Add time, weight and backup modifiers to spamd_address list elements. Bug 670

Heavy refactoring by JH.
Also support mixed/multiple Unix/TCP server specifications.

4 files changed, 626 insertions, 449 deletions

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 13d903b16..e34ed8054 100644
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -30756,26 +30756,44 @@ spamd_address = 127.0.0.1 11333 variant=rspamd
 
 As of version 2.60, &%SpamAssassin%& also supports communication over UNIX
 sockets. If you want to us these, supply &%spamd_address%& with an absolute
-file name instead of a address/port pair:
+file name instead of an address/port pair:
 .code
 spamd_address = /var/run/spamd_socket
 .endd
 You can have multiple &%spamd%& servers to improve scalability. These can
 reside on other hardware reachable over the network. To specify multiple
 &%spamd%& servers, put multiple address/port pairs in the &%spamd_address%&
-option, separated with colons:
+option, separated with colons (the separator can be changed in the usual way):
 .code
 spamd_address = 192.168.2.10 783 : \
                 192.168.2.11 783 : \
                 192.168.2.12 783
 .endd
-Up to 32 &%spamd%& servers are supported. The servers are queried in a random
-fashion. When a server fails to respond to the connection attempt, all other
+Up to 32 &%spamd%& servers are supported.
+When a server fails to respond to the connection attempt, all other
 servers are tried until one succeeds. If no server responds, the &%spam%&
 condition defers.
 
-&*Warning*&: It is not possible to use the UNIX socket connection method with
-multiple &%spamd%& servers.
+.new
+Unix and TCP socket specifications may be mixed in any order.
+Each element of the list is a list itself, space-separated by default
+and changeable in the usual way.
+Elements after the first for Unix sockets, or second for TCP socket,
+are options.
+The supported option are:
+.code
+variant=rspamd      Use Rspamd rather than SpamAssassin protocol
+time=<start>-<end>  Use only between these times of day
+weight=<value>      Selection bias
+backup              Use only if all non-backup servers fail
+.endd
+
+Time specifications for the &`time`& option are <hour>.<minute>.<second>
+in the local time zone; each element being one or more digits.
+
+Servers are queried in a random fashion, weighted by the selection bias.
+The default value for selection bias is 1.
+.wen
 
 The &%spamd_address%& variable is expanded before use if it starts with
 a dollar sign. In this case, the expansion may return a string that is
diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog
index 835417ff2..e06ac6065 100644
--- a/doc/doc-txt/ChangeLog
+++ b/doc/doc-txt/ChangeLog
@@ -53,6 +53,13 @@ JH/13 Bug 344: The verify = reverse_host_lookup ACL condition now accepts a
 JH/14 Bug 1573: The spam= ACL condition now additionally supports Rspamd.
       Patch from Andrew Lewis.
 
+JH/15 Bug 670: The spamd_address main option (for the spam= ACL condition)
+      now supports optional time-restrictions, weighting, and backup-only
+      modifiers per server.  Patch originally by <rommer@active.by>.
+
+JH/16 The spamd_address main option now supports a mixed list of local
+      and remote servers.
+
 
 
 Exim version 4.85
diff --git a/src/src/spam.c b/src/src/spam.c
index 71993fb7f..827dd3449 100644
--- a/src/src/spam.c
+++ b/src/src/spam.c
@@ -21,519 +21,664 @@ int spam_ok = 0;
 int spam_rc = 0;
 uschar *prev_spamd_address_work = NULL;
 
-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 = -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, spamd_reject_score;
-  int spamd_report_offset;
-  uschar *p,*q;
-  int override = 0;
-  time_t start;
-  size_t read, wrote;
-  struct sockaddr_un server;
-#ifndef NO_POLL_H
-  struct pollfd pollfd;
-#else                               /* Patch posted by Erik ? for OS X */
-  struct timeval select_tv;         /* and applied by PH */
-  fd_set select_fd;
-#endif
-  uschar *spamd_address_work;
-  static const uschar * loglabel = US"spam acl condition:";
+static const uschar * loglabel = US"spam acl condition:";
 
-  /* stop compiler warning */
-  result = 0;
-
-  /* find the username from the option list */
-  if ((user_name = string_nextinlist(&list, &sep,
-                                     user_name_buffer,
-                                     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) )
-    return FAIL;
+static int
+spamd_param_init(spamd_address_container *spamd)
+{
+/* default spamd server weight, time and backup value */
+spamd->weight = SPAMD_WEIGHT;
+spamd->is_failed = FALSE;
+spamd->is_backup = FALSE;
+return 0;
+}
 
