PPP, IPv4 support is now optional

New compile time option: PPP_IPV4_SUPPORT

PPP IPv4 support can now be compiled out.

src/include/lwip/opt.h

@@ -1933,6 +1933,13 @@
 #define PRINTPKT_SUPPORT                0
 #endif
 
+/**
+ * PPP_IPV4_SUPPORT==1: Enable PPP IPv4 support
+ */
+#ifndef PPP_IPV4_SUPPORT
+#define PPP_IPV4_SUPPORT                1
+#endif
+
 /**
  * PPP_IPV6_SUPPORT==1: Enable PPP IPv6 support
  */

src/include/netif/ppp/ipcp.h

@@ -43,7 +43,7 @@
  */
 
 #include "lwip/opt.h"
-#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
+#if PPP_SUPPORT && PPP_IPV4_SUPPORT /* don't build if not configured for use in lwipopts.h */
 
 #ifndef IPCP_H
 #define	IPCP_H
@@ -104,4 +104,4 @@ char *ip_ntoa (u32_t);
 extern const struct protent ipcp_protent;
 
 #endif /* IPCP_H */
-#endif /* PPP_SUPPORT */
+#endif /* PPP_SUPPORT && PPP_IPV4_SUPPORT */

src/include/netif/ppp/ppp.h

@@ -153,7 +153,9 @@ typedef unsigned char  u_char;
 
 #include "fsm.h"
 #include "lcp.h"
+#if PPP_IPV4_SUPPORT
 #include "ipcp.h"
+#endif /* PPP_IPV4_SUPPORT */
 #if PPP_IPV6_SUPPORT
 #include "ipv6cp.h"
 #endif /* PPP_IPV6_SUPPORT */
@@ -287,8 +289,10 @@ typedef struct ppp_settings_s {
 } ppp_settings;
 
 struct ppp_addrs {
+#if PPP_IPV4_SUPPORT
   ip_addr_t our_ipaddr, his_ipaddr, netmask;
   ip_addr_t dns1, dns2;
+#endif /* PPP_IPV4_SUPPORT */
 #if PPP_IPV6_SUPPORT
   ip6_addr_t our6_ipaddr, his6_ipaddr;
 #endif /* PPP_IPV6_SUPPORT */
@@ -319,21 +323,21 @@ struct ppp_pcb_s {
   u8_t err_code;                 /* Code indicating why interface is down. */
 
   /* flags */
-  unsigned int if_up                   :1; /* True when the interface is up. */
-#if PPP_IPV6_SUPPORT
-  unsigned int if6_up                  :1; /* True when the IPv6 interface is up. */
-#else
-  unsigned int                         :1; /* 1 bit of padding */
-#endif /* PPP_IPV6_SUPPORT */
   unsigned int pcomp                   :1; /* Does peer accept protocol compression? */
   unsigned int accomp                  :1; /* Does peer accept addr/ctl compression? */
-  unsigned int proxy_arp_set           :1; /* Have created proxy arp entry */
+#if PPP_IPV4_SUPPORT
   unsigned int ipcp_is_open            :1; /* haven't called np_finished() */
   unsigned int ipcp_is_up              :1; /* have called ipcp_up() */
+  unsigned int if4_up                  :1; /* True when the IPv4 interface is up. */
+  unsigned int proxy_arp_set           :1; /* Have created proxy arp entry */
+#else
+  unsigned int                         :4; /* 4 bit of padding */
+#endif /* PPP_IPV4_SUPPORT */
 #if PPP_IPV6_SUPPORT
   unsigned int ipv6cp_is_up            :1; /* have called ip6cp_up() */
+  unsigned int if6_up                  :1; /* True when the IPv6 interface is up. */
 #else
-  unsigned int                         :1; /* 1 bit of padding */
+  unsigned int                         :2; /* 2 bit of padding */
 #endif /* PPP_IPV6_SUPPORT */
   unsigned int ask_for_local           :1; /* request our address from peer */
   unsigned int lcp_echo_timer_running  :1; /* set if a timer is running */
@@ -381,11 +385,13 @@ struct ppp_pcb_s {
   u8_t lcp_echo_number;          /* ID number of next echo frame */
   u16_t peer_mru;                /* currently negotiated peer MRU */
 
