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

// SPDX-License-Identifier: GPL-2.0-or-later
/* RxRPC remote transport endpoint record management
 *
 * Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/net.h>
#include <linux/skbuff.h>
#include <linux/udp.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/slab.h>
#include <linux/hashtable.h>
#include <net/sock.h>
#include <net/af_rxrpc.h>
#include <net/ip.h>
#include <net/route.h>
#include <net/ip6_route.h>
#include "ar-internal.h"

static const struct sockaddr_rxrpc rxrpc_null_addr;

/*
 * Hash a peer key.
 */
static unsigned long rxrpc_peer_hash_key(struct rxrpc_local *local,
					 const struct sockaddr_rxrpc *srx)
{
	const u16 *p;
	unsigned int i, size;
	unsigned long hash_key;

	_enter("");

	hash_key = (unsigned long)local / __alignof__(*local);
	hash_key += srx->transport_type;
	hash_key += srx->transport_len;
	hash_key += srx->transport.family;

	switch (srx->transport.family) {
	case AF_INET:
		hash_key += (u16 __force)srx->transport.sin.sin_port;
		size = sizeof(srx->transport.sin.sin_addr);
		p = (u16 *)&srx->transport.sin.sin_addr;
		break;
#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		hash_key += (u16 __force)srx->transport.sin.sin_port;
		size = sizeof(srx->transport.sin6.sin6_addr);
		p = (u16 *)&srx->transport.sin6.sin6_addr;
		break;
#endif
	default:
		WARN(1, "AF_RXRPC: Unsupported transport address family\n");
		return 0;
	}

	/* Step through the peer address in 16-bit portions for speed */
	for (i = 0; i < size; i += sizeof(*p), p++)
		hash_key += *p;

	_leave(" 0x%lx", hash_key);
	return hash_key;
}

/*
 * Compare a peer to a key.  Return -ve, 0 or +ve to indicate less than, same
 * or greater than.
 *
 * Unfortunately, the primitives in linux/hashtable.h don't allow for sorted
 * buckets and mid-bucket insertion, so we don't make full use of this
 * information at this point.
 */
static long rxrpc_peer_cmp_key(const struct rxrpc_peer *peer,
			       struct rxrpc_local *local,
			       const struct sockaddr_rxrpc *srx,
			       unsigned long hash_key)
{
	long diff;

	diff = ((peer->hash_key - hash_key) ?:
		((unsigned long)peer->local - (unsigned long)local) ?:
		(peer->srx.transport_type - srx->transport_type) ?:
		(peer->srx.transport_len - srx->transport_len) ?:
		(peer->srx.transport.family - srx->transport.family));
	if (diff != 0)
		return diff;

	switch (srx->transport.family) {
	case AF_INET:
		return ((u16 __force)peer->srx.transport.sin.sin_port -
			(u16 __force)srx->transport.sin.sin_port) ?:
			memcmp(&peer->srx.transport.sin.sin_addr,
			       &srx->transport.sin.sin_addr,
			       sizeof(struct in_addr));
#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		return ((u16 __force)peer->srx.transport.sin6.sin6_port -
			(u16 __force)srx->transport.sin6.sin6_port) ?:
			memcmp(&peer->srx.transport.sin6.sin6_addr,
			       &srx->transport.sin6.sin6_addr,
			       sizeof(struct in6_addr));
#endif
	default:
		BUG();
	}
}

/*
 * Look up a remote transport endpoint for the specified address using RCU.
 */
static struct rxrpc_peer *__rxrpc_lookup_peer_rcu(
	struct rxrpc_local *local,
	const struct sockaddr_rxrpc *srx,
	unsigned long hash_key)
{
	struct rxrpc_peer *peer;
	struct rxrpc_net *rxnet = local->rxnet;

	hash_for_each_possible_rcu(rxnet->peer_hash, peer, hash_link, hash_key) {
		if (rxrpc_peer_cmp_key(peer, local, srx, hash_key) == 0 &&
		    refcount_read(&peer->ref) > 0)
			return peer;
	}

	return NULL;
}

/*
 * Look up a remote transport endpoint for the specified address using RCU.
 */
struct rxrpc_peer *rxrpc_lookup_peer_rcu(struct rxrpc_local *local,
					 const struct sockaddr_rxrpc *srx)
{
	struct rxrpc_peer *peer;
	unsigned long hash_key = rxrpc_peer_hash_key(local, srx);

	peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
	if (peer)
		_leave(" = %p {u=%d}", peer, refcount_read(&peer->ref));
	return peer;
}

