| /* |
| * 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/compiler.h> |
| #include <linux/netdevice.h> |
| #include <net/addrconf.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 dst_ops xfrm6_dst_ops; |
| static struct xfrm_policy_afinfo xfrm6_policy_afinfo; |
| |
| static int xfrm6_dst_lookup(struct xfrm_dst **xdst, struct flowi *fl) |
| { |
| struct dst_entry *dst = ip6_route_output(NULL, fl); |
| int err = dst->error; |
| if (!err) |
| *xdst = (struct xfrm_dst *) dst; |
| else |
| dst_release(dst); |
| return err; |
| } |
| |
| static int xfrm6_get_saddr(xfrm_address_t *saddr, xfrm_address_t *daddr) |
| { |
| struct rt6_info *rt; |
| struct flowi fl_tunnel = { |
| .nl_u = { |
| .ip6_u = { |
| .daddr = *(struct in6_addr *)&daddr->a6, |
| }, |
| }, |
| }; |
| |
| if (!xfrm6_dst_lookup((struct xfrm_dst **)&rt, &fl_tunnel)) { |
| ipv6_get_saddr(&rt->u.dst, (struct in6_addr *)&daddr->a6, |
| (struct in6_addr *)&saddr->a6); |
| dst_release(&rt->u.dst); |
| return 0; |
| } |
| return -EHOSTUNREACH; |
| } |
| |
| static struct dst_entry * |
| __xfrm6_find_bundle(struct flowi *fl, struct xfrm_policy *policy) |
| { |
| struct dst_entry *dst; |
| |
| /* Still not clear if we should set fl->fl6_{src,dst}... */ |
| read_lock_bh(&policy->lock); |
| for (dst = policy->bundles; dst; dst = dst->next) { |
| struct xfrm_dst *xdst = (struct xfrm_dst*)dst; |
| struct in6_addr fl_dst_prefix, fl_src_prefix; |
| |
| ipv6_addr_prefix(&fl_dst_prefix, |
| &fl->fl6_dst, |
| xdst->u.rt6.rt6i_dst.plen); |
| ipv6_addr_prefix(&fl_src_prefix, |
| &fl->fl6_src, |
| xdst->u.rt6.rt6i_src.plen); |
| if (ipv6_addr_equal(&xdst->u.rt6.rt6i_dst.addr, &fl_dst_prefix) && |
| ipv6_addr_equal(&xdst->u.rt6.rt6i_src.addr, &fl_src_prefix) && |
| xfrm_bundle_ok(policy, xdst, fl, AF_INET6, |
| (xdst->u.rt6.rt6i_dst.plen != 128 || |
| xdst->u.rt6.rt6i_src.plen != 128))) { |
| dst_clone(dst); |
| break; |
| } |
| } |
| read_unlock_bh(&policy->lock); |
| return dst; |
| } |
| |
| static inline struct in6_addr* |
| __xfrm6_bundle_addr_remote(struct xfrm_state *x, struct in6_addr *addr) |
| { |
| return (x->type->remote_addr) ? |
| (struct in6_addr*)x->type->remote_addr(x, (xfrm_address_t *)addr) : |
| (struct in6_addr*)&x->id.daddr; |
| } |
| |
| static inline struct in6_addr* |
| __xfrm6_bundle_addr_local(struct xfrm_state *x, struct in6_addr *addr) |
| { |
| return (x->type->local_addr) ? |
| (struct in6_addr*)x->type->local_addr(x, (xfrm_address_t *)addr) : |
| (struct in6_addr*)&x->props.saddr; |
| } |
| |
| static inline void |
| __xfrm6_bundle_len_inc(int *len, int *nflen, struct xfrm_state *x) |
| { |
| if (x->type->flags & XFRM_TYPE_NON_FRAGMENT) |
| *nflen += x->props.header_len; |
| else |
| *len += x->props.header_len; |
| } |
| |
| static inline void |
| __xfrm6_bundle_len_dec(int *len, int *nflen, struct xfrm_state *x) |
| { |
| if (x->type->flags & XFRM_TYPE_NON_FRAGMENT) |
| *nflen -= x->props.header_len; |
| else |
| *len -= x->props.header_len; |
| } |
| |
| /* Allocate chain of dst_entry's, attach known xfrm's, calculate |
| * all the metrics... Shortly, bundle a bundle. |
| */ |
| |
| static int |
| __xfrm6_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx, |
| struct flowi *fl, struct dst_entry **dst_p) |
| { |
| struct dst_entry *dst, *dst_prev; |
