[linux-block.git] / net / rxrpc / peer_event.c

/* Peer event handling, typically ICMP messages.
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * 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.
 */

#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/errqueue.h>
#include <linux/udp.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/icmp.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <net/ip.h>
#include "ar-internal.h"

static void rxrpc_store_error(struct rxrpc_peer *, struct sock_exterr_skb *);

/*
 * Find the peer associated with an ICMP packet.
 */
static struct rxrpc_peer *rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local *local,
						     const struct sk_buff *skb)
{
	struct sock_exterr_skb *serr = SKB_EXT_ERR(skb);
	struct sockaddr_rxrpc srx;

	_enter("");

	memset(&srx, 0, sizeof(srx));
	srx.transport_type = local->srx.transport_type;
	srx.transport_len = local->srx.transport_len;
	srx.transport.family = local->srx.transport.family;

	/* Can we see an ICMP4 packet on an ICMP6 listening socket?  and vice
	 * versa?
	 */
	switch (srx.transport.family) {
	case AF_INET:
		srx.transport.sin.sin_port = serr->port;
		switch (serr->ee.ee_origin) {
		case SO_EE_ORIGIN_ICMP:
			_net("Rx ICMP");
			memcpy(&srx.transport.sin.sin_addr,
			       skb_network_header(skb) + serr->addr_offset,
			       sizeof(struct in_addr));
			break;
		case SO_EE_ORIGIN_ICMP6:
			_net("Rx ICMP6 on v4 sock");
			memcpy(&srx.transport.sin.sin_addr,
			       skb_network_header(skb) + serr->addr_offset + 12,
			       sizeof(struct in_addr));
			break;
		default:
			memcpy(&srx.transport.sin.sin_addr, &ip_hdr(skb)->saddr,
			       sizeof(struct in_addr));
			break;
		}
		break;

#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		srx.transport.sin6.sin6_port = serr->port;
		switch (serr->ee.ee_origin) {
		case SO_EE_ORIGIN_ICMP6:
			_net("Rx ICMP6");
			memcpy(&srx.transport.sin6.sin6_addr,
			       skb_network_header(skb) + serr->addr_offset,
			       sizeof(struct in6_addr));
			break;
		case SO_EE_ORIGIN_ICMP:
			_net("Rx ICMP on v6 sock");
			srx.transport.sin6.sin6_addr.s6_addr32[0] = 0;
			srx.transport.sin6.sin6_addr.s6_addr32[1] = 0;
			srx.transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
			memcpy(srx.transport.sin6.sin6_addr.s6_addr + 12,
			       skb_network_header(skb) + serr->addr_offset,
			       sizeof(struct in_addr));
			break;
		default:
			memcpy(&srx.transport.sin6.sin6_addr,
			       &ipv6_hdr(skb)->saddr,
			       sizeof(struct in6_addr));
			break;
		}
		break;
#endif

	default:
		BUG();
	}

	return rxrpc_lookup_peer_rcu(local, &srx);
}

/*
 * Handle an MTU/fragmentation problem.
 */
static void rxrpc_adjust_mtu(struct rxrpc_peer *peer, struct sock_exterr_skb *serr)
{
	u32 mtu = serr->ee.ee_info;

	_net("Rx ICMP Fragmentation Needed (%d)", mtu);

	/* wind down the local interface MTU */
	if (mtu > 0 && peer->if_mtu == 65535 && mtu < peer->if_mtu) {
		peer->if_mtu = mtu;
		_net("I/F MTU %u", mtu);
	}

	if (mtu == 0) {
		/* they didn't give us a size, estimate one */
		mtu = peer->if_mtu;
		if (mtu > 1500) {
			mtu >>= 1;
			if (mtu < 1500)
				mtu = 1500;
		} else {
			mtu -= 100;
			if (mtu < peer->hdrsize)
				mtu = peer->hdrsize + 4;
		}
	}

	if (mtu < peer->mtu) {
		spin_lock_bh(&peer->lock);
		peer->mtu = mtu;
		peer->maxdata = peer->mtu - peer->hdrsize;
		spin_unlock_bh(&peer->lock);
		_net("Net MTU %u (maxdata %u)",
		     peer->mtu, peer->maxdata);
	}
}

