I rewrote the interface handling code, so that it supports multiple

addresses per interface (needed for example for IPv6 support).

Visible changes:

o  struct iface now contains a list of all interface addresses (represented
   by struct ifa), iface->addr points to the primary address (if any).
o  Interface has IF_UP set iff it's up and it has a primary address.
o  IF_UP is now independent on IF_IGNORED (i.e., you need to test IF_IGNORED
   in the protocols; I've added this, but please check).
o  The if_notify_change hook has been simplified (only one interface pointer
   etc.).
o  Introduced a ifa_notify_change hook. (For now, only the Direct protocol
   does use it -- it's wise to just listen to device routes in all other
   protocols.)
o  Removed IF_CHANGE_FLAGS notifier flag (it was meaningless anyway).
o  Updated all the code except netlink (I'll look at it tomorrow) to match
   the new semantics (please look at your code to ensure I did it right).

Things to fix:

o  Netlink.
o  Make krt-iface interpret "eth0:1"-type aliases as secondary addresses.

2 files changed, 30 insertions, 22 deletions

diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index 7764d3d..6d44f80 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -414,14 +414,14 @@ sk_open(sock *s)
 #ifdef HAVE_STRUCT_IP_MREQN
 	struct ip_mreqn mreq;
 #define mreq_add mreq
-	ASSERT(s->iface);
+	ASSERT(s->iface && s->iface->addr);
 	mreq.imr_ifindex = s->iface->index;
-	set_inaddr(&mreq.imr_address, s->iface->ip);
+	set_inaddr(&mreq.imr_address, s->iface->addr->ip);
 #else
 	struct in_addr mreq;
 	struct ip_mreq mreq_add;
-	ASSERT(s->iface);
-	set_inaddr(&mreq, s->iface->ip);
+	ASSERT(s->iface && s->iface->addr);
+	set_inaddr(&mreq, s->iface->addr->ip);
 #ifdef SO_BINDTODEVICE
 	{
 	  struct ifreq ifr;
diff --git a/sysdep/unix/krt-iface.c b/sysdep/unix/krt-iface.c
index bca70cc..57692eb 100644
--- a/sysdep/unix/krt-iface.c
+++ b/sysdep/unix/krt-iface.c
@@ -30,7 +30,8 @@ int if_scan_sock = -1;
 static void
 scan_ifs(struct ifreq *r, int cnt)
 {
-  struct iface i;
+  struct iface i, *pi;
+  struct ifa a;
   char *err;
   unsigned fl;
   ip_addr netmask;
@@ -40,6 +41,7 @@ scan_ifs(struct ifreq *r, int cnt)
   for (cnt /= sizeof(struct ifreq); cnt; cnt--, r++)
     {
       bzero(&i, sizeof(i));
+      bzero(&a, sizeof(a));
       DBG("%s\n", r->ifr_name);
       if (strchr(r->ifr_name, ':'))
 	{
@@ -48,17 +50,21 @@ scan_ifs(struct ifreq *r, int cnt)
 	  continue;
 	}
       strncpy(i.name, r->ifr_name, sizeof(i.name) - 1);
-      get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &i.ip, NULL);
-      if (ipa_nonzero(i.ip))
+      get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.ip, NULL);
+      if (ipa_nonzero(a.ip))
 	{
-	  l = ipa_classify(i.ip);
+	  l = ipa_classify(a.ip);
 	  if (l < 0 || !(l & IADDR_HOST))
 	    {
 	      log(L_ERR "%s: Invalid interface address", i.name);
-	      i.ip = IPA_NONE;
+	      a.ip = IPA_NONE;
+	    }
+	  else
+	    {
+	      a.scope = l & IADDR_SCOPE_MASK;
+	      if (a.scope == SCOPE_HOST)
+		i.flags |= IF_LOOPBACK | IF_IGNORE;
 	    }
-	  else if ((l & IADDR_SCOPE_MASK) == SCOPE_HOST)
-	    i.flags |= IF_LOOPBACK | IF_IGNORE;
 	}
 
       if (ioctl(if_scan_sock, SIOCGIFFLAGS, r) < 0)
@@ -83,15 +89,15 @@ scan_ifs(struct ifreq *r, int cnt)
 	  log(L_ERR "%s: Invalid netmask", i.name);
 	  goto bad;
 	}
-      i.pxlen = l;
+      a.pxlen = l;
 
       if (fl & IFF_POINTOPOINT)
 	{
 	  i.flags |= IF_UNNUMBERED;
-	  i.pxlen = BITS_PER_IP_ADDRESS;
+	  a.pxlen = BITS_PER_IP_ADDRESS;
 	  if (ioctl(if_scan_sock, SIOCGIFDSTADDR, r) < 0)
 	    { err = "SIOCGIFDSTADDR"; goto faulty; }
-	  get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &i.opposite, NULL);
+	  get_sockaddr((struct sockaddr_in *) &r->ifr_addr, &a.opposite, NULL);
 	}
       if (fl & IFF_LOOPBACK)
 	i.flags |= IF_LOOPBACK | IF_IGNORE;
@@ -100,24 +106,24 @@ scan_ifs(struct ifreq *r, int cnt)
 #endif
 	i.flags |= IF_MULTICAST;
 
-      i.prefix = ipa_and(i.ip, ipa_mkmask(i.pxlen));
-      if (i.pxlen < 32)
+      a.prefix = ipa_and(a.ip, ipa_mkmask(a.pxlen));
+      if (a.pxlen < 32)
 	{
-	  i.brd = ipa_or(i.prefix, ipa_not(ipa_mkmask(i.pxlen)));
-	  if (ipa_equal(i.ip, i.prefix) || ipa_equal(i.ip, i.brd))
+	  a.brd = ipa_or(a.prefix, ipa_not(ipa_mkmask(a.pxlen)));
+	  if (ipa_equal(a.ip, a.prefix) || ipa_equal(a.ip, a.brd))
 	    {
 	      log(L_ERR "%s: Using network or broadcast address for interface", i.name);
 	      goto bad;
 	    }
 	  if (fl & IFF_BROADCAST)
 	    i.flags |= IF_BROADCAST;
-	  if (i.pxlen < 30)
+	  if (a.pxlen < 30)
 	    i.flags |= IF_MULTIACCESS;
 	  else
-	    i.opposite = ipa_opposite(i.ip);
+	    a.opposite = ipa_opposite(a.ip);
 	}
       else
-	i.brd = i.opposite;
+	a.brd = a.opposite;
 
       if (ioctl(if_scan_sock, SIOCGIFMTU, r) < 0)
 	{ err = "SIOCGIFMTU"; goto faulty; }
@@ -132,7 +138,9 @@ scan_ifs(struct ifreq *r, int cnt)
       /* FIXME: What else? Guess ifindex (we need it at least for OSPF on unnumbered links)? */
 #endif
 
-      if_update(&i);
+      pi = if_update(&i);
+      a.iface = pi;
+      ifa_update(&a);
     }
   if_end_update();
 }