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 - 2009 */
   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 both 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
  36 *extra_headers = addr->p.extra_headers;
  37
  38 if (rblock->extra_headers != NULL)
  39   {
  40   header_line *h;
  41   uschar *s = expand_string(rblock->extra_headers);
  42
  43   if (s == NULL)
  44     {
  45     if (!expand_string_forcedfail)
  46       {
  47       addr->message = string_sprintf("%s router failed to expand \"%s\": %s",
  48         rblock->name, rblock->extra_headers, expand_string_message);
  49       return DEFER;
  50       }
  51     }
  52
  53   /* Expand succeeded. Put extra header at the start of the chain because
  54   further down it may point to headers from other routers, which may be
  55   shared with other addresses. The output function outputs them in reverse
  56   order. */
  57
  58   else
  59     {
  60     int slen = Ustrlen(s);
  61     if (slen > 0)
  62       {
  63       h = store_get(sizeof(header_line));
  64
  65       /* We used to use string_sprintf() to add the newline if needed, but that
  66       causes problems if the header line is exceedingly long (e.g. adding
  67       something to a pathologically long line). So avoid it. */
  68
  69       if (s[slen-1] == '\n')
  70         {
  71         h->text = s;
  72         }
  73       else
  74         {
  75         h->text = store_get(slen+2);
  76         memcpy(h->text, s, slen);
  77         h->text[slen++] = '\n';
  78         h->text[slen] = 0;
  79         }
  80
  81       h->next = addr->p.extra_headers;
  82       h->type = htype_other;
  83       h->slen = slen;
  84       *extra_headers = h;
  85       }
  86     }
  87   }
  88
  89 /* Default is to retain existing removes */
  90
  91 *remove_headers = addr->p.remove_headers;
  92
  93 if (rblock->remove_headers != NULL)
  94   {
  95   uschar *s = expand_string(rblock->remove_headers);
  96   if (s == NULL)
  97     {
  98     if (!expand_string_forcedfail)
  99       {
 100       addr->message = string_sprintf("%s router failed to expand \"%s\": %s",
 101         rblock->name, rblock->remove_headers, expand_string_message);
 102       return DEFER;
 103       }
 104     }
 105   else if (*s != 0)
 106     {
 107     if (addr->p.remove_headers == NULL)
 108       *remove_headers = s;
 109     else
 110       *remove_headers = string_sprintf("%s : %s", addr->p.remove_headers, s);
 111     }
 112   }
 113
 114 return OK;
 115 }
 116
 117 /* End of rf_get_munge_headers.c */