/*
 * Handle an error received on the local endpoint.
 */
void rxrpc_error_report(struct sock *sk)
{
	struct sock_exterr_skb *serr;
	struct rxrpc_local *local = sk->sk_user_data;
	struct rxrpc_peer *peer;
	struct sk_buff *skb;

	_enter("%p{%d}", sk, local->debug_id);

	skb = sock_dequeue_err_skb(sk);
	if (!skb) {
		_leave("UDP socket errqueue empty");
		return;
	}
	rxrpc_new_skb(skb, rxrpc_skb_rx_received);
	serr = SKB_EXT_ERR(skb);
	if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) {
		_leave("UDP empty message");
		rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
		return;
	}

	rcu_read_lock();
	peer = rxrpc_lookup_peer_icmp_rcu(local, skb);
	if (peer && !rxrpc_get_peer_maybe(peer))
		peer = NULL;
	if (!peer) {
		rcu_read_unlock();
		rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
		_leave(" [no peer]");
		return;
	}

	if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP &&
	     serr->ee.ee_type == ICMP_DEST_UNREACH &&
	     serr->ee.ee_code == ICMP_FRAG_NEEDED)) {
		rxrpc_adjust_mtu(peer, serr);
		rcu_read_unlock();
		rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
		rxrpc_put_peer(peer);
		_leave(" [MTU update]");
		return;
	}

	rxrpc_store_error(peer, serr);
	rcu_read_unlock();
	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);

	/* The ref we obtained is passed off to the work item */
	__rxrpc_queue_peer_error(peer);
	_leave("");
}

/*
 * Map an error report to error codes on the peer record.
 */
static void rxrpc_store_error(struct rxrpc_peer *peer,
			      struct sock_exterr_skb *serr)
{
	struct sock_extended_err *ee;
	int err;

	_enter("");

	ee = &serr->ee;

	_net("Rx Error o=%d t=%d c=%d e=%d",
	     ee->ee_origin, ee->ee_type, ee->ee_code, ee->ee_errno);

	err = ee->ee_errno;

	switch (ee->ee_origin) {
	case SO_EE_ORIGIN_ICMP:
		switch (ee->ee_type) {
		case ICMP_DEST_UNREACH:
			switch (ee->ee_code) {
			case ICMP_NET_UNREACH:
				_net("Rx Received ICMP Network Unreachable");
				break;
			case ICMP_HOST_UNREACH:
				_net("Rx Received ICMP Host Unreachable");
				break;
			case ICMP_PORT_UNREACH:
				_net("Rx Received ICMP Port Unreachable");
				break;
			case ICMP_NET_UNKNOWN:
				_net("Rx Received ICMP Unknown Network");
				break;
			case ICMP_HOST_UNKNOWN:
				_net("Rx Received ICMP Unknown Host");
				break;
			default:
				_net("Rx Received ICMP DestUnreach code=%u",
				     ee->ee_code);
				break;
			}
			break;

		case ICMP_TIME_EXCEEDED:
			_net("Rx Received ICMP TTL Exceeded");
			break;

		default:
			_proto("Rx Received ICMP error { type=%u code=%u }",
			       ee->ee_type, ee->ee_code);
			break;
		}
		break;

	case SO_EE_ORIGIN_NONE:
	case SO_EE_ORIGIN_LOCAL:
		_proto("Rx Received local error { error=%d }", err);
		err += RXRPC_LOCAL_ERROR_OFFSET;
		break;

	case SO_EE_ORIGIN_ICMP6:
	default:
		_proto("Rx Received error report { orig=%u }", ee->ee_origin);
		break;
	}

	peer->error_report = err;
}

/*
 * Distribute an error that occurred on a peer
 */
void rxrpc_peer_error_distributor(struct work_struct *work)
{
	struct rxrpc_peer *peer =
		container_of(work, struct rxrpc_peer, error_distributor);
	struct rxrpc_call *call;
	enum rxrpc_call_completion compl;
	int error;