+#if PPP_IPV4_SUPPORT
   fsm ipcp_fsm;                   /* IPCP fsm structure */
   ipcp_options ipcp_wantoptions;  /* Options that we want to request */
   ipcp_options ipcp_gotoptions;   /* Options that peer ack'd */
   ipcp_options ipcp_allowoptions; /* Options we allow peer to request */
   ipcp_options ipcp_hisoptions;   /* Options that we ack'd */
+#endif /* PPP_IPV4_SUPPORT */
 
 #if PPP_IPV6_SUPPORT
   fsm ipv6cp_fsm;                     /* IPV6CP fsm structure */

src/include/netif/ppp/ppp_impl.h

@@ -424,21 +424,21 @@ void new_phase(ppp_pcb *pcb, int p);
 int ppp_send_config(ppp_pcb *pcb, int mtu, u32_t accm, int pcomp, int accomp);
 int ppp_recv_config(ppp_pcb *pcb, int mru, u32_t accm, int pcomp, int accomp);
 
+#if PPP_IPV4_SUPPORT
 int sifaddr(ppp_pcb *pcb, u32_t our_adr, u32_t his_adr, u32_t net_mask);
 int cifaddr(ppp_pcb *pcb, u32_t our_adr, u32_t his_adr);
+int sifproxyarp(ppp_pcb *pcb, u32_t his_adr);
+int cifproxyarp(ppp_pcb *pcb, u32_t his_adr);
+int sdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2);
+int cdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2);
+int sifvjcomp(ppp_pcb *pcb, int vjcomp, int cidcomp, int maxcid);
+int sifup(ppp_pcb *pcb);
+int sifdown (ppp_pcb *pcb);
+#endif /* PPP_IPV4_SUPPORT */
 
 #if PPP_IPV6_SUPPORT
 int sif6addr(ppp_pcb *pcb, eui64_t our_eui64, eui64_t his_eui64);
 int cif6addr(ppp_pcb *pcb, eui64_t our_eui64, eui64_t his_eui64);
-#endif /* PPP_IPV6_SUPPORT */
-
-int sdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2);
-int cdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2);
-
-int sifup(ppp_pcb *pcb);
-int sifdown (ppp_pcb *pcb);
-
-#if PPP_IPV6_SUPPORT
 int sif6up(ppp_pcb *pcb);
 int sif6down (ppp_pcb *pcb);
 #endif /* PPP_IPV6_SUPPORT */
@@ -448,11 +448,6 @@ int sifnpmode(ppp_pcb *pcb, int proto, enum NPmode mode);
 void netif_set_mtu(ppp_pcb *pcb, int mtu);
 int netif_get_mtu(ppp_pcb *pcb);
 
-int sifproxyarp(ppp_pcb *pcb, u32_t his_adr);
-int cifproxyarp(ppp_pcb *pcb, u32_t his_adr);
-
-int sifvjcomp(ppp_pcb *pcb, int vjcomp, int cidcomp, int maxcid);
-
 #if PPP_IDLETIMELIMIT
 int get_idle_time(ppp_pcb *pcb, struct ppp_idle *ip);
 #endif /* PPP_IDLETIMELIMIT */

src/netif/ppp/ipcp.c

@@ -41,7 +41,7 @@
  */
 
 #include "lwip/opt.h"
-#if PPP_SUPPORT /* don't build if not configured for use in lwipopts.h */
+#if PPP_SUPPORT && PPP_IPV4_SUPPORT /* don't build if not configured for use in lwipopts.h */
 
 /*
  * TODO:
@@ -2272,4 +2272,4 @@ ip_active_pkt(pkt, len)
 }
 #endif /* DEMAND_SUPPORT */
 
-#endif /* PPP_SUPPORT */
+#endif /* PPP_SUPPORT && PPP_IPV4_SUPPORT */

src/netif/ppp/ppp.c

@@ -100,7 +100,6 @@
 
 #include "netif/ppp/fsm.h"
 #include "netif/ppp/lcp.h"
-#include "netif/ppp/ipcp.h"
 #include "netif/ppp/magic.h"
 
