[PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[Martin Willi]

Add new_mapping() implementation to the netlink xfrm_mgr to notify
address/port changes detected in UDP encapsulated ESP packets.

Signed-off-by: Martin Willi <martin@strongswan.org>

diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index 4bc1e6b..52f3abd 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -199,6 +199,9 @@ enum {
 #define XFRM_MSG_NEWSPDINFO XFRM_MSG_NEWSPDINFO
 	XFRM_MSG_GETSPDINFO,
 #define XFRM_MSG_GETSPDINFO XFRM_MSG_GETSPDINFO
+
+	XFRM_MSG_MAPPING,
+#define XFRM_MSG_MAPPING XFRM_MSG_MAPPING
 	__XFRM_MSG_MAX
 };
 #define XFRM_MSG_MAX (__XFRM_MSG_MAX - 1)
@@ -438,6 +441,15 @@ struct xfrm_user_migrate {
 	__u16				new_family;
 };
 
+struct xfrm_user_mapping {
+	struct xfrm_usersa_id		id;
+	__u32				reqid;
+	xfrm_address_t			old_saddr;
+	xfrm_address_t			new_saddr;
+	__be16				old_sport;
+	__be16				new_sport;
+};
+
 #ifndef __KERNEL__
 /* backwards compatibility for userspace */
 #define XFRMGRP_ACQUIRE		1
@@ -464,6 +476,8 @@ enum xfrm_nlgroups {
 #define XFRMNLGRP_REPORT	XFRMNLGRP_REPORT
 	XFRMNLGRP_MIGRATE,
 #define XFRMNLGRP_MIGRATE	XFRMNLGRP_MIGRATE
+	XFRMNLGRP_MAPPING,
+#define XFRMNLGRP_MAPPING	XFRMNLGRP_MAPPING
 	__XFRMNLGRP_MAX
 };
 #define XFRMNLGRP_MAX	(__XFRMNLGRP_MAX - 1)
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 4a8a1ab..499a516 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2503,6 +2503,57 @@ static int xfrm_send_report(u8 proto, struct xfrm_selector *sel,
 	return nlmsg_multicast(xfrm_nl, skb, 0, XFRMNLGRP_REPORT, GFP_ATOMIC);
 }
 
+static inline size_t xfrm_mapping_msgsize(void)
+{
+	return NLMSG_ALIGN(sizeof(struct xfrm_user_mapping));
+}
+
+static int build_mapping(struct sk_buff *skb, struct xfrm_state *x,
+			 xfrm_address_t *new_saddr, __be16 new_sport)
+{
+	struct xfrm_user_mapping *um;
+	struct nlmsghdr *nlh;
+
+	nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_MAPPING, sizeof(*um), 0);
+	if (nlh == NULL)
+		return -EMSGSIZE;
+
+	um = nlmsg_data(nlh);
+	
+	memcpy(&um->id.daddr, &x->id.daddr, sizeof(um->id.daddr));
+	um->id.spi = x->id.spi;
+	um->id.family = x->props.family;
+	um->id.proto = x->id.proto;
+	memcpy(&um->new_saddr, new_saddr, sizeof(um->new_saddr));
+	memcpy(&um->old_saddr, &x->props.saddr, sizeof(um->old_saddr));
+	um->new_sport = new_sport;
+	um->old_sport = x->encap->encap_sport;
+	um->reqid = x->props.reqid;
+
+	return nlmsg_end(skb, nlh);
+}
+
+static int xfrm_send_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr,
+			     __be16 sport)
+{
+	struct sk_buff *skb;
+
+	if (x->id.proto != IPPROTO_ESP)
+		return -EINVAL;
+
+	if (!x->encap)
+		return -EINVAL;
+
+	skb = nlmsg_new(xfrm_mapping_msgsize(), GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+
+	if (build_mapping(skb, x, ipaddr, sport) < 0)
+		BUG();
+
+	return nlmsg_multicast(xfrm_nl, skb, 0, XFRMNLGRP_MAPPING, GFP_ATOMIC);
+}
+
 static struct xfrm_mgr netlink_mgr = {
 	.id		= "netlink",
 	.notify		= xfrm_send_state_notify,
@@ -2511,6 +2562,7 @@ static struct xfrm_mgr netlink_mgr = {
 	.notify_policy	= xfrm_send_policy_notify,
 	.report		= xfrm_send_report,
 	.migrate	= xfrm_send_migrate,
+	.new_mapping	= xfrm_send_mapping,
 };
 
 static int __init xfrm_user_init(void)

Re: [PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[David Miller]

From: martin@strongswan.org (Martin Willi)
Date: Mon, 13 Oct 2008 11:27:26 +0200 (CEST)

> Add new_mapping() implementation to the netlink xfrm_mgr to notify
> address/port changes detected in UDP encapsulated ESP packets.
> 
> Signed-off-by: Martin Willi <martin@strongswan.org>

This has to wait until the next merge window.