	_enter("");

	error = READ_ONCE(peer->error_report);
	if (error < RXRPC_LOCAL_ERROR_OFFSET) {
		compl = RXRPC_CALL_NETWORK_ERROR;
	} else {
		compl = RXRPC_CALL_LOCAL_ERROR;
		error -= RXRPC_LOCAL_ERROR_OFFSET;
	}

	_debug("ISSUE ERROR %s %d", rxrpc_call_completions[compl], error);

	spin_lock_bh(&peer->lock);

	while (!hlist_empty(&peer->error_targets)) {
		call = hlist_entry(peer->error_targets.first,
				   struct rxrpc_call, error_link);
		hlist_del_init(&call->error_link);
		rxrpc_see_call(call);

		if (rxrpc_set_call_completion(call, compl, 0, -error))
			rxrpc_notify_socket(call);
	}

	spin_unlock_bh(&peer->lock);

	rxrpc_put_peer(peer);
	_leave("");
}

/*
 * Add RTT information to cache.  This is called in softirq mode and has
 * exclusive access to the peer RTT data.
 */
void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
			rxrpc_serial_t send_serial, rxrpc_serial_t resp_serial,
			ktime_t send_time, ktime_t resp_time)
{
	struct rxrpc_peer *peer = call->peer;
	s64 rtt;
	u64 sum = peer->rtt_sum, avg;
	u8 cursor = peer->rtt_cursor, usage = peer->rtt_usage;

	rtt = ktime_to_ns(ktime_sub(resp_time, send_time));
	if (rtt < 0)
		return;

	/* Replace the oldest datum in the RTT buffer */
	sum -= peer->rtt_cache[cursor];
	sum += rtt;
	peer->rtt_cache[cursor] = rtt;
	peer->rtt_cursor = (cursor + 1) & (RXRPC_RTT_CACHE_SIZE - 1);
	peer->rtt_sum = sum;
	if (usage < RXRPC_RTT_CACHE_SIZE) {
		usage++;
		peer->rtt_usage = usage;
	}

	/* Now recalculate the average */
	if (usage == RXRPC_RTT_CACHE_SIZE) {
		avg = sum / RXRPC_RTT_CACHE_SIZE;
	} else {
		avg = sum;
		do_div(avg, usage);
	}

	peer->rtt = avg;
	trace_rxrpc_rtt_rx(call, why, send_serial, resp_serial, rtt,
			   usage, avg);
}

/*
 * Perform keep-alive pings with VERSION packets to keep any NAT alive.
 */
void rxrpc_peer_keepalive_worker(struct work_struct *work)
{
	struct rxrpc_net *rxnet =
		container_of(work, struct rxrpc_net, peer_keepalive_work);
	struct rxrpc_peer *peer;
	unsigned long delay;
	ktime_t base, now = ktime_get_real();
	s64 diff;
	u8 cursor, slot;

	base = rxnet->peer_keepalive_base;
	cursor = rxnet->peer_keepalive_cursor;

	_enter("%u,%lld", cursor, ktime_sub(now, base));

next_bucket:
	diff = ktime_to_ns(ktime_sub(now, base));
	if (diff < 0)
		goto resched;

	_debug("at %u", cursor);
	spin_lock_bh(&rxnet->peer_hash_lock);
next_peer:
	if (!rxnet->live) {
		spin_unlock_bh(&rxnet->peer_hash_lock);
		goto out;
	}

	/* Everything in the bucket at the cursor is processed this second; the
	 * bucket at cursor + 1 goes now + 1s and so on...
	 */
	if (hlist_empty(&rxnet->peer_keepalive[cursor])) {
		if (hlist_empty(&rxnet->peer_keepalive_new)) {
			spin_unlock_bh(&rxnet->peer_hash_lock);
			goto emptied_bucket;
		}

		hlist_move_list(&rxnet->peer_keepalive_new,
				&rxnet->peer_keepalive[cursor]);
	}

	peer = hlist_entry(rxnet->peer_keepalive[cursor].first,
			   struct rxrpc_peer, keepalive_link);
	hlist_del_init(&peer->keepalive_link);
	if (!rxrpc_get_peer_maybe(peer))
		goto next_peer;

	spin_unlock_bh(&rxnet->peer_hash_lock);

