[IPSEC] xfrm: Abstract out encapsulation modes
This patch adds the structure xfrm_mode. It is meant to represent
the operations carried out by transport/tunnel modes.
By doing this we allow additional encapsulation modes to be added
without clogging up the xfrm_input/xfrm_output paths.
Candidate modes include 4-to-6 tunnel mode, 6-to-4 tunnel mode, and
BEET modes.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index 6b42cc4..46a15c7 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -118,6 +118,10 @@
XFRM_SHARE_UNIQUE /* Use once */
};
+#define XFRM_MODE_TRANSPORT 0
+#define XFRM_MODE_TUNNEL 1
+#define XFRM_MODE_MAX 2
+
/* Netlink configuration messages. */
enum {
XFRM_MSG_BASE = 0x10,
diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index ed7c974..ed5bb34 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -20,6 +20,8 @@
#include <net/ip6_fib.h>
#define XFRM_ALIGN8(len) (((len) + 7) & ~7)
+#define MODULE_ALIAS_XFRM_MODE(family, encap) \
+ MODULE_ALIAS("xfrm-mode-" __stringify(family) "-" __stringify(encap))
extern struct sock *xfrm_nl;
extern u32 sysctl_xfrm_aevent_etime;
@@ -164,6 +166,7 @@
/* Reference to data common to all the instances of this
* transformer. */
struct xfrm_type *type;
+ struct xfrm_mode *mode;
/* Security context */
struct xfrm_sec_ctx *security;
@@ -205,6 +208,7 @@
struct xfrm_policy_afinfo {
unsigned short family;
struct xfrm_type *type_map[256];
+ struct xfrm_mode *mode_map[XFRM_MODE_MAX];
struct dst_ops *dst_ops;
void (*garbage_collect)(void);
int (*dst_lookup)(struct xfrm_dst **dst, struct flowi *fl);
@@ -267,6 +271,19 @@
extern struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family);
extern void xfrm_put_type(struct xfrm_type *type);
+struct xfrm_mode {
+ int (*input)(struct xfrm_state *x, struct sk_buff *skb);
+ int (*output)(struct sk_buff *skb);
+
+ struct module *owner;
+ unsigned int encap;
+};
+
+extern int xfrm_register_mode(struct xfrm_mode *mode, int family);
+extern int xfrm_unregister_mode(struct xfrm_mode *mode, int family);
+extern struct xfrm_mode *xfrm_get_mode(unsigned int encap, int family);
+extern void xfrm_put_mode(struct xfrm_mode *mode);
+
struct xfrm_tmpl
{
/* id in template is interpreted as:
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index e40f753..35eb70b 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -414,6 +414,24 @@
tristate
default n
+config INET_XFRM_MODE_TRANSPORT
+ tristate "IP: IPsec transport mode"
+ default y
+ select XFRM
+ ---help---
+ Support for IPsec transport mode.
+
+ If unsure, say Y.
+
+config INET_XFRM_MODE_TUNNEL
+ tristate "IP: IPsec tunnel mode"
+ default y
+ select XFRM
+ ---help---
+ Support for IPsec tunnel mode.
+
+ If unsure, say Y.