/*
 * assess the MTU size for the network interface through which this peer is
 * reached
 */
static void rxrpc_assess_MTU_size(struct rxrpc_local *local,
				  struct rxrpc_peer *peer)
{
	struct net *net = local->net;
	struct dst_entry *dst;
	struct rtable *rt;
	struct flowi fl;
	struct flowi4 *fl4 = &fl.u.ip4;
#ifdef CONFIG_AF_RXRPC_IPV6
	struct flowi6 *fl6 = &fl.u.ip6;
#endif

	peer->if_mtu = 1500;

	memset(&fl, 0, sizeof(fl));
	switch (peer->srx.transport.family) {
	case AF_INET:
		rt = ip_route_output_ports(
			net, fl4, NULL,
			peer->srx.transport.sin.sin_addr.s_addr, 0,
			htons(7000), htons(7001), IPPROTO_UDP, 0, 0);
		if (IS_ERR(rt)) {
			_leave(" [route err %ld]", PTR_ERR(rt));
			return;
		}
		dst = &rt->dst;
		break;

#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		fl6->flowi6_iif = LOOPBACK_IFINDEX;
		fl6->flowi6_scope = RT_SCOPE_UNIVERSE;
		fl6->flowi6_proto = IPPROTO_UDP;
		memcpy(&fl6->daddr, &peer->srx.transport.sin6.sin6_addr,
		       sizeof(struct in6_addr));
		fl6->fl6_dport = htons(7001);
		fl6->fl6_sport = htons(7000);
		dst = ip6_route_output(net, NULL, fl6);
		if (dst->error) {
			_leave(" [route err %d]", dst->error);
			return;
		}
		break;
#endif

	default:
		BUG();
	}

	peer->if_mtu = dst_mtu(dst);
	dst_release(dst);

	_leave(" [if_mtu %u]", peer->if_mtu);
}

/*
 * Allocate a peer.
 */
struct rxrpc_peer *rxrpc_alloc_peer(struct rxrpc_local *local, gfp_t gfp,
				    enum rxrpc_peer_trace why)
{
	struct rxrpc_peer *peer;

	_enter("");

	peer = kzalloc(sizeof(struct rxrpc_peer), gfp);
	if (peer) {
		refcount_set(&peer->ref, 1);
		peer->local = rxrpc_get_local(local, rxrpc_local_get_peer);
		INIT_HLIST_HEAD(&peer->error_targets);
		peer->service_conns = RB_ROOT;
		seqlock_init(&peer->service_conn_lock);
		spin_lock_init(&peer->lock);
		spin_lock_init(&peer->rtt_input_lock);
		peer->debug_id = atomic_inc_return(&rxrpc_debug_id);

		rxrpc_peer_init_rtt(peer);

		peer->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
		trace_rxrpc_peer(peer->debug_id, 1, why);
	}

	_leave(" = %p", peer);
	return peer;
}

/*
 * Initialise peer record.
 */
static void rxrpc_init_peer(struct rxrpc_local *local, struct rxrpc_peer *peer,
			    unsigned long hash_key)
{
	peer->hash_key = hash_key;
	rxrpc_assess_MTU_size(local, peer);
	peer->mtu = peer->if_mtu;
	peer->rtt_last_req = ktime_get_real();

	switch (peer->srx.transport.family) {
	case AF_INET:
		peer->hdrsize = sizeof(struct iphdr);
		break;
#ifdef CONFIG_AF_RXRPC_IPV6
	case AF_INET6:
		peer->hdrsize = sizeof(struct ipv6hdr);
		break;
#endif
	default:
		BUG();
	}

	switch (peer->srx.transport_type) {
	case SOCK_DGRAM:
		peer->hdrsize += sizeof(struct udphdr);
		break;
	default:
		BUG();
	}

	peer->hdrsize += sizeof(struct rxrpc_wire_header);
	peer->maxdata = peer->mtu - peer->hdrsize;
}

/*
 * Set up a new peer.
 */
static struct rxrpc_peer *rxrpc_create_peer(struct rxrpc_local *local,
					    struct sockaddr_rxrpc *srx,
					    unsigned long hash_key,
					    gfp_t gfp)
{
	struct rxrpc_peer *peer;

	_enter("");

	peer = rxrpc_alloc_peer(local, gfp, rxrpc_peer_new_client);
	if (peer) {
		memcpy(&peer->srx, srx, sizeof(*srx));
		rxrpc_init_peer(local, peer, hash_key);
	}

	_leave(" = %p", peer);
	return peer;
}

static void rxrpc_free_peer(struct rxrpc_peer *peer)
{
	trace_rxrpc_peer(peer->debug_id, 0, rxrpc_peer_free);
	rxrpc_put_local(peer->local, rxrpc_local_put_peer);
	kfree_rcu(peer, rcu);
}

/*
 * Set up a new incoming peer.  There shouldn't be any other matching peers
 * since we've already done a search in the list from the non-reentrant context
 * (the data_ready handler) that is the only place we can add new peers.
 */
void rxrpc_new_incoming_peer(struct rxrpc_local *local, struct rxrpc_peer *peer)
{
	struct rxrpc_net *rxnet = local->rxnet;
	unsigned long hash_key;

	hash_key = rxrpc_peer_hash_key(local, &peer->srx);
	rxrpc_init_peer(local, peer, hash_key);

	spin_lock(&rxnet->peer_hash_lock);
	hash_add_rcu(rxnet->peer_hash, &peer->hash_link, hash_key);
	list_add_tail(&peer->keepalive_link, &rxnet->peer_keepalive_new);
	spin_unlock(&rxnet->peer_hash_lock);
}