	_debug("peer %u {%pISp}", peer->debug_id, &peer->srx.transport);

recalc:
	diff = ktime_divns(ktime_sub(peer->last_tx_at, base), NSEC_PER_SEC);
	if (diff < -30 || diff > 30)
		goto send; /* LSW of 64-bit time probably wrapped on 32-bit */
	diff += RXRPC_KEEPALIVE_TIME - 1;
	if (diff < 0)
		goto send;

	slot = (diff > RXRPC_KEEPALIVE_TIME - 1) ? RXRPC_KEEPALIVE_TIME - 1 : diff;
	if (slot == 0)
		goto send;

	/* A transmission to this peer occurred since last we examined it so
	 * put it into the appropriate future bucket.
	 */
	slot = (slot + cursor) % ARRAY_SIZE(rxnet->peer_keepalive);
	spin_lock_bh(&rxnet->peer_hash_lock);
	hlist_add_head(&peer->keepalive_link, &rxnet->peer_keepalive[slot]);
	rxrpc_put_peer(peer);
	goto next_peer;

send:
	rxrpc_send_keepalive(peer);
	now = ktime_get_real();
	goto recalc;

emptied_bucket:
	cursor++;
	if (cursor >= ARRAY_SIZE(rxnet->peer_keepalive))
		cursor = 0;
	base = ktime_add_ns(base, NSEC_PER_SEC);
	goto next_bucket;

