X-Git-Url: http://git.sameswireless.fr/l2tpns.git/blobdiff_plain/ba87a9d8744d179dd7bc3a57cf8b1e506bcfae54..e6bf06aa1b0d74bf2d748dbff76192d11c328592:/l2tpns.c?ds=sidebyside

diff --git a/l2tpns.c b/l2tpns.c
index d849711..57e3215 100644
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -73,6 +73,7 @@ time_t basetime = 0;		// base clock
 char hostname[1000] = "";	// us.
 static int tunidx;		// ifr_ifindex of tun device
 int nlseqnum = 0;		// netlink sequence number
+int min_initok_nlseqnum = 0;	// minimun seq number for messages after init is ok
 static int syslog_log = 0;	// are we logging to syslog
 static FILE *log_stream = 0;	// file handle for direct logging (i.e. direct into file, not via syslog).
 uint32_t last_id = 0;		// Unique ID for radius accounting
@@ -540,7 +541,7 @@ static void initnetlink(void)
 	}
 }
 
-static ssize_t netlink_send(struct nlmsghdr *nh, int want_ack)
+static ssize_t netlink_send(struct nlmsghdr *nh)
 {
 	struct sockaddr_nl nladdr;
 	struct iovec iov;
@@ -548,8 +549,6 @@ static ssize_t netlink_send(struct nlmsghdr *nh, int want_ack)
 
 	nh->nlmsg_pid = getpid();
 	nh->nlmsg_seq = ++nlseqnum;
-	if (want_ack)
-		nh->nlmsg_flags |= NLM_F_ACK;
 
 	// set kernel address
 	memset(&nladdr, 0, sizeof(nladdr));
@@ -561,7 +560,7 @@ static ssize_t netlink_send(struct nlmsghdr *nh, int want_ack)
 	return sendmsg(nlfd, &msg, 0);
 }
 
-static ssize_t netlink_recv(char *buf, ssize_t len)
+static ssize_t netlink_recv(void *buf, ssize_t len)
 {
 	struct sockaddr_nl nladdr;
 	struct iovec iov;
@@ -577,50 +576,35 @@ static ssize_t netlink_recv(char *buf, ssize_t len)
 	return recvmsg(nlfd, &msg, 0);
 }
 
-static ssize_t netlink_check_ack(struct nlmsghdr *ack_nh, ssize_t len, int msg_count)
+/* adapted from iproute2 */
+void netlink_addattr(struct nlmsghdr *nh, int type, const void *data, int alen)
 {
-	uint32_t seqnum = 0;
-
-	// expect ack
-	for (; NLMSG_OK (ack_nh, len); ack_nh = NLMSG_NEXT (ack_nh, len))
-	{
-		if (ack_nh->nlmsg_type == NLMSG_DONE)
-			return msg_count != 0 || seqnum != nlseqnum;
-			// 1 => lost an ack
-
-		if (ack_nh->nlmsg_type == NLMSG_ERROR)
-		{
-			struct nlmsgerr *errmsg = NLMSG_DATA(ack_nh);
-			if (errmsg->error)
-				return errmsg->error; // got an error back
-			else
-			{
-				// ack received
-				--msg_count;
-				if (errmsg->msg.nlmsg_seq > seqnum);
-					seqnum = errmsg->msg.nlmsg_seq;
-				// if this is a single message, return now
-				if (!(ack_nh->nlmsg_flags & NLM_F_MULTI))
-					return msg_count != 0 || seqnum != nlseqnum;
-			}
-		}
-		else
-			// unknown message
-			LOG(3, 0, 0, "Got an unknown netlink message: type %d\n", ack_nh->nlmsg_type);
-	}
-
-	return 1; // malformed message?!
+	int len = RTA_LENGTH(alen);
+	struct rtattr *rta;
+
+	rta = (struct rtattr *)(((void *)nh) + NLMSG_ALIGN(nh->nlmsg_len));
+	rta->rta_type = type;
+	rta->rta_len = len;
+	memcpy(RTA_DATA(rta), data, alen);
+	nh->nlmsg_len = NLMSG_ALIGN(nh->nlmsg_len) + RTA_ALIGN(len);
 }
 
