diff options
Diffstat (limited to 'net/ipv6/xfrm6_policy.c')
-rw-r--r-- | net/ipv6/xfrm6_policy.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c new file mode 100644 index 00000000..8ea65e03 --- /dev/null +++ b/net/ipv6/xfrm6_policy.c @@ -0,0 +1,357 @@ +/* + * xfrm6_policy.c: based on xfrm4_policy.c + * + * Authors: + * Mitsuru KANDA @USAGI + * Kazunori MIYAZAWA @USAGI + * Kunihiro Ishiguro <kunihiro@ipinfusion.com> + * IPv6 support + * YOSHIFUJI Hideaki + * Split up af-specific portion + * + */ + +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/netdevice.h> +#include <net/addrconf.h> +#include <net/dst.h> +#include <net/xfrm.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <net/ip6_route.h> +#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) +#include <net/mip6.h> +#endif + +static struct xfrm_policy_afinfo xfrm6_policy_afinfo; + +static struct dst_entry *xfrm6_dst_lookup(struct net *net, int tos, + const xfrm_address_t *saddr, + const xfrm_address_t *daddr) +{ + struct flowi6 fl6; + struct dst_entry *dst; + int err; + + memset(&fl6, 0, sizeof(fl6)); + memcpy(&fl6.daddr, daddr, sizeof(fl6.daddr)); + if (saddr) + memcpy(&fl6.saddr, saddr, sizeof(fl6.saddr)); + + dst = ip6_route_output(net, NULL, &fl6); + + err = dst->error; + if (dst->error) { + dst_release(dst); + dst = ERR_PTR(err); + } + + return dst; +} + +static int xfrm6_get_saddr(struct net *net, + xfrm_address_t *saddr, xfrm_address_t *daddr) +{ + struct dst_entry *dst; + struct net_device *dev; + + dst = xfrm6_dst_lookup(net, 0, NULL, daddr); + if (IS_ERR(dst)) + return -EHOSTUNREACH; + + dev = ip6_dst_idev(dst)->dev; + ipv6_dev_get_saddr(dev_net(dev), dev, + (struct in6_addr *)&daddr->a6, 0, + (struct in6_addr *)&saddr->a6); + dst_release(dst); + return 0; +} + +static int xfrm6_get_tos(const struct flowi *fl) +{ + return 0; +} + +static int xfrm6_init_path(struct xfrm_dst *path, struct dst_entry *dst, + int nfheader_len) +{ + if (dst->ops->family == AF_INET6) { + struct rt6_info *rt = (struct rt6_info*)dst; + if (rt->rt6i_node) + path->path_cookie = rt->rt6i_node->fn_sernum; + } + + path->u.rt6.rt6i_nfheader_len = nfheader_len; + + return 0; +} + +static int xfrm6_fill_dst(struct xfrm_dst *xdst, struct net_device *dev, + const struct flowi *fl) +{ + struct rt6_info *rt = (struct rt6_info*)xdst->route; + + xdst->u.dst.dev = dev; + dev_hold(dev); + + xdst->u.rt6.rt6i_idev = in6_dev_get(dev); + if (!xdst->u.rt6.rt6i_idev) + return -ENODEV; + + xdst->u.rt6.rt6i_peer = rt->rt6i_peer; + if (rt->rt6i_peer) + atomic_inc(&rt->rt6i_peer->refcnt); + + /* Sheit... I remember I did this right. Apparently, + * it was magically lost, so this code needs audit */ + xdst->u.rt6.rt6i_flags = rt->rt6i_flags & (RTF_ANYCAST | + RTF_LOCAL); + xdst->u.rt6.rt6i_metric = rt->rt6i_metric; + xdst->u.rt6.rt6i_node = rt->rt6i_node; + if (rt->rt6i_node) + xdst->route_cookie = rt->rt6i_node->fn_sernum; + xdst->u.rt6.rt6i_gateway = rt->rt6i_gateway; + xdst->u.rt6.rt6i_dst = rt->rt6i_dst; + xdst->u.rt6.rt6i_src = rt->rt6i_src; + + return 0; +} + +static inline void +_decode_session6(struct sk_buff *skb, struct flowi *fl, int reverse) +{ + struct flowi6 *fl6 = &fl->u.ip6; + int onlyproto = 0; + u16 offset = skb_network_header_len(skb); + const struct ipv6hdr *hdr = ipv6_hdr(skb); + struct ipv6_opt_hdr *exthdr; + const unsigned char *nh = skb_network_header(skb); + u8 nexthdr = nh[IP6CB(skb)->nhoff]; + + memset(fl6, 0, sizeof(struct flowi6)); + fl6->flowi6_mark = skb->mark; + + fl6->daddr = reverse ? hdr->saddr : hdr->daddr; + fl6->saddr = reverse ? hdr->daddr : hdr->saddr; + + while (nh + offset + 1 < skb->data || + pskb_may_pull(skb, nh + offset + 1 - skb->data)) { + nh = skb_network_header(skb); + exthdr = (struct ipv6_opt_hdr *)(nh + offset); + + switch (nexthdr) { + case NEXTHDR_FRAGMENT: + onlyproto = 1; + case NEXTHDR_ROUTING: + case NEXTHDR_HOP: + case NEXTHDR_DEST: + offset += ipv6_optlen(exthdr); + nexthdr = exthdr->nexthdr; + exthdr = (struct ipv6_opt_hdr *)(nh + offset); + break; + + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + case IPPROTO_TCP: + case IPPROTO_SCTP: + case IPPROTO_DCCP: + if (!onlyproto && (nh + offset + 4 < skb->data || + pskb_may_pull(skb, nh + offset + 4 - skb->data))) { + __be16 *ports = (__be16 *)exthdr; + + fl6->fl6_sport = ports[!!reverse]; + fl6->fl6_dport = ports[!reverse]; + } + fl6->flowi6_proto = nexthdr; + return; + + case IPPROTO_ICMPV6: + if (!onlyproto && pskb_may_pull(skb, nh + offset + 2 - skb->data)) { + u8 *icmp = (u8 *)exthdr; + + fl6->fl6_icmp_type = icmp[0]; + fl6->fl6_icmp_code = icmp[1]; + } + fl6->flowi6_proto = nexthdr; + return; + +#if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) + case IPPROTO_MH: + if (!onlyproto && pskb_may_pull(skb, nh + offset + 3 - skb->data)) { + struct ip6_mh *mh; + mh = (struct ip6_mh *)exthdr; + + fl6->fl6_mh_type = mh->ip6mh_type; + } + fl6->flowi6_proto = nexthdr; + return; +#endif + + /* XXX Why are there these headers? */ + case IPPROTO_AH: + case IPPROTO_ESP: + case IPPROTO_COMP: + default: + fl6->fl6_ipsec_spi = 0; + fl6->flowi6_proto = nexthdr; + return; + } + } +} + +static inline int xfrm6_garbage_collect(struct dst_ops *ops) +{ + struct net *net = container_of(ops, struct net, xfrm.xfrm6_dst_ops); + + xfrm6_policy_afinfo.garbage_collect(net); + return dst_entries_get_fast(ops) > ops->gc_thresh * 2; +} + +static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu) +{ + struct xfrm_dst *xdst = (struct xfrm_dst *)dst; + struct dst_entry *path = xdst->route; + + path->ops->update_pmtu(path, mtu); +} + +static void xfrm6_dst_destroy(struct dst_entry *dst) +{ + struct xfrm_dst *xdst = (struct xfrm_dst *)dst; + + if (likely(xdst->u.rt6.rt6i_idev)) + in6_dev_put(xdst->u.rt6.rt6i_idev); + dst_destroy_metrics_generic(dst); + if (likely(xdst->u.rt6.rt6i_peer)) + inet_putpeer(xdst->u.rt6.rt6i_peer); + xfrm_dst_destroy(xdst); +} + +static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev, + int unregister) +{ + struct xfrm_dst *xdst; + + if (!unregister) + return; + + xdst = (struct xfrm_dst *)dst; + if (xdst->u.rt6.rt6i_idev->dev == dev) { + struct inet6_dev *loopback_idev = + in6_dev_get(dev_net(dev)->loopback_dev); + BUG_ON(!loopback_idev); + + do { + in6_dev_put(xdst->u.rt6.rt6i_idev); + xdst->u.rt6.rt6i_idev = loopback_idev; + in6_dev_hold(loopback_idev); + xdst = (struct xfrm_dst *)xdst->u.dst.child; + } while (xdst->u.dst.xfrm); + + __in6_dev_put(loopback_idev); + } + + xfrm_dst_ifdown(dst, dev); +} + +static struct dst_ops xfrm6_dst_ops = { + .family = AF_INET6, + .protocol = cpu_to_be16(ETH_P_IPV6), + .gc = xfrm6_garbage_collect, + .update_pmtu = xfrm6_update_pmtu, + .cow_metrics = dst_cow_metrics_generic, + .destroy = xfrm6_dst_destroy, + .ifdown = xfrm6_dst_ifdown, + .local_out = __ip6_local_out, + .gc_thresh = 1024, +}; + +static struct xfrm_policy_afinfo xfrm6_policy_afinfo = { + .family = AF_INET6, + .dst_ops = &xfrm6_dst_ops, + .dst_lookup = xfrm6_dst_lookup, + .get_saddr = xfrm6_get_saddr, + .decode_session = _decode_session6, + .get_tos = xfrm6_get_tos, + .init_path = xfrm6_init_path, + .fill_dst = xfrm6_fill_dst, + .blackhole_route = ip6_blackhole_route, +}; + +static int __init xfrm6_policy_init(void) +{ + return xfrm_policy_register_afinfo(&xfrm6_policy_afinfo); +} + +static void xfrm6_policy_fini(void) +{ + xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo); +} + +#ifdef CONFIG_SYSCTL +static struct ctl_table xfrm6_policy_table[] = { + { + .procname = "xfrm6_gc_thresh", + .data = &init_net.xfrm.xfrm6_dst_ops.gc_thresh, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { } +}; + +static struct ctl_table_header *sysctl_hdr; +#endif + +int __init xfrm6_init(void) +{ + int ret; + unsigned int gc_thresh; + + /* + * We need a good default value for the xfrm6 gc threshold. + * In ipv4 we set it to the route hash table size * 8, which + * is half the size of the maximaum route cache for ipv4. It + * would be good to do the same thing for v6, except the table is + * constructed differently here. Here each table for a net namespace + * can have FIB_TABLE_HASHSZ entries, so lets go with the same + * computation that we used for ipv4 here. Also, lets keep the initial + * gc_thresh to a minimum of 1024, since, the ipv6 route cache defaults + * to that as a minimum as well + */ + gc_thresh = FIB6_TABLE_HASHSZ * 8; + xfrm6_dst_ops.gc_thresh = (gc_thresh < 1024) ? 1024 : gc_thresh; + dst_entries_init(&xfrm6_dst_ops); + + ret = xfrm6_policy_init(); + if (ret) { + dst_entries_destroy(&xfrm6_dst_ops); + goto out; + } + ret = xfrm6_state_init(); + if (ret) + goto out_policy; + +#ifdef CONFIG_SYSCTL + sysctl_hdr = register_net_sysctl_table(&init_net, net_ipv6_ctl_path, + xfrm6_policy_table); +#endif +out: + return ret; +out_policy: + xfrm6_policy_fini(); + goto out; +} + +void xfrm6_fini(void) +{ +#ifdef CONFIG_SYSCTL + if (sysctl_hdr) + unregister_net_sysctl_table(sysctl_hdr); +#endif + //xfrm6_input_fini(); + xfrm6_policy_fini(); + xfrm6_state_fini(); + dst_entries_destroy(&xfrm6_dst_ops); +} |