a0ba89b2c71e3144ee2c5e59279f224bc48e7011
[citadel.git] / citadel / sysdep.c
1 /*
2  * $Id$
3  *
4  * Citadel "system dependent" stuff.
5  * See COPYING for copyright information.
6  *
7  * Here's where we (hopefully) have most parts of the Citadel server that
8  * would need to be altered to run the server in a non-POSIX environment.
9  * 
10  * If we ever port to a different platform and either have multiple
11  * variants of this file or simply load it up with #ifdefs.
12  *
13  */
14
15 #include "sysdep.h"
16 #include <stdlib.h>
17 #include <unistd.h>
18 #include <stdio.h>
19 #include <fcntl.h>
20 #include <ctype.h>
21 #include <signal.h>
22 #include <sys/types.h>
23 #include <sys/stat.h>
24 #include <sys/wait.h>
25 #include <sys/socket.h>
26 #include <syslog.h>
27 #include <sys/syslog.h>
28
29 #if TIME_WITH_SYS_TIME
30 # include <sys/time.h>
31 # include <time.h>
32 #else
33 # if HAVE_SYS_TIME_H
34 #  include <sys/time.h>
35 # else
36 #  include <time.h>
37 # endif
38 #endif
39
40 #include <limits.h>
41 #include <sys/resource.h>
42 #include <netinet/in.h>
43 #include <netinet/tcp.h>
44 #include <arpa/inet.h>
45 #include <netdb.h>
46 #include <sys/un.h>
47 #include <string.h>
48 #include <pwd.h>
49 #include <errno.h>
50 #include <stdarg.h>
51 #include <grp.h>
52 #include <libcitadel.h>
53 #include "citadel.h"
54 #include "server.h"
55 #include "sysdep_decls.h"
56 #include "citserver.h"
57 #include "support.h"
58 #include "config.h"
59 #include "database.h"
60 #include "housekeeping.h"
61 #include "modules/crypto/serv_crypto.h" /* Needed for init_ssl, client_write_ssl, client_read_ssl, destruct_ssl */
62 #include "ecrash.h"
63 #include "context.h"
64
65 #ifdef HAVE_SYS_SELECT_H
66 #include <sys/select.h>
67 #endif
68
69 #ifndef HAVE_SNPRINTF
70 #include "snprintf.h"
71 #endif
72
73 #include "ctdl_module.h"
74 #include "threads.h"
75 #include "user_ops.h"
76 #include "control.h"
77
78
79 #ifdef DEBUG_MEMORY_LEAKS
80 struct igheap {
81         struct igheap *next;
82         char file[32];
83         int line;
84         void *block;
85 };
86
87 struct igheap *igheap = NULL;
88 #endif
89
90
91 int verbosity = DEFAULT_VERBOSITY;              /* Logging level */
92
93 int syslog_facility = LOG_DAEMON;
94 int enable_syslog = 0;
95
96
97 /*
98  * CtdlLogPrintf()  ...   Write logging information
99  */
100 void CtdlLogPrintf(enum LogLevel loglevel, const char *format, ...) {   
101         va_list arg_ptr;
102         va_start(arg_ptr, format);
103         vCtdlLogPrintf(loglevel, format, arg_ptr);
104         va_end(arg_ptr);
105 }
106
107 void vCtdlLogPrintf(enum LogLevel loglevel, const char *format, va_list arg_ptr)
108 {
109         char buf[SIZ], buf2[SIZ];
110
111         if (enable_syslog) {
112                 vsyslog((syslog_facility | loglevel), format, arg_ptr);
113         }
114
115         /* stderr output code */
116         if (enable_syslog || running_as_daemon) return;
117
118         /* if we run in forground and syslog is disabled, log to terminal */
119         if (loglevel <= verbosity) { 
120                 struct timeval tv;
121                 struct tm tim;
122                 time_t unixtime;
123                 CitContext *CCC = CC;
124
125                 gettimeofday(&tv, NULL);
126                 /* Promote to time_t; types differ on some OSes (like darwin) */
127                 unixtime = tv.tv_sec;
128                 localtime_r(&unixtime, &tim);
129                 if ((CCC != NULL) && (CCC->cs_pid != 0)) {
130                         sprintf(buf,
131                                 "%04d/%02d/%02d %2d:%02d:%02d.%06ld [%3d] ",
132                                 tim.tm_year + 1900, tim.tm_mon + 1,
133                                 tim.tm_mday, tim.tm_hour, tim.tm_min,
134                                 tim.tm_sec, (long)tv.tv_usec,
135                                 CCC->cs_pid);
136                 } else {
137                         sprintf(buf,
138                                 "%04d/%02d/%02d %2d:%02d:%02d.%06ld ",
139                                 tim.tm_year + 1900, tim.tm_mon + 1,
140                                 tim.tm_mday, tim.tm_hour, tim.tm_min,
141                                 tim.tm_sec, (long)tv.tv_usec);
142                 }
143                 vsnprintf(buf2, SIZ, format, arg_ptr);   
144
145                 fprintf(stderr, "%s%s", buf, buf2);
146                 fflush(stderr);
147         }
148 }   
149
150
151
152 /*
153  * Signal handler to shut down the server.
154  */
155
156 volatile int exit_signal = 0;
157 volatile int shutdown_and_halt = 0;
158 volatile int restart_server = 0;
159 volatile int running_as_daemon = 0;
160
161 static RETSIGTYPE signal_cleanup(int signum) {
162
163         if (CT)
164                 CT->signal = signum;
165         else
166         {
167                 CtdlLogPrintf(CTDL_DEBUG, "Caught signal %d; shutting down.\n", signum);
168                 exit_signal = signum;
169         }
170 }
171
172
173
174 /*
175  * Some initialization stuff...
