Helper function bpf_tcp_check_syncookie
Definition
Copyright (c) 2015 The Libbpf Authors. All rights reserved.
Check whether iph and th contain a valid SYN cookie ACK for the listening socket in sk.
iph points to the start of the IPv4 or IPv6 header, while iph_len contains sizeof(struct iphdr) or sizeof(struct ipv6hdr).
th points to the start of the TCP header, while th_len contains the length of the TCP header (at least sizeof(struct tcphdr)).
Returns
0 if iph and th are a valid SYN cookie ACK, or a negative error otherwise.
static long (* const bpf_tcp_check_syncookie)(void *sk, void *iph, __u32 iph_len, struct tcphdr *th, __u32 th_len) = (void *) 100;
Usage
Docs could be improved
This part of the docs is incomplete, contributions are very welcome
Program types
This helper call can be used in the following program types:
Example
Docs could be improved
This part of the docs is incomplete, contributions are very welcome