-  /* if there is an additional option, check if it is "true" */
-  if (strcmpic(list,US"true") == 0)
-    /* in that case, always return true later */
-    override = 1;
 
-  /* expand spamd_address if needed */
-  if (*spamd_address == '$')
+static int
+spamd_param(const uschar *param, spamd_address_container *spamd)
+{
+static int timesinceday = -1;
+uschar buffer[256];
+
+/* check backup parameter */
+if (Ustrcmp(param, "backup") == 0)
+  {
+  spamd->is_backup = TRUE;
+  return 0; /* OK */
+  }
+
+/*XXX more clever parsing could discard embedded spaces? */
+
+/* check weight parameter */
+if (sscanf(param, "weight=%u", &spamd->weight))
+  {
+  if (spamd->weight == 0) /* this server disabled: skip it */
+    return 1;
+  return 0; /* OK */
+  }
+
+/* check time parameter */
+if (sscanf(param, "time=%s", buffer))
+  {
+  unsigned int start_h = 0, start_m = 0, start_s = 0;
+  unsigned int end_h = 24, end_m = 0, end_s = 0;
+  unsigned int time_start, time_end;
+  uschar *start_string;
+  uschar *end_string;
+  uschar *delimiter;
+
+  if ((delimiter = US strchr(CS buffer, '-')))
     {
-    spamd_address_work = expand_string(spamd_address);
-    if (spamd_address_work == NULL)
+    *delimiter   = '\0';
+    start_string = buffer;
+    end_string   = delimiter + 1;
+    if (sscanf(CS end_string, "%u.%u.%u", &end_h, &end_m, &end_s) == 0 ||
+      sscanf(CS start_string, "%u.%u.%u", &start_h, &start_m, &start_s) == 0)
       {
-      log_write(0, LOG_MAIN|LOG_PANIC,
-        "%s spamd_address starts with $, but expansion failed: %s",
-	loglabel, expand_string_message);
-      return DEFER;
+      log_write(0, LOG_MAIN,
+	"%s warning - invalid spamd time value: '%s'", loglabel, buffer);
+      return -1; /* syntax error */
       }
     }
   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
-     )
-    spam_ok = 0;
-
-  /* if we scanned for this username last time, just return */
-  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)
     {
-    /* error while spooling */
-    log_write(0, LOG_MAIN|LOG_PANIC,
-           "%s error while creating mbox spool file", loglabel);
-    return DEFER;
+    log_write(0, LOG_MAIN,
+    "%s warning - invalid spamd time value: '%s'", loglabel, buffer);
+    return -1; /* syntax error */
     }
 
-  start = time(NULL);
-
-  /* socket does not start with '/' -> network socket */
-  if (*spamd_address_work != '/')
+  if (timesinceday < 0)
     {
-    int num_servers = 0;
-    int current_server;
-    uschar *address = NULL;
-    uschar *spamd_address_list_ptr = spamd_address_work;
-    uschar address_buffer[256];
-    spamd_address_container * spamd_address_vector[32];
-
-    /* Check how many spamd servers we have
-       and register their addresses */
-    while ((address = string_nextinlist(&spamd_address_list_ptr, &sep,
-                                        address_buffer,
-                                        sizeof(address_buffer))) != NULL)
-      {
+    time_t now = time(NULL);
+    struct tm *tmp = localtime(&now);
+    timesinceday = tmp->tm_hour*3600 + tmp->tm_min*60 + tmp->tm_sec;
+    }
 
-      /* Potential memory leak as we never free the store. */
-      spamd_address_container *this_spamd =
-        (spamd_address_container *)store_get(sizeof(spamd_address_container));
+  time_start = start_h*3600 + start_m*60 + start_s;
+  time_end = end_h*3600 + end_m*60 + end_s;
 
-      /* Check for spamd variant */
-      this_spamd->is_rspamd = Ustrstr(address, "variant=rspamd") != NULL;
+  if (timesinceday < time_start || timesinceday >= time_end)
+    return 1; /* skip spamd server */
 
-      /* grok spamd address and port */
-      if (sscanf(CS address, "%23s %hu", this_spamd->tcp_addr, &this_spamd->tcp_port) != 2)
-        {
-        log_write(0, LOG_MAIN,
-          "%s warning - invalid spamd address: '%s'", loglabel, address);
-        continue;
-	}
+  return 0; /* OK */
+  }
 
