sctp: Clean up sctp checksumming code
The sctp crc32c checksum is always generated in little endian.
So, we clean up the code to treat it as little endian and remove
all the __force casts.
Suggested by Herbert Xu.
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 693fd08..d2e9880 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -83,14 +83,15 @@
{
struct sk_buff *list = skb_shinfo(skb)->frag_list;
struct sctphdr *sh = sctp_hdr(skb);
- __be32 cmp = sh->checksum;
- __be32 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb));
+ __le32 cmp = sh->checksum;
+ __le32 val;
+ __u32 tmp = sctp_start_cksum((__u8 *)sh, skb_headlen(skb));
for (; list; list = list->next)
- val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list),
- val);
+ tmp = sctp_update_cksum((__u8 *)list->data, skb_headlen(list),
+ tmp);
- val = sctp_end_cksum(val);
+ val = sctp_end_cksum(tmp);
if (val != cmp) {
/* CRC failure, dump it. */
diff --git a/net/sctp/output.c b/net/sctp/output.c
index 2d65b7a..07d5890 100644
--- a/net/sctp/output.c
+++ b/net/sctp/output.c
@@ -367,7 +367,6 @@
struct sctp_transport *tp = packet->transport;
struct sctp_association *asoc = tp->asoc;
struct sctphdr *sh;
- __be32 crc32 = cpu_to_be32(0);
struct sk_buff *nskb;
struct sctp_chunk *chunk, *tmp;
struct sock *sk;
@@ -532,16 +531,15 @@
* by CRC32-C as described in <draft-ietf-tsvwg-sctpcsum-02.txt>.
*/
if (!sctp_checksum_disable && !(dst->dev->features & NETIF_F_NO_CSUM)) {
- crc32 = sctp_start_cksum((__u8 *)sh, cksum_buf_len);
- crc32 = sctp_end_cksum(crc32);
+ __u32 crc32 = sctp_start_cksum((__u8 *)sh, cksum_buf_len);
+
+ /* 3) Put the resultant value into the checksum field in the
+ * common header, and leave the rest of the bits unchanged.
+ */
+ sh->checksum = sctp_end_cksum(crc32);
} else
nskb->ip_summed = CHECKSUM_UNNECESSARY;
- /* 3) Put the resultant value into the checksum field in the
- * common header, and leave the rest of the bits unchanged.
- */
- sh->checksum = crc32;
-
/* IP layer ECN support
* From RFC 2481
* "The ECN-Capable Transport (ECT) bit would be set by the