 #if PAP_SUPPORT
@@ -121,6 +120,9 @@
 #if VJ_SUPPORT
 #include "netif/ppp/vj.h"
 #endif /* VJ_SUPPORT */
+#if PPP_IPV4_SUPPORT
+#include "netif/ppp/ipcp.h"
+#endif /* PPP_IPV4_SUPPORT */
 #if PPP_IPV6_SUPPORT
 #include "netif/ppp/ipv6cp.h"
 #endif /* PPP_IPV6_SUPPORT */
@@ -154,7 +156,9 @@ const struct protent* const protocols[] = {
 #if CBCP_SUPPORT
     &cbcp_protent,
 #endif /* CBCP_SUPPORT */
+#if PPP_IPV4_SUPPORT
     &ipcp_protent,
+#endif /* PPP_IPV4_SUPPORT */
 #if PPP_IPV6_SUPPORT
     &ipv6cp_protent,
 #endif /* PPP_IPV6_SUPPORT */
@@ -351,7 +355,10 @@ ppp_ioctl(ppp_pcb *pcb, u8_t cmd, void *arg)
       if (!arg) {
         goto fail;
       }
-      *(int *)arg = (int)(pcb->if_up
+      *(int *)arg = (int)(0
+#if PPP_IPV4_SUPPORT
+           || pcb->if4_up
+#endif /* PPP_IPV4_SUPPORT */
 #if PPP_IPV6_SUPPORT
            || pcb->if6_up
 #endif /* PPP_IPV6_SUPPORT */
@@ -424,6 +431,7 @@ static void ppp_do_open(void *arg) {
 static err_t ppp_netif_init_cb(struct netif *netif) {
   netif->name[0] = 'p';
   netif->name[1] = 'p';
+  /* FIXME: change that when netif_null_output_ip4() will materialize */
   netif->output = ppp_netif_output_ip4;
 #if PPP_IPV6_SUPPORT
   netif->output_ip6 = ppp_netif_output_ip6;
@@ -440,11 +448,12 @@ static err_t ppp_netif_init_cb(struct netif *netif) {
  * Send an IPv4 packet on the given connection.
  */
 static err_t ppp_netif_output_ip4(struct netif *netif, struct pbuf *pb, ip_addr_t *ipaddr) {
+#if PPP_IPV4_SUPPORT
   ppp_pcb *pcb = (ppp_pcb*)netif->state;
   LWIP_UNUSED_ARG(ipaddr);
 
   /* Check that the link is up. */
-  if (!pcb->if_up) {
+  if (!pcb->if4_up) {
     PPPDEBUG(LOG_ERR, ("ppp_netif_output_ip4[%d]: link not up\n", pcb->netif->num));
     LINK_STATS_INC(link.rterr);
     LINK_STATS_INC(link.drop);
@@ -453,6 +462,12 @@ static err_t ppp_netif_output_ip4(struct netif *netif, struct pbuf *pb, ip_addr_
   }
 
   return pcb->link_cb->netif_output(pcb, pcb->link_ctx_cb, pb, PPP_IP);
+#else /* PPP_IPV4_SUPPORT */
+  LWIP_UNUSED_ARG(netif);
+  LWIP_UNUSED_ARG(pb);
+  LWIP_UNUSED_ARG(ipaddr);
+  return ERR_IF;
+#endif /* PPP_IPV4_SUPPORT */
 }
 
 #if PPP_IPV6_SUPPORT
@@ -581,7 +596,9 @@ void ppp_clear(ppp_pcb *pcb) {
 #endif /* PPP_STATS_SUPPORT */
 
   memset(&pcb->phase, 0, sizeof(ppp_pcb) - ( (char*)&((ppp_pcb*)0)->phase - (char*)0 ) );
+#if PPP_IPV4_SUPPORT
   ip4_addr_set_u32(&pcb->addrs.netmask, IPADDR_BROADCAST);
+#endif /* PPP_IPV4_SUPPORT */
 
   /*
    * Initialize each protocol.
@@ -863,7 +880,7 @@ int ppp_recv_config(ppp_pcb *pcb, int mru, u32_t accm, int pcomp, int accomp) {
   return 0;
 }
 
-
+#if PPP_IPV4_SUPPORT
 /*
  * sifaddr - Config the interface IP addresses and netmask.
  */
@@ -876,7 +893,6 @@ int sifaddr(ppp_pcb *pcb, u32_t our_adr, u32_t his_adr,
   return 1;
 }
 
