ipv6cp: Fix enforcing local and peer non-random IPv6 interface identifiers (#283)

[ppp.git] / pppd / ipv6cp.c

diff --git a/pppd/ipv6cp.c b/pppd/ipv6cp.c
index fef147adf260b4eac6e1185aaafe359c1cf0fcf3..ef03e1015503220db596ef2e3045ae5eb65af0df 100644 (file)
--- a/pppd/ipv6cp.c
+++ b/pppd/ipv6cp.c
@@ -720,7 +720,9 @@ ipv6cp_nakci(fsm *f, u_char *p, int len, int treat_as_reject)
     NAKCIIFACEID(CI_IFACEID, neg_ifaceid,
                 if (treat_as_reject) {
                     try.neg_ifaceid = 0;
-                } else if (go->accept_local) {
+                } else if (go->accept_local && !eui64_iszero(ifaceid) && !eui64_equals(ifaceid, go->hisid)) {
+                    try.ourid = ifaceid;
+                } else if (eui64_iszero(ifaceid) && !go->opt_local) {
                     while (eui64_iszero(ifaceid) || 
                            eui64_equals(ifaceid, go->hisid)) /* bad luck */
                         eui64_magic(ifaceid);
@@ -772,11 +774,15 @@ ipv6cp_nakci(fsm *f, u_char *p, int len, int treat_as_reject)
                goto bad;
            try.neg_ifaceid = 1;
            eui64_get(ifaceid, p);
-           if (go->accept_local) {
+           if (go->accept_local && !eui64_iszero(ifaceid) && !eui64_equals(ifaceid, go->hisid)) {
+               try.ourid = ifaceid;
+           } else if (eui64_iszero(ifaceid) && !go->opt_local) {
                while (eui64_iszero(ifaceid) || 
                       eui64_equals(ifaceid, go->hisid)) /* bad luck */
                    eui64_magic(ifaceid);
                try.ourid = ifaceid;
+           } else {
+               try.neg_ifaceid = 0;
            }
            no.neg_ifaceid = 1;
            break;
@@ -955,9 +961,17 @@ ipv6cp_reqci(fsm *f, u_char *inp, int *len, int reject_if_disagree)
                orc = CONFNAK;
                if (eui64_iszero(go->hisid))    /* first time, try option */
                    ifaceid = wo->hisid;
-               while (eui64_iszero(ifaceid) || 
-                      eui64_equals(ifaceid, go->ourid)) /* bad luck */
-                   eui64_magic(ifaceid);
+               if (eui64_equals(ifaceid, go->ourid)) /* bad luck */
+                   eui64_zero(ifaceid);
+               if (eui64_iszero(ifaceid)) {
+                   if (wo->opt_remote)
+                       ifaceid = wo->hisid;
+                   else {
+                       while (eui64_iszero(ifaceid) ||
+                              eui64_equals(ifaceid, go->ourid)) /* bad luck */
+                           eui64_magic(ifaceid);
+                   }
+               }
                go->hisid = ifaceid;
                DECPTR(sizeof(ifaceid), p);
                eui64_put(ifaceid, p);