Support TTL from SOA for NXDOMAIN & NODATA cache entries for dnslists. Bug 1395

[exim.git] / src / src / verify.c

diff --git a/src/src/verify.c b/src/src/verify.c
index e98dee669de84f7a15dbaeb303ffb7fa9e031b42..384739b2b3ea46383e3c4849e9c177743f3819b8 100644 (file)
--- a/src/src/verify.c
+++ b/src/src/verify.c
@@ -1001,6 +1001,26 @@ no_conn:
          string_sprintf("response to \"%s\" was: %s",
                          big_buffer, string_printing(sx.buffer));
 
          string_sprintf("response to \"%s\" was: %s",
                          big_buffer, string_printing(sx.buffer));
 

+       /* RFC 5321 section 4.2: the text portion of the response may have only
+       HT, SP, Printable US-ASCII.  Deal with awkward chars by cutting the
+       received message off before passing it onward.  Newlines are ok; they
+       just become a multiline response (but wrapped in the error code we
+       produce). */
+
+       for (uschar * s = sx.buffer;
+            *s && s < sx.buffer + sizeof(sx.buffer);
+            s++)
+         {
+         uschar c = *s;
+         if (c != '\t' && c != '\n' && (c < ' ' || c > '~'))
+           {
+           if (s - sx.buffer < sizeof(sx.buffer) - 12)
+             memcpy(s, "(truncated)", 12);
+           else
+             *s = '\0';
+           break;
+           }
+         }

        addr->user_message = options & vopt_is_recipient
          ? string_sprintf("Callout verification failed:\n%s", sx.buffer)
          : string_sprintf("Called:   %s\nSent:     %s\nResponse: %s",
        addr->user_message = options & vopt_is_recipient
          ? string_sprintf("Callout verification failed:\n%s", sx.buffer)
          : string_sprintf("Called:   %s\nSent:     %s\nResponse: %s",


@@ -1172,7 +1192,7 @@ if (!done)
 /* Come here from within the cache-reading code on fast-track exit. */
 
 END_CALLOUT:
 /* Come here from within the cache-reading code on fast-track exit. */
 
 END_CALLOUT:

-tls_modify_variables(&tls_in);
+tls_modify_variables(&tls_in); /* return variables to inbound values */

 return yield;
 }
 
 return yield;
 }
 


@@ -2193,7 +2213,7 @@ the -bv or -bt case). */
 
 out:
 verify_mode = NULL;
 
 out:
 verify_mode = NULL;

-tls_modify_variables(&tls_in);
+tls_modify_variables(&tls_in); /* return variables to inbound values */

 
 return yield;
 }
 
 return yield;
 }


@@ -2349,7 +2369,7 @@ for (header_line * h = header_list; h; h = h->next)
     if ((*s < 33) || (*s > 126))
       {
       *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",
     if ((*s < 33) || (*s > 126))
       {
       *msgptr = string_sprintf("Invalid character in header \"%.*s\" found",

-                            colon - h->text, h->text);
+                            (int)(colon - h->text), h->text);

       return FAIL;
       }
   }
       return FAIL;
       }
   }


@@ -3351,7 +3371,7 @@ one_check_dnsbl(uschar *domain, uschar *domain_txt, uschar *keydomain,
   uschar *prepend, uschar *iplist, BOOL bitmask, int match_type,
   int defer_return)
 {
   uschar *prepend, uschar *iplist, BOOL bitmask, int match_type,
   int defer_return)
 {

-dns_answer dnsa;
+dns_answer * dnsa = store_get_dns_answer();

 dns_scan dnss;
 tree_node *t;
 dnsbl_cache_block *cb;
 dns_scan dnss;
 tree_node *t;
 dnsbl_cache_block *cb;


@@ -3376,7 +3396,7 @@ if (  (t = tree_search(dnsbl_cache, query))
 /* Previous lookup was cached */
 
   {
 /* Previous lookup was cached */
 
   {

-  HDEBUG(D_dnsbl) debug_printf("using result of previous DNS lookup\n");
+  HDEBUG(D_dnsbl) debug_printf("dnslists: using result of previous lookup\n");

