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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 13:31:22 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-07-12 13:31:22 -0700
commite1bd2ac5a6b7a8b625e40c9e9f8b6dea4cf22f85 (patch)
tree9366e9fb481da2c7195ca3f2bafeffebbf001363 /net/ipv4/xfrm4_input.c
parent0b9062f6b57a87f22309c6b920a51aaa66ce2a13 (diff)
parent15028aad00ddf241581fbe74a02ec89cbb28d35d (diff)
Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6: (183 commits) [TG3]: Update version to 3.78. [TG3]: Add missing NVRAM strapping. [TG3]: Enable auto MDI. [TG3]: Fix the polarity bit. [TG3]: Fix irq_sync race condition. [NET_SCHED]: ematch: module autoloading [TCP]: tcp probe wraparound handling and other changes [RTNETLINK]: rtnl_link: allow specifying initial device address [RTNETLINK]: rtnl_link API simplification [VLAN]: Fix MAC address handling [ETH]: Validate address in eth_mac_addr [NET]: Fix races in net_rx_action vs netpoll. [AF_UNIX]: Rewrite garbage collector, fixes race. [NETFILTER]: {ip, nf}_conntrack_sctp: fix remotely triggerable NULL ptr dereference (CVE-2007-2876) [NET]: Make all initialized struct seq_operations const. [UDP]: Fix length check. [IPV6]: Remove unneeded pointer idev from addrconf_cleanup(). [DECNET]: Another unnecessary net/tcp.h inclusion in net/dn.h [IPV6]: Make IPV6_{RECV,2292}RTHDR boolean options. [IPV6]: Do not send RH0 anymore. ... Fixed up trivial conflict in Documentation/feature-removal-schedule.txt manually. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'net/ipv4/xfrm4_input.c')
-rw-r--r--net/ipv4/xfrm4_input.c114
1 files changed, 106 insertions, 8 deletions
diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index fa1902dc81b..2fa10824541 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -16,13 +16,6 @@
#include <net/ip.h>
#include <net/xfrm.h>
-int xfrm4_rcv(struct sk_buff *skb)
-{
- return xfrm4_rcv_encap(skb, 0);
-}
-
-EXPORT_SYMBOL(xfrm4_rcv);
-
static int xfrm4_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32 *seq)
{
switch (nexthdr) {
@@ -53,7 +46,7 @@ drop:
}
#endif
-int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
+static int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
{
__be32 spi, seq;
struct xfrm_state *xfrm_vec[XFRM_MAX_DEPTH];
@@ -167,3 +160,108 @@ drop:
kfree_skb(skb);
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 xfrm4_udp_encap_rcv(struct sock *sk, struct sk_buff *skb)
+{
+ struct udp_sock *up = udp_sk(sk);
+ struct udphdr *uh;
+ struct iphdr *iph;
+ int iphlen, len;
+ int ret;
+
+ __u8 *udpdata;
+ __be32 *udpdata32;
+ __u16 encap_type = 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_cloned(skb) && pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+ goto drop;
+
+ /* Now we can update and verify the packet length... */
+ iph = ip_hdr(skb);
+ iphlen = iph->ihl << 2;
+ iph->tot_len = htons(ntohs(iph->tot_len) - len);
+ if (skb->len < iphlen + 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);
+
+ /* modify the protocol (it's ESP!) */
+ iph->protocol = IPPROTO_ESP;
+
+ /* process ESP */
+ ret = xfrm4_rcv_encap(skb, encap_type);
+ return ret;
+
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+
+int xfrm4_rcv(struct sk_buff *skb)
+{
+ return xfrm4_rcv_encap(skb, 0);
+}
+
+EXPORT_SYMBOL(xfrm4_rcv);