6bed4peer TUN

diff --git a/6bed4peer.c b/6bed4peer.c
index c5c60af..cc88948 100644 (file)
--- a/6bed4peer.c
+++ b/6bed4peer.c
@@ -109,7 +109,11 @@ struct in_addr  v4listen;
 
 
 struct {
+#ifdef PEER_USE_TAP
        struct ethhdr eth;
+#else
+       struct tun_pi tun;
+#endif
        union {
                struct {
                        struct ip6_hdr v6hdr;
@@ -122,7 +126,11 @@ struct {
        } udata;
 } __attribute__((packed)) v4data6;
 
+#ifdef PEER_USE_TAP
 #define v4ether        (v4data6.eth)
+#else
+#define v4tunpi6       (v4data6.tun)
+#endif
 #define v4data         ((uint8_t *) &v4data6.udata)
 #define v4hdr6         (&v4data6.udata.idata.v6hdr)
 #define v4src6         (&v4data6.udata.idata.v6hdr.ip6_src)
@@ -141,7 +149,11 @@ struct {
 
 
 struct {
+#ifdef PEER_USE_TAP
        struct ethhdr eth;
+#else
+       struct tun_pi tun;
+#endif
        union {
                uint8_t data [MTU];
                struct {
@@ -151,7 +163,11 @@ struct {
        } udata;
 }  __attribute__((packed)) v6data6;
 
+#ifdef PEER_USE_TAP
 #define v6ether                (v6data6.eth)
+#else
+#define v6tuncmd       (v6data6.tun)
+#endif
 #define v6data         (v6data6.udata.data)
 #define v6hdr6         (&v6data6.udata.ndata.v6hdr)
 #define v6hops         (v6data6.udata.ndata.v6hdr.ip6_hops)
@@ -165,6 +181,11 @@ struct {
 #define v6icmp6csum    (v6data6.udata.ndata.v6icmp.icmp6_cksum)
 #define v6ndtarget     (&v6data6.udata.ndata.v6icmp.icmp6_data16[2])
 
+#ifdef PEER_USE_TAP
+#define HDR_SIZE        (sizeof(struct ethhdr))
+#else
+#define HDR_SIZE        (sizeof(struct tun_pi))
+#endif
 
 /* Structure for tasks in neighbor discovery queues
  */
@@ -294,7 +315,11 @@ bool setup_tunnel (void) {
        if (!have_tunnel) {
                memset (&ifreq, 0, sizeof (ifreq));
                strncpy (ifreq.ifr_name, INTERFACE_NAME_6BED4, IFNAMSIZ);
+#ifdef PEER_USE_TAP
                ifreq.ifr_flags = IFF_TAP | IFF_NO_PI;
+#else
+               ifreq.ifr_flags = IFF_TUN;
+#endif
                if (ok && (ioctl (v6sox, TUNSETIFF, (void *) &ifreq) == -1)) {
                        syslog (LOG_CRIT, "Failed to set interface name: %s\n", strerror (errno));
                        ok = false;
@@ -523,7 +548,7 @@ void redirect_reply (uint8_t *ngbc_llremote, metric_t ngbc_metric) {
        memcpy (v6src6, &v6listen, 16);
        memcpy (v6dst6, v4src6, 16);
        v6icmp6csum = icmp6_checksum ((uint8_t *) v4hdr6, 8 + 16 + 16);
-       handle_6to4_plain_unicast (sizeof (struct ethhdr) + 40 + 8 + 16 + 16, ngbc_llremote);
+       handle_6to4_plain_unicast (HDR_SIZE + 40 + 8 + 16 + 16, ngbc_llremote);
 } 
 
