNIX, SOCK_STREAM, 0);
221 if (s < 0) {
222 syslog(LOG_ERR, "udsserver: socket: %m");
223 return(-1);
224 }
225
226 if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
227 syslog(LOG_ERR, "udsserver: bind: %m");
228 return(-1);
229 }
230
231 // set to nonblock - we need this for some obscure situations
232 if (fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
233 syslog(LOG_ERR, "udsserver: fcntl: %m");
234 close(s);
235 return(-1);
236 }
237
238 if (listen(s, actual_queue_len) < 0) {
239 syslog(LOG_ERR, "udsserver: listen: %m");
240 return(-1);
241 }
242
243#ifdef HAVE_STRUCT_UCRED
244 setsockopt(s, SOL_SOCKET, SO_PASSCRED, &passcred, sizeof(passcred));
245#endif
246
247 chmod(sockpath, S_ISGID|S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IWGRP|S_IXGRP|S_IROTH|S_IWOTH|S_IXOTH);
248 return(s);
249}
250
251
252// The following functions implement output buffering on operating systems which
253// support it (such as Linux and various BSD flavors).
254#ifndef HAVE_DARWIN
255#ifdef TCP_CORK
256# define HAVE_TCP_BUFFERING
257#else
258# ifdef TCP_NOPUSH
259# define HAVE_TCP_BUFFERING
260# define TCP_CORK TCP_NOPUSH
261# endif
262#endif // TCP_CORK
263#endif // HAVE_DARWIN
264
265static unsigned on = 1, off = 0;
266
267void buffer_output(void) {
268#ifdef HAVE_TCP_BUFFERING
269#ifdef HAVE_OPENSSL
270 if (!CC->redirect_ssl)
271#endif
272 setsockopt(CC->client_socket, IPPROTO_TCP, TCP_CORK, &on, 4);
273#endif
274}
275
276void unbuffer_output(void) {
277#ifdef HAVE_TCP_BUFFERING
278#ifdef HAVE_OPENSSL
279 if (!CC->redirect_ssl)
280#endif
281 setsockopt(CC->client_socket, IPPROTO_TCP, TCP_CORK, &off, 4);
282#endif
283}
284
285void flush_output(void) {
286#ifdef HAVE_TCP_BUFFERING
287 struct CitContext *CCC = CC;
288 setsockopt(CCC->client_socket, IPPROTO_TCP, TCP_CORK, &off, 4);
289 setsockopt(CCC->client_socket, IPPROTO_TCP, TCP_CORK, &on, 4);
290#endif
291}
292
293
294// close the client socket
295void client_close(void) {
296 CitContext *CCC = CC;
297
298 if (!CCC) return;
299 if (CCC->client_socket <= 0) return;
300 syslog(LOG_DEBUG, "sysdep: closing socket %d", CCC->client_socket);
301 close(CCC->client_socket);
302 CCC->client_socket = -1 ;
303}
304
305
306// Send binary data to the client.
307int client_write(const char *buf, int nbytes)
308{
309 int bytes_written = 0;
310 int retval;
311#ifndef HAVE_TCP_BUFFERING
312 int old_buffer_len = 0;
313#endif
314 fd_set wset;
315 CitContext *Ctx;
316 int fdflags;
317
318 if (nbytes < 1) return(0);
319
320 Ctx = CC;
321
322 if (Ctx->redirect_buffer != NULL) {
323 StrBufAppendBufPlain(Ctx->redirect_buffer,
324 buf, nbytes, 0);
325 return 0;
326 }
327
328#ifdef HAVE_OPENSSL
329 if (Ctx->redirect_ssl) {
330 client_write_ssl(buf, nbytes);
331 return 0;
332 }
333#endif
334 if (Ctx->client_socket == -1) return -1;
335
336 fdflags = fcntl(Ctx->client_socket, F_GETFL);
337
338 while ((bytes_written < nbytes) && (Ctx->client_socket != -1)){
339 if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
340 FD_ZERO(&wset);
341 FD_SET(Ctx->client_socket, &wset);
342 if (select(1, NULL, &wset, NULL, NULL) == -1) {
343 if (errno == EINTR)
344 {
345 syslog(LOG_DEBUG, "sysdep: client_write(%d bytes) select() interrupted.", nbytes-bytes_written);
347 CC->kill_me = KILLME_SELECT_INTERRUPTED;
348 return (-1);
349 } else {
350 // can't trust fd's and stuff so we need to re-create them
351 continue;
352 }
353 } else {
354 syslog(LOG_ERR, "sysdep: client_write(%d bytes) select failed: %m", nbytes - bytes_written);
355 client_close();
357 return -1;
358 }
359 }
360 }
361
362 retval = write(Ctx->client_socket, &buf[bytes_written], nbytes - bytes_written);
363 if (retval < 1) {
364 syslog(LOG_ERR, "sysdep: client_write(%d bytes) failed: %m", nbytes - bytes_written);
365 client_close();
367 return -1;
368 }
369 bytes_written = bytes_written + retval;
370 }
371 return 0;
372}
373
374void cputbuf(const StrBuf *Buf) {
375 client_write(ChrPtr(Buf), StrLength(Buf));
376}
377
378
379// Send formatted printable data to the client.