resched:
	rxnet->peer_keepalive_base = base;
	rxnet->peer_keepalive_cursor = cursor;
	delay = nsecs_to_jiffies(-diff) + 1;
	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay);
out:
	_leave("");
}
Commit	Line	Data
f66d7490	1	/* Peer event handling, typically ICMP messages.
17926a79 DH	2	*
	3	* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
	4	* Written by David Howells (dhowells@redhat.com)
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11
	12	#include <linux/module.h>
	13	#include <linux/net.h>
	14	#include <linux/skbuff.h>
	15	#include <linux/errqueue.h>
	16	#include <linux/udp.h>
	17	#include <linux/in.h>
	18	#include <linux/in6.h>
	19	#include <linux/icmp.h>
	20	#include <net/sock.h>
	21	#include <net/af_rxrpc.h>
	22	#include <net/ip.h>
	23	#include "ar-internal.h"
	24
f66d7490 DH	25	static void rxrpc_store_error(struct rxrpc_peer , struct sock_exterr_skb );
f66d7490 DH	26
be6e6707 DH	27	/*
	28	* Find the peer associated with an ICMP packet.
	29	*/
	30	static struct rxrpc_peer rxrpc_lookup_peer_icmp_rcu(struct rxrpc_local local,
	31	const struct sk_buff *skb)
	32	{
	33	struct sock_exterr_skb *serr = SKB_EXT_ERR(skb);
	34	struct sockaddr_rxrpc srx;
	35
	36	_enter("");
	37
	38	memset(&srx, 0, sizeof(srx));
	39	srx.transport_type = local->srx.transport_type;
7b674e39	40	srx.transport_len = local->srx.transport_len;
be6e6707 DH	41	srx.transport.family = local->srx.transport.family;
	42
	43	/* Can we see an ICMP4 packet on an ICMP6 listening socket? and vice
	44	* versa?
	45	*/
	46	switch (srx.transport.family) {
	47	case AF_INET:
	48	srx.transport.sin.sin_port = serr->port;
be6e6707 DH	49	switch (serr->ee.ee_origin) {
	50	case SO_EE_ORIGIN_ICMP:
	51	_net("Rx ICMP");
	52	memcpy(&srx.transport.sin.sin_addr,
	53	skb_network_header(skb) + serr->addr_offset,
	54	sizeof(struct in_addr));
	55	break;
	56	case SO_EE_ORIGIN_ICMP6:
	57	_net("Rx ICMP6 on v4 sock");
	58	memcpy(&srx.transport.sin.sin_addr,
	59	skb_network_header(skb) + serr->addr_offset + 12,
	60	sizeof(struct in_addr));
	61	break;
	62	default:
	63	memcpy(&srx.transport.sin.sin_addr, &ip_hdr(skb)->saddr,
	64	sizeof(struct in_addr));
	65	break;
	66	}
	67	break;
	68
d1912747	69	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	70	case AF_INET6:
75b54cb5 DH	71	srx.transport.sin6.sin6_port = serr->port;
75b54cb5 DH	72	switch (serr->ee.ee_origin) {
	73	case SO_EE_ORIGIN_ICMP6:
	74	_net("Rx ICMP6");
	75	memcpy(&srx.transport.sin6.sin6_addr,
	76	skb_network_header(skb) + serr->addr_offset,
	77	sizeof(struct in6_addr));
	78	break;
	79	case SO_EE_ORIGIN_ICMP:
	80	_net("Rx ICMP on v6 sock");
7b674e39 DH	81	srx.transport.sin6.sin6_addr.s6_addr32[0] = 0;
	82	srx.transport.sin6.sin6_addr.s6_addr32[1] = 0;
	83	srx.transport.sin6.sin6_addr.s6_addr32[2] = htonl(0xffff);
d1912747	84	memcpy(srx.transport.sin6.sin6_addr.s6_addr + 12,
75b54cb5 DH	85	skb_network_header(skb) + serr->addr_offset,
	86	sizeof(struct in_addr));
	87	break;
	88	default:
	89	memcpy(&srx.transport.sin6.sin6_addr,
	90	&ipv6_hdr(skb)->saddr,
	91	sizeof(struct in6_addr));
	92	break;
	93	}
	94	break;
d1912747	95	#endif
75b54cb5	96
be6e6707 DH	97	default:
	98	BUG();
	99	}
	100
	101	return rxrpc_lookup_peer_rcu(local, &srx);
	102	}
	103
1a70c05b DH	104	/*
	105	* Handle an MTU/fragmentation problem.
	106	*/
	107	static void rxrpc_adjust_mtu(struct rxrpc_peer peer, struct sock_exterr_skb serr)
