summaryrefslogtreecommitdiffstats
path: root/net/ipv6/xfrm6_input.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/ipv6/xfrm6_input.c')
-rw-r--r--net/ipv6/xfrm6_input.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
new file mode 100644
index 0000000000..4156387248
--- /dev/null
+++ b/net/ipv6/xfrm6_input.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * 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 <linux/netfilter.h>
+#include <linux/netfilter_ipv6.h>
+#include <net/ipv6.h>
+#include <net/xfrm.h>
+
+int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi,
+ struct ip6_tnl *t)
+{
+ XFRM_TUNNEL_SKB_CB(skb)->tunnel.ip6 = t;
+ XFRM_SPI_SKB_CB(skb)->family = AF_INET6;
+ XFRM_SPI_SKB_CB(skb)->daddroff = offsetof(struct ipv6hdr, daddr);
+ return xfrm_input(skb, nexthdr, spi, 0);
+}
+EXPORT_SYMBOL(xfrm6_rcv_spi);
+
+static int xfrm6_transport_finish2(struct net *net, struct sock *sk,
+ struct sk_buff *skb)
+{
+ if (xfrm_trans_queue(skb, ip6_rcv_finish)) {
+ kfree_skb(skb);
+ return NET_RX_DROP;
+ }
+
+ return 0;
+}
+
+int xfrm6_transport_finish(struct sk_buff *skb, int async)
+{
+ struct xfrm_offload *xo = xfrm_offload(skb);
+ int nhlen = skb->data - skb_network_header(skb);
+
+ skb_network_header(skb)[IP6CB(skb)->nhoff] =
+ XFRM_MODE_SKB_CB(skb)->protocol;
+
+#ifndef CONFIG_NETFILTER
+ if (!async)
+ return 1;
+#endif
+
+ __skb_push(skb, nhlen);
+ ipv6_hdr(skb)->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+ skb_postpush_rcsum(skb, skb_network_header(skb), nhlen);
+
+ if (xo && (xo->flags & XFRM_GRO)) {
+ skb_mac_header_rebuild(skb);
+ skb_reset_transport_header(skb);
+ return 0;
+ }
+
+ NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING,
+ dev_net(skb->dev), NULL, skb, skb->dev, NULL,
+ xfrm6_transport_finish2);
+ return 0;
+}
+
+/* If it's a keepalive packet, then just eat it.
+ * If it's an encapsulated packet, then pass it to the
+ * IPsec xfrm input.
+ * Returns 0 if skb passed to xfrm or was dropped.
+ * Returns >0 if skb should be passed to UDP.
+ * Returns <0 if skb should be resubmitted (-ret is protocol)
+ */
+int xfrm6_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
+{
+ struct udp_sock *up = udp_sk(sk);
+ struct udphdr *uh;
+ struct ipv6hdr *ip6h;
+ int len;
+ int ip6hlen = sizeof(struct ipv6hdr);
+ __u8 *udpdata;
+ __be32 *udpdata32;
+ u16 encap_type;
+
+ if (skb->protocol == htons(ETH_P_IP))
+ return xfrm4_udp_encap_rcv(sk, skb);
+
+ encap_type = READ_ONCE(up->encap_type);
+ /* if this is not encapsulated socket, then just return now */
+ if (!encap_type)
+ return 1;
+
+ /* If this is a paged skb, make sure we pull up
+ * whatever data we need to look at. */
+ len = skb->len - sizeof(struct udphdr);
+ if (!pskb_may_pull(skb, sizeof(struct udphdr) + min(len, 8)))
+ return 1;
+
+ /* Now we can get the pointers */
+ uh = udp_hdr(skb);
+ udpdata = (__u8 *)uh + sizeof(struct udphdr);
+ udpdata32 = (__be32 *)udpdata;
+
+ switch (encap_type) {
+ default:
+ case UDP_ENCAP_ESPINUDP:
+ /* Check if this is a keepalive packet. If so, eat it. */
+ if (len == 1 && udpdata[0] == 0xff) {
+ goto drop;
+ } else if (len > sizeof(struct ip_esp_hdr) && udpdata32[0] != 0) {
+ /* ESP Packet without Non-ESP header */
+ len = sizeof(struct udphdr);
+ } else
+ /* Must be an IKE packet.. pass it through */
+ return 1;
+ break;
+ case UDP_ENCAP_ESPINUDP_NON_IKE:
+ /* Check if this is a keepalive packet. If so, eat it. */
+ if (len == 1 && udpdata[0] == 0xff) {
+ goto drop;
+ } else if (len > 2 * sizeof(u32) + sizeof(struct ip_esp_hdr) &&
+ udpdata32[0] == 0 && udpdata32[1] == 0) {
+
+ /* ESP Packet with Non-IKE marker */
+ len = sizeof(struct udphdr) + 2 * sizeof(u32);
+ } else
+ /* Must be an IKE packet.. pass it through */
+ return 1;
+ break;
+ }
+
+ /* At this point we are sure that this is an ESPinUDP packet,
+ * so we need to remove 'len' bytes from the packet (the UDP
+ * header and optional ESP marker bytes) and then modify the
+ * protocol to ESP, and then call into the transform receiver.