176  */
177 void init_sysdep(void) {
178         sigset_t set;
179
180         /* Avoid vulnerabilities related to FD_SETSIZE if we can. */
181 #ifdef FD_SETSIZE
182 #ifdef RLIMIT_NOFILE
183         struct rlimit rl;
184         getrlimit(RLIMIT_NOFILE, &rl);
185         rl.rlim_cur = FD_SETSIZE;
186         rl.rlim_max = FD_SETSIZE;
187         setrlimit(RLIMIT_NOFILE, &rl);
188 #endif
189 #endif
190
191         /* If we've got OpenSSL, we're going to use it. */
192 #ifdef HAVE_OPENSSL
193         init_ssl();
194 #endif
195
196         /*
197          * Set up a place to put thread-specific data.
198          * We only need a single pointer per thread - it points to the
199          * CitContext structure (in the ContextList linked list) of the
200          * session to which the calling thread is currently bound.
201          */
202         if (citthread_key_create(&MyConKey, NULL) != 0) {
203                 CtdlLogPrintf(CTDL_CRIT, "Can't create TSD key: %s\n",
204                         strerror(errno));
205         }
206
207         /*
208          * The action for unexpected signals and exceptions should be to
209          * call signal_cleanup() to gracefully shut down the server.
210          */
211         sigemptyset(&set);
212         sigaddset(&set, SIGINT);
213         sigaddset(&set, SIGQUIT);
214         sigaddset(&set, SIGHUP);
215         sigaddset(&set, SIGTERM);
216         // sigaddset(&set, SIGSEGV);    commented out because
217         // sigaddset(&set, SIGILL);     we want core dumps
218         // sigaddset(&set, SIGBUS);
219         sigprocmask(SIG_UNBLOCK, &set, NULL);
220
221         signal(SIGINT, signal_cleanup);
222         signal(SIGQUIT, signal_cleanup);
223         signal(SIGHUP, signal_cleanup);
224         signal(SIGTERM, signal_cleanup);
225         // signal(SIGSEGV, signal_cleanup);     commented out because
226         // signal(SIGILL, signal_cleanup);      we want core dumps
227         // signal(SIGBUS, signal_cleanup);
228
229         /*
230          * Do not shut down the server on broken pipe signals, otherwise the
231          * whole Citadel service would come down whenever a single client
232          * socket breaks.
233          */
234         signal(SIGPIPE, SIG_IGN);
235 }
236
237
238
239
240 /*
241  * This is a generic function to set up a master socket for listening on
242  * a TCP port.  The server shuts down if the bind fails.
243  *
244  */
245 int ig_tcp_server(char *ip_addr, int port_number, int queue_len, char **errormessage)
246 {
247         struct sockaddr_in sin;
248         int s, i;
249         int actual_queue_len;
250
251         actual_queue_len = queue_len;
252         if (actual_queue_len < 5) actual_queue_len = 5;
253
254         memset(&sin, 0, sizeof(sin));
255         sin.sin_family = AF_INET;
256         sin.sin_port = htons((u_short)port_number);
257         if (ip_addr == NULL) {
258                 sin.sin_addr.s_addr = INADDR_ANY;
259         }
260         else {
261                 sin.sin_addr.s_addr = inet_addr(ip_addr);
262         }
263                                                                                 
264         if (sin.sin_addr.s_addr == !INADDR_ANY) {
265                 sin.sin_addr.s_addr = INADDR_ANY;
266         }
267
268         s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
269
270         if (s < 0) {
271                 *errormessage = (char*) malloc(SIZ + 1);
272                 snprintf(*errormessage, SIZ, 
273                                  "citserver: Can't create a socket: %s",
274                                  strerror(errno));
275                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
276                 return(-1);
277         }
278
279         i = 1;
280         setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &i, sizeof(i));
281
282         if (bind(s, (struct sockaddr *)&sin, sizeof(sin)) < 0) {
283                 *errormessage = (char*) malloc(SIZ + 1);
284                 snprintf(*errormessage, SIZ, 
285                                  "citserver: Can't bind: %s",
286                                  strerror(errno));
287                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
288                 close(s);
289                 return(-1);
290         }
291
292         /* set to nonblock - we need this for some obscure situations */
293         if (fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
294                 *errormessage = (char*) malloc(SIZ + 1);
295                 snprintf(*errormessage, SIZ, 
296                                  "citserver: Can't set socket to non-blocking: %s",
297                                  strerror(errno));
298                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
299                 close(s);
300                 return(-1);
301         }
302
303         if (listen(s, actual_queue_len) < 0) {
304                 *errormessage = (char*) malloc(SIZ + 1);
305                 snprintf(*errormessage, SIZ, 
306                                  "citserver: Can't listen: %s",
307                                  strerror(errno));
308                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
309                 close(s);
310                 return(-1);
311         }
312
313         return(s);
314 }
315
316
317
318 /*
319  * Create a Unix domain socket and listen on it
320  */
321 int ig_uds_server(char *sockpath, int queue_len, char **errormessage)
322 {
323         struct sockaddr_un addr;
324         int s;
325         int i;
326         int actual_queue_len;
327 #ifdef HAVE_STRUCT_UCRED
328         int passcred = 1;
329 #endif
330
331         actual_queue_len = queue_len;
332         if (actual_queue_len < 5) actual_queue_len = 5;
333
334         i = unlink(sockpath);
335         if ((i != 0) && (errno != ENOENT)) {
336                 *errormessage = (char*) malloc(SIZ + 1);
337                 snprintf(*errormessage, SIZ, "citserver: can't unlink %s: %s",
338                         sockpath, strerror(errno));
339                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
340                 return(-1);
341         }
342
343         memset(&addr, 0, sizeof(addr));
344         addr.sun_family = AF_UNIX;
345         safestrncpy(addr.sun_path, sockpath, sizeof addr.sun_path);
346
347         s = socket(AF_UNIX, SOCK_STREAM, 0);
348         if (s < 0) {
349                 *errormessage = (char*) malloc(SIZ + 1);
350                 snprintf(*errormessage, SIZ, 
351                          "citserver: Can't create a socket: %s",
352                          strerror(errno));
353                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
354                 return(-1);