+
config INET_DIAG
tristate "INET: socket monitoring interface"
default y
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 9ef50a0..4cc9448 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -24,6 +24,8 @@
obj-$(CONFIG_INET_IPCOMP) += ipcomp.o
obj-$(CONFIG_INET_XFRM_TUNNEL) += xfrm4_tunnel.o
obj-$(CONFIG_INET_TUNNEL) += tunnel4.o
+obj-$(CONFIG_INET_XFRM_MODE_TRANSPORT) += xfrm4_mode_transport.o
+obj-$(CONFIG_INET_XFRM_MODE_TUNNEL) += xfrm4_mode_tunnel.o
obj-$(CONFIG_IP_PNP) += ipconfig.o
obj-$(CONFIG_IP_ROUTE_MULTIPATH_RR) += multipath_rr.o
obj-$(CONFIG_IP_ROUTE_MULTIPATH_RANDOM) += multipath_random.o
diff --git a/net/ipv4/xfrm4_input.c b/net/ipv4/xfrm4_input.c
index 3e174c8..817ed84 100644
--- a/net/ipv4/xfrm4_input.c
+++ b/net/ipv4/xfrm4_input.c
@@ -13,7 +13,6 @@
#include <linux/string.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv4.h>
-#include <net/inet_ecn.h>
#include <net/ip.h>
#include <net/xfrm.h>
@@ -24,15 +23,6 @@
EXPORT_SYMBOL(xfrm4_rcv);
-static inline void ipip_ecn_decapsulate(struct sk_buff *skb)
-{
- struct iphdr *outer_iph = skb->nh.iph;
- struct iphdr *inner_iph = skb->h.ipiph;
-
- if (INET_ECN_is_ce(outer_iph->tos))
- IP_ECN_set_ce(inner_iph);
-}
-
static int xfrm4_parse_spi(struct sk_buff *skb, u8 nexthdr, u32 *spi, u32 *seq)
{
switch (nexthdr) {
@@ -113,24 +103,10 @@
xfrm_vec[xfrm_nr++] = x;
- iph = skb->nh.iph;
+ if (x->mode->input(x, skb))
+ goto drop;
if (x->props.mode) {
- if (iph->protocol != IPPROTO_IPIP)
- goto drop;
- if (!pskb_may_pull(skb, sizeof(struct iphdr)))
- goto drop;
- if (skb_cloned(skb) &&
- pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
- goto drop;
- if (x->props.flags & XFRM_STATE_DECAP_DSCP)
- ipv4_copy_dscp(iph, skb->h.ipiph);
- if (!(x->props.flags & XFRM_STATE_NOECN))
- ipip_ecn_decapsulate(skb);
- skb->mac.raw = memmove(skb->data - skb->mac_len,
- skb->mac.raw, skb->mac_len);
- skb->nh.raw = skb->data;
- memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
decaps = 1;
break;
}
diff --git a/net/ipv4/xfrm4_mode_transport.c b/net/ipv4/xfrm4_mode_transport.c
new file mode 100644
index 0000000..e46d9a4
--- /dev/null
+++ b/net/ipv4/xfrm4_mode_transport.c
@@ -0,0 +1,69 @@
+/*
+ * xfrm4_mode_transport.c - Transport mode encapsulation for IPv4.
+ *
+ * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/stringify.h>
+#include <net/dst.h>
+#include <net/ip.h>
+#include <net/xfrm.h>
+
+/* Add encapsulation header.
+ *
+ * The IP header will be moved forward to make space for the encapsulation
+ * header.
+ *
+ * On exit, skb->h will be set to the start of the payload to be processed
+ * by x->type->output and skb->nh will be set to the top IP header.
+ */
+static int xfrm4_transport_output(struct sk_buff *skb)
+{
+ struct xfrm_state *x;
+ struct iphdr *iph;
+ int ihl;
+
+ iph = skb->nh.iph;
+ skb->h.ipiph = iph;
+
+ ihl = iph->ihl * 4;
+ skb->h.raw += ihl;
+
+ x = skb->dst->xfrm;
+ skb->nh.raw = memmove(skb_push(skb, x->props.header_len), iph, ihl);
+ return 0;
+}
+
+static int xfrm4_transport_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+ return 0;
+}
+
+static struct xfrm_mode xfrm4_transport_mode = {
+ .input = xfrm4_transport_input,
+ .output = xfrm4_transport_output,
+ .owner = THIS_MODULE,
+ .encap = XFRM_MODE_TRANSPORT,
+};
+
+static int __init xfrm4_transport_init(void)
+{
+ return xfrm_register_mode(&xfrm4_transport_mode, AF_INET);
+}
+
+static void __exit xfrm4_transport_exit(void)
+{
+ int err;
+
+ err = xfrm_unregister_mode(&xfrm4_transport_mode, AF_INET);
+ BUG_ON(err);
+}
+
+module_init(xfrm4_transport_init);
+module_exit(xfrm4_transport_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_MODE(AF_INET, XFRM_MODE_TRANSPORT);
diff --git a/net/ipv4/xfrm4_mode_tunnel.c b/net/ipv4/xfrm4_mode_tunnel.c
new file mode 100644
index 0000000..f8d880b
--- /dev/null
+++ b/net/ipv4/xfrm4_mode_tunnel.c
@@ -0,0 +1,125 @@
+/*
+ * xfrm4_mode_tunnel.c - Tunnel mode encapsulation for IPv4.