-
 /********************************************************************
  *
  * cifaddr - Clear the interface IP addresses, and delete routes
@@ -893,6 +909,104 @@ int cifaddr(ppp_pcb *pcb, u32_t our_adr, u32_t his_adr) {
   return 1;
 }
 
+/********************************************************************
+ *
+ * sifproxyarp - Make a proxy ARP entry for the peer.
+ */
+
+int sifproxyarp(ppp_pcb *pcb, u32_t his_adr) {
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(his_adr);
+  /* FIXME: do we really need that in IPCP ? */
+  return 0;
+}
+
+/********************************************************************
+ *
+ * cifproxyarp - Delete the proxy ARP entry for the peer.
+ */
+
+int cifproxyarp(ppp_pcb *pcb, u32_t his_adr) {
+  LWIP_UNUSED_ARG(pcb);
+  LWIP_UNUSED_ARG(his_adr);
+  /* FIXME: do we really need that in IPCP ? */
+  return 0;
+}
+
+/*
+ * sdns - Config the DNS servers
+ */
+int sdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2) {
+
+  ip4_addr_set_u32(&pcb->addrs.dns1, ns1);
+  ip4_addr_set_u32(&pcb->addrs.dns2, ns2);
+  return 1;
+}
+
+/********************************************************************
+ *
+ * cdns - Clear the DNS servers
+ */
+int cdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2) {
+
+  LWIP_UNUSED_ARG(ns1);
+  LWIP_UNUSED_ARG(ns2);
+
+  ip_addr_set_zero(&pcb->addrs.dns1);
+  ip_addr_set_zero(&pcb->addrs.dns2);
+  return 1;
+}
+
+/********************************************************************
+ *
+ * sifvjcomp - config tcp header compression
+ */
+int sifvjcomp(ppp_pcb *pcb, int vjcomp, int cidcomp, int maxcid) {
+  if (pcb->link_cb->vj_config) {
+    pcb->link_cb->vj_config(pcb, pcb->link_ctx_cb, vjcomp, cidcomp, maxcid);
+  }
+  return 0;
+}
+
+/*
+ * sifup - Config the interface up and enable IP packets to pass.
+ */
+int sifup(ppp_pcb *pcb) {
+
+  netif_set_addr(pcb->netif, &pcb->addrs.our_ipaddr, &pcb->addrs.netmask,
+                 &pcb->addrs.his_ipaddr);
+
+  netif_set_up(pcb->netif);
+  pcb->if4_up = 1;
+  pcb->err_code = PPPERR_NONE;
+
+  PPPDEBUG(LOG_DEBUG, ("sifup: unit %d: err_code=%d\n", pcb->netif->num, pcb->err_code));
+  pcb->link_status_cb(pcb, pcb->err_code, pcb->ctx_cb);
+  return 1;
+}
+
+/********************************************************************
+ *
+ * sifdown - Disable the indicated protocol and config the interface
+ *           down if there are no remaining protocols.
+ */
+int sifdown(ppp_pcb *pcb) {
+
+  pcb->if4_up = 0;
+
+  if (1
+#if PPP_IPV6_SUPPORT
+   /* set the interface down if IPv6 is down as well */
+   && !pcb->if6_up
+#endif /* PPP_IPV6_SUPPORT */
+  ) {
+    /* make sure the netif status callback is called */
+    netif_set_down(pcb->netif);
+  }
+  PPPDEBUG(LOG_DEBUG, ("sifdown: unit %d: err_code=%d\n", pcb->netif->num, pcb->err_code));
+  return 1;
+}
+#endif /* PPP_IPV4_SUPPORT */
 
 #if PPP_IPV6_SUPPORT
 #define IN6_LLADDR_FROM_EUI64(ip6, eui64) do {    \
@@ -925,75 +1039,7 @@ int cif6addr(ppp_pcb *pcb, eui64_t our_eui64, eui64_t his_eui64) {
   ip6_addr_set_zero(&pcb->addrs.his6_ipaddr);
   return 1;
 }
-#endif /* PPP_IPV6_SUPPORT */
 
