citadel/serv_spam.c

   1 /*
   2  * $Id$
   3  *
   4  * Reject incoming SMTP messages containing strings that tell us that the
   5  * message is probably spam.
   6  *
   7  */
   8
   9
  10 #include "sysdep.h"
  11 #include <stdlib.h>
  12 #include <unistd.h>
  13 #include <stdio.h>
  14 #include <fcntl.h>
  15 #include <signal.h>
  16 #include <pwd.h>
  17 #include <errno.h>
  18 #include <sys/types.h>
  19
  20 #if TIME_WITH_SYS_TIME
  21 # include <sys/time.h>
  22 # include <time.h>
  23 #else
  24 # if HAVE_SYS_TIME_H
  25 #  include <sys/time.h>
  26 # else
  27 #  include <time.h>
  28 # endif
  29 #endif
  30
  31 #include <sys/wait.h>
  32 #include <string.h>
  33 #include <limits.h>
  34 #include "citadel.h"
  35 #include "server.h"
  36 #include "sysdep_decls.h"
  37 #include "citserver.h"
  38 #include "support.h"
  39 #include "config.h"
  40 #include "control.h"
  41 #include "dynloader.h"
  42 #include "room_ops.h"
  43 #include "user_ops.h"
  44 #include "policy.h"
  45 #include "database.h"
  46 #include "msgbase.h"
  47 #include "tools.h"
  48 #include "internet_addressing.h"
  49
  50
  51 /* Scan a message for spam */
  52 int spam_filter(struct CtdlMessage *msg) {
  53         int spam_strings_found = 0;
  54         struct spamstrings_t *sptr;
  55         char *ptr;
  56
  57         /* Bail out if there's no message text */
  58         if (msg->cm_fields['M'] == NULL) return(0);
  59
  60
  61         /* Scan! */
  62         ptr = msg->cm_fields['M'];
  63         while (ptr++[0] != 0) {
  64                 for (sptr = spamstrings; sptr != NULL; sptr = sptr->next) {
  65                         if (!strncasecmp(ptr, sptr->string,
  66                            strlen(sptr->string))) {
  67                                 ++spam_strings_found;
  68                         }
  69                 }
  70         }
  71
  72         if (spam_strings_found) {
  73                 if (msg->cm_fields['0'] != NULL) {
  74                         phree(msg->cm_fields['0']);
  75                 }
  76                 msg->cm_fields['0'] = strdoop("Unsolicited spam rejected");
  77                 return(spam_strings_found);
  78         }
  79
  80         return(0);
  81 }
  82
  83
  84
  85 char *Dynamic_Module_Init(void)
  86 {
  87         CtdlRegisterMessageHook(spam_filter, EVT_SMTPSCAN);
  88         return "$Id$";
  89 }