o Add ipv6 support, abstracting most NCP addresses into opaque

  structures (well, they're treated as opaque).

  It's now possible to manage IPv6 interface addresses and routing
  table entries and to filter IPV6 traffic whether encapsulated or
  not.

  IPV6CP support is crude for now, and hasn't been tested against
  any other implementations.

  RADIUS and IPv6 are independent of eachother for now.

  ppp.linkup/ppp.linkdown aren't currently used by IPV6CP

o Understand all protocols(5) in filter rules rather than only a select
  few.

o Allow a mask specification for the ``delete'' command.  It's now
  possible to specifically delete one of two conflicting routes.

o When creating and deleting proxy arp entries, do it for all IPv4
  interface addresses rather than doing it just for the ``current''
  peer address.

o When iface-alias isn't in effect, don't blow away manually (via ``iface
  add'') added interface addresses.

o When listening on a tcp server (diagnostic) socket, bind so that a
  tcp46 socket is created -- allowing both IPv4 and IPv6 connections.

o When displaying ICMP traffic, don't display the icmp type twice.
  When display traffic, display at least some information about unrecognised
  traffic.

o Bump version

Inspired after filtering work by: Makoto MATSUSHITA <matusita@jp.FreeBSD.org>

1 files changed, 601 insertions, 0 deletions

diff --git a/usr.sbin/ppp/ipv6cp.c b/usr.sbin/ppp/ipv6cp.c
new file mode 100644
index 0000000..eb76465
--- /dev/null
+++ b/usr.sbin/ppp/ipv6cp.c
@@ -0,0 +1,601 @@
+/*-
+ * Copyright (c) 2001 Brian Somers <brian@Awfulhak.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <sys/param.h>
+#include <netinet/in_systm.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <sys/socket.h>
+#include <net/route.h>
+#include <net/if.h>
+#include <sys/un.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <termios.h>
+
+#include "layer.h"
+#include "defs.h"
+#include "mbuf.h"
+#include "timer.h"
+#include "fsm.h"
+#include "iplist.h"
+#include "throughput.h"
+#include "slcompress.h"
+#include "lqr.h"
+#include "hdlc.h"
+#include "lcp.h"
+#include "ncpaddr.h"
+#include "ip.h"
+#include "ipcp.h"
+#include "ipv6cp.h"
+#include "filter.h"
+#include "descriptor.h"
+#include "ccp.h"
+#include "link.h"
+#include "mp.h"
+#ifndef NORADIUS
+#include "radius.h"
+#endif
+#include "ncp.h"
+#include "bundle.h"
+#include "route.h"
+#include "iface.h"
+#include "log.h"
+#include "proto.h"
+#include "command.h"
+#include "prompt.h"
+#include "async.h"
+#include "physical.h"
+
+
+#ifndef NOINET6
+static int ipv6cp_LayerUp(struct fsm *);
+static void ipv6cp_LayerDown(struct fsm *);
+static void ipv6cp_LayerStart(struct fsm *);
+static void ipv6cp_LayerFinish(struct fsm *);
+static void ipv6cp_InitRestartCounter(struct fsm *, int);
+static void ipv6cp_SendConfigReq(struct fsm *);
