Handle tun prefixing with AF_INET on BSD

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

diff --git a/tun.c b/tun.c
index d804271..c0aa3c2 100644 (file)
--- a/tun.c
+++ b/tun.c
@@ -39,6 +39,10 @@
 
 #include "openconnect.h"
 
+#ifdef BSD
+#define TUN_HAS_AF_PREFIX 1
+#endif
+
 static int local_config_tun(struct openconnect_info *vpninfo, int mtu_only)
 {
        struct ifreq ifr;
@@ -343,13 +347,21 @@ int setup_tun(struct openconnect_info *vpninfo)
 
 int tun_mainloop(struct openconnect_info *vpninfo, int *timeout)
 {
-       char buf[2000];
+       unsigned char buf[2000];
        int len;
        int work_done = 0;
 
        if (FD_ISSET(vpninfo->tun_fd, &vpninfo->select_rfds)) {
                while ((len = read(vpninfo->tun_fd, buf, sizeof(buf))) > 0) {
-                       if (queue_new_packet(&vpninfo->outgoing_queue, AF_INET, buf, len))
+                       unsigned char *pkt = buf;
+#ifdef TUN_HAS_AF_PREFIX
+                       if (*(int *)buf != htonl(AF_INET))
+                               continue;
+                       pkt += 4;
+                       len -= 4;
+#endif
+                       if (queue_new_packet(&vpninfo->outgoing_queue, AF_INET,
+                                            pkt, len))
                                break;
 
                        work_done = 1;
@@ -368,8 +380,18 @@ int tun_mainloop(struct openconnect_info *vpninfo, int *timeout)
           the no-longer-full situation, so let's not bother. */
        while (vpninfo->incoming_queue) {
                struct pkt *this = vpninfo->incoming_queue;
+               unsigned char *data = this->data;
+               int len = this->len;
+
                vpninfo->incoming_queue = this->next;
-               if (write(vpninfo->tun_fd, this->data, this->len) < 0 &&
+
+#ifdef TUN_HAS_AF_PREFIX
+               data -= 4;
+               len += 4;
+               *(int *)data = htonl(AF_INET);
+#endif
+
+               if (write(vpninfo->tun_fd, data, len) < 0 &&
                    errno == ENOTCONN) {
                        vpninfo->quit_reason = "Client connection terminated";
                        return 1;