355         }
356
357         if (bind(s, (struct sockaddr *)&addr, sizeof(addr)) < 0) {
358                 *errormessage = (char*) malloc(SIZ + 1);
359                 snprintf(*errormessage, SIZ, 
360                          "citserver: Can't bind: %s",
361                          strerror(errno));
362                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
363                 return(-1);
364         }
365
366         /* set to nonblock - we need this for some obscure situations */
367         if (fcntl(s, F_SETFL, O_NONBLOCK) < 0) {
368                 *errormessage = (char*) malloc(SIZ + 1);
369                 snprintf(*errormessage, SIZ, 
370                          "citserver: Can't set socket to non-blocking: %s",
371                          strerror(errno));
372                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
373                 close(s);
374                 return(-1);
375         }
376
377         if (listen(s, actual_queue_len) < 0) {
378                 *errormessage = (char*) malloc(SIZ + 1);
379                 snprintf(*errormessage, SIZ, 
380                          "citserver: Can't listen: %s",
381                          strerror(errno));
382                 CtdlLogPrintf(CTDL_EMERG, "%s\n", *errormessage);
383                 return(-1);
384         }
385
386 #ifdef HAVE_STRUCT_UCRED
387         setsockopt(s, SOL_SOCKET, SO_PASSCRED, &passcred, sizeof(passcred));
388 #endif
389
390         chmod(sockpath, S_ISGID|S_IRUSR|S_IWUSR|S_IXUSR|S_IRGRP|S_IWGRP|S_IXGRP|S_IROTH|S_IWOTH|S_IXOTH);
391         return(s);
392 }
393
394
395
396 /*
397  * The following functions implement output buffering on operating systems which
398  * support it (such as Linux and various BSD flavors).
399  */
400 #ifndef HAVE_DARWIN
401 #ifdef TCP_CORK
402 #       define HAVE_TCP_BUFFERING
403 #else
404 #       ifdef TCP_NOPUSH
405 #               define HAVE_TCP_BUFFERING
406 #               define TCP_CORK TCP_NOPUSH
407 #       endif
408 #endif /* TCP_CORK */
409 #endif /* HAVE_DARWIN */
410
411 static unsigned on = 1, off = 0;
412
413 void buffer_output(void) {
414 #ifdef HAVE_TCP_BUFFERING
415 #ifdef HAVE_OPENSSL
416         if (!CC->redirect_ssl)
417 #endif
418                 setsockopt(CC->client_socket, IPPROTO_TCP, TCP_CORK, &on, 4);
419 #endif
420 }
421
422 void unbuffer_output(void) {
423 #ifdef HAVE_TCP_BUFFERING
424 #ifdef HAVE_OPENSSL
425         if (!CC->redirect_ssl)
426 #endif
427                 setsockopt(CC->client_socket, IPPROTO_TCP, TCP_CORK, &off, 4);
428 #endif
429 }
430
431 void flush_output(void) {
432 #ifdef HAVE_TCP_BUFFERING
433         struct CitContext *CCC = CC;
434         setsockopt(CCC->client_socket, IPPROTO_TCP, TCP_CORK, &off, 4);
435         setsockopt(CCC->client_socket, IPPROTO_TCP, TCP_CORK, &on, 4);
436 #endif
437 }
438
439
440
441 /*
442  * client_write()   ...    Send binary data to the client.
443  */
444 int client_write(const char *buf, int nbytes)
445 {
446         int bytes_written = 0;
447         int retval;
448 #ifndef HAVE_TCP_BUFFERING
449         int old_buffer_len = 0;
450 #endif
451         fd_set wset;
452         CitContext *Ctx;
453         int fdflags;
454
455         Ctx = CC;
456         if (Ctx->redirect_buffer != NULL) {
457                 if ((Ctx->redirect_len + nbytes + 2) >= Ctx->redirect_alloc) {
458                         Ctx->redirect_alloc = (Ctx->redirect_alloc * 2) + nbytes;
459                         Ctx->redirect_buffer = realloc(Ctx->redirect_buffer,
460                                                 Ctx->redirect_alloc);
461                 }
462                 memcpy(&Ctx->redirect_buffer[Ctx->redirect_len], buf, nbytes);
463                 Ctx->redirect_len += nbytes;
464                 Ctx->redirect_buffer[Ctx->redirect_len] = 0;
465                 return 0;
466         }
467
468 #ifdef HAVE_OPENSSL
469         if (Ctx->redirect_ssl) {
470                 client_write_ssl(buf, nbytes);
471                 return 0;
472         }
473 #endif
474
475         fdflags = fcntl(Ctx->client_socket, F_GETFL);
476
477         while (bytes_written < nbytes) {
478                 if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
479                         FD_ZERO(&wset);
480                         FD_SET(Ctx->client_socket, &wset);
481                         if (select(1, NULL, &wset, NULL, NULL) == -1) {
482                                 if (errno == EINTR)
483                                 {
484                                         CtdlLogPrintf(CTDL_DEBUG, "client_write(%d bytes) select() interrupted.\n", nbytes-bytes_written);
485                                         if (CtdlThreadCheckStop()) {
486                                                 CC->kill_me = 1;
487                                                 return (-1);
488                                         } else {
489                                                 /* can't trust fd's and stuff so we need to re-create them */
490                                                 continue;
491                                         }
492                                 } else {
493                                         CtdlLogPrintf(CTDL_ERR,
494                                                 "client_write(%d bytes) select failed: %s (%d)\n",
495                                                 nbytes - bytes_written,
496                                                 strerror(errno), errno);
497                                         cit_backtrace();
498                                         Ctx->kill_me = 1;
499                                         return -1;
500                                 }
501                         }
502                 }
503
504                 retval = write(Ctx->client_socket, &buf[bytes_written],
505                         nbytes - bytes_written);
506                 if (retval < 1) {
507                         CtdlLogPrintf(CTDL_ERR,
508                                 "client_write(%d bytes) failed: %s (%d)\n",
509                                 nbytes - bytes_written,
510                                 strerror(errno), errno);
511                         cit_backtrace();
512                         // CtdlLogPrintf(CTDL_DEBUG, "Tried to send: %s",  &buf[bytes_written]);
513                         Ctx->kill_me = 1;
514                         return -1;
515                 }
516                 bytes_written = bytes_written + retval;
517         }
518         return 0;
519 }
520
521 void cputbuf(const StrBuf *Buf) {   
522         client_write(ChrPtr(Buf), StrLength(Buf)); 
523 }   
524
525
526 /*
527  * cprintf()    Send formatted printable data to the client.