	108	{
	109	u32 mtu = serr->ee.ee_info;
	110
	111	_net("Rx ICMP Fragmentation Needed (%d)", mtu);
	112
	113	/* wind down the local interface MTU */
	114	if (mtu > 0 && peer->if_mtu == 65535 && mtu < peer->if_mtu) {
	115	peer->if_mtu = mtu;
	116	_net("I/F MTU %u", mtu);
	117	}
	118
	119	if (mtu == 0) {
	120	/* they didn't give us a size, estimate one */
	121	mtu = peer->if_mtu;
	122	if (mtu > 1500) {
	123	mtu >>= 1;
	124	if (mtu < 1500)
	125	mtu = 1500;
	126	} else {
	127	mtu -= 100;
	128	if (mtu < peer->hdrsize)
	129	mtu = peer->hdrsize + 4;
	130	}
	131	}
	132
	133	if (mtu < peer->mtu) {
	134	spin_lock_bh(&peer->lock);
	135	peer->mtu = mtu;
	136	peer->maxdata = peer->mtu - peer->hdrsize;
	137	spin_unlock_bh(&peer->lock);
	138	_net("Net MTU %u (maxdata %u)",
	139	peer->mtu, peer->maxdata);
	140	}
	141	}
	142
17926a79	143	/*
f66d7490	144	* Handle an error received on the local endpoint.
17926a79	145	*/
abe89ef0	146	void rxrpc_error_report(struct sock *sk)
17926a79 DH	147	{
17926a79 DH	148	struct sock_exterr_skb *serr;
17926a79 DH	149	struct rxrpc_local *local = sk->sk_user_data;
	150	struct rxrpc_peer *peer;
	151	struct sk_buff *skb;
17926a79 DH	152
	153	_enter("%p{%d}", sk, local->debug_id);
	154
364a9e93	155	skb = sock_dequeue_err_skb(sk);
17926a79 DH	156	if (!skb) {
	157	_leave("UDP socket errqueue empty");
	158	return;
	159	}
71f3ca40	160	rxrpc_new_skb(skb, rxrpc_skb_rx_received);
c247f053 WB	161	serr = SKB_EXT_ERR(skb);
c247f053 WB	162	if (!skb->len && serr->ee.ee_origin == SO_EE_ORIGIN_TIMESTAMPING) {
49ca0d8b	163	_leave("UDP empty message");
71f3ca40	164	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
49ca0d8b WB	165	return;
49ca0d8b WB	166	}
17926a79	167
be6e6707 DH	168	rcu_read_lock();
	169	peer = rxrpc_lookup_peer_icmp_rcu(local, skb);
	170	if (peer && !rxrpc_get_peer_maybe(peer))
	171	peer = NULL;
	172	if (!peer) {
	173	rcu_read_unlock();
71f3ca40	174	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
17926a79 DH	175	_leave(" [no peer]");
	176	return;
	177	}
	178
1a70c05b DH	179	if ((serr->ee.ee_origin == SO_EE_ORIGIN_ICMP &&
	180	serr->ee.ee_type == ICMP_DEST_UNREACH &&
	181	serr->ee.ee_code == ICMP_FRAG_NEEDED)) {
	182	rxrpc_adjust_mtu(peer, serr);
f66d7490	183	rcu_read_unlock();
71f3ca40	184	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
f66d7490 DH	185	rxrpc_put_peer(peer);
	186	_leave(" [MTU update]");
	187	return;
17926a79 DH	188	}
17926a79 DH	189
f66d7490	190	rxrpc_store_error(peer, serr);
be6e6707	191	rcu_read_unlock();
71f3ca40	192	rxrpc_free_skb(skb, rxrpc_skb_rx_freed);
17926a79	193
f66d7490	194	/* The ref we obtained is passed off to the work item */
1159d4b4	195	__rxrpc_queue_peer_error(peer);
17926a79 DH	196	_leave("");
	197	}
	198
	199	/*
f66d7490	200	* Map an error report to error codes on the peer record.
17926a79	201	*/
f66d7490 DH	202	static void rxrpc_store_error(struct rxrpc_peer *peer,
f66d7490 DH	203	struct sock_exterr_skb *serr)
17926a79 DH	204	{
17926a79 DH	205	struct sock_extended_err *ee;
c9d10c49	206	int err;
17926a79 DH	207
	208	_enter("");
	209
17926a79 DH	210	ee = &serr->ee;
	211
	212	_net("Rx Error o=%d t=%d c=%d e=%d",
	213	ee->ee_origin, ee->ee_type, ee->ee_code, ee->ee_errno);
	214
	215	err = ee->ee_errno;
	216
	217	switch (ee->ee_origin) {
	218	case SO_EE_ORIGIN_ICMP:
17926a79 DH	219	switch (ee->ee_type) {
	220	case ICMP_DEST_UNREACH:
