/*
 * llc_station.c - station component of LLC
 *
 * Copyright (c) 1997 by Procom Technology, Inc.
 * 		 2001-2003 by Arnaldo Carvalho de Melo <acme@conectiva.com.br>
 *
 * This program can be redistributed or modified under the terms of the
 * GNU General Public License as published by the Free Software Foundation.
 * This program is distributed without any warranty or implied warranty
 * of merchantability or fitness for a particular purpose.
 *
 * See the GNU General Public License for more details.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <net/llc.h>
#include <net/llc_sap.h>
#include <net/llc_conn.h>
#include <net/llc_c_ac.h>
#include <net/llc_s_ac.h>
#include <net/llc_c_ev.h>
#include <net/llc_c_st.h>
#include <net/llc_s_ev.h>
#include <net/llc_s_st.h>
#include <net/llc_pdu.h>

static int llc_stat_ev_rx_null_dsap_xid_c(struct sk_buff *skb)
{
	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);

	return LLC_PDU_IS_CMD(pdu) &&			/* command PDU */
	       LLC_PDU_TYPE_IS_U(pdu) &&		/* U type PDU */
	       LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_XID &&
	       !pdu->dsap ? 0 : 1;			/* NULL DSAP value */
}

static int llc_stat_ev_rx_null_dsap_test_c(struct sk_buff *skb)
{
	struct llc_pdu_un *pdu = llc_pdu_un_hdr(skb);

	return LLC_PDU_IS_CMD(pdu) &&			/* command PDU */
	       LLC_PDU_TYPE_IS_U(pdu) &&		/* U type PDU */
	       LLC_U_PDU_CMD(pdu) == LLC_1_PDU_CMD_TEST &&
	       !pdu->dsap ? 0 : 1;			/* NULL DSAP */
}

static int llc_station_ac_send_xid_r(struct sk_buff *skb)
{
	u8 mac_da[ETH_ALEN], dsap;
	int rc = 1;
	struct sk_buff *nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U,
					       sizeof(struct llc_xid_info));

	if (!nskb)
		goto out;
	rc = 0;
	llc_pdu_decode_sa(skb, mac_da);
	llc_pdu_decode_ssap(skb, &dsap);
	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
	llc_pdu_init_as_xid_rsp(nskb, LLC_XID_NULL_CLASS_2, 127);
	rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
	if (unlikely(rc))
		goto free;
	dev_queue_xmit(nskb);
out:
	return rc;
free:
	kfree_skb(nskb);
	goto out;
}

static int llc_station_ac_send_test_r(struct sk_buff *skb)
{
	u8 mac_da[ETH_ALEN], dsap;
	int rc = 1;
	u32 data_size;
	struct sk_buff *nskb;

	/* The test request command is type U (llc_len = 3) */
	data_size = ntohs(eth_hdr(skb)->h_proto) - 3;
	nskb = llc_alloc_frame(NULL, skb->dev, LLC_PDU_TYPE_U, data_size);

	if (!nskb)
		goto out;
	rc = 0;
	llc_pdu_decode_sa(skb, mac_da);
	llc_pdu_decode_ssap(skb, &dsap);
	llc_pdu_header_init(nskb, LLC_PDU_TYPE_U, 0, dsap, LLC_PDU_RSP);
	llc_pdu_init_as_test_rsp(nskb, skb);
	rc = llc_mac_hdr_init(nskb, skb->dev->dev_addr, mac_da);
	if (unlikely(rc))
		goto free;
	dev_queue_xmit(nskb);
out:
	return rc;
free:
	kfree_skb(nskb);
	goto out;
}

/**
 *	llc_station_rcv - send received pdu to the station state machine
 *	@skb: received frame.
 *
 *	Sends data unit to station state machine.
 */
static void llc_station_rcv(struct sk_buff *skb)
{
	if (llc_stat_ev_rx_null_dsap_xid_c(skb))
		llc_station_ac_send_xid_r(skb);
	else if (llc_stat_ev_rx_null_dsap_test_c(skb))
		llc_station_ac_send_test_r(skb);
	kfree_skb(skb);
}

void __init llc_station_init(void)
{
	llc_set_station_handler(llc_station_rcv);
}

void llc_station_exit(void)
{
	llc_set_station_handler(NULL);
}
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><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2017-02-01 11:22:38 -0500</td></tr>
<tr><th>committer</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2017-02-01 11:22:38 -0500</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ipv4/ah4.c?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2'>04cdf13e34e912dcab9a94f391e15b2c26dfd0a2</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/ipv4/ah4.c?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2'>0f0dcf018d5ce2298ed98ec854d6592370a4348a</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/ipv4/ah4.c?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2'>net/ipv4/ah4.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ipv4/ah4.c?id=624374a56419c2d6d428c862f32cc1b20519095d'>624374a56419c2d6d428c862f32cc1b20519095d</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/ipv4/ah4.c?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2&amp;id2=624374a56419c2d6d428c862f32cc1b20519095d'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/ipv4/ah4.c?id=1995876a06bcf6f9f7d7b699bdbf387831679771'>1995876a06bcf6f9f7d7b699bdbf387831679771</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/ipv4/ah4.c?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2&amp;id2=1995876a06bcf6f9f7d7b699bdbf387831679771'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next</div><div class='commit-msg'>Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2017-02-01

1) Some typo fixes, from Alexander Alemayhu.

2) Don't acquire state lock in get_mtu functions.
   The only rece against a dead state does not matter.
   From Florian Westphal.

3) Remove xfrm4_state_fini, it is unused for more than
   10 years. From Florian Westphal.

4) Various rcu usage improvements. From Florian Westphal.

5) Properly handle crypto arrors in ah4/ah6.
   From Gilad Ben-Yossef.

6) Try to avoid skb linearization in esp4 and esp6.

7) The esp trailer is now set up in different places,
   add a helper for this.

8) With the upcomming usage of gro_cells in IPsec,
   a gro merged skb can have a secpath. Drop it
   before freeing or reusing the skb.

9) Add a xfrm dummy network device for napi. With
   this we can use gro_cells from within xfrm,
   it allows IPsec GRO without impact on the generic
   networking code.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2'>Diffstat</a> (limited to 'net/ipv4/ah4.c')</div><table summary='diffstat' class='diffstat'><tr><td class='mode'>-rw-r--r--</td><td class='upd'><a href='/cgit.cgi/linux/net-next.git/diff/net/ipv4/ah4.c?id=04cdf13e34e912dcab9a94f391e15b2c26dfd0a2'>net/ipv4/ah4.c</a></td><td class='right'>3</td><td class='graph'><table summary='file diffstat' width='3%'><tr><td class='add' style='width: 100.0%;'/><td class='rem' style='width: 0.0%;'/><td class='none' style='width: 0.0%;'/></tr></table></td></tr>
</table><div class='diffstat-summary'>1 files changed, 3 insertions, 0 deletions</div><table summary='diff' class='diff'><tr><td><div class='head'>diff --git a/net/ipv4/ah4.c b/net/ipv4/ah4.c