/*
 * netsniff-ng - the packet sniffing beast
 * Copyright 2009, 2010 Daniel Borkmann.
 * Subject to the GPL, version 2.
 */

#include <stdio.h>
#include <stdint.h>
#include <endian.h>
#include <netinet/in.h>    /* for ntohs() */
#include <asm/byteorder.h>

#include "proto.h"
#include "protos.h"
#include "lookup.h"
#include "built_in.h"
#include "pkt_buff.h"

struct tcphdr {
	uint16_t source;
	uint16_t dest;
	uint32_t seq;
	uint32_t ack_seq;
#if defined(__LITTLE_ENDIAN_BITFIELD)
	__extension__ uint16_t res1:4,
			       doff:4,
			       fin:1,
			       syn:1,
			       rst:1,
			       psh:1,
			       ack:1,
			       urg:1,
			       ece:1,
			       cwr:1;
#elif defined(__BIG_ENDIAN_BITFIELD)
	__extension__ uint16_t doff:4,
			       res1:4,
			       cwr:1,
			       ece:1,
			       urg:1,
			       ack:1,
			       psh:1,
			       rst:1,
			       syn:1,
			       fin:1;
#else
# error  "Adjust your <asm/byteorder.h> defines"
#endif
	uint16_t window;
	uint16_t check;
	uint16_t urg_ptr;
} __packed;

#define tprintf_flag(flag, str, prev)	({		\
	bool __r = false;					\
	if (flag) {					\
		tprintf("%s%s", (prev) ? " " : "", str);	\
		__r = true;					\
	}							\
	__r;							\
})

static void tcp(struct pkt_buff *pkt)
{
	struct tcphdr *tcp = (struct tcphdr *) pkt_pull(pkt, sizeof(*tcp));
	uint16_t src, dest;
	const char *src_name, *dest_name;
	bool v = false;

	if (tcp == NULL)
		return;

	src = ntohs(tcp->source);
	dest = ntohs(tcp->dest);

	src_name = lookup_port_tcp(src);
	dest_name = lookup_port_tcp(dest);

	tprintf(" [ TCP ");
	tprintf("Port (%u", src);
	if (src_name)
		tprintf(" (%s%s%s)", colorize_start(bold), src_name,
			colorize_end());
	tprintf(" => %u", dest);
	if (dest_name)
		tprintf(" (%s%s%s)", colorize_start(bold), dest_name,
			colorize_end());
	tprintf("), ");
	tprintf("SN (0x%x), ", ntohl(tcp->seq));
	tprintf("AN (0x%x), ", ntohl(tcp->ack_seq));
	tprintf("DataOff (%u), ", tcp->doff);
	tprintf("Res (%u), ", tcp->res1);
	tprintf("Flags (");
	v = tprintf_flag(tcp->fin, "FIN", v);
	v = tprintf_flag(tcp->syn, "SYN", v);
	v = tprintf_flag(tcp->rst, "RST", v);
	v = tprintf_flag(tcp->psh, "PSH", v);
	v = tprintf_flag(tcp->ack, "ACK", v);
	v = tprintf_flag(tcp->urg, "URG", v);
	v = tprintf_flag(tcp->ece, "ECE", v);
	v = tprintf_flag(tcp->cwr, "CWR", v);
	tprintf("), ");
	tprintf("Window (%u), ", ntohs(tcp->window));
	tprintf("CSum (0x%.4x), ", ntohs(tcp->check));
	tprintf("UrgPtr (%u)", ntohs(tcp->urg_ptr));
	tprintf(" ]\n");
}

static void tcp_less(struct pkt_buff *pkt)
{
	struct tcphdr *tcp = (struct tcphdr *) pkt_pull(pkt, sizeof(*tcp));
	uint16_t src, dest;
	const char *src_name, *dest_name;

	if (tcp == NULL)
		return;

	src = ntohs(tcp->source);
	dest = ntohs(tcp->dest);

	src_name = lookup_port_tcp(src);
	dest_name = lookup_port_tcp(dest);