380// Implemented in terms of client_write() so it's technically not sysdep...
381void cprintf(const char *format, ...) {
382 va_list arg_ptr;
383 char buf[1024];
384
385 va_start(arg_ptr, format);
386 if (vsnprintf(buf, sizeof buf, format, arg_ptr) == -1)
387 buf[sizeof buf - 2] = '\n';
388 client_write(buf, strlen(buf));
389 va_end(arg_ptr);
390}
391
392
393// Read data from the client socket.
394//
395// sock socket fd to read from
396// buf buffer to read into
397// bytes number of bytes to read
398// timeout Number of seconds to wait before timing out
399//
400// Possible return values:
401// 1 Requested number of bytes has been read.
402// 0 Request timed out.
403// -1 Connection is broken, or other error.
404int client_read_blob(StrBuf *Target, int bytes, int timeout) {
405 CitContext *CCC=CC;
406 const char *Error;
407 int retval = 0;
408
409#ifdef HAVE_OPENSSL
410 if (CCC->redirect_ssl) {
411 retval = client_read_sslblob(Target, bytes, timeout);
412 if (retval < 0) {
413 syslog(LOG_ERR, "sysdep: client_read_blob() failed");
414 }
415 }
416 else
417#endif
418 {
419 retval = StrBufReadBLOBBuffered(Target,
420 CCC->RecvBuf.Buf,
421 &CCC->RecvBuf.ReadWritePointer,
422 &CCC->client_socket,
423 1,
424 bytes,
425 O_TERM,
426 &Error
427 );
428 if (retval < 0) {
429 syslog(LOG_ERR, "sysdep: client_read_blob() failed: %s", Error);
430 client_close();
431 return retval;
432 }
433 }
434 return retval;
435}
436
437
438// to make client_read_random_blob() more efficient, increase buffer size.
439// just use in greeting function, else your buffer may be flushed
441{
442 CitContext *CCC=CC;
443 FlushStrBuf(CCC->RecvBuf.Buf);
444 ReAdjustEmptyBuf(CCC->RecvBuf.Buf, N * SIZ, N * SIZ);
445}
446
447int client_read_random_blob(StrBuf *Target, int timeout)
448{
449 CitContext *CCC=CC;
450 int rc;
451
452 rc = client_read_blob(Target, 1, timeout);
453 if (rc > 0)
454 {
455 long len;
456 const char *pch;
457
458 len = StrLength(CCC->RecvBuf.Buf);
459 pch = ChrPtr(CCC->RecvBuf.Buf);
460
461 if (len > 0)
462 {
463 if (CCC->RecvBuf.ReadWritePointer != NULL) {
464 len -= CCC->RecvBuf.ReadWritePointer - pch;
465 pch = CCC->RecvBuf.ReadWritePointer;
466 }
467 StrBufAppendBufPlain(Target, pch, len, 0);
468 FlushStrBuf(CCC->RecvBuf.Buf);
469 CCC->RecvBuf.ReadWritePointer = NULL;
470 return StrLength(Target);
471 }
472 return rc;
473 }
474 else
475 return rc;
476}
477
478int client_read_to(char *buf, int bytes, int timeout)
479{
480 CitContext *CCC=CC;
481 int rc;
482
483 rc = client_read_blob(CCC->MigrateBuf, bytes, timeout);
484 if (rc < 0)
485 {
486 *buf = '\0';
487 return rc;
488 }
489 else
490 {
491 memcpy(buf,
492 ChrPtr(CCC->MigrateBuf),
493 StrLength(CCC->MigrateBuf) + 1);
494 FlushStrBuf(CCC->MigrateBuf);
495 return rc;
496 }
497}
498
499
501 if ((CCC->kill_me != 0) ||
502 ( (CCC->RecvBuf.ReadWritePointer == NULL) &&
503 (StrLength(CCC->RecvBuf.Buf) == 0) &&
504 (CCC->client_socket != -1)) )
505 return 0;
506 else
507 return 1;
508}
509
510
511// Read data from the client socket with default timeout.
