| /* |
| * xfrm_input.c |
| * |
| * Changes: |
| * YOSHIFUJI Hideaki @USAGI |
| * Split up af-specific portion |
| * |
| */ |
| |
| #include <linux/slab.h> |
| #include <linux/module.h> |
| #include <linux/netdevice.h> |
| #include <net/dst.h> |
| #include <net/ip.h> |
| #include <net/xfrm.h> |
| #include <net/ip_tunnels.h> |
| #include <net/ip6_tunnel.h> |
| |
| static struct kmem_cache *secpath_cachep __read_mostly; |
| |
| static DEFINE_SPINLOCK(xfrm_input_afinfo_lock); |
| static struct xfrm_input_afinfo const __rcu *xfrm_input_afinfo[AF_INET6 + 1]; |
| |
| static struct gro_cells gro_cells; |
| static struct net_device xfrm_napi_dev; |
| |
| int xfrm_input_register_afinfo(const struct xfrm_input_afinfo *afinfo) |
| { |
| int err = 0; |
| |
| if (WARN_ON(afinfo->family >= ARRAY_SIZE(xfrm_input_afinfo))) |
| return -EAFNOSUPPORT; |
| |
| spin_lock_bh(&xfrm_input_afinfo_lock); |
| if (unlikely(xfrm_input_afinfo[afinfo->family] != NULL)) |
| err = -EEXIST; |
| else |
| rcu_assign_pointer(xfrm_input_afinfo[afinfo->family], afinfo); |
| spin_unlock_bh(&xfrm_input_afinfo_lock); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_input_register_afinfo); |
| |
| int xfrm_input_unregister_afinfo(const struct xfrm_input_afinfo *afinfo) |
| { |
| int err = 0; |
| |
| spin_lock_bh(&xfrm_input_afinfo_lock); |
| if (likely(xfrm_input_afinfo[afinfo->family] != NULL)) { |
| if (unlikely(xfrm_input_afinfo[afinfo->family] != afinfo)) |
| err = -EINVAL; |
| else |
| RCU_INIT_POINTER(xfrm_input_afinfo[afinfo->family], NULL); |
| } |
| spin_unlock_bh(&xfrm_input_afinfo_lock); |
| synchronize_rcu(); |
| return err; |
| } |
| EXPORT_SYMBOL(xfrm_input_unregister_afinfo); |
| |
| static const struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family) |
| { |
| const struct xfrm_input_afinfo *afinfo; |
| |
| if (WARN_ON_ONCE(family >= ARRAY_SIZE(xfrm_input_afinfo))) |
| return NULL; |
| |
| rcu_read_lock(); |
| afinfo = rcu_dereference(xfrm_input_afinfo[family]); |
| if (unlikely(!afinfo)) |
| rcu_read_unlock(); |
| return afinfo; |
| } |
| |
| static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol, |
| int err) |
| { |
| int ret; |
| const struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family); |
| |
| if (!afinfo) |
| return -EAFNOSUPPORT; |
| |
| ret = afinfo->callback(skb, protocol, err); |
| rcu_read_unlock(); |
| |
| return ret; |
| } |
| |
| void __secpath_destroy(struct sec_path *sp) |
| { |
| int i; |
| for (i = 0; i < sp->len; i++) |
| xfrm_state_put(sp->xvec[i]); |
| kmem_cache_free(secpath_cachep, sp); |
| } |
| EXPORT_SYMBOL(__secpath_destroy); |
| |
| struct sec_path *secpath_dup(struct sec_path *src) |
| { |
| struct sec_path *sp; |
| |
| sp = kmem_cache_alloc(secpath_cachep, GFP_ATOMIC); |
| if (!sp) |
| return NULL; |
| |
| sp->len = 0; |
| if (src) { |
| int i; |
| |
| memcpy(sp, src, sizeof(*sp)); |
| for (i = 0; i < sp->len; i++) |
| xfrm_state_hold(sp->xvec[i]); |
| } |
| atomic_set(&sp->refcnt, 1); |
| return sp; |
| } |
| EXPORT_SYMBOL(secpath_dup); |
| |
| /* Fetch spi and seq from ipsec header */ |
| |
| int xfrm_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq) |
| { |
| int offset, offset_seq; |
| int hlen; |
| |
| switch (nexthdr) { |
| case IPPROTO_AH: |
| hlen = sizeof(struct ip_auth_hdr); |
| offset = offsetof(struct ip_auth_hdr, spi); |
| offset_seq = offsetof(struct ip_auth_hdr, seq_no); |
| break; |
| case IPPROTO_ESP: |
| hlen = sizeof(struct ip_esp_hdr); |
| offset = offsetof(struct ip_esp_hdr, spi); |
| offset_seq = offsetof(struct ip_esp_hdr, seq_no); |
| break; |
| case IPPROTO_COMP: |
| if (!pskb_may_pull(skb, sizeof(struct ip_comp_hdr))) |
| return -EINVAL; |
| *spi = htonl(ntohs(*(__be16 *)(skb_transport_header(skb) + 2))); |
| *seq = 0; |
| return 0; |
| default: |
| return 1; |
| } |
| |
| if (!pskb_may_pull(skb, hlen)) |
| return -EINVAL; |
| |
| *spi = *(__be32 *)(skb_transport_header(skb) + offset); |
| *seq = *(__be32 *)(skb_transport_header(skb) + offset_seq); |
| return 0; |
| } |
| |
| int xfrm_prepare_input(struct xfrm_state *x, struct sk_buff *skb) |
| { |
| struct xfrm_mode *inner_mode = x->inner_mode; |
| int err; |
| |
| err = x->outer_mode->afinfo->extract_input(x, skb); |
| if (err) |
| return err; |
| |
| if (x->sel.family == AF_UNSPEC) { |
| inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); |
| if (inner_mode == NULL) |
| return -EAFNOSUPPORT; |
| } |
| |
| skb->protocol = inner_mode->afinfo->eth_proto; |
| return inner_mode->input2(x, skb); |
| } |
| EXPORT_SYMBOL(xfrm_prepare_input); |
| |
| int xfrm_input(struct sk_buff *skb, int nexthdr, __be32 spi, int encap_type) |
| { |
| struct net *net = dev_net(skb->dev); |
| int err; |
| __be32 seq; |
| __be32 seq_hi; |
| struct xfrm_state *x = NULL; |
| xfrm_address_t *daddr; |
| struct xfrm_mode *inner_mode; |
| u32 mark = skb->mark; |
| unsigned int family; |
| int decaps = 0; |
| int async = 0; |
| |
| /* A negative encap_type indicates async resumption. */ |
| if (encap_type < 0) { |
| async = 1; |
| x = xfrm_input_state(skb); |
| seq = XFRM_SKB_CB(skb)->seq.input.low; |
| family = x->outer_mode->afinfo->family; |
| goto resume; |
| } |
| |
| daddr = (xfrm_address_t *)(skb_network_header(skb) + |
| XFRM_SPI_SKB_CB(skb)->daddroff); |
| family = XFRM_SPI_SKB_CB(skb)->family; |
| |
| /* if tunnel is present override skb->mark value with tunnel i_key */ |
| switch (family) { |
| case AF_INET: |
| if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4) |
| mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key); |
| break; |
| case AF_INET6: |
| if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6) |
| mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6->parms.i_key); |
| break; |
| } |
| |
| /* Allocate new secpath or COW existing one. */ |
| if (!skb->sp || atomic_read(&skb->sp->refcnt) != 1) { |
| struct sec_path *sp; |
| |
| sp = secpath_dup(skb->sp); |
| if (!sp) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR); |
| goto drop; |
| } |
| if (skb->sp) |
| secpath_put(skb->sp); |
| skb->sp = sp; |
| } |
| |
| seq = 0; |
| if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); |
| goto drop; |
| } |
| |
| do { |
| if (skb->sp->len == XFRM_MAX_DEPTH) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR); |
| goto drop; |
| } |
| |
| x = xfrm_state_lookup(net, mark, daddr, spi, nexthdr, family); |
| if (x == NULL) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES); |
| xfrm_audit_state_notfound(skb, family, spi, seq); |
| goto drop; |
| } |
| |
| skb->sp->xvec[skb->sp->len++] = x; |
| |
| spin_lock(&x->lock); |
| |
| if (unlikely(x->km.state != XFRM_STATE_VALID)) { |
| if (x->km.state == XFRM_STATE_ACQ) |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR); |
| else |
| XFRM_INC_STATS(net, |
| LINUX_MIB_XFRMINSTATEINVALID); |
| goto drop_unlock; |
| } |
| |
| if ((x->encap ? x->encap->encap_type : 0) != encap_type) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMISMATCH); |
| goto drop_unlock; |
| } |
| |
| if (x->repl->check(x, skb, seq)) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR); |
| goto drop_unlock; |
| } |
| |
| if (xfrm_state_check_expire(x)) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEEXPIRED); |
| goto drop_unlock; |
| } |
| |
| spin_unlock(&x->lock); |
| |
| if (xfrm_tunnel_check(skb, x, family)) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); |
| goto drop; |
| } |
| |
| seq_hi = htonl(xfrm_replay_seqhi(x, seq)); |
| |
| XFRM_SKB_CB(skb)->seq.input.low = seq; |
| XFRM_SKB_CB(skb)->seq.input.hi = seq_hi; |
| |
| skb_dst_force(skb); |
| dev_hold(skb->dev); |
| |
| nexthdr = x->type->input(x, skb); |
| |
| if (nexthdr == -EINPROGRESS) |
| return 0; |
| resume: |
| dev_put(skb->dev); |
| |
| spin_lock(&x->lock); |
| if (nexthdr <= 0) { |
| if (nexthdr == -EBADMSG) { |
| xfrm_audit_state_icvfail(x, skb, |
| x->type->proto); |
| x->stats.integrity_failed++; |
| } |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEPROTOERROR); |
| goto drop_unlock; |
| } |
| |
| /* only the first xfrm gets the encap type */ |
| encap_type = 0; |
| |
| if (async && x->repl->recheck(x, skb, seq)) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATESEQERROR); |
| goto drop_unlock; |
| } |
| |
| x->repl->advance(x, seq); |
| |
| x->curlft.bytes += skb->len; |
| x->curlft.packets++; |
| |
| spin_unlock(&x->lock); |
| |
| XFRM_MODE_SKB_CB(skb)->protocol = nexthdr; |
| |
| inner_mode = x->inner_mode; |
| |
| if (x->sel.family == AF_UNSPEC) { |
| inner_mode = xfrm_ip2inner_mode(x, XFRM_MODE_SKB_CB(skb)->protocol); |
| if (inner_mode == NULL) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); |
| goto drop; |
| } |
| } |
| |
| if (inner_mode->input(x, skb)) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINSTATEMODEERROR); |
| goto drop; |
| } |
| |
| if (x->outer_mode->flags & XFRM_MODE_FLAG_TUNNEL) { |
| decaps = 1; |
| break; |
| } |
| |
| /* |
| * We need the inner address. However, we only get here for |
| * transport mode so the outer address is identical. |
| */ |
| daddr = &x->id.daddr; |
| family = x->outer_mode->afinfo->family; |
| |
| err = xfrm_parse_spi(skb, nexthdr, &spi, &seq); |
| if (err < 0) { |
| XFRM_INC_STATS(net, LINUX_MIB_XFRMINHDRERROR); |
| goto drop; |
| } |
| } while (!err); |
| |
| err = xfrm_rcv_cb(skb, family, x->type->proto, 0); |
| if (err) |
| goto drop; |
| |
| nf_reset(skb); |
| |
| if (decaps) { |
| skb_dst_drop(skb); |
| gro_cells_receive(&gro_cells, skb); |
| return 0; |
| } else { |
| return x->inner_mode->afinfo->transport_finish(skb, async); |
| } |
| |
| drop_unlock: |
| spin_unlock(&x->lock); |
| drop: |
| xfrm_rcv_cb(skb, family, x && x->type ? x->type->proto : nexthdr, -1); |
| kfree_skb(skb); |
| return 0; |
| } |
| EXPORT_SYMBOL(xfrm_input); |
| |
| int xfrm_input_resume(struct sk_buff *skb, int nexthdr) |
| { |
| return xfrm_input(skb, nexthdr, 0, -1); |
| } |
| EXPORT_SYMBOL(xfrm_input_resume); |
| |
| void __init xfrm_input_init(void) |
| { |
| int err; |
| |
| init_dummy_netdev(&xfrm_napi_dev); |
| err = gro_cells_init(&gro_cells, &xfrm_napi_dev); |
| if (err) |
| gro_cells.cells = NULL; |
| |
| secpath_cachep = kmem_cache_create("secpath_cache", |
| sizeof(struct sec_path), |
| 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, |
| NULL); |
| } |