+static void ipv6cp_SentTerminateReq(struct fsm *);
+static void ipv6cp_SendTerminateAck(struct fsm *, u_char);
+static void ipv6cp_DecodeConfig(struct fsm *, u_char *, int, int,
+                                struct fsm_decode *);
+
+static struct fsm_callbacks ipv6cp_Callbacks = {
+  ipv6cp_LayerUp,
+  ipv6cp_LayerDown,
+  ipv6cp_LayerStart,
+  ipv6cp_LayerFinish,
+  ipv6cp_InitRestartCounter,
+  ipv6cp_SendConfigReq,
+  ipv6cp_SentTerminateReq,
+  ipv6cp_SendTerminateAck,
+  ipv6cp_DecodeConfig,
+  fsm_NullRecvResetReq,
+  fsm_NullRecvResetAck
+};
+
+static u_int32_t
+GenerateToken(void)
+{
+  /* Generate random number which will be used as negotiation token */
+  randinit();
+
+  return random() + 1;
+}
+
+static int
+ipcp_SetIPv6address(struct ipv6cp *ipv6cp, u_int32_t mytok, u_int32_t histok)
+{
+  struct bundle *bundle = ipv6cp->fsm.bundle;
+  struct in6_addr myaddr, hisaddr;
+  struct ncprange myrange, dst;
+
+  memset(&myaddr, '\0', sizeof myaddr);
+  memset(&hisaddr, '\0', sizeof hisaddr);
+
+  myaddr.s6_addr[0] = 0xfe;
+  myaddr.s6_addr[1] = 0x80;
+  *(u_int32_t *)(myaddr.s6_addr + 12) = htonl(mytok);
+
+  hisaddr.s6_addr[0] = 0xfe;
+  hisaddr.s6_addr[1] = 0x80;
+  *(u_int32_t *)(hisaddr.s6_addr + 12) = htonl(histok);
+
+  ncpaddr_setip6(&ipv6cp->myaddr, &myaddr);
+  ncpaddr_setip6(&ipv6cp->hisaddr, &hisaddr);
+  ncprange_sethost(&myrange, &ipv6cp->myaddr);
+
+  if (!iface_Add(bundle->iface, &bundle->ncp, &myrange, &ipv6cp->hisaddr,
+                 IFACE_ADD_FIRST|IFACE_FORCE_ADD|IFACE_SYSTEM))
+    return 0;
+
+  if (!Enabled(bundle, OPT_IFACEALIAS))
+    iface_Clear(bundle->iface, &bundle->ncp, AF_INET6,
+                IFACE_CLEAR_ALIASES|IFACE_SYSTEM);
+
+  if (bundle->ncp.cfg.sendpipe > 0 || bundle->ncp.cfg.recvpipe > 0) {
+    ncprange_sethost(&dst, &ipv6cp->hisaddr);
+    rt_Update(bundle, &dst);
+  }
+
+  if (Enabled(bundle, OPT_SROUTES))
+    route_Change(bundle, bundle->ncp.route, &ipv6cp->myaddr, &ipv6cp->hisaddr);
+
+#ifndef NORADIUS
+  if (bundle->radius.valid)
+    route_Change(bundle, bundle->radius.routes, &ipv6cp->myaddr,
+                 &ipv6cp->hisaddr);
+#endif
+
+  return 1;	/* Ok */
+}
+
+void
+ipv6cp_Init(struct ipv6cp *ipv6cp, struct bundle *bundle, struct link *l,
+                 const struct fsm_parent *parent)
+{
+  static const char * const timer_names[] =
+    {"IPV6CP restart", "IPV6CP openmode", "IPV6CP stopped"};
+  int n;
+
+  fsm_Init(&ipv6cp->fsm, "IPV6CP", PROTO_IPV6CP, 1, IPV6CP_MAXCODE, LogIPV6CP,
+           bundle, l, parent, &ipv6cp_Callbacks, timer_names);
+
+  ipv6cp->cfg.fsm.timeout = DEF_FSMRETRY;
+  ipv6cp->cfg.fsm.maxreq = DEF_FSMTRIES;
+  ipv6cp->cfg.fsm.maxtrm = DEF_FSMTRIES;
+
+  ipv6cp->my_token = GenerateToken();
+  while ((ipv6cp->peer_token = GenerateToken()) == ipv6cp->my_token)
+    ;
+
+  n = 100;
+  while (n &&
