chiark / gitweb /
netlink: Move local_address into struct netlink
[secnet.git] / netlink.c
index 2c3d12d4302b00aea1a59d44dbdd3ca130a532fc..954dbb66f6385e8b65fcd0e9948d521442f0a4cd 100644 (file)
--- a/netlink.c
+++ b/netlink.c
@@ -237,6 +237,11 @@ struct icmphdr {
 
 static const union icmpinfofield icmp_noinfo;
     
+static const char *sender_name(struct netlink_client *sender /* or NULL */)
+{
+    return sender?sender->name:"(local)";
+}
+
 static void netlink_packet_deliver(struct netlink *st,
                                   struct netlink_client *client,
                                   struct buffer_if *buf);
@@ -376,7 +381,9 @@ static uint16_t netlink_icmp_reply_len(struct buffer_if *buf)
 
 /* client indicates where the packet we're constructing a response to
    comes from. NULL indicates the host. */
-static void netlink_icmp_simple(struct netlink *st, struct buffer_if *buf,
+static void netlink_icmp_simple(struct netlink *st,
+                               struct netlink_client *origsender,
+                               struct buffer_if *buf,
                                uint8_t type, uint8_t code,
                                union icmpinfofield info)
 {
@@ -465,6 +472,7 @@ static const char *fragment_filter_header(uint8_t *base, long *hlp)
 
 /* Fragment or send ICMP Fragmentation Needed */
 static void netlink_maybe_fragment(struct netlink *st,
+                                  struct netlink_client *sender,
                                   netlink_deliver_fn *deliver,
                                   void *deliver_dst,
                                   const char *delivery_name,
@@ -496,7 +504,7 @@ static void netlink_maybe_fragment(struct netlink *st,
     if (orig_frag&IPHDR_FRAG_DONT) {
        union icmpinfofield info =
            { .fragneeded = { .unused = 0, .mtu = htons(mtu) } };
-       netlink_icmp_simple(st,buf,
+       netlink_icmp_simple(st,sender,buf,
                            ICMP_TYPE_UNREACHABLE,
                            ICMP_CODE_FRAGMENTATION_REQUIRED,
                            info);
@@ -591,7 +599,7 @@ static void netlink_client_deliver(struct netlink *st,
        BUF_FREE(buf);
        return;
     }
-    netlink_maybe_fragment(st, client->deliver,client->dst,client->name,
+    netlink_maybe_fragment(st,NULL, client->deliver,client->dst,client->name,
                           client->mtu, source,dest,buf);
     client->outcount++;
 }
@@ -599,24 +607,24 @@ static void netlink_client_deliver(struct netlink *st,
 /* Deliver a packet to the host; used after we have decided that that
  * is what to do with it. */
 static void netlink_host_deliver(struct netlink *st,
+                                struct netlink_client *sender,
                                 uint32_t source, uint32_t dest,
                                 struct buffer_if *buf)
 {
-    netlink_maybe_fragment(st, st->deliver_to_host,st->dst,"(host)",
+    netlink_maybe_fragment(st,sender, st->deliver_to_host,st->dst,"(host)",
                           st->mtu, source,dest,buf);
     st->outcount++;
 }
 
-/* Deliver a packet. "client" is the _origin_ of the packet, not its
-   destination, and is NULL for packets from the host and packets
+/* Deliver a packet. "sender"==NULL for packets from the host and packets
    generated internally in secnet.  */
 static void netlink_packet_deliver(struct netlink *st,
-                                  struct netlink_client *client,
+                                  struct netlink_client *sender,
                                   struct buffer_if *buf)
 {
     if (buf->size < (int)sizeof(struct iphdr)) {
        Message(M_ERR,"%s: trying to deliver a too-short packet"
-               " from %s!\n",st->name, client?client->name:"(local)");
+               " from %s!\n",st->name, sender_name(sender));
        BUF_FREE(buf);
        return;
     }
@@ -638,9 +646,9 @@ static void netlink_packet_deliver(struct netlink *st,
        return;
     }
     