+ *
+ * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/stringify.h>
+#include <net/dst.h>
+#include <net/inet_ecn.h>
+#include <net/ip.h>
+#include <net/xfrm.h>
+
+static inline void ipip_ecn_decapsulate(struct sk_buff *skb)
+{
+ struct iphdr *outer_iph = skb->nh.iph;
+ struct iphdr *inner_iph = skb->h.ipiph;
+
+ if (INET_ECN_is_ce(outer_iph->tos))
+ IP_ECN_set_ce(inner_iph);
+}
+
+/* Add encapsulation header.
+ *
+ * The top IP header will be constructed per RFC 2401. The following fields
+ * in it shall be filled in by x->type->output:
+ * tot_len
+ * check
+ *
+ * On exit, skb->h will be set to the start of the payload to be processed
+ * by x->type->output and skb->nh will be set to the top IP header.
+ */
+static int xfrm4_tunnel_output(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb->dst;
+ struct xfrm_state *x = dst->xfrm;
+ struct iphdr *iph, *top_iph;
+ int flags;
+
+ iph = skb->nh.iph;
+ skb->h.ipiph = iph;
+
+ skb->nh.raw = skb_push(skb, x->props.header_len);
+ top_iph = skb->nh.iph;
+
+ top_iph->ihl = 5;
+ top_iph->version = 4;
+
+ /* DS disclosed */
+ top_iph->tos = INET_ECN_encapsulate(iph->tos, iph->tos);
+
+ flags = x->props.flags;
+ if (flags & XFRM_STATE_NOECN)
+ IP_ECN_clear(top_iph);
+
+ top_iph->frag_off = (flags & XFRM_STATE_NOPMTUDISC) ?
+ 0 : (iph->frag_off & htons(IP_DF));
+ if (!top_iph->frag_off)
+ __ip_select_ident(top_iph, dst->child, 0);
+
+ top_iph->ttl = dst_metric(dst->child, RTAX_HOPLIMIT);
+
+ top_iph->saddr = x->props.saddr.a4;
+ top_iph->daddr = x->id.daddr.a4;
+ top_iph->protocol = IPPROTO_IPIP;
+
+ memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+ return 0;
+}
+
+static int xfrm4_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+ struct iphdr *iph = skb->nh.iph;
+ int err = -EINVAL;
+
+ if (iph->protocol != IPPROTO_IPIP)
+ goto out;
+ if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+ goto out;
+
+ if (skb_cloned(skb) &&
+ (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
+ goto out;
+
+ if (x->props.flags & XFRM_STATE_DECAP_DSCP)
+ ipv4_copy_dscp(iph, skb->h.ipiph);
+ if (!(x->props.flags & XFRM_STATE_NOECN))
+ ipip_ecn_decapsulate(skb);
+ skb->mac.raw = memmove(skb->data - skb->mac_len,
+ skb->mac.raw, skb->mac_len);
+ skb->nh.raw = skb->data;
+ memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+ err = 0;
+
+out:
+ return err;
+}
+
+static struct xfrm_mode xfrm4_tunnel_mode = {
+ .input = xfrm4_tunnel_input,
+ .output = xfrm4_tunnel_output,
+ .owner = THIS_MODULE,
+ .encap = XFRM_MODE_TUNNEL,
+};
+
+static int __init xfrm4_tunnel_init(void)
+{
+ return xfrm_register_mode(&xfrm4_tunnel_mode, AF_INET);
+}
+
+static void __exit xfrm4_tunnel_exit(void)
+{
+ int err;
+
+ err = xfrm_unregister_mode(&xfrm4_tunnel_mode, AF_INET);
+ BUG_ON(err);
+}
+
+module_init(xfrm4_tunnel_init);
+module_exit(xfrm4_tunnel_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_MODE(AF_INET, XFRM_MODE_TUNNEL);
diff --git a/net/ipv4/xfrm4_output.c b/net/ipv4/xfrm4_output.c
index 4ef8efa..ac9d91d 100644
--- a/net/ipv4/xfrm4_output.c
+++ b/net/ipv4/xfrm4_output.c
@@ -12,67 +12,10 @@
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/netfilter_ipv4.h>
-#include <net/inet_ecn.h>
#include <net/ip.h>
#include <net/xfrm.h>
#include <net/icmp.h>
-/* Add encapsulation header.
- *
- * In transport mode, the IP header will be moved forward to make space
- * for the encapsulation header.