-      spamd_address_vector[num_servers] = this_spamd;
-      if (  ++num_servers
-	 >= sizeof(spamd_address_vector)/sizeof(spamd_address_vector[0]))
-        break;
-      }
+if (Ustrcmp(param, "variant=rspamd") == 0)
+  {
+  spamd->is_rspamd = TRUE;
+  return 0;
+  }
 
-    /* check if we have at least one server */
-    if (!num_servers)
-      {
-      log_write(0, LOG_MAIN|LOG_PANIC,
-         "%s no useable spamd server addresses in spamd_address configuration option.",
-	 loglabel);
-      (void)fclose(mbox_file);
-      return DEFER;
-      }
+log_write(0, LOG_MAIN, "%s warning - invalid spamd parameter: '%s'",
+  loglabel, param);
+return -1; /* syntax error */
+}
 
-    while (num_servers > 0)
-      {
-      int i;
 
-      /* Randomly pick a server to try */
-      current_server = random_number(num_servers);
+static int
+spamd_get_server(spamd_address_container **spamds, int num_servers)
+{
+unsigned int i;
+long rnd, weights = 0;
+static BOOL srandomed = 0;
+BOOL usebackup = FALSE;
+
+for (;;)
+  {
+  /* seedup, if we have only 1 server */
+  if (num_servers == 1)
+    return (spamds[0]->is_failed ? -1 : 0);
+
+  /* init ranmod */
+  if (!srandomed)
+    {
+    struct timeval tv;
+    gettimeofday(&tv, NULL);
+    srandom((unsigned int)(tv.tv_usec/1000));
+    srandomed = TRUE;
+    }
 
-      debug_printf("trying server %s, port %u\n",
-                   spamd_address_vector[current_server]->tcp_addr,
-                   spamd_address_vector[current_server]->tcp_port);
+  /* get sum of all weights */
+  for (i = 0; i < num_servers; i++)
+    if (!spamds[i]->is_failed && spamds[i]->is_backup == usebackup)
+      weights += spamds[i]->weight;
 
-      /* contact a spamd */
-      if ((spamd_sock = ip_socket(SOCK_STREAM, AF_INET)) < 0)
-	{
-        log_write(0, LOG_MAIN|LOG_PANIC,
-           "%s error creating IP socket for spamd", loglabel);
-        (void)fclose(mbox_file);
-        return DEFER;
-	}
+  if (weights != 0)
+    break;
+  if (usebackup)	/* all servers failed (backups too) */
+    return -1;
+  usebackup = TRUE;
+  }
 
-      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;
-	}
+rnd = random() % weights;
 
-      log_write(0, LOG_MAIN|LOG_PANIC,
-         "%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));
+for (i = 0; i < num_servers; i++)
+  if (!spamds[i]->is_failed && spamds[i]->is_backup == usebackup)
+    if ((rnd -= spamds[i]->weight) < 0)
+      return i;
 
-      (void)close(spamd_sock);
+log_write(0, LOG_MAIN|LOG_PANIC,
+  "%s unknown error (memory/cpu corruption?)", loglabel);
+return -1;
+}
 