+// messages corresponding to different phases seq number
+static char *tun_nl_phase_msg[] = {
+	"initialized",
+	"getting tun interface index",
+	"setting tun interface parameters",
+	"setting tun IPv4 address",
+	"setting tun LL IPv6 address",
+	"setting tun global IPv6 address",
+};
+
 //
 // Set up TUN interface
 static void inittun(void)
 {
 	struct ifinfomsg ifinfo;
 	struct ifreq ifr;
-	char buf[4096];
-	ssize_t len;
-	struct nlmsghdr *resp_nh;
 
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_flags = IFF_TUN;
@@ -640,8 +624,8 @@ static void inittun(void)
 		LOG(0, 0, 0, "Can't set tun interface: %s\n", strerror(errno));
 		exit(1);
 	}
-	assert(strlen(ifr.ifr_name) < sizeof(config->tundevice));
-	strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice) - 1);
+	assert(strlen(ifr.ifr_name) < sizeof(config->tundevice) - 1);
+	strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice));
 
 	{
 		// get the interface index
@@ -651,20 +635,19 @@ static void inittun(void)
 			struct rtattr ifname_rta __attribute__ ((aligned(RTA_ALIGNTO)));
 			char ifname[IFNAMSIZ];
 		} req;
+		char buf[4096];
+		ssize_t len;
+		struct nlmsghdr *resp_nh;
 
 		req.nh.nlmsg_type = RTM_GETLINK;
 		req.nh.nlmsg_flags = NLM_F_REQUEST;
+		req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifinfo));
 
 		req.ifinfo.ifi_family = AF_UNSPEC; // as the man says
 
-		req.ifname_rta.rta_len = RTA_LENGTH(strlen(config->tundevice)+1);
-		req.ifname_rta.rta_type = IFLA_IFNAME;
-		strncpy(req.ifname, config->tundevice, IFNAMSIZ-1);
-
-		req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifinfo)
-				+ req.ifname_rta.rta_len);
+		netlink_addattr(&req.nh, IFLA_IFNAME, config->tundevice, strlen(config->tundevice)+1);
 
-		if(netlink_send(&req.nh, 0) < 0 || (len = netlink_recv(buf, sizeof(buf))) < 0)
+		if(netlink_send(&req.nh) < 0 || (len = netlink_recv(buf, sizeof(buf))) < 0)
 		{
 			LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
 			exit(1);
@@ -673,7 +656,7 @@ static void inittun(void)
 		resp_nh = (struct nlmsghdr *)buf;
 		if (!NLMSG_OK (resp_nh, len))
 		{
-			LOG(0, 0, 0, "Malformed answer getting tun ifindex\n");
+			LOG(0, 0, 0, "Malformed answer getting tun ifindex %ld\n", len);
 			exit(1);
 		}
 
@@ -682,7 +665,6 @@ static void inittun(void)
 		tunidx = ifinfo.ifi_index;
 	}
 	{
-		ssize_t err;
 		struct {
 			// interface setting
 			struct nlmsghdr nh;
@@ -692,175 +674,114 @@ static void inittun(void)
 			} ifmsg __attribute__ ((aligned(NLMSG_ALIGNTO)));
 			char rtdata[32]; // 32 should be enough
 		} req;
-		struct {
-			struct rtattr rta;
-			uint32_t u32 __attribute__ ((aligned(RTA_ALIGNTO)));;
-		} u32_attr;
-		struct {
-			struct rtattr rta;
-			struct in_addr addr __attribute__ ((aligned(RTA_ALIGNTO)));;
-		} ipv4_attr;
-		struct {
-			struct rtattr rta;
-			struct in6_addr addr6 __attribute__ ((aligned(RTA_ALIGNTO)));;
-		} ipv6_attr;
-		char buf[256];
-		ssize_t buf_len;
-		char *buf_ptr;
+		uint32_t txqlen, mtu;
+		struct in_addr ip;
 
 		memset(&req, 0, sizeof(req));
 
 		req.nh.nlmsg_type = RTM_SETLINK;
 		req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_MULTI;
+		req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifinfo));
 
 		req.ifmsg.ifinfo = ifinfo;
 		req.ifmsg.ifinfo.ifi_flags |= IFF_UP; // set interface up
 		req.ifmsg.ifinfo.ifi_change = IFF_UP; // only change this flag
 
