Support Rspamd. Patch from Andrew Lewis, lightly editorialised
[exim.git] / src / src / spam.c
index 3d38d99dd6a7747f1d527a70eafc7ef9cf7fd471..71993fb7fd61c110bfd4a32ee18e1c13f292aa65 100644 (file)
@@ -1,5 +1,3 @@
-/* $Cambridge: exim/src/src/spam.c,v 1.18 2010/06/05 11:13:30 pdp Exp $ */
-
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 uschar spam_score_buffer[16];
 uschar spam_score_int_buffer[16];
 uschar spam_bar_buffer[128];
+uschar spam_action_buffer[32];
 uschar spam_report_buffer[32600];
 uschar prev_user_name[128] = "";
 int spam_ok = 0;
 int spam_rc = 0;
 uschar *prev_spamd_address_work = NULL;
 
-int spam(uschar **listptr) {
+int
+spam(uschar **listptr)
+{
   int sep = 0;
   uschar *list = *listptr;
   uschar *user_name;
   uschar user_name_buffer[128];
   unsigned long mbox_size;
   FILE *mbox_file;
-  int spamd_sock;
+  int spamd_sock = -1;
   uschar spamd_buffer[32600];
   int i, j, offset, result;
+  BOOL is_rspamd;
   uschar spamd_version[8];
+  uschar spamd_short_result[8];
   uschar spamd_score_char;
-  double spamd_threshold, spamd_score;
+  double spamd_threshold, spamd_score, spamd_reject_score;
   int spamd_report_offset;
   uschar *p,*q;
   int override = 0;
@@ -48,6 +51,7 @@ int spam(uschar **listptr) {
   fd_set select_fd;
 #endif
   uschar *spamd_address_work;
+  static const uschar * loglabel = US"spam acl condition:";
 
   /* stop compiler warning */
   result = 0;
@@ -55,62 +59,64 @@ int spam(uschar **listptr) {
   /* find the username from the option list */
   if ((user_name = string_nextinlist(&list, &sep,
                                      user_name_buffer,
-                                     sizeof(user_name_buffer))) == NULL) {
+                                     sizeof(user_name_buffer))) == NULL)
+    {
     /* no username given, this means no scanning should be done */
     return FAIL;
-  };
+    }
 
   /* if username is "0" or "false", do not scan */
   if ( (Ustrcmp(user_name,"0") == 0) ||
-       (strcmpic(user_name,US"false") == 0) ) {
+       (strcmpic(user_name,US"false") == 0) )
     return FAIL;
-  };
 
   /* if there is an additional option, check if it is "true" */
-  if (strcmpic(list,US"true") == 0) {
+  if (strcmpic(list,US"true") == 0)
     /* in that case, always return true later */
     override = 1;
-  };
 
   /* expand spamd_address if needed */
-  if (*spamd_address == '$') {
+  if (*spamd_address == '$')
+    {
     spamd_address_work = expand_string(spamd_address);
-    if (spamd_address_work == NULL) {
+    if (spamd_address_work == NULL)
+      {
       log_write(0, LOG_MAIN|LOG_PANIC,
-        "spamassassin acl condition: spamd_address starts with $, but expansion failed: %s", expand_string_message);
+        "%s spamd_address starts with $, but expansion failed: %s",
+       loglabel, expand_string_message);
       return DEFER;
+      }
     }
-  }
   else
     spamd_address_work = spamd_address;
 
   /* check if previous spamd_address was expanded and has changed. dump cached results if so */
-  if ( spam_ok && ( prev_spamd_address_work != NULL) && (Ustrcmp(prev_spamd_address_work, spamd_address_work) != 0)) {
+  if (  spam_ok
+     && prev_spamd_address_work != NULL
+     && Ustrcmp(prev_spamd_address_work, spamd_address_work) != 0
+     )
     spam_ok = 0;
-  }
 
   /* if we scanned for this username last time, just return */
-  if ( spam_ok && ( Ustrcmp(prev_user_name, user_name) == 0 ) ) {
-    if (override)
-      return OK;
-    else
-      return spam_rc;
-  };
+  if (spam_ok && Ustrcmp(prev_user_name, user_name) == 0)
+    return override ? OK : spam_rc;
 
