passt/checksum.h
David Gibson bd4be308fc Add csum_udp4() helper for calculating UDP over IPv4 checksums
At least two places in passt fill in UDP over IPv4 checksums, although
since UDP checksums are optional with IPv4 that just amounts to storing
a 0 (in tap_ip_send()) or leaving a 0 from an earlier initialization (in
dhcp()).  For consistency, add a helper for this "calculation".

Just for the heck of it, add the option (compile time disabled for now) to
calculate real UDP checksums.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
2022-10-19 03:34:32 +02:00

28 lines
962 B
C

/* SPDX-License-Identifier: AGPL-3.0-or-later
* Copyright (c) 2021 Red Hat GmbH
* Author: Stefano Brivio <sbrivio@redhat.com>
*/
#ifndef CHECKSUM_H
#define CHECKSUM_H
struct udphdr;
struct icmphdr;
struct icmp6hdr;
uint32_t sum_16b(const void *buf, size_t len);
uint16_t csum_fold(uint32_t sum);
uint16_t csum_unaligned(const void *buf, size_t len, uint32_t init);
void csum_udp4(struct udphdr *udp4hr, in_addr_t saddr, in_addr_t daddr,
const void *payload, size_t len);
void csum_icmp4(struct icmphdr *ih, const void *payload, size_t len);
void csum_udp6(struct udphdr *udp6hr,
const struct in6_addr *saddr, const struct in6_addr *daddr,
const void *payload, size_t len);
void csum_icmp6(struct icmp6hdr *icmp6hr,
const struct in6_addr *saddr, const struct in6_addr *daddr,
const void *payload, size_t len);
void csum_tcp4(struct iphdr *iph);
uint16_t csum(const void *buf, size_t len, uint32_t init);
#endif /* CHECKSUM_H */