-      /* Remove the server from the list. XXX We should free the memory */
-      num_servers--;
-      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, "%s all spamd servers failed", loglabel);
-      (void)fclose(mbox_file);
-      return DEFER;
-      }
+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 = -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, spamd_reject_score;
+int spamd_report_offset;
+uschar *p,*q;
+int override = 0;
+time_t start;
+size_t read, wrote;
+struct sockaddr_un server;
+#ifndef NO_POLL_H
+struct pollfd pollfd;
+#else                               /* Patch posted by Erik ? for OS X */
+struct timeval select_tv;         /* and applied by PH */
+fd_set select_fd;
+#endif
+uschar *spamd_address_work;
+
+/* stop compiler warning */
+result = 0;
+
+/* find the username from the option list */
+if ((user_name = string_nextinlist(&list, &sep,
+				   user_name_buffer,
+				   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) )
+  return FAIL;
+
+/* if there is an additional option, check if it is "true" */
+if (strcmpic(list,US"true") == 0)
+  /* in that case, always return true later */
+  override = 1;
+
+/* expand spamd_address if needed */
+if (*spamd_address == '$')
+  {
+  spamd_address_work = expand_string(spamd_address);
+  if (spamd_address_work == NULL)
+    {
+    log_write(0, LOG_MAIN|LOG_PANIC,
+      "%s spamd_address starts with $, but expansion failed: %s",
+      loglabel, expand_string_message);
+    return DEFER;
     }
-  else
+  }
+else
+  spamd_address_work = spamd_address;
+
+HDEBUG(D_acl) debug_printf("spamd: addrlist '%s'\n", spamd_address_work);
+
+/* 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
+   )
+  spam_ok = 0;
+
+/* if we scanned for this username last time, just return */
+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)
+  {
+  /* error while spooling */
+  log_write(0, LOG_MAIN|LOG_PANIC,
+	 "%s error while creating mbox spool file", loglabel);
+  return DEFER;
+  }
+
+start = time(NULL);
+
+  {
+  int num_servers = 0;
+  int current_server;
+  uschar *address;
+  uschar *spamd_address_list_ptr = spamd_address_work;
+  spamd_address_container * spamd_address_vector[32];
+
+
+  /* Check how many spamd servers we have
+     and register their addresses */
+  while ((address = string_nextinlist(&spamd_address_list_ptr, &sep,
+				      NULL, 0)) != NULL)
     {
-    /* open the local socket */
-
-    if ((spamd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+    uschar * sublist;
+    int sublist_sep = -(int)' ';	/* default space-sep */
+    unsigned args;
+    uschar * s;
+    spamd_address_container * this_spamd =
+      (spamd_address_container *)store_get(sizeof(spamd_address_container));
+
+    HDEBUG(D_acl) debug_printf("spamd: addr entry '%s'\n", address);
+
+    for (sublist = address, args = 0, spamd_param_init(this_spamd);
+	 s = string_nextinlist(&sublist, &sublist_sep, NULL, 0);
+	 args++
+	 )
       {
-      log_write(0, LOG_MAIN|LOG_PANIC,
-                "%s spamd: unable to acquire socket (%s)",
-		loglabel,
-                strerror(errno));
-      (void)fclose(mbox_file);
-      return DEFER;
+	HDEBUG(D_acl) debug_printf("spamd: addr parm '%s'\n", s);
+	switch (args)
+	{
+	case 0:   this_spamd->hostname = s;
+		  if (*s == '/') args++;	/* local; no port */
+		  break;
+	case 1:   this_spamd->tcp_port = atoi(s); break;
+	default:  spamd_param(s, this_spamd);	 break;
+	}
       }
-
-    server.sun_family = AF_UNIX;
-
-    is_rspamd = (p = Ustrstr(spamd_address_work, "variant=rspamd")) != NULL;
-    if (is_rspamd)
+    if (args < 2)
       {
-      /* 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;
+      log_write(0, LOG_MAIN,
+	"%s warning - invalid spamd address: '%s'", loglabel, address);
+      continue;
       }
-    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,
-                "%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;
-      }
+    spamd_address_vector[num_servers] = this_spamd;
+    if (++num_servers > 31)
+      break;
     }
 
-  if (spamd_sock == -1)
+  /* check if we have at least one server */
+  if (!num_servers)
     {
     log_write(0, LOG_MAIN|LOG_PANIC,
-        "programming fault, spamd_sock unexpectedly unset");
+       "%s no useable spamd server addresses in spamd_address configuration option.",
+       loglabel);
     (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 */
-  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)
+  while (1)
     {
-    (void)close(spamd_sock);
-    log_write(0, LOG_MAIN|LOG_PANIC,
-         "%s spamd send failed: %s", loglabel, strerror(errno));
-    (void)fclose(mbox_file);
-    (void)close(spamd_sock);
-    return DEFER;
-    }
+    struct hostent *he;
+    int i;
+    spamd_address_container * this_spamd;
+    BOOL is_local;
 