   /* make sure the eml mbox file is spooled up */
   mbox_file = spool_mbox(&mbox_size, NULL);
 
-  if (mbox_file == NULL) {
+  if (mbox_file == NULL)
+    {
     /* error while spooling */
     log_write(0, LOG_MAIN|LOG_PANIC,
-           "spam acl condition: error while creating mbox spool file");
+           "%s error while creating mbox spool file", loglabel);
     return DEFER;
-  };
+    }
 
   start = time(NULL);
 
   /* socket does not start with '/' -> network socket */
-  if (*spamd_address_work != '/') {
+  if (*spamd_address_work != '/')
+    {
     int num_servers = 0;
     int current_server;
     uschar *address = NULL;
@@ -122,62 +128,74 @@ int spam(uschar **listptr) {
        and register their addresses */
     while ((address = string_nextinlist(&spamd_address_list_ptr, &sep,
                                         address_buffer,
-                                        sizeof(address_buffer))) != NULL) {
+                                        sizeof(address_buffer))) != NULL)
+      {
 
       /* Potential memory leak as we never free the store. */
       spamd_address_container *this_spamd =
         (spamd_address_container *)store_get(sizeof(spamd_address_container));
 
+      /* Check for spamd variant */
+      this_spamd->is_rspamd = Ustrstr(address, "variant=rspamd") != NULL;
+
       /* grok spamd address and port */
-      if( sscanf(CS address, "%s %u", this_spamd->tcp_addr, &(this_spamd->tcp_port)) != 2 ) {
+      if (sscanf(CS address, "%23s %hu", this_spamd->tcp_addr, &this_spamd->tcp_port) != 2)
+        {
         log_write(0, LOG_MAIN,
-          "spam acl condition: warning - invalid spamd address: '%s'", address);
+          "%s warning - invalid spamd address: '%s'", loglabel, address);
         continue;
-      };
+       }
 
       spamd_address_vector[num_servers] = this_spamd;
-      num_servers++;
-      if (num_servers > 31)
+      if (  ++num_servers
+        >= sizeof(spamd_address_vector)/sizeof(spamd_address_vector[0]))
         break;
-    };
+      }
 
     /* check if we have at least one server */
-    if (!num_servers) {
+    if (!num_servers)
+      {
       log_write(0, LOG_MAIN|LOG_PANIC,
-         "spam acl condition: no useable spamd server addresses in spamd_address configuration option.");
+         "%s no useable spamd server addresses in spamd_address configuration option.",
+        loglabel);
       (void)fclose(mbox_file);
       return DEFER;
-    };
+      }
 
-    while ( num_servers > 0 ) {
+    while (num_servers > 0)
+      {
       int i;
 
       /* Randomly pick a server to try */
-      current_server = random_number( num_servers );
+      current_server = random_number(num_servers);
 
       debug_printf("trying server %s, port %u\n",
                    spamd_address_vector[current_server]->tcp_addr,
                    spamd_address_vector[current_server]->tcp_port);
 
       /* contact a spamd */
-      if ( (spamd_sock = ip_socket(SOCK_STREAM, AF_INET)) < 0) {
+      if ((spamd_sock = ip_socket(SOCK_STREAM, AF_INET)) < 0)
+       {
         log_write(0, LOG_MAIN|LOG_PANIC,
-           "spam acl condition: error creating IP socket for spamd");
+           "%s error creating IP socket for spamd", loglabel);
         (void)fclose(mbox_file);
         return DEFER;
-      };
-
-      if (ip_connect( spamd_sock,
-                      AF_INET,
-                      spamd_address_vector[current_server]->tcp_addr,
-                      spamd_address_vector[current_server]->tcp_port,
-                      5 ) > -1) {
+       }
+
+      if (ip_connect(spamd_sock,
+                     AF_INET,
+                     spamd_address_vector[current_server]->tcp_addr,
+                     spamd_address_vector[current_server]->tcp_port,
+                     5 ) > -1)
+       {
         /* connection OK */
+        is_rspamd = spamd_address_vector[current_server]->is_rspamd;
         break;
-      };
+       }
 
