[net-next] ipv6: sr: export some functions of seg6local

[net-next] ipv6: sr: export some functions of seg6local

[Ahmed Abdelsalam]

Some functions of seg6local are very useful to process SRv6
encapsulated packets.

This patch exports some functions of seg6local that are useful and
can be re-used at different parts of the kernel.

The set of exported functions are:
(1) get_srh()
(2) advance_nextseg()
(3) lookup_nexthop

Signed-off-by: Ahmed Abdelsalam <amsalam20@gmail.com>
---
I'm writing some extensions to netfilter framework to support
Segment Routing. These function are useful to process
SR-encapsulated packets

 include/net/seg6.h    |  4 ++++
 net/ipv6/seg6_local.c | 11 +++++++----
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/include/net/seg6.h b/include/net/seg6.h
index 099bad5..4058f23 100644
--- a/include/net/seg6.h
+++ b/include/net/seg6.h
@@ -60,6 +60,10 @@ extern int seg6_local_init(void);
 extern void seg6_local_exit(void);
 
 extern bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len);
+extern struct ipv6_sr_hdr *get_srh(struct sk_buff *skb);
+extern void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr);
+extern void lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
+			u32 tbl_id);
 extern int seg6_do_srh_encap(struct sk_buff *skb, struct ipv6_sr_hdr *osrh,
 			     int proto);
 extern int seg6_do_srh_inline(struct sk_buff *skb, struct ipv6_sr_hdr *osrh);
diff --git a/net/ipv6/seg6_local.c b/net/ipv6/seg6_local.c
index 825b8e0..5661d6c 100644
--- a/net/ipv6/seg6_local.c
+++ b/net/ipv6/seg6_local.c
@@ -59,7 +59,7 @@ static struct seg6_local_lwt *seg6_local_lwtunnel(struct lwtunnel_state *lwt)
 	return (struct seg6_local_lwt *)lwt->data;
 }
 
-static struct ipv6_sr_hdr *get_srh(struct sk_buff *skb)
+struct ipv6_sr_hdr *get_srh(struct sk_buff *skb)
 {
 	struct ipv6_sr_hdr *srh;
 	int len, srhoff = 0;
@@ -82,6 +82,7 @@ static struct ipv6_sr_hdr *get_srh(struct sk_buff *skb)
 
 	return srh;
 }
+EXPORT_SYMBOL_GPL(get_srh);
 
 static struct ipv6_sr_hdr *get_and_validate_srh(struct sk_buff *skb)
 {
@@ -131,7 +132,7 @@ static bool decap_and_validate(struct sk_buff *skb, int proto)
 	return true;
 }
 
-static void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr)
+void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr)
 {
 	struct in6_addr *addr;
 
@@ -139,9 +140,10 @@ static void advance_nextseg(struct ipv6_sr_hdr *srh, struct in6_addr *daddr)
 	addr = srh->segments + srh->segments_left;
 	*daddr = *addr;
 }
+EXPORT_SYMBOL_GPL(advance_nextseg);
 
-static void lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
-			   u32 tbl_id)
+void lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
+		    u32 tbl_id)
 {
 	struct net *net = dev_net(skb->dev);
 	struct ipv6hdr *hdr = ipv6_hdr(skb);
@@ -188,6 +190,7 @@ static void lookup_nexthop(struct sk_buff *skb, struct in6_addr *nhaddr,
 	skb_dst_drop(skb);
 	skb_dst_set(skb, dst);
 }
+EXPORT_SYMBOL_GPL(lookup_nexthop);
 
 /* regular endpoint function */
 static int input_action_end(struct sk_buff *skb, struct seg6_local_lwt *slwt)
-- 
2.1.4

Re: [net-next] ipv6: sr: export some functions of seg6local

[David Lebrun]

On 12/29/2017 09:09 PM, Ahmed Abdelsalam wrote:
> Some functions of seg6local are very useful to process SRv6
> encapsulated packets.
> 
> This patch exports some functions of seg6local that are useful and
> can be re-used at different parts of the kernel.
> 
> The set of exported functions are:
> (1) get_srh()
> (2) advance_nextseg()
> (3) lookup_nexthop

If you want to export those functions, it's better to prefix them with
e.g. seg6_:

seg6_get_srh()
seg6_advance_nextseg()
seg6_lookup_nexthop()

David

Re: [net-next] ipv6: sr: export some functions of seg6local

[Ahmed Abdelsalam]

Ok! 
Thanks David
On Tue, 2 Jan 2018 20:11:48 +0000
David Lebrun <dav.lebrun@gmail.com> wrote:

> On 12/29/2017 09:09 PM, Ahmed Abdelsalam wrote:
> > Some functions of seg6local are very useful to process SRv6
> > encapsulated packets.
> > 
> > This patch exports some functions of seg6local that are useful and
> > can be re-used at different parts of the kernel.
> > 
> > The set of exported functions are:
> > (1) get_srh()
> > (2) advance_nextseg()
> > (3) lookup_nexthop
> 
> If you want to export those functions, it's better to prefix them with
> e.g. seg6_:
> 
> seg6_get_srh()
> seg6_advance_nextseg()
> seg6_lookup_nexthop()
> 
> David


-- 
Ahmed Abdelsalam <amsalam20@gmail.com>