-    /* Packets from the host (client==NULL) may always be routed.  Packets
+    /* Packets from the host (sender==NULL) may always be routed.  Packets
        from clients with the allow_route option will also be routed. */
-    if (!client || (client && (client->options & OPT_ALLOWROUTE)))
+    if (!sender || (sender && (sender->options & OPT_ALLOWROUTE)))
        allow_route=True;
 
     /* If !allow_route, we check the routing table anyway, and if
@@ -686,7 +694,7 @@ static void netlink_packet_deliver(struct netlink *st,
        /* The packet's not going down a tunnel.  It might (ought to)
           be for the host.   */
        if (ipset_contains_addr(st->networks,dest)) {
-           netlink_host_deliver(st,source,dest,buf);
+           netlink_host_deliver(st,sender,source,dest,buf);
            BUF_ASSERT_FREE(buf);
        } else {
            string_t s,d;
@@ -695,7 +703,7 @@ static void netlink_packet_deliver(struct netlink *st,
            Message(M_DEBUG,"%s: don't know where to deliver packet "
                    "(s=%s, d=%s)\n", st->name, s, d);
            free(s); free(d);
-           netlink_icmp_simple(st,buf,ICMP_TYPE_UNREACHABLE,
+           netlink_icmp_simple(st,sender,buf,ICMP_TYPE_UNREACHABLE,
                                ICMP_CODE_NET_UNREACHABLE, icmp_noinfo);
            BUF_FREE(buf);
        }
@@ -712,7 +720,7 @@ static void netlink_packet_deliver(struct netlink *st,
                    st->name,s,d);
            free(s); free(d);
                    
-           netlink_icmp_simple(st,buf,ICMP_TYPE_UNREACHABLE,
+           netlink_icmp_simple(st,sender,buf,ICMP_TYPE_UNREACHABLE,
                                ICMP_CODE_NET_PROHIBITED, icmp_noinfo);
            BUF_FREE(buf);
        } else {
@@ -722,7 +730,7 @@ static void netlink_packet_deliver(struct netlink *st,
                BUF_ASSERT_FREE(buf);
            } else {
                /* Generate ICMP destination unreachable */
-               netlink_icmp_simple(st,buf,
+               netlink_icmp_simple(st,sender,buf,
                                    ICMP_TYPE_UNREACHABLE,
                                    ICMP_CODE_NET_UNREACHABLE,
                                    icmp_noinfo);
@@ -734,7 +742,7 @@ static void netlink_packet_deliver(struct netlink *st,
 }
 
 static void netlink_packet_forward(struct netlink *st, 
-                                  struct netlink_client *client,
+                                  struct netlink_client *sender,
                                   struct buffer_if *buf)
 {
     if (buf->size < (int)sizeof(struct iphdr)) return;
@@ -745,7 +753,7 @@ static void netlink_packet_forward(struct netlink *st,
     /* Packet has already been checked */
     if (iph->ttl<=1) {
        /* Generate ICMP time exceeded */
-       netlink_icmp_simple(st,buf,ICMP_TYPE_TIME_EXCEEDED,
+       netlink_icmp_simple(st,sender,buf,ICMP_TYPE_TIME_EXCEEDED,
                            ICMP_CODE_TTL_EXCEEDED,icmp_noinfo);
        BUF_FREE(buf);
        return;
@@ -754,13 +762,13 @@ static void netlink_packet_forward(struct netlink *st,
     iph->check=0;
     iph->check=ip_fast_csum((uint8_t *)iph,iph->ihl);
 
-    netlink_packet_deliver(st,client,buf);
+    netlink_packet_deliver(st,sender,buf);
     BUF_ASSERT_FREE(buf);
 }
 
 /* Deal with packets addressed explicitly to us */
 static void netlink_packet_local(struct netlink *st,
-                                struct netlink_client *client,
+                                struct netlink_client *sender,
                                 struct buffer_if *buf)
 {
     struct icmphdr *h;
@@ -803,7 +811,7 @@ static void netlink_packet_local(struct netlink *st,
        Message(M_WARNING,"%s: unknown incoming ICMP\n",st->name);
     } else {
        /* Send ICMP protocol unreachable */
-       netlink_icmp_simple(st,buf,ICMP_TYPE_UNREACHABLE,
+       netlink_icmp_simple(st,sender,buf,ICMP_TYPE_UNREACHABLE,
                            ICMP_CODE_PROTOCOL_UNREACHABLE,icmp_noinfo);
        BUF_FREE(buf);
        return;
@@ -814,13 +822,13 @@ static void netlink_packet_local(struct netlink *st,
 