       log_write(0, LOG_MAIN|LOG_PANIC,
-         "spam acl condition: warning - spamd connection to %s, port %u failed: %s",
+         "%s warning - spamd connection to %s, port %u failed: %s",
+        loglabel,
          spamd_address_vector[current_server]->tcp_addr,
          spamd_address_vector[current_server]->tcp_port,
          strerror(errno));
@@ -186,58 +204,109 @@ int spam(uschar **listptr) {
 
       /* Remove the server from the list. XXX We should free the memory */
       num_servers--;
-      for( i = current_server; i < num_servers; i++ )
+      for (i = current_server; i < num_servers; i++)
         spamd_address_vector[i] = spamd_address_vector[i+1];
-    }
+      }
 
-    if ( num_servers == 0 ) {
-      log_write(0, LOG_MAIN|LOG_PANIC, "spam acl condition: all spamd servers failed");
+    if (num_servers == 0)
+      {
+      log_write(0, LOG_MAIN|LOG_PANIC, "%s all spamd servers failed", loglabel);
       (void)fclose(mbox_file);
       return DEFER;
+      }
     }
-
-  }
-  else {
+  else
+    {
     /* open the local socket */
 
-    if ((spamd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
+    if ((spamd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+      {
       log_write(0, LOG_MAIN|LOG_PANIC,
-                "malware acl condition: spamd: unable to acquire socket (%s)",
+                "%s spamd: unable to acquire socket (%s)",
+               loglabel,
                 strerror(errno));
       (void)fclose(mbox_file);
       return DEFER;
-    }
+      }
 
     server.sun_family = AF_UNIX;
-    Ustrcpy(server.sun_path, spamd_address_work);
 
-    if (connect(spamd_sock, (struct sockaddr *) &server, sizeof(struct sockaddr_un)) < 0) {
+    is_rspamd = (p = Ustrstr(spamd_address_work, "variant=rspamd")) != NULL;
+    if (is_rspamd)
+      {
+      /* strip spaces */
+      p--;
+      while (p > spamd_address_work && isspace (*p))
+        p--;
+      Ustrncpy(server.sun_path, spamd_address_work, p - spamd_address_work + 1);
+      /* zero terminate */
+      server.sun_path[p - spamd_address_work + 1] = 0;
+      }
+    else
+      Ustrcpy(server.sun_path, spamd_address_work);
+
+    if (connect(spamd_sock, (struct sockaddr *) &server, sizeof(struct sockaddr_un)) < 0)
+      {
       log_write(0, LOG_MAIN|LOG_PANIC,
-                "malware acl condition: spamd: unable to connect to UNIX socket %s (%s)",
-                spamd_address_work, strerror(errno) );
+                "%s spamd: unable to connect to UNIX socket %s (%s)",
+               loglabel,
+                server.sun_path, strerror(errno) );
       (void)fclose(mbox_file);
       (void)close(spamd_sock);
       return DEFER;
+      }
     }
 
-  }
+  if (spamd_sock == -1)
+    {
+    log_write(0, LOG_MAIN|LOG_PANIC,
+        "programming fault, spamd_sock unexpectedly unset");
+    (void)fclose(mbox_file);
+    (void)close(spamd_sock);
+    return DEFER;
+    }
 
