371 	struct tcphdr *tcp;  member
397 		hdr->tcp = (void *)hdr->ipv4 + hdr->ipv4->ihl * 4;  in tcp_dissect()
414 		hdr->tcp = (void *)hdr->ipv6 + sizeof(*hdr->ipv6);  in tcp_dissect()
421 	if (hdr->tcp + 1 > data_end)  in tcp_dissect()
423 	hdr->tcp_len = hdr->tcp->doff * 4;  in tcp_dissect()
424 	if (hdr->tcp_len < sizeof(*hdr->tcp))  in tcp_dissect()
441 		/* TCP doesn't normally use fragments, and XDP can't reassemble  in tcp_lookup()
449 		tup.ipv4.sport = hdr->tcp->source;  in tcp_lookup()
450 		tup.ipv4.dport = hdr->tcp->dest;  in tcp_lookup()
455 		tup.ipv6.sport = hdr->tcp->source;  in tcp_lookup()
456 		tup.ipv6.dport = hdr->tcp->dest;  in tcp_lookup()
552 	tcp_gen_synack(hdr->tcp, cookie, tsopt, mss, wscale);  in tcpv4_gen_synack()
554 	hdr->tcp_len = hdr->tcp->doff * 4;  in tcpv4_gen_synack()
573 	tcp_gen_synack(hdr->tcp, cookie, tsopt, mss, wscale);  in tcpv6_gen_synack()
575 	hdr->tcp_len = hdr->tcp->doff * 4;  in tcpv6_gen_synack()
607 	/* Checksum is not yet verified, but both checksum failure and TCP  in syncookie_handle_syn()
610 	if (hdr->tcp->fin || hdr->tcp->rst)  in syncookie_handle_syn()
616 	if (!check_port_allowed(bpf_ntohs(hdr->tcp->dest)))  in syncookie_handle_syn()
620 		/* Check the IPv4 and TCP checksums before creating a SYNACK. */  in syncookie_handle_syn()
627 		value = bpf_csum_diff(0, 0, (void *)hdr->tcp, hdr->tcp_len, 0);  in syncookie_handle_syn()
632 			return XDP_DROP; /* Bad TCP checksum. */  in syncookie_handle_syn()
636 		value = bpf_tcp_raw_gen_syncookie_ipv4(hdr->ipv4, hdr->tcp,  in syncookie_handle_syn()
639 		/* Check the TCP checksum before creating a SYNACK. */  in syncookie_handle_syn()
640 		value = bpf_csum_diff(0, 0, (void *)hdr->tcp, hdr->tcp_len, 0);  in syncookie_handle_syn()
645 			return XDP_DROP; /* Bad TCP checksum. */  in syncookie_handle_syn()
649 		value = bpf_tcp_raw_gen_syncookie_ipv6(hdr->ipv6, hdr->tcp,  in syncookie_handle_syn()
659 	if (tscookie_init((void *)hdr->tcp, hdr->tcp_len,  in syncookie_handle_syn()
675 			__builtin_memmove(new_tcp_header, hdr->tcp, sizeof(*hdr->tcp));  in syncookie_handle_syn()
676 			hdr->tcp = new_tcp_header;  in syncookie_handle_syn()
689 	hdr->tcp->check = 0;  in syncookie_handle_syn()
690 	value = bpf_csum_diff(0, 0, (void *)hdr->tcp, hdr->tcp_len, 0);  in syncookie_handle_syn()
694 		hdr->tcp->check = csum_tcpudp_magic(hdr->ipv4->saddr,  in syncookie_handle_syn()
706 		hdr->tcp->check = csum_ipv6_magic(&hdr->ipv6->saddr,  in syncookie_handle_syn()
717 	new_pkt_size = sizeof(*hdr->eth) + ip_len + hdr->tcp->doff * 4;  in syncookie_handle_syn()
735 	if (hdr->tcp->rst)  in syncookie_handle_ack()
739 		err = bpf_tcp_raw_check_syncookie_ipv4(hdr->ipv4, hdr->tcp);  in syncookie_handle_ack()
741 		err = bpf_tcp_raw_check_syncookie_ipv6(hdr->ipv6, hdr->tcp);  in syncookie_handle_ack()
763 	/* Packet is TCP and doesn't belong to an established connection. */  in syncookie_part1()
765 	if ((hdr->tcp->syn ^ hdr->tcp->ack) != 1)  in syncookie_part1()
768 	/* Grow the TCP header to TCP_MAXLEN to be able to pass any hdr->tcp_len  in syncookie_part1()
798 		hdr->tcp = (void *)hdr->ipv4 + hdr->ipv4->ihl * 4;  in syncookie_part2()
802 		hdr->tcp = (void *)hdr->ipv6 + sizeof(*hdr->ipv6);  in syncookie_part2()
807 	if ((void *)hdr->tcp + TCP_MAXLEN > data_end)  in syncookie_part2()
813 	hdr->tcp_len = hdr->tcp->doff * 4;  in syncookie_part2()
814 	if (hdr->tcp_len < sizeof(*hdr->tcp))  in syncookie_part2()
817 	return hdr->tcp->syn ? syncookie_handle_syn(hdr, ctx, data, data_end, xdp) :  in syncookie_part2()