528  *              Implemented in terms of client_write() so it's technically not sysdep...
529  */
530 void cprintf(const char *format, ...) {   
531         va_list arg_ptr;   
532         char buf[1024];
533    
534         va_start(arg_ptr, format);   
535         if (vsnprintf(buf, sizeof buf, format, arg_ptr) == -1)
536                 buf[sizeof buf - 2] = '\n';
537         client_write(buf, strlen(buf)); 
538         va_end(arg_ptr);
539 }   
540
541
542 /*
543  * Read data from the client socket.
544  * Return values are:
545  *      1       Requested number of bytes has been read.
546  *      0       Request timed out.
547  *      -1      The socket is broken.
548  * If the socket breaks, the session will be terminated.
549  */
550 int client_read_to(char *buf, int bytes, int timeout)
551 {
552         int len,rlen;
553         fd_set rfds;
554         int fd;
555         struct timeval tv;
556         int retval;
557
558 #ifdef HAVE_OPENSSL
559         if (CC->redirect_ssl) {
560                 return (client_read_ssl(buf, bytes, timeout));
561         }
562 #endif
563         len = 0;
564         fd = CC->client_socket;
565         while(len<bytes) {
566                 FD_ZERO(&rfds);
567                 FD_SET(fd, &rfds);
568                 tv.tv_sec = timeout;
569                 tv.tv_usec = 0;
570
571                 retval = select( (fd)+1, 
572                                  &rfds, NULL, NULL, &tv);
573                 if (retval < 0)
574                 {
575                         if (errno == EINTR)
576                         {
577                                 CtdlLogPrintf(CTDL_DEBUG, "Interrupted select() in client_read_to().\n");
578                                 if (CtdlThreadCheckStop()) {
579                                         CC->kill_me = 1;
580                                         return (-1);
581                                 } else {
582                                         /* can't trust fd's and stuff so we need to re-create them */
583                                         continue;
584                                 }
585                         }
586                         else {
587                                 CtdlLogPrintf(CTDL_DEBUG, "Failed select() in client_read_to().\n");
588                                 CC->kill_me = 1;
589                                 return (-1);
590                         }
591                 }
592
593                 if (FD_ISSET(fd, &rfds) == 0) {
594                         return(0);
595                 }
596
597                 rlen = read(fd, &buf[len], bytes-len);
598                 if (rlen<1) {
599                         /* The socket has been disconnected! */
600                         CC->kill_me = 1;
601                         return(-1);
602                 }
603                 len = len + rlen;
604         }
605         return(1);
606 }
607
608 /*
609  * Read data from the client socket with default timeout.
610  * (This is implemented in terms of client_read_to() and could be
611  * justifiably moved out of sysdep.c)
612  */
613 INLINE int client_read(char *buf, int bytes)
614 {
615         return(client_read_to(buf, bytes, config.c_sleeping));
616 }
617
618
619 /*
620  * client_getln()   ...   Get a LF-terminated line of text from the client.
621  * (This is implemented in terms of client_read() and could be
622  * justifiably moved out of sysdep.c)
623  */
624 int client_getln(char *buf, int bufsize)
625 {
626         int i, retval;
627
628         /* Read one character at a time.
629          */
630         for (i = 0;;i++) {
631                 retval = client_read(&buf[i], 1);
632                 if (retval != 1 || buf[i] == '\n' || i == (bufsize-1))
633                         break;
634         }
635
636         /* If we got a long line, discard characters until the newline.
637          */
638         if (i == (bufsize-1))
639                 while (buf[i] != '\n' && retval == 1)
640                         retval = client_read(&buf[i], 1);
641
642         /* Strip the trailing LF, and the trailing CR if present.