   }
 
 /* If not cached from a previous lookup, we must do a DNS lookup, and
   }
 
 /* If not cached from a previous lookup, we must do a DNS lookup, and


@@ -3384,7 +3404,7 @@ cache the result in permanent memory. */
 
 else
   {
 
 else
   {

-  uint ttl = 3600;
+  uint ttl = 3600;     /* max TTL for positive cache entries */

 
   store_pool = POOL_PERM;
 
 
   store_pool = POOL_PERM;
 


@@ -3404,7 +3424,7 @@ else
   /* Do the DNS lookup . */
 
   HDEBUG(D_dnsbl) debug_printf("new DNS lookup for %s\n", query);
   /* Do the DNS lookup . */
 
   HDEBUG(D_dnsbl) debug_printf("new DNS lookup for %s\n", query);

-  cb->rc = dns_basic_lookup(&dnsa, query, T_A);
+  cb->rc = dns_basic_lookup(dnsa, query, T_A);

   cb->text_set = FALSE;
   cb->text = NULL;
   cb->rhs = NULL;
   cb->text_set = FALSE;
   cb->text = NULL;
   cb->rhs = NULL;


@@ -3419,34 +3439,58 @@ else
   addresses generated in that way as well.
 
   Mark the cache entry with the "now" plus the minimum of the address TTLs,
   addresses generated in that way as well.
 
   Mark the cache entry with the "now" plus the minimum of the address TTLs,

-  or some suitably far-future time if none were found. */
+  or the RFC 2308 negative-cache value from the SOA if none were found. */

 
 

-  if (cb->rc == DNS_SUCCEED)
+  switch (cb->rc)

     {
     {

-    dns_address ** addrp = &(cb->rhs);
-    for (dns_record * rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); rr;
-         rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
-      if (rr->type == T_A)
-        {
-        dns_address *da = dns_address_from_rr(&dnsa, rr);
-        if (da)
-          {
-          *addrp = da;
-          while (da->next) da = da->next;
-          addrp = &da->next;
+    case DNS_SUCCEED:
+      {
+      dns_address ** addrp = &cb->rhs;
+      dns_address * da;
+      for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+          rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))
+       if (rr->type == T_A && (da = dns_address_from_rr(dnsa, rr)))
+         {
+         *addrp = da;
+         while (da->next) da = da->next;
+         addrp = &da->next;

          if (ttl > rr->ttl) ttl = rr->ttl;
          if (ttl > rr->ttl) ttl = rr->ttl;

-          }
-        }
+         }
+
+      if (cb->rhs)
+       {
+       cb->expiry = time(NULL) + ttl;
+       break;
+       }
+
+      /* If we didn't find any A records, change the return code. This can
+      happen when there is a CNAME record but there are no A records for what
+      it points to. */

 
 

-    /* If we didn't find any A records, change the return code. This can
-    happen when there is a CNAME record but there are no A records for what
-    it points to. */
+      cb->rc = DNS_NODATA;
+      }
+      /*FALLTHROUGH*/
+
+    case DNS_NOMATCH:
+    case DNS_NODATA:
+      {
+      /* Although there already is a neg-cache layer maintained by
+      dns_basic_lookup(), we have a dnslist cache entry allocated and
+      tree-inserted. So we may as well use it. */

 
 

-    if (!cb->rhs) cb->rc = DNS_NODATA;
+      time_t soa_negttl = dns_expire_from_soa(dnsa);
+      cb->expiry = soa_negttl ? soa_negttl : time(NULL) + ttl;
+      break;
+      }
+
+    default:
+      cb->expiry = time(NULL) + ttl;
+      break;

     }
 
     }
 

-  cb->expiry = time(NULL)+ttl;

   store_pool = old_pool;
   store_pool = old_pool;

+  HDEBUG(D_dnsbl) debug_printf("dnslists: wrote cache entry, ttl=%d\n",
+    (int)(cb->expiry - time(NULL)));

   }
 
 /* We now have the result of the DNS lookup, either newly done, or cached
   }
 
 /* We now have the result of the DNS lookup, either newly done, or cached


@@ -3457,7 +3501,7 @@ list (introduced by "&"), or a negative bitmask list (introduced by "!&").*/
 
 if (cb->rc == DNS_SUCCEED)
   {
 
 if (cb->rc == DNS_SUCCEED)
   {

-  dns_address *da = NULL;
+  dns_address * da = NULL;

   uschar *addlist = cb->rhs->address;
 
   /* For A and AAAA records, there may be multiple addresses from multiple
   uschar *addlist = cb->rhs->address;
 