-
-/*
- * sdns - Config the DNS servers
- */
-int sdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2) {
-
-  ip4_addr_set_u32(&pcb->addrs.dns1, ns1);
-  ip4_addr_set_u32(&pcb->addrs.dns2, ns2);
-  return 1;
-}
-
-
-/********************************************************************
- *
- * cdns - Clear the DNS servers
- */
-int cdns(ppp_pcb *pcb, u32_t ns1, u32_t ns2) {
-
-  LWIP_UNUSED_ARG(ns1);
-  LWIP_UNUSED_ARG(ns2);
-
-  ip_addr_set_zero(&pcb->addrs.dns1);
-  ip_addr_set_zero(&pcb->addrs.dns2);
-  return 1;
-}
-
-
-/*
- * sifup - Config the interface up and enable IP packets to pass.
- */
-int sifup(ppp_pcb *pcb) {
-
-  netif_set_addr(pcb->netif, &pcb->addrs.our_ipaddr, &pcb->addrs.netmask,
-                 &pcb->addrs.his_ipaddr);
-
-  netif_set_up(pcb->netif);
-  pcb->if_up = 1;
-  pcb->err_code = PPPERR_NONE;
-
-  PPPDEBUG(LOG_DEBUG, ("sifup: unit %d: err_code=%d\n", pcb->netif->num, pcb->err_code));
-  pcb->link_status_cb(pcb, pcb->err_code, pcb->ctx_cb);
-  return 1;
-}
-
-/********************************************************************
- *
- * sifdown - Disable the indicated protocol and config the interface
- *	     down if there are no remaining protocols.
- */
-int sifdown(ppp_pcb *pcb) {
-
-  pcb->if_up = 0;
-
-  if (1
-#if PPP_IPV6_SUPPORT
-   /* set the interface down if IPv6 is down as well */
-   && !pcb->if6_up
-#endif /* PPP_IPV6_SUPPORT */
-  ) {
-    /* make sure the netif status callback is called */
-    netif_set_down(pcb->netif);
-  }
-  PPPDEBUG(LOG_DEBUG, ("sifdown: unit %d: err_code=%d\n", pcb->netif->num, pcb->err_code));
-  return 1;
-}
-
-#if PPP_IPV6_SUPPORT
 /*
  * sif6up - Config the interface up and enable IPv6 packets to pass.
  */
@@ -1020,7 +1066,12 @@ int sif6down(ppp_pcb *pcb) {
 
   pcb->if6_up = 0;
   /* set the interface down if IPv4 is down as well */
-  if (!pcb->if_up) {
+  if (1
+#if PPP_IPV4_SUPPORT
+   /* set the interface down if IPv6 is down as well */
+   && !pcb->if4_up
+#endif /* PPP_IPV4_SUPPORT */
+  ) {
     /* make sure the netif status callback is called */
     netif_set_down(pcb->netif);
   }
@@ -1055,41 +1106,6 @@ int netif_get_mtu(ppp_pcb *pcb) {
   return pcb->netif->mtu;
 }
 
-/********************************************************************
- *
- * sifproxyarp - Make a proxy ARP entry for the peer.
- */
-
-int sifproxyarp(ppp_pcb *pcb, u32_t his_adr) {
-  LWIP_UNUSED_ARG(pcb);
-  LWIP_UNUSED_ARG(his_adr);
-  /* FIXME: do we really need that in IPCP ? */
-  return 0;
-}
-
-/********************************************************************
- *
- * cifproxyarp - Delete the proxy ARP entry for the peer.
- */
-
-int cifproxyarp(ppp_pcb *pcb, u32_t his_adr) {
-  LWIP_UNUSED_ARG(pcb);
-  LWIP_UNUSED_ARG(his_adr);
-  /* FIXME: do we really need that in IPCP ? */
-  return 0;
-}
-
-/********************************************************************
- *
- * sifvjcomp - config tcp header compression
- */
-int sifvjcomp(ppp_pcb *pcb, int vjcomp, int cidcomp, int maxcid) {
-  if (pcb->link_cb->vj_config) {
-    pcb->link_cb->vj_config(pcb, pcb->link_ctx_cb, vjcomp, cidcomp, maxcid);
-  }
-  return 0;
-}
-
 #if PPP_IDLETIMELIMIT
 /********************************************************************
  *

src/netif/ppp/pppoe.c

@@ -907,8 +907,10 @@ pppoe_connect(ppp_pcb *ppp, void *ctx)
   struct pppoe_softc *sc = (struct pppoe_softc *)ctx;
   lcp_options *lcp_wo;
   lcp_options *lcp_ao;
+#if PPP_IPV4_SUPPORT
   ipcp_options *ipcp_wo;
   ipcp_options *ipcp_ao;
+#endif /* PPP_IPV4_SUPPORT */
 
   if (sc->sc_state != PPPOE_STATE_INITIAL) {
     return EBUSY;
@@ -940,6 +942,7 @@ pppoe_connect(ppp_pcb *ppp, void *ctx)
   lcp_ao->neg_pcompression = 0;
   lcp_ao->neg_accompression = 0;
 