+         !ipcp_SetIPv6address(ipv6cp, ipv6cp->my_token, ipv6cp->peer_token))
+    while (n && (ipv6cp->my_token = GenerateToken()) == ipv6cp->peer_token)
+      n--;
+
+  throughput_init(&ipv6cp->throughput, SAMPLE_PERIOD);
+  memset(ipv6cp->Queue, '\0', sizeof ipv6cp->Queue);
+  ipv6cp_Setup(ipv6cp);
+}
+
+void
+ipv6cp_Destroy(struct ipv6cp *ipv6cp)
+{
+  throughput_destroy(&ipv6cp->throughput);
+}
+
+void
+ipv6cp_Setup(struct ipv6cp *ipv6cp)
+{
+  ncpaddr_init(&ipv6cp->myaddr);
+  ncpaddr_init(&ipv6cp->hisaddr);
+
+  ipv6cp->his_reject = 0;
+  ipv6cp->my_reject = 0;
+}
+
+void
+ipv6cp_SetLink(struct ipv6cp *ipv6cp, struct link *l)
+{
+  ipv6cp->fsm.link = l;
+}
+
+int
+ipv6cp_Show(struct cmdargs const *arg)
+{
+  struct ipv6cp *ipv6cp = &arg->bundle->ncp.ipv6cp;
+
+  prompt_Printf(arg->prompt, "%s [%s]\n", ipv6cp->fsm.name,
+                State2Nam(ipv6cp->fsm.state));
+  if (ipv6cp->fsm.state == ST_OPENED) {
+    prompt_Printf(arg->prompt, " His side:        %s\n",
+	          ncpaddr_ntoa(&ipv6cp->hisaddr));
+    prompt_Printf(arg->prompt, " My side:         %s\n",
+	          ncpaddr_ntoa(&ipv6cp->myaddr));
+    prompt_Printf(arg->prompt, " Queued packets:  %lu\n",
+                  (unsigned long)ipv6cp_QueueLen(ipv6cp));
+  }
+
+  prompt_Printf(arg->prompt, "\nDefaults:\n");
+  prompt_Printf(arg->prompt, "  FSM retry = %us, max %u Config"
+                " REQ%s, %u Term REQ%s\n\n", ipv6cp->cfg.fsm.timeout,
+                ipv6cp->cfg.fsm.maxreq, ipv6cp->cfg.fsm.maxreq == 1 ? "" : "s",
+                ipv6cp->cfg.fsm.maxtrm, ipv6cp->cfg.fsm.maxtrm == 1 ? "" : "s");
+
+  throughput_disp(&ipv6cp->throughput, arg->prompt);
+
+  return 0;
+}
+
+struct mbuf *
+ipv6cp_Input(struct bundle *bundle, struct link *l, struct mbuf *bp)
+{
+  /* Got PROTO_IPV6CP from link */
+  m_settype(bp, MB_IPV6CPIN);
+  if (bundle_Phase(bundle) == PHASE_NETWORK)
+    fsm_Input(&bundle->ncp.ipv6cp.fsm, bp);
+  else {
+    if (bundle_Phase(bundle) < PHASE_NETWORK)
+      log_Printf(LogIPV6CP, "%s: Error: Unexpected IPV6CP in phase %s"
+                 " (ignored)\n", l->name, bundle_PhaseName(bundle));
+    m_freem(bp);
+  }
+  return NULL;
+}
+
+void
+ipv6cp_AddInOctets(struct ipv6cp *ipv6cp, int n)
+{
+  throughput_addin(&ipv6cp->throughput, n);
+}
+
+void
+ipv6cp_AddOutOctets(struct ipv6cp *ipv6cp, int n)
+{
+  throughput_addout(&ipv6cp->throughput, n);
+}
+
+void
+ipv6cp_IfaceAddrAdded(struct ipv6cp *ipv6cp, const struct iface_addr *addr)
+{
+}
+
+void
+ipv6cp_IfaceAddrDeleted(struct ipv6cp *ipv6cp, const struct iface_addr *addr)
+{
+}
+
+int
+ipv6cp_InterfaceUp(struct ipv6cp *ipv6cp)
+{
+  if (!ipcp_SetIPv6address(ipv6cp, ipv6cp->my_token, ipv6cp->peer_token)) {
+    log_Printf(LogERROR, "ipv6cp_InterfaceUp: unable to set ipv6 address\n");
+    return 0;
+  }
+
+  if (!iface_SetFlags(ipv6cp->fsm.bundle->iface->name, IFF_UP)) {