+  (void)fcntl(spamd_sock, F_SETFL, O_NONBLOCK);
   /* now we are connected to spamd on spamd_sock */
-  (void)string_format(spamd_buffer,
-           sizeof(spamd_buffer),
-           "REPORT SPAMC/1.2\r\nUser: %s\r\nContent-length: %ld\r\n\r\n",
-           user_name,
-           mbox_size);
-
-  /* send our request */
-  if (send(spamd_sock, spamd_buffer, Ustrlen(spamd_buffer), 0) < 0) {
+  if (is_rspamd)
+    {                          /* rspamd variant */
+    uschar *req_str;
+    const char *helo;
+    const char *fcrdns;
+    req_str = string_sprintf("CHECK RSPAMC/1.3\r\nContent-length: %lu\r\n"
+      "Queue-Id: %s\r\nFrom: <%s>\r\nRecipient-Number: %d\r\n", mbox_size,
+      message_id, sender_address, recipients_count);
+    for (i = 0; i < recipients_count; i ++)
+      req_str = string_sprintf("%sRcpt: <%s>\r\n", req_str, recipients_list[i].address);
+    if ((helo = expand_string(US"$sender_helo_name")) != NULL && *helo != '\0')
+      req_str = string_sprintf("%sHelo: %s\r\n", req_str, helo);
+    if ((fcrdns = expand_string(US"$sender_host_name")) != NULL && *fcrdns != '\0')
+      req_str = string_sprintf("%sHostname: %s\r\n", req_str, fcrdns);
+    if (sender_host_address != NULL)
+      req_str = string_sprintf("%sIP: %s\r\n", req_str, sender_host_address);
+    req_str = string_sprintf("%s\r\n", req_str);
+    wrote = send(spamd_sock, req_str, Ustrlen(req_str), 0); 
+    }
+    else
+    {                          /* spamassassin variant */
+    (void)string_format(spamd_buffer,
+            sizeof(spamd_buffer),
+            "REPORT SPAMC/1.2\r\nUser: %s\r\nContent-length: %ld\r\n\r\n",
+            user_name,
+            mbox_size);
+    /* send our request */
+    wrote = send(spamd_sock, spamd_buffer, Ustrlen(spamd_buffer), 0);
+    }
+  if (wrote == -1)
+    {
     (void)close(spamd_sock);
     log_write(0, LOG_MAIN|LOG_PANIC,
-         "spam acl condition: spamd send failed: %s", strerror(errno));
+         "%s spamd send failed: %s", loglabel, strerror(errno));
     (void)fclose(mbox_file);
     (void)close(spamd_sock);
     return DEFER;
-  };
+    }
 
   /* now send the file */
   /* spamd sometimes accepts conections but doesn't read data off
@@ -254,9 +323,11 @@ int spam(uschar **listptr) {
   pollfd.events = POLLOUT;
 #endif
   (void)fcntl(spamd_sock, F_SETFL, O_NONBLOCK);
-  do {
+  do
+    {
     read = fread(spamd_buffer,1,sizeof(spamd_buffer),mbox_file);
-    if (read > 0) {
+    if (read > 0)
+      {
       offset = 0;
 again:
 #ifndef NO_POLL_H
@@ -274,44 +345,49 @@ again:
 
       if (result == -1 && errno == EINTR)
         goto again;
-      else if (result < 1) {
+      else if (result < 1)
+       {
         if (result == -1)
           log_write(0, LOG_MAIN|LOG_PANIC,
-            "spam acl condition: %s on spamd socket", strerror(errno));
-        else {
+            "%s %s on spamd socket", loglabel, strerror(errno));
+        else
+         {
           if (time(NULL) - start < SPAMD_TIMEOUT)
-          goto again;
+            goto again;
           log_write(0, LOG_MAIN|LOG_PANIC,
-            "spam acl condition: timed out writing spamd socket");
-        }
+            "%s timed out writing spamd socket", loglabel);
+         }
         (void)close(spamd_sock);
         (void)fclose(mbox_file);
         return DEFER;
-      }
+       }
 
       wrote = send(spamd_sock,spamd_buffer + offset,read - offset,0);
       if (wrote == -1)
-      {
-          log_write(0, LOG_MAIN|LOG_PANIC,
-            "spam acl condition: %s on spamd socket", strerror(errno));
+       {
+       log_write(0, LOG_MAIN|LOG_PANIC,
+            "%s %s on spamd socket", loglabel, strerror(errno));
         (void)close(spamd_sock);
         (void)fclose(mbox_file);
         return DEFER;
-      }
-      if (offset + wrote != read) {
+       }
+      if (offset + wrote != read)
+       {
         offset += wrote;
         goto again;
+       }
       }
     }
-  }
   while (!feof(mbox_file) && !ferror(mbox_file));
-  if (ferror(mbox_file)) {
+
+  if (ferror(mbox_file))
+    {
     log_write(0, LOG_MAIN|LOG_PANIC,
-      "spam acl condition: error reading spool file: %s", strerror(errno));
+      "%s error reading spool file: %s", loglabel, strerror(errno));
     (void)close(spamd_sock);
     (void)fclose(mbox_file);
     return DEFER;
-  }
+    }
 
