Solve the ``first connection'' problem that occurs on

demand-dial links with dynamic IP numbers where the program
that causes the dial bind()s to an interface address that is
subsequently changed after ppp negotiation.

The problem is defeated by adding negotiated addresses to the
tun interface as additional alias addresses and providing a set
of ``iface'' commands for managing the interface.  Libalias is
also required (and what a name clash!) - it happily IP-aliases
the address so that the source is that of the primary (negotiated)
interface and un-IP-aliases it on the way back.

An ``enable iface-alias'' is done implicitly by the -alias command
line switch.  If -alias isn't given, iface-aliasing is disabled by
default and can't be enabled 'till an ``alias enable yes'' is done.
``alias enable no'' silently disables iface-alias.

So, for dynamic-IP-type-connections, running ``ppp -alias -auto blah''
will work for the first connection, although existing bindings will
not survive a disconnect/connect as the TCP peer will be trying to
send to the old IP address - the packets won't route.

It's now a lot easier to add IPXCP to ppp with minor updates to
the new iface.[ch] (if anyone ever gets 'round to it).

It's also now possible to manually add interface aliases with
something like ``iface add 1.2.3.4/24 5.6.7.8''.  This allows
multi-homed ppp links :-)

1 files changed, 41 insertions, 94 deletions

diff --git a/usr.sbin/ppp/bundle.c b/usr.sbin/ppp/bundle.c
index 569d893..28da452 100644
--- a/usr.sbin/ppp/bundle.c
+++ b/usr.sbin/ppp/bundle.c
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: bundle.c,v 1.34 1998/08/26 17:39:36 brian Exp $
+ *	$Id: bundle.c,v 1.35 1998/09/17 00:45:25 brian Exp $
  */
 
 #include <sys/param.h>
@@ -89,6 +89,7 @@
 #include "cbcp.h"
 #include "datalink.h"
 #include "ip.h"
+#include "iface.h"
 
 #define SCATTER_SEGMENTS 4	/* version, datalink, name, physical */
 #define SOCKET_OVERHEAD	100	/* additional buffer space for large */
@@ -148,49 +149,6 @@ bundle_NewPhase(struct bundle *bundle, u_int new)
   }
 }
 
-static int
-bundle_CleanInterface(const struct bundle *bundle)
-{
-  int s;
-  struct ifreq ifrq;
-  struct ifaliasreq ifra;
-
-  s = ID0socket(AF_INET, SOCK_DGRAM, 0);
-  if (s < 0) {
-    log_Printf(LogERROR, "bundle_CleanInterface: socket(): %s\n",
-              strerror(errno));
-    return (-1);
-  }
-  strncpy(ifrq.ifr_name, bundle->ifp.Name, sizeof ifrq.ifr_name - 1);
-  ifrq.ifr_name[sizeof ifrq.ifr_name - 1] = '\0';
-  while (ID0ioctl(s, SIOCGIFADDR, &ifrq) == 0) {
-    memset(&ifra.ifra_mask, '\0', sizeof ifra.ifra_mask);
-    strncpy(ifra.ifra_name, bundle->ifp.Name, sizeof ifra.ifra_name - 1);
-    ifra.ifra_name[sizeof ifra.ifra_name - 1] = '\0';
-    ifra.ifra_addr = ifrq.ifr_addr;
-    if (ID0ioctl(s, SIOCGIFDSTADDR, &ifrq) < 0) {
-      if (ifra.ifra_addr.sa_family == AF_INET)
-        log_Printf(LogERROR, "Can't get dst for %s on %s !\n",
-                  inet_ntoa(((struct sockaddr_in *)&ifra.ifra_addr)->sin_addr),
-                  bundle->ifp.Name);
-      close(s);
-      return 0;
-    }
-    ifra.ifra_broadaddr = ifrq.ifr_dstaddr;
-    if (ID0ioctl(s, SIOCDIFADDR, &ifra) < 0) {
-      if (ifra.ifra_addr.sa_family == AF_INET)
-        log_Printf(LogERROR, "Can't delete %s address on %s !\n",
-                  inet_ntoa(((struct sockaddr_in *)&ifra.ifra_addr)->sin_addr),
-                  bundle->ifp.Name);
-      close(s);
-      return 0;
-    }
-  }
-  close(s);
-
-  return 1;
-}
-
 static void
 bundle_LayerStart(void *v, struct fsm *fp)
 {
@@ -387,14 +345,14 @@ bundle_LayerUp(void *v, struct fsm *fp)
     if (bundle->ncp.mp.active) {
       struct datalink *dl;
 