512// (This is implemented in terms of client_read_to() and could be
513// justifiably moved out of sysdep.c)
514INLINE int client_read(char *buf, int bytes) {
515 return(client_read_to(buf, bytes, CtdlGetConfigInt("c_sleeping")));
516}
517
518int CtdlClientGetLine(StrBuf *Target) {
519 CitContext *CCC=CC;
520 const char *Error;
521 int rc;
522
523 FlushStrBuf(Target);
524#ifdef HAVE_OPENSSL
525 if (CCC->redirect_ssl) {
526 rc = client_readline_sslbuffer(Target, CCC->RecvBuf.Buf, &CCC->RecvBuf.ReadWritePointer, 1);
527 return rc;
528 }
529 else
530#endif
531 {
532 rc = StrBufTCP_read_buffered_line_fast(Target,
533 CCC->RecvBuf.Buf,
534 &CCC->RecvBuf.ReadWritePointer,
535 &CCC->client_socket,
536 5,
537 1,
538 &Error
539 );
540 return rc;
541 }
542}
543
544
545// Get a LF-terminated line of text from the client.
546// (This is implemented in terms of client_read() and could be
547// justifiably moved out of sysdep.c)
548int client_getln(char *buf, int bufsize) {
549 int i, retval;
550 CitContext *CCC=CC;
551 const char *pCh;
552
553 retval = CtdlClientGetLine(CCC->MigrateBuf);
554 if (retval < 0)
555 return(retval >= 0);
556
557
558 i = StrLength(CCC->MigrateBuf);
559 pCh = ChrPtr(CCC->MigrateBuf);
560 // Strip the trailing LF, and the trailing CR if present.
561 if (bufsize <= i)
562 i = bufsize - 1;
563 while ( (i > 0)
564 && ( (pCh[i - 1]==13)
565 || ( pCh[i - 1]==10)) ) {
566 i--;
567 }
568 memcpy(buf, pCh, i);
569 buf[i] = 0;
570
571 FlushStrBuf(CCC->MigrateBuf);
572 if (retval < 0) {
573 safestrncpy(&buf[i], "000", bufsize - i);
574 }
575 return(retval >= 0);
576}
577
578
579// Cleanup any contexts that are left lying around
580void close_masters(void) {
581 struct ServiceFunctionHook *serviceptr;
582 const char *Text;
583
584 // close all protocol master sockets
585 for (serviceptr = ServiceHookTable; serviceptr != NULL;
586 serviceptr = serviceptr->next ) {
587
588 if (serviceptr->tcp_port > 0) {
589 if (serviceptr->msock == -1) {
590 Text = "not closing again";
591 }
592 else {
593 Text = "Closing";
594 }
595 syslog(LOG_INFO, "sysdep: %s %d listener on port %d",
596 Text,
597 serviceptr->msock,
598 serviceptr->tcp_port
599 );
600 serviceptr->tcp_port = 0;
601 }
602
603 if (serviceptr->sockpath != NULL) {
604 if (serviceptr->msock == -1) {
605 Text = "not closing again";
606 }
607 else {
608 Text = "Closing";
609 }
610 syslog(LOG_INFO, "sysdep: %s %d listener on '%s'",
611 Text,
612 serviceptr->msock,
613 serviceptr->sockpath
614 );
615 }
616
617 if (serviceptr->msock != -1) {
618 close(serviceptr->msock);
619 serviceptr->msock = -1;
620 }
621
622 // If it's a Unix domain socket, remove the file.
623 if (serviceptr->sockpath != NULL) {
624 unlink(serviceptr->sockpath);
625 serviceptr->sockpath = NULL;
626 }
627 }
628}
629
630
631// The system-dependent part of master_cleanup() - close the master socket.
