webcit/sysdep.c

   1 /*
   2  * $Id: sysdep.c 5691 2007-11-04 23:19:17Z dothebart $
   3  *
   4  * Citadel "system dependent" stuff.
   5  * See copyright.txt 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 #ifdef HAVE_PTHREAD_H
  53 #include <pthread.h>
  54 #endif
  55 #include "webcit.h"
  56 #include "sysdep.h"
  57
  58 #ifdef HAVE_SYS_SELECT_H
  59 #include <sys/select.h>
  60 #endif
  61
  62 #ifndef HAVE_SNPRINTF
  63 #include "snprintf.h"
  64 #endif
  65
  66 #include "webserver.h"
  67
  68 pthread_mutex_t Critters[MAX_SEMAPHORES];       /* Things needing locking */
  69 pthread_key_t MyConKey;                         /* TSD key for MyContext() */
  70 pthread_key_t MyReq;                            /* TSD key for MyReq() */
  71
  72 void InitialiseSemaphores(void)
  73 {
  74         int i;
  75
  76         /* Set up a bunch of semaphores to be used for critical sections */
  77         for (i=0; i<MAX_SEMAPHORES; ++i) {
  78                 pthread_mutex_init(&Critters[i], NULL);
  79         }
  80 }
  81
  82 /*
  83  * Obtain a semaphore lock to begin a critical section.
  84  */
  85 void begin_critical_section(int which_one)
  86 {
  87         /* lprintf(CTDL_DEBUG, "begin_critical_section(%d)\n", which_one); */
  88         pthread_mutex_lock(&Critters[which_one]);
  89 }
  90
  91 /*
  92  * Release a semaphore lock to end a critical section.
  93  */
  94 void end_critical_section(int which_one)
  95 {
  96         pthread_mutex_unlock(&Critters[which_one]);
  97 }
  98
  99 void drop_root(uid_t UID)
 100 {
 101         struct passwd pw, *pwp = NULL;
 102
 103         /*
 104          * Now that we've bound the sockets, change to the Citadel user id and its
 105          * corresponding group ids
 106          */
 107         if (UID != -1) {
 108
 109 #ifdef HAVE_GETPWUID_R
 110 #ifdef SOLARIS_GETPWUID
 111                 pwp = getpwuid_r(UID, &pw, pwbuf, sizeof(pwbuf));
 112 #else // SOLARIS_GETPWUID
 113                 getpwuid_r(UID, &pw, pwbuf, sizeof(pwbuf), &pwp);
 114 #endif // SOLARIS_GETPWUID
 115 #else // HAVE_GETPWUID_R
 116                 pwp = NULL;
 117 #endif // HAVE_GETPWUID_R
 118
 119                 if (pwp == NULL)
 120                         lprintf(CTDL_CRIT, "WARNING: getpwuid(%ld): %s\n"
 121                                 "Group IDs will be incorrect.\n", UID,
 122                                 strerror(errno));
 123                 else {
 124                         initgroups(pw.pw_name, pw.pw_gid);
 125                         if (setgid(pw.pw_gid))
 126                                 lprintf(CTDL_CRIT, "setgid(%ld): %s\n", (long)pw.pw_gid,
 127                                         strerror(errno));
 128                 }
 129                 lprintf(CTDL_INFO, "Changing uid to %ld\n", (long)UID);
 130                 if (setuid(UID) != 0) {
 131                         lprintf(CTDL_CRIT, "setuid() failed: %s\n", strerror(errno));
 132                 }
 133 #if defined (HAVE_SYS_PRCTL_H) && defined (PR_SET_DUMPABLE)
 134                 prctl(PR_SET_DUMPABLE, 1);
 135 #endif
 136         }
 137 }