 
@@ -570,12 +595,15 @@ size_t icmp6_prefix (size_t optidx, uint8_t endlife) {
  * a target IPv6 address to service.
  */
 void advertise_6bed4_public_service (struct ndqueue *info) {
+#ifdef PEER_USE_TAP
+
        if (info) {
                memcpy (v6ether.h_dest, info->source_lladdr, 6);
        } else {
                memcpy (v6ether.h_dest, v6ether.h_source, 6);
        }
        memcpy (v6ether.h_source, SERVER_6BED4_PORT_IPV4_MACSTR, 6);
+#endif
        memcpy (v6data, ipv6_defaultrouter_neighbor_advertisement, 8);
        if (info) {
                memcpy (v6dst6, &info->source, 16);
@@ -594,7 +622,7 @@ void advertise_6bed4_public_service (struct ndqueue *info) {
                memcpy (&v6icmp6data [4], &info->target, 16);
        }
        v6icmp6csum = icmp6_checksum ((uint8_t *) v6hdr6, 32);
-       int sent = write (v6sox, &v6data6, sizeof (struct ethhdr) + sizeof (ipv6_defaultrouter_neighbor_advertisement));
+       int sent = write (v6sox, &v6data6, HDR_SIZE + sizeof (ipv6_defaultrouter_neighbor_advertisement));
        if (info) {
                syslog (LOG_DEBUG, "TODO: Neighbor Discovery failed to contact directly -- standard response provided\n");
        } else {
@@ -796,13 +824,15 @@ syslog (LOG_DEBUG, "Message of %zd bytes from neighbor cache, total is now %zd\n
 void handle_4to6_plain (ssize_t v4datalen, struct sockaddr_in *sin) {
        //
        // Send the unwrapped IPv6 message out over v6sox
+#ifdef PEER_USE_TAP
        v4ether.h_proto = htons (ETH_P_IPV6);
        memcpy (v4ether.h_dest,   v6lladdr, 6);
        v4ether.h_source [0] = ntohs (sin->sin_port) & 0xff;
        v4ether.h_source [1] = ntohs (sin->sin_port) >> 8;
        memcpy (v4ether.h_source + 2, &sin->sin_addr, 4);
+#endif
 syslog (LOG_INFO, "Writing IPv6, result = %zd\n",
-       write (v6sox, &v4data6, sizeof (struct ethhdr) + v4datalen)
+       write (v6sox, &v4data6, HDR_SIZE + v4datalen)
 )
        ;
 }
@@ -1108,7 +1138,7 @@ void handle_6to4_plain_unicast (const ssize_t pktlen, const uint8_t *lladdr) {
        ntohs (v4dest.sin_port),
                sendto (v4sox,
                                v6data,
-                               pktlen - sizeof (struct ethhdr),
+                               pktlen - HDR_SIZE,
                                MSG_DONTWAIT,
                                (struct sockaddr *) &v4dest,
                                sizeof (struct sockaddr_in))
@@ -1153,11 +1183,13 @@ void handle_6to4_nd (ssize_t pktlen) {
                memcpy (v6dst6, v6src6, 16);
                memcpy (v6src6, v6listen_linklocal_complete, 16);
                v6icmp6csum = icmp6_checksum ((uint8_t *) v6hdr6, 4 + writepos);
+#ifdef PEER_USE_TAP
                v6ether.h_proto = htons (ETH_P_IPV6);
                memcpy (v6ether.h_dest, v6ether.h_source, 6);
                memcpy (v6ether.h_source, v6lladdr, 6);
+#endif
                syslog (LOG_INFO, "Replying Router Advertisement to the IPv6 Link, result = %zd\n",
-                       write (v6sox, &v6data6, sizeof (struct ethhdr) + sizeof (struct ip6_hdr) + 4 + writepos)
+                       write (v6sox, &v6data6, HDR_SIZE + sizeof (struct ip6_hdr) + 4 + writepos)
                )
                        ;
                break;
@@ -1191,14 +1223,19 @@ void handle_6to4_nd (ssize_t pktlen) {
                        v6plen = htons (4 + 28);
                        memcpy (v6dst6, v6src6, 16);
                        memcpy (v6src6, &v6listen, 16);
+#ifdef PEER_USE_TAP
                        memcpy (v6ether.h_dest, v6ether.h_source, 6);
                        memcpy (v6ether.h_source, v6lladdr, 6);
+#endif
                        v6icmp6csum = icmp6_checksum ((uint8_t *) v6hdr6, 4 + 28);
 syslog (LOG_DEBUG, "Sending trivial reply to fe80::/64 type query\n");
-                       write (v6sox, &v6data6, sizeof (struct ethhdr) + sizeof (struct ip6_hdr) + 4 + 28);
+                       write (v6sox, &v6data6, HDR_SIZE + sizeof (struct ip6_hdr) + 4 + 28);
                        return;
                } else {
+// TODO
+#ifdef PEER_USE_TAP
                        enqueue ((struct in6_addr *) v6ndtarget, (struct in6_addr *) v6src6, v6ether.h_source);
+#endif
                }
                break;
        case ND_NEIGHBOR_ADVERT:
@@ -1223,7 +1260,6 @@ syslog (LOG_DEBUG, "Sending trivial reply to fe80::/64 type query\n");
        }
 }
 