-		buf_ptr = NLMSG_DATA(&req.nh) + sizeof(req.ifmsg.ifinfo);
-
-		u32_attr.rta.rta_len = RTA_LENGTH(sizeof(u32_attr.u32));
-		u32_attr.rta.rta_type = IFLA_TXQLEN;
 		/* Bump up the qlen to deal with bursts from the network */
-		u32_attr.u32 = 1000;
-		memcpy(buf_ptr, &u32_attr, sizeof(u32_attr));
-
-		buf_ptr += RTA_ALIGN(u32_attr.rta.rta_len);
-
-		u32_attr.rta.rta_len = RTA_LENGTH(sizeof(u32_attr.u32));
-		u32_attr.rta.rta_type = IFLA_MTU;
+		txqlen = 1000;
+		netlink_addattr(&req.nh, IFLA_TXQLEN, &txqlen, sizeof(txqlen));
 		/* set MTU to modem MRU */
-		u32_attr.u32 = MRU;
-		memcpy(buf_ptr, &u32_attr, sizeof(u32_attr));
-
-		req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifinfo)
-				+ u32_attr.rta.rta_len * 2);
+		mtu = MRU;
+		netlink_addattr(&req.nh, IFLA_MTU, &mtu, sizeof(mtu));
 
-		if (netlink_send(&req.nh, 1) < 0)
-		{
-			LOG(0, 0, 0, "Error setting up tun device interface: %s\n", strerror(errno));
-			exit(1);
-		}
+		if (netlink_send(&req.nh) < 0)
+			goto senderror;
 
 		memset(&req, 0, sizeof(req));
 
 		req.nh.nlmsg_type = RTM_NEWADDR;
 		req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_MULTI;
+		req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr));
 
 		req.ifmsg.ifaddr.ifa_family = AF_INET;
 		req.ifmsg.ifaddr.ifa_prefixlen = 32;
 		req.ifmsg.ifaddr.ifa_index = ifinfo.ifi_index;
 
-		ipv4_attr.rta.rta_len = RTA_LENGTH(sizeof(ipv4_attr.addr));
-		ipv4_attr.rta.rta_type = IFA_ADDRESS;
-		ipv4_attr.addr.s_addr = config->bind_address ?
-			config->bind_address : 0x01010101; // 1.1.1.1
-		memcpy(NLMSG_DATA(&req.nh) + sizeof(req.ifmsg.ifaddr), &ipv4_attr, sizeof(ipv4_attr));
-
-		req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr)
-				+ ipv4_attr.rta.rta_len);
-
-		if (netlink_send(&req.nh, 1) < 0)
-		{
-			LOG(0, 0, 0, "Error setting up tun device IPv4 address: %s\n", strerror(errno));
-			exit(1);
-		}
+		if (config->bind_address)
+			ip.s_addr = config->bind_address;
+		else
+			ip.s_addr = 0x01010101, // 1.1.1.1
+		netlink_addattr(&req.nh, IFA_LOCAL, &ip, sizeof(ip));
 
-		memset(&req, 0, sizeof(req));
+		if (netlink_send(&req.nh) < 0)
+			goto senderror;
 
 		// Only setup IPv6 on the tun device if we have a configured prefix
 		if (config->ipv6_prefix.s6_addr[0]) {
+			struct in6_addr ip6;
+
+			memset(&req, 0, sizeof(req));
+
 			req.nh.nlmsg_type = RTM_NEWADDR;
 			req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_MULTI;
+			req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr));
 
 			req.ifmsg.ifaddr.ifa_family = AF_INET6;
 			req.ifmsg.ifaddr.ifa_prefixlen = 64;
 			req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_LINK;
 			req.ifmsg.ifaddr.ifa_index = ifinfo.ifi_index;
 