   (void)fclose(mbox_file);
 
@@ -322,116 +398,142 @@ again:
    */
   memset(spamd_buffer, 0, sizeof(spamd_buffer));
   offset = 0;
-  while((i = ip_recv(spamd_sock,
+  while ((i = ip_recv(spamd_sock,
                      spamd_buffer + offset,
                      sizeof(spamd_buffer) - offset - 1,
-                     SPAMD_TIMEOUT - time(NULL) + start)) > 0 ) {
+                     SPAMD_TIMEOUT - time(NULL) + start)) > 0 )
     offset += i;
-  }
 
   /* error handling */
-  if((i <= 0) && (errno != 0)) {
+  if (i <= 0 && errno != 0)
+    {
     log_write(0, LOG_MAIN|LOG_PANIC,
-         "spam acl condition: error reading from spamd socket: %s", strerror(errno));
+         "%s error reading from spamd socket: %s", loglabel, strerror(errno));
     (void)close(spamd_sock);
     return DEFER;
-  }
+    }
 
   /* reading done */
   (void)close(spamd_sock);
 
-  /* dig in the spamd output and put the report in a multiline header, if requested */
-  if( sscanf(CS spamd_buffer,"SPAMD/%7s 0 EX_OK\r\nContent-length: %*u\r\n\r\n%lf/%lf\r\n%n",
-             spamd_version,&spamd_score,&spamd_threshold,&spamd_report_offset) != 3 ) {
+  if (is_rspamd)
+    {                          /* rspamd variant of reply */
+    int r;
+    if ((r = sscanf(CS spamd_buffer,
+           "RSPAMD/%7s 0 EX_OK\r\nMetric: default; %7s %lf / %lf / %lf\r\n%n",
+           spamd_version, spamd_short_result, &spamd_score, &spamd_threshold,
+           &spamd_reject_score, &spamd_report_offset)) != 5)
+      {
+        log_write(0, LOG_MAIN|LOG_PANIC,
+                  "%s cannot parse spamd output: %d", loglabel, r);
+        return DEFER;
+      }
+    /* now parse action */
+    p = &spamd_buffer[spamd_report_offset];
 
-    /* try to fall back to pre-2.50 spamd output */
-    if( sscanf(CS spamd_buffer,"SPAMD/%7s 0 EX_OK\r\nSpam: %*s ; %lf / %lf\r\n\r\n%n",
-               spamd_version,&spamd_score,&spamd_threshold,&spamd_report_offset) != 3 ) {
-      log_write(0, LOG_MAIN|LOG_PANIC,
-         "spam acl condition: cannot parse spamd output");
-      return DEFER;
-    };
-  };
+    if (Ustrncmp(p, "Action: ", sizeof("Action: ") - 1) == 0)
+      {
+      p += sizeof("Action: ") - 1;
+      q = &spam_action_buffer[0];
+      while (*p && *p != '\r' && (q - spam_action_buffer) < sizeof(spam_action_buffer) - 1)
+        *q++ = *p++;
+      *q = '\0';
+      }
+    }
+  else
+    {                          /* spamassassin */
+    /* dig in the spamd output and put the report in a multiline header,
+    if requested */
+    if (sscanf(CS spamd_buffer,
+        "SPAMD/%7s 0 EX_OK\r\nContent-length: %*u\r\n\r\n%lf/%lf\r\n%n",
+        spamd_version,&spamd_score,&spamd_threshold,&spamd_report_offset) != 3)
+      {
+        /* try to fall back to pre-2.50 spamd output */
+        if (sscanf(CS spamd_buffer,
+            "SPAMD/%7s 0 EX_OK\r\nSpam: %*s ; %lf / %lf\r\n\r\n%n",
+            spamd_version,&spamd_score,&spamd_threshold,&spamd_report_offset) != 3)
+          {
+         log_write(0, LOG_MAIN|LOG_PANIC,
+                   "%s cannot parse spamd output", loglabel);
+         return DEFER;
+          }
+      }
+
+    Ustrcpy(spam_action_buffer,
+      spamd_score >= spamd_threshold ? "reject" : "no action");
+    }
 
