Netlink module supports interface scan on startup. Working on more. (7972248d) · Commits · 戴 / Bird

TODO

+3 −3

Original line number	Diff line number	Diff line
		@@ -19,12 +19,12 @@ Core

		- incoming packets: interface the packet came from? (esp. for multicasts)
		- broadcast/multicast echoing suppresion
		- we need ifindex at least for PtP links

		- kernel: RTM_DELROUTE not announced for device routes [confirmed by Alexey: it's a feature]

		- netlink: import Linux route attributes to our rta's, so that they can be filtered?

		- iface: when seen an invalid broadcast, fix it up or at least report
		- iface: we always need ifindex at least for PtP links (OSPF)

		Cleanup
		~~~~~~~
		- right usage of DBG vs. debug

sysdep/linux/netlink/krt.c

+120 −5

Original line number	Diff line number	Diff line
		@@ -9,6 +9,7 @@
		#include <string.h>
		#include <stdio.h>
		#include <fcntl.h>
		#include <net/if.h>
		#include <sys/socket.h>
		#include <sys/uio.h>

		@@ -102,6 +103,11 @@ nl_get_reply(void)
		int x = recvmsg(nl_sync_fd, &m, 0);
		if (x < 0)
		die("nl_get_reply: %m");
		if (sa.nl_pid) /* It isn't from the kernel */
		{
		DBG("Non-kernel packet\n");
		continue;
		}
		nl_last_size = x;
		nl_last_hdr = (void *) nl_rx_buffer;
		if (m.msg_flags & MSG_TRUNC)
		@@ -193,14 +199,63 @@ nl_parse_attrs(struct rtattr a, struct rtattr *k, int ksize)
		*/

		static void
		nl_parse_link(struct nlmsghdr *h)
		nl_parse_link(struct nlmsghdr *h, int scan)
		{
		struct ifinfomsg *i;
		struct rtattr *a[IFLA_STATS+1];
		int new = h->nlmsg_type == RTM_NEWLINK;
		struct iface f;
		struct iface *ifi;
		char *name;
		u32 mtu;
		unsigned int fl;

		if (!(i = nl_checkin(h, sizeof(*i))) \|\| !nl_parse_attrs(IFLA_RTA(i), a, sizeof(a)))
		return;
		DBG("NEWLINK %d\n", i->ifi_index);
		if (!a[IFLA_IFNAME] \|\| RTA_PAYLOAD(a[IFLA_IFNAME]) < 2 \|\|
		!a[IFLA_MTU] \|\| RTA_PAYLOAD(a[IFLA_MTU]) != 4)
		{
		log(L_ERR "nl_parse_link: Malformed message received");
		return;
		}
		name = RTA_DATA(a[IFLA_IFNAME]);
		memcpy(&mtu, RTA_DATA(a[IFLA_MTU]), sizeof(u32));

		ifi = if_find_by_index(i->ifi_index);
		if (!new)
		{
		DBG("KRT: IF%d(%s) goes down\n", i->ifi_index, name);
		if (ifi && !scan)
		{
		memcpy(&f, ifi, sizeof(struct iface));
		f.flags \|= IF_ADMIN_DOWN;
		if_update(&f);
		}
		}
		else
		{
		DBG("KRT: IF%d(%s) goes up (mtu=%d,flg=%x)\n", i->ifi_index, name, mtu, i->ifi_flags);
		if (ifi)
		memcpy(&f, ifi, sizeof(f));
		else
		{
		bzero(&f, sizeof(f));
		f.index = i->ifi_index;
		}
		strncpy(f.name, RTA_DATA(a[IFLA_IFNAME]), sizeof(f.name)-1);
		f.mtu = mtu;
		f.flags = 0;
		fl = i->ifi_flags;
		if (fl & IFF_UP)
		f.flags \|= IF_LINK_UP;
		if (fl & IFF_POINTOPOINT)
		f.flags \|= IF_UNNUMBERED \| IF_MULTICAST;
