Fix segfault on bad cmdline -f (sender) argument. Bug 2541

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

diff --git a/src/src/verify.c b/src/src/verify.c
index 4422b4ad109bed885ca8063ab25c4db237f289b9..7b9d006f6ecd50236a37ed5b8282820913d15d10 100644 (file)
--- a/src/src/verify.c
+++ b/src/src/verify.c
@@ -574,6 +574,7 @@ else
   {
   smtp_transport_options_block *ob =
     (smtp_transport_options_block *)addr->transport->options_block;
   {
   smtp_transport_options_block *ob =
     (smtp_transport_options_block *)addr->transport->options_block;

+  smtp_context * sx = NULL;

 
   /* The information wasn't available in the cache, so we have to do a real
   callout and save the result in the cache for next time, unless no_cache is set,
 
   /* The information wasn't available in the cache, so we have to do a real
   callout and save the result in the cache for next time, unless no_cache is set,


@@ -586,6 +587,10 @@ else
       log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
         "callout_random_local_part: %s", expand_string_message);
 
       log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand "
         "callout_random_local_part: %s", expand_string_message);
 

+  /* Compile regex' used by client-side smtp */
+
+  smtp_deliver_init();
+

   /* Default the connect and overall callout timeouts if not set, and record the
   time we are starting so that we can enforce it. */
 
   /* Default the connect and overall callout timeouts if not set, and record the
   time we are starting so that we can enforce it. */
 


@@ -625,8 +630,7 @@ coding means skipping this whole loop and doing the append separately.  */
     {
     int host_af;
     int port = 25;
     {
     int host_af;
     int port = 25;

-    uschar *interface = NULL;  /* Outgoing interface to use; NULL => any */
-    smtp_context sx;
+    uschar * interface = NULL;  /* Outgoing interface to use; NULL => any */

 
     if (!host->address)
       {
 
     if (!host->address)
       {


@@ -666,14 +670,17 @@ coding means skipping this whole loop and doing the append separately.  */
       log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
         addr->message);
 
       log_write(0, LOG_MAIN|LOG_PANIC, "<%s>: %s", addr->address,
         addr->message);
 

-    sx.addrlist = addr;
-    sx.conn_args.host = host;
-    sx.conn_args.host_af = host_af,
-    sx.port = port;
-    sx.conn_args.interface = interface;
-    sx.helo_data = tf->helo_data;
-    sx.conn_args.tblock = addr->transport;
-    sx.verify = TRUE;
+    if (!sx) sx = store_get(sizeof(*sx), TRUE);        /* tainted buffers */
+    memset(sx, 0, sizeof(*sx));
+
+    sx->addrlist = addr;
+    sx->conn_args.host = host;
+    sx->conn_args.host_af = host_af,
+    sx->port = port;
+    sx->conn_args.interface = interface;
+    sx->helo_data = tf->helo_data;
+    sx->conn_args.tblock = addr->transport;
+    sx->verify = TRUE;

 
 tls_retry_connection:
     /* Set the address state so that errors are recorded in it */
 
 tls_retry_connection:
     /* Set the address state so that errors are recorded in it */


@@ -686,7 +693,7 @@ tls_retry_connection:
     SMTP command to send.  If we tried TLS but it failed, try again without
     if permitted */
 
     SMTP command to send.  If we tried TLS but it failed, try again without
     if permitted */
 

-    yield = smtp_setup_conn(&sx, FALSE);
+    yield = smtp_setup_conn(sx, FALSE);

 #ifndef DISABLE_TLS
     if (  yield == DEFER
        && addr->basic_errno == ERRNO_TLSFAILURE
 #ifndef DISABLE_TLS
     if (  yield == DEFER
        && addr->basic_errno == ERRNO_TLSFAILURE


@@ -698,7 +705,7 @@ tls_retry_connection:
        "%s: callout unencrypted to %s [%s] (not in hosts_require_tls)",
        addr->message, host->name, host->address);
       addr->transport_return = PENDING_DEFER;
        "%s: callout unencrypted to %s [%s] (not in hosts_require_tls)",
        addr->message, host->name, host->address);
       addr->transport_return = PENDING_DEFER;

-      yield = smtp_setup_conn(&sx, TRUE);
+      yield = smtp_setup_conn(sx, TRUE);

       }
 #endif
     if (yield != OK)
       }
 #endif
     if (yield != OK)


@@ -728,11 +735,11 @@ tls_retry_connection:
     addr->authenticator = client_authenticator;
     addr->auth_id = client_authenticated_id;
 
     addr->authenticator = client_authenticator;
     addr->auth_id = client_authenticated_id;
 

