dns: listen on ipv6

dns.c

@@ -18,18 +18,18 @@
 
 #if defined IP_RECVDSTADDR
 # define DSTADDR_SOCKOPT IP_RECVDSTADDR
-# define DSTADDR_DATASIZE (CMSG_SPACE(sizeof(struct in_addr)))
+# define DSTADDR_DATASIZE (CMSG_SPACE(sizeof(struct in6_addr)))
 # define dstaddr(x) (CMSG_DATA(x))
-#elif defined IP_PKTINFO
-struct in_pktinfo {
-  unsigned int   ipi_ifindex;  /* Interface index */
-  struct in_addr ipi_spec_dst; /* Local address */
-  struct in_addr ipi_addr;     /* Header Destination address */
-};
+#elif defined IPV6_PKTINFO
+struct in6_pktinfo
+  {
+    struct in6_addr ipi6_addr;	/* src/dst IPv6 address */
+    unsigned int ipi6_ifindex;	/* send/recv interface index */
+  };
 
-# define DSTADDR_SOCKOPT IP_PKTINFO
-# define DSTADDR_DATASIZE (CMSG_SPACE(sizeof(struct in_pktinfo)))
-# define dstaddr(x) (&(((struct in_pktinfo *)(CMSG_DATA(x)))->ipi_addr))
+# define DSTADDR_SOCKOPT IPV6_PKTINFO
+# define DSTADDR_DATASIZE (CMSG_SPACE(sizeof(struct in6_pktinfo)))
+# define dstaddr(x) (&(((struct in6_pktinfo *)(CMSG_DATA(x)))->ipi6_addr))
 #else
 # error "can't determine socket option"
 #endif
@@ -366,31 +366,31 @@ ssize_t static dnshandle(dns_opt_t *opt, const unsigned char *inbuf, size_t insi
 static int listenSocket = -1;
 
 int dnsserver(dns_opt_t *opt) {
-  struct sockaddr_in si_other;
+  struct sockaddr_in6 si_other;
   int senderSocket = -1;
-  senderSocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+  senderSocket = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
   if (senderSocket == -1) 
     return -3;
 
   int replySocket;
   if (listenSocket == -1) {
-    struct sockaddr_in si_me;
-    if ((listenSocket=socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP))==-1) {
+    struct sockaddr_in6 si_me;
+    if ((listenSocket=socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP))==-1) {
       listenSocket = -1;
       return -1;
     }
-    replySocket = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+    replySocket = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
     if (replySocket == -1)
     {
       close(listenSocket);
       return -1;
     }
     int sockopt = 1;
-    setsockopt(listenSocket, IPPROTO_IP, DSTADDR_SOCKOPT, &sockopt, sizeof sockopt);
+    setsockopt(listenSocket, IPPROTO_IPV6, DSTADDR_SOCKOPT, &sockopt, sizeof sockopt);
     memset((char *) &si_me, 0, sizeof(si_me));
-    si_me.sin_family = AF_INET;
-    si_me.sin_port = htons(opt->port);
-    si_me.sin_addr.s_addr = INADDR_ANY;
+    si_me.sin6_family = AF_INET6;
+    si_me.sin6_port = htons(opt->port);
+    si_me.sin6_addr = in6addr_any;
     if (bind(listenSocket, (struct sockaddr*)&si_me, sizeof(si_me))==-1)
       return -2;
   }
@@ -414,7 +414,7 @@ int dnsserver(dns_opt_t *opt) {
   for (; 1; ++(opt->nRequests))
   {
     ssize_t insize = recvmsg(listenSocket, &msg, 0);
-    unsigned char *addr = (unsigned char*)&si_other.sin_addr.s_addr;
+//    unsigned char *addr = (unsigned char*)&si_other.sin_addr.s_addr;
 //    printf("DNS: Request %llu from %i.%i.%i.%i:%i of %i bytes\n", (unsigned long long)(opt->nRequests), addr[0], addr[1], addr[2], addr[3], ntohs(si_other.sin_port), (int)insize);
     if (insize <= 0)
       continue;