ndp: harden netlink event socket error handling

[project/odhcpd.git] / src / odhcpd.c

diff --git a/src/odhcpd.c b/src/odhcpd.c
index f259239..22a27a4 100644 (file)
--- a/src/odhcpd.c
+++ b/src/odhcpd.c
@@ -31,6 +31,7 @@
 #include <netpacket/packet.h>
 #include <linux/netlink.h>
 #include <linux/if_addr.h>
+#include <linux/neighbour.h>
 #include <linux/rtnetlink.h>
 
 #include <sys/socket.h>
@@ -94,7 +95,7 @@ int main(int argc, char **argv)
 
        ioctl_sock = socket(AF_INET, SOCK_DGRAM | SOCK_CLOEXEC, 0);
 
-       if (!(rtnl_socket = odhcpd_create_nl_socket(NETLINK_ROUTE, 0))) {
+       if (!(rtnl_socket = odhcpd_create_nl_socket(NETLINK_ROUTE))) {
                syslog(LOG_ERR, "Unable to open nl socket: %s", strerror(errno));
                return 2;
        }
@@ -122,7 +123,7 @@ int main(int argc, char **argv)
        return 0;
 }
 
-struct nl_sock *odhcpd_create_nl_socket(int protocol, int groups)
+struct nl_sock *odhcpd_create_nl_socket(int protocol)
 {
        struct nl_sock *nl_sock;
 
@@ -130,9 +131,6 @@ struct nl_sock *odhcpd_create_nl_socket(int protocol, int groups)
        if (!nl_sock)
                goto err;
 
-       if (groups)
-               nl_join_groups(nl_sock, groups);
-
        if (nl_connect(nl_sock, protocol) < 0)
                goto err;
 
@@ -356,9 +354,9 @@ int odhcpd_get_linklocal_interface_address(int ifindex, struct in6_addr *lladdr)
        return status;
 }
 
-int odhcpd_setup_route(const struct in6_addr *addr, int prefixlen,
+int odhcpd_setup_route(const struct in6_addr *addr, const int prefixlen,
                const struct interface *iface, const struct in6_addr *gw,
-               uint32_t metric, bool add)
+               const uint32_t metric, const bool add)
 {
        struct nl_msg *msg;
        struct rtmsg rtm = {
@@ -395,6 +393,37 @@ int odhcpd_setup_route(const struct in6_addr *addr, int prefixlen,
        return nl_wait_for_ack(rtnl_socket);
 }
 
+int odhcpd_setup_proxy_neigh(const struct in6_addr *addr,
+               const struct interface *iface, const bool add)
+{
+       struct nl_msg *msg;
+       struct ndmsg ndm = {
+               .ndm_family = AF_INET6,
+               .ndm_flags = NTF_PROXY,
+               .ndm_ifindex = iface->ifindex,
+       };
+       int ret = 0, flags = NLM_F_REQUEST;
+
+       if (add)
+               flags |= NLM_F_REPLACE | NLM_F_CREATE;
+
+       msg = nlmsg_alloc_simple(add ? RTM_NEWNEIGH : RTM_DELNEIGH, flags);
+       if (!msg)
+               return -1;
+
+       nlmsg_append(msg, &ndm, sizeof(ndm), 0);
+
+       nla_put(msg, NDA_DST, sizeof(*addr), addr);
+
+       ret = nl_send_auto_complete(rtnl_socket, msg);
+       nlmsg_free(msg);
+
+       if (ret < 0)
+               return ret;
+
+       return nl_wait_for_ack(rtnl_socket);
+}
+
 struct interface* odhcpd_get_interface_by_index(int ifindex)
 {
        struct interface *iface;
@@ -447,7 +476,12 @@ static void odhcpd_receive_packets(struct uloop_fd *u, _unused unsigned int even
                getsockopt(u->fd, SOL_SOCKET, SO_ERROR, &ret, &ret_len);
                u->error = false;
                if (e->handle_error)
-                       e->handle_error(ret);
+                       e->handle_error(e, ret);
+       }
+
+       if (e->recv_msgs) {
+               e->recv_msgs(e);
+               return;
        }
 
        while (true) {