 /* If cid==NULL packet is from host, otherwise cid specifies which tunnel 
    it came from. */
-static void netlink_incoming(struct netlink *st, struct netlink_client *client,
+static void netlink_incoming(struct netlink *st, struct netlink_client *sender,
                             struct buffer_if *buf)
 {
     uint32_t source,dest;
     struct iphdr *iph;
     char errmsgbuf[50];
-    const char *sourcedesc=client?client->name:"host";
+    const char *sourcedesc=sender?sender->name:"host";
 
     BUF_ASSERT_USED(buf);
 
@@ -831,7 +839,7 @@ static void netlink_incoming(struct netlink *st, struct netlink_client *client,
        BUF_FREE(buf);
        return;
     }
-    assert(buf->size >= (int)sizeof(struct icmphdr));
+    assert(buf->size >= (int)sizeof(struct iphdr));
     iph=(struct iphdr *)buf->start;
 
     source=ntohl(iph->saddr);
@@ -840,15 +848,15 @@ static void netlink_incoming(struct netlink *st, struct netlink_client *client,
     /* Check source. If we don't like the source, there's no point
        generating ICMP because we won't know how to get it to the
        source of the packet. */
-    if (client) {
+    if (sender) {
        /* Check that the packet source is appropriate for the tunnel
           it came down */
-       if (!ipset_contains_addr(client->networks,source)) {
+       if (!ipset_contains_addr(sender->networks,source)) {
            string_t s,d;
            s=ipaddr_to_string(source);
            d=ipaddr_to_string(dest);
            Message(M_WARNING,"%s: packet from tunnel %s with bad "
-                   "source address (s=%s,d=%s)\n",st->name,client->name,s,d);
+                   "source address (s=%s,d=%s)\n",st->name,sender->name,s,d);
            free(s); free(d);
            BUF_FREE(buf);
            return;
@@ -875,8 +883,8 @@ static void netlink_incoming(struct netlink *st, struct netlink_client *client,
        where it came from.  It's up to external software to check
        address validity and generate ICMP, etc. */
     if (st->ptp) {
-       if (client) {
-           netlink_host_deliver(st,source,dest,buf);
+       if (sender) {
+           netlink_host_deliver(st,sender,source,dest,buf);
        } else {
            netlink_client_deliver(st,st->clients,source,dest,buf);
        }
@@ -887,11 +895,11 @@ static void netlink_incoming(struct netlink *st, struct netlink_client *client,
     /* st->secnet_address needs checking before matching destination
        addresses */
     if (dest==st->secnet_address) {
-       netlink_packet_local(st,client,buf);
+       netlink_packet_local(st,sender,buf);
        BUF_ASSERT_FREE(buf);
        return;
     }
-    netlink_packet_forward(st,client,buf);
+    netlink_packet_forward(st,sender,buf);
     BUF_ASSERT_FREE(buf);
 }
 
@@ -1028,12 +1036,16 @@ static void netlink_inst_set_mtu(void *sst, int32_t new_mtu)
 }
 
 static void netlink_inst_reg(void *sst, netlink_deliver_fn *deliver, 
-                            void *dst)
+                            void *dst, uint32_t *localmtu_r)
 {
     struct netlink_client *c=sst;
+    struct netlink *st=c->nst;
 
     c->deliver=deliver;
     c->dst=dst;
+
+    if (localmtu_r)
+       *localmtu_r=st->mtu;
 }
 
 static struct flagstr netlink_option_table[]={
@@ -1186,6 +1198,8 @@ netlink_deliver_fn *netlink_init(struct netlink *st,
        st->remote_networks=ipset_complement(empty);
        ipset_free(empty);
     }
+    st->local_address=string_item_to_ipaddr(
+       dict_find_item(dict,"local-address", True, "netlink", loc),"netlink");
 
     sa=dict_find_item(dict,"secnet-address",False,"netlink",loc);
     ptpa=dict_find_item(dict,"ptp-address",False,"netlink",loc);