DKIM DNS TXT record bug fix. Fixes: #967

[exim.git] / src / src / lookups / dnsdb.c

diff --git a/src/src/lookups/dnsdb.c b/src/src/lookups/dnsdb.c
index 17bffba42fc87faf76ad51cc0e4747ed9d4f7025..89ad67d286bb39232568c89921fe0d9d021b7aa6 100644 (file)
--- a/src/src/lookups/dnsdb.c
+++ b/src/src/lookups/dnsdb.c
@@ -1,10 +1,10 @@
-/* $Cambridge: exim/src/src/lookups/dnsdb.c,v 1.12 2005/06/10 13:29:36 tom Exp $ */
+/* $Cambridge: exim/src/src/lookups/dnsdb.c,v 1.20 2010/05/29 19:23:26 nm4 Exp $ */

 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
 
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 

-/* Copyright (c) University of Cambridge 1995 - 2005 */
+/* Copyright (c) University of Cambridge 1995 - 2009 */

 /* See the file NOTICE for conditions of use and distribution. */
 
 #include "../exim.h"
 /* See the file NOTICE for conditions of use and distribution. */
 
 #include "../exim.h"


@@ -88,17 +88,23 @@ consist of a number of parts.
 separator character that is used when multiple records are found. The default
 separator is newline.
 
 separator character that is used when multiple records are found. The default
 separator is newline.
 

-(b) If the next sequence of characters is 'defer_FOO' followed by a comma,
+(b) If the next character is ',' then the next character is the separator
+character used for multiple items of text in "TXT" records. Alternatively,
+if the next character is ';' then these multiple items are concatenated with
+no separator. With neither of these options specified, only the first item
+is output.
+
+(c) If the next sequence of characters is 'defer_FOO' followed by a comma,

 the defer behaviour is set to FOO. The possible behaviours are: 'strict', where
 any defer causes the whole lookup to defer; 'lax', where a defer causes the
 whole lookup to defer only if none of the DNS queries succeeds; and 'never',
 where all defers are as if the lookup failed. The default is 'lax'.
 
 the defer behaviour is set to FOO. The possible behaviours are: 'strict', where
 any defer causes the whole lookup to defer; 'lax', where a defer causes the
 whole lookup to defer only if none of the DNS queries succeeds; and 'never',
 where all defers are as if the lookup failed. The default is 'lax'.
 

-(c) If the next sequence of characters is a sequence of letters and digits
+(d) If the next sequence of characters is a sequence of letters and digits

 followed by '=', it is interpreted as the name of the DNS record type. The
 default is "TXT".
 
 followed by '=', it is interpreted as the name of the DNS record type. The
 default is "TXT".
 

-(d) Then there follows list of domain names. This is a generalized Exim list,
+(e) Then there follows list of domain names. This is a generalized Exim list,

 which may start with '<' in order to set a specific separator. The default
 separator, as always, is colon. */
 
 which may start with '<' in order to set a specific separator. The default
 separator, as always, is colon. */
 


@@ -114,6 +120,7 @@ int defer_mode = PASS;
 int type = T_TXT;
 int failrc = FAIL;
 uschar *outsep = US"\n";
 int type = T_TXT;
 int failrc = FAIL;
 uschar *outsep = US"\n";

+uschar *outsep2 = NULL;

 uschar *equals, *domain, *found;
 uschar buffer[256];
 
 uschar *equals, *domain, *found;
 uschar buffer[256];
 


@@ -131,13 +138,24 @@ filename = filename;
 length = length;
 do_cache = do_cache;
 
 length = length;
 do_cache = do_cache;
 

-/* If the string starts with '>' we change the output separator */
+/* If the string starts with '>' we change the output separator.
+If it's followed by ';' or ',' we set the TXT output separator. */

 
 while (isspace(*keystring)) keystring++;
 if (*keystring == '>')
   {
   outsep = keystring + 1;
   keystring += 2;
 
 while (isspace(*keystring)) keystring++;
 if (*keystring == '>')
   {
   outsep = keystring + 1;
   keystring += 2;

