// SPDX-License-Identifier: GPL-2.0-or-later /* * IPv6 over IPv4 tunnel device - Simple Internet Transition (SIT) * Linux INET6 implementation * * Authors: * Pedro Roque <[email protected]> * Alexey Kuznetsov <[email protected]> * * Changes: * Roger Venning <[email protected]>: 6to4 support * Nate Thompson <[email protected]>: 6to4 support * Fred Templin <[email protected]>: isatap support */ #define pr_fmt(fmt) … #include <linux/module.h> #include <linux/capability.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/net.h> #include <linux/in6.h> #include <linux/netdevice.h> #include <linux/if_arp.h> #include <linux/icmp.h> #include <linux/slab.h> #include <linux/uaccess.h> #include <linux/init.h> #include <linux/netfilter_ipv4.h> #include <linux/if_ether.h> #include <net/sock.h> #include <net/snmp.h> #include <net/ipv6.h> #include <net/protocol.h> #include <net/transp_v6.h> #include <net/ip6_fib.h> #include <net/ip6_route.h> #include <net/ndisc.h> #include <net/addrconf.h> #include <net/ip.h> #include <net/udp.h> #include <net/icmp.h> #include <net/ip_tunnels.h> #include <net/inet_ecn.h> #include <net/xfrm.h> #include <net/dsfield.h> #include <net/net_namespace.h> #include <net/netns/generic.h> /* This version of net/ipv6/sit.c is cloned of net/ipv4/ip_gre.c For comments look at net/ipv4/ip_gre.c --ANK */ #define IP6_SIT_HASH_SIZE … #define HASH(addr) … static bool log_ecn_error = …; module_param(log_ecn_error, bool, 0644); MODULE_PARM_DESC(…) …; static int ipip6_tunnel_init(struct net_device *dev); static void ipip6_tunnel_setup(struct net_device *dev); static void ipip6_dev_free(struct net_device *dev); static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, __be32 *v4dst); static struct rtnl_link_ops sit_link_ops __read_mostly; static unsigned int sit_net_id __read_mostly; struct sit_net { … }; static inline struct sit_net *dev_to_sit_net(struct net_device *dev) { … } /* * Must be invoked with rcu_read_lock */ static struct ip_tunnel *ipip6_tunnel_lookup(struct net *net, struct net_device *dev, __be32 remote, __be32 local, int sifindex) { … } static struct ip_tunnel __rcu ** __ipip6_bucket(struct sit_net *sitn, struct ip_tunnel_parm_kern *parms) { … } static inline struct ip_tunnel __rcu **ipip6_bucket(struct sit_net *sitn, struct ip_tunnel *t) { … } static void ipip6_tunnel_unlink(struct sit_net *sitn, struct ip_tunnel *t) { … } static void ipip6_tunnel_link(struct sit_net *sitn, struct ip_tunnel *t) { … } static void ipip6_tunnel_clone_6rd(struct net_device *dev, struct sit_net *sitn) { … } static int ipip6_tunnel_create(struct net_device *dev) { … } static struct ip_tunnel *ipip6_tunnel_locate(struct net *net, struct ip_tunnel_parm_kern *parms, int create) { … } #define for_each_prl_rcu(start) … static struct ip_tunnel_prl_entry * __ipip6_tunnel_locate_prl(struct ip_tunnel *t, __be32 addr) { … } static int ipip6_tunnel_get_prl(struct net_device *dev, struct ip_tunnel_prl __user *a) { … } static int ipip6_tunnel_add_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a, int chg) { … } static void prl_list_destroy_rcu(struct rcu_head *head) { … } static int ipip6_tunnel_del_prl(struct ip_tunnel *t, struct ip_tunnel_prl *a) { … } static int ipip6_tunnel_prl_ctl(struct net_device *dev, struct ip_tunnel_prl __user *data, int cmd) { … } static int isatap_chksrc(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *t) { … } static void ipip6_tunnel_uninit(struct net_device *dev) { … } static int ipip6_err(struct sk_buff *skb, u32 info) { … } static inline bool is_spoofed_6rd(struct ip_tunnel *tunnel, const __be32 v4addr, const struct in6_addr *v6addr) { … } /* Checks if an address matches an address on the tunnel interface. * Used to detect the NAT of proto 41 packets and let them pass spoofing test. * Long story: * This function is called after we considered the packet as spoofed * in is_spoofed_6rd. * We may have a router that is doing NAT for proto 41 packets * for an internal station. Destination a.a.a.a/PREFIX:bbbb:bbbb * will be translated to n.n.n.n/PREFIX:bbbb:bbbb. And is_spoofed_6rd * function will return true, dropping the packet. * But, we can still check if is spoofed against the IP * addresses associated with the interface. */ static bool only_dnatted(const struct ip_tunnel *tunnel, const struct in6_addr *v6dst) { … } /* Returns true if a packet is spoofed */ static bool packet_is_spoofed(struct sk_buff *skb, const struct iphdr *iph, struct ip_tunnel *tunnel) { … } static int ipip6_rcv(struct sk_buff *skb) { … } static const struct tnl_ptk_info ipip_tpi = …; #if IS_ENABLED(CONFIG_MPLS) static const struct tnl_ptk_info mplsip_tpi = …; #endif static int sit_tunnel_rcv(struct sk_buff *skb, u8 ipproto) { … } static int ipip_rcv(struct sk_buff *skb) { … } #if IS_ENABLED(CONFIG_MPLS) static int mplsip_rcv(struct sk_buff *skb) { … } #endif /* * If the IPv6 address comes from 6rd / 6to4 (RFC 3056) addr space this function * stores the embedded IPv4 address in v4dst and returns true. */ static bool check_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst, __be32 *v4dst) { … } static inline __be32 try_6rd(struct ip_tunnel *tunnel, const struct in6_addr *v6dst) { … } /* * This function assumes it is being called from dev_queue_xmit() * and that skb is filled properly by that function. */ static netdev_tx_t ipip6_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { … } static netdev_tx_t sit_tunnel_xmit__(struct sk_buff *skb, struct net_device *dev, u8 ipproto) { … } static netdev_tx_t sit_tunnel_xmit(struct sk_buff *skb, struct net_device *dev) { … } static void ipip6_tunnel_bind_dev(struct net_device *dev) { … } static void ipip6_tunnel_update(struct ip_tunnel *t, struct ip_tunnel_parm_kern *p, __u32 fwmark) { … } #ifdef CONFIG_IPV6_SIT_6RD static int ipip6_tunnel_update_6rd(struct ip_tunnel *t, struct ip_tunnel_6rd *ip6rd) { … } static int ipip6_tunnel_get6rd(struct net_device *dev, struct ip_tunnel_parm __user *data) { … } static int ipip6_tunnel_6rdctl(struct net_device *dev, struct ip_tunnel_6rd __user *data, int cmd) { … } #endif /* CONFIG_IPV6_SIT_6RD */ static bool ipip6_valid_ip_proto(u8 ipproto) { … } static int __ipip6_tunnel_ioctl_validate(struct net *net, struct ip_tunnel_parm_kern *p) { … } static int ipip6_tunnel_get(struct net_device *dev, struct ip_tunnel_parm_kern *p) { … } static int ipip6_tunnel_add(struct net_device *dev, struct ip_tunnel_parm_kern *p) { … } static int ipip6_tunnel_change(struct net_device *dev, struct ip_tunnel_parm_kern *p) { … } static int ipip6_tunnel_del(struct net_device *dev, struct ip_tunnel_parm_kern *p) { … } static int ipip6_tunnel_ctl(struct net_device *dev, struct ip_tunnel_parm_kern *p, int cmd) { … } static int ipip6_tunnel_siocdevprivate(struct net_device *dev, struct ifreq *ifr, void __user *data, int cmd) { … } static const struct net_device_ops ipip6_netdev_ops = …; static void ipip6_dev_free(struct net_device *dev) { … } #define SIT_FEATURES … static void ipip6_tunnel_setup(struct net_device *dev) { … } static int ipip6_tunnel_init(struct net_device *dev) { … } static void __net_init ipip6_fb_tunnel_init(struct net_device *dev) { … } static int ipip6_validate(struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { … } static void ipip6_netlink_parms(struct nlattr *data[], struct ip_tunnel_parm_kern *parms, __u32 *fwmark) { … } #ifdef CONFIG_IPV6_SIT_6RD /* This function returns true when 6RD attributes are present in the nl msg */ static bool ipip6_netlink_6rd_parms(struct nlattr *data[], struct ip_tunnel_6rd *ip6rd) { … } #endif static int ipip6_newlink(struct net *src_net, struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { … } static int ipip6_changelink(struct net_device *dev, struct nlattr *tb[], struct nlattr *data[], struct netlink_ext_ack *extack) { … } static size_t ipip6_get_size(const struct net_device *dev) { … } static int ipip6_fill_info(struct sk_buff *skb, const struct net_device *dev) { … } static const struct nla_policy ipip6_policy[IFLA_IPTUN_MAX + 1] = …; static void ipip6_dellink(struct net_device *dev, struct list_head *head) { … } static struct rtnl_link_ops sit_link_ops __read_mostly = …; static struct xfrm_tunnel sit_handler __read_mostly = …; static struct xfrm_tunnel ipip_handler __read_mostly = …; #if IS_ENABLED(CONFIG_MPLS) static struct xfrm_tunnel mplsip_handler __read_mostly = …; #endif static void __net_exit sit_destroy_tunnels(struct net *net, struct list_head *head) { … } static int __net_init sit_init_net(struct net *net) { … } static void __net_exit sit_exit_batch_rtnl(struct list_head *net_list, struct list_head *dev_to_kill) { … } static struct pernet_operations sit_net_ops = …; static void __exit sit_cleanup(void) { … } static int __init sit_init(void) { … } module_init(…) …; module_exit(sit_cleanup); MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …; MODULE_ALIAS_RTNL_LINK(…) …; MODULE_ALIAS_NETDEV(…) …;
Codebase Browser
linux