	221	switch (ee->ee_code) {
	222	case ICMP_NET_UNREACH:
	223	_net("Rx Received ICMP Network Unreachable");
17926a79 DH	224	break;
	225	case ICMP_HOST_UNREACH:
	226	_net("Rx Received ICMP Host Unreachable");
17926a79 DH	227	break;
	228	case ICMP_PORT_UNREACH:
	229	_net("Rx Received ICMP Port Unreachable");
17926a79 DH	230	break;
	231	case ICMP_NET_UNKNOWN:
	232	_net("Rx Received ICMP Unknown Network");
17926a79 DH	233	break;
	234	case ICMP_HOST_UNKNOWN:
	235	_net("Rx Received ICMP Unknown Host");
17926a79 DH	236	break;
	237	default:
	238	_net("Rx Received ICMP DestUnreach code=%u",
	239	ee->ee_code);
	240	break;
	241	}
	242	break;
	243
	244	case ICMP_TIME_EXCEEDED:
	245	_net("Rx Received ICMP TTL Exceeded");
	246	break;
	247
	248	default:
	249	_proto("Rx Received ICMP error { type=%u code=%u }",
	250	ee->ee_type, ee->ee_code);
	251	break;
	252	}
	253	break;
	254
f66d7490	255	case SO_EE_ORIGIN_NONE:
17926a79	256	case SO_EE_ORIGIN_LOCAL:
fe77d5fc	257	_proto("Rx Received local error { error=%d }", err);
f66d7490	258	err += RXRPC_LOCAL_ERROR_OFFSET;
17926a79 DH	259	break;
17926a79 DH	260
17926a79 DH	261	case SO_EE_ORIGIN_ICMP6:
17926a79 DH	262	default:
fe77d5fc	263	_proto("Rx Received error report { orig=%u }", ee->ee_origin);
17926a79 DH	264	break;
	265	}
	266
f66d7490 DH	267	peer->error_report = err;
	268	}
	269
	270	/*
	271	* Distribute an error that occurred on a peer
	272	*/
	273	void rxrpc_peer_error_distributor(struct work_struct *work)
	274	{
	275	struct rxrpc_peer *peer =
	276	container_of(work, struct rxrpc_peer, error_distributor);
	277	struct rxrpc_call *call;
f5c17aae	278	enum rxrpc_call_completion compl;
f5c17aae	279	int error;
f66d7490 DH	280
f66d7490 DH	281	_enter("");
17926a79	282
f5c17aae DH	283	error = READ_ONCE(peer->error_report);
	284	if (error < RXRPC_LOCAL_ERROR_OFFSET) {
	285	compl = RXRPC_CALL_NETWORK_ERROR;
	286	} else {
	287	compl = RXRPC_CALL_LOCAL_ERROR;
	288	error -= RXRPC_LOCAL_ERROR_OFFSET;
	289	}
17926a79	290
f5c17aae	291	_debug("ISSUE ERROR %s %d", rxrpc_call_completions[compl], error);
17926a79	292
f66d7490	293	spin_lock_bh(&peer->lock);
17926a79	294
f66d7490 DH	295	while (!hlist_empty(&peer->error_targets)) {
	296	call = hlist_entry(peer->error_targets.first,
	297	struct rxrpc_call, error_link);
	298	hlist_del_init(&call->error_link);
e34d4234	299	rxrpc_see_call(call);
f66d7490	300
3a92789a	301	if (rxrpc_set_call_completion(call, compl, 0, -error))
248f219c	302	rxrpc_notify_socket(call);
17926a79 DH	303	}
17926a79 DH	304
f66d7490	305	spin_unlock_bh(&peer->lock);
17926a79	306
f66d7490	307	rxrpc_put_peer(peer);
17926a79 DH	308	_leave("");
17926a79 DH	309	}
cf1a6474 DH	310
	311	/*
	312	* Add RTT information to cache. This is called in softirq mode and has
	313	* exclusive access to the peer RTT data.
	314	*/
	315	void rxrpc_peer_add_rtt(struct rxrpc_call *call, enum rxrpc_rtt_rx_trace why,
	316	rxrpc_serial_t send_serial, rxrpc_serial_t resp_serial,
	317	ktime_t send_time, ktime_t resp_time)
	318	{
	319	struct rxrpc_peer *peer = call->peer;
	320	s64 rtt;
	321	u64 sum = peer->rtt_sum, avg;
	322	u8 cursor = peer->rtt_cursor, usage = peer->rtt_usage;
	323
	324	rtt = ktime_to_ns(ktime_sub(resp_time, send_time));
	325	if (rtt < 0)
	326	return;
	327
	328	/* Replace the oldest datum in the RTT buffer */
	329	sum -= peer->rtt_cache[cursor];
	330	sum += rtt;
	331	peer->rtt_cache[cursor] = rtt;