   /* For A and AAAA records, there may be multiple addresses from multiple


@@ -3576,9 +3620,9 @@ if (cb->rc == DNS_SUCCEED)
   if (!cb->text_set)
     {
     cb->text_set = TRUE;
   if (!cb->text_set)
     {
     cb->text_set = TRUE;

-    if (dns_basic_lookup(&dnsa, query, T_TXT) == DNS_SUCCEED)
-      for (dns_record * rr = dns_next_rr(&dnsa, &dnss, RESET_ANSWERS); rr;
-           rr = dns_next_rr(&dnsa, &dnss, RESET_NEXT))
+    if (dns_basic_lookup(dnsa, query, T_TXT) == DNS_SUCCEED)
+      for (dns_record * rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS); rr;
+           rr = dns_next_rr(dnsa, &dnss, RESET_NEXT))

         if (rr->type == T_TXT)
          {
          int len = (rr->data)[0];
         if (rr->type == T_TXT)
          {
          int len = (rr->data)[0];


@@ -3694,7 +3738,7 @@ dns_init(FALSE, FALSE, FALSE);    /*XXX dnssec? */
 
 /* Loop through all the domains supplied, until something matches */
 
 
 /* Loop through all the domains supplied, until something matches */
 

-while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL)
+while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))))

   {
   int rc;
   BOOL bitmask = FALSE;
   {
   int rc;
   BOOL bitmask = FALSE;


@@ -3704,7 +3748,7 @@ while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
   uschar *iplist;
   uschar *key;
 
   uschar *iplist;
   uschar *key;
 

-  HDEBUG(D_dnsbl) debug_printf("DNS list check: %s\n", domain);
+  HDEBUG(D_dnsbl) debug_printf("dnslists check: %s\n", domain);

 
   /* Deal with special values that change the behaviour on defer */
 
 
   /* Deal with special values that change the behaviour on defer */
 


@@ -3758,8 +3802,7 @@ while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
   set domain_txt == domain. */
 
   domain_txt = domain;
   set domain_txt == domain. */
 
   domain_txt = domain;

-  comma = Ustrchr(domain, ',');
-  if (comma != NULL)
+  if ((comma = Ustrchr(domain, ',')))

     {
     *comma++ = 0;
     domain = comma;
     {
     *comma++ = 0;
     domain = comma;


@@ -3801,7 +3844,7 @@ while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
          acl_wherenames[where]);
       return ERROR;
       }
          acl_wherenames[where]);
       return ERROR;
       }

-    if (sender_host_address == NULL) return FAIL;    /* can never match */
+    if (!sender_host_address) return FAIL;    /* can never match */

     if (revadd[0] == 0) invert_address(revadd, sender_host_address);
     rc = one_check_dnsbl(domain, domain_txt, sender_host_address, revadd,
       iplist, bitmask, match_type, defer_return);
     if (revadd[0] == 0) invert_address(revadd, sender_host_address);
     rc = one_check_dnsbl(domain, domain_txt, sender_host_address, revadd,
       iplist, bitmask, match_type, defer_return);


@@ -3823,11 +3866,9 @@ while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
     int keysep = 0;
     BOOL defer = FALSE;
     uschar *keydomain;
     int keysep = 0;
     BOOL defer = FALSE;
     uschar *keydomain;

-    uschar keybuffer[256];

     uschar keyrevadd[128];
 
     uschar keyrevadd[128];
 

-    while ((keydomain = string_nextinlist(CUSS &key, &keysep, keybuffer,
-            sizeof(keybuffer))) != NULL)
+    while ((keydomain = string_nextinlist(CUSS &key, &keysep, NULL, 0)))

       {
       uschar *prepend = keydomain;
 
       {
       uschar *prepend = keydomain;
 


@@ -3839,7 +3880,6 @@ while ((domain = string_nextinlist(&list, &sep, buffer, sizeof(buffer))) != NULL
 
       rc = one_check_dnsbl(domain, domain_txt, keydomain, prepend, iplist,
         bitmask, match_type, defer_return);
 
       rc = one_check_dnsbl(domain, domain_txt, keydomain, prepend, iplist,
         bitmask, match_type, defer_return);

-

       if (rc == OK)
         {
         dnslist_domain = string_copy(domain_txt);
       if (rc == OK)
         {
         dnslist_domain = string_copy(domain_txt);