/*
 * obtain a remote transport endpoint for the specified address
 */
struct rxrpc_peer *rxrpc_lookup_peer(struct rxrpc_local *local,
				     struct sockaddr_rxrpc *srx, gfp_t gfp)
{
	struct rxrpc_peer *peer, *candidate;
	struct rxrpc_net *rxnet = local->rxnet;
	unsigned long hash_key = rxrpc_peer_hash_key(local, srx);

	_enter("{%pISp}", &srx->transport);

	/* search the peer list first */
	rcu_read_lock();
	peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
	if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client))
		peer = NULL;
	rcu_read_unlock();

	if (!peer) {
		/* The peer is not yet present in hash - create a candidate
		 * for a new record and then redo the search.
		 */
		candidate = rxrpc_create_peer(local, srx, hash_key, gfp);
		if (!candidate) {
			_leave(" = NULL [nomem]");
			return NULL;
		}

		spin_lock(&rxnet->peer_hash_lock);

		/* Need to check that we aren't racing with someone else */
		peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
		if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client))
			peer = NULL;
		if (!peer) {
			hash_add_rcu(rxnet->peer_hash,
				     &candidate->hash_link, hash_key);
			list_add_tail(&candidate->keepalive_link,
				      &rxnet->peer_keepalive_new);
		}

		spin_unlock(&rxnet->peer_hash_lock);

		if (peer)
			rxrpc_free_peer(candidate);
		else
			peer = candidate;
	}

	_leave(" = %p {u=%d}", peer, refcount_read(&peer->ref));
	return peer;
}

/*
 * Get a ref on a peer record.
 */
struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why)
{
	int r;

	__refcount_inc(&peer->ref, &r);
	trace_rxrpc_peer(peer->debug_id, r + 1, why);
	return peer;
}

/*
 * Get a ref on a peer record unless its usage has already reached 0.
 */
struct rxrpc_peer *rxrpc_get_peer_maybe(struct rxrpc_peer *peer,
					enum rxrpc_peer_trace why)
{
	int r;

	if (peer) {
		if (__refcount_inc_not_zero(&peer->ref, &r))
			trace_rxrpc_peer(peer->debug_id, r + 1, why);
		else
			peer = NULL;
	}
	return peer;
}

/*
 * Discard a peer record.
 */
static void __rxrpc_put_peer(struct rxrpc_peer *peer)
{
	struct rxrpc_net *rxnet = peer->local->rxnet;

	ASSERT(hlist_empty(&peer->error_targets));

	spin_lock(&rxnet->peer_hash_lock);
	hash_del_rcu(&peer->hash_link);
	list_del_init(&peer->keepalive_link);
	spin_unlock(&rxnet->peer_hash_lock);

	rxrpc_free_peer(peer);
}

/*
 * Drop a ref on a peer record.
 */
void rxrpc_put_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why)
{
	unsigned int debug_id;
	bool dead;
	int r;

	if (peer) {
		debug_id = peer->debug_id;
		dead = __refcount_dec_and_test(&peer->ref, &r);
		trace_rxrpc_peer(debug_id, r - 1, why);
		if (dead)
			__rxrpc_put_peer(peer);
	}
}

/*
 * Make sure all peer records have been discarded.
 */
void rxrpc_destroy_all_peers(struct rxrpc_net *rxnet)
{
	struct rxrpc_peer *peer;
	int i;

	for (i = 0; i < HASH_SIZE(rxnet->peer_hash); i++) {
		if (hlist_empty(&rxnet->peer_hash[i]))
			continue;

		hlist_for_each_entry(peer, &rxnet->peer_hash[i], hash_link) {
			pr_err("Leaked peer %u {%u} %pISp\n",
			       peer->debug_id,
			       refcount_read(&peer->ref),
			       &peer->srx.transport);
		}
	}
}

/**
 * rxrpc_kernel_get_call_peer - Get the peer address of a call
 * @sock: The socket on which the call is in progress.
 * @call: The call to query
 *
 * Get a record for the remote peer in a call.
 */
struct rxrpc_peer *rxrpc_kernel_get_call_peer(struct socket *sock, struct rxrpc_call *call)
{
	return call->peer;
}
EXPORT_SYMBOL(rxrpc_kernel_get_call_peer);

/**
 * rxrpc_kernel_get_srtt - Get a call's peer smoothed RTT
 * @peer: The peer to query
 *
 * Get the call's peer smoothed RTT in uS or UINT_MAX if we have no samples.
 */
unsigned int rxrpc_kernel_get_srtt(const struct rxrpc_peer *peer)
{
	return peer->rtt_count > 0 ? peer->srtt_us >> 3 : UINT_MAX;
}
EXPORT_SYMBOL(rxrpc_kernel_get_srtt);