-    sx.from_addr = from_address;
-    sx.first_addr = sx.sync_addr = addr;
-    sx.ok = FALSE;                     /*XXX these 3 last might not be needed for verify? */
-    sx.send_rset = TRUE;
-    sx.completed_addr = FALSE;
+    sx->from_addr = from_address;
+    sx->first_addr = sx->sync_addr = addr;
+    sx->ok = FALSE;                    /*XXX these 3 last might not be needed for verify? */
+    sx->send_rset = TRUE;
+    sx->completed_addr = FALSE;

 
     new_domain_record.result = old_domain_cache_result == ccache_reject_mfnull
       ? ccache_reject_mfnull : ccache_accept;
 
     new_domain_record.result = old_domain_cache_result == ccache_reject_mfnull
       ? ccache_reject_mfnull : ccache_accept;


@@ -789,12 +796,12 @@ tls_retry_connection:
       Avoid using a SIZE option on the MAIL for all random-rcpt checks.
       */
 
       Avoid using a SIZE option on the MAIL for all random-rcpt checks.
       */
 

-      sx.avoid_option = OPTION_SIZE;
+      sx->avoid_option = OPTION_SIZE;

 
       /* Remember when we last did a random test */
       new_domain_record.random_stamp = time(NULL);
 
 
       /* Remember when we last did a random test */
       new_domain_record.random_stamp = time(NULL);
 

-      if (smtp_write_mail_and_rcpt_cmds(&sx, &yield) == 0)
+      if (smtp_write_mail_and_rcpt_cmds(sx, &yield) == 0)

        switch(addr->transport_return)
          {
          case PENDING_OK:      /* random was accepted, unfortunately */
        switch(addr->transport_return)
          {
          case PENDING_OK:      /* random was accepted, unfortunately */


@@ -805,36 +812,36 @@ tls_retry_connection:
            goto no_conn;
          case FAIL:            /* rejected: the preferred result */
            new_domain_record.random_result = ccache_reject;
            goto no_conn;
          case FAIL:            /* rejected: the preferred result */
            new_domain_record.random_result = ccache_reject;

-           sx.avoid_option = 0;
+           sx->avoid_option = 0;

 
            /* Between each check, issue RSET, because some servers accept only
            one recipient after MAIL FROM:<>.
            XXX We don't care about that for postmaster_full.  Should we? */
 
            if ((done =
 
            /* Between each check, issue RSET, because some servers accept only
            one recipient after MAIL FROM:<>.
            XXX We don't care about that for postmaster_full.  Should we? */
 
            if ((done =

-             smtp_write_command(&sx, SCMD_FLUSH, "RSET\r\n") >= 0 &&
-             smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2', callout)))
+             smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0 &&
+             smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', callout)))

              break;
 
            HDEBUG(D_acl|D_v)
              debug_printf_indent("problem after random/rset/mfrom; reopen conn\n");
            random_local_part = NULL;
 #ifndef DISABLE_TLS
              break;
 
            HDEBUG(D_acl|D_v)
              debug_printf_indent("problem after random/rset/mfrom; reopen conn\n");
            random_local_part = NULL;
 #ifndef DISABLE_TLS

-           tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
+           tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);

 #endif
            HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP(close)>>\n");
 #endif
            HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP(close)>>\n");

-           (void)close(sx.cctx.sock);
-           sx.cctx.sock = -1;
+           (void)close(sx->cctx.sock);
+           sx->cctx.sock = -1;

 #ifndef DISABLE_EVENT
            (void) event_raise(addr->transport->event_action,
                              US"tcp:close", NULL);
 #endif
            addr->address = main_address;
            addr->transport_return = PENDING_DEFER;
 #ifndef DISABLE_EVENT
            (void) event_raise(addr->transport->event_action,
                              US"tcp:close", NULL);
 #endif
            addr->address = main_address;
            addr->transport_return = PENDING_DEFER;

-           sx.first_addr = sx.sync_addr = addr;
-           sx.ok = FALSE;
-           sx.send_rset = TRUE;
-           sx.completed_addr = FALSE;
+           sx->first_addr = sx->sync_addr = addr;
+           sx->ok = FALSE;
+           sx->send_rset = TRUE;
+           sx->completed_addr = FALSE;

            goto tls_retry_connection;
          case DEFER:           /* 4xx response to random */
            break;              /* Just to be clear. ccache_unknown, !done. */
            goto tls_retry_connection;
          case DEFER:           /* 4xx response to random */
            break;              /* Just to be clear. ccache_unknown, !done. */