Please resubmit this 2 or so weeks from now, which is when I'll
likely start taking 2.6.29 bound networking stuff.

[PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[Martin Willi]

Add new_mapping() implementation to the netlink xfrm_mgr to notify
address/port changes detected in UDP encapsulated ESP packets.

Signed-off-by: Martin Willi <martin@strongswan.org>

diff --git a/include/linux/xfrm.h b/include/linux/xfrm.h
index 4bc1e6b..52f3abd 100644
--- a/include/linux/xfrm.h
+++ b/include/linux/xfrm.h
@@ -199,6 +199,9 @@ enum {
 #define XFRM_MSG_NEWSPDINFO XFRM_MSG_NEWSPDINFO
 	XFRM_MSG_GETSPDINFO,
 #define XFRM_MSG_GETSPDINFO XFRM_MSG_GETSPDINFO
+
+	XFRM_MSG_MAPPING,
+#define XFRM_MSG_MAPPING XFRM_MSG_MAPPING
 	__XFRM_MSG_MAX
 };
 #define XFRM_MSG_MAX (__XFRM_MSG_MAX - 1)
@@ -438,6 +441,15 @@ struct xfrm_user_migrate {
 	__u16				new_family;
 };
 
+struct xfrm_user_mapping {
+	struct xfrm_usersa_id		id;
+	__u32				reqid;
+	xfrm_address_t			old_saddr;
+	xfrm_address_t			new_saddr;
+	__be16				old_sport;
+	__be16				new_sport;
+};
+
 #ifndef __KERNEL__
 /* backwards compatibility for userspace */
 #define XFRMGRP_ACQUIRE		1
@@ -464,6 +476,8 @@ enum xfrm_nlgroups {
 #define XFRMNLGRP_REPORT	XFRMNLGRP_REPORT
 	XFRMNLGRP_MIGRATE,
 #define XFRMNLGRP_MIGRATE	XFRMNLGRP_MIGRATE
+	XFRMNLGRP_MAPPING,
+#define XFRMNLGRP_MAPPING	XFRMNLGRP_MAPPING
 	__XFRMNLGRP_MAX
 };
 #define XFRMNLGRP_MAX	(__XFRMNLGRP_MAX - 1)
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 4a8a1ab..499a516 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -2503,6 +2503,57 @@ static int xfrm_send_report(u8 proto, struct xfrm_selector *sel,
 	return nlmsg_multicast(xfrm_nl, skb, 0, XFRMNLGRP_REPORT, GFP_ATOMIC);
 }
 
+static inline size_t xfrm_mapping_msgsize(void)
+{
+	return NLMSG_ALIGN(sizeof(struct xfrm_user_mapping));
+}
+
+static int build_mapping(struct sk_buff *skb, struct xfrm_state *x,
+			 xfrm_address_t *new_saddr, __be16 new_sport)
+{
+	struct xfrm_user_mapping *um;
+	struct nlmsghdr *nlh;
+
+	nlh = nlmsg_put(skb, 0, 0, XFRM_MSG_MAPPING, sizeof(*um), 0);
+	if (nlh == NULL)
+		return -EMSGSIZE;
+
+	um = nlmsg_data(nlh);
+	
+	memcpy(&um->id.daddr, &x->id.daddr, sizeof(um->id.daddr));
+	um->id.spi = x->id.spi;
+	um->id.family = x->props.family;
+	um->id.proto = x->id.proto;
+	memcpy(&um->new_saddr, new_saddr, sizeof(um->new_saddr));
+	memcpy(&um->old_saddr, &x->props.saddr, sizeof(um->old_saddr));
+	um->new_sport = new_sport;
+	um->old_sport = x->encap->encap_sport;
+	um->reqid = x->props.reqid;
+
+	return nlmsg_end(skb, nlh);
+}
+
+static int xfrm_send_mapping(struct xfrm_state *x, xfrm_address_t *ipaddr,
+			     __be16 sport)
+{
+	struct sk_buff *skb;
+
+	if (x->id.proto != IPPROTO_ESP)
+		return -EINVAL;
+
+	if (!x->encap)
+		return -EINVAL;
+
+	skb = nlmsg_new(xfrm_mapping_msgsize(), GFP_ATOMIC);
+	if (skb == NULL)
+		return -ENOMEM;
+
+	if (build_mapping(skb, x, ipaddr, sport) < 0)
+		BUG();
+
+	return nlmsg_multicast(xfrm_nl, skb, 0, XFRMNLGRP_MAPPING, GFP_ATOMIC);
+}
+
 static struct xfrm_mgr netlink_mgr = {
 	.id		= "netlink",
 	.notify		= xfrm_send_state_notify,
@@ -2511,6 +2562,7 @@ static struct xfrm_mgr netlink_mgr = {
 	.notify_policy	= xfrm_send_policy_notify,
 	.report		= xfrm_send_report,
 	.migrate	= xfrm_send_migrate,
+	.new_mapping	= xfrm_send_mapping,
 };
 