-      bundle->ifp.Speed = 0;
+      bundle->ifSpeed = 0;
       for (dl = bundle->links; dl; dl = dl->next)
         if (dl->state == DATALINK_OPEN)
-          bundle->ifp.Speed += modem_Speed(dl->physical);
+          bundle->ifSpeed += modem_Speed(dl->physical);
       tun_configure(bundle, bundle->ncp.mp.peer_mrru);
       bundle->autoload.running = 1;
     } else {
-      bundle->ifp.Speed = modem_Speed(p);
+      bundle->ifSpeed = modem_Speed(p);
       tun_configure(bundle, fsm2lcp(fp)->his_mru);
     }
   } else if (fp->proto == PROTO_IPCP) {
@@ -424,15 +382,15 @@ bundle_LayerDown(void *v, struct fsm *fp)
       struct datalink *dl;
       struct datalink *lost;
 
-      bundle->ifp.Speed = 0;
+      bundle->ifSpeed = 0;
       lost = NULL;
       for (dl = bundle->links; dl; dl = dl->next)
         if (fp == &dl->physical->link.lcp.fsm)
           lost = dl;
         else if (dl->state == DATALINK_OPEN)
-          bundle->ifp.Speed += modem_Speed(dl->physical);
+          bundle->ifSpeed += modem_Speed(dl->physical);
 
-      if (bundle->ifp.Speed)
+      if (bundle->ifSpeed)
         /* Don't configure down to a speed of 0 */
         tun_configure(bundle, bundle->ncp.mp.link.lcp.his_mru);
 
@@ -769,10 +727,11 @@ struct bundle *
 bundle_Create(const char *prefix, int type, const char **argv)
 {
   int s, enoentcount, err;
+  const char *ifname;
   struct ifreq ifrq;
   static struct bundle bundle;		/* there can be only one */
 
-  if (bundle.ifp.Name != NULL) {	/* Already allocated ! */
+  if (bundle.iface != NULL) {	/* Already allocated ! */
     log_Printf(LogALERT, "bundle_Create:  There's only one BUNDLE !\n");
     return NULL;
   }
@@ -811,24 +770,32 @@ bundle_Create(const char *prefix, int type, const char **argv)
     return NULL;
   }
 
-  bundle.ifp.Name = strrchr(bundle.dev.Name, '/');
-  if (bundle.ifp.Name == NULL)
-    bundle.ifp.Name = bundle.dev.Name;
+  ifname = strrchr(bundle.dev.Name, '/');
+  if (ifname == NULL)
+    ifname = bundle.dev.Name;
   else
-    bundle.ifp.Name++;
+    ifname++;
+
+  bundle.iface = iface_Create(ifname);
+  if (bundle.iface == NULL) {
+    close(s);
+    close(bundle.dev.fd);
+    return NULL;
+  }
 
   /*
    * Now, bring up the interface.
    */
   memset(&ifrq, '\0', sizeof ifrq);
-  strncpy(ifrq.ifr_name, bundle.ifp.Name, sizeof ifrq.ifr_name - 1);
+  strncpy(ifrq.ifr_name, ifname, sizeof ifrq.ifr_name - 1);
   ifrq.ifr_name[sizeof ifrq.ifr_name - 1] = '\0';
   if (ID0ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
     log_Printf(LogERROR, "bundle_Create: ioctl(SIOCGIFFLAGS): %s\n",
 	      strerror(errno));
     close(s);
+    iface_Destroy(bundle.iface);
+    bundle.iface = NULL;
     close(bundle.dev.fd);
-    bundle.ifp.Name = NULL;
     return NULL;
   }
   ifrq.ifr_flags |= IFF_UP;
@@ -836,22 +803,17 @@ bundle_Create(const char *prefix, int type, const char **argv)
     log_Printf(LogERROR, "bundle_Create: ioctl(SIOCSIFFLAGS): %s\n",
 	      strerror(errno));
     close(s);
+    iface_Destroy(bundle.iface);
+    bundle.iface = NULL;
     close(bundle.dev.fd);
-    bundle.ifp.Name = NULL;
     return NULL;
   }
 
   close(s);
 
-  if ((bundle.ifp.Index = GetIfIndex(bundle.ifp.Name)) < 0) {
-    log_Printf(LogERROR, "Can't find interface index.\n");
-    close(bundle.dev.fd);
-    bundle.ifp.Name = NULL;
-    return NULL;
-  }
-  log_Printf(LogPHASE, "Using interface: %s\n", bundle.ifp.Name);
+  log_Printf(LogPHASE, "Using interface: %s\n", ifname);
 
-  bundle.ifp.Speed = 0;
+  bundle.ifSpeed = 0;
 
   bundle.routing_seq = 0;
   bundle.phase = PHASE_DEAD;
@@ -882,8 +844,9 @@ bundle_Create(const char *prefix, int type, const char **argv)
   bundle.links = datalink_Create("deflink", &bundle, type);
   if (bundle.links == NULL) {
     log_Printf(LogALERT, "Cannot create data link: %s\n", strerror(errno));
+    iface_Destroy(bundle.iface);
+    bundle.iface = NULL;
     close(bundle.dev.fd);
-    bundle.ifp.Name = NULL;
     return NULL;
   }
 