- *
- * In tunnel mode, the top IP header will be constructed per RFC 2401.
- * The following fields in it shall be filled in by x->type->output:
- * tot_len
- * check
- *
- * On exit, skb->h will be set to the start of the payload to be processed
- * by x->type->output and skb->nh will be set to the top IP header.
- */
-static void xfrm4_encap(struct sk_buff *skb)
-{
- struct dst_entry *dst = skb->dst;
- struct xfrm_state *x = dst->xfrm;
- struct iphdr *iph, *top_iph;
- int flags;
-
- iph = skb->nh.iph;
- skb->h.ipiph = iph;
-
- skb->nh.raw = skb_push(skb, x->props.header_len);
- top_iph = skb->nh.iph;
-
- if (!x->props.mode) {
- skb->h.raw += iph->ihl*4;
- memmove(top_iph, iph, iph->ihl*4);
- return;
- }
-
- top_iph->ihl = 5;
- top_iph->version = 4;
-
- /* DS disclosed */
- top_iph->tos = INET_ECN_encapsulate(iph->tos, iph->tos);
-
- flags = x->props.flags;
- if (flags & XFRM_STATE_NOECN)
- IP_ECN_clear(top_iph);
-
- top_iph->frag_off = (flags & XFRM_STATE_NOPMTUDISC) ?
- 0 : (iph->frag_off & htons(IP_DF));
- if (!top_iph->frag_off)
- __ip_select_ident(top_iph, dst->child, 0);
-
- top_iph->ttl = dst_metric(dst->child, RTAX_HOPLIMIT);
-
- top_iph->saddr = x->props.saddr.a4;
- top_iph->daddr = x->id.daddr.a4;
- top_iph->protocol = IPPROTO_IPIP;
-
- memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
-}
-
static int xfrm4_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
@@ -121,7 +64,9 @@
if (err)
goto error;
- xfrm4_encap(skb);
+ err = x->mode->output(skb);
+ if (err)
+ goto error;
err = x->type->output(x, skb);
if (err)
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index f8a107a..e923d4d 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -106,6 +106,26 @@
tristate
default n
+config INET6_XFRM_MODE_TRANSPORT
+ tristate "IPv6: IPsec transport mode"
+ depends on IPV6
+ default IPV6
+ select XFRM
+ ---help---
+ Support for IPsec transport mode.
+
+ If unsure, say Y.
+
+config INET6_XFRM_MODE_TUNNEL
+ tristate "IPv6: IPsec tunnel mode"
+ depends on IPV6
+ default IPV6
+ select XFRM
+ ---help---
+ Support for IPsec tunnel mode.
+
+ If unsure, say Y.
+
config IPV6_TUNNEL
tristate "IPv6: IPv6-in-IPv6 tunnel"
select INET6_TUNNEL
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index a760b09..386e0a6 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -20,6 +20,8 @@
obj-$(CONFIG_INET6_IPCOMP) += ipcomp6.o
obj-$(CONFIG_INET6_XFRM_TUNNEL) += xfrm6_tunnel.o
obj-$(CONFIG_INET6_TUNNEL) += tunnel6.o
+obj-$(CONFIG_INET6_XFRM_MODE_TRANSPORT) += xfrm6_mode_transport.o
+obj-$(CONFIG_INET6_XFRM_MODE_TUNNEL) += xfrm6_mode_tunnel.o
obj-$(CONFIG_NETFILTER) += netfilter/
obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index e460489..416f6e4 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -39,6 +39,7 @@
#include <linux/in6.h>
#include <linux/tcp.h>
#include <linux/route.h>
+#include <linux/module.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.h>
@@ -488,6 +489,7 @@
return offset;
}
+EXPORT_SYMBOL_GPL(ip6_find_1stfragopt);
static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
{
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 00cfdee..0405d74 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -13,21 +13,9 @@
#include <linux/string.h>
#include <linux/netfilter.h>
#include <linux/netfilter_ipv6.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 *skb, u32 spi)
{
int err;
@@ -81,21 +69,10 @@
xfrm_vec[xfrm_nr++] = x;
+ if (x->mode->input(x, skb))
+ goto drop;
+
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;
}
diff --git a/net/ipv6/xfrm6_mode_transport.c b/net/ipv6/xfrm6_mode_transport.c
new file mode 100644
index 0000000..5efbbae
--- /dev/null
+++ b/net/ipv6/xfrm6_mode_transport.c
@@ -0,0 +1,73 @@
+/*
+ * xfrm6_mode_transport.c - Transport mode encapsulation for IPv6.