-
 /*
  * Receive an IPv6 package, check its address and pickup IPv4 address and
  * port, then package it as a tunnel message and forward it to IPv4:port.
@@ -1231,15 +1267,29 @@ syslog (LOG_DEBUG, "Sending trivial reply to fe80::/64 type query\n");
  * locally generated.
  */
 void handle_6to4 (void) {
+#ifndef PEER_USE_TAP
+       static uint8_t lladdr [] =
+       {
+               // UDP port
+               UDP_PORT_6BED4 & 0xff,
+               UDP_PORT_6BED4 >> 8,
+               // IPv4 address
+               SERVER_6BED4_IPV4_INT0,
+               SERVER_6BED4_IPV4_INT1,
+               SERVER_6BED4_IPV4_INT2,
+               SERVER_6BED4_IPV4_INT3
+       };
+#endif
        //
        // Receive the IPv6 package and ensure a consistent size
        size_t rawlen = read (v6sox, &v6data6, sizeof (v6data6));
        if (rawlen == -1) {
                return;         /* failure to read, drop */
        }
-       if (rawlen < sizeof (struct ethhdr) + sizeof (struct ip6_hdr) + 1) {
+       if (rawlen < HDR_SIZE + sizeof (struct ip6_hdr) + 1) {
                return;         /* packet too small, drop */
        }
+#ifdef PEER_USE_TAP
        if (v6ether.h_proto != htons (ETH_P_IPV6)) {
                return;         /* not IPv6, drop */
        }
@@ -1250,6 +1300,7 @@ void handle_6to4 (void) {
                syslog (LOG_DEBUG, "TODO: Self-to-self messaging in IPv6 stack ignored\n");
                return;
        }
+#endif
        /*
         * Distinguish types of traffic:
         * Non-plain, Plain Unicast, Plain Multicast
@@ -1267,7 +1318,12 @@ syslog (LOG_DEBUG, "Forwarding non-plain unicast from IPv6 to 6bed4\n");
                        return;
                }
 syslog (LOG_DEBUG, "Forwarding plain unicast from IPv6 to 6bed4\n");
+#ifdef PEER_USE_TAP
                handle_6to4_plain_unicast (rawlen, v6ether.h_dest);
+#else
+               handle_6to4_plain_unicast (rawlen, lladdr);
+#endif
+
        } else {
                //
                // Plain Multicast
@@ -1731,6 +1787,10 @@ int main (int argc, char *argv []) {
        memcpy (&v4listen, &v4peer.sin_addr, 4);
        memset (&v4bind, 0, sizeof (v4bind));
        v4bind.sin_family = AF_INET;
+#ifndef PEER_USE_TAP
+       v4tunpi6.flags = 0;
+       v4tunpi6.proto = htons (ETH_P_IPV6);
+#endif
        //
        // Parse commandline arguments
        if (!process_args (argc, argv)) {