643          */
644         buf[i] = 0;
645         while ( (i > 0)
646                 && ( (buf[i - 1]==13)
647                      || ( buf[i - 1]==10)) ) {
648                 i--;
649                 buf[i] = 0;
650         }
651         if (retval < 0) safestrncpy(&buf[i], "000", bufsize - i);
652         return(retval);
653 }
654
655
656 /*
657  * Cleanup any contexts that are left lying around
658  */
659
660
661 void close_masters (void)
662 {
663         struct ServiceFunctionHook *serviceptr;
664         
665         /*
666          * close all protocol master sockets
667          */
668         for (serviceptr = ServiceHookTable; serviceptr != NULL;
669             serviceptr = serviceptr->next ) {
670
671                 if (serviceptr->tcp_port > 0)
672                 {
673                         CtdlLogPrintf(CTDL_INFO, "Closing listener on port %d\n",
674                                 serviceptr->tcp_port);
675                         serviceptr->tcp_port = 0;
676                 }
677                 
678                 if (serviceptr->sockpath != NULL)
679                         CtdlLogPrintf(CTDL_INFO, "Closing listener on '%s'\n",
680                                 serviceptr->sockpath);
681
682                 close(serviceptr->msock);
683                 /* If it's a Unix domain socket, remove the file. */
684                 if (serviceptr->sockpath != NULL) {
685                         unlink(serviceptr->sockpath);
686                         serviceptr->sockpath = NULL;
687                 }
688         }
689 }
690
691
692 /*
693  * The system-dependent part of master_cleanup() - close the master socket.
694  */
695 void sysdep_master_cleanup(void) {
696         
697         close_masters();
698         
699         context_cleanup();
700         
701 #ifdef HAVE_OPENSSL
702         destruct_ssl();
703 #endif
704         CtdlDestroyProtoHooks();
705         CtdlDestroyDeleteHooks();
706         CtdlDestroyXmsgHooks();
707         CtdlDestroyNetprocHooks();
708         CtdlDestroyUserHooks();
709         CtdlDestroyMessageHook();
710         CtdlDestroyCleanupHooks();
711         CtdlDestroyFixedOutputHooks();  
712         CtdlDestroySessionHooks();
713         CtdlDestroyServiceHook();
714         CtdlDestroyRoomHooks();
715         #ifdef HAVE_BACKTRACE
716         eCrash_Uninit();
717         #endif
718 }
719
720
721
722 pid_t current_child;
723 void graceful_shutdown(int signum) {
724         kill(current_child, signum);
725         unlink(file_pid_file);
726         exit(0);
727 }
728
729 int nFireUps = 0;
730 int nFireUpsNonRestart = 0;
731 pid_t ForkedPid = 1;
732
733 /*
734  * Start running as a daemon.
735  */
736 void start_daemon(int unused) {
737         int status = 0;
738         pid_t child = 0;
739         FILE *fp;
740         int do_restart = 0;
741
742         current_child = 0;
743
744         /* Close stdin/stdout/stderr and replace them with /dev/null.
745          * We don't just call close() because we don't want these fd's
746          * to be reused for other files.
747          */
748         chdir(ctdl_run_dir);
749
750         child = fork();
751         if (child != 0) {
752                 exit(0);
753         }
754         
755         signal(SIGHUP, SIG_IGN);
756         signal(SIGINT, SIG_IGN);
757         signal(SIGQUIT, SIG_IGN);
758
759         setsid();
760         umask(0);
761         freopen("/dev/null", "r", stdin);
762         freopen("/dev/null", "w", stdout);
763         freopen("/dev/null", "w", stderr);
764
765         do {
766                 current_child = fork();
767
768                 signal(SIGTERM, graceful_shutdown);
769         
770                 if (current_child < 0) {
771                         perror("fork");
772                         exit(errno);
773                 }
774         
775                 else if (current_child == 0) {
776                         return; /* continue starting citadel. */
777                 }
778         
779                 else {
780                         fp = fopen(file_pid_file, "w");
781                         if (fp != NULL) {
782                                 fprintf(fp, ""F_PID_T"\n", getpid());
783                                 fclose(fp);
784                         }
785                         waitpid(current_child, &status, 0);
786                 }
787                 do_restart = 0;
788                 nFireUpsNonRestart = nFireUps;
789                 
790                 /* Exit code 0 means the watcher should exit */
791                 if (WIFEXITED(status) && (WEXITSTATUS(status) == CTDLEXIT_SHUTDOWN)) {
792                         do_restart = 0;
793                 }
794
795                 /* Exit code 101-109 means the watcher should exit */
796                 else if (WIFEXITED(status) && (WEXITSTATUS(status) >= 101) && (WEXITSTATUS(status) <= 109)) {
797                         do_restart = 0;
798                 }
799
800                 /* Any other exit code, or no exit code, means we should restart. */
801                 else {
802                         do_restart = 1;
803                         nFireUps++;
804                         ForkedPid = current_child;
805                 }
806
807         } while (do_restart);
808
809         unlink(file_pid_file);
810         exit(WEXITSTATUS(status));
811 }
812
813
814
815 void checkcrash(void)
816 {
817         if (nFireUpsNonRestart != nFireUps)
818         {
819                 StrBuf *CrashMail;
820
821                 CrashMail = NewStrBuf();
822                 CtdlLogPrintf(CTDL_ALERT, "Posting crash message\n");
823                 StrBufPrintf(CrashMail, 
824                         " \n"
825                         " The Citadel server process (citserver) terminated unexpectedly."