+ *
+ * Copyright (C) 2002 USAGI/WIDE Project
+ * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/stringify.h>
+#include <net/dst.h>
+#include <net/ipv6.h>
+#include <net/xfrm.h>
+
+/* Add encapsulation header.
+ *
+ * The IP header and mutable extension headers will be moved forward to make
+ * space for the encapsulation header.
+ *
+ * On exit, skb->h will be set to the start of the encapsulation header to be
+ * filled in by x->type->output and skb->nh will be set to the nextheader field
+ * of the extension header directly preceding the encapsulation header, or in
+ * its absence, that of the top IP header. The value of skb->data will always
+ * point to the top IP header.
+ */
+static int xfrm6_transport_output(struct sk_buff *skb)
+{
+ struct xfrm_state *x = skb->dst->xfrm;
+ struct ipv6hdr *iph;
+ u8 *prevhdr;
+ int hdr_len;
+
+ skb_push(skb, x->props.header_len);
+ iph = skb->nh.ipv6h;
+
+ hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
+ skb->nh.raw = prevhdr - x->props.header_len;
+ skb->h.raw = skb->data + hdr_len;
+ memmove(skb->data, iph, hdr_len);
+ return 0;
+}
+
+static int xfrm6_transport_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+ return 0;
+}
+
+static struct xfrm_mode xfrm6_transport_mode = {
+ .input = xfrm6_transport_input,
+ .output = xfrm6_transport_output,
+ .owner = THIS_MODULE,
+ .encap = XFRM_MODE_TRANSPORT,
+};
+
+static int __init xfrm6_transport_init(void)
+{
+ return xfrm_register_mode(&xfrm6_transport_mode, AF_INET6);
+}
+
+static void __exit xfrm6_transport_exit(void)
+{
+ int err;
+
+ err = xfrm_unregister_mode(&xfrm6_transport_mode, AF_INET6);
+ BUG_ON(err);
+}
+
+module_init(xfrm6_transport_init);
+module_exit(xfrm6_transport_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TRANSPORT);
diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c
new file mode 100644
index 0000000..8af79be2
--- /dev/null
+++ b/net/ipv6/xfrm6_mode_tunnel.c
@@ -0,0 +1,121 @@
+/*
+ * xfrm6_mode_tunnel.c - Tunnel mode encapsulation for IPv6.
+ *
+ * Copyright (C) 2002 USAGI/WIDE Project
+ * Copyright (c) 2004-2006 Herbert Xu <herbert@gondor.apana.org.au>
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/skbuff.h>
+#include <linux/stringify.h>
+#include <net/dsfield.h>
+#include <net/dst.h>
+#include <net/inet_ecn.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);
+}
+
+/* Add encapsulation header.
+ *
+ * The top IP header will be constructed per RFC 2401. The following fields
+ * in it shall be filled in by x->type->output:
+ * payload_len
+ *
+ * On exit, skb->h will be set to the start of the encapsulation header to be
+ * filled in by x->type->output and skb->nh will be set to the nextheader field
+ * of the extension header directly preceding the encapsulation header, or in
+ * its absence, that of the top IP header. The value of skb->data will always
+ * point to the top IP header.