635#ifdef HAVE_OPENSSL
636 destruct_ssl();
637#endif
638}
639
640
641
643void graceful_shutdown(int signum) {
644 kill(current_child, signum);
645 unlink(file_pid_file);
646 exit(0);
647}
648
649int nFireUps = 0;
651pid_t ForkedPid = 1;
652
653// Start running as a daemon.
654void start_daemon(int unused) {
655 int status = 0;
656 pid_t child = 0;
657 FILE *fp;
658 int do_restart = 0;
659 current_child = 0;
660
661 // Close stdin/stdout/stderr and replace them with /dev/null.
662 // We don't just call close() because we don't want these fd's
663 // to be reused for other files.
664 child = fork();
665 if (child != 0) {
666 exit(0);
667 }
668
669 signal(SIGHUP, SIG_IGN);
670 signal(SIGINT, SIG_IGN);
671 signal(SIGQUIT, SIG_IGN);
672
673 setsid();
674 umask(0);
675 if ( (freopen("/dev/null", "r", stdin) != stdin) ||
676 (freopen("/dev/null", "w", stdout) != stdout) ||
677 (freopen("/dev/null", "w", stderr) != stderr)
678 ) {
679 syslog(LOG_ERR, "sysdep: unable to reopen stdio: %m");
680 }
681
682 do {
683 current_child = fork();
684 signal(SIGTERM, graceful_shutdown);
685 if (current_child < 0) {
686 perror("fork");
687 exit(errno);
688 }
689 else if (current_child == 0) {
690 return; // continue starting citadel.
691 }
692 else {
693 fp = fopen(file_pid_file, "w");
694 if (fp != NULL) {
695 fprintf(fp, ""F_PID_T"\n", getpid());
696 fclose(fp);
697 }
698 waitpid(current_child, &status, 0);
699 }
701
702 // Exit code 0 means the watcher should exit
703 if (WIFEXITED(status) && (WEXITSTATUS(status) == CTDLEXIT_SHUTDOWN)) {
704 do_restart = 0;
705 }
706
707 // Exit code 101-109 means the watcher should exit
708 else if (WIFEXITED(status) && (WEXITSTATUS(status) >= 101) && (WEXITSTATUS(status) <= 109)) {
709 do_restart = 0;
710 }
711
712 // Any other exit code, or no exit code, means we should restart.
713 else {
714 do_restart = 1;
715 nFireUps++;
717 }
718
719 } while (do_restart);
720
721 unlink(file_pid_file);
722 exit(WEXITSTATUS(status));
723}
724
725
726void checkcrash(void) {
728 StrBuf *CrashMail;
729 CrashMail = NewStrBuf();
730 syslog(LOG_ALERT, "sysdep: posting crash message");
731 StrBufPrintf(CrashMail,
732 " \n"
733 " The Citadel server process (citserver) terminated unexpectedly."
734 "\n \n"
735 " This could be the result of a bug in the server program, or some external "
736 "factor.\n \n"
737 " You can obtain more information about this by enabling core dumps.\n \n"
738 " For more information, please see:\n \n"
739 " http://citadel.org/doku.php?id=faq:mastering_your_os:gdb#how.do.i.make.my.system.produce.core-files"
740 "\n \n"
741
742 " If you have already done this, the core dump is likely to be found at %score.%d\n"
743 ,
745 CtdlAideMessage(ChrPtr(CrashMail), "Citadel server process terminated unexpectedly");
746 FreeStrBuf(&CrashMail);
747 }
748}
749
750
751// Generic routine to convert a login name to a full name (gecos)
752// Returns nonzero if a conversion took place
753int convert_login(char NameToConvert[]) {
754 struct passwd *pw;
755 unsigned int a;
756
757 pw = getpwnam(NameToConvert);
758 if (pw == NULL) {
759 return(0);
760 }
761 else {
762 strcpy(NameToConvert, pw->pw_gecos);
763 for (a=0; a<strlen(NameToConvert); ++a) {
764 if (NameToConvert[a] == ',') NameToConvert[a] = 0;
765 }
766 return(1);
767 }
768}
769
770
771void HuntBadSession(void) {
772 int highest;
773 CitContext *ptr;
774 fd_set readfds;
775 struct timeval tv;
776 struct ServiceFunctionHook *serviceptr;
777
778 // Next, add all of the client sockets
780 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
781 if ((ptr->state == CON_SYS) && (ptr->client_socket == 0))
782 continue;
783 // Initialize the fdset.
