X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/97696d5986bd0e129a01d63b69a04aa7141a82bd..542bc632dd2ab452f87e0304e3356534e49f71f3:/src/src/lookups/dnsdb.c

diff --git a/src/src/lookups/dnsdb.c b/src/src/lookups/dnsdb.c
index 169fd67f1..0bbc86a56 100644
--- a/src/src/lookups/dnsdb.c
+++ b/src/src/lookups/dnsdb.c
@@ -1,15 +1,12 @@
-/* $Cambridge: exim/src/src/lookups/dnsdb.c,v 1.13 2005/06/10 13:38:06 tom Exp $ */
-
 /*************************************************
 *     Exim - an Internet mail transport agent    *
 *************************************************/
 
-/* Copyright (c) University of Cambridge 1995 - 2005 */
+/* Copyright (c) University of Cambridge 1995 - 2012 */
 /* See the file NOTICE for conditions of use and distribution. */
 
 #include "../exim.h"
 #include "lf_functions.h"
-#include "dnsdb.h"
 
 
 
@@ -20,9 +17,14 @@ header files. */
 #define T_TXT 16
 #endif
 
+/* Many systems do not have T_SPF. */
+#ifndef T_SPF
+#define T_SPF 99
+#endif
+
 /* Table of recognized DNS record types and their integer values. */
 
-static char *type_names[] = {
+static const char *type_names[] = {
   "a",
 #if HAVE_IPV6
   "aaaa",
@@ -36,6 +38,7 @@ static char *type_names[] = {
   "mxh",
   "ns",
   "ptr",
+  "spf",
   "srv",
   "txt",
   "zns"
@@ -55,6 +58,7 @@ static int type_values[] = {
   T_MXH,     /* Private type for "MX hostnames" */
   T_NS,
   T_PTR,
+  T_SPF,
   T_SRV,
   T_TXT,
   T_ZNS      /* Private type for "zone nameservers" */
@@ -67,7 +71,7 @@ static int type_values[] = {
 
 /* See local README for interface description. */
 
-void *
+static void *
 dnsdb_open(uschar *filename, uschar **errmsg)
 {
 filename = filename;   /* Keep picky compilers happy */
@@ -88,21 +92,28 @@ consist of a number of parts.
 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.  Similarly for "SPF" records, but the default for joining multiple
+items in one SPF record is the empty string, for direct concatenation.
+
+(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'.
 
-(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".
 
-(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. */
 
-int
+static int
 dnsdb_find(void *handle, uschar *filename, uschar *keystring, int length,
   uschar **result, uschar **errmsg, BOOL *do_cache)
 {
@@ -111,9 +122,10 @@ int size = 256;
 int ptr = 0;
 int sep = 0;
 int defer_mode = PASS;
-int type = T_TXT;
+int type;
 int failrc = FAIL;
 uschar *outsep = US"\n";
+uschar *outsep2 = NULL;
 uschar *equals, *domain, *found;
 uschar buffer[256];
 
@@ -131,13 +143,24 @@ filename = filename;
 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;
+  if (*keystring == ',')
+    {
+    outsep2 = keystring + 1;
+    keystring += 2;
+    }
+  else if (*keystring == ';')
+    {
+    outsep2 = US"";
+    keystring++;
+    }
   while (isspace(*keystring)) keystring++;
   }
 
@@ -175,8 +198,10 @@ if (strncmpic(keystring, US"defer_", 6) == 0)
   while (isspace(*keystring)) keystring++;
   }
 
-/* If the keystring contains an = this must be preceded by a valid type name. */
+/* Figure out the "type" value if it is not T_TXT.
+If the keystring contains an = this must be preceded by a valid type name. */
 
+type = T_TXT;
 if ((equals = Ustrchr(keystring, '=')) != NULL)
   {
   int i, len;
@@ -221,9 +246,17 @@ 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] != '<' &&
-    string_is_ip_address(keystring, NULL) > 0)
+    string_is_ip_address(keystring, NULL) != 0)
   sep = -1;
 
+/* SPF strings should be concatenated without a separator, thus make
+it the default if not defined (see RFC 4408 section 3.1.3).
+Multiple SPF records are forbidden (section 3.1.2) but are currently
+not handled specially, thus they are concatenated with \n by default. */
+
+if (type == T_SPF && outsep2 == NULL)
+  outsep2 = US"";
+
 /* Now scan the list and do a lookup for each item */
 
 while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
@@ -241,7 +274,7 @@ 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) &&
-      string_is_ip_address(domain, NULL) > 0)
+      string_is_ip_address(domain, NULL) != 0)
     {
     dns_build_reverse(domain, rbuffer);
     domain = rbuffer;
@@ -249,13 +282,13 @@ while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
 
   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);
@@ -301,10 +334,28 @@ while ((domain = string_nextinlist(&keystring, &sep, buffer, sizeof(buffer)))
 
     if (ptr != 0) yield = string_cat(yield, &size, &ptr, outsep, 1);
 
-    if (type == T_TXT)
+    if (type == T_TXT || type == T_SPF)
       {
-      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 */
       {
@@ -394,4 +445,42 @@ yield[ptr] = 0;
 return OK;
 }
 
+
+
+/*************************************************
+*         Version reporting entry point          *
+*************************************************/
+
+/* See local README for interface description. */
+
+#include "../version.h"
+
+void
+dnsdb_version_report(FILE *f)
+{
+#ifdef DYNLOOKUP
+fprintf(f, "Library version: DNSDB: Exim version %s\n", EXIM_VERSION_STR);
+#endif
+}
+
+
+static lookup_info _lookup_info = {
+  US"dnsdb",                     /* lookup name */
+  lookup_querystyle,             /* query style */
+  dnsdb_open,                    /* open function */
+  NULL,                          /* check function */
+  dnsdb_find,                    /* find function */
+  NULL,                          /* no close function */
+  NULL,                          /* no tidy function */
+  NULL,                          /* no quoting function */
+  dnsdb_version_report           /* version reporting */
+};
+
+#ifdef DYNLOOKUP
+#define dnsdb_lookup_module_info _lookup_module_info
+#endif
+
+static lookup_info *_lookup_list[] = { &_lookup_info };
+lookup_module_info dnsdb_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 };
+
 /* End of lookups/dnsdb.c */