src/misc-progs/syslogdctrl.c

   1 /* This file is part of the IPCop Firewall.
   2  *
   3  * This program is distributed under the terms of the GNU General Public
   4  * Licence.  See the file COPYING for details.
   5  *
   6  * Copyright (C) 2003-07-12 Robert Kerr <rkerr@go.to>
   7  *
   8  * $Id$
   9  *
  10  * Edited by the IPFire Team to change var log messages
  11  */
  12
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <unistd.h>
  16 #include <string.h>
  17 #include <sys/stat.h>
  18 #include <sys/types.h>
  19 #include <fcntl.h>
  20 #include <signal.h>
  21 #include <errno.h>
  22 #include "libsmooth.h"
  23 #include "setuid.h"
  24
  25 #define ERR_ANY 1
  26 #define ERR_SETTINGS 2    /* error in settings file */
  27 #define ERR_ETC 3         /* error with /etc permissions */
  28 #define ERR_CONFIG 4      /* error updated sshd_config */
  29 #define ERR_SYSLOG 5      /* error restarting syslogd */
  30
  31 int main(void)
  32 {
  33    char buffer[STRING_SIZE], command[STRING_SIZE], hostname[STRING_SIZE], varmessages[STRING_SIZE];
  34    int config_fd,rc,fd,pid;
  35    struct stat st;
  36    struct keyvalue *kv = NULL;
  37    memset(buffer, 0, STRING_SIZE);
  38    memset(hostname, 0, STRING_SIZE);
  39    memset(varmessages, 0, STRING_SIZE);
  40
  41    if (!(initsetuid()))
  42       exit(1);
  43
  44
  45    /* Read in and verify config */
  46    kv=initkeyvalues();
  47
  48    if (!readkeyvalues(kv, "/var/ipfire/logging/settings"))
  49    {
  50       fprintf(stderr, "Cannot read syslog settings\n");
  51       exit(ERR_SETTINGS);
  52    }
  53
  54    if (!findkey(kv, "ENABLE_REMOTELOG", buffer))
  55    {
  56       fprintf(stderr, "Cannot read ENABLE_REMOTELOG\n");
  57       exit(ERR_SETTINGS);
  58    }
  59
  60    if (!findkey(kv, "REMOTELOG_ADDR", hostname))
  61    {
  62       fprintf(stderr, "Cannot read REMOTELOG_ADDR\n");
  63       exit(ERR_SETTINGS);
  64    }
  65
  66    if (!findkey(kv, "VARMESSAGES", varmessages))
  67    {
  68       fprintf(stderr, "Cannot read VARMESSAGES\n");
  69       exit(ERR_SETTINGS);
  70    }
  71
  72    if (strspn(hostname, VALID_FQDN) != strlen(hostname))
  73    {
  74       fprintf(stderr, "Bad REMOTELOG_ADDR: %s\n", hostname);
  75       exit(ERR_SETTINGS);
  76    }
  77
  78    freekeyvalues(kv);
  79
  80
  81    /* If anyone other than root can write to /etc this would be totally
  82     * insecure - same if anyone other than root owns /etc, as they could
  83     * change the file mode to give themselves or anyone else write access. */
  84
  85    if(lstat("/etc",&st))
  86    {
  87       perror("Unable to stat /etc");
  88       exit(ERR_ETC);
  89    }
  90    if(!S_ISDIR(st.st_mode))
  91    {
  92       fprintf(stderr, "/etc is not a directory?!\n");
  93       exit(ERR_ETC);
  94    }
  95    if ( st.st_uid != 0  ||  st.st_mode & S_IWOTH ||
  96       ((st.st_gid != 0) && (st.st_mode & S_IWGRP)) )
  97    {
  98       fprintf(stderr, "/etc is owned/writable by non-root users\n");
  99       exit(ERR_ETC);
 100    }
 101
 102    /* O_CREAT with O_EXCL will make open() fail if the file already exists -