-  /* now send the file */
-  /* spamd sometimes accepts conections but doesn't read data off
-   * the connection.  We make the file descriptor non-blocking so
-   * that the write will only write sufficient data without blocking
-   * and we poll the desciptor to make sure that we can write without
-   * blocking.  Short writes are gracefully handled and if the whole
-   * trasaction takes too long it is aborted.
-   * Note: poll() is not supported in OSX 10.2 and is reported to be
-   *       broken in more recent versions (up to 10.4).
-   */
-#ifndef NO_POLL_H
-  pollfd.fd = spamd_sock;
-  pollfd.events = POLLOUT;
-#endif
-  (void)fcntl(spamd_sock, F_SETFL, O_NONBLOCK);
-  do
-    {
-    read = fread(spamd_buffer,1,sizeof(spamd_buffer),mbox_file);
-    if (read > 0)
+    current_server = spamd_get_server(spamd_address_vector, num_servers);
+    this_spamd = spamd_address_vector[current_server];
+
+    is_local = *this_spamd->hostname == '/';
+
+    debug_printf(is_local
+		 ? "trying server %s\n" : "trying server %s, port %u\n",
+		 this_spamd->hostname, this_spamd->tcp_port);
+
+    /* contact a spamd */
+    if (is_local)
       {
-      offset = 0;
-again:
-#ifndef NO_POLL_H
-      result = poll(&pollfd, 1, 1000);
+      if ((spamd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
+	{
+	log_write(0, LOG_MAIN|LOG_PANIC,
+		  "%s spamd: unable to acquire socket (%s)",
+		  loglabel,
+		  strerror(errno));
+	(void)fclose(mbox_file);
+	return DEFER;
+	}
 
-/* Patch posted by Erik ? for OS X and applied by PH */
-#else
-      select_tv.tv_sec = 1;
-      select_tv.tv_usec = 0;
-      FD_ZERO(&select_fd);
-      FD_SET(spamd_sock, &select_fd);
-      result = select(spamd_sock+1, NULL, &select_fd, NULL, &select_tv);
-#endif
-/* End Erik's patch */
+      server.sun_family = AF_UNIX;
+      Ustrcpy(server.sun_path, this_spamd->hostname);
 
-      if (result == -1 && errno == EINTR)
-        goto again;
-      else if (result < 1)
+      if (connect(spamd_sock, (struct sockaddr *) &server, sizeof(struct sockaddr_un)) >= 0)
 	{
-        if (result == -1)
-          log_write(0, LOG_MAIN|LOG_PANIC,
-            "%s %s on spamd socket", loglabel, strerror(errno));
-        else
-	  {
-          if (time(NULL) - start < SPAMD_TIMEOUT)
-            goto again;
-          log_write(0, LOG_MAIN|LOG_PANIC,
-            "%s timed out writing spamd socket", loglabel);
-	  }
-        (void)close(spamd_sock);
-        (void)fclose(mbox_file);
-        return DEFER;
+	is_rspamd = this_spamd->is_rspamd;
+	break;					/* connection OK */
 	}
 
-      wrote = send(spamd_sock,spamd_buffer + offset,read - offset,0);
-      if (wrote == -1)
+      log_write(0, LOG_MAIN|LOG_PANIC,
+		"%s spamd: unable to connect to UNIX socket %s (%s)",
+		loglabel, server.sun_path, strerror(errno) );
+      }
+    else
+      {
+      if ((spamd_sock = ip_socket(SOCK_STREAM, AF_INET)) < 0)
 	{
 	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;
+	   "%s error creating IP socket for spamd", loglabel);
+	(void)fclose(mbox_file);
+	return DEFER;
 	}
-      if (offset + wrote != read)
+
+      /*XXX should we use getaddrinfo? */
+      if (!(he = gethostbyname(CS this_spamd->hostname)))
+	log_write(0, LOG_MAIN|LOG_PANIC,
+	  "%s failed to lookup host '%s'", loglabel, this_spamd->hostname);
+
+      else
 	{
-        offset += wrote;
-        goto again;
+	struct in_addr in = *(struct in_addr *) he->h_addr_list[0];
+
+	if (ip_connect(spamd_sock, AF_INET, US inet_ntoa(in),
+		       this_spamd->tcp_port, 5) > -1)
+	  {
+	  is_rspamd = this_spamd->is_rspamd;
+	  break;				/* connection OK */
+	  }
+
+	log_write(0, LOG_MAIN|LOG_PANIC,
+	   "%s warning - spamd connection to '%s', port %u failed: %s",
+	   loglabel,
+	   this_spamd->hostname, this_spamd->tcp_port, strerror(errno));
 	}
-      }
-    }
-  while (!feof(mbox_file) && !ferror(mbox_file));
 