	tprintf(" TCP %u", src);
	if(src_name)
		tprintf("(%s%s%s)", colorize_start(bold), src_name,
			colorize_end());
	tprintf("/%u", dest);
	if(dest_name)
		tprintf("(%s%s%s)", colorize_start(bold), dest_name,
			colorize_end());
	tprintf(" F%s",colorize_start(bold));
	if (tcp->fin)
		tprintf(" FIN");
	if (tcp->syn)
		tprintf(" SYN");
	if (tcp->rst)
		tprintf(" RST");
	if (tcp->psh)
		tprintf(" PSH");
	if (tcp->ack)
		tprintf(" ACK");
	if (tcp->urg)
		tprintf(" URG");
	if (tcp->ece)
		tprintf(" ECE");
	if (tcp->cwr)
		tprintf(" CWR");
	tprintf("%s Win %u S/A 0x%x/0x%x", colorize_end(),
		ntohs(tcp->window), ntohl(tcp->seq), ntohl(tcp->ack_seq));
}

struct protocol tcp_ops = {
	.key = 0x06,
	.print_full = tcp,
	.print_less = tcp_less,
};
'>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><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Liping Zhang &lt;liping.zhang@spreadtrum.com&gt;</td><td class='right'>2016-09-17 14:31:20 +0800</td></tr>
<tr><th>committer</th><td>Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;</td><td class='right'>2016-09-23 09:30:26 +0200</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=a20877b5edec4d2b62560b5245199af04846476c'>a20877b5edec4d2b62560b5245199af04846476c</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=a20877b5edec4d2b62560b5245199af04846476c'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=a20877b5edec4d2b62560b5245199af04846476c'>da43d9f571eb5a6c41b013645c831564e2f7b534</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?h=nds-private-remove&amp;id=8dc3c2b86bb16e8f345b80a8af69696e9a7edb65'>8dc3c2b86bb16e8f345b80a8af69696e9a7edb65</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=a20877b5edec4d2b62560b5245199af04846476c&amp;id2=8dc3c2b86bb16e8f345b80a8af69696e9a7edb65'>diff</a>)</td></tr></table>
<div class='commit-subject'>netfilter: nf_tables: check tprot_set first when we use xt.thoff</div><div class='commit-msg'>pkt-&gt;xt.thoff is not always set properly, but we use it without any check.
For payload expr, it will cause wrong results. For nftrace, we may notify
the wrong network or transport header to the user space, furthermore,
input the following nft rules, warning message will be printed out:
  # nft add rule arp filter output meta nftrace set 1

  WARNING: CPU: 0 PID: 13428 at net/netfilter/nf_tables_trace.c:263
  nft_trace_notify+0x4a3/0x5e0 [nf_tables]
  Call Trace:
  [&lt;ffffffff813d58ae&gt;] dump_stack+0x63/0x85
  [&lt;ffffffff810a4c0b&gt;] __warn+0xcb/0xf0
  [&lt;ffffffff810a4d3d&gt;] warn_slowpath_null+0x1d/0x20
  [&lt;ffffffffa0589703&gt;] nft_trace_notify+0x4a3/0x5e0 [nf_tables]
  [ ... ]
  [&lt;ffffffffa05690a8&gt;] nft_do_chain_arp+0x78/0x90 [nf_tables_arp]
  [&lt;ffffffff816f4aa2&gt;] nf_iterate+0x62/0x80
  [&lt;ffffffff816f4b33&gt;] nf_hook_slow+0x73/0xd0
  [&lt;ffffffff81732bbf&gt;] arp_xmit+0x8f/0xb0
  [ ... ]
  [&lt;ffffffff81732d36&gt;] arp_solicit+0x106/0x2c0

So before we use pkt-&gt;xt.thoff, check the tprot_set first.

Signed-off-by: Liping Zhang &lt;liping.zhang@spreadtrum.com&gt;
Signed-off-by: Pablo Neira Ayuso &lt;pablo@netfilter.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=a20877b5edec4d2b62560b5245199af04846476c'>Diffstat</a></div><table summary='diffstat' class='diffstat'>