 103     * mostly to prevent 2 copies running at once */
 104    if ((config_fd = open( "/etc/syslog.conf.new", O_WRONLY|O_CREAT|O_EXCL, 0644 )) == -1 )
 105    {
 106       perror("Unable to open new config file");
 107       exit(ERR_CONFIG);
 108    }
 109
 110    if (!strcmp(buffer,"on"))
 111       snprintf(buffer, STRING_SIZE - 1, "/bin/sed -e 's/^#\\?\\(\\*\\.\\*[[:blank:]]\\+@\\).\\+$/\\1%s/' /etc/syslog.conf >&%d", hostname, config_fd );
 112    else
 113       snprintf(buffer, STRING_SIZE - 1, "/bin/sed -e 's/^#\\?\\(\\*\\.\\*[[:blank:]]\\+@.\\+\\)$/#\\1/' /etc/syslog.conf >&%d", config_fd );
 114
 115      /* if the return code isn't 0 failsafe */
 116    if ((rc = unpriv_system(buffer,99,99)) != 0)
 117    {
 118       fprintf(stderr, "sed returned bad exit code: %d\n", rc);
 119       close(config_fd);
 120       unlink("/etc/syslog.conf.new");
 121       exit(ERR_CONFIG);
 122    }
 123    close(config_fd);
 124
 125    /* Replace the logging option*/
 126      safe_system("grep -v '/var/log/messages' < /etc/syslog.conf.new > /etc/syslog.conf.tmp && mv /etc/syslog.conf.tmp /etc/syslog.conf.new");
 127
 128    if (strcmp(ENABLE_ASYNCLOG,"on"))
 129      snprintf(command, STRING_SIZE-1, "printf '%s     -/var/log/messages' >> /etc/syslog.conf.new", varmessages );
 130    else
 131      snprintf(command, STRING_SIZE-1, "printf '%s     /var/log/messages' >> /etc/syslog.conf.new", varmessages );
 132
 133      safe_system(command);
 134
 135    if (rename("/etc/syslog.conf.new", "/etc/syslog.conf") == -1)
 136    {
 137       perror("Unable to replace old config file");
 138       unlink("/etc/syslog.conf.new");
 139       exit(ERR_CONFIG);
 140    }
 141
 142
 143    /* Get syslogd to read the new config file */
 144    if ((fd = open("/var/run/syslogd.pid", O_RDONLY)) == -1)
 145    {
 146       if(errno == ENOENT)
 147       {
 148          /* pid file doesn't exists.. restart syslog */
 149          if((rc = safe_system("/usr/sbin/syslogd u syslogd -m 0")) == 0 )
 150             return 0;
 151          else
 152          {
 153             fprintf(stderr,
 154                "Unable to restart syslogd - returned exit code %d\n", rc);
 155             exit(ERR_SYSLOG);
 156          }
 157       } else {
 158          /* Something odd is going on, failsafe */
 159          perror("Unable to open pid file");
 160          exit(ERR_SYSLOG);
 161       }
 162    }
 163
 164    memset(buffer, 0, STRING_SIZE);
 165    if (read(fd, buffer, STRING_SIZE - 1) == -1)
 166    {
 167       close(fd);
 168       perror("Couldn't read from pid file");
 169       exit(ERR_SYSLOG);
 170    }
 171    close(fd);
 172    /* strtol does sanity checks that atoi doesn't do */
 173    errno = 0;
 174    pid = (int)strtol(buffer, (char **)NULL, 10);
 175    if (errno || pid <= 1)
 176    {
 177       fprintf(stderr, "Bad pid value\n");
 178       exit(ERR_SYSLOG);
 179    }
 180    if (kill(pid, SIGHUP) == -1)
 181    {
 182       fprintf(stderr, "Unable to send SIGHUP\n");
 183       exit(ERR_SYSLOG);
 184    }
 185
 186    return 0;
 187 }