-  if (ferror(mbox_file))
-    {
-    log_write(0, LOG_MAIN|LOG_PANIC,
-      "%s error reading spool file: %s", loglabel, strerror(errno));
-    (void)close(spamd_sock);
-    (void)fclose(mbox_file);
-    return DEFER;
+      (void)close(spamd_sock);
+
+      this_spamd->is_failed = TRUE;
+      current_server = spamd_get_server(spamd_address_vector, num_servers);
+      if (current_server < 0)
+	{
+	log_write(0, LOG_MAIN|LOG_PANIC, "%s all spamd servers failed",
+	  loglabel);
+	(void)fclose(mbox_file);
+	return DEFER;
+	}
+      }
     }
+  }
 
+if (spamd_sock == -1)
+  {
+  log_write(0, LOG_MAIN|LOG_PANIC,
+      "programming fault, spamd_sock unexpectedly unset");
   (void)fclose(mbox_file);
-
-  /* we're done sending, close socket for writing */
-  shutdown(spamd_sock,SHUT_WR);
-
-  /* read spamd response using what's left of the timeout.
-   */
-  memset(spamd_buffer, 0, sizeof(spamd_buffer));
-  offset = 0;
-  while ((i = ip_recv(spamd_sock,
-                     spamd_buffer + offset,
-                     sizeof(spamd_buffer) - offset - 1,
-                     SPAMD_TIMEOUT - time(NULL) + start)) > 0 )
-    offset += i;
-
-  /* error handling */
-  if (i <= 0 && errno != 0)
+  return DEFER;
+  }
+
+(void)fcntl(spamd_sock, F_SETFL, O_NONBLOCK);
+/* now we are connected to spamd on spamd_sock */
+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,
+       "%s spamd send failed: %s", loglabel, strerror(errno));
+  (void)fclose(mbox_file);
+  return DEFER;
+  }
+
+/* now send the file */
+/* spamd sometimes accepts conections but doesn't read data off
+ * the connection.  We make the file descriptor non-blocking so
+ * that the write will only write sufficient data without blocking
+ * and we poll the desciptor to make sure that we can write without
+ * blocking.  Short writes are gracefully handled and if the whole
+ * trasaction takes too long it is aborted.
+ * Note: poll() is not supported in OSX 10.2 and is reported to be
+ *       broken in more recent versions (up to 10.4).
+ */
+#ifndef NO_POLL_H
+pollfd.fd = spamd_sock;
+pollfd.events = POLLOUT;
+#endif
+(void)fcntl(spamd_sock, F_SETFL, O_NONBLOCK);
+do
+  {
+  read = fread(spamd_buffer,1,sizeof(spamd_buffer),mbox_file);
+  if (read > 0)
     {
-    log_write(0, LOG_MAIN|LOG_PANIC,
-         "%s error reading from spamd socket: %s", loglabel, strerror(errno));
-    (void)close(spamd_sock);
-    return DEFER;
-    }
+    offset = 0;
+again:
+#ifndef NO_POLL_H
+    result = poll(&pollfd, 1, 1000);
 
-  /* reading done */
-  (void)close(spamd_sock);
+/* Patch posted by Erik ? for OS X and applied by PH */
+#else
+    select_tv.tv_sec = 1;
+    select_tv.tv_usec = 0;
+    FD_ZERO(&select_fd);
+    FD_SET(spamd_sock, &select_fd);
+    result = select(spamd_sock+1, NULL, &select_fd, NULL, &select_tv);
+#endif
+/* End Erik's patch */
 
-  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)
+    if (result == -1 && errno == EINTR)
+      goto again;
+    else if (result < 1)
       {
-        log_write(0, LOG_MAIN|LOG_PANIC,
-                  "%s cannot parse spamd output: %d", loglabel, r);
-        return DEFER;
+      if (result == -1)
+	log_write(0, LOG_MAIN|LOG_PANIC,
+	  "%s %s on spamd socket", loglabel, strerror(errno));
+      else
+	{
+	if (time(NULL) - start < SPAMD_TIMEOUT)
+	  goto again;
+	log_write(0, LOG_MAIN|LOG_PANIC,
+	  "%s timed out writing spamd socket", loglabel);
+	}
+      (void)close(spamd_sock);
+      (void)fclose(mbox_file);
+      return DEFER;
       }
-    /* now parse action */
-    p = &spamd_buffer[spamd_report_offset];
 
