Initial import

1 files changed, 396 insertions, 0 deletions

diff --git a/net/xfrm/xfrm_input.c b/net/xfrm/xfrm_input.c
new file mode 100644
index 000000000..b58286ecd
--- /dev/null
+++ b/net/xfrm/xfrm_input.c
@@ -0,0 +1,396 @@
+/*
+ * 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 __rcu *xfrm_input_afinfo[NPROTO];
+
+int xfrm_input_register_afinfo(struct xfrm_input_afinfo *afinfo)
+{
+	int err = 0;
+
+	if (unlikely(afinfo == NULL))
+		return -EINVAL;
+	if (unlikely(afinfo->family >= NPROTO))
+		return -EAFNOSUPPORT;
+	spin_lock_bh(&xfrm_input_afinfo_lock);
+	if (unlikely(xfrm_input_afinfo[afinfo->family] != NULL))
+		err = -ENOBUFS;
+	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(struct xfrm_input_afinfo *afinfo)
+{
+	int err = 0;
+
+	if (unlikely(afinfo == NULL))
+		return -EINVAL;
+	if (unlikely(afinfo->family >= NPROTO))
+		return -EAFNOSUPPORT;
+	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 struct xfrm_input_afinfo *xfrm_input_get_afinfo(unsigned int family)
+{
+	struct xfrm_input_afinfo *afinfo;
+
+	if (unlikely(family >= NPROTO))
+		return NULL;
+	rcu_read_lock();
+	afinfo = rcu_dereference(xfrm_input_afinfo[family]);
+	if (unlikely(!afinfo))
+		rcu_read_unlock();
+	return afinfo;
+}
+
+static void xfrm_input_put_afinfo(struct xfrm_input_afinfo *afinfo)
+{
+	rcu_read_unlock();
+}
+
+static int xfrm_rcv_cb(struct sk_buff *skb, unsigned int family, u8 protocol,
+		       int err)
+{
+	int ret;
+	struct xfrm_input_afinfo *afinfo = xfrm_input_get_afinfo(family);
+
+	if (!afinfo)
+		return -EAFNOSUPPORT;
+
+	ret = afinfo->callback(skb, protocol, err);
+	xfrm_input_put_afinfo(afinfo);
+
+	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 */
+	if (XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4) {
+		switch (family) {
+		case AF_INET:
+			mark = be32_to_cpu(XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip4->parms.i_key);
+			break;
+		case AF_INET6:
+			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_ACQ)) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMACQUIREERROR);
+			goto drop_unlock;
+		}
+
+		if (unlikely(x->km.state != XFRM_STATE_VALID)) {
+			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);
+
+		nexthdr = x->type->input(x, skb);
+
+		if (nexthdr == -EINPROGRESS)
+			return 0;
+resume:
+		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)
+				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);
+		netif_rx(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)
+{
+	secpath_cachep = kmem_cache_create("secpath_cache",
+					   sizeof(struct sec_path),
+					   0, SLAB_HWCACHE_ALIGN|SLAB_PANIC,
+					   NULL);
+}