linux/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 ([email protected])
 */

#define pr_fmt(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)
{ … }

/*
 * 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)
{ … }

/*
 * 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)
{ … }

/*
 * 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)
{ … }

/*
 * 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)
{ … }

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

/*
 * Initialise peer record.
 */
static void rxrpc_init_peer(struct rxrpc_local *local, struct rxrpc_peer *peer,
			    unsigned long hash_key)
{ … }

/*
 * 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)
{ … }

static void rxrpc_free_peer(struct rxrpc_peer *peer)
{ … }

/*
 * 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)
{ … }

/*
 * 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)
{ … }

/*
 * Get a ref on a peer record.
 */
struct rxrpc_peer *rxrpc_get_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why)
{ … }

/*
 * 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)
{ … }

/*
 * Discard a peer record.
 */
static void __rxrpc_put_peer(struct rxrpc_peer *peer)
{ … }

/*
 * Drop a ref on a peer record.
 */
void rxrpc_put_peer(struct rxrpc_peer *peer, enum rxrpc_peer_trace why)
{ … }

/*
 * Make sure all peer records have been discarded.
 */
void rxrpc_destroy_all_peers(struct rxrpc_net *rxnet)
{ … }

/**
 * 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)
{ … }
EXPORT_SYMBOL(…);

/**
 * 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)
{ … }
EXPORT_SYMBOL(…);

/**
 * 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)
{ … }
EXPORT_SYMBOL(…);

/**
 * 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)
{ … }
EXPORT_SYMBOL(…);