784 FD_ZERO(&readfds);
785 highest = 0;
786 tv.tv_sec = 0; // wake up every second if no input
787 tv.tv_usec = 0;
788
789 // Don't select on dead sessions, only truly idle ones
790 if ( (ptr->state == CON_IDLE)
791 && (ptr->kill_me == 0)
792 && (ptr->client_socket > 0)
793 ) {
794 FD_SET(ptr->client_socket, &readfds);
795 if (ptr->client_socket > highest)
796 highest = ptr->client_socket;
797
798 if ((select(highest + 1, &readfds, NULL, NULL, &tv) < 0) && (errno == EBADF))
799 {
800 // Gotcha!
801 syslog(LOG_ERR,
802 "sysdep: killing session CC[%d] bad FD: [%d] User[%s] Host[%s:%s]",
803 ptr->cs_pid,
804 ptr->client_socket,
805 ptr->curr_user,
806 ptr->cs_host,
807 ptr->cs_addr
808 );
809 ptr->kill_me = 1;
810 ptr->client_socket = -1;
811 break;
812 }
813 }
814 }
816
817 // First, add the various master sockets to the fdset.
818 for (serviceptr = ServiceHookTable; serviceptr != NULL; serviceptr = serviceptr->next ) {
819
820 // Initialize the fdset.
821 highest = 0;
822 tv.tv_sec = 0; // wake up every second if no input
823 tv.tv_usec = 0;
824
825 FD_SET(serviceptr->msock, &readfds);
826 if (serviceptr->msock > highest) {
827 highest = serviceptr->msock;
828 }
829 if ((select(highest + 1, &readfds, NULL, NULL, &tv) < 0) &&
830 (errno == EBADF))
831 {
832 // Gotcha! server socket dead? commit suicide!
833 syslog(LOG_ERR, "sysdep: found bad FD: %d and its a server socket! Shutting Down!", serviceptr->msock);
835 break;
836 }
837 }
838}
839
840
841// This loop just keeps going and going and going...
842void *worker_thread(void *blah) {
843 int highest;
844 CitContext *ptr;
845 CitContext *bind_me = NULL;
846 fd_set readfds;
847 int retval = 0;
848 struct timeval tv;
849 int force_purge = 0;
850 struct ServiceFunctionHook *serviceptr;
851 int ssock; // Descriptor for client socket
852 CitContext *con = NULL; // Temporary context pointer
853 int i;
854
855 pthread_mutex_lock(&ThreadCountMutex);
856 ++num_workers;
857 pthread_mutex_unlock(&ThreadCountMutex);
858
859 while (!server_shutting_down) {
860
861 // make doubly sure we're not holding any stale db handles which might cause a deadlock
863do_select: force_purge = 0;
864 bind_me = NULL; // Which session shall we handle?
865
866 // Initialize the fdset
867 FD_ZERO(&readfds);
868 highest = 0;
869
870 // First, add the various master sockets to the fdset.
871 for (serviceptr = ServiceHookTable; serviceptr != NULL; serviceptr = serviceptr->next ) {
872 FD_SET(serviceptr->msock, &readfds);
873 if (serviceptr->msock > highest) {
874 highest = serviceptr->msock;
875 }
876 }
877
878 // Next, add all of the client sockets.
880 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
881 if ((ptr->state == CON_SYS) && (ptr->client_socket == 0))
882 continue;
883
884 // Don't select on dead sessions, only truly idle ones
885 if ( (ptr->state == CON_IDLE)
886 && (ptr->kill_me == 0)
887 && (ptr->client_socket > 0)
888 ) {
889 FD_SET(ptr->client_socket, &readfds);
890 if (ptr->client_socket > highest)
891 highest = ptr->client_socket;
892 }
893 if ((bind_me == NULL) && (ptr->state == CON_READY)) {
894 bind_me = ptr;
895 ptr->state = CON_EXECUTING;
896 break;
897 }
898 if ((bind_me == NULL) && (ptr->state == CON_GREETING)) {
899 bind_me = ptr;
900 ptr->state = CON_STARTING;
901 break;
902 }
903 }
905
906 if (bind_me) {
907 goto SKIP_SELECT;
908 }
909
910 // If we got this far, it means that there are no sessions
911 // which a previous thread marked for attention, so we go
912 // ahead and get ready to select().
