[IPV6] IP6TUNNEL: Enable to control the handled inner protocol.

ip6_tunnel before supporting IPv4/IPv6 tunnel allows only IPPROTO_IPV6
in configurations from userland. This allows userland to set IPPROTO_IPIP
and 0(wildcard). ip6_tunnel only handles allowed inner protocols.

Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 70684e0d31f19dc267fd5dc58049bc21ef7b530b..d8c84d8d7cf8654adfb3d1347921191bc778891c 100644 (file)
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -384,7 +384,7 @@ parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
  **/
 
 static int
-ip6_tnl_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+ip6_tnl_err(struct sk_buff *skb, __u8 ipproto, struct inet6_skb_parm *opt,
            int *type, int *code, int *msg, __be32 *info, int offset)
 {
        struct ipv6hdr *ipv6h = (struct ipv6hdr *) skb->data;
@@ -404,6 +404,9 @@ ip6_tnl_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
        if ((t = ip6_tnl_lookup(&ipv6h->daddr, &ipv6h->saddr)) == NULL)
                goto out;
 
+       if (t->parms.proto != ipproto && t->parms.proto != 0)
+               goto out;
+
        err = 0;
 
        switch (*type) {
@@ -487,8 +490,8 @@ ip4ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
        struct flowi fl;
        struct rtable *rt;
 
-       err = ip6_tnl_err(skb, opt, &rel_type, &rel_code, &rel_msg, &rel_info,
-                         offset);
+       err = ip6_tnl_err(skb, IPPROTO_IPIP, opt, &rel_type, &rel_code,
+                         &rel_msg, &rel_info, offset);
        if (err < 0)
                return err;
 
@@ -581,8 +584,8 @@ ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
        __u32 rel_info = info;
        int err;
 
-       err = ip6_tnl_err(skb, opt, &rel_type, &rel_code, &rel_msg, &rel_info,
-                         offset);
+       err = ip6_tnl_err(skb, IPPROTO_IPV6, opt, &rel_type, &rel_code,
+                         &rel_msg, &rel_info, offset);
        if (err < 0)
                return err;
 
@@ -671,6 +674,7 @@ static inline int ip6_tnl_rcv_ctl(struct ip6_tnl *t)
  **/
 
 static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
+                      __u8 ipproto,
                       void (*dscp_ecn_decapsulate)(struct ip6_tnl *t,
                                                    struct ipv6hdr *ipv6h,
                                                    struct sk_buff *skb))
@@ -683,6 +687,11 @@ static int ip6_tnl_rcv(struct sk_buff *skb, __u16 protocol,
        read_lock(&ip6_tnl_lock);
 
        if ((t = ip6_tnl_lookup(&ipv6h->saddr, &ipv6h->daddr)) != NULL) {
+               if (t->parms.proto != ipproto && t->parms.proto != 0) {
+                       read_unlock(&ip6_tnl_lock);
+                       goto discard;
+               }
+
                if (!xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
                        read_unlock(&ip6_tnl_lock);
                        goto discard;
@@ -722,12 +731,14 @@ discard:
 
 static int ip4ip6_rcv(struct sk_buff *skb)
 {
-       return ip6_tnl_rcv(skb, ETH_P_IP, ip4ip6_dscp_ecn_decapsulate);
+       return ip6_tnl_rcv(skb, ETH_P_IP, IPPROTO_IPIP,
+                          ip4ip6_dscp_ecn_decapsulate);
 }
 
 static int ip6ip6_rcv(struct sk_buff *skb)
 {
-       return ip6_tnl_rcv(skb, ETH_P_IPV6, ip6ip6_dscp_ecn_decapsulate);
+       return ip6_tnl_rcv(skb, ETH_P_IPV6, IPPROTO_IPV6,
+                          ip6ip6_dscp_ecn_decapsulate);
 }
 
 struct ipv6_tel_txoption {
@@ -939,7 +950,8 @@ ip4ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
        __u32 mtu;
        int err;
 
-       if (!ip6_tnl_xmit_ctl(t))
+       if ((t->parms.proto != IPPROTO_IPIP && t->parms.proto != 0) ||
+           !ip6_tnl_xmit_ctl(t))
                return -1;
 
        if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
@@ -978,7 +990,8 @@ ip6ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev)
        __u32 mtu;
        int err;
 
-       if (!ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
+       if ((t->parms.proto != IPPROTO_IPV6 && t->parms.proto != 0) ||
+           !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
                return -1;
 
        if ((offset = parse_tlv_tnl_enc_lim(skb, skb->nh.raw)) > 0) {
@@ -1140,6 +1153,7 @@ ip6_tnl_change(struct ip6_tnl *t, struct ip6_tnl_parm *p)
        t->parms.encap_limit = p->encap_limit;
        t->parms.flowinfo = p->flowinfo;
        t->parms.link = p->link;
+       t->parms.proto = p->proto;
        ip6_tnl_dst_reset(t);
        ip6_tnl_link_config(t);
        return 0;
@@ -1205,7 +1219,8 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
                if (copy_from_user(&p, ifr->ifr_ifru.ifru_data, sizeof (p)))
                        break;
                err = -EINVAL;
-               if (p.proto != IPPROTO_IPV6)
+               if (p.proto != IPPROTO_IPV6 && p.proto != IPPROTO_IPIP &&
+                   p.proto != 0)
                        break;
                t = ip6_tnl_locate(&p, cmd == SIOCADDTUNNEL);
                if (dev != ip6_fb_tnl_dev && cmd == SIOCCHGTUNNEL) {
@@ -1324,7 +1339,6 @@ static inline void
 ip6_tnl_dev_init_gen(struct net_device *dev)
 {
        struct ip6_tnl *t = netdev_priv(dev);
-       t->fl.proto = IPPROTO_IPV6;
        t->dev = dev;
        strcpy(t->parms.name, dev->name);
 }
@@ -1355,6 +1369,7 @@ ip6_fb_tnl_dev_init(struct net_device *dev)
 {
        struct ip6_tnl *t = netdev_priv(dev);
        ip6_tnl_dev_init_gen(dev);
+       t->parms.proto = IPPROTO_IPV6;
        dev_hold(dev);
        tnls_wc[0] = t;
        return 0;