+    log_Printf(LogERROR, "ipv6cp_InterfaceUp: Can't set the IFF_UP"
+               " flag on %s\n", ipv6cp->fsm.bundle->iface->name);
+    return 0;
+  }
+
+  return 1;
+}
+
+size_t
+ipv6cp_QueueLen(struct ipv6cp *ipv6cp)
+{
+  struct mqueue *q;
+  size_t result;
+
+  result = 0;
+  for (q = ipv6cp->Queue; q < ipv6cp->Queue + IPV6CP_QUEUES(ipv6cp); q++)
+    result += q->len;
+
+  return result;
+}
+
+int
+ipv6cp_PushPacket(struct ipv6cp *ipv6cp, struct link *l)
+{
+  struct bundle *bundle = ipv6cp->fsm.bundle;
+  struct mqueue *queue;
+  struct mbuf *bp;
+  int m_len;
+  u_int32_t secs = 0;
+  unsigned alivesecs = 0;
+
+  if (ipv6cp->fsm.state != ST_OPENED)
+    return 0;
+
+  /*
+   * If ccp is not open but is required, do nothing.
+   */
+  if (l->ccp.fsm.state != ST_OPENED && ccp_Required(&l->ccp)) {
+    log_Printf(LogPHASE, "%s: Not transmitting... waiting for CCP\n", l->name);
+    return 0;
+  }
+
+  queue = ipv6cp->Queue + IPV6CP_QUEUES(ipv6cp) - 1;
+  do {
+    if (queue->top) {
+      bp = m_dequeue(queue);
+      bp = mbuf_Read(bp, &secs, sizeof secs);
+      bp = m_pullup(bp);
+      m_len = m_length(bp);
+      if (!FilterCheck(MBUF_CTOP(bp), AF_INET6, &bundle->filter.alive,
+                       &alivesecs)) {
+        if (secs == 0)
+          secs = alivesecs;
+        bundle_StartIdleTimer(bundle, secs);
+      }
+      link_PushPacket(l, bp, bundle, 0, PROTO_IPV6);
+      ipv6cp_AddOutOctets(ipv6cp, m_len);
+      return 1;
+    }
+  } while (queue-- != ipv6cp->Queue);
+
+  return 0;
+}
+
+static int
+ipv6cp_LayerUp(struct fsm *fp)
+{
+  /* We're now up */
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+  char tbuff[40];
+
+  log_Printf(LogIPV6CP, "%s: LayerUp.\n", fp->link->name);
+  if (!ipv6cp_InterfaceUp(ipv6cp))
+    return 0;
+
+  snprintf(tbuff, sizeof tbuff, "%s", ncpaddr_ntoa(&ipv6cp->myaddr));
+  log_Printf(LogIPV6CP, "myaddr %s hisaddr = %s\n",
+             tbuff, ncpaddr_ntoa(&ipv6cp->hisaddr));
+
+  /* XXX: Call radius_Account() and system_Select() */
+
+  fp->more.reqs = fp->more.naks = fp->more.rejs = ipv6cp->cfg.fsm.maxreq * 3;
+  log_DisplayPrompts();
+
+  return 1;
+}
+
+static void
+ipv6cp_LayerDown(struct fsm *fp)
+{
+  /* About to come down */
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+  static int recursing;
+  char addr[40];
+
+  if (!recursing++) {
+    snprintf(addr, sizeof addr, "%s", ncpaddr_ntoa(&ipv6cp->myaddr));
+    log_Printf(LogIPV6CP, "%s: LayerDown: %s\n", fp->link->name, addr);
+
+    /* XXX: Call radius_Account() and system_Select() */
+
+    ipv6cp_Setup(ipv6cp);
+  }
+  recursing--;
+}
+
+static void
+ipv6cp_LayerStart(struct fsm *fp)
+{
+  /* We're about to start up ! */
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+
+  log_Printf(LogIPV6CP, "%s: LayerStart.\n", fp->link->name);
+  throughput_start(&ipv6cp->throughput, "IPV6CP throughput",