826                         "\n \n"
827                         " This could be the result of a bug in the server program, or some external "
828                         "factor.\n \n"
829                         " You can obtain more information about this by enabling core dumps.\n \n"
830                         " For more information, please see:\n \n"
831                         " http://citadel.org/doku.php/faq:mastering_your_os:gdb#how.do.i.make.my.system.produce.core-files"
832                         "\n \n"
833 "http://www.4players.de/4players.php/walkthrough/Wii/9298/24733/Die_Chroniken_von_Narnia_Prinz_Kaspian_von_Narnia.html"
834
835                         " If you have already done this, the core dump is likely to be found at %score.%d\n"
836                         ,
837                         ctdl_run_dir, ForkedPid);
838                 CtdlAideMessage(ChrPtr(CrashMail), "Citadel server process terminated unexpectedly");
839                 FreeStrBuf(&CrashMail);
840         }
841 }
842
843
844 /*
845  * Generic routine to convert a login name to a full name (gecos)
846  * Returns nonzero if a conversion took place
847  */
848 int convert_login(char NameToConvert[]) {
849         struct passwd *pw;
850         int a;
851
852         pw = getpwnam(NameToConvert);
853         if (pw == NULL) {
854                 return(0);
855         }
856         else {
857                 strcpy(NameToConvert, pw->pw_gecos);
858                 for (a=0; a<strlen(NameToConvert); ++a) {
859                         if (NameToConvert[a] == ',') NameToConvert[a] = 0;
860                 }
861                 return(1);
862         }
863 }
864
865
866
867 /* 
868  * This loop just keeps going and going and going...
869  */
870 /*
871  * FIXME:
872  * This current implimentation of worker_thread creates a bottle neck in several situations
873  * The first thing to remember is that a single thread can handle more than one connection at a time.
874  * More threads mean less memory for the system to run in.
875  * So for efficiency we want every thread to be doing something useful or waiting in the main loop for
876  * something to happen anywhere.
877  * This current implimentation requires worker threads to wait in other locations, after it has
878  * been committed to a single connection which is very wasteful.
879  * As an extreme case consider this:
880  * A slow client connects and this slow client sends only one character each second.
881  * With this current implimentation a single worker thread is dispatched to handle that connection
882  * until such times as the client timeout expires, an error occurs on the socket or the client
883  * completes its transmission.
884  * THIS IS VERY BAD since that thread could have handled a read from many more clients in each one
885  * second interval between chars.
886  *
887  * It is my intention to re-write this code and the associated client_getln, client_read functions
888  * to allow any thread to read data on behalf of any connection (context).
889  * To do this I intend to have this main loop read chars into a buffer stored in the context.
890  * Once the correct criteria for a full buffer is met then we will dispatch a thread to 
891  * process it.
892  * This worker thread loop also needs to be able to handle binary data.
893  */
894  
895 void *worker_thread(void *arg) {
896         int highest;
897         CitContext *ptr;
898         CitContext *bind_me = NULL;
899         fd_set readfds;
900         int retval = 0;
901         struct timeval tv;
902         int force_purge = 0;
903         
904
905         while (!CtdlThreadCheckStop()) {
906
907                 /* make doubly sure we're not holding any stale db handles
908                  * which might cause a deadlock.
909                  */
910                 cdb_check_handles();
911 do_select:      force_purge = 0;
912                 bind_me = NULL;         /* Which session shall we handle? */
913
914                 /* Initialize the fdset. */
915                 FD_ZERO(&readfds);
916                 highest = 0;
917
918                 begin_critical_section(S_SESSION_TABLE);
919                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
920                         /* Dont select on dead sessions only truly idle ones */
921                         if ((ptr->state == CON_IDLE)) {
922                                 FD_SET(ptr->client_socket, &readfds);
923                                 if (ptr->client_socket > highest)
924                                         highest = ptr->client_socket;
925                         }
926                         if ((bind_me == NULL) && (ptr->state == CON_READY)) {
927                                 bind_me = ptr;
928                                 ptr->state = CON_EXECUTING;
929                                 break;
930                         }
931                         if ((bind_me == NULL) && (ptr->state == CON_STARTING)) {
932                                 bind_me = ptr;
933                                 break;
934                         }
935                 }
936                 end_critical_section(S_SESSION_TABLE);
937
938                 if (bind_me) {
939                         goto SKIP_SELECT;
940                 }
941
942                 /* If we got this far, it means that there are no sessions
943                  * which a previous thread marked for attention, so we go
944                  * ahead and get ready to select().
945                  */
946
947                 if (!CtdlThreadCheckStop()) {
948                         tv.tv_sec = 1;          /* wake up every second if no input */
949                         tv.tv_usec = 0;
950                         retval = CtdlThreadSelect(highest + 1, &readfds, NULL, NULL, &tv);
951                 }
952                 else
953                         return NULL;
954
955                 /* Now figure out who made this select() unblock.
956                  * First, check for an error or exit condition.
957                  */
958                 if (retval < 0) {
959                         if (errno == EBADF) {
960                                 CtdlLogPrintf(CTDL_NOTICE, "select() failed: (%s)\n",
961                                         strerror(errno));
962                                 goto do_select;
963                         }
964                         if (errno != EINTR) {
965                                 CtdlLogPrintf(CTDL_EMERG, "Exiting (%s)\n", strerror(errno));
966                                 CtdlThreadStopAll();
967                                 continue;
968                         } else {
969                                 CtdlLogPrintf(CTDL_DEBUG, "Interrupted CtdlThreadSelect.\n");
970                                 if (CtdlThreadCheckStop()) return(NULL);
971                                 goto do_select;
972                         }
973                 }
974                 else if(retval == 0) {
975                         if (CtdlThreadCheckStop()) return(NULL);
976                 }
977
978                 /* It must be a client socket.  Find a context that has data
979                  * waiting on its socket *and* is in the CON_IDLE state.  Any
980                  * active sockets other than our chosen one are marked as
981                  * CON_READY so the next thread that comes around can just bind
982                  * to one without having to select() again.