 static int __init xfrm_user_init(void)

Re: [PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[David Miller]

From: martin@strongswan.org (Martin Willi)
Date: Tue, 28 Oct 2008 09:51:19 +0100 (CET)

> Add new_mapping() implementation to the netlink xfrm_mgr to notify
> address/port changes detected in UDP encapsulated ESP packets.
> 
> Signed-off-by: Martin Willi <martin@strongswan.org>

I don't see the code which will actually invoke the new
->new_mapping() method (either here or in a follow-on patch), so it's
impossible to review these changes.

Re: [PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[Martin Willi]

> I don't see the code which will actually invoke the new
> ->new_mapping() method (either here or in a follow-on patch), so it's
> impossible to review these changes.

The patch is complete, sorry for being unclear.

xfrm_send_mapping is an implementation of a xfrm_mgr operation. 

>  static struct xfrm_mgr netlink_mgr = {
>         .id             = "netlink",
>         .notify         = xfrm_send_state_notify,
>         .notify_policy  = xfrm_send_policy_notify,
>         .report         = xfrm_send_report,
>         .migrate        = xfrm_send_migrate,
> +       .new_mapping    = xfrm_send_mapping,
> };

This operation is invoked from net/ipv4/esp4.c through the
km_new_mapping() function, km_new_mapping() invokes all registered key
managers. It is already implemented in the PF_KEY interface (pfkeyv2_mgr
in af_key.c), but is missing in the netlink xfrm interface. The patch
adds this functionality to the netlink interface.

Re: [PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[David Miller]

From: Martin Willi <martin@strongswan.org>
Date: Tue, 28 Oct 2008 21:44:20 +0100

> >  static struct xfrm_mgr netlink_mgr = {
> >         .id             = "netlink",
> >         .notify         = xfrm_send_state_notify,
> >         .notify_policy  = xfrm_send_policy_notify,
> >         .report         = xfrm_send_report,
> >         .migrate        = xfrm_send_migrate,
> > +       .new_mapping    = xfrm_send_mapping,
> > };
> 
> This operation is invoked from net/ipv4/esp4.c through the
> km_new_mapping() function, km_new_mapping() invokes all registered key
> managers. It is already implemented in the PF_KEY interface (pfkeyv2_mgr
> in af_key.c), but is missing in the netlink xfrm interface. The patch
> adds this functionality to the netlink interface.

Sorry, I didn't pick up on that.  Thanks for the explanation.

Re: [PATCH] xfrm: Notify changes in UDP encapsulation via netlink

[David Miller]

From: martin@strongswan.org (Martin Willi)
Date: Tue, 28 Oct 2008 09:51:19 +0100 (CET)

> Add new_mapping() implementation to the netlink xfrm_mgr to notify
> address/port changes detected in UDP encapsulated ESP packets.
> 
> Signed-off-by: Martin Willi <martin@strongswan.org>

Applied, thanks a lot.

> +	um = nlmsg_data(nlh);
> +	
> +	memcpy(&um->id.daddr, &x->id.daddr, sizeof(um->id.daddr));

That second line has trailing whitespace which I fixed up by hand
when applying this patch.

Please avoid this in the future.