+                   Enabled(fp->bundle, OPT_THROUGHPUT));
+  fp->more.reqs = fp->more.naks = fp->more.rejs = ipv6cp->cfg.fsm.maxreq * 3;
+  ipv6cp->peer_tokenreq = 0;
+}
+
+static void
+ipv6cp_LayerFinish(struct fsm *fp)
+{
+  /* We're now down */
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+
+  log_Printf(LogIPV6CP, "%s: LayerFinish.\n", fp->link->name);
+  throughput_stop(&ipv6cp->throughput);
+  throughput_log(&ipv6cp->throughput, LogIPV6CP, NULL);
+}
+
+static void
+ipv6cp_InitRestartCounter(struct fsm *fp, int what)
+{
+  /* Set fsm timer load */
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+
+  fp->FsmTimer.load = ipv6cp->cfg.fsm.timeout * SECTICKS;
+  switch (what) {
+    case FSM_REQ_TIMER:
+      fp->restart = ipv6cp->cfg.fsm.maxreq;
+      break;
+    case FSM_TRM_TIMER:
+      fp->restart = ipv6cp->cfg.fsm.maxtrm;
+      break;
+    default:
+      fp->restart = 1;
+      break;
+  }
+}
+
+static void
+ipv6cp_SendConfigReq(struct fsm *fp)
+{
+  /* Send config REQ please */
+  struct physical *p = link2physical(fp->link);
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+  u_char buff[6];
+  struct lcp_opt *o;
+
+  o = (struct lcp_opt *)buff;
+
+  if ((p && !physical_IsSync(p)) || !REJECTED(ipv6cp, TY_TOKEN)) {
+    memcpy(o->data, &ipv6cp->my_token, 4);
+    INC_LCP_OPT(TY_TOKEN, 6, o);
+  }
+
+  fsm_Output(fp, CODE_CONFIGREQ, fp->reqid, buff, (u_char *)o - buff,
+             MB_IPV6CPOUT);
+}
+
+static void
+ipv6cp_SentTerminateReq(struct fsm *fp)
+{
+  /* Term REQ just sent by FSM */
+}
+
+static void
+ipv6cp_SendTerminateAck(struct fsm *fp, u_char id)
+{
+  /* Send Term ACK please */
+  fsm_Output(fp, CODE_TERMACK, id, NULL, 0, MB_IPV6CPOUT);
+}
+
+static const char *
+protoname(int proto)
+{
+  static const char *cftypes[] = { "TOKEN", "COMPPROTO" };
+
+  if (proto > 0 && proto <= sizeof cftypes / sizeof *cftypes)
+    return cftypes[proto - 1];
+
+  return NumStr(proto, NULL, 0);
+}
+
+static void
+ipv6cp_ValidateToken(struct ipv6cp *ipv6cp, u_int32_t token,
+                     struct fsm_decode *dec)
+{
+  if (token != 0 && token != ipv6cp->my_token)
+    ipv6cp->peer_token = token;
+
+  if (token == ipv6cp->peer_token) {
+    *dec->ackend++ = TY_TOKEN;
+    *dec->ackend++ = 6;
+    memcpy(dec->ackend, &ipv6cp->peer_token, 4);
+    dec->ackend += 4;
+  } else {
+    *dec->nakend++ = TY_TOKEN;
+    *dec->nakend++ = 6;
+    memcpy(dec->nakend, &ipv6cp->peer_token, 4);
+    dec->nakend += 4;
+  }
+}
+
+static void
+ipv6cp_DecodeConfig(struct fsm *fp, u_char *cp, int plen, int mode_type,
+                    struct fsm_decode *dec)
+{
+  /* Deal with incoming PROTO_IPV6CP */
+  struct ipv6cp *ipv6cp = fsm2ipv6cp(fp);
+  int type, length, n;
+  char tbuff[100];
+  u_int32_t token;
+
+  while (plen >= sizeof(struct fsmconfig)) {
+    type = *cp;
+    length = cp[1];