/**
 * rxrpc_kernel_remote_srx - Get the address of a peer
 * @peer: The peer to query
 *
 * Get a pointer to the address from a peer record.  The caller is responsible
 * for making sure that the address is not deallocated.
 */
const struct sockaddr_rxrpc *rxrpc_kernel_remote_srx(const struct rxrpc_peer *peer)
{
	return peer ? &peer->srx : &rxrpc_null_addr;
}
EXPORT_SYMBOL(rxrpc_kernel_remote_srx);

/**
 * rxrpc_kernel_remote_addr - Get the peer transport address of a call
 * @peer: The peer to query
 *
 * Get a pointer to the transport address from a peer record.  The caller is
 * responsible for making sure that the address is not deallocated.
 */
const struct sockaddr *rxrpc_kernel_remote_addr(const struct rxrpc_peer *peer)
{
	return (const struct sockaddr *)
		(peer ? &peer->srx.transport : &rxrpc_null_addr.transport);
}
EXPORT_SYMBOL(rxrpc_kernel_remote_addr);
Commit	Line	Data
2874c5fd	1	// SPDX-License-Identifier: GPL-2.0-or-later
be6e6707	2	/* RxRPC remote transport endpoint record management
17926a79	3	*
be6e6707	4	* Copyright (C) 2007, 2016 Red Hat, Inc. All Rights Reserved.
17926a79	5	* Written by David Howells (dhowells@redhat.com)
17926a79 DH	6	*/
17926a79 DH	7
9b6d5398 JP	8	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9b6d5398 JP	9
17926a79 DH	10	#include <linux/module.h>
	11	#include <linux/net.h>
	12	#include <linux/skbuff.h>
	13	#include <linux/udp.h>
	14	#include <linux/in.h>
75b54cb5	15	#include <linux/in6.h>
5a0e3ad6	16	#include <linux/slab.h>
be6e6707	17	#include <linux/hashtable.h>
17926a79 DH	18	#include <net/sock.h>
	19	#include <net/af_rxrpc.h>
	20	#include <net/ip.h>
224711df	21	#include <net/route.h>
75b54cb5	22	#include <net/ip6_route.h>
17926a79 DH	23	#include "ar-internal.h"
17926a79 DH	24
72904d7b DH	25	static const struct sockaddr_rxrpc rxrpc_null_addr;
72904d7b DH	26
be6e6707 DH	27	/*
	28	* Hash a peer key.
	29	*/
	30	static unsigned long rxrpc_peer_hash_key(struct rxrpc_local *local,
	31	const struct sockaddr_rxrpc *srx)
	32	{
	33	const u16 *p;
	34	unsigned int i, size;
	35	unsigned long hash_key;
	36
	37	_enter("");
	38
	39	hash_key = (unsigned long)local / __alignof__(*local);
	40	hash_key += srx->transport_type;
	41	hash_key += srx->transport_len;
	42	hash_key += srx->transport.family;
	43
	44	switch (srx->transport.family) {
	45	case AF_INET:
	46	hash_key += (u16 __force)srx->transport.sin.sin_port;
	47	size = sizeof(srx->transport.sin.sin_addr);
	48	p = (u16 *)&srx->transport.sin.sin_addr;
	49	break;
d1912747	50	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	51	case AF_INET6:
	52	hash_key += (u16 __force)srx->transport.sin.sin_port;
	53	size = sizeof(srx->transport.sin6.sin6_addr);
	54	p = (u16 *)&srx->transport.sin6.sin6_addr;
	55	break;
d1912747	56	#endif
2f9f9f52 AB	57	default:
	58	WARN(1, "AF_RXRPC: Unsupported transport address family\n");
	59	return 0;
be6e6707 DH	60	}
	61
	62	/* Step through the peer address in 16-bit portions for speed */
	63	for (i = 0; i < size; i += sizeof(*p), p++)
	64	hash_key += *p;
	65
	66	_leave(" 0x%lx", hash_key);
	67	return hash_key;
	68	}
	69
	70	/*
	71	* Compare a peer to a key. Return -ve, 0 or +ve to indicate less than, same
	72	* or greater than.
	73	*
	74	* Unfortunately, the primitives in linux/hashtable.h don't allow for sorted
	75	* buckets and mid-bucket insertion, so we don't make full use of this
	76	* information at this point.
	77	*/
	78	static long rxrpc_peer_cmp_key(const struct rxrpc_peer *peer,
	79	struct rxrpc_local *local,
	80	const struct sockaddr_rxrpc *srx,
	81	unsigned long hash_key)
	82	{
	83	long diff;