+#if PPP_IPV4_SUPPORT
   ipcp_wo = &ppp->ipcp_wantoptions;
   ipcp_wo->neg_vj = 0;
   ipcp_wo->old_vj = 0;
@@ -947,6 +950,7 @@ pppoe_connect(ppp_pcb *ppp, void *ctx)
   ipcp_ao = &ppp->ipcp_allowoptions;
   ipcp_ao->neg_vj = 0;
   ipcp_ao->old_vj = 0;
+#endif /* PPP_IPV4_SUPPORT */
 
   /* save state, in case we fail to send PADI */
   sc->sc_state = PPPOE_STATE_PADI_SENT;

src/netif/ppp/pppol2tp.c

@@ -258,8 +258,10 @@ static err_t pppol2tp_connect(ppp_pcb *ppp, void *ctx) {
   pppol2tp_pcb *l2tp = (pppol2tp_pcb *)ctx;
   lcp_options *lcp_wo;
   lcp_options *lcp_ao;
+#if PPP_IPV4_SUPPORT
   ipcp_options *ipcp_wo;
   ipcp_options *ipcp_ao;
+#endif /* PPP_IPV4_SUPPORT */
 
   if (l2tp->phase != PPPOL2TP_STATE_INITIAL) {
     return ERR_VAL;
@@ -281,6 +283,7 @@ static err_t pppol2tp_connect(ppp_pcb *ppp, void *ctx) {
   lcp_ao->neg_pcompression = 0;
   lcp_ao->neg_accompression = 0;
 
+#if PPP_IPV4_SUPPORT
   ipcp_wo = &ppp->ipcp_wantoptions;
   ipcp_wo->neg_vj = 0;
   ipcp_wo->old_vj = 0;
@@ -288,6 +291,7 @@ static err_t pppol2tp_connect(ppp_pcb *ppp, void *ctx) {
   ipcp_ao = &ppp->ipcp_allowoptions;
   ipcp_ao->neg_vj = 0;
   ipcp_ao->old_vj = 0;
+#endif /* PPP_IPV4_SUPPORT */
 
   /* Listen to a random source port, we need to do that instead of using udp_connect()
    * because the L2TP LNS might answer with its own random source port (!= 1701)

src/netif/ppp/pppos.c

@@ -382,10 +382,10 @@ static err_t
 pppos_connect(ppp_pcb *ppp, void *ctx)
 {
   pppos_pcb *pppos = (pppos_pcb *)ctx;
-#if !VJ_SUPPORT
+#if !VJ_SUPPORT && PPP_IPV4_SUPPORT
   ipcp_options *ipcp_wo;
   ipcp_options *ipcp_ao;
-#endif /* !VJ_SUPPORT */
+#endif /* !VJ_SUPPORT && PPP_IPV4_SUPPORT */
 
   /* input pbuf left over from last session? */
   pppos_free_current_input_packet(pppos);
@@ -394,6 +394,7 @@ pppos_connect(ppp_pcb *ppp, void *ctx)
   /* reset PPPoS control block to its initial state */
   memset(&pppos->out_accm, 0, sizeof(pppos_pcb) - ( (char*)&((pppos_pcb*)0)->out_accm - (char*)0 ) );
 
+#if PPP_IPV4_SUPPORT
 #if VJ_SUPPORT
   vj_compress_init(&pppos->vj_comp);
 #else /* VJ_SUPPORT */
@@ -406,6 +407,7 @@ pppos_connect(ppp_pcb *ppp, void *ctx)
   ipcp_ao->neg_vj = 0;
   ipcp_ao->old_vj = 0;
 #endif /* VJ_SUPPORT */
+#endif /* PPP_IPV4_SUPPORT */
 
   /*
    * Default the in and out accm so that escape and flag characters