+
+    if (length == 0) {
+      log_Printf(LogIPV6CP, "%s: IPV6CP size zero\n", fp->link->name);
+      break;
+    }
+
+    snprintf(tbuff, sizeof tbuff, " %s[%d] ", protoname(type), length);
+
+    switch (type) {
+    case TY_TOKEN:
+      memcpy(&token, cp + 2, 4);
+      log_Printf(LogIPV6CP, "%s 0x%08lx\n", tbuff, (unsigned long)token);
+
+      switch (mode_type) {
+      case MODE_REQ:
+        ipv6cp->peer_tokenreq = 1;
+        ipv6cp_ValidateToken(ipv6cp, token, dec);
+	break;
+
+      case MODE_NAK:
+        if (token == 0) {
+	  log_Printf(log_IsKept(LogIPV6CP) ? LogIPV6CP : LogPHASE,
+                     "0x00000000: Unacceptable token!\n");
+          fsm_Close(&ipv6cp->fsm);
+        } else if (token == ipv6cp->peer_token)
+	  log_Printf(log_IsKept(LogIPV6CP) ? LogIPV6CP : LogPHASE,
+                    "0x08lx: Unacceptable token!\n", (unsigned long)token);
+        else if (token != ipv6cp->my_token) {
+          n = 100;
+          while (n && !ipcp_SetIPv6address(ipv6cp, token, ipv6cp->peer_token))
+            while (n && (token = GenerateToken()) == ipv6cp->peer_token)
+              n--;
+
+          if (n == 0) {
+	    log_Printf(log_IsKept(LogIPV6CP) ? LogIPV6CP : LogPHASE,
+                       "0x00000000: Unacceptable token!\n");
+            fsm_Close(&ipv6cp->fsm);
+          } else {
+	    log_Printf(LogIPV6CP, "%s changing token: 0x%08lx --> 0x%08lx\n",
+                       tbuff, (unsigned long)ipv6cp->my_token,
+                       (unsigned long)token);
+            ipv6cp->my_token = token;
+            bundle_AdjustFilters(fp->bundle, &ipv6cp->myaddr, NULL);
+          }
+        }
+	break;
+
+      case MODE_REJ:
+	ipv6cp->his_reject |= (1 << type);
+	break;
+      }
+      break;
+
+    default:
+      if (mode_type != MODE_NOP) {
+        ipv6cp->my_reject |= (1 << type);
+        memcpy(dec->rejend, cp, length);
+        dec->rejend += length;
+      }
+      break;
+    }
+    plen -= length;
+    cp += length;
+  }
+
+  if (mode_type != MODE_NOP) {
+    if (mode_type == MODE_REQ && !ipv6cp->peer_tokenreq) {
+      if (dec->rejend == dec->rej && dec->nakend == dec->nak) {
+        /*
+         * Pretend the peer has requested a TOKEN.
+         * We do this to ensure that we only send one NAK if the only
+         * reason for the NAK is because the peer isn't sending a
+         * TY_TOKEN REQ.  This stops us from repeatedly trying to tell
+         * the peer that we have to have an IP address on their end.
+         */
+        ipv6cp->peer_tokenreq = 1;
+      }
+      ipv6cp_ValidateToken(ipv6cp, 0, dec);
+    }
+    if (dec->rejend != dec->rej) {
+      /* rejects are preferred */
+      dec->ackend = dec->ack;
+      dec->nakend = dec->nak;
+    } else if (dec->nakend != dec->nak)
+      /* then NAKs */
+      dec->ackend = dec->ack;
+  }
+}
+#endif