netlink: Remove a newline from p-t-p startup message

[secnet.git] / netlink.c

diff --git a/netlink.c b/netlink.c
index bc707579c60ea3d1fe8474198edc0f1df4e6de13..794bffe7b5c6bf3755e7b9c64817b2816eed8865 100644 (file)
--- a/netlink.c
+++ b/netlink.c
@@ -293,6 +293,7 @@ static bool_t netlink_icmp_may_reply(struct buffer_if *buf)
     struct icmphdr *icmph;
     uint32_t source;
 
+    if (buf->size < (int)sizeof(struct icmphdr)) return False;
     iph=(struct iphdr *)buf->start;
     icmph=(struct icmphdr *)buf->start;
     if (iph->protocol==1) {
@@ -338,6 +339,7 @@ static bool_t netlink_icmp_may_reply(struct buffer_if *buf)
    */
 static uint16_t netlink_icmp_reply_len(struct buffer_if *buf)
 {
+    if (buf->size < (int)sizeof(struct iphdr)) return 0;
     struct iphdr *iph=(struct iphdr *)buf->start;
     uint16_t hlen,plen;
 
@@ -354,11 +356,11 @@ static void netlink_icmp_simple(struct netlink *st, struct buffer_if *buf,
                                struct netlink_client *client,
                                uint8_t type, uint8_t code)
 {
-    struct iphdr *iph=(struct iphdr *)buf->start;
     struct icmphdr *h;
     uint16_t len;
 
     if (netlink_icmp_may_reply(buf)) {
+       struct iphdr *iph=(struct iphdr *)buf->start;
        len=netlink_icmp_reply_len(buf);
        h=netlink_icmp_tmpl(st,ntohl(iph->saddr),len);
        h->type=type; h->code=code;
@@ -389,6 +391,7 @@ static bool_t netlink_check(struct netlink *st, struct buffer_if *buf,
        return False;                                   \
     }while(0)
 
+    if (buf->size < (int)sizeof(struct iphdr)) BAD("len %"PRIu32"",buf->size);
     struct iphdr *iph=(struct iphdr *)buf->start;
     int32_t len;
 
@@ -406,6 +409,28 @@ static bool_t netlink_check(struct netlink *st, struct buffer_if *buf,
 #undef BAD
 }
 
+/* Deliver a packet _to_ client; used after we have decided
+ * what to do with it (and just to check that the client has
+ * actually registered a delivery function with us). */
+static void netlink_client_deliver(struct netlink *st,
+                                  struct netlink_client *client,
+                                  uint32_t source, uint32_t dest,
+                                  struct buffer_if *buf)
+{
+    if (!client->deliver) {
+       string_t s,d;
+       s=ipaddr_to_string(source);
+       d=ipaddr_to_string(dest);
+       Message(M_ERR,"%s: dropping %s->%s, client not registered\n",
+               st->name,s,d);
+       free(s); free(d);
+       BUF_FREE(buf);
+       return;
+    }
+    client->deliver(client->dst, buf);
+    client->outcount++;
+}
+
 /* Deliver a packet. "client" is the _origin_ of the packet, not its
    destination, and is NULL for packets from the host and packets
    generated internally in secnet.  */
@@ -413,6 +438,13 @@ static void netlink_packet_deliver(struct netlink *st,
                                   struct netlink_client *client,
                                   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)");
+       BUF_FREE(buf);
+       return;
+    }
+
     struct iphdr *iph=(struct iphdr *)buf->start;
     uint32_t dest=ntohl(iph->daddr);
     uint32_t source=ntohl(iph->saddr);
@@ -511,9 +543,8 @@ static void netlink_packet_deliver(struct netlink *st,
        } else {
            if (best_quality>0) {
                /* XXX Fragment if required */
-               st->routes[best_match]->deliver(
-                   st->routes[best_match]->dst, buf);
-               st->routes[best_match]->outcount++;
+               netlink_client_deliver(st,st->routes[best_match],
+                                      source,dest,buf);
                BUF_ASSERT_FREE(buf);
            } else {
                /* Generate ICMP destination unreachable */
@@ -530,6 +561,7 @@ static void netlink_packet_forward(struct netlink *st,
                                   struct netlink_client *client,
                                   struct buffer_if *buf)
 {
+    if (buf->size < (int)sizeof(struct iphdr)) return;
     struct iphdr *iph=(struct iphdr *)buf->start;
     
     BUF_ASSERT_USED(buf);
@@ -559,6 +591,12 @@ static void netlink_packet_local(struct netlink *st,
 
     st->localcount++;
 
+    if (buf->size < (int)sizeof(struct icmphdr)) {
+       Message(M_WARNING,"%s: short packet addressed to secnet; "
+               "ignoring it\n",st->name);
+       BUF_FREE(buf);
+       return;
+    }
     h=(struct icmphdr *)buf->start;
 
     if ((ntohs(h->iph.frag_off)&0xbfff)!=0) {
@@ -614,6 +652,7 @@ static void netlink_incoming(struct netlink *st, struct netlink_client *client,
        BUF_FREE(buf);
        return;
     }
+    assert(buf->size >= (int)sizeof(struct icmphdr));
     iph=(struct iphdr *)buf->start;
 
     source=ntohl(iph->saddr);
@@ -660,7 +699,7 @@ static void netlink_incoming(struct netlink *st, struct netlink_client *client,
        if (client) {
            st->deliver_to_host(st->dst,buf);
        } else {
-           st->clients->deliver(st->clients->dst,buf);
+           netlink_client_deliver(st,st->clients,source,dest,buf);
        }
        BUF_ASSERT_FREE(buf);
        return;
@@ -726,7 +765,7 @@ static void netlink_dump_routes(struct netlink *st, bool_t requested)
     if (requested) c=M_WARNING;
     if (st->ptp) {
        net=ipaddr_to_string(st->secnet_address);
-       Message(c,"%s: point-to-point (remote end is %s); routes:\n",
+       Message(c,"%s: point-to-point (remote end is %s); routes: ",
                st->name, net);
        free(net);
        netlink_output_subnets(st,c,st->clients->subnets);