@@ -843,10 +850,10 @@ tls_retry_connection:
       /* Re-setup for main verify, or for the error message when failing */
       addr->address = main_address;
       addr->transport_return = PENDING_DEFER;
       /* Re-setup for main verify, or for the error message when failing */
       addr->address = main_address;
       addr->transport_return = PENDING_DEFER;

-      sx.first_addr = sx.sync_addr = addr;
-      sx.ok = FALSE;
-      sx.send_rset = TRUE;
-      sx.completed_addr = FALSE;
+      sx->first_addr = sx->sync_addr = addr;
+      sx->ok = FALSE;
+      sx->send_rset = TRUE;
+      sx->completed_addr = FALSE;

       }
     else
       done = TRUE;
       }
     else
       done = TRUE;


@@ -857,10 +864,10 @@ tls_retry_connection:
     if (done)
       {
       if (!(options & vopt_is_recipient  &&  options & vopt_callout_no_cache))
     if (done)
       {
       if (!(options & vopt_is_recipient  &&  options & vopt_callout_no_cache))

-       sx.avoid_option = OPTION_SIZE;
+       sx->avoid_option = OPTION_SIZE;

 
       done = FALSE;
 
       done = FALSE;

-      switch(smtp_write_mail_and_rcpt_cmds(&sx, &yield))
+      switch(smtp_write_mail_and_rcpt_cmds(sx, &yield))

        {
        case 0:  switch(addr->transport_return) /* ok so far */
                    {
        {
        case 0:  switch(addr->transport_return) /* ok so far */
                    {


@@ -878,7 +885,7 @@ tls_retry_connection:
 
        case -1:                                /* MAIL response error */
                  *failure_ptr = US"mail";
 
        case -1:                                /* MAIL response error */
                  *failure_ptr = US"mail";

-                 if (errno == 0 && sx.buffer[0] == '5')
+                 if (errno == 0 && sx->buffer[0] == '5')

                    {
                    setflag(addr, af_verify_nsfail);
                    if (from_address[0] == 0)
                    {
                    setflag(addr, af_verify_nsfail);
                    if (from_address[0] == 0)


@@ -908,8 +915,8 @@ tls_retry_connection:
       cancel_cutthrough_connection(TRUE, US"postmaster verify");
       HDEBUG(D_acl|D_v) debug_printf_indent("Cutthrough cancelled by presence of postmaster verify\n");
 
       cancel_cutthrough_connection(TRUE, US"postmaster verify");
       HDEBUG(D_acl|D_v) debug_printf_indent("Cutthrough cancelled by presence of postmaster verify\n");
 

-      done = smtp_write_command(&sx, SCMD_FLUSH, "RSET\r\n") >= 0
-          && smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2', callout);
+      done = smtp_write_command(sx, SCMD_FLUSH, "RSET\r\n") >= 0
+          && smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', callout);

 
       if (done)
        {
 
       if (done)
        {


@@ -919,23 +926,23 @@ tls_retry_connection:
        addr->address = string_sprintf("postmaster@%.1000s", addr->domain);
        addr->transport_return = PENDING_DEFER;
 
        addr->address = string_sprintf("postmaster@%.1000s", addr->domain);
        addr->transport_return = PENDING_DEFER;
 

-       sx.from_addr = pm_mailfrom;
-       sx.first_addr = sx.sync_addr = addr;
-       sx.ok = FALSE;
-       sx.send_rset = TRUE;
-       sx.completed_addr = FALSE;
-       sx.avoid_option = OPTION_SIZE;
+       sx->from_addr = pm_mailfrom;
+       sx->first_addr = sx->sync_addr = addr;
+       sx->ok = FALSE;
+       sx->send_rset = TRUE;
+       sx->completed_addr = FALSE;
+       sx->avoid_option = OPTION_SIZE;

 
 

-       if(  smtp_write_mail_and_rcpt_cmds(&sx, &yield) == 0
+       if(  smtp_write_mail_and_rcpt_cmds(sx, &yield) == 0

          && addr->transport_return == PENDING_OK
          )
          done = TRUE;
        else
          done = (options & vopt_callout_fullpm) != 0
          && addr->transport_return == PENDING_OK
          )
          done = TRUE;
        else
          done = (options & vopt_callout_fullpm) != 0

-             && smtp_write_command(&sx, SCMD_FLUSH,
+             && smtp_write_command(sx, SCMD_FLUSH,