	84
	85	diff = ((peer->hash_key - hash_key) ?:
	86	((unsigned long)peer->local - (unsigned long)local) ?:
	87	(peer->srx.transport_type - srx->transport_type) ?:
	88	(peer->srx.transport_len - srx->transport_len) ?:
	89	(peer->srx.transport.family - srx->transport.family));
	90	if (diff != 0)
	91	return diff;
	92
	93	switch (srx->transport.family) {
	94	case AF_INET:
	95	return ((u16 __force)peer->srx.transport.sin.sin_port -
	96	(u16 __force)srx->transport.sin.sin_port) ?:
	97	memcmp(&peer->srx.transport.sin.sin_addr,
	98	&srx->transport.sin.sin_addr,
	99	sizeof(struct in_addr));
d1912747	100	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	101	case AF_INET6:
	102	return ((u16 __force)peer->srx.transport.sin6.sin6_port -
	103	(u16 __force)srx->transport.sin6.sin6_port) ?:
	104	memcmp(&peer->srx.transport.sin6.sin6_addr,
	105	&srx->transport.sin6.sin6_addr,
	106	sizeof(struct in6_addr));
d1912747	107	#endif
be6e6707 DH	108	default:
	109	BUG();
	110	}
	111	}
	112
	113	/*
	114	* Look up a remote transport endpoint for the specified address using RCU.
	115	*/
	116	static struct rxrpc_peer *__rxrpc_lookup_peer_rcu(
	117	struct rxrpc_local *local,
	118	const struct sockaddr_rxrpc *srx,
	119	unsigned long hash_key)
	120	{
	121	struct rxrpc_peer *peer;
2baec2c3	122	struct rxrpc_net *rxnet = local->rxnet;
be6e6707	123
2baec2c3	124	hash_for_each_possible_rcu(rxnet->peer_hash, peer, hash_link, hash_key) {
0099dc58	125	if (rxrpc_peer_cmp_key(peer, local, srx, hash_key) == 0 &&
a0575429	126	refcount_read(&peer->ref) > 0)
be6e6707	127	return peer;
be6e6707 DH	128	}
	129
	130	return NULL;
	131	}
	132
	133	/*
	134	* Look up a remote transport endpoint for the specified address using RCU.
	135	*/
	136	struct rxrpc_peer rxrpc_lookup_peer_rcu(struct rxrpc_local local,
	137	const struct sockaddr_rxrpc *srx)
	138	{
	139	struct rxrpc_peer *peer;
	140	unsigned long hash_key = rxrpc_peer_hash_key(local, srx);
	141
	142	peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
e969c92c	143	if (peer)
a0575429	144	_leave(" = %p {u=%d}", peer, refcount_read(&peer->ref));
be6e6707 DH	145	return peer;
be6e6707 DH	146	}
17926a79	147
224711df DH	148	/*
	149	* assess the MTU size for the network interface through which this peer is
	150	* reached
	151	*/
8a758d98	152	static void rxrpc_assess_MTU_size(struct rxrpc_local *local,
5e33a23b	153	struct rxrpc_peer *peer)
224711df	154	{
8a758d98	155	struct net *net = local->net;
75b54cb5	156	struct dst_entry *dst;
224711df	157	struct rtable *rt;
75b54cb5 DH	158	struct flowi fl;
75b54cb5 DH	159	struct flowi4 *fl4 = &fl.u.ip4;
d1912747	160	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5	161	struct flowi6 *fl6 = &fl.u.ip6;
d1912747	162	#endif
224711df DH	163
	164	peer->if_mtu = 1500;
	165
75b54cb5 DH	166	memset(&fl, 0, sizeof(fl));
	167	switch (peer->srx.transport.family) {
	168	case AF_INET:
	169	rt = ip_route_output_ports(
5e33a23b	170	net, fl4, NULL,
75b54cb5 DH	171	peer->srx.transport.sin.sin_addr.s_addr, 0,
	172	htons(7000), htons(7001), IPPROTO_UDP, 0, 0);
	173	if (IS_ERR(rt)) {
	174	_leave(" [route err %ld]", PTR_ERR(rt));
	175	return;
	176	}
	177	dst = &rt->dst;
	178	break;
	179
d1912747	180	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	181	case AF_INET6:
	182	fl6->flowi6_iif = LOOPBACK_IFINDEX;
	183	fl6->flowi6_scope = RT_SCOPE_UNIVERSE;
	184	fl6->flowi6_proto = IPPROTO_UDP;
	185	memcpy(&fl6->daddr, &peer->srx.transport.sin6.sin6_addr,
	186	sizeof(struct in6_addr));
	187	fl6->fl6_dport = htons(7001);
	188	fl6->fl6_sport = htons(7000);
5e33a23b	189	dst = ip6_route_output(net, NULL, fl6);
