/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Copyright Tomi Manninen OH2BNS (oh2bns@sral.fi)
 */
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include <linux/timer.h>
#include <net/ax25.h>
#include <linux/skbuff.h>
#include <net/netrom.h>
#include <linux/init.h>

static void nr_loopback_timer(unsigned long);

static struct sk_buff_head loopback_queue;
static DEFINE_TIMER(loopback_timer, nr_loopback_timer, 0, 0);

void __init nr_loopback_init(void)
{
	skb_queue_head_init(&loopback_queue);
}

static inline int nr_loopback_running(void)
{
	return timer_pending(&loopback_timer);
}

int nr_loopback_queue(struct sk_buff *skb)
{
	struct sk_buff *skbn;

	if ((skbn = alloc_skb(skb->len, GFP_ATOMIC)) != NULL) {
		skb_copy_from_linear_data(skb, skb_put(skbn, skb->len), skb->len);
		skb_reset_transport_header(skbn);

		skb_queue_tail(&loopback_queue, skbn);

		if (!nr_loopback_running())
			mod_timer(&loopback_timer, jiffies + 10);
	}

	kfree_skb(skb);
	return 1;
}

static void nr_loopback_timer(unsigned long param)
{
	struct sk_buff *skb;
	ax25_address *nr_dest;
	struct net_device *dev;

	if ((skb = skb_dequeue(&loopback_queue)) != NULL) {
		nr_dest = (ax25_address *)(skb->data + 7);

		dev = nr_dev_get(nr_dest);

		if (dev == NULL || nr_rx_frame(skb, dev) == 0)
			kfree_skb(skb);

		if (dev != NULL)
			dev_put(dev);

		if (!skb_queue_empty(&loopback_queue) && !nr_loopback_running())
			mod_timer(&loopback_timer, jiffies + 10);
	}
}

void __exit nr_loopback_clear(void)
{
	del_timer_sync(&loopback_timer);
	skb_queue_purge(&loopback_queue);
}
cgi/linux/net-next.git/commit/?id=2d18ac4ba7454a4260473e68be7e485ae71e7948'>commit</a><a href='/cgit.cgi/linux/net-next.git/diff/?id=2d18ac4ba7454a4260473e68be7e485ae71e7948'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/'>
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<div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='2d18ac4ba7454a4260473e68be7e485ae71e7948'/><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><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Jon Paul Maloy &lt;jon.maloy@ericsson.com&gt;</td><td class='right'>2016-07-11 16:08:35 -0400</td></tr>
<tr><th>committer</th><td>David S. Miller &lt;davem@davemloft.net&gt;</td><td class='right'>2016-07-11 22:42:12 -0700</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=2d18ac4ba7454a4260473e68be7e485ae71e7948'>2d18ac4ba7454a4260473e68be7e485ae71e7948</a> (<a href='/cgit.cgi/linux/net-next.git/patch/?id=2d18ac4ba7454a4260473e68be7e485ae71e7948'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=2d18ac4ba7454a4260473e68be7e485ae71e7948'>0e31dd046751711ac548b9db6027e36495306e08</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/?id=34ee32c9a5696247be405bb0c21f3d1fc6cb5729'>34ee32c9a5696247be405bb0c21f3d1fc6cb5729</a> (<a href='/cgit.cgi/linux/net-next.git/diff/?id=2d18ac4ba7454a4260473e68be7e485ae71e7948&amp;id2=34ee32c9a5696247be405bb0c21f3d1fc6cb5729'>diff</a>)</td></tr></table>
<div class='commit-subject'>tipc: extend broadcast link initialization criteria</div><div class='commit-msg'>At first contact between two nodes, an endpoint might sometimes have
time to send out a LINK_PROTOCOL/STATE packet before it has received
the broadcast initialization packet from the peer, i.e., before it has
received a valid broadcast packet number to add to the 'bc_ack' field
of the protocol message.

This means that the peer endpoint will receive a protocol packet with an
invalid broadcast acknowledge value of 0. Under unlucky circumstances
this may lead to the original, already received acknowledge value being
overwritten, so that the whole broadcast link goes stale after a while.

We fix this by delaying the setting of the link field 'bc_peer_is_up'
until we know that the peer really has received our own broadcast
initialization message. The latter is always sent out as the first
unicast message on a link, and always with seqeunce number 1. Because
of this, we only need to look for a non-zero unicast acknowledge value
in the arriving STATE messages, and once that is confirmed we know we
are safe and can set the mentioned field. Before this moment, we must
ignore all broadcast acknowledges from the peer.

Acked-by: Ying Xue &lt;ying.xue@windriver.com&gt;
Signed-off-by: Jon Maloy &lt;jon.maloy@ericsson.com&gt;
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=2d18ac4ba7454a4260473e68be7e485ae71e7948'>Diffstat</a></div><table summary='diffstat' class='diffstat'>