                            "RCPT TO:<postmaster>\r\n") >= 0
                            "RCPT TO:<postmaster>\r\n") >= 0

-             && smtp_read_response(&sx, sx.buffer,
-                           sizeof(sx.buffer), '2', callout);
+             && smtp_read_response(sx, sx->buffer,
+                           sizeof(sx->buffer), '2', callout);

 
        /* Sort out the cache record */
 
 
        /* Sort out the cache record */
 


@@ -943,7 +950,7 @@ tls_retry_connection:
 
        if (done)
          new_domain_record.postmaster_result = ccache_accept;
 
        if (done)
          new_domain_record.postmaster_result = ccache_accept;

-       else if (errno == 0 && sx.buffer[0] == '5')
+       else if (errno == 0 && sx->buffer[0] == '5')

          {
          *failure_ptr = US"postmaster";
          setflag(addr, af_verify_pmfail);
          {
          *failure_ptr = US"postmaster";
          setflag(addr, af_verify_pmfail);


@@ -968,7 +975,7 @@ no_conn:
       {
       case ETIMEDOUT:
        HDEBUG(D_verify) debug_printf("SMTP timeout\n");
       {
       case ETIMEDOUT:
        HDEBUG(D_verify) debug_printf("SMTP timeout\n");

-       sx.send_quit = FALSE;
+       sx->send_quit = FALSE;

        break;
 
 #ifdef SUPPORT_I18N
        break;
 
 #ifdef SUPPORT_I18N


@@ -986,11 +993,11 @@ no_conn:
        break;
 #endif
       case ECONNREFUSED:
        break;
 #endif
       case ECONNREFUSED:

-       sx.send_quit = FALSE;
+       sx->send_quit = FALSE;

        break;
 
       case 0:
        break;
 
       case 0:

-       if (*sx.buffer == 0) Ustrcpy(sx.buffer, US"connection dropped");
+       if (*sx->buffer == 0) Ustrcpy(sx->buffer, US"connection dropped");

 
        /*XXX test here is ugly; seem to have a split of responsibility for
        building this message.  Need to rationalise.  Where is it done
 
        /*XXX test here is ugly; seem to have a split of responsibility for
        building this message.  Need to rationalise.  Where is it done


@@ -999,16 +1006,36 @@ no_conn:
        */
        if (!addr->message) addr->message =
          string_sprintf("response to \"%s\" was: %s",
        */
        if (!addr->message) addr->message =
          string_sprintf("response to \"%s\" was: %s",

-                         big_buffer, string_printing(sx.buffer));
+                         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
        addr->user_message = options & vopt_is_recipient

-         ? string_sprintf("Callout verification failed:\n%s", sx.buffer)
+         ? string_sprintf("Callout verification failed:\n%s", sx->buffer)

          : string_sprintf("Called:   %s\nSent:     %s\nResponse: %s",
          : string_sprintf("Called:   %s\nSent:     %s\nResponse: %s",

-           host->address, big_buffer, sx.buffer);
+           host->address, big_buffer, sx->buffer);

 
        /* Hard rejection ends the process */
 
 
        /* Hard rejection ends the process */
 

-       if (sx.buffer[0] == '5')   /* Address rejected */
+       if (sx->buffer[0] == '5')   /* Address rejected */

          {
          yield = FAIL;
          done = TRUE;
          {
          yield = FAIL;
          done = TRUE;


@@ -1055,7 +1082,7 @@ no_conn:
        && !random_local_part
        && !pm_mailfrom
        && cutthrough.cctx.sock < 0
        && !random_local_part
        && !pm_mailfrom
        && cutthrough.cctx.sock < 0

-       && !sx.lmtp
+       && !sx->lmtp

        )
       {
       HDEBUG(D_acl|D_v) debug_printf_indent("holding verify callout open for %s\n",
        )
       {
       HDEBUG(D_acl|D_v) debug_printf_indent("holding verify callout open for %s\n",


@@ -1065,7 +1092,7 @@ no_conn:
       cutthrough.callout_hold_only = !cutthrough.delivery;
       cutthrough.is_tls =      tls_out.active.sock >= 0;
       /* We assume no buffer in use in the outblock */
       cutthrough.callout_hold_only = !cutthrough.delivery;
       cutthrough.is_tls =      tls_out.active.sock >= 0;
       /* We assume no buffer in use in the outblock */

-      cutthrough.cctx =                sx.cctx;
+      cutthrough.cctx =                sx->cctx;

       cutthrough.nrcpt =       1;
       cutthrough.transport =   addr->transport->name;
       cutthrough.interface =   interface;
       cutthrough.nrcpt =       1;
       cutthrough.transport =   addr->transport->name;
       cutthrough.interface =   interface;