| struct rt6_info *rt0 = (struct rt6_info*)(*dst_p); |
| struct rt6_info *rt = rt0; |
| struct flowi fl_tunnel = { |
| .nl_u = { |
| .ip6_u = { |
| .saddr = fl->fl6_src, |
| .daddr = fl->fl6_dst, |
| } |
| } |
| }; |
| int i; |
| int err = 0; |
| int header_len = 0; |
| int nfheader_len = 0; |
| int trailer_len = 0; |
| |
| dst = dst_prev = NULL; |
| dst_hold(&rt->u.dst); |
| |
| for (i = 0; i < nx; i++) { |
| struct dst_entry *dst1 = dst_alloc(&xfrm6_dst_ops); |
| struct xfrm_dst *xdst; |
| |
| if (unlikely(dst1 == NULL)) { |
| err = -ENOBUFS; |
| dst_release(&rt->u.dst); |
| goto error; |
| } |
| |
| if (!dst) |
| dst = dst1; |
| else { |
| dst_prev->child = dst1; |
| dst1->flags |= DST_NOHASH; |
| dst_clone(dst1); |
| } |
| |
| xdst = (struct xfrm_dst *)dst1; |
| xdst->route = &rt->u.dst; |
| xdst->genid = xfrm[i]->genid; |
| if (rt->rt6i_node) |
| xdst->route_cookie = rt->rt6i_node->fn_sernum; |
| |
| dst1->next = dst_prev; |
| dst_prev = dst1; |
| |
| __xfrm6_bundle_len_inc(&header_len, &nfheader_len, xfrm[i]); |
| trailer_len += xfrm[i]->props.trailer_len; |
| |
| if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) { |
| unsigned short encap_family = xfrm[i]->props.family; |
| switch(encap_family) { |
| case AF_INET: |
| fl_tunnel.fl4_dst = xfrm[i]->id.daddr.a4; |
| fl_tunnel.fl4_src = xfrm[i]->props.saddr.a4; |
| break; |
| case AF_INET6: |
| ipv6_addr_copy(&fl_tunnel.fl6_dst, __xfrm6_bundle_addr_remote(xfrm[i], &fl->fl6_dst)); |
| |
| ipv6_addr_copy(&fl_tunnel.fl6_src, __xfrm6_bundle_addr_local(xfrm[i], &fl->fl6_src)); |
| break; |
| default: |
| BUG_ON(1); |
| } |
| |
| err = xfrm_dst_lookup((struct xfrm_dst **) &rt, |
| &fl_tunnel, encap_family); |
| if (err) |
| goto error; |
| } else |
| dst_hold(&rt->u.dst); |
| } |
| |
| dst_prev->child = &rt->u.dst; |
| dst->path = &rt->u.dst; |
| if (rt->rt6i_node) |
| ((struct xfrm_dst *)dst)->path_cookie = rt->rt6i_node->fn_sernum; |
| |
| *dst_p = dst; |
| dst = dst_prev; |
| |
| dst_prev = *dst_p; |
| i = 0; |
| for (; dst_prev != &rt->u.dst; dst_prev = dst_prev->child) { |
| struct xfrm_dst *x = (struct xfrm_dst*)dst_prev; |
| struct xfrm_state_afinfo *afinfo; |
| |
| dst_prev->xfrm = xfrm[i++]; |
| dst_prev->dev = rt->u.dst.dev; |
| if (rt->u.dst.dev) |
| dev_hold(rt->u.dst.dev); |
| dst_prev->obsolete = -1; |
| dst_prev->flags |= DST_HOST; |
| dst_prev->lastuse = jiffies; |
| dst_prev->header_len = header_len; |
| dst_prev->nfheader_len = nfheader_len; |
| dst_prev->trailer_len = trailer_len; |
| memcpy(&dst_prev->metrics, &x->route->metrics, sizeof(dst_prev->metrics)); |
| |
| /* Copy neighbour for reachability confirmation */ |
| dst_prev->neighbour = neigh_clone(rt->u.dst.neighbour); |
| dst_prev->input = rt->u.dst.input; |
| /* XXX: When IPv4 is implemented as module and can be unloaded, |
| * we should manage reference to xfrm4_output in afinfo->output. |
| * Miyazawa |
| */ |
| afinfo = xfrm_state_get_afinfo(dst_prev->xfrm->props.family); |
| if (!afinfo) { |
| dst = *dst_p; |
| goto error; |
| } |
| |
| dst_prev->output = afinfo->output; |
| xfrm_state_put_afinfo(afinfo); |
| /* Sheit... I remember I did this right. Apparently, |
| * it was magically lost, so this code needs audit */ |
| x->u.rt6.rt6i_flags = rt0->rt6i_flags&(RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL); |
