src/src/routers/rf_get_munge_headers.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2015 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 #include "../exim.h"
   9 #include "rf_functions.h"
  10
  11
  12 /*************************************************
  13 *      Get additional headers for a router       *
  14 *************************************************/
  15
  16 /* This function is called by routers to sort out the additional headers
  17 and header remove list for a particular address.
  18
  19 Arguments:
  20   addr           the input address
  21   rblock         the router instance
  22   extra_headers  points to where to hang the header chain
  23   remove_headers points to where to hang the remove list
  24
  25 Returns:         OK if no problem
  26                  DEFER if expanding a string caused a deferment
  27                    or a big disaster (e.g. expansion failure)
  28 */
  29
  30 int
  31 rf_get_munge_headers(address_item *addr, router_instance *rblock,
  32   header_line **extra_headers, uschar **remove_headers)
  33 {
  34 /* Default is to retain existing headers */
  35 *extra_headers = addr->prop.extra_headers;
  36
  37 if (rblock->extra_headers)
  38   {
  39   const uschar * list = rblock->extra_headers;
  40   int sep = '\n';
  41   uschar * s;
  42   int slen;
  43
  44   while ((s = string_nextinlist(&list, &sep, NULL, 0)))
  45     if (!(s = expand_string(s)))
  46       {
  47       if (!expand_string_forcedfail)
  48         {
  49         addr->message = string_sprintf(
  50           "%s router failed to expand add_headers item \"%s\": %s",
  51           rblock->name, s, expand_string_message);
  52         return DEFER;
  53         }
  54       }
  55     else if ((slen = Ustrlen(s)) > 0)
  56       {
  57       /* Expand succeeded. Put extra headers at the start of the chain because
  58       further down it may point to headers from other routers, which may be
  59       shared with other addresses. The output function outputs them in reverse
  60       order. */
  61
  62       header_line *  h = store_get(sizeof(header_line));
  63
  64       /* We used to use string_sprintf() to add the newline if needed, but that
  65       causes problems if the header line is exceedingly long (e.g. adding
  66       something to a pathologically long line). So avoid it. */
  67
  68       if (s[slen-1] == '\n')
  69         h->text = s;
  70       else
  71         {
  72         h->text = store_get(slen+2);
  73         memcpy(h->text, s, slen);
  74         h->text[slen++] = '\n';
  75         h->text[slen] = 0;
  76         }
  77
  78       h->next = *extra_headers;
  79       h->type = htype_other;
  80       h->slen = slen;
  81       *extra_headers = h;
  82       }
  83   }
  84
  85 /* Default is to retain existing removes */
  86 *remove_headers = addr->prop.remove_headers;
  87
  88 /* Expand items from colon-sep list separately, then build new list */
  89 if (rblock->remove_headers)
  90   {
  91   const uschar * list = rblock->remove_headers;
  92   int sep = ':';
  93   uschar * s;
  94
  95   while ((s = string_nextinlist(&list, &sep, NULL, 0)))
  96     if (!(s = expand_string(s)))
  97       {
  98       if (!expand_string_forcedfail)
  99         {
 100         addr->message = string_sprintf(
 101           "%s router failed to expand remove_headers item \"%s\": %s",
 102           rblock->name, s, expand_string_message);
 103         return DEFER;
 104         }
 105       }
 106     else if (*s)
 107       *remove_headers = string_append_listele(*remove_headers, ':', s);
 108   }
 109
 110 return OK;
 111 }
 112
 113 /* vi: aw ai sw=4
 114 */
 115 /* End of rf_get_munge_headers.c */