From 12c53f98e44598b87d3f2308e0d892f49d7af8e4 Mon Sep 17 00:00:00 2001

From: Roger Wolff <R.E.Wolff@BitWizard.nl>

Date: Tue, 16 Jul 2013 13:59:52 +0200

Subject: [PATCH] Fix bombout with ipv6 enabled binary on ipv4 only system.

---

 dns.c    | 33 +++++++++++++++++++++------------

 gtk.c    |  6 ++++--

 select.c |  8 ++++++--

 3 files changed, 31 insertions(+), 16 deletions(-)

diff --git a/dns.c b/dns.c

index 371934f..221665d 100644

--- a/dns.c

+++ b/dns.c

@@ -529,10 +529,12 @@ void dns_open(void)

 #ifdef ENABLE_IPV6

   resfd6 = socket(AF_INET6, SOCK_DGRAM, 0);

   if (resfd6 == -1) {

+    // consider making removing this warning. For now leave it in to see 

+    // new code activated. -- REW

     fprintf(stderr,

             "Unable to allocate IPv6 socket for nameserver communication: %s\n",

 	    strerror(errno));

-    exit(-1);

+    //    exit(-1);

   }

 #endif

   option = 1;

@@ -543,11 +545,13 @@ void dns_open(void)

     exit(-1);

   }

 #ifdef ENABLE_IPV6

-  if (setsockopt(resfd6,SOL_SOCKET,SO_BROADCAST,(char *)&option,sizeof(option))) {

-    fprintf(stderr,

-            "Unable to setsockopt() on IPv6 nameserver communication socket: %s\n",

-	    strerror(errno));

-    exit(-1);

+  if (resfd6 > 0) {

+    if (setsockopt(resfd6,SOL_SOCKET,SO_BROADCAST,(char *)&option,sizeof(option))) {

+      fprintf(stderr,

+	      "Unable to setsockopt() on IPv6 nameserver communication socket: %s\n",

+	      strerror(errno));

+      exit(-1);

+    }

   }

 #endif

   longipstr( "127.0.0.1", &localhost, AF_INET );

@@ -933,12 +937,14 @@ void dorequest(char *s,int type,word id)

   hp = (packetheader *)buf;

   hp->id = id;	/* htons() deliberately left out (redundant) */

 #ifdef ENABLE_IPV6

-  for (i = 0;i < NSCOUNT6;i++) {

-    if (!NSSOCKADDR6(i))

-      continue;

-    if (NSSOCKADDR6(i)->sin6_family == AF_INET6)

-      (void)sendto(resfd6,buf,r,0,(struct sockaddr *) NSSOCKADDR6(i),

-		   sizeof(struct sockaddr_in6));

+  if (resfd6 > 0) {

+    for (i = 0;i < NSCOUNT6;i++) {

+      if (!NSSOCKADDR6(i))

+	continue;

+      if (NSSOCKADDR6(i)->sin6_family == AF_INET6)

+	(void)sendto(resfd6,buf,r,0,(struct sockaddr *) NSSOCKADDR6(i),

+		     sizeof(struct sockaddr_in6));

+    }

   }

 #endif

   for (i = 0;i < myres.nscount;i++)

@@ -1327,6 +1333,9 @@ void dns_ack6(void)

   int r,i;

   static char addrstr[INET6_ADDRSTRLEN];

+  // Probably not necessary. -- REW

+  if (resfd6 < 0) return; 

+

   r = recvfrom(resfd6,(byte *)resrecvbuf,MaxPacketsize,0,

                from, &fromlen);

   if (r > 0) {

diff --git a/gtk.c b/gtk.c

index d00f769..38ed507 100644

--- a/gtk.c

+++ b/gtk.c

@@ -615,8 +615,10 @@ void gtk_loop(void)

   net_iochannel = g_io_channel_unix_new(net_waitfd());

   g_io_add_watch(net_iochannel, G_IO_IN, gtk_net_data, NULL);

 #ifdef ENABLE_IPV6

-  dns_iochannel = g_io_channel_unix_new(dns_waitfd6());

-  g_io_add_watch(dns_iochannel, G_IO_IN, gtk_dns_data6, NULL);

+  if (dns_waitfd6() > 0) {

+    dns_iochannel = g_io_channel_unix_new(dns_waitfd6());

+    g_io_add_watch(dns_iochannel, G_IO_IN, gtk_dns_data6, NULL);

+  }

 #endif

   dns_iochannel = g_io_channel_unix_new(dns_waitfd());

   g_io_add_watch(dns_iochannel, G_IO_IN, gtk_dns_data, NULL);

diff --git a/select.c b/select.c

index 0545d9f..e7c397e 100644

--- a/select.c

+++ b/select.c

@@ -80,8 +80,12 @@ void select_loop(void) {

 #ifdef ENABLE_IPV6

     if (dns) {

       dnsfd6 = dns_waitfd6();

-      FD_SET(dnsfd6, &readfd);

-      if(dnsfd6 >= maxfd) maxfd = dnsfd6 + 1;

+      if (dnsfd6 >= 0) {

+        FD_SET(dnsfd6, &readfd);

+        if(dnsfd6 >= maxfd) maxfd = dnsfd6 + 1;

+      } else {

+        dnsfd6 = 0;

+      }

     } else

       dnsfd6 = 0;

 #endif

-- 

1.8.3.1