+ */
+static int xfrm6_tunnel_output(struct sk_buff *skb)
+{
+ struct dst_entry *dst = skb->dst;
+ struct xfrm_state *x = dst->xfrm;
+ struct ipv6hdr *iph, *top_iph;
+ int dsfield;
+
+ skb_push(skb, x->props.header_len);
+ iph = skb->nh.ipv6h;
+
+ skb->nh.raw = skb->data;
+ top_iph = skb->nh.ipv6h;
+ skb->nh.raw = &top_iph->nexthdr;
+ skb->h.ipv6h = top_iph + 1;
+
+ top_iph->version = 6;
+ top_iph->priority = iph->priority;
+ top_iph->flow_lbl[0] = iph->flow_lbl[0];
+ top_iph->flow_lbl[1] = iph->flow_lbl[1];
+ top_iph->flow_lbl[2] = iph->flow_lbl[2];
+ dsfield = ipv6_get_dsfield(top_iph);
+ dsfield = INET_ECN_encapsulate(dsfield, dsfield);
+ if (x->props.flags & XFRM_STATE_NOECN)
+ dsfield &= ~INET_ECN_MASK;
+ ipv6_change_dsfield(top_iph, 0, dsfield);
+ top_iph->nexthdr = IPPROTO_IPV6;
+ top_iph->hop_limit = dst_metric(dst->child, RTAX_HOPLIMIT);
+ ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr);
+ ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr);
+ return 0;
+}
+
+static int xfrm6_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
+{
+ int err = -EINVAL;
+
+ if (skb->nh.raw[IP6CB(skb)->nhoff] != IPPROTO_IPV6)
+ goto out;
+ if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+ goto out;
+
+ if (skb_cloned(skb) &&
+ (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
+ goto out;
+
+ 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;
+ err = 0;
+
+out:
+ return err;
+}
+
+static struct xfrm_mode xfrm6_tunnel_mode = {
+ .input = xfrm6_tunnel_input,
+ .output = xfrm6_tunnel_output,
+ .owner = THIS_MODULE,
+ .encap = XFRM_MODE_TUNNEL,
+};
+
+static int __init xfrm6_tunnel_init(void)
+{
+ return xfrm_register_mode(&xfrm6_tunnel_mode, AF_INET6);
+}
+
+static void __exit xfrm6_tunnel_exit(void)
+{
+ int err;
+
+ err = xfrm_unregister_mode(&xfrm6_tunnel_mode, AF_INET6);
+ BUG_ON(err);
+}
+
+module_init(xfrm6_tunnel_init);
+module_exit(xfrm6_tunnel_exit);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_XFRM_MODE(AF_INET6, XFRM_MODE_TUNNEL);
diff --git a/net/ipv6/xfrm6_output.c b/net/ipv6/xfrm6_output.c
index 8024217..16e8425 100644
--- a/net/ipv6/xfrm6_output.c
+++ b/net/ipv6/xfrm6_output.c
@@ -14,68 +14,9 @@
#include <linux/spinlock.h>
#include <linux/icmpv6.h>
#include <linux/netfilter_ipv6.h>
-#include <net/dsfield.h>
-#include <net/inet_ecn.h>
#include <net/ipv6.h>
#include <net/xfrm.h>
-/* Add encapsulation header.
- *
- * In transport mode, the IP header and mutable extension headers will be moved
- * forward to make space for the encapsulation header.
- *
- * In tunnel mode, the top IP header will be constructed per RFC 2401.
- * The following fields in it shall be filled in by x->type->output:
- * payload_len
- *
- * On exit, skb->h will be set to the start of the encapsulation header to be
- * filled in by x->type->output and skb->nh will be set to the nextheader field
- * of the extension header directly preceding the encapsulation header, or in
- * its absence, that of the top IP header. The value of skb->data will always
- * point to the top IP header.
- */
-static void xfrm6_encap(struct sk_buff *skb)
-{
- struct dst_entry *dst = skb->dst;
- struct xfrm_state *x = dst->xfrm;
- struct ipv6hdr *iph, *top_iph;
- int dsfield;
-
- skb_push(skb, x->props.header_len);
- iph = skb->nh.ipv6h;
-
- if (!x->props.mode) {
- u8 *prevhdr;
- int hdr_len;
-
- hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
- skb->nh.raw = prevhdr - x->props.header_len;
- skb->h.raw = skb->data + hdr_len;
- memmove(skb->data, iph, hdr_len);
- return;
- }
-
- skb->nh.raw = skb->data;
