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 - 2014 */
   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->p.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("%s router failed to expand \"%s\": %s",
  50           rblock->name, rblock->extra_headers, expand_string_message);
  51         return DEFER;
  52         }
  53       }
  54     else if ((slen = Ustrlen(s)) > 0)
  55       {
  56       /* Expand succeeded. Put extra headers at the start of the chain because
  57       further down it may point to headers from other routers, which may be
  58       shared with other addresses. The output function outputs them in reverse
  59       order. */
  60
  61       header_line *  h = store_get(sizeof(header_line));
  62
  63       /* We used to use string_sprintf() to add the newline if needed, but that
  64       causes problems if the header line is exceedingly long (e.g. adding
  65       something to a pathologically long line). So avoid it. */
  66
  67       if (s[slen-1] == '\n')
  68         h->text = s;
  69       else
  70         {
  71         h->text = store_get(slen+2);
  72         memcpy(h->text, s, slen);
  73         h->text[slen++] = '\n';
  74         h->text[slen] = 0;
  75         }
  76
  77       h->next = *extra_headers;
  78       h->type = htype_other;
  79       h->slen = slen;
  80       *extra_headers = h;
  81       }
  82   }
  83
  84 /* Default is to retain existing removes */
  85 *remove_headers = addr->p.remove_headers;
  86
  87 /* Expand items from colon-sep list separately, then build new list */
  88 if (rblock->remove_headers)
  89   {
  90   const uschar * list = rblock->remove_headers;
  91   int sep = ':';
  92   uschar * s;
  93
  94   while ((s = string_nextinlist(&list, &sep, NULL, 0)))
  95     if (!(s = expand_string(s)))
  96       {
  97       if (!expand_string_forcedfail)
  98         {
  99         addr->message = string_sprintf("%s router failed to expand \"%s\": %s",
 100           rblock->name, rblock->remove_headers, expand_string_message);
 101         return DEFER;
 102         }
 103       }
 104     else if (*s)
 105       *remove_headers = string_append_listele(*remove_headers, ':', s);
 106   }
 107
 108 return OK;
 109 }
 110
 111 /* End of rf_get_munge_headers.c */