/* Copyright (c) 2016 Facebook
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 */
#define KBUILD_MODNAME "foo"
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/in.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <uapi/linux/bpf.h>
#include <net/ip.h>
#include "bpf_helpers.h"

#define DEFAULT_PKTGEN_UDP_PORT 9

/* copy of 'struct ethhdr' without __packed */
struct eth_hdr {
	unsigned char   h_dest[ETH_ALEN];
	unsigned char   h_source[ETH_ALEN];
	unsigned short  h_proto;
};

SEC("simple")
int handle_ingress(struct __sk_buff *skb)
{
	void *data = (void *)(long)skb->data;
	struct eth_hdr *eth = data;
	struct iphdr *iph = data + sizeof(*eth);
	struct udphdr *udp = data + sizeof(*eth) + sizeof(*iph);
	void *data_end = (void *)(long)skb->data_end;

	/* single length check */
	if (data + sizeof(*eth) + sizeof(*iph) + sizeof(*udp) > data_end)
		return 0;

	if (eth->h_proto != htons(ETH_P_IP))
		return 0;
	if (iph->protocol != IPPROTO_UDP || iph->ihl != 5)
		return 0;
	if (ip_is_fragment(iph))
		return 0;
	if (udp->dest == htons(DEFAULT_PKTGEN_UDP_PORT))
		return TC_ACT_SHOT;
	return 0;
}
char _license[] SEC("license") = "GPL";
cket-loop-back'>packet-loop-back</option>
<option value='packet-rx-pump-back'>packet-rx-pump-back</option>
</select> <input type='submit' value='switch'/></form></td></tr>
<tr><td class='sub'>net-next plumbings</td><td class='sub right'>Tobias Klauser</td></tr></table>
<table class='tabs'><tr><td>
<a href='/cgit.cgi/linux/net-next.git/'>summary</a><a href='/cgit.cgi/linux/net-next.git/refs/?id=206c4720092d2a24bfefc041b377e889a220ffbf'>refs</a><a href='/cgit.cgi/linux/net-next.git/log/net/ax25/ax25_uid.c'>log</a><a href='/cgit.cgi/linux/net-next.git/tree/net/ax25/ax25_uid.c?id=206c4720092d2a24bfefc041b377e889a220ffbf'>tree</a><a href='/cgit.cgi/linux/net-next.git/commit/net/ax25/ax25_uid.c?id=206c4720092d2a24bfefc041b377e889a220ffbf'>commit</a><a class='active' href='/cgit.cgi/linux/net-next.git/diff/net/ax25/ax25_uid.c?id=206c4720092d2a24bfefc041b377e889a220ffbf&amp;id2=b98acbff9a05b371c5f0ca6e44a3af8ce9274379'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/net/ax25/ax25_uid.c'>
<input type='hidden' name='id' value='206c4720092d2a24bfefc041b377e889a220ffbf'/><input type='hidden' name='id2' value='b98acbff9a05b371c5f0ca6e44a3af8ce9274379'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/diff/?id=206c4720092d2a24bfefc041b377e889a220ffbf&amp;id2=b98acbff9a05b371c5f0ca6e44a3af8ce9274379'>root</a>/<a href='/cgit.cgi/linux/net-next.git/diff/net?id=206c4720092d2a24bfefc041b377e889a220ffbf&amp;id2=b98acbff9a05b371c5f0ca6e44a3af8ce9274379'>net</a>/<a href='/cgit.cgi/linux/net-next.git/diff/net/ax25?id=206c4720092d2a24bfefc041b377e889a220ffbf&amp;id2=b98acbff9a05b371c5f0ca6e44a3af8ce9274379'>ax25</a>/<a href='/cgit.cgi/linux/net-next.git/diff/net/ax25/ax25_uid.c?id=206c4720092d2a24bfefc041b377e889a220ffbf&amp;id2=b98acbff9a05b371c5f0ca6e44a3af8ce9274379'>ax25_uid.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='206c4720092d2a24bfefc041b377e889a220ffbf'/><input type='hidden' name='id2' value='b98acbff9a05b371c5f0ca6e44a3af8ce9274379'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=206c4720092d2a24bfefc041b377e889a220ffbf&amp;id2=b98acbff9a05b371c5f0ca6e44a3af8ce9274379'>Diffstat</a> (limited to 'net/ax25/ax25_uid.c')</div><table summary='diffstat' class='diffstat'>