913
915 tv.tv_sec = 1; // wake up every second if no input
916 tv.tv_usec = 0;
917 retval = select(highest + 1, &readfds, NULL, NULL, &tv);
918 }
919 else {
920 --num_workers;
921 return NULL;
922 }
923
924 // Now figure out who made this select() unblock.
925 // First, check for an error or exit condition.
926 if (retval < 0) {
927 if (errno == EBADF) {
928 syslog(LOG_ERR, "sysdep: select() failed: %m");
930 goto do_select;
931 }
932 if (errno != EINTR) {
933 syslog(LOG_ERR, "sysdep: exiting: %m");
935 continue;
936 } else {
938 --num_workers;
939 return(NULL);
940 }
941 goto do_select;
942 }
943 }
944 else if (retval == 0) {
946 --num_workers;
947 return(NULL);
948 }
949 }
950
951 // Next, check to see if it's a new client connecting on a master socket.
952
953 else if ((retval > 0) && (!server_shutting_down)) for (serviceptr = ServiceHookTable; serviceptr != NULL; serviceptr = serviceptr->next) {
954
955 if (FD_ISSET(serviceptr->msock, &readfds)) {
956 ssock = accept(serviceptr->msock, NULL, 0);
957 if (ssock >= 0) {
958 syslog(LOG_DEBUG, "sysdep: new client socket %d", ssock);
959
960 // The master socket is non-blocking but the client
961 // sockets need to be blocking, otherwise certain
962 // operations barf on FreeBSD. Not a fatal error.
963 if (fcntl(ssock, F_SETFL, 0) < 0) {
964 syslog(LOG_ERR, "sysdep: Can't set socket to blocking: %m");
965 }
966
967 // New context will be created already
968 // set up in the CON_EXECUTING state.
969 con = CreateNewContext();
970
971 // Assign our new socket number to it.
972 con->tcp_port = serviceptr->tcp_port;
973 con->client_socket = ssock;
974 con->h_command_function = serviceptr->h_command_function;
975 con->h_async_function = serviceptr->h_async_function;
976 con->h_greeting_function = serviceptr->h_greeting_function;
977 con->ServiceName = serviceptr->ServiceName;
978
979 // Connections on a local client are always from the same host
980 if (serviceptr->sockpath != NULL) {
981 con->is_local_client = 1;
982 }
983
984 // Set the SO_REUSEADDR socket option
985 i = 1;
986 setsockopt(ssock, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
987 con->state = CON_GREETING;
988 retval--;
989 if (retval == 0)
990 break;
991 }
992 }
993 }
994
995 // It must be a client socket. Find a context that has data
996 // waiting on its socket *and* is in the CON_IDLE state. Any
997 // active sockets other than our chosen one are marked as
998 // CON_READY so the next thread that comes around can just bind
999 // to one without having to select() again.
1001 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
1002 int checkfd = ptr->client_socket;
1003 if ((checkfd != -1) && (ptr->state == CON_IDLE) ){
1004 if (FD_ISSET(checkfd, &readfds)) {
1005 ptr->input_waiting = 1;
1006 if (!bind_me) {
1007 bind_me = ptr; // I choose you!
1008 bind_me->state = CON_EXECUTING;
1009 }
1010 else {
1011 ptr->state = CON_READY;
1012 }
1013 } else if ((ptr->is_async) && (ptr->async_waiting) && (ptr->h_async_function)) {
1014 if (!bind_me) {
1015 bind_me = ptr; // I choose you!
1016 bind_me->state = CON_EXECUTING;
1017 }
1018 else {
1019 ptr->state = CON_READY;
1020 }
1021 }
1022 }
1023 }
1025
1026SKIP_SELECT:
1027 // We're bound to a session
1028 pthread_mutex_lock(&ThreadCountMutex);
1030 pthread_mutex_unlock(&ThreadCountMutex);
1031
1032 if (bind_me != NULL) {
1033 become_session(bind_me);
1034
1035 if (bind_me->state == CON_STARTING) {
1036 bind_me->state = CON_EXECUTING;
1037 begin_session(bind_me);
1038 bind_me->h_greeting_function();
1039 }
1040 // If the client has sent a command, execute it.