07096f61 DH	190	if (dst->error) {
07096f61 DH	191	_leave(" [route err %d]", dst->error);
75b54cb5 DH	192	return;
	193	}
	194	break;
d1912747	195	#endif
75b54cb5 DH	196
	197	default:
	198	BUG();
224711df DH	199	}
224711df DH	200
75b54cb5 DH	201	peer->if_mtu = dst_mtu(dst);
75b54cb5 DH	202	dst_release(dst);
224711df	203
a6a62b69	204	_leave(" [if_mtu %u]", peer->if_mtu);
224711df DH	205	}
224711df DH	206
17926a79	207	/*
be6e6707	208	* Allocate a peer.
17926a79	209	*/
47c810a7 DH	210	struct rxrpc_peer rxrpc_alloc_peer(struct rxrpc_local local, gfp_t gfp,
47c810a7 DH	211	enum rxrpc_peer_trace why)
17926a79 DH	212	{
	213	struct rxrpc_peer *peer;
	214
	215	_enter("");
	216
	217	peer = kzalloc(sizeof(struct rxrpc_peer), gfp);
	218	if (peer) {
a0575429	219	refcount_set(&peer->ref, 1);
0fde882f	220	peer->local = rxrpc_get_local(local, rxrpc_local_get_peer);
f66d7490	221	INIT_HLIST_HEAD(&peer->error_targets);
aa390bbe	222	peer->service_conns = RB_ROOT;
8496af50	223	seqlock_init(&peer->service_conn_lock);
17926a79	224	spin_lock_init(&peer->lock);
c1e15b49	225	spin_lock_init(&peer->rtt_input_lock);
17926a79	226	peer->debug_id = atomic_inc_return(&rxrpc_debug_id);
f7aec129	227
c410bf01 DH	228	rxrpc_peer_init_rtt(peer);
c410bf01 DH	229
1fc4fa2a	230	peer->cong_ssthresh = RXRPC_TX_MAX_WINDOW;
c838f1a7	231	trace_rxrpc_peer(peer->debug_id, 1, why);
be6e6707 DH	232	}
	233
	234	_leave(" = %p", peer);
	235	return peer;
	236	}
	237
248f219c DH	238	/*
	239	* Initialise peer record.
	240	*/
8a758d98	241	static void rxrpc_init_peer(struct rxrpc_local local, struct rxrpc_peer peer,
5e33a23b	242	unsigned long hash_key)
248f219c	243	{
08a39685	244	peer->hash_key = hash_key;
8a758d98	245	rxrpc_assess_MTU_size(local, peer);
248f219c	246	peer->mtu = peer->if_mtu;
0d4b103c	247	peer->rtt_last_req = ktime_get_real();
248f219c	248
75b54cb5 DH	249	switch (peer->srx.transport.family) {
75b54cb5 DH	250	case AF_INET:
248f219c	251	peer->hdrsize = sizeof(struct iphdr);
75b54cb5	252	break;
d1912747	253	#ifdef CONFIG_AF_RXRPC_IPV6
75b54cb5 DH	254	case AF_INET6:
	255	peer->hdrsize = sizeof(struct ipv6hdr);
	256	break;
d1912747	257	#endif
75b54cb5 DH	258	default:
	259	BUG();
	260	}
	261
	262	switch (peer->srx.transport_type) {
	263	case SOCK_DGRAM:
	264	peer->hdrsize += sizeof(struct udphdr);
	265	break;
	266	default:
248f219c DH	267	BUG();
	268	}
	269
	270	peer->hdrsize += sizeof(struct rxrpc_wire_header);
	271	peer->maxdata = peer->mtu - peer->hdrsize;
	272	}
	273
be6e6707 DH	274	/*
	275	* Set up a new peer.
	276	*/
8a758d98	277	static struct rxrpc_peer rxrpc_create_peer(struct rxrpc_local local,
be6e6707 DH	278	struct sockaddr_rxrpc *srx,
	279	unsigned long hash_key,
	280	gfp_t gfp)
	281	{
	282	struct rxrpc_peer *peer;
	283
	284	_enter("");
	285
47c810a7	286	peer = rxrpc_alloc_peer(local, gfp, rxrpc_peer_new_client);
be6e6707	287	if (peer) {
17926a79	288	memcpy(&peer->srx, srx, sizeof(*srx));
8a758d98	289	rxrpc_init_peer(local, peer, hash_key);
248f219c	290	}
17926a79	291
248f219c DH	292	_leave(" = %p", peer);
	293	return peer;
	294	}
17926a79	295
beacff50 ET	296	static void rxrpc_free_peer(struct rxrpc_peer *peer)
beacff50 ET	297	{
47c810a7	298	trace_rxrpc_peer(peer->debug_id, 0, rxrpc_peer_free);
0fde882f	299	rxrpc_put_local(peer->local, rxrpc_local_put_peer);
beacff50 ET	300	kfree_rcu(peer, rcu);
	301	}
	302
248f219c	303	/*
0099dc58 DH	304	* Set up a new incoming peer. There shouldn't be any other matching peers
	305	* since we've already done a search in the list from the non-reentrant context
	306	* (the data_ready handler) that is the only place we can add new peers.
