pppd: Fix enforcing peer IP address (#235)

[ppp.git] / pppd / ipcp.c

diff --git a/pppd/ipcp.c b/pppd/ipcp.c
index d95b69b910f2dd41277e16d7445f841d8b50f3c1..fcf17b1e7472dcb4bc8c07c0b73827daf1e92c5f 100644 (file)
--- a/pppd/ipcp.c
+++ b/pppd/ipcp.c
@@ -1760,6 +1760,12 @@ ipcp_up(fsm *f)
     /*
      * We must have a non-zero IP address for both ends of the link.
      */
+
+    if (wo->hisaddr && !wo->accept_remote && (!(ho->neg_addr || ho->old_addrs) || ho->hisaddr != wo->hisaddr)) {
+       error("Peer refused to agree to his IP address");
+       ipcp_close(f->unit, "Refused his IP address");
+       return;
+    }
     if (!ho->neg_addr && !ho->old_addrs)
        ho->hisaddr = wo->hisaddr;
 
@@ -1823,9 +1829,10 @@ ipcp_up(fsm *f)
                wo->ouraddr = go->ouraddr;
            } else
                script_unsetenv("OLDIPLOCAL");
-           if (ho->hisaddr != wo->hisaddr && wo->hisaddr != 0) {
+           if (ho->hisaddr != wo->hisaddr) {
                warn("Remote IP address changed to %I", ho->hisaddr);
-               script_setenv("OLDIPREMOTE", ip_ntoa(wo->hisaddr), 0);
+               if (wo->hisaddr != 0)
+                   script_setenv("OLDIPREMOTE", ip_ntoa(wo->hisaddr), 0);
                wo->hisaddr = ho->hisaddr;
            } else
                script_unsetenv("OLDIPREMOTE");