1041 if (CC->input_waiting) {
1042 CC->h_command_function();
1043
1044 while (HaveMoreLinesWaiting(CC))
1045 CC->h_command_function();
1046
1047 CC->input_waiting = 0;
1048 }
1049
1050 // If there are asynchronous messages waiting and the client supports it, do those now
1051 if ((CC->is_async) && (CC->async_waiting) && (CC->h_async_function != NULL)) {
1052 CC->h_async_function();
1053 CC->async_waiting = 0;
1054 }
1055
1056 force_purge = CC->kill_me;
1057 become_session(NULL);
1058 bind_me->state = CON_IDLE;
1059 }
1060
1061 dead_session_purge(force_purge);
1063
1064 pthread_mutex_lock(&ThreadCountMutex);
1066 if ((active_workers + CtdlGetConfigInt("c_min_workers") < num_workers) &&
1067 (num_workers > CtdlGetConfigInt("c_min_workers")))
1068 {
1069 num_workers--;
1070 pthread_mutex_unlock(&ThreadCountMutex);
1071 return (NULL);
1072 }
1073 pthread_mutex_unlock(&ThreadCountMutex);
1074 }
1075
1076 // If control reaches this point, the server is shutting down
1077 pthread_mutex_lock(&ThreadCountMutex);
1078 --num_workers;
1079 pthread_mutex_unlock(&ThreadCountMutex);
1080 return(NULL);
1081}
1082
1083
1084// SyslogFacility()
1085// Translate text facility name to syslog.h defined value.
1086int SyslogFacility(char *name)
1087{
1088 int i;
1089 struct
1090 {
1091 int facility;
1092 char *name;
1093 } facTbl[] =
1094 {
1095 { LOG_KERN, "kern" },
1096 { LOG_USER, "user" },
1097 { LOG_MAIL, "mail" },
1098 { LOG_DAEMON, "daemon" },
1099 { LOG_AUTH, "auth" },
1100 { LOG_SYSLOG, "syslog" },
1101 { LOG_LPR, "lpr" },
1102 { LOG_NEWS, "news" },
1103 { LOG_UUCP, "uucp" },
1104 { LOG_LOCAL0, "local0" },
1105 { LOG_LOCAL1, "local1" },
1106 { LOG_LOCAL2, "local2" },
1107 { LOG_LOCAL3, "local3" },
1108 { LOG_LOCAL4, "local4" },
1109 { LOG_LOCAL5, "local5" },
1110 { LOG_LOCAL6, "local6" },
1111 { LOG_LOCAL7, "local7" },
1112 { 0, NULL }
1113 };
1114 for(i = 0; facTbl[i].name != NULL; i++) {
1115 if(!strcasecmp(name, facTbl[i].name))
1116 return facTbl[i].facility;
1117 }
1118 return LOG_DAEMON;
1119}
#define file_pid_file
Definition: citadel_dirs.h:31
#define ctdl_run_dir
Definition: citadel_dirs.h:17
void timeout(int signum)
Definition: citmail.c:41
void begin_session(struct CitContext *con)
Definition: context.c:471
int CtdlGetConfigInt(char *key)
Definition: config.c:426
CitContext * ContextList
Definition: context.c:22
CitContext * CreateNewContext(void)
Definition: context.c:336
pthread_key_t MyConKey
Definition: context.c:20
void dead_session_purge(int force)
Definition: context.c:631
void context_cleanup(void)
Definition: context.c:592
#define CC
Definition: context.h:140
static void become_session(CitContext *which_con)
Definition: context.h:175
@ CON_READY
Definition: context.h:26
@ CON_SYS
Definition: context.h:28
@ CON_IDLE
Definition: context.h:23
@ CON_EXECUTING
Definition: context.h:27
@ CON_GREETING
Definition: context.h:24
@ CON_STARTING
Definition: context.h:25
#define CtdlAideMessage(TEXT, SUBJECT)
Definition: ctdl_module.h:58
void cdb_check_handles(void)
Definition: database.c:137
void do_housekeeping(void)
Definition: housekeeping.c:98
ServiceFunctionHook * ServiceHookTable
#define INLINE
Definition: server.h:21
#define CTDLEXIT_SHUTDOWN
Definition: server.h:67
@ KILLME_SELECT_INTERRUPTED
Definition: server.h:95
@ KILLME_SELECT_FAILED
Definition: server.h:96
@ KILLME_WRITE_FAILED
Definition: server.h:97
@ S_SESSION_TABLE
Definition: server.h:137
int vsnprintf(char *buf, size_t max, const char *fmt, va_list argp)
Definition: snprintf.c:48
int cs_pid
Definition: context.h:44
StrBuf * MigrateBuf
Definition: context.h:56