- top_iph = skb->nh.ipv6h;
- skb->nh.raw = &top_iph->nexthdr;
- skb->h.ipv6h = top_iph + 1;
-
- top_iph->version = 6;
- top_iph->priority = iph->priority;
- top_iph->flow_lbl[0] = iph->flow_lbl[0];
- top_iph->flow_lbl[1] = iph->flow_lbl[1];
- top_iph->flow_lbl[2] = iph->flow_lbl[2];
- dsfield = ipv6_get_dsfield(top_iph);
- dsfield = INET_ECN_encapsulate(dsfield, dsfield);
- if (x->props.flags & XFRM_STATE_NOECN)
- dsfield &= ~INET_ECN_MASK;
- ipv6_change_dsfield(top_iph, 0, dsfield);
- top_iph->nexthdr = IPPROTO_IPV6;
- top_iph->hop_limit = dst_metric(dst->child, RTAX_HOPLIMIT);
- ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr);
- ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr);
-}
-
static int xfrm6_tunnel_check_size(struct sk_buff *skb)
{
int mtu, ret = 0;
@@ -118,7 +59,9 @@
if (err)
goto error;
- xfrm6_encap(skb);
+ err = x->mode->output(skb);
+ if (err)
+ goto error;
err = x->type->output(x, skb);
if (err)
diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c
index 44b64a5..b893692 100644
--- a/net/xfrm/xfrm_policy.c
+++ b/net/xfrm/xfrm_policy.c
@@ -138,6 +138,89 @@
module_put(type->owner);
}
+int xfrm_register_mode(struct xfrm_mode *mode, int family)
+{
+ struct xfrm_policy_afinfo *afinfo;
+ struct xfrm_mode **modemap;
+ int err;
+
+ if (unlikely(mode->encap >= XFRM_MODE_MAX))
+ return -EINVAL;
+
+ afinfo = xfrm_policy_lock_afinfo(family);
+ if (unlikely(afinfo == NULL))
+ return -EAFNOSUPPORT;
+
+ err = -EEXIST;
+ modemap = afinfo->mode_map;
+ if (likely(modemap[mode->encap] == NULL)) {
+ modemap[mode->encap] = mode;
+ err = 0;
+ }
+
+ xfrm_policy_unlock_afinfo(afinfo);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_register_mode);
+
+int xfrm_unregister_mode(struct xfrm_mode *mode, int family)
+{
+ struct xfrm_policy_afinfo *afinfo;
+ struct xfrm_mode **modemap;
+ int err;
+
+ if (unlikely(mode->encap >= XFRM_MODE_MAX))
+ return -EINVAL;
+
+ afinfo = xfrm_policy_lock_afinfo(family);
+ if (unlikely(afinfo == NULL))
+ return -EAFNOSUPPORT;
+
+ err = -ENOENT;
+ modemap = afinfo->mode_map;
+ if (likely(modemap[mode->encap] == mode)) {
+ modemap[mode->encap] = NULL;
+ err = 0;
+ }
+
+ xfrm_policy_unlock_afinfo(afinfo);
+ return err;
+}
+EXPORT_SYMBOL(xfrm_unregister_mode);
+
+struct xfrm_mode *xfrm_get_mode(unsigned int encap, int family)
+{
+ struct xfrm_policy_afinfo *afinfo;
+ struct xfrm_mode *mode;
+ int modload_attempted = 0;
+
+ if (unlikely(encap >= XFRM_MODE_MAX))
+ return NULL;
+
+retry:
+ afinfo = xfrm_policy_get_afinfo(family);
+ if (unlikely(afinfo == NULL))
+ return NULL;
+
+ mode = afinfo->mode_map[encap];
+ if (unlikely(mode && !try_module_get(mode->owner)))
+ mode = NULL;
+ if (!mode && !modload_attempted) {
+ xfrm_policy_put_afinfo(afinfo);
+ request_module("xfrm-mode-%d-%d", family, encap);
+ modload_attempted = 1;
+ goto retry;
+ }
+
+ xfrm_policy_put_afinfo(afinfo);
+ return mode;
+}
+
+void xfrm_put_mode(struct xfrm_mode *mode)
+{
+ module_put(mode->owner);
+}
+
static inline unsigned long make_jiffies(long secs)
{
if (secs >= (MAX_SCHEDULE_TIMEOUT-1)/HZ)
diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c
index ee62c23..17b29ec 100644
--- a/net/xfrm/xfrm_state.c
+++ b/net/xfrm/xfrm_state.c
@@ -77,6 +77,8 @@
kfree(x->ealg);
kfree(x->calg);
kfree(x->encap);
+ if (x->mode)
+ xfrm_put_mode(x->mode);
if (x->type) {
x->type->destructor(x);
xfrm_put_type(x->type);
@@ -1193,6 +1195,10 @@
if (err)
goto error;
+ x->mode = xfrm_get_mode(x->props.mode, family);
+ if (x->mode == NULL)
+ goto error;
+
x->km.state = XFRM_STATE_VALID;
error: