/* * xfrm6_input.c: based on net/ipv4/xfrm4_input.c * * Authors: * Mitsuru KANDA @USAGI * Kazunori MIYAZAWA @USAGI * Kunihiro Ishiguro <kunihiro@ipinfusion.com> * YOSHIFUJI Hideaki @USAGI * IPv6 support */ #include <linux/module.h> #include <linux/string.h> #include <net/dsfield.h> #include <net/inet_ecn.h> #include <net/ip.h> #include <net/ipv6.h> #include <net/xfrm.h> static inline void ipip6_ecn_decapsulate(struct sk_buff *skb) { struct ipv6hdr *outer_iph = skb->nh.ipv6h; struct ipv6hdr *inner_iph = skb->h.ipv6h; if (INET_ECN_is_ce(ipv6_get_dsfield(outer_iph))) IP6_ECN_set_ce(inner_iph); } int xfrm6_rcv_spi(struct sk_buff **pskb, unsigned int *nhoffp, u32 spi) { struct sk_buff *skb = *pskb; int err; u32 seq; struct sec_decap_state xfrm_vec[XFRM_MAX_DEPTH]; struct xfrm_state *x; int xfrm_nr = 0; int decaps = 0; int nexthdr; unsigned int nhoff; nhoff = *nhoffp; nexthdr = skb->nh.raw[nhoff]; seq = 0; if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0) goto drop; do { struct ipv6hdr *iph = skb->nh.ipv6h; if (xfrm_nr == XFRM_MAX_DEPTH) goto drop; x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, nexthdr, AF_INET6); if (x == NULL) goto drop; spin_lock(&x->lock); if (unlikely(x->km.state != XFRM_STATE_VALID)) goto drop_unlock; if (x->props.replay_window && xfrm_replay_check(x, seq)) goto drop_unlock; if (xfrm_state_check_expire(x)) goto drop_unlock; nexthdr = x->type->input(x, &(xfrm_vec[xfrm_nr].decap), skb); if (nexthdr <= 0) goto drop_unlock; skb->nh.raw[nhoff] = nexthdr; if (x->props.replay_window) xfrm_replay_advance(x, seq); x->curlft.bytes += skb->len; x->curlft.packets++; spin_unlock(&x->lock); xfrm_vec[xfrm_nr++].xvec = x; if (x->props.mode) { /* XXX */ if (nexthdr != IPPROTO_IPV6) goto drop; if (!pskb_may_pull(skb, sizeof(struct ipv6hdr))) goto drop; if (skb_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) goto drop; if (x->props.flags & XFRM_STATE_DECAP_DSCP) ipv6_copy_dscp(skb->nh.ipv6h, skb->h.ipv6h); if (!(x->props.flags & XFRM_STATE_NOECN)) ipip6_ecn_decapsulate(skb); skb->mac.raw = memmove(skb->data - skb->mac_len, skb->mac.raw, skb->mac_len); skb->nh.raw = skb->data; decaps = 1; break; } if ((err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) < 0) goto drop; } while (!err); /* 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) goto drop; if (skb->sp) secpath_put(skb->sp); skb->sp = sp; } if (xfrm_nr + skb->sp->len > XFRM_MAX_DEPTH) goto drop; memcpy(skb->sp->x+skb->sp->len, xfrm_vec, xfrm_nr*sizeof(struct sec_decap_state)); skb->sp->len += xfrm_nr; skb->ip_summed = CHECKSUM_NONE; if (decaps) { if (!(skb->dev->flags&IFF_LOOPBACK)) { dst_release(skb->dst); skb->dst = NULL; } netif_rx(skb); return -1; } else { return 1; } drop_unlock: spin_unlock(&x->lock); xfrm_state_put(x); drop: while (--xfrm_nr >= 0) xfrm_state_put(xfrm_vec[xfrm_nr].xvec); kfree_skb(skb); return -1; } EXPORT_SYMBOL(xfrm6_rcv_spi); int xfrm6_rcv(struct sk_buff **pskb, unsigned int *nhoffp) { return xfrm6_rcv_spi(pskb, nhoffp, 0); }