983                  */
984                 begin_critical_section(S_SESSION_TABLE);
985                 for (ptr = ContextList; ptr != NULL; ptr = ptr->next) {
986                         if ( (FD_ISSET(ptr->client_socket, &readfds))
987                            && (ptr->state != CON_EXECUTING) ) {
988                                 ptr->input_waiting = 1;
989                                 if (!bind_me) {
990                                         bind_me = ptr;  /* I choose you! */
991                                         bind_me->state = CON_EXECUTING;
992                                 }
993                                 else {
994                                         ptr->state = CON_READY;
995                                 }
996                         }
997                 }
998                 end_critical_section(S_SESSION_TABLE);
999
1000 SKIP_SELECT:
1001                 /* We're bound to a session */
1002                 if (bind_me != NULL) {
1003                         become_session(bind_me);
1004
1005                         if (bind_me->state == CON_STARTING) {
1006                                 bind_me->state = CON_EXECUTING;
1007                                 begin_session(bind_me);
1008                                 bind_me->h_greeting_function();
1009                         }
1010                         /* If the client has sent a command, execute it. */
1011                         if (CC->input_waiting) {
1012                                 CC->h_command_function();
1013                                 CC->input_waiting = 0;
1014                         }
1015
1016                         /* If there are asynchronous messages waiting and the
1017                          * client supports it, do those now */
1018                         if ((CC->is_async) && (CC->async_waiting)
1019                            && (CC->h_async_function != NULL)) {
1020                                 CC->h_async_function();
1021                                 CC->async_waiting = 0;
1022                         }
1023                         
1024                         force_purge = CC->kill_me;
1025                         become_session(NULL);
1026                         bind_me->state = CON_IDLE;
1027                 }
1028
1029                 dead_session_purge(force_purge);
1030                 do_housekeeping();
1031         }
1032         /* If control reaches this point, the server is shutting down */        
1033         return(NULL);
1034 }
1035
1036
1037
1038
1039 /*
1040  * A function to handle selecting on master sockets.
1041  * In other words it handles new connections.
1042  * It is a thread.
1043  */
1044 void *select_on_master (void *arg)
1045 {
1046         struct ServiceFunctionHook *serviceptr;
1047         fd_set master_fds;
1048         int highest;
1049         struct timeval tv;
1050         int ssock;                      /* Descriptor for client socket */
1051         CitContext *con= NULL;  /* Temporary context pointer */
1052         int m;
1053         int i;
1054         int retval;
1055
1056         while (!CtdlThreadCheckStop()) {
1057                 /* Initialize the fdset. */
1058                 FD_ZERO(&master_fds);
1059                 highest = 0;
1060
1061                 /* First, add the various master sockets to the fdset. */
1062                 for (serviceptr = ServiceHookTable; serviceptr != NULL;
1063                 serviceptr = serviceptr->next ) {
1064                         m = serviceptr->msock;
1065                         FD_SET(m, &master_fds);
1066                         if (m > highest) {
1067                                 highest = m;
1068                         }
1069                 }
1070
1071                 if (!CtdlThreadCheckStop()) {
1072                         tv.tv_sec = 60;         /* wake up every second if no input */
1073                         tv.tv_usec = 0;
1074                         retval = CtdlThreadSelect(highest + 1, &master_fds, NULL, NULL, &tv);
1075                 }
1076                 else
1077                         return NULL;
1078
1079                 /* Now figure out who made this select() unblock.
1080                  * First, check for an error or exit condition.
1081                  */
1082                 if (retval < 0) {
1083                         if (errno == EBADF) {
1084                                 CtdlLogPrintf(CTDL_NOTICE, "select() failed: (%s)\n",
1085                                         strerror(errno));
1086                                 continue;
1087                         }
1088                         if (errno != EINTR) {
1089                                 CtdlLogPrintf(CTDL_EMERG, "Exiting (%s)\n", strerror(errno));
1090                                 CtdlThreadStopAll();
1091                         } else {
1092                                 CtdlLogPrintf(CTDL_DEBUG, "Interrupted CtdlThreadSelect.\n");
1093                                 if (CtdlThreadCheckStop()) return(NULL);
1094                                 continue;
1095                         }
1096                 }
1097                 else if(retval == 0) {
1098                         if (CtdlThreadCheckStop()) return(NULL);
1099                         continue;
1100                 }
1101                 /* Next, check to see if it's a new client connecting
1102                  * on a master socket.
1103                  */
1104                 else for (serviceptr = ServiceHookTable; serviceptr != NULL;
1105                      serviceptr = serviceptr->next ) {
1106
1107                         if (FD_ISSET(serviceptr->msock, &master_fds)) {
1108                                 ssock = accept(serviceptr->msock, NULL, 0);
1109                                 if (ssock >= 0) {
1110                                         CtdlLogPrintf(CTDL_DEBUG,
1111                                                 "New client socket %d\n",
1112                                                 ssock);
1113
1114                                         /* The master socket is non-blocking but the client
1115                                          * sockets need to be blocking, otherwise certain
1116                                          * operations barf on FreeBSD.  Not a fatal error.
1117                                          */
1118                                         if (fcntl(ssock, F_SETFL, 0) < 0) {
1119                                                 CtdlLogPrintf(CTDL_EMERG,
1120                                                         "citserver: Can't set socket to blocking: %s\n",
1121                                                         strerror(errno));
1122                                         }
1123
1124                                         /* New context will be created already
1125                                          * set up in the CON_EXECUTING state.