| x->u.rt6.rt6i_metric = rt0->rt6i_metric; |
| x->u.rt6.rt6i_node = rt0->rt6i_node; |
| x->u.rt6.rt6i_gateway = rt0->rt6i_gateway; |
| memcpy(&x->u.rt6.rt6i_gateway, &rt0->rt6i_gateway, sizeof(x->u.rt6.rt6i_gateway)); |
| x->u.rt6.rt6i_dst = rt0->rt6i_dst; |
| x->u.rt6.rt6i_src = rt0->rt6i_src; |
| x->u.rt6.rt6i_idev = rt0->rt6i_idev; |
| in6_dev_hold(rt0->rt6i_idev); |
| __xfrm6_bundle_len_dec(&header_len, &nfheader_len, x->u.dst.xfrm); |
| trailer_len -= x->u.dst.xfrm->props.trailer_len; |
| } |
| |
| xfrm_init_pmtu(dst); |
| return 0; |
| |
| error: |
| if (dst) |
| dst_free(dst); |
| return err; |
| } |
| |
| static inline void |
| _decode_session6(struct sk_buff *skb, struct flowi *fl) |
| { |
| u16 offset = skb_network_header_len(skb); |
| 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(fl, 0, sizeof(struct flowi)); |
| ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr); |
| ipv6_addr_copy(&fl->fl6_src, &hdr->saddr); |
| |
| while (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_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 (pskb_may_pull(skb, nh + offset + 4 - skb->data)) { |
| __be16 *ports = (__be16 *)exthdr; |
| |
| fl->fl_ip_sport = ports[0]; |
| fl->fl_ip_dport = ports[1]; |
| } |
| fl->proto = nexthdr; |
| return; |
| |
| case IPPROTO_ICMPV6: |
| if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) { |
| u8 *icmp = (u8 *)exthdr; |
| |
| fl->fl_icmp_type = icmp[0]; |
| fl->fl_icmp_code = icmp[1]; |
| } |
| fl->proto = nexthdr; |
| return; |
| |
| #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE) |
| case IPPROTO_MH: |
| if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) { |
| struct ip6_mh *mh; |
| mh = (struct ip6_mh *)exthdr; |
| |
| fl->fl_mh_type = mh->ip6mh_type; |
| } |
| fl->proto = nexthdr; |
| return; |
| #endif |
| |
| /* XXX Why are there these headers? */ |
| case IPPROTO_AH: |
| case IPPROTO_ESP: |
| case IPPROTO_COMP: |
| default: |
| fl->fl_ipsec_spi = 0; |
| fl->proto = nexthdr; |
| return; |
| } |
| } |
| } |
| |
| static inline int xfrm6_garbage_collect(void) |
| { |
| xfrm6_policy_afinfo.garbage_collect(); |
| return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_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); |
| 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(init_net.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 = __constant_htons(ETH_P_IPV6), |
| .gc = xfrm6_garbage_collect, |
| .update_pmtu = xfrm6_update_pmtu, |
| .destroy = xfrm6_dst_destroy, |
| .ifdown = xfrm6_dst_ifdown, |
| .gc_thresh = 1024, |
| .entry_size = sizeof(struct xfrm_dst), |
| }; |
| |
| 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, |
| .find_bundle = __xfrm6_find_bundle, |
| .bundle_create = __xfrm6_bundle_create, |
| .decode_session = _decode_session6, |
| }; |
| |
| static void __init xfrm6_policy_init(void) |
| { |
| xfrm_policy_register_afinfo(&xfrm6_policy_afinfo); |
| } |
| |
| static void xfrm6_policy_fini(void) |
| { |
| xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo); |
| } |
| |
| void __init xfrm6_init(void) |
| { |
| xfrm6_policy_init(); |
| xfrm6_state_init(); |
| } |
| |
| void xfrm6_fini(void) |
| { |
| //xfrm6_input_fini(); |
| xfrm6_policy_fini(); |
| xfrm6_state_fini(); |
| } |