/*
 * Copyright (C) 2016 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
 */

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/cryptohash.h>
#include <linux/module.h>
#include <linux/cache.h>
#include <linux/random.h>
#include <linux/hrtimer.h>
#include <linux/ktime.h>
#include <linux/string.h>
#include <linux/net.h>
#include <linux/siphash.h>
#include <net/secure_seq.h>

#if IS_ENABLED(CONFIG_IPV6) || IS_ENABLED(CONFIG_INET)
#include <linux/in6.h>
#include <net/tcp.h>

static siphash_key_t net_secret __read_mostly;

static __always_inline void net_secret_init(void)
{
	net_get_random_once(&net_secret, sizeof(net_secret));
}
#endif

#ifdef CONFIG_INET
static u32 seq_scale(u32 seq)
{
	/*
	 *	As close as possible to RFC 793, which
	 *	suggests using a 250 kHz clock.
	 *	Further reading shows this assumes 2 Mb/s networks.
	 *	For 10 Mb/s Ethernet, a 1 MHz clock is appropriate.
	 *	For 10 Gb/s Ethernet, a 1 GHz clock should be ok, but
	 *	we also need to limit the resolution so that the u32 seq
	 *	overlaps less than one time per MSL (2 minutes).
	 *	Choosing a clock of 64 ns period is OK. (period of 274 s)
	 */
	return seq + (ktime_get_real_ns() >> 6);
}
#endif

#if IS_ENABLED(CONFIG_IPV6)
u32 secure_tcpv6_sequence_number(const __be32 *saddr, const __be32 *daddr,
				 __be16 sport, __be16 dport, u32 *tsoff)
{
	const struct {
		struct in6_addr saddr;
		struct in6_addr daddr;
		__be16 sport;
		__be16 dport;
	} __aligned(SIPHASH_ALIGNMENT) combined = {
		.saddr = *(struct in6_addr *)saddr,
		.daddr = *(struct in6_addr *)daddr,
		.sport = sport,
		.dport = dport
	};
	u64 hash;
	net_secret_init();
	hash = siphash(&combined, offsetofend(typeof(combined), dport),
		       &net_secret);
	*tsoff = sysctl_tcp_timestamps == 1 ? (hash >> 32) : 0;
	return seq_scale(hash);
}
EXPORT_SYMBOL(secure_tcpv6_sequence_number);

u32 secure_ipv6_port_ephemeral(const __be32 *saddr, const __be32 *daddr,
			       __be16 dport)
{
	const struct {
		struct in6_addr saddr;
		struct in6_addr daddr;
		__be16 dport;
	} __aligned(SIPHASH_ALIGNMENT) combined = {
		.saddr = *(struct in6_addr *)saddr,
		.daddr = *(struct in6_addr *)daddr,
		.dport = dport
	};
	net_secret_init();
	return siphash(&combined, offsetofend(typeof(combined), dport),
		       &net_secret);
}
EXPORT_SYMBOL(secure_ipv6_port_ephemeral);
#endif

#ifdef CONFIG_INET

/* secure_tcp_sequence_number(a, b, 0, d) == secure_ipv4_port_ephemeral(a, b, d),
 * but fortunately, `sport' cannot be 0 in any circumstances. If this changes,
 * it would be easy enough to have the former function use siphash_4u32, passing
 * the arguments as separate u32.
 */

u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
			       __be16 sport, __be16 dport, u32 *tsoff)
{
	u64 hash;
	net_secret_init();
	hash = siphash_3u32((__force u32)saddr, (__force u32)daddr,
			    (__force u32)sport << 16 | (__force u32)dport,
			    &net_secret);
	*tsoff = sysctl_tcp_timestamps == 1 ? (hash >> 32) : 0;
	return seq_scale(hash);
}

u32 secure_ipv4_port_ephemeral(__be32 saddr, __be32 daddr, __be16 dport)
{
	net_secret_init();
	return siphash_3u32((__force u32)saddr, (__force u32)daddr,
			    (__force u16)dport, &net_secret);
}
EXPORT_SYMBOL_GPL(secure_ipv4_port_ephemeral);
#endif

#if IS_ENABLED(CONFIG_IP_DCCP)
u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr,
				__be16 sport, __be16 dport)
{
	u64 seq;
	net_secret_init();
	seq = siphash_3u32(saddr, daddr, (u32)sport << 16 | dport, &net_secret);
	seq += ktime_get_real_ns();
	seq &= (1ull << 48) - 1;
	return seq;
}
EXPORT_SYMBOL(secure_dccp_sequence_number);

#if IS_ENABLED(CONFIG_IPV6)
u64 secure_dccpv6_sequence_number(__be32 *saddr, __be32 *daddr,
				  __be16 sport, __be16 dport)
{
	const struct {
		struct in6_addr saddr;
		struct in6_addr daddr;
		__be16 sport;
		__be16 dport;
	} __aligned(SIPHASH_ALIGNMENT) combined = {
		.saddr = *(struct in6_addr *)saddr,
		.daddr = *(struct in6_addr *)daddr,
		.sport = sport,
		.dport = dport
	};
	u64 seq;
	net_secret_init();
	seq = siphash(&combined, offsetofend(typeof(combined), dport),
		      &net_secret);
	seq += ktime_get_real_ns();
	seq &= (1ull << 48) - 1;
	return seq;
}
EXPORT_SYMBOL(secure_dccpv6_sequence_number);
#endif
#endif
ubmit();'><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>Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;</td><td class='right'>2017-02-03 22:19:15 +0100</td></tr>
<tr><th>committer</th><td>Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;</td><td class='right'>2017-02-03 22:19:15 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/xfrm/Kconfig?id=424414947da3dd5cb0d60e4f299f7c51e472ae77'>424414947da3dd5cb0d60e4f299f7c51e472ae77</a> (<a href='/cgit.cgi/linux/net-next.git/patch/net/xfrm/Kconfig?id=424414947da3dd5cb0d60e4f299f7c51e472ae77'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=424414947da3dd5cb0d60e4f299f7c51e472ae77'>a4067480c4256c80ae8f8438a3e4bb88e32050bc</a> /<a href='/cgit.cgi/linux/net-next.git/tree/net/xfrm/Kconfig?id=424414947da3dd5cb0d60e4f299f7c51e472ae77'>net/xfrm/Kconfig</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/xfrm/Kconfig?id=a3683e0c1410c5c8136a7a93b0336ce88d3b893a'>a3683e0c1410c5c8136a7a93b0336ce88d3b893a</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/xfrm/Kconfig?id=424414947da3dd5cb0d60e4f299f7c51e472ae77&amp;id2=a3683e0c1410c5c8136a7a93b0336ce88d3b893a'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/net/xfrm/Kconfig?id=d07830db1bdb254e4b50d366010b219286b8c937'>d07830db1bdb254e4b50d366010b219286b8c937</a> (<a href='/cgit.cgi/linux/net-next.git/diff/net/xfrm/Kconfig?id=424414947da3dd5cb0d60e4f299f7c51e472ae77&amp;id2=d07830db1bdb254e4b50d366010b219286b8c937'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge tag 'usb-serial-4.10-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-linus</div><div class='commit-msg'>Johan writes:

USB-serial fixes for v4.10-rc7

One more device ID for pl2303.

Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=424414947da3dd5cb0d60e4f299f7c51e472ae77'>Diffstat</a> (limited to 'net/xfrm/Kconfig')</div><table summary='diffstat' class='diffstat'>