1126                                          */
1127                                         con = CreateNewContext();
1128
1129                                         /* Assign our new socket number to it. */
1130                                         con->client_socket = ssock;
1131                                         con->h_command_function =
1132                                                 serviceptr->h_command_function;
1133                                         con->h_async_function =
1134                                                 serviceptr->h_async_function;
1135                                         con->h_greeting_function = serviceptr->h_greeting_function;
1136                                         con->ServiceName =
1137                                                 serviceptr->ServiceName;
1138                                         
1139                                         /* Determine whether it's a local socket */
1140                                         if (serviceptr->sockpath != NULL)
1141                                                 con->is_local_socket = 1;
1142         
1143                                         /* Set the SO_REUSEADDR socket option */
1144                                         i = 1;
1145                                         setsockopt(ssock, SOL_SOCKET,
1146                                                 SO_REUSEADDR,
1147                                                 &i, sizeof(i));
1148
1149                                         con->state = CON_STARTING;
1150
1151                                         retval--;
1152                                         if (retval == 0)
1153                                                 break;
1154                                 }
1155                         }
1156                 }
1157         }
1158         return NULL;
1159 }
1160
1161
1162
1163 /*
1164  * SyslogFacility()
1165  * Translate text facility name to syslog.h defined value.
1166  */
1167 int SyslogFacility(char *name)
1168 {
1169         int i;
1170         struct
1171         {
1172                 int facility;
1173                 char *name;
1174         }   facTbl[] =
1175         {
1176                 {   LOG_KERN,   "kern"          },
1177                 {   LOG_USER,   "user"          },
1178                 {   LOG_MAIL,   "mail"          },
1179                 {   LOG_DAEMON, "daemon"        },
1180                 {   LOG_AUTH,   "auth"          },
1181                 {   LOG_SYSLOG, "syslog"        },
1182                 {   LOG_LPR,    "lpr"           },
1183                 {   LOG_NEWS,   "news"          },
1184                 {   LOG_UUCP,   "uucp"          },
1185                 {   LOG_LOCAL0, "local0"        },
1186                 {   LOG_LOCAL1, "local1"        },
1187                 {   LOG_LOCAL2, "local2"        },
1188                 {   LOG_LOCAL3, "local3"        },
1189                 {   LOG_LOCAL4, "local4"        },
1190                 {   LOG_LOCAL5, "local5"        },
1191                 {   LOG_LOCAL6, "local6"        },
1192                 {   LOG_LOCAL7, "local7"        },
1193                 {   0,            NULL          }
1194         };
1195         for(i = 0; facTbl[i].name != NULL; i++) {
1196                 if(!strcasecmp(name, facTbl[i].name))
1197                         return facTbl[i].facility;
1198         }
1199         enable_syslog = 0;
1200         return LOG_DAEMON;
1201 }
1202
1203
1204 /********** MEM CHEQQER ***********/
1205
1206 #ifdef DEBUG_MEMORY_LEAKS
1207
1208 #undef malloc
1209 #undef realloc
1210 #undef strdup
1211 #undef free
1212
1213 void *tracked_malloc(size_t size, char *file, int line) {
1214         struct igheap *thisheap;
1215         void *block;
1216
1217         block = malloc(size);
1218         if (block == NULL) return(block);
1219
1220         thisheap = malloc(sizeof(struct igheap));
1221         if (thisheap == NULL) {
1222                 free(block);
1223                 return(NULL);
1224         }
1225
1226         thisheap->block = block;
1227         strcpy(thisheap->file, file);
1228         thisheap->line = line;
1229         
1230         begin_critical_section(S_DEBUGMEMLEAKS);
1231         thisheap->next = igheap;
1232         igheap = thisheap;
1233         end_critical_section(S_DEBUGMEMLEAKS);
1234
1235         return(block);
1236 }
1237
1238
1239 void *tracked_realloc(void *ptr, size_t size, char *file, int line) {
1240         struct igheap *thisheap;
1241         void *block;
1242
1243         block = realloc(ptr, size);
1244         if (block == NULL) return(block);
1245
1246         thisheap = malloc(sizeof(struct igheap));
1247         if (thisheap == NULL) {
1248                 free(block);
1249                 return(NULL);
1250         }
1251
1252         thisheap->block = block;
1253         strcpy(thisheap->file, file);
1254         thisheap->line = line;
1255         
1256         begin_critical_section(S_DEBUGMEMLEAKS);
1257         thisheap->next = igheap;
1258         igheap = thisheap;
1259         end_critical_section(S_DEBUGMEMLEAKS);
1260
1261         return(block);
1262 }
1263
1264
1265
1266 void tracked_free(void *ptr) {
1267         struct igheap *thisheap;
1268         struct igheap *trash;
1269
1270         free(ptr);
1271
1272         if (igheap == NULL) return;
1273         begin_critical_section(S_DEBUGMEMLEAKS);
1274         for (thisheap = igheap; thisheap != NULL; thisheap = thisheap->next) {
1275                 if (thisheap->next != NULL) {
1276                         if (thisheap->next->block == ptr) {
1277                                 trash = thisheap->next;
1278                                 thisheap->next = thisheap->next->next;
1279                                 free(trash);
1280                         }
1281                 }
1282         }
1283         if (igheap->block == ptr) {
1284                 trash = igheap;
1285                 igheap = igheap->next;
1286                 free(trash);
1287         }
1288         end_critical_section(S_DEBUGMEMLEAKS);
1289 }
1290
1291 char *tracked_strdup(const char *s, char *file, int line) {
1292         char *ptr;
1293
1294         if (s == NULL) return(NULL);
1295         ptr = tracked_malloc(strlen(s) + 1, file, line);
1296         if (ptr == NULL) return(NULL);
1297         strncpy(ptr, s, strlen(s));
1298         return(ptr);
1299 }
1300
1301 void dump_heap(void) {
1302         struct igheap *thisheap;
1303
1304         for (thisheap = igheap; thisheap != NULL; thisheap = thisheap->next) {
1305                 CtdlLogPrintf(CTDL_CRIT, "UNFREED: %30s : %d\n",
1306                         thisheap->file, thisheap->line);
1307         }
1308 }
1309
1310 #endif /*  DEBUG_MEMORY_LEAKS */