+  if (*keystring == ',')
+    {
+    outsep2 = keystring + 1;
+    keystring += 2;
+    }
+  else if (*keystring == ';')
+    {
+    outsep2 = US"";
+    keystring++;
+    }

   while (isspace(*keystring)) keystring++;
   }
 
   while (isspace(*keystring)) keystring++;
   }
 


@@ -221,7 +239,7 @@ remaining string is valid as an IP address, set an impossible separator so that
 it is treated as one item. */
 
 if (type == T_PTR && keystring[0] != '<' &&
 it is treated as one item. */
 
 if (type == T_PTR && keystring[0] != '<' &&

-    string_is_ip_address(keystring, NULL) > 0)
+    string_is_ip_address(keystring, NULL) != 0)

   sep = -1;
 
 /* Now scan the list and do a lookup for each item */
   sep = -1;
 
 /* Now scan the list and do a lookup for each item */


@@ -241,7 +259,7 @@ while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
   doing the reversal is now in a separate function. */
 
   if ((type == T_PTR || type == T_CSA) &&
   doing the reversal is now in a separate function. */
 
   if ((type == T_PTR || type == T_CSA) &&

-      string_is_ip_address(domain, NULL) > 0)
+      string_is_ip_address(domain, NULL) != 0)

     {
     dns_build_reverse(domain, rbuffer);
     domain = rbuffer;
     {
     dns_build_reverse(domain, rbuffer);
     domain = rbuffer;


@@ -249,19 +267,17 @@ while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
 
   DEBUG(D_lookup) debug_printf("dnsdb key: %s\n", domain);
 
 
   DEBUG(D_lookup) debug_printf("dnsdb key: %s\n", domain);
 

-  /* Do the lookup and sort out the result. There are two special types that
-  are handled specially: T_ZNS and T_MXH. The former is handled in a special
-  lookup function so that the facility could be used from other parts of the
-  Exim code. The latter affects only what happens later on in this function,
-  but for tidiness it is handled in a similar way. If the lookup fails,
-  continue with the next domain. In the case of DEFER, adjust the final
-  "nothing found" result, but carry on to the next domain. */
+  /* Do the lookup and sort out the result. There are three special types that
+  are handled specially: T_CSA, T_ZNS and T_MXH. The former two are handled in
+  a special lookup function so that the facility could be used from other
+  parts of the Exim code. The latter affects only what happens later on in
+  this function, but for tidiness it is handled in a similar way. If the
+  lookup fails, continue with the next domain. In the case of DEFER, adjust
+  the final "nothing found" result, but carry on to the next domain. */

 
   found = domain;
   rc = dns_special_lookup(&dnsa, domain, type, &found);
 
 
   found = domain;
   rc = dns_special_lookup(&dnsa, domain, type, &found);
 

-  DEBUG(D_lookup) debug_printf("Back in dnsdb_find\n");
-

   if (rc == DNS_NOMATCH || rc == DNS_NODATA) continue;
   if (rc != DNS_SUCCEED)
     {
   if (rc == DNS_NOMATCH || rc == DNS_NODATA) continue;
   if (rc != DNS_SUCCEED)
     {


@@ -305,8 +321,26 @@ while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
 
     if (type == T_TXT)
       {
 
     if (type == T_TXT)
       {

-      yield = string_cat(yield, &size, &ptr, (uschar *)(rr->data+1),
-        (rr->data)[0]);
+      if (outsep2 == NULL)
+        {
+        /* output only the first item of data */
+        yield = string_cat(yield, &size, &ptr, (uschar *)(rr->data+1),
+          (rr->data)[0]);
+        }
+      else
+        {
+        /* output all items */
+        int data_offset = 0;
+        while (data_offset < rr->size)
+          {
+          uschar chunk_len = (rr->data)[data_offset++];
+          if (outsep2[0] != '\0' && data_offset != 1)
+            yield = string_cat(yield, &size, &ptr, outsep2, 1);
+          yield = string_cat(yield, &size, &ptr,
+                             (uschar *)((rr->data)+data_offset), chunk_len);
+          data_offset += chunk_len;
+          }
+        }

       }
     else   /* T_CNAME, T_CSA, T_MX, T_MXH, T_NS, T_PTR, T_SRV */
       {
       }
     else   /* T_CNAME, T_CSA, T_MX, T_MXH, T_NS, T_PTR, T_SRV */
       {