X-Git-Url: https://git.decadent.org.uk/gitweb/?a=blobdiff_plain;f=src%2Fra.c;h=58c87417e2929ca91ee0cd23403462b05d44c2db;hb=68ac18ed5d5b4c2d403396764f08c92a160b4a18;hp=aa03ff4d3ab8f6235b38aa8f069c785d3486a10e;hpb=4a9de784477a0f0dbc04ff890e35adae02ee6e8b;p=odhcp6c.git

diff --git a/src/ra.c b/src/ra.c
index aa03ff4..58c8741 100644
--- a/src/ra.c
+++ b/src/ra.c
@@ -59,13 +59,23 @@ int ra_init(const char *ifname, const struct in6_addr *ifid)
 {
 	const pid_t ourpid = getpid();
 	sock = socket(AF_INET6, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_ICMPV6);
+	if (sock < 0)
+		return -1;
+
 	if_index = if_nametoindex(ifname);
+	if (!if_index)
+		return -1;
+
 	strncpy(if_name, ifname, sizeof(if_name) - 1);
 	lladdr = *ifid;
 
 	rtnl = socket(AF_NETLINK, SOCK_DGRAM | SOCK_CLOEXEC, NETLINK_ROUTE);
+	if (rtnl < 0)
+		return -1;
+
 	struct sockaddr_nl rtnl_kernel = { .nl_family = AF_NETLINK };
-	connect(rtnl, (const struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel));
+	if (connect(rtnl, (const struct sockaddr*)&rtnl_kernel, sizeof(rtnl_kernel)) < 0)
+		return -1;
 
 	int val = RTNLGRP_LINK;
 	setsockopt(rtnl, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &val, sizeof(val));
@@ -150,6 +160,7 @@ static void update_proc(const char *sect, const char *opt, uint32_t value)
 
 bool ra_link_up(void)
 {
+	static bool firstcall = true;
 	struct {
 		struct nlmsghdr hdr;
 		struct ifinfomsg msg;
@@ -161,19 +172,22 @@ bool ra_link_up(void)
 
 	do {
 		read = recv(rtnl, &resp, sizeof(resp), MSG_DONTWAIT);
-		if (!NLMSG_OK(&resp.hdr, read) || resp.hdr.nlmsg_type != RTM_NEWLINK ||
+		if (read < 0 || !NLMSG_OK(&resp.hdr, (size_t)read) ||
+				resp.hdr.nlmsg_type != RTM_NEWLINK ||
 				resp.msg.ifi_index != if_index)
 			continue;
 
 		bool hascarrier = resp.msg.ifi_flags & IFF_LOWER_UP;
-		if (nocarrier && hascarrier)
+		if (!firstcall && nocarrier != !hascarrier)
 			ret = true;
 
 		nocarrier = !hascarrier;
+		firstcall = false;
 	} while (read > 0);
 
 	if (ret) {
-		syslog(LOG_NOTICE, "carrier up event on %s", if_name);
+		syslog(LOG_NOTICE, "carrier => %i event on %s", (int)!nocarrier, if_name);
+
 		rs_attempt = 0;
 		ra_send_rs(SIGALRM);
 	}
@@ -181,6 +195,32 @@ bool ra_link_up(void)
 	return ret;
 }
 
+static bool ra_icmpv6_valid(struct sockaddr_in6 *source, int hlim, uint8_t *data, size_t len)
+{
+	struct icmp6_hdr *hdr = (struct icmp6_hdr*)data;
+	struct icmpv6_opt *opt, *end = (struct icmpv6_opt*)&data[len];
+
+	if (hlim != 255 || len < sizeof(*hdr) || hdr->icmp6_code)
+		return false;
+
+	switch (hdr->icmp6_type) {
+	case ND_ROUTER_ADVERT:
+		if (!IN6_IS_ADDR_LINKLOCAL(&source->sin6_addr))
+			return false;
+
+		opt = (struct icmpv6_opt*)((struct nd_router_advert*)data + 1);
+		break;
+
+	default:
+		return false;
+	}
+	
+	icmpv6_for_each_option(opt, opt, end)
+		;
+
+	return opt == end;
+}
+
 bool ra_process(void)
 {
 	bool found = false;
@@ -212,10 +252,8 @@ bool ra_process(void)
 				cmsg_buf, sizeof(cmsg_buf), 0};
 
 		ssize_t len = recvmsg(sock, &msg, MSG_DONTWAIT);
-		if (len < 0)
+		if (len <= 0)
 			break;
-		else if (len < (ssize_t)sizeof(*adv))
-			continue;
 
 		int hlim = 0;
 		for (struct cmsghdr *ch = CMSG_FIRSTHDR(&msg); ch != NULL;
@@ -224,7 +262,7 @@ bool ra_process(void)
 					ch->cmsg_type == IPV6_HOPLIMIT)
 				memcpy(&hlim, CMSG_DATA(ch), sizeof(hlim));
 
-		if (hlim != 255)
+		if (!ra_icmpv6_valid(&from, hlim, buf, len))
 			continue;
 
 		// Stop sending solicits
@@ -250,6 +288,10 @@ bool ra_process(void)
 		entry.preferred = entry.valid;
 		changed |= odhcp6c_update_entry(STATE_RA_ROUTE, &entry);
 
+		// Parse hoplimit
+		if (adv->nd_ra_curhoplimit)
+			update_proc("conf", "hop_limit", adv->nd_ra_curhoplimit);
+
 		// Parse ND parameters
 		if (ntohl(adv->nd_ra_reachable) <= 3600000)
 			update_proc("neigh", "base_reachable_time_ms", ntohl(adv->nd_ra_reachable));