Preserve IPv6 scope_id in edges.

When creating an edge after authenticating a peer, we copy the
address used for the TCP connection, but change the port to that used
for UDP. But the way we did it discarded the scope_id for IPv6
addresses. This prevented UDP communication from working correctly when
connecting to a peer on the same LAN using an IPv6 link-local address.

Thanks to Rafał Leśniak for pointing out this issue.

diff --git a/src/netutl.c b/src/netutl.c
index 2eebb64..a9ad17c 100644 (file)
--- a/src/netutl.c
+++ b/src/netutl.c
@@ -234,3 +234,22 @@ void sockaddrunmap(sockaddr_t *sa) {
                sa->in.sin_family = AF_INET;
        }
 }
+
+void sockaddr_setport(sockaddr_t *sa, const char *port) {
+       uint16_t portnum = htons(atoi(port));
+       if(!portnum)
+               return;
+       switch(sa->sa.sa_family) {
+               case AF_INET:
+                       sa->in.sin_port = portnum;
+                       break;
+               case AF_INET6:
+                       sa->in6.sin6_port = portnum;
+                       break;
+               case AF_UNKNOWN:
+                       free(sa->unknown.port);
+                       sa->unknown.port = xstrdup(port);
+               default:
+                       return;
+       }
+}

diff --git a/src/netutl.h b/src/netutl.h
index 471cae7..2e2f293 100644 (file)
--- a/src/netutl.h
+++ b/src/netutl.h
@@ -34,5 +34,6 @@ extern int sockaddrcmp_noport(const sockaddr_t *, const sockaddr_t *);
 extern void sockaddrunmap(sockaddr_t *);
 extern void sockaddrfree(sockaddr_t *);
 extern void sockaddrcpy(sockaddr_t *, const sockaddr_t *);
+extern void sockaddr_setport(sockaddr_t *, const char *);
 
 #endif /* __TINC_NETUTL_H__ */

diff --git a/src/protocol_auth.c b/src/protocol_auth.c
index 0a7ad1c..65c5e89 100644 (file)
--- a/src/protocol_auth.c
+++ b/src/protocol_auth.c
@@ -790,7 +790,6 @@ bool ack_h(connection_t *c, const char *request) {
                return upgrade_h(c, request);
 
        char hisport[MAX_STRING_SIZE];
-       char *hisaddress;
        int weight, mtu;
        uint32_t options;
        node_t *n;
@@ -867,19 +866,13 @@ bool ack_h(connection_t *c, const char *request) {
        c->edge = new_edge();
        c->edge->from = myself;
        c->edge->to = n;
-       sockaddr2str(&c->address, &hisaddress, NULL);
-       c->edge->address = str2sockaddr(hisaddress, hisport);
-       free(hisaddress);
+       sockaddr_setport(&c->address, hisport);
        sockaddr_t local_sa;
        socklen_t local_salen = sizeof local_sa;
        if (getsockname(c->socket, &local_sa.sa, &local_salen) < 0)
                logger(DEBUG_ALWAYS, LOG_WARNING, "Could not get local socket address for connection with %s", c->name);
-       else {
-               char *local_address;
-               sockaddr2str(&local_sa, &local_address, NULL);
-               c->edge->local_address = str2sockaddr(local_address, myport);
-               free(local_address);
-       }
+       else
+               sockaddr_setport(&local_sa, myport);
        c->edge->weight = (weight + c->estimated_weight) / 2;
        c->edge->connection = c;
        c->edge->options = c->options;