@@ -917,7 +880,7 @@ bundle_Create(const char *prefix, int type, const char **argv)
   memset(&bundle.choked.timer, '\0', sizeof bundle.choked.timer);
 
   /* Clean out any leftover crud */
-  bundle_CleanInterface(&bundle);
+  iface_Clear(bundle.iface, IFACE_CLEAR_ALL);
 
   bundle_LockTun(&bundle);
 
@@ -939,7 +902,7 @@ bundle_DownInterface(struct bundle *bundle)
   }
 
   memset(&ifrq, '\0', sizeof ifrq);
-  strncpy(ifrq.ifr_name, bundle->ifp.Name, sizeof ifrq.ifr_name - 1);
+  strncpy(ifrq.ifr_name, bundle->iface->name, sizeof ifrq.ifr_name - 1);
   ifrq.ifr_name[sizeof ifrq.ifr_name - 1] = '\0';
   if (ID0ioctl(s, SIOCGIFFLAGS, &ifrq) < 0) {
     log_Printf(LogERROR, "bundle_DownInterface: ioctl(SIOCGIFFLAGS): %s\n",
@@ -985,7 +948,8 @@ bundle_Destroy(struct bundle *bundle)
   /* In case we never made PHASE_NETWORK */
   bundle_Notify(bundle, EX_ERRDEAD);
 
-  bundle->ifp.Name = NULL;
+  iface_Destroy(bundle->iface);
+  bundle->iface = NULL;
 }
 
 struct rtmsg {
@@ -1032,24 +996,10 @@ bundle_SetRoute(struct bundle *bundle, int cmd, struct in_addr dst,
   cp += rtdata.sin_len;
   if (cmd == RTM_ADD) {
     if (gateway.s_addr == INADDR_ANY) {
-      /* Add a route through the interface */
-      struct sockaddr_dl dl;
-      const char *iname;
-      int ilen;
-
-      iname = Index2Nam(bundle->ifp.Index);
-      ilen = strlen(iname);
-      dl.sdl_len = sizeof dl - sizeof dl.sdl_data + ilen;
-      dl.sdl_family = AF_LINK;
-      dl.sdl_index = bundle->ifp.Index;
-      dl.sdl_type = 0;
-      dl.sdl_nlen = ilen;
-      dl.sdl_alen = 0;
-      dl.sdl_slen = 0;
-      strncpy(dl.sdl_data, iname, sizeof dl.sdl_data);
-      memcpy(cp, &dl, dl.sdl_len);
-      cp += dl.sdl_len;
-      rtmes.m_rtm.rtm_addrs |= RTA_GATEWAY;
+      log_Printf(LogERROR, "bundle_SetRoute: Cannot add a route with"
+                 " destination 0.0.0.0\n");
+      close(s);
+      return result;
     } else {
       rtdata.sin_addr = gateway;
       memcpy(cp, &rtdata, rtdata.sin_len);
@@ -1241,7 +1191,7 @@ bundle_ShowStatus(struct cmdargs const *arg)
   prompt_Printf(arg->prompt, "Phase %s\n", bundle_PhaseName(arg->bundle));
   prompt_Printf(arg->prompt, " Device:        %s\n", arg->bundle->dev.Name);
   prompt_Printf(arg->prompt, " Interface:     %s @ %lubps\n",
-                arg->bundle->ifp.Name, arg->bundle->ifp.Speed);
+                arg->bundle->iface->name, arg->bundle->ifSpeed);
 
   prompt_Printf(arg->prompt, "\nDefaults:\n");
   prompt_Printf(arg->prompt, " Label:         %s\n", arg->bundle->cfg.label);
@@ -1294,6 +1244,8 @@ bundle_ShowStatus(struct cmdargs const *arg)
                 optval(arg->bundle, OPT_THROUGHPUT));
   prompt_Printf(arg->prompt, " Utmp Logging:  %s\n",
                 optval(arg->bundle, OPT_UTMP));
+  prompt_Printf(arg->prompt, " Iface-Alias:   %s\n",
+                optval(arg->bundle, OPT_IFACEALIAS));
 
   return 0;
 }
@@ -1636,11 +1588,6 @@ bundle_SetMode(struct bundle *bundle, struct datalink *dl, int mode)
   /* Regenerate phys_type and adjust autoload & idle timers */
   bundle_LinksRemoved(bundle);
 
-  if (omode == PHYS_AUTO && !(bundle->phys_type.all & PHYS_AUTO) &&
-      bundle->phase != PHASE_NETWORK)
-    /* No auto links left */
-    ipcp_CleanInterface(&bundle->ncp.ipcp);
-
   return 1;
 }