-			ipv6_attr.rta.rta_len = RTA_LENGTH(sizeof(ipv6_attr.addr6));
-			ipv6_attr.rta.rta_type = IFA_LOCAL;
 			// Link local address is FE80::1
-			memset(&ipv6_attr.addr6, 0, sizeof(ipv6_attr.addr6));
-			ipv6_attr.addr6.s6_addr[0] = 0xFE;
-			ipv6_attr.addr6.s6_addr[1] = 0x80;
-			ipv6_attr.addr6.s6_addr[15] = 1;
-			memcpy(NLMSG_DATA(&req.nh) + sizeof(req.ifmsg.ifaddr), &ipv6_attr, sizeof(ipv6_attr));
+			memset(&ip6, 0, sizeof(ip6));
+			ip6.s6_addr[0] = 0xFE;
+			ip6.s6_addr[1] = 0x80;
+			ip6.s6_addr[15] = 1;
+			netlink_addattr(&req.nh, IFA_LOCAL, &ip6, sizeof(ip6));
 
-			req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr)
-					+ ipv6_attr.rta.rta_len);
-
-			if (netlink_send(&req.nh, 1) < 0)
-			{
-				LOG(0, 0, 0, "Error setting up tun device IPv6 LL address: %s\n", strerror(errno));
-				exit(1);
-			}
+			if (netlink_send(&req.nh) < 0)
+				goto senderror;
 
 			memset(&req, 0, sizeof(req));
 
 			req.nh.nlmsg_type = RTM_NEWADDR;
 			req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_MULTI;
+			req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr));
 
 			req.ifmsg.ifaddr.ifa_family = AF_INET6;
 			req.ifmsg.ifaddr.ifa_prefixlen = 64;
 			req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE;
 			req.ifmsg.ifaddr.ifa_index = ifinfo.ifi_index;
 
-			ipv6_attr.rta.rta_len = RTA_LENGTH(sizeof(ipv6_attr.addr6));
-			ipv6_attr.rta.rta_type = IFA_LOCAL;
 			// Global address is prefix::1
-			ipv6_attr.addr6 = config->ipv6_prefix;
-			ipv6_attr.addr6.s6_addr[15] = 1;
-			memcpy(NLMSG_DATA(&req.nh) + sizeof(req.ifmsg.ifaddr), &ipv6_attr, sizeof(ipv6_attr));
+			ip6 = config->ipv6_prefix;
+			ip6.s6_addr[15] = 1;
+			netlink_addattr(&req.nh, IFA_LOCAL, &ip6, sizeof(ip6));
 
-			req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifaddr)
-					+ ipv6_attr.rta.rta_len);
-
-			if (netlink_send(&req.nh, 1) < 0)
-			{
-				LOG(0, 0, 0, "Error setting up tun device IPv6 global address: %s\n", strerror(errno));
-				exit(1);
-			}
-
-			memset(&req, 0, sizeof(req));
+			if (netlink_send(&req.nh) < 0)
+				goto senderror;
 		}
 
+		memset(&req, 0, sizeof(req));
+
 		req.nh.nlmsg_type = NLMSG_DONE;
 		req.nh.nlmsg_len = NLMSG_LENGTH(0);
 
-		if (netlink_send(&req.nh, 1) < 0)
-		{
-			LOG(0, 0, 0, "Error finishing setting up tun device: %s\n", strerror(errno));
-			exit(1);
-		}
+		if (netlink_send(&req.nh) < 0)
+			goto senderror;
 
-		buf_ptr = buf;
-		buf_len = sizeof(buf);
-		do
-		{
-			len = netlink_recv(buf_ptr, sizeof(buf_len));
-			if (len < 0)
-			{
-				LOG(0, 0, 0, "Error waiting for ack setting up tun device: %s\n", strerror(errno));
-				exit(1);
-			}
+		// if we get an error for seqnum < min_initok_nlseqnum,
+		// we must exit as initialization went wrong
+		if (config->ipv6_prefix.s6_addr[0])
+			min_initok_nlseqnum = 5 + 1; // idx + if + addr + 2*addr6
+		else
+			min_initok_nlseqnum = 3 + 1; // idx + if + addr
+	}
 