		if (fl & IFF_LOOPBACK)
		f.flags \|= IF_LOOPBACK \| IF_IGNORE;
		if (fl & IFF_BROADCAST)
		f.flags \|= IF_BROADCAST \| IF_MULTICAST;
		if_update(&f);
		}
		}

		static void
		@@ -208,10 +263,68 @@ nl_parse_addr(struct nlmsghdr *h)
		{
		struct ifaddrmsg *i;
		struct rtattr *a[IFA_ANYCAST+1];
		int new = h->nlmsg_type == RTM_NEWADDR;
		struct iface f;
		struct iface *ifi;

		if (!(i = nl_checkin(h, sizeof(*i))) \|\| !nl_parse_attrs(IFA_RTA(i), a, sizeof(a)))
		return;
		DBG("NEWADDR %d\n", i->ifa_index);
		if (i->ifa_family != AF_INET)
		return;
		if (!a[IFA_ADDRESS] \|\| RTA_PAYLOAD(a[IFA_ADDRESS]) != 4 \|\|
		!a[IFA_LOCAL] \|\| RTA_PAYLOAD(a[IFA_LOCAL]) != 4 \|\|
		(a[IFA_BROADCAST] && RTA_PAYLOAD(a[IFA_BROADCAST]) != 4))
		{
		log(L_ERR "nl_parse_addr: Malformed message received");
		return;
		}
		if (i->ifa_flags & IFA_F_SECONDARY)
		{
		DBG("KRT: Received address message for secondary address which is not supported.\n"); /* FIXME */
		return;
		}

		ifi = if_find_by_index(i->ifa_index);
		if (!ifi)
		{
		log(L_ERR "KRT: Received address message for unknown interface %d\n", i->ifa_index);
		return;
		}
		memcpy(&f, ifi, sizeof(f));

		if (i->ifa_prefixlen > 32 \|\| i->ifa_prefixlen == 31 \|\|
		(f.flags & IF_UNNUMBERED) && i->ifa_prefixlen != 32)
		{
		log(L_ERR "KRT: Invalid prefix length for interface %s: %d\n", f.name, i->ifa_prefixlen);
		new = 0;
		}

		f.ip = f.brd = f.opposite = IPA_NONE;
		if (!new)
		{
		DBG("KRT: IF%d IP address deleted\n");
		f.pxlen = 0;
		}
		else
		{
		memcpy(&f.ip, RTA_DATA(a[IFA_LOCAL]), sizeof(f.ip));
		f.ip = ipa_ntoh(f.ip);
		f.pxlen = i->ifa_prefixlen;
		if (f.flags & IF_UNNUMBERED)
		{
		memcpy(&f.opposite, RTA_DATA(a[IFA_ADDRESS]), sizeof(f.opposite));
		f.opposite = f.brd = ipa_ntoh(f.opposite);
		}
		else if ((f.flags & IF_BROADCAST) && a[IFA_BROADCAST])
		{
		memcpy(&f.brd, RTA_DATA(a[IFA_BROADCAST]), sizeof(f.brd));
		f.brd = ipa_ntoh(f.brd);
		}
		/* else a NBMA link */
		f.prefix = ipa_and(f.ip, ipa_mkmask(f.pxlen));
		DBG("KRT: IF%d IP address set to %I, net %I/%d, brd %I, opp %I\n", f.index, f.ip, f.prefix, f.pxlen, f.brd, f.opposite);
		}
		if_update(&f);
		}

		static void
		@@ -219,10 +332,12 @@ nl_scan_ifaces(void)
		{
		struct nlmsghdr *h;

		if_start_update();

		nl_request_dump(RTM_GETLINK);
		while (h = nl_get_scan())
		if (h->nlmsg_type == RTM_NEWLINK \|\| h->nlmsg_type == RTM_DELLINK)
		nl_parse_link(h);
		nl_parse_link(h, 1);
		else
		log(L_DEBUG "nl_scan_ifaces: Unknown packet received (type=%d)", h->nlmsg_type);

		@@ -233,7 +348,7 @@ nl_scan_ifaces(void)
		else
		log(L_DEBUG "nl_scan_ifaces: Unknown packet received (type=%d)", h->nlmsg_type);

		bug("NIIDW");
		if_end_update();
		}

		/*

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