Make routset()/route6set() use netlink.

Signed-off-by: Benjamin Cama <benoar@dolka.fr>

diff --git a/l2tpns.c b/l2tpns.c
index f530955..110029a 100644 (file)
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -200,6 +200,8 @@ struct Tstats *_statistics = NULL;
 struct Tringbuffer *ringbuffer = NULL;
 #endif
 
+static ssize_t netlink_send(struct nlmsghdr *nh);
+static void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen);
 static void cache_ipmap(in_addr_t ip, sessionidt s);
 static void uncache_ipmap(in_addr_t ip);
 static void cache_ipv6map(struct in6_addr ip, int prefixlen, sessionidt s);
@@ -423,36 +425,51 @@ void random_data(uint8_t *buf, int len)
 //
 static void routeset(sessionidt s, in_addr_t ip, int prefixlen, in_addr_t gw, int add)
 {
-       struct rtentry r;
-       in_addr_t mask;
+       struct {
+               struct nlmsghdr nh;
+               struct rtmsg rt;
+               char buf[32];
+       } req;
        int i;
+       in_addr_t n_ip;
 
        if (!prefixlen) prefixlen = 32;
 
-       mask = 0xffffffff << (32 - prefixlen);
+       ip &= 0xffffffff << (32 - prefixlen);;  // Force the ip to be the first one in the route.
 
-       ip &= mask;     // Force the ip to be the first one in the route.
+       memset(&req, 0, sizeof(req));
 
-       memset(&r, 0, sizeof(r));
-       r.rt_dev = config->tundevice;
-       r.rt_dst.sa_family = AF_INET;
-       *(uint32_t *) & (((struct sockaddr_in *) &r.rt_dst)->sin_addr.s_addr) = htonl(ip);
-       r.rt_gateway.sa_family = AF_INET;
-       *(uint32_t *) & (((struct sockaddr_in *) &r.rt_gateway)->sin_addr.s_addr) = htonl(gw);
-       r.rt_genmask.sa_family = AF_INET;
-       *(uint32_t *) & (((struct sockaddr_in *) &r.rt_genmask)->sin_addr.s_addr) = htonl(mask);
-       r.rt_flags = (RTF_UP | RTF_STATIC);
+       if (add)
+       {
+               req.nh.nlmsg_type = RTM_NEWROUTE;
+               req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE;
+       }
+       else
+               req.nh.nlmsg_type = RTM_DELROUTE;
+       req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt));
+
+       req.rt.rtm_family = AF_INET;
+       req.rt.rtm_dst_len = prefixlen;
+       req.rt.rtm_table = RT_TABLE_MAIN;
+       req.rt.rtm_protocol = RTPROT_BOOT; // XXX
+       req.rt.rtm_scope = RT_SCOPE_LINK;
+       req.rt.rtm_type = RTN_UNICAST;
+
+       netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int));
+       n_ip = htonl(ip);
+       netlink_addattr(&req.nh, RTA_DST, &n_ip, sizeof(n_ip));
        if (gw)
-               r.rt_flags |= RTF_GATEWAY;
-       else if (prefixlen == 32)
-               r.rt_flags |= RTF_HOST;
+       {
+               n_ip = htonl(gw);
+               netlink_addattr(&req.nh, RTA_GATEWAY, &n_ip, sizeof(n_ip));
+       }
 
        LOG(1, s, 0, "Route %s %s/%d%s%s\n", add ? "add" : "del",
            fmtaddr(htonl(ip), 0), prefixlen,
            gw ? " via" : "", gw ? fmtaddr(htonl(gw), 2) : "");
 
-       if (ioctl(ifrfd, add ? SIOCADDRT : SIOCDELRT, (void *) &r) < 0)
-               LOG(0, 0, 0, "routeset() error in ioctl: %s\n", strerror(errno));
+       if (netlink_send(&req.nh) < 0)
+               LOG(0, 0, 0, "routeset() error in sending netlink message: %s\n", strerror(errno));
 
