--- a/mod_gss.c.in

+++ b/mod_gss.c.in

@@ -1412,6 +1412,87 @@ MODRET gss_auth(cmd_rec *cmd) {

     return HANDLED(cmd);

 }

+#ifdef USE_IPV6 /* { */

+#define IPV6_STR_SIZE   128

+

+static int ip6_to_str(struct in6_addr* addr, char* buf, int size) {

+

+    const char *err;

+

+    if(size<IPV6_STR_SIZE)

+        return 0;

+

+    memset(buf, 0, size);

+    err=inet_ntop(AF_INET6, addr, buf, size-1);

+    if(err!=buf)

+        return 0;

+

+    return 1;

+}

+

+static int ip6_to_ip4(struct in6_addr *ip6, struct in_addr *ip4) {

+

+    char buf[IPV6_STR_SIZE];

+

+    if (!ip6_to_str(ip6, buf, IPV6_STR_SIZE))

+        return 0;

+

+    const char *ip4_str=strrchr(buf, ':');

+    if (ip4_str == 0)

+        return 0;

+

+    ip4_str++;

+    if (!inet_aton(ip4_str, ip4))

+        return 0;

+

+    return 1;

+}

+

+static int set_chan_v4mapped(

+    gss_channel_bindings_t chan, struct in_addr *ia, struct in_addr *aa) {

+

+    if (!ip6_to_ip4(&(session.c->remote_addr->na_addr.v6.sin6_addr), ia))

+        return 0;

+

+    if (!ip6_to_ip4(&(session.c->local_addr->na_addr.v6.sin6_addr), aa))

+        return 0;

+

+    chan->initiator_addrtype = GSS_C_AF_INET;

+    chan->initiator_address.length = sizeof(struct in_addr);

+    chan->initiator_address.value = ia;

+

+    chan->acceptor_addrtype = GSS_C_AF_INET;

+    chan->acceptor_address.length = sizeof(struct in_addr);

+    chan->acceptor_address.value = aa;

+

+    chan->application_data.length = 0;

+    chan->application_data.value = 0;

+

+    return 1;

+}

+

+static int try_v4mapped() {

+

+    struct in6_addr* addr;

+

+    if (pr_netaddr_get_family(session.c->remote_addr) != AF_INET6)

+        return 0;

+

+    if (pr_netaddr_get_family(session.c->local_addr) != AF_INET6)

+        return 0;

+

+    addr = (struct in6_addr*)pr_netaddr_get_inaddr(session.c->remote_addr);

+    if (!IN6_IS_ADDR_V4MAPPED(addr))

+        return 0;

+

+    addr = (struct in6_addr*)pr_netaddr_get_inaddr(session.c->local_addr);

+    if (!IN6_IS_ADDR_V4MAPPED(addr))

+        return 0;

+

+    return 1;

+}

+#endif /* } */

+

 /*

    AUTHENTICATION/SECURITY DATA (ADAT)

@@ -1527,6 +1608,12 @@ MODRET gss_adat(cmd_rec *cmd) {

     char *gbuf ;

     gss_channel_bindings_t chan=GSS_C_NO_CHANNEL_BINDINGS;

+    gss_channel_bindings_t chan_sl=GSS_C_NO_CHANNEL_BINDINGS;

+#ifdef USE_IPV6

+    gss_channel_bindings_t chan_v4m=GSS_C_NO_CHANNEL_BINDINGS;

+    struct in_addr ia;

+    struct in_addr aa;

+#endif

     if (!gss_engine)

         return DECLINED(cmd);

@@ -1631,13 +1718,22 @@ MODRET gss_adat(cmd_rec *cmd) {

 	    continue;

 	}

+        chan_sl = chan;

+#ifdef USE_IPV6

+        if (try_v4mapped()) {

+            chan_v4m = pcalloc(cmd->tmp_pool,sizeof(*chan_v4m));

+            if (set_chan_v4mapped(chan_v4m, &ia, &aa))

+                chan_sl = chan_v4m;

+        }

+#endif

+

 	found++;

 	gcontext = GSS_C_NO_CONTEXT;

 	accept_maj = gss_accept_sec_context(&accept_min,

 	   				    &gcontext, /* context_handle */

 					    server_creds, /* verifier_cred_handle */

 					    &tok, /* input_token */

-					    chan, /* channel bindings */

+					    chan_sl, /* channel bindings */

 					    &client, /* src_name */

 					    &mechid, /* mech_type */

 					    &out_tok, /* output_token */