pppd: Fix SIGSEGV in EAP-TLS code when TLS verify method is not specified

[ppp.git] / pppd / ipcp.c

diff --git a/pppd/ipcp.c b/pppd/ipcp.c
index 7357ac8ea546323f3ba178db99f0e77639beef3f..d17dbd28a04d225cd5d5d43dc40547c3e358eb3e 100644 (file)
--- a/pppd/ipcp.c
+++ b/pppd/ipcp.c
@@ -196,6 +196,15 @@ static option_t ipcp_option_list[] = {
       "disable defaultroute option", OPT_ALIAS | OPT_A2CLR,
       &ipcp_wantoptions[0].default_route },
 
+#ifdef __linux__
+    { "replacedefaultroute", o_bool,
+                               &ipcp_wantoptions[0].replace_default_route,
+      "Replace default route", OPT_PRIV | 1
+    },
+    { "noreplacedefaultroute", o_bool,
+                               &ipcp_wantoptions[0].replace_default_route,
+      "Do not replace default route", 0 },
+#endif
     { "proxyarp", o_bool, &ipcp_wantoptions[0].proxy_arp,
       "Add proxy ARP entry", OPT_ENABLE|1, &ipcp_allowoptions[0].proxy_arp },
     { "noproxyarp", o_bool, &ipcp_allowoptions[0].proxy_arp,
@@ -269,7 +278,7 @@ struct protent ipcp_protent = {
     ip_active_pkt
 };
 
-static void ipcp_clear_addrs (int, u_int32_t, u_int32_t);
+static void ipcp_clear_addrs (int, u_int32_t, u_int32_t, bool);
 static void ipcp_script (char *, int); /* Run an up/down script */
 static void ipcp_script_done (void *);
 
@@ -669,8 +678,9 @@ ipcp_resetci(fsm *f)
     ipcp_options *go = &ipcp_gotoptions[f->unit];
     ipcp_options *ao = &ipcp_allowoptions[f->unit];
 
-    wo->req_addr = (wo->neg_addr || wo->old_addrs) &&
-       (ao->neg_addr || ao->old_addrs);
+    wo->req_addr = ((wo->neg_addr || wo->old_addrs) &&
+       (ao->neg_addr || ao->old_addrs)) ||
+       (wo->hisaddr && !wo->accept_remote);
     if (wo->ouraddr == 0)
        wo->accept_local = 1;
     if (wo->hisaddr == 0)
@@ -985,6 +995,7 @@ bad:
 static int
 ipcp_nakci(fsm *f, u_char *p, int len, int treat_as_reject)
 {
+    ipcp_options *wo = &ipcp_wantoptions[f->unit];
     ipcp_options *go = &ipcp_gotoptions[f->unit];
     u_char cimaxslotindex, cicflag;
     u_char citype, cilen, *next;
@@ -1160,7 +1171,7 @@ ipcp_nakci(fsm *f, u_char *p, int len, int treat_as_reject)
            GETLONG(l, p);
            ciaddr1 = htonl(l);
            if (ciaddr1 && go->accept_local)
-               try.ouraddr = ciaddr1;
+               try.ouraddr = wo->old_addrs ? ciaddr1 : 0;
            GETLONG(l, p);
            ciaddr2 = htonl(l);
            if (ciaddr2 && go->accept_remote)
@@ -1175,7 +1186,7 @@ ipcp_nakci(fsm *f, u_char *p, int len, int treat_as_reject)
            ciaddr1 = htonl(l);
            if (ciaddr1 && go->accept_local)
                try.ouraddr = ciaddr1;
-           if (try.ouraddr != 0)
+           if (try.ouraddr != 0 && wo->neg_addr)
                try.neg_addr = 1;
            no.neg_addr = 1;
            break;
@@ -1461,7 +1472,7 @@ ipcp_reqci(fsm *f, u_char *inp,   int *len, int reject_if_disagree)
            if (ciaddr2 != wo->ouraddr) {
                if (ciaddr2 == 0 || !wo->accept_local) {
                    orc = CONFNAK;
-                   if (!reject_if_disagree) {
+                   if (!reject_if_disagree && wo->old_addrs) {
                        DECPTR(sizeof(u_int32_t), p);
                        tl = ntohl(wo->ouraddr);
                        PUTLONG(tl, p);
@@ -1638,7 +1649,8 @@ endswitch:
      * option safely.
      */
     if (rc != CONFREJ && !ho->neg_addr && !ho->old_addrs &&
-       wo->req_addr && !reject_if_disagree && !noremoteip) {
+       wo->req_addr && !reject_if_disagree &&
+       ((wo->hisaddr && !wo->accept_remote) || !noremoteip)) {
        if (rc == CONFACK) {
            rc = CONFNAK;
            ucp = inp;                  /* reset pointer */
@@ -1716,7 +1728,8 @@ ip_demand_conf(int u)
     if (!sifnpmode(u, PPP_IP, NPMODE_QUEUE))
        return 0;
     if (wo->default_route)
-       if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr))
+       if (sifdefaultroute(u, wo->ouraddr, wo->hisaddr,
+                                           wo->replace_default_route))
            default_route_set[u] = 1;
     if (wo->proxy_arp)
        if (sifproxyarp(u, wo->hisaddr))
@@ -1749,6 +1762,12 @@ 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;
 