long tcp_port
Definition: context.h:126
int is_async
Definition: context.h:78
const char * ServiceName
Definition: context.h:125
CitContext * next
Definition: context.h:42
char curr_user[64]
Definition: context.h:69
char cs_addr[64]
Definition: context.h:91
int kill_me
Definition: context.h:50
CCState state
Definition: context.h:49
void(* h_greeting_function)(void)
Definition: context.h:132
int is_local_client
Definition: context.h:60
void(* h_command_function)(void)
Definition: context.h:130
StrBuf * redirect_buffer
Definition: context.h:62
int async_waiting
Definition: context.h:79
char cs_host[64]
Definition: context.h:90
void(* h_async_function)(void)
Definition: context.h:131
int client_socket
Definition: context.h:59
int input_waiting
Definition: context.h:80
IOBuffer RecvBuf
Definition: context.h:53
void(* h_greeting_function)(void)
void(* h_async_function)(void)
void(* h_command_function)(void)
const char * ServiceName
ServiceFunctionHook * next
#define SIZ
Definition: sysconfig.h:33
pid_t ForkedPid
Definition: sysdep.c:651
int SyslogFacility(char *name)
Definition: sysdep.c:1086
int CtdlClientGetLine(StrBuf *Target)
Definition: sysdep.c:518
void cprintf(const char *format,...)
Definition: sysdep.c:381
int nFireUpsNonRestart
Definition: sysdep.c:650
int ctdl_tcp_server(char *ip_addr, int port_number, int queue_len)
Definition: sysdep.c:112
int client_read_to(char *buf, int bytes, int timeout)
Definition: sysdep.c:478
void close_masters(void)
Definition: sysdep.c:580
void sysdep_master_cleanup(void)
Definition: sysdep.c:632
int client_read_random_blob(StrBuf *Target, int timeout)
Definition: sysdep.c:447
int client_getln(char *buf, int bufsize)
Definition: sysdep.c:548
int client_write(const char *buf, int nbytes)
Definition: sysdep.c:307
void flush_output(void)
Definition: sysdep.c:285
int nFireUps
Definition: sysdep.c:649
void client_close(void)
Definition: sysdep.c:295
volatile int restart_server
Definition: sysdep.c:47
void buffer_output(void)
Definition: sysdep.c:267
void checkcrash(void)
Definition: sysdep.c:726
volatile int exit_signal
Definition: sysdep.c:45
static RETSIGTYPE signal_cleanup(int signum)
Definition: sysdep.c:51
void client_set_inbound_buf(long N)
Definition: sysdep.c:440
int client_read_blob(StrBuf *Target, int bytes, int timeout)
Definition: sysdep.c:404
int client_read(char *buf, int bytes)
Definition: sysdep.c:514
void * worker_thread(void *blah)
Definition: sysdep.c:842
void graceful_shutdown(int signum)
Definition: sysdep.c:643
static unsigned on
Definition: sysdep.c:265
static unsigned off
Definition: sysdep.c:265
int HaveMoreLinesWaiting(CitContext *CCC)
Definition: sysdep.c:500
volatile int shutdown_and_halt
Definition: sysdep.c:46
void unbuffer_output(void)
Definition: sysdep.c:276
volatile int running_as_daemon
Definition: sysdep.c:48
int convert_login(char NameToConvert[])
Definition: sysdep.c:753
void start_daemon(int unused)
Definition: sysdep.c:654
int ctdl_uds_server(char *sockpath, int queue_len)
Definition: sysdep.c:198
pid_t current_child
Definition: sysdep.c:642
void HuntBadSession(void)
Definition: sysdep.c:771
void cputbuf(const StrBuf *Buf)
Definition: sysdep.c:374
void init_sysdep(void)
Definition: sysdep.c:59
void begin_critical_section(int which_one)
Definition: threads.c:67
pthread_key_t ThreadKey
Definition: threads.c:28
void end_critical_section(int which_one)
Definition: threads.c:85
pthread_mutex_t ThreadCountMutex
Definition: threads.c:32
int active_workers
Definition: threads.c:27
int server_shutting_down
Definition: threads.c:31
int num_workers
Definition: threads.c:26