Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 024ec3de authored by Joe Stringer's avatar Joe Stringer Committed by David S. Miller
Browse files

net/sctp: Refactor SCTP skb checksum computation 



This patch consolidates the SCTP checksum calculation code from various
places to a single new function, sctp_compute_cksum(skb, offset).

Signed-off-by: default avatarJoe Stringer <joe@wand.net.nz>
Reviewed-by: default avatarJulian Anastasov <ja@ssi.bg>
Acked-by: default avatarSimon Horman <horms@verge.net.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e7428e95

include/net/sctp/checksum.h

+15 −0
Original line number Diff line number Diff line
@@ -85,4 +85,19 @@ static inline __le32 sctp_end_cksum(__u32 crc32) 
	return cpu_to_le32(~crc32);

}



/* Calculate the CRC32C checksum of an SCTP packet.  */

static inline __le32 sctp_compute_cksum(const struct sk_buff *skb,

					unsigned int offset)

{

	const struct sk_buff *iter;



	__u32 crc32 = sctp_start_cksum(skb->data + offset,

				       skb_headlen(skb) - offset);

	skb_walk_frags(skb, iter)

		crc32 = sctp_update_cksum((__u8 *) iter->data,

					  skb_headlen(iter), crc32);



	return sctp_end_cksum(crc32);

}



#endif /* __sctp_checksum_h__ */

net/netfilter/ipvs/ip_vs_proto_sctp.c

+3 −20
Original line number Diff line number Diff line
@@ -66,15 +66,7 @@ sctp_conn_schedule(int af, struct sk_buff *skb, struct ip_vs_proto_data *pd, 
static void sctp_nat_csum(struct sk_buff *skb, sctp_sctphdr_t *sctph,

			  unsigned int sctphoff)

{

	__u32 crc32;

	struct sk_buff *iter;



	crc32 = sctp_start_cksum((__u8 *)sctph, skb_headlen(skb) - sctphoff);

	skb_walk_frags(skb, iter)

		crc32 = sctp_update_cksum((u8 *) iter->data,

					  skb_headlen(iter), crc32);

	sctph->checksum = sctp_end_cksum(crc32);



	sctph->checksum = sctp_compute_cksum(skb, sctphoff);

	skb->ip_summed = CHECKSUM_UNNECESSARY;

}
@@ -151,10 +143,7 @@ sctp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp) 
{

	unsigned int sctphoff;

	struct sctphdr *sh, _sctph;

	struct sk_buff *iter;

	__le32 cmp;

	__le32 val;

	__u32 tmp;

	__le32 cmp, val;



#ifdef CONFIG_IP_VS_IPV6

	if (af == AF_INET6)
@@ -168,13 +157,7 @@ sctp_csum_check(int af, struct sk_buff *skb, struct ip_vs_protocol *pp) 
		return 0;



	cmp = sh->checksum;



	tmp = sctp_start_cksum((__u8 *) sh, skb_headlen(skb));

	skb_walk_frags(skb, iter)

		tmp = sctp_update_cksum((__u8 *) iter->data,

					skb_headlen(iter), tmp);



	val = sctp_end_cksum(tmp);

	val = sctp_compute_cksum(skb, sctphoff);



	if (val != cmp) {

		/* CRC failure, dump it. */

net/netfilter/nf_nat_proto_sctp.c

+1 −7
Original line number Diff line number Diff line
@@ -34,9 +34,7 @@ sctp_manip_pkt(struct sk_buff *skb, 
	       const struct nf_conntrack_tuple *tuple,

	       enum nf_nat_manip_type maniptype)

{

	struct sk_buff *frag;

	sctp_sctphdr_t *hdr;

	__u32 crc32;



	if (!skb_make_writable(skb, hdroff + sizeof(*hdr)))

		return false;
@@ -51,11 +49,7 @@ sctp_manip_pkt(struct sk_buff *skb, 
		hdr->dest = tuple->dst.u.sctp.port;

	}



	crc32 = sctp_start_cksum((u8 *)hdr, skb_headlen(skb) - hdroff);

	skb_walk_frags(skb, frag)

		crc32 = sctp_update_cksum((u8 *)frag->data, skb_headlen(frag),

					  crc32);

	hdr->checksum = sctp_end_cksum(crc32);

	hdr->checksum = sctp_compute_cksum(skb, hdroff);



	return true;

}

net/sctp/input.c

+1 −9
Original line number Diff line number Diff line
@@ -87,15 +87,7 @@ static inline int sctp_rcv_checksum(struct net *net, struct sk_buff *skb) 
{

	struct sctphdr *sh = sctp_hdr(skb);

	__le32 cmp = sh->checksum;

	struct sk_buff *list;

	__le32 val;

	__u32 tmp = sctp_start_cksum((__u8 *)sh, skb_headlen(skb));



	skb_walk_frags(skb, list)

		tmp = sctp_update_cksum((__u8 *)list->data, skb_headlen(list),

					tmp);



	val = sctp_end_cksum(tmp);

	__le32 val = sctp_compute_cksum(skb, 0);



	if (val != cmp) {

		/* CRC failure, dump it. */