Commit fa55a7d7 authored by Andrew Lunn's avatar Andrew Lunn Committed by David S. Miller
Browse files

seg6: export get_srh() for ICMP handling 



An ICMP error message can contain in its message body part of an IPv6
packet which invoked the error. Such a packet might contain a segment
router header. Export get_srh() so the ICMP code can make use of it.

Since his changes the scope of the function from local to global, add
the seg6_ prefix to keep the namespace clean. And move it into seg6.c
so it is always available, not just when IPV6_SEG6_LWTUNNEL is
enabled.

Signed-off-by: default avatarAndrew Lunn <andrew@lunn.ch>
Reviewed-by: default avatarDavid Ahern <dsahern@kernel.org>
Reviewed-by: default avatarWillem de Bruijn <willemb@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e8fe9e83

include/net/seg6.h

+1 −0
Original line number Diff line number Diff line
@@ -58,6 +58,7 @@ extern int seg6_local_init(void); 
extern void seg6_local_exit(void);



extern bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len, bool reduced);

extern struct ipv6_sr_hdr *seg6_get_srh(struct sk_buff *skb, int flags);

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);

net/ipv6/seg6.c

+29 −0
Original line number Diff line number Diff line
@@ -75,6 +75,35 @@ bool seg6_validate_srh(struct ipv6_sr_hdr *srh, int len, bool reduced) 
	return true;

}



struct ipv6_sr_hdr *seg6_get_srh(struct sk_buff *skb, int flags)

{

	struct ipv6_sr_hdr *srh;

	int len, srhoff = 0;



	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, &flags) < 0)

		return NULL;



	if (!pskb_may_pull(skb, srhoff + sizeof(*srh)))

		return NULL;



	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);



	len = (srh->hdrlen + 1) << 3;



	if (!pskb_may_pull(skb, srhoff + len))

		return NULL;



	/* note that pskb_may_pull may change pointers in header;

	 * for this reason it is necessary to reload them when needed.

	 */

	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);



	if (!seg6_validate_srh(srh, len, true))

		return NULL;



	return srh;

}



static struct genl_family seg6_genl_family;



static const struct nla_policy seg6_genl_policy[SEG6_ATTR_MAX + 1] = {

net/ipv6/seg6_local.c

+2 −31
Original line number Diff line number Diff line
@@ -150,40 +150,11 @@ 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, int flags)

{

	struct ipv6_sr_hdr *srh;

	int len, srhoff = 0;



	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, &flags) < 0)

		return NULL;



	if (!pskb_may_pull(skb, srhoff + sizeof(*srh)))

		return NULL;



	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);



	len = (srh->hdrlen + 1) << 3;



	if (!pskb_may_pull(skb, srhoff + len))

		return NULL;



	/* note that pskb_may_pull may change pointers in header;

	 * for this reason it is necessary to reload them when needed.

	 */

	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);



	if (!seg6_validate_srh(srh, len, true))

		return NULL;



	return srh;

}



static struct ipv6_sr_hdr *get_and_validate_srh(struct sk_buff *skb)

{

	struct ipv6_sr_hdr *srh;



	srh = get_srh(skb, IP6_FH_F_SKIP_RH);

	srh = seg6_get_srh(skb, IP6_FH_F_SKIP_RH);

	if (!srh)

		return NULL;
@@ -200,7 +171,7 @@ static bool decap_and_validate(struct sk_buff *skb, int proto) 
	struct ipv6_sr_hdr *srh;

	unsigned int off = 0;



	srh = get_srh(skb, 0);

	srh = seg6_get_srh(skb, 0);

	if (srh && srh->segments_left > 0)

		return false;