From 336d3262df71fcd2661180bb35d5ea41b4cbca58 Mon Sep 17 00:00:00 2001 From: Harvey Harrison Date: Fri, 18 Jul 2008 23:07:09 -0700 Subject: [PATCH] sctp: remove unnecessary byteshifting, calculate directly in big-endian Signed-off-by: Harvey Harrison Signed-off-by: Vlad Yasevich Signed-off-by: David S. Miller --- include/net/sctp/checksum.h | 23 ++++++++++++++--------- net/ipv4/netfilter/nf_nat_proto_sctp.c | 4 ++-- net/sctp/input.c | 4 ++-- net/sctp/output.c | 4 ++-- 4 files changed, 20 insertions(+), 15 deletions(-) diff --git a/include/net/sctp/checksum.h b/include/net/sctp/checksum.h index ba75c67cb992..b799fb21519a 100644 --- a/include/net/sctp/checksum.h +++ b/include/net/sctp/checksum.h @@ -46,9 +46,14 @@ #include #include -static inline __u32 sctp_start_cksum(__u8 *buffer, __u16 length) +static inline __be32 sctp_crc32c(__be32 crc, u8 *buffer, u16 length) { - __u32 crc = ~(__u32) 0; + return (__force __be32)crc32c((__force u32)crc, buffer, length); +} + +static inline __be32 sctp_start_cksum(__u8 *buffer, __u16 length) +{ + __be32 crc = ~cpu_to_be32(0); __u8 zero[sizeof(__u32)] = {0}; /* Optimize this routine to be SCTP specific, knowing how @@ -56,23 +61,23 @@ static inline __u32 sctp_start_cksum(__u8 *buffer, __u16 length) */ /* Calculate CRC up to the checksum. */ - crc = crc32c(crc, buffer, sizeof(struct sctphdr) - sizeof(__u32)); + crc = sctp_crc32c(crc, buffer, sizeof(struct sctphdr) - sizeof(__u32)); /* Skip checksum field of the header. */ - crc = crc32c(crc, zero, sizeof(__u32)); + crc = sctp_crc32c(crc, zero, sizeof(__u32)); /* Calculate the rest of the CRC. */ - crc = crc32c(crc, &buffer[sizeof(struct sctphdr)], + crc = sctp_crc32c(crc, &buffer[sizeof(struct sctphdr)], length - sizeof(struct sctphdr)); return crc; } -static inline __u32 sctp_update_cksum(__u8 *buffer, __u16 length, __u32 crc32) +static inline __be32 sctp_update_cksum(__u8 *buffer, __u16 length, __be32 crc32) { - return crc32c(crc32, buffer, length); + return sctp_crc32c(crc32, buffer, length); } -static inline __u32 sctp_end_cksum(__u32 crc32) +static inline __be32 sctp_end_cksum(__be32 crc32) { - return ntohl(~crc32); + return ~crc32; } diff --git a/net/ipv4/netfilter/nf_nat_proto_sctp.c b/net/ipv4/netfilter/nf_nat_proto_sctp.c index 82e4c0e286b8..65e470bc6123 100644 --- a/net/ipv4/netfilter/nf_nat_proto_sctp.c +++ b/net/ipv4/netfilter/nf_nat_proto_sctp.c @@ -36,7 +36,7 @@ sctp_manip_pkt(struct sk_buff *skb, sctp_sctphdr_t *hdr; unsigned int hdroff = iphdroff + iph->ihl*4; __be32 oldip, newip; - u32 crc32; + __be32 crc32; if (!skb_make_writable(skb, hdroff + sizeof(*hdr))) return false; @@ -61,7 +61,7 @@ sctp_manip_pkt(struct sk_buff *skb, crc32 = sctp_update_cksum((u8 *)skb->data, skb_headlen(skb), crc32); crc32 = sctp_end_cksum(crc32); - hdr->checksum = htonl(crc32); + hdr->checksum = crc32; return true; } diff --git a/net/sctp/input.c b/net/sctp/input.c index 5ed93c05c23e..a49fa80b57b9 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -83,8 +83,8 @@ static inline int sctp_rcv_checksum(struct sk_buff *skb) { struct sk_buff *list = skb_shinfo(skb)->frag_list; struct sctphdr *sh = sctp_hdr(skb); - __u32 cmp = ntohl(sh->checksum); - __u32 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); + __be32 cmp = sh->checksum; + __be32 val = sctp_start_cksum((__u8 *)sh, skb_headlen(skb)); for (; list; list = list->next) val = sctp_update_cksum((__u8 *)list->data, skb_headlen(list), diff --git a/net/sctp/output.c b/net/sctp/output.c index 9a63a3fb9011..45684646b1db 100644 --- a/net/sctp/output.c +++ b/net/sctp/output.c @@ -365,7 +365,7 @@ int sctp_packet_transmit(struct sctp_packet *packet) struct sctp_transport *tp = packet->transport; struct sctp_association *asoc = tp->asoc; struct sctphdr *sh; - __u32 crc32 = 0; + __be32 crc32 = __constant_cpu_to_be32(0); struct sk_buff *nskb; struct sctp_chunk *chunk, *tmp; struct sock *sk; @@ -538,7 +538,7 @@ int sctp_packet_transmit(struct sctp_packet *packet) /* 3) Put the resultant value into the checksum field in the * common header, and leave the rest of the bits unchanged. */ - sh->checksum = htonl(crc32); + sh->checksum = crc32; /* IP layer ECN support * From RFC 2481 -- 2.20.1