From 058214a4d1dfefed9f01a277fadd3590acb5f990 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Wed, 18 May 2016 09:06:17 -0700 Subject: ip6_tun: Add infrastructure for doing encapsulation Add encap_hlen and ip_tunnel_encap structure to ip6_tnl. Add functions for getting encap hlen, setting up encap on a tunnel, performing encapsulation operation. Signed-off-by: Tom Herbert Signed-off-by: David S. Miller diff --git a/include/net/ip6_tunnel.h b/include/net/ip6_tunnel.h index fb9e015..d325c81 100644 --- a/include/net/ip6_tunnel.h +++ b/include/net/ip6_tunnel.h @@ -52,10 +52,68 @@ struct ip6_tnl { __u32 o_seqno; /* The last output seqno */ int hlen; /* tun_hlen + encap_hlen */ int tun_hlen; /* Precalculated header length */ + int encap_hlen; /* Encap header length (FOU,GUE) */ + struct ip_tunnel_encap encap; int mlink; +}; +struct ip6_tnl_encap_ops { + size_t (*encap_hlen)(struct ip_tunnel_encap *e); + int (*build_header)(struct sk_buff *skb, struct ip_tunnel_encap *e, + u8 *protocol, struct flowi6 *fl6); }; +extern const struct ip6_tnl_encap_ops __rcu * + ip6tun_encaps[MAX_IPTUN_ENCAP_OPS]; + +int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, + unsigned int num); +int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, + unsigned int num); +int ip6_tnl_encap_setup(struct ip6_tnl *t, + struct ip_tunnel_encap *ipencap); + +static inline int ip6_encap_hlen(struct ip_tunnel_encap *e) +{ + const struct ip6_tnl_encap_ops *ops; + int hlen = -EINVAL; + + if (e->type == TUNNEL_ENCAP_NONE) + return 0; + + if (e->type >= MAX_IPTUN_ENCAP_OPS) + return -EINVAL; + + rcu_read_lock(); + ops = rcu_dereference(ip6tun_encaps[e->type]); + if (likely(ops && ops->encap_hlen)) + hlen = ops->encap_hlen(e); + rcu_read_unlock(); + + return hlen; +} + +static inline int ip6_tnl_encap(struct sk_buff *skb, struct ip6_tnl *t, + u8 *protocol, struct flowi6 *fl6) +{ + const struct ip6_tnl_encap_ops *ops; + int ret = -EINVAL; + + if (t->encap.type == TUNNEL_ENCAP_NONE) + return 0; + + if (t->encap.type >= MAX_IPTUN_ENCAP_OPS) + return -EINVAL; + + rcu_read_lock(); + ops = rcu_dereference(ip6tun_encaps[t->encap.type]); + if (likely(ops && ops->build_header)) + ret = ops->build_header(skb, &t->encap, protocol, fl6); + rcu_read_unlock(); + + return ret; +} + /* Tunnel encapsulation limit destination sub-option */ struct ipv6_tlv_tnl_enc_lim { diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c index cc66a20..afd6b59 100644 --- a/net/ipv4/ip_tunnel_core.c +++ b/net/ipv4/ip_tunnel_core.c @@ -37,6 +37,7 @@ #include #include #include +#include #include #include #include @@ -51,6 +52,10 @@ const struct ip_tunnel_encap_ops __rcu * iptun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; EXPORT_SYMBOL(iptun_encaps); +const struct ip6_tnl_encap_ops __rcu * + ip6tun_encaps[MAX_IPTUN_ENCAP_OPS] __read_mostly; +EXPORT_SYMBOL(ip6tun_encaps); + void iptunnel_xmit(struct sock *sk, struct rtable *rt, struct sk_buff *skb, __be32 src, __be32 dst, __u8 proto, __u8 tos, __u8 ttl, __be16 df, bool xnet) diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c index e79330f..64ddbeac 100644 --- a/net/ipv6/ip6_tunnel.c +++ b/net/ipv6/ip6_tunnel.c @@ -1010,7 +1010,8 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, struct dst_entry *dst = NULL, *ndst = NULL; struct net_device *tdev; int mtu; - unsigned int max_headroom = sizeof(struct ipv6hdr); + unsigned int psh_hlen = sizeof(struct ipv6hdr) + t->encap_hlen; + unsigned int max_headroom = psh_hlen; int err = -1; /* NBMA tunnel */ @@ -1063,7 +1064,7 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, t->parms.name); goto tx_err_dst_release; } - mtu = dst_mtu(dst) - sizeof(*ipv6h); + mtu = dst_mtu(dst) - psh_hlen; if (encap_limit >= 0) { max_headroom += 8; mtu -= 8; @@ -1124,11 +1125,18 @@ int ip6_tnl_xmit(struct sk_buff *skb, struct net_device *dev, __u8 dsfield, skb->encapsulation = 1; } + /* Calculate max headroom for all the headers and adjust + * needed_headroom if necessary. + */ max_headroom = LL_RESERVED_SPACE(dst->dev) + sizeof(struct ipv6hdr) - + dst->header_len; + + dst->header_len + t->hlen; if (max_headroom > dev->needed_headroom) dev->needed_headroom = max_headroom; + err = ip6_tnl_encap(skb, t, &proto, fl6); + if (err) + return err; + skb_push(skb, sizeof(struct ipv6hdr)); skb_reset_network_header(skb); ipv6h = ipv6_hdr(skb); @@ -1280,6 +1288,7 @@ static void ip6_tnl_link_config(struct ip6_tnl *t) struct net_device *dev = t->dev; struct __ip6_tnl_parm *p = &t->parms; struct flowi6 *fl6 = &t->fl.u.ip6; + int t_hlen; memcpy(dev->dev_addr, &p->laddr, sizeof(struct in6_addr)); memcpy(dev->broadcast, &p->raddr, sizeof(struct in6_addr)); @@ -1303,6 +1312,10 @@ static void ip6_tnl_link_config(struct ip6_tnl *t) else dev->flags &= ~IFF_POINTOPOINT; + t->tun_hlen = 0; + t->hlen = t->encap_hlen + t->tun_hlen; + t_hlen = t->hlen + sizeof(struct ipv6hdr); + if (p->flags & IP6_TNL_F_CAP_XMIT) { int strict = (ipv6_addr_type(&p->raddr) & (IPV6_ADDR_MULTICAST|IPV6_ADDR_LINKLOCAL)); @@ -1316,9 +1329,9 @@ static void ip6_tnl_link_config(struct ip6_tnl *t) if (rt->dst.dev) { dev->hard_header_len = rt->dst.dev->hard_header_len + - sizeof(struct ipv6hdr); + t_hlen; - dev->mtu = rt->dst.dev->mtu - sizeof(struct ipv6hdr); + dev->mtu = rt->dst.dev->mtu - t_hlen; if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) dev->mtu -= 8; @@ -1564,6 +1577,59 @@ int ip6_tnl_get_iflink(const struct net_device *dev) } EXPORT_SYMBOL(ip6_tnl_get_iflink); +int ip6_tnl_encap_add_ops(const struct ip6_tnl_encap_ops *ops, + unsigned int num) +{ + if (num >= MAX_IPTUN_ENCAP_OPS) + return -ERANGE; + + return !cmpxchg((const struct ip6_tnl_encap_ops **) + &ip6tun_encaps[num], + NULL, ops) ? 0 : -1; +} +EXPORT_SYMBOL(ip6_tnl_encap_add_ops); + +int ip6_tnl_encap_del_ops(const struct ip6_tnl_encap_ops *ops, + unsigned int num) +{ + int ret; + + if (num >= MAX_IPTUN_ENCAP_OPS) + return -ERANGE; + + ret = (cmpxchg((const struct ip6_tnl_encap_ops **) + &ip6tun_encaps[num], + ops, NULL) == ops) ? 0 : -1; + + synchronize_net(); + + return ret; +} +EXPORT_SYMBOL(ip6_tnl_encap_del_ops); + +int ip6_tnl_encap_setup(struct ip6_tnl *t, + struct ip_tunnel_encap *ipencap) +{ + int hlen; + + memset(&t->encap, 0, sizeof(t->encap)); + + hlen = ip6_encap_hlen(ipencap); + if (hlen < 0) + return hlen; + + t->encap.type = ipencap->type; + t->encap.sport = ipencap->sport; + t->encap.dport = ipencap->dport; + t->encap.flags = ipencap->flags; + + t->encap_hlen = hlen; + t->hlen = t->encap_hlen + t->tun_hlen; + + return 0; +} +EXPORT_SYMBOL_GPL(ip6_tnl_encap_setup); + static const struct net_device_ops ip6_tnl_netdev_ops = { .ndo_init = ip6_tnl_dev_init, .ndo_uninit = ip6_tnl_dev_uninit, @@ -1585,19 +1651,13 @@ static const struct net_device_ops ip6_tnl_netdev_ops = { static void ip6_tnl_dev_setup(struct net_device *dev) { - struct ip6_tnl *t; - dev->netdev_ops = &ip6_tnl_netdev_ops; dev->destructor = ip6_dev_free; dev->type = ARPHRD_TUNNEL6; - dev->hard_header_len = LL_MAX_HEADER + sizeof(struct ipv6hdr); - dev->mtu = ETH_DATA_LEN - sizeof(struct ipv6hdr); - t = netdev_priv(dev); - if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) - dev->mtu -= 8; dev->flags |= IFF_NOARP; dev->addr_len = sizeof(struct in6_addr); + dev->features |= NETIF_F_LLTX; netif_keep_dst(dev); /* This perm addr will be used as interface identifier by IPv6 */ dev->addr_assign_type = NET_ADDR_RANDOM; @@ -1615,6 +1675,7 @@ ip6_tnl_dev_init_gen(struct net_device *dev) { struct ip6_tnl *t = netdev_priv(dev); int ret; + int t_hlen; t->dev = dev; t->net = dev_net(dev); @@ -1630,8 +1691,15 @@ ip6_tnl_dev_init_gen(struct net_device *dev) if (ret) goto destroy_dst; - t->hlen = 0; t->tun_hlen = 0; + t->hlen = t->encap_hlen + t->tun_hlen; + t_hlen = t->hlen + sizeof(struct ipv6hdr); + + dev->type = ARPHRD_TUNNEL6; + dev->hard_header_len = LL_MAX_HEADER + t_hlen; + dev->mtu = ETH_DATA_LEN - t_hlen; + if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT)) + dev->mtu -= 8; return 0; -- cgit v0.10.2