+ */
+ if (skb_unclone(skb, GFP_ATOMIC))
+ goto drop;
+
+ /* Now we can update and verify the packet length... */
+ ip6h = ipv6_hdr(skb);
+ ip6h->payload_len = htons(ntohs(ip6h->payload_len) - len);
+ if (skb->len < ip6hlen + len) {
+ /* packet is too small!?! */
+ goto drop;
+ }
+
+ /* pull the data buffer up to the ESP header and set the
+ * transport header to point to ESP. Keep UDP on the stack
+ * for later.
+ */
+ __skb_pull(skb, len);
+ skb_reset_transport_header(skb);
+
+ /* process ESP */
+ return xfrm6_rcv_encap(skb, IPPROTO_ESP, 0, encap_type);
+
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+
+int xfrm6_rcv_tnl(struct sk_buff *skb, struct ip6_tnl *t)
+{
+ return xfrm6_rcv_spi(skb, skb_network_header(skb)[IP6CB(skb)->nhoff],
+ 0, t);
+}
+EXPORT_SYMBOL(xfrm6_rcv_tnl);
+
+int xfrm6_rcv(struct sk_buff *skb)
+{
+ return xfrm6_rcv_tnl(skb, NULL);
+}
+EXPORT_SYMBOL(xfrm6_rcv);
+int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,
+ xfrm_address_t *saddr, u8 proto)
+{
+ struct net *net = dev_net(skb->dev);
+ struct xfrm_state *x = NULL;
+ struct sec_path *sp;
+ int i = 0;
+
+ sp = secpath_set(skb);
+ if (!sp) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMINERROR);
+ goto drop;
+ }
+
+ if (1 + sp->len == XFRM_MAX_DEPTH) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMINBUFFERERROR);
+ goto drop;
+ }
+
+ for (i = 0; i < 3; i++) {
+ xfrm_address_t *dst, *src;
+
+ switch (i) {
+ case 0:
+ dst = daddr;
+ src = saddr;
+ break;
+ case 1:
+ /* lookup state with wild-card source address */
+ dst = daddr;
+ src = (xfrm_address_t *)&in6addr_any;
+ break;
+ default:
+ /* lookup state with wild-card addresses */
+ dst = (xfrm_address_t *)&in6addr_any;
+ src = (xfrm_address_t *)&in6addr_any;
+ break;
+ }
+
+ x = xfrm_state_lookup_byaddr(net, skb->mark, dst, src, proto, AF_INET6);
+ if (!x)
+ continue;
+
+ spin_lock(&x->lock);
+
+ if ((!i || (x->props.flags & XFRM_STATE_WILDRECV)) &&
+ likely(x->km.state == XFRM_STATE_VALID) &&
+ !xfrm_state_check_expire(x)) {
+ spin_unlock(&x->lock);
+ if (x->type->input(x, skb) > 0) {
+ /* found a valid state */
+ break;
+ }
+ } else
+ spin_unlock(&x->lock);
+
+ xfrm_state_put(x);
+ x = NULL;
+ }
+
+ if (!x) {
+ XFRM_INC_STATS(net, LINUX_MIB_XFRMINNOSTATES);
+ xfrm_audit_state_notfound_simple(skb, AF_INET6);
+ goto drop;
+ }
+
+ sp->xvec[sp->len++] = x;
+
+ spin_lock(&x->lock);
+
+ x->curlft.bytes += skb->len;
+ x->curlft.packets++;
+
+ spin_unlock(&x->lock);
+
+ return 1;
+
+drop:
+ return -1;
+}
+EXPORT_SYMBOL(xfrm6_input_addr);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 06:15:09 +0000