From feb4900c25deabaf9b54760e40aea5e65499e987 Mon Sep 17 00:00:00 2001 From: Laurent Vivier Date: Wed, 6 Mar 2024 16:58:35 +1100 Subject: checksum: use csum_ip4_header() in udp.c and tcp.c We can find the same function to compute the IPv4 header checksum in tcp.c, udp.c and tap.c Use the function defined for tap.c, csum_ip4_header(), but with the code used in tcp.c and udp.c as it doesn't need a fully initialiazed IPv4 header, only protocol, tot_len, saddr and daddr. Signed-off-by: Laurent Vivier Reviewed-by: David Gibson Message-ID: <20240303135114.1023026-7-lvivier@redhat.com> [dwg: Fix weird cppcheck regression; it appears to be a problem in pre-existing code, but somehow this patch is exposing it] Signed-off-by: David Gibson Signed-off-by: Stefano Brivio --- udp.c | 20 ++------------------ 1 file changed, 2 insertions(+), 18 deletions(-) (limited to 'udp.c') diff --git a/udp.c b/udp.c index 2b41a1b..fb8373b 100644 --- a/udp.c +++ b/udp.c @@ -275,23 +275,6 @@ static void udp_invert_portmap(struct udp_fwd_ports *fwd) } } -/** - * udp_update_check4() - Update checksum with variable parts from stored one - * @buf: L2 packet buffer with final IPv4 header - */ -static void udp_update_check4(struct udp4_l2_buf_t *buf) -{ - uint32_t sum = L2_BUF_IP4_PSUM(IPPROTO_UDP); - - sum += buf->iph.tot_len; - sum += (buf->iph.saddr >> 16) & 0xffff; - sum += buf->iph.saddr & 0xffff; - sum += (buf->iph.daddr >> 16) & 0xffff; - sum += buf->iph.daddr & 0xffff; - - buf->iph.check = (uint16_t)~csum_fold(sum); -} - /** * udp_update_l2_buf() - Update L2 buffers with Ethernet and IPv4 addresses * @eth_d: Ethernet destination address, NULL if unchanged @@ -619,7 +602,8 @@ static size_t udp_update_hdr4(const struct ctx *c, int n, in_port_t dstport, } b->iph.saddr = src->s_addr; - udp_update_check4(b); + b->iph.check = csum_ip4_header(b->iph.tot_len, IPPROTO_UDP, + *src, c->ip4.addr_seen); b->uh.source = b->s_in.sin_port; b->uh.dest = htons(dstport); b->uh.len = htons(udp4_l2_mh_sock[n].msg_len + sizeof(b->uh)); -- cgit v1.2.3