	332	peer->rtt_cursor = (cursor + 1) & (RXRPC_RTT_CACHE_SIZE - 1);
	333	peer->rtt_sum = sum;
	334	if (usage < RXRPC_RTT_CACHE_SIZE) {
	335	usage++;
	336	peer->rtt_usage = usage;
	337	}
	338
	339	/* Now recalculate the average */
	340	if (usage == RXRPC_RTT_CACHE_SIZE) {
	341	avg = sum / RXRPC_RTT_CACHE_SIZE;
	342	} else {
	343	avg = sum;
	344	do_div(avg, usage);
	345	}
	346
	347	peer->rtt = avg;
	348	trace_rxrpc_rtt_rx(call, why, send_serial, resp_serial, rtt,
	349	usage, avg);
	350	}
ace45bec DH	351
	352	/*
	353	* Perform keep-alive pings with VERSION packets to keep any NAT alive.
	354	*/
	355	void rxrpc_peer_keepalive_worker(struct work_struct *work)
	356	{
	357	struct rxrpc_net *rxnet =
	358	container_of(work, struct rxrpc_net, peer_keepalive_work);
	359	struct rxrpc_peer *peer;
	360	unsigned long delay;
	361	ktime_t base, now = ktime_get_real();
	362	s64 diff;
	363	u8 cursor, slot;
	364
	365	base = rxnet->peer_keepalive_base;
	366	cursor = rxnet->peer_keepalive_cursor;
	367
	368	_enter("%u,%lld", cursor, ktime_sub(now, base));
	369
	370	next_bucket:
	371	diff = ktime_to_ns(ktime_sub(now, base));
	372	if (diff < 0)
	373	goto resched;
	374
	375	_debug("at %u", cursor);
	376	spin_lock_bh(&rxnet->peer_hash_lock);
	377	next_peer:
	378	if (!rxnet->live) {
	379	spin_unlock_bh(&rxnet->peer_hash_lock);
	380	goto out;
	381	}
	382
	383	/* Everything in the bucket at the cursor is processed this second; the
	384	* bucket at cursor + 1 goes now + 1s and so on...
	385	*/
	386	if (hlist_empty(&rxnet->peer_keepalive[cursor])) {
	387	if (hlist_empty(&rxnet->peer_keepalive_new)) {
	388	spin_unlock_bh(&rxnet->peer_hash_lock);
	389	goto emptied_bucket;
	390	}
	391
	392	hlist_move_list(&rxnet->peer_keepalive_new,
	393	&rxnet->peer_keepalive[cursor]);
	394	}
	395
	396	peer = hlist_entry(rxnet->peer_keepalive[cursor].first,
	397	struct rxrpc_peer, keepalive_link);
	398	hlist_del_init(&peer->keepalive_link);
	399	if (!rxrpc_get_peer_maybe(peer))
	400	goto next_peer;
	401
	402	spin_unlock_bh(&rxnet->peer_hash_lock);
	403
	404	_debug("peer %u {%pISp}", peer->debug_id, &peer->srx.transport);
	405
	406	recalc:
	407	diff = ktime_divns(ktime_sub(peer->last_tx_at, base), NSEC_PER_SEC);
	408	if (diff < -30 \|\| diff > 30)
	409	goto send; /* LSW of 64-bit time probably wrapped on 32-bit */
	410	diff += RXRPC_KEEPALIVE_TIME - 1;
	411	if (diff < 0)
	412	goto send;
	413
	414	slot = (diff > RXRPC_KEEPALIVE_TIME - 1) ? RXRPC_KEEPALIVE_TIME - 1 : diff;
415	if (slot == 0)
416	goto send;
417
418	/* A transmission to this peer occurred since last we examined it so
419	* put it into the appropriate future bucket.
420	*/
421	slot = (slot + cursor) % ARRAY_SIZE(rxnet->peer_keepalive);
422	spin_lock_bh(&rxnet->peer_hash_lock);
423	hlist_add_head(&peer->keepalive_link, &rxnet->peer_keepalive[slot]);
424	rxrpc_put_peer(peer);
425	goto next_peer;
426
427	send:
428	rxrpc_send_keepalive(peer);
429	now = ktime_get_real();
430	goto recalc;
431
432	emptied_bucket:
433	cursor++;
434	if (cursor >= ARRAY_SIZE(rxnet->peer_keepalive))
435	cursor = 0;
436	base = ktime_add_ns(base, NSEC_PER_SEC);
437	goto next_bucket;
438
439	resched:
440	rxnet->peer_keepalive_base = base;
441	rxnet->peer_keepalive_cursor = cursor;
442	delay = nsecs_to_jiffies(-diff) + 1;
443	timer_reduce(&rxnet->peer_keepalive_timer, jiffies + delay);
444	out:
445	_leave("");
446	}