248f219c	307	*/
8a758d98	308	void rxrpc_new_incoming_peer(struct rxrpc_local local, struct rxrpc_peer peer)
248f219c	309	{
2baec2c3	310	struct rxrpc_net *rxnet = local->rxnet;
248f219c DH	311	unsigned long hash_key;
248f219c DH	312
0099dc58	313	hash_key = rxrpc_peer_hash_key(local, &peer->srx);
8a758d98	314	rxrpc_init_peer(local, peer, hash_key);
248f219c	315
2baec2c3	316	spin_lock(&rxnet->peer_hash_lock);
0099dc58 DH	317	hash_add_rcu(rxnet->peer_hash, &peer->hash_link, hash_key);
0099dc58 DH	318	list_add_tail(&peer->keepalive_link, &rxnet->peer_keepalive_new);
2baec2c3	319	spin_unlock(&rxnet->peer_hash_lock);
17926a79 DH	320	}
	321
	322	/*
	323	* obtain a remote transport endpoint for the specified address
	324	*/
8a758d98	325	struct rxrpc_peer rxrpc_lookup_peer(struct rxrpc_local local,
be6e6707	326	struct sockaddr_rxrpc *srx, gfp_t gfp)
17926a79 DH	327	{
17926a79 DH	328	struct rxrpc_peer peer, candidate;
2baec2c3	329	struct rxrpc_net *rxnet = local->rxnet;
be6e6707	330	unsigned long hash_key = rxrpc_peer_hash_key(local, srx);
17926a79	331
75b54cb5	332	_enter("{%pISp}", &srx->transport);
17926a79 DH	333
17926a79 DH	334	/* search the peer list first */
be6e6707 DH	335	rcu_read_lock();
be6e6707 DH	336	peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
47c810a7	337	if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client))
be6e6707 DH	338	peer = NULL;
	339	rcu_read_unlock();
	340
	341	if (!peer) {
	342	/* The peer is not yet present in hash - create a candidate
	343	* for a new record and then redo the search.
	344	*/
8a758d98	345	candidate = rxrpc_create_peer(local, srx, hash_key, gfp);
be6e6707 DH	346	if (!candidate) {
	347	_leave(" = NULL [nomem]");
	348	return NULL;
	349	}
17926a79	350
3dd9c8b5	351	spin_lock(&rxnet->peer_hash_lock);
17926a79	352
be6e6707 DH	353	/* Need to check that we aren't racing with someone else */
be6e6707 DH	354	peer = __rxrpc_lookup_peer_rcu(local, srx, hash_key);
47c810a7	355	if (peer && !rxrpc_get_peer_maybe(peer, rxrpc_peer_get_lookup_client))
be6e6707	356	peer = NULL;
ace45bec	357	if (!peer) {
2baec2c3	358	hash_add_rcu(rxnet->peer_hash,
be6e6707	359	&candidate->hash_link, hash_key);
330bdcfa DH	360	list_add_tail(&candidate->keepalive_link,
330bdcfa DH	361	&rxnet->peer_keepalive_new);
ace45bec	362	}
17926a79	363
3dd9c8b5	364	spin_unlock(&rxnet->peer_hash_lock);
17926a79	365
be6e6707	366	if (peer)
beacff50	367	rxrpc_free_peer(candidate);
be6e6707 DH	368	else
	369	peer = candidate;
	370	}
17926a79	371
a0575429	372	_leave(" = %p {u=%d}", peer, refcount_read(&peer->ref));
17926a79	373	return peer;
17926a79 DH	374	}
	375
	376	/*
1159d4b4	377	* Get a ref on a peer record.
17926a79	378	*/
47c810a7	379	struct rxrpc_peer rxrpc_get_peer(struct rxrpc_peer peer, enum rxrpc_peer_trace why)
1159d4b4	380	{
a0575429	381	int r;
1159d4b4	382
a0575429	383	__refcount_inc(&peer->ref, &r);
c838f1a7	384	trace_rxrpc_peer(peer->debug_id, r + 1, why);
1159d4b4 DH	385	return peer;
	386	}
	387
	388	/*
	389	* Get a ref on a peer record unless its usage has already reached 0.
	390	*/
47c810a7 DH	391	struct rxrpc_peer rxrpc_get_peer_maybe(struct rxrpc_peer peer,
47c810a7 DH	392	enum rxrpc_peer_trace why)
1159d4b4	393	{
a0575429	394	int r;
1159d4b4 DH	395
1159d4b4 DH	396	if (peer) {
a0575429	397	if (__refcount_inc_not_zero(&peer->ref, &r))
47c810a7	398	trace_rxrpc_peer(peer->debug_id, r + 1, why);
1159d4b4 DH	399	else
	400	peer = NULL;
	401	}
	402	return peer;
	403	}
	404
1159d4b4 DH	405	/*
	406	* Discard a peer record.
	407	*/
	408	static void __rxrpc_put_peer(struct rxrpc_peer *peer)