@@ -1101,23 +1128,23 @@ no_conn:
       /* Ensure no cutthrough on multiple verifies that were incompatible */
       if (options & vopt_callout_recipsender)
         cancel_cutthrough_connection(TRUE, US"not usable for cutthrough");
       /* Ensure no cutthrough on multiple verifies that were incompatible */
       if (options & vopt_callout_recipsender)
         cancel_cutthrough_connection(TRUE, US"not usable for cutthrough");

-      if (sx.send_quit)
-       if (smtp_write_command(&sx, SCMD_FLUSH, "QUIT\r\n") != -1)
+      if (sx->send_quit)
+       if (smtp_write_command(sx, SCMD_FLUSH, "QUIT\r\n") != -1)

          /* Wait a short time for response, and discard it */
          /* Wait a short time for response, and discard it */

-         smtp_read_response(&sx, sx.buffer, sizeof(sx.buffer), '2', 1);
+         smtp_read_response(sx, sx->buffer, sizeof(sx->buffer), '2', 1);

 
 

-      if (sx.cctx.sock >= 0)
+      if (sx->cctx.sock >= 0)

        {
 #ifndef DISABLE_TLS
        {
 #ifndef DISABLE_TLS

-       if (sx.cctx.tls_ctx)
+       if (sx->cctx.tls_ctx)

          {
          {

-         tls_close(sx.cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
-         sx.cctx.tls_ctx = NULL;
+         tls_close(sx->cctx.tls_ctx, TLS_SHUTDOWN_NOWAIT);
+         sx->cctx.tls_ctx = NULL;

          }
 #endif
        HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP(close)>>\n");
          }
 #endif
        HDEBUG(D_transport|D_acl|D_v) debug_printf_indent("  SMTP(close)>>\n");

-       (void)close(sx.cctx.sock);
-       sx.cctx.sock = -1;
+       (void)close(sx->cctx.sock);
+       sx->cctx.sock = -1;

 #ifndef DISABLE_EVENT
        (void) event_raise(addr->transport->event_action, US"tcp:close", NULL);
 #endif
 #ifndef DISABLE_EVENT
        (void) event_raise(addr->transport->event_action, US"tcp:close", NULL);
 #endif


@@ -2267,7 +2294,7 @@ for (header_line * h = header_list; h && yield == OK; h = h->next)
         {
         if (!f.allow_unqualified_recipient) recipient = NULL;
         }
         {
         if (!f.allow_unqualified_recipient) recipient = NULL;
         }

-      if (recipient == NULL) errmess = US"unqualified address not permitted";
+      if (!recipient) errmess = US"unqualified address not permitted";

       }
 
     /* It's an error if no address could be extracted, except for the special
       }
 
     /* It's an error if no address could be extracted, except for the special


@@ -2581,7 +2608,7 @@ for (int i = 0; i < 3 && !done; i++)
         /* If we found an empty address, just carry on with the next one, but
         kill the message. */
 
         /* If we found an empty address, just carry on with the next one, but
         kill the message. */
 

-        if (address == NULL && Ustrcmp(*log_msgptr, "empty address") == 0)
+        if (!address && Ustrcmp(*log_msgptr, "empty address") == 0)

           {
           *log_msgptr = NULL;
           s = ss;
           {
           *log_msgptr = NULL;
           s = ss;


@@ -2592,7 +2619,7 @@ for (int i = 0; i < 3 && !done; i++)
         function, and ensure that the failing address gets added to the error
         message. */
 
         function, and ensure that the failing address gets added to the error
         message. */
 

-        if (address == NULL)
+        if (!address)

           {
           new_ok = FAIL;
           while (ss > s && isspace(ss[-1])) ss--;
           {
           new_ok = FAIL;
           while (ss > s && isspace(ss[-1])) ss--;


@@ -3351,7 +3378,7 @@ 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 +3403,7 @@ 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 +3411,7 @@ 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 +3431,7 @@ 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 +3446,58 @@ 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*/

 
 

-    if (!cb->rhs) cb->rc = DNS_NODATA;
+    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. */
+
+      time_t soa_negttl = dns_expire_from_soa(dnsa, T_A);
+      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 +3508,7 @@ 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 +3627,9 @@ 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 +3745,7 @@ 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 +3755,7 @@ 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 +3809,7 @@ 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 +3851,7 @@ 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 +3873,9 @@ 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 +3887,6 @@ 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);