-			resp_nh = (struct nlmsghdr *)buf_ptr;
-			buf_len -= len;
-			buf_ptr += len;
-		}
-		while (buf_len > 0 && (resp_nh->nlmsg_flags & NLM_F_MULTI)
-				&& resp_nh->nlmsg_type != NLMSG_DONE);
+	return;
 
-		if ((err = netlink_check_ack((struct nlmsghdr *)buf, buf_len, 4)))
-		{
-			if (err < 0)
-				LOG(0, 0, 0, "Error while receiving tun device ack: %s\n", strerror(errno));
-			else
-				LOG(0, 0, 0, "Error while receiving tun device ack\n");
-			exit(1);
-		}
-	}
+senderror:
+	LOG(0, 0, 0, "Error while setting up tun device: %s\n", strerror(errno));
+	exit(1);
 }
 
 // set up UDP ports
@@ -3736,8 +3657,8 @@ static int still_busy(void)
 # include "fake_epoll.h"
 #endif
 
-// the base set of fds polled: cli, cluster, tun, udp, control, dae
-#define BASE_FDS	6
+// the base set of fds polled: cli, cluster, tun, udp, control, dae, netlink
+#define BASE_FDS	7
 
 // additional polled fds
 #ifdef BGP
@@ -3761,8 +3682,8 @@ static void mainloop(void)
 		exit(1);
 	}
 
-	LOG(4, 0, 0, "Beginning of main loop.  clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d\n",
-		clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd);
+	LOG(4, 0, 0, "Beginning of main loop.  clifd=%d, cluster_sockfd=%d, tunfd=%d, udpfd=%d, controlfd=%d, daefd=%d, nlfd=%d\n",
+		clifd, cluster_sockfd, tunfd, udpfd, controlfd, daefd, nlfd);
 
 	/* setup our fds to poll for input */
 	{
@@ -3798,6 +3719,10 @@ static void mainloop(void)
 		d[i].type = FD_TYPE_DAE;
 		e.data.ptr = &d[i++];
 		epoll_ctl(epollfd, EPOLL_CTL_ADD, daefd, &e);
+
+		d[i].type = FD_TYPE_NETLINK;
+		e.data.ptr = &d[i++];
+		epoll_ctl(epollfd, EPOLL_CTL_ADD, nlfd, &e);
 	}
 
 #ifdef BGP
@@ -3934,6 +3859,32 @@ static void mainloop(void)
 					break;
 #endif /* BGP */
 
+				case FD_TYPE_NETLINK:
+				{
+					struct nlmsghdr *nh = (struct nlmsghdr *)buf;
+					s = netlink_recv(buf, sizeof(buf));
+					if (nh->nlmsg_type == NLMSG_ERROR)
+					{
+						struct nlmsgerr *errmsg = NLMSG_DATA(nh);
+						if (errmsg->error)
+						{
+							if (errmsg->msg.nlmsg_seq < min_initok_nlseqnum)
+							{
+								LOG(0, 0, 0, "Got a fatal netlink error (while %s): %s\n", tun_nl_phase_msg[nh->nlmsg_seq], strerror(-errmsg->error));
+								exit(1);
+							}
+							else
+
+								LOG(0, 0, 0, "Got a netlink error: %s\n", strerror(-errmsg->error));
+						}
+						// else it's a ack
+					}
+					else
+						LOG(1, 0, 0, "Got a unknown netlink message: type %d seq %d flags %d\n", nh->nlmsg_type, nh->nlmsg_seq, nh->nlmsg_flags);
+					n--;
+					break;
+				}
+
 				default:
 				    	LOG(0, 0, 0, "Unexpected fd type returned from epoll_wait: %d\n", d->type);
 				}