-    if (Ustrncmp(p, "Action: ", sizeof("Action: ") - 1) == 0)
+    wrote = send(spamd_sock,spamd_buffer + offset,read - offset,0);
+    if (wrote == -1)
       {
-      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';
+      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;
       }
-    }
-  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)
+    if (offset + wrote != read)
       {
-        /* 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;
-          }
+      offset += wrote;
+      goto again;
       }
-
-    Ustrcpy(spam_action_buffer,
-      spamd_score >= spamd_threshold ? "reject" : "no action");
     }
+  }
+while (!feof(mbox_file) && !ferror(mbox_file));
 
-  /* Create report. Since this is a multiline string,
-  we must hack it into shape first */
+if (ferror(mbox_file))
+  {
+  log_write(0, LOG_MAIN|LOG_PANIC,
+    "%s error reading spool file: %s", loglabel, strerror(errno));
+  (void)close(spamd_sock);
+  (void)fclose(mbox_file);
+  return DEFER;
+  }
+
+(void)fclose(mbox_file);
+
+/* we're done sending, close socket for writing */
+shutdown(spamd_sock,SHUT_WR);
+
+/* read spamd response using what's left of the timeout.  */
+memset(spamd_buffer, 0, sizeof(spamd_buffer));
+offset = 0;
+while ((i = ip_recv(spamd_sock,
+		   spamd_buffer + offset,
+		   sizeof(spamd_buffer) - offset - 1,
+		   SPAMD_TIMEOUT - time(NULL) + start)) > 0 )
+  offset += i;
+
+/* error handling */
+if (i <= 0 && errno != 0)
+  {
+  log_write(0, LOG_MAIN|LOG_PANIC,
+       "%s error reading from spamd socket: %s", loglabel, strerror(errno));
+  (void)close(spamd_sock);
+  return DEFER;
+  }
+
+/* reading done */
+(void)close(spamd_sock);
+
+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];
-  q = spam_report_buffer;
-  while (*p != '\0')
+
+  if (Ustrncmp(p, "Action: ", sizeof("Action: ") - 1) == 0)
     {
-    /* skip \r */
-    if (*p == '\r')
-      {
-      p++;
-      continue;
-      }
-    *q++ = *p;
-    if (*p++ == '\n')
-      {
-      /* add an extra space after the newline to ensure
-      that it is treated as a header continuation line */
-      *q++ = ' ';
-      }
+    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';
     }
-  /* NULL-terminate */
-  *q-- = '\0';
-  /* cut off trailing leftovers */
-  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))
-       spam_bar_buffer[i++] = spamd_score_char;
-  else
+  }
+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)
     {
-    spam_bar_buffer[0] = '/';
-    i = 1;
+      /* 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;
+	}
     }
-  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);
-  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);
-  spam_score_int = spam_score_int_buffer;
-
-  /* compare threshold against score */
-  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)
-    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;
-
-  return override
-    ? OK		/* always return OK, no matter what the score */
-    : spam_rc;
+
+  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')
+  {
+  /* skip \r */
+  if (*p == '\r')
+    {
+    p++;
+    continue;
+    }
+  *q++ = *p;
+  if (*p++ == '\n')
+    {
+    /* add an extra space after the newline to ensure
+    that it is treated as a header continuation line */
+    *q++ = ' ';
+    }
+  }
+/* NULL-terminate */
+*q-- = '\0';
+/* cut off trailing leftovers */
+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))
+     spam_bar_buffer[i++] = spamd_score_char;
+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);
+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);
+spam_score_int = spam_score_int_buffer;
+
+/* compare threshold against score */
+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)
+  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;
+
+return override
+  ? OK		/* always return OK, no matter what the score */
+  : spam_rc;
 }
 
 #endif
diff --git a/src/src/spam.h b/src/src/spam.h
index e6d27a137..50aed9145 100644
--- a/src/src/spam.h
+++ b/src/src/spam.h
@@ -17,13 +17,20 @@
 
 /* SHUT_WR seems to be undefined on Unixware ? */
 #ifndef SHUT_WR
-#define SHUT_WR 1
+# define SHUT_WR 1
 #endif
 
-typedef struct spamd_address_container {
-  uschar tcp_addr[24];
-  unsigned short int tcp_port;
-  BOOL is_rspamd;
+/* default weight */
+#define SPAMD_WEIGHT 1
+
+typedef struct spamd_address_container
+{
+  uschar * hostname;
+  unsigned short tcp_port;
+  int is_rspamd:1;
+  int is_failed:1;
+  int is_backup:1;
+  unsigned int weight;
 } spamd_address_container;
 
 #endif