17926a79	409	{
2baec2c3 DH	410	struct rxrpc_net *rxnet = peer->local->rxnet;
2baec2c3 DH	411
f66d7490	412	ASSERT(hlist_empty(&peer->error_targets));
17926a79	413
3dd9c8b5	414	spin_lock(&rxnet->peer_hash_lock);
be6e6707	415	hash_del_rcu(&peer->hash_link);
330bdcfa	416	list_del_init(&peer->keepalive_link);
3dd9c8b5	417	spin_unlock(&rxnet->peer_hash_lock);
17926a79	418
beacff50	419	rxrpc_free_peer(peer);
17926a79	420	}
8324f0bc	421
1159d4b4 DH	422	/*
	423	* Drop a ref on a peer record.
	424	*/
47c810a7	425	void rxrpc_put_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why)
1159d4b4	426	{
55f6c98e	427	unsigned int debug_id;
a0575429 DH	428	bool dead;
a0575429 DH	429	int r;
1159d4b4 DH	430
1159d4b4 DH	431	if (peer) {
55f6c98e	432	debug_id = peer->debug_id;
a0575429	433	dead = __refcount_dec_and_test(&peer->ref, &r);
47c810a7	434	trace_rxrpc_peer(debug_id, r - 1, why);
a0575429	435	if (dead)
1159d4b4 DH	436	__rxrpc_put_peer(peer);
	437	}
	438	}
	439
17226f12 DH	440	/*
	441	* Make sure all peer records have been discarded.
	442	*/
	443	void rxrpc_destroy_all_peers(struct rxrpc_net *rxnet)
	444	{
	445	struct rxrpc_peer *peer;
	446	int i;
	447
	448	for (i = 0; i < HASH_SIZE(rxnet->peer_hash); i++) {
	449	if (hlist_empty(&rxnet->peer_hash[i]))
	450	continue;
	451
	452	hlist_for_each_entry(peer, &rxnet->peer_hash[i], hash_link) {
	453	pr_err("Leaked peer %u {%u} %pISp\n",
	454	peer->debug_id,
a0575429	455	refcount_read(&peer->ref),
17226f12 DH	456	&peer->srx.transport);
	457	}
	458	}
	459	}
	460
8324f0bc	461	/**
72904d7b	462	* rxrpc_kernel_get_call_peer - Get the peer address of a call
8324f0bc DH	463	* @sock: The socket on which the call is in progress.
8324f0bc DH	464	* @call: The call to query
8324f0bc	465	*
72904d7b	466	* Get a record for the remote peer in a call.
8324f0bc	467	*/
72904d7b	468	struct rxrpc_peer rxrpc_kernel_get_call_peer(struct socket sock, struct rxrpc_call *call)
8324f0bc	469	{
72904d7b	470	return call->peer;
8324f0bc	471	}
72904d7b	472	EXPORT_SYMBOL(rxrpc_kernel_get_call_peer);
f4d15fb6 DH	473
f4d15fb6 DH	474	/**
c410bf01	475	* rxrpc_kernel_get_srtt - Get a call's peer smoothed RTT
72904d7b	476	* @peer: The peer to query
f4d15fb6	477	*
72904d7b	478	* Get the call's peer smoothed RTT in uS or UINT_MAX if we have no samples.
f4d15fb6	479	*/
72904d7b	480	unsigned int rxrpc_kernel_get_srtt(const struct rxrpc_peer *peer)
f4d15fb6	481	{
72904d7b DH	482	return peer->rtt_count > 0 ? peer->srtt_us >> 3 : UINT_MAX;
	483	}
	484	EXPORT_SYMBOL(rxrpc_kernel_get_srtt);
1d4adfaf	485
72904d7b DH	486	/**
	487	* rxrpc_kernel_remote_srx - Get the address of a peer
	488	* @peer: The peer to query
	489	*
	490	* Get a pointer to the address from a peer record. The caller is responsible
	491	* for making sure that the address is not deallocated.
	492	*/
	493	const struct sockaddr_rxrpc rxrpc_kernel_remote_srx(const struct rxrpc_peer peer)
	494	{
	495	return peer ? &peer->srx : &rxrpc_null_addr;
	496	}
	497	EXPORT_SYMBOL(rxrpc_kernel_remote_srx);
1d4adfaf	498
72904d7b DH	499	/**
	500	* rxrpc_kernel_remote_addr - Get the peer transport address of a call
	501	* @peer: The peer to query
	502	*
	503	* Get a pointer to the transport address from a peer record. The caller is
	504	* responsible for making sure that the address is not deallocated.
	505	*/
	506	const struct sockaddr rxrpc_kernel_remote_addr(const struct rxrpc_peer peer)
	507	{
	508	return (const struct sockaddr *)
	509	(peer ? &peer->srx.transport : &rxrpc_null_addr.transport);
f4d15fb6	510	}
72904d7b	511	EXPORT_SYMBOL(rxrpc_kernel_remote_addr);