   /* Create report. Since this is a multiline string,
   we must hack it into shape first */
   p = &spamd_buffer[spamd_report_offset];
   q = spam_report_buffer;
-  while (*p != '\0') {
+  while (*p != '\0')
+    {
     /* skip \r */
-    if (*p == '\r') {
+    if (*p == '\r')
+      {
       p++;
       continue;
-    };
-    *q = *p;
-    q++;
-    if (*p == '\n') {
+      }
+    *q++ = *p;
+    if (*p++ == '\n')
+      {
       /* add an extra space after the newline to ensure
       that it is treated as a header continuation line */
-      *q = ' ';
-      q++;
-    };
-    p++;
-  };
+      *q++ = ' ';
+      }
+    }
   /* NULL-terminate */
-  *q = '\0';
-  q--;
+  *q-- = '\0';
   /* cut off trailing leftovers */
-  while (*q <= ' ') {
-    *q = '\0';
-    q--;
-  };
+  while (*q <= ' ')
+    *q-- = '\0';
+
   spam_report = spam_report_buffer;
+  spam_action = spam_action_buffer;
 
   /* create spam bar */
   spamd_score_char = spamd_score > 0 ? '+' : '-';
   j = abs((int)(spamd_score));
   i = 0;
-  if( j != 0 ) {
-    while((i < j) && (i <= MAX_SPAM_BAR_CHARS))
+  if (j != 0)
+    while ((i < j) && (i <= MAX_SPAM_BAR_CHARS))
        spam_bar_buffer[i++] = spamd_score_char;
-  }
-  else{
+  else
+    {
     spam_bar_buffer[0] = '/';
     i = 1;
-  }
+    }
   spam_bar_buffer[i] = '\0';
   spam_bar = spam_bar_buffer;
 
   /* create "float" spam score */
-  (void)string_format(spam_score_buffer, sizeof(spam_score_buffer),"%.1f", spamd_score);
+  (void)string_format(spam_score_buffer, sizeof(spam_score_buffer),
+         "%.1f", spamd_score);
   spam_score = spam_score_buffer;
 
   /* create "int" spam score */
   j = (int)((spamd_score + 0.001)*10);
-  (void)string_format(spam_score_int_buffer, sizeof(spam_score_int_buffer), "%d", j);
+  (void)string_format(spam_score_int_buffer, sizeof(spam_score_int_buffer),
+         "%d", j);
   spam_score_int = spam_score_int_buffer;
 
   /* compare threshold against score */
-  if (spamd_score >= spamd_threshold) {
-    /* spam as determined by user's threshold */
-    spam_rc = OK;
-  }
-  else {
-    /* not spam */
-    spam_rc = FAIL;
-  };
+  spam_rc = spamd_score >= spamd_threshold
+    ? OK       /* spam as determined by user's threshold */
+    : FAIL;    /* not spam */
 
   /* remember expanded spamd_address if needed */
-  if (spamd_address_work != spamd_address) {
+  if (spamd_address_work != spamd_address)
     prev_spamd_address_work = string_copy(spamd_address_work);
-  }
+
   /* remember user name and "been here" for it */
   Ustrcpy(prev_user_name, user_name);
   spam_ok = 1;
 
-  if (override) {
-    /* always return OK, no matter what the score */
-    return OK;
-  }
-  else {
-    return spam_rc;
-  };
+  return override
+    ? OK               /* always return OK, no matter what the score */
+    : spam_rc;
 }
 
 #endif