@@ -1804,16 +1823,18 @@ ipcp_up(fsm *f)
      */
     if (demand) {
        if (go->ouraddr != wo->ouraddr || ho->hisaddr != wo->hisaddr) {
-           ipcp_clear_addrs(f->unit, wo->ouraddr, wo->hisaddr);
+           ipcp_clear_addrs(f->unit, wo->ouraddr, wo->hisaddr,
+                                     wo->replace_default_route);
            if (go->ouraddr != wo->ouraddr) {
                warn("Local IP address changed to %I", go->ouraddr);
                script_setenv("OLDIPLOCAL", ip_ntoa(wo->ouraddr), 0);
                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");
@@ -1829,7 +1850,8 @@ ipcp_up(fsm *f)
 
            /* assign a default route through the interface if required */
            if (ipcp_wantoptions[f->unit].default_route) 
-               if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr))
+               if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr,
+                                            wo->replace_default_route))
                    default_route_set[f->unit] = 1;
 
            /* Make a proxy ARP entry if requested. */
@@ -1888,7 +1910,8 @@ ipcp_up(fsm *f)
 
        /* assign a default route through the interface if required */
        if (ipcp_wantoptions[f->unit].default_route) 
-           if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr))
+           if (sifdefaultroute(f->unit, go->ouraddr, ho->hisaddr,
+                                        wo->replace_default_route))
                default_route_set[f->unit] = 1;
 
        /* Make a proxy ARP entry if requested. */
@@ -1922,7 +1945,7 @@ ipcp_up(fsm *f)
      */
     if (ipcp_script_state == s_down && ipcp_script_pid == 0) {
        ipcp_script_state = s_up;
-       ipcp_script(_PATH_IPUP, 0);
+       ipcp_script(path_ipup, 0);
     }
 }
 
@@ -1965,13 +1988,13 @@ ipcp_down(fsm *f)
        sifnpmode(f->unit, PPP_IP, NPMODE_DROP);
        sifdown(f->unit);
        ipcp_clear_addrs(f->unit, ipcp_gotoptions[f->unit].ouraddr,
-                        ipcp_hisoptions[f->unit].hisaddr);
+                        ipcp_hisoptions[f->unit].hisaddr, 0);
     }
 
     /* Execute the ip-down script */
     if (ipcp_script_state == s_up && ipcp_script_pid == 0) {
        ipcp_script_state = s_down;
-       ipcp_script(_PATH_IPDOWN, 0);
+       ipcp_script(path_ipdown, 0);
     }
 }
 
@@ -1981,13 +2004,21 @@ ipcp_down(fsm *f)
  * proxy arp entries, etc.
  */
 static void
-ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr)
+ipcp_clear_addrs(int unit, u_int32_t ouraddr, u_int32_t hisaddr, bool replacedefaultroute)
 {
     if (proxy_arp_set[unit]) {
        cifproxyarp(unit, hisaddr);
        proxy_arp_set[unit] = 0;
     }
-    if (default_route_set[unit]) {
+    /* If replacedefaultroute, sifdefaultroute will be called soon
+     * with replacedefaultroute set and that will overwrite the current
+     * default route. This is the case only when doing demand, otherwise
+     * during demand, this cifdefaultroute would restore the old default
+     * route which is not what we want in this case. In the non-demand
+     * case, we'll delete the default route and restore the old if there
+     * is one saved by an sifdefaultroute with replacedefaultroute.
+     */
+    if (!replacedefaultroute && default_route_set[unit]) {
        cifdefaultroute(unit, ouraddr, hisaddr);
        default_route_set[unit] = 0;
     }
@@ -2020,13 +2051,13 @@ ipcp_script_done(void *arg)
     case s_up:
        if (ipcp_fsm[0].state != OPENED) {
            ipcp_script_state = s_down;
-           ipcp_script(_PATH_IPDOWN, 0);
+           ipcp_script(path_ipdown, 0);
        }
        break;
     case s_down:
        if (ipcp_fsm[0].state == OPENED) {
            ipcp_script_state = s_up;
-           ipcp_script(_PATH_IPUP, 0);
+           ipcp_script(path_ipup, 0);
        }
        break;
     }