 #ifdef BGP
        if (add)
@@ -481,31 +498,50 @@ static void routeset(sessionidt s, in_addr_t ip, int prefixlen, in_addr_t gw, in
 
 void route6set(sessionidt s, struct in6_addr ip, int prefixlen, int add)
 {
-       struct in6_rtmsg rt;
+       struct {
+               struct nlmsghdr nh;
+               struct rtmsg rt;
+               char buf[64];
+       } req;
+       int metric;
        char ipv6addr[INET6_ADDRSTRLEN];
 
-       if (ifr6fd < 0)
+       if (!config->ipv6_prefix.s6_addr[0])
        {
                LOG(0, 0, 0, "Asked to set IPv6 route, but IPv6 not setup.\n");
                return;
        }
 
-       memset(&rt, 0, sizeof(rt));
+       memset(&req, 0, sizeof(req));
+
+       if (add)
+       {
+               req.nh.nlmsg_type = RTM_NEWROUTE;
+               req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE;
+       }
+       else
+               req.nh.nlmsg_type = RTM_DELROUTE;
+       req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt));
+
+       req.rt.rtm_family = AF_INET6;
+       req.rt.rtm_dst_len = prefixlen;
+       req.rt.rtm_table = RT_TABLE_MAIN;
+       req.rt.rtm_protocol = RTPROT_BOOT; // XXX
+       req.rt.rtm_scope = RT_SCOPE_LINK;
+       req.rt.rtm_type = RTN_UNICAST;
 
-       memcpy(&rt.rtmsg_dst, &ip, sizeof(struct in6_addr));
-       rt.rtmsg_dst_len = prefixlen;
-       rt.rtmsg_metric = 1;
-       rt.rtmsg_flags = RTF_UP;
-       rt.rtmsg_ifindex = tunidx;
+       netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int));
+       netlink_addattr(&req.nh, RTA_DST, &ip, sizeof(ip));
+       metric = 1;
+       netlink_addattr(&req.nh, RTA_METRICS, &metric, sizeof(metric));
 
        LOG(1, 0, 0, "Route %s %s/%d\n",
            add ? "add" : "del",
            inet_ntop(AF_INET6, &ip, ipv6addr, INET6_ADDRSTRLEN),
            prefixlen);
 
-       if (ioctl(ifr6fd, add ? SIOCADDRT : SIOCDELRT, (void *) &rt) < 0)
-               LOG(0, 0, 0, "route6set() error in ioctl: %s\n",
-                               strerror(errno));
+       if (netlink_send(&req.nh) < 0)
+               LOG(0, 0, 0, "route6set() error in sending netlink message: %s\n", strerror(errno));
 
        // FIXME: need to add BGP routing (RFC2858)
 
@@ -580,7 +616,7 @@ static ssize_t netlink_recv(void *buf, ssize_t len)
 }
 
 /* adapted from iproute2 */
-void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen)
+static void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen)
 {
        int len = RTA_LENGTH(alen);
        struct rtattr *rta;
@@ -634,9 +670,7 @@ static void inittun(void)
                // get the interface index
                struct {
                        struct nlmsghdr nh;
-                       struct ifinfomsg ifinfo __attribute__ ((aligned(NLMSG_ALIGNTO)));
-                       struct rtattr ifname_rta __attribute__ ((aligned(RTA_ALIGNTO)));
-                       char ifname[IFNAMSIZ];
+                       struct ifinfomsg ifinfo;
                } req;
                char buf[4096];
                ssize_t len;
@@ -674,7 +708,7 @@ static void inittun(void)
                        union {
                                struct ifinfomsg ifinfo;
                                struct ifaddrmsg ifaddr;
-                       } ifmsg __attribute__ ((aligned(NLMSG_ALIGNTO)));
+                       } ifmsg;
                        char rtdata[32]; // 32 should be enough
                } req;
                uint32_t txqlen, mtu;