// SPDX-License-Identifier: GPL-2.0-or-later

  /* /proc/net/ support for AF_RXRPC
   *
   * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
   * Written by David Howells (dhowells@redhat.com)

   */
  
  #include <linux/module.h>
  #include <net/sock.h>
  #include <net/af_rxrpc.h>
  #include "ar-internal.h"

  static const char *const rxrpc_conn_states[RXRPC_CONN__NR_STATES] = {
  	[RXRPC_CONN_UNUSED]			= "Unused  ",
  	[RXRPC_CONN_CLIENT]			= "Client  ",

  	[RXRPC_CONN_SERVICE_PREALLOC]		= "SvPrealc",

  	[RXRPC_CONN_SERVICE_UNSECURED]		= "SvUnsec ",
  	[RXRPC_CONN_SERVICE_CHALLENGING]	= "SvChall ",
  	[RXRPC_CONN_SERVICE]			= "SvSecure",
  	[RXRPC_CONN_REMOTELY_ABORTED]		= "RmtAbort",
  	[RXRPC_CONN_LOCALLY_ABORTED]		= "LocAbort",

  };

  /*
   * generate a list of extant and dead calls in /proc/net/rxrpc_calls
   */
  static void *rxrpc_call_seq_start(struct seq_file *seq, loff_t *_pos)

  	__acquires(rcu)
  	__acquires(rxnet->call_lock)

  {

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));

  	rcu_read_lock();

  	read_lock(&rxnet->call_lock);
  	return seq_list_start_head(&rxnet->calls, *_pos);

  }
  
  static void *rxrpc_call_seq_next(struct seq_file *seq, void *v, loff_t *pos)
  {

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  
  	return seq_list_next(v, &rxnet->calls, pos);

  }
  
  static void rxrpc_call_seq_stop(struct seq_file *seq, void *v)

  	__releases(rxnet->call_lock)
  	__releases(rcu)

  {

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  
  	read_unlock(&rxnet->call_lock);

  	rcu_read_unlock();

  }
  
  static int rxrpc_call_seq_show(struct seq_file *seq, void *v)
  {

  	struct rxrpc_local *local;
  	struct rxrpc_sock *rx;
  	struct rxrpc_peer *peer;

  	struct rxrpc_call *call;

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));

  	unsigned long timeout = 0;

  	rxrpc_seq_t tx_hard_ack, rx_hard_ack;

  	char lbuff[50], rbuff[50];

  	if (v == &rxnet->calls) {

  		seq_puts(seq,

  			 "Proto Local                                          "
  			 " Remote                                         "

  			 " SvID ConnID   CallID   End Use State    Abort   "

  			 " UserID           TxSeq    TW RxSeq    RW RxSerial RxTimo
  ");

  		return 0;
  	}
  
  	call = list_entry(v, struct rxrpc_call, link);

  	rx = rcu_dereference(call->socket);

  	if (rx) {
  		local = READ_ONCE(rx->local);
  		if (local)

  			sprintf(lbuff, "%pISpc", &local->srx.transport);

  		else
  			strcpy(lbuff, "no_local");
  	} else {
  		strcpy(lbuff, "no_socket");
  	}

  	peer = call->peer;
  	if (peer)

  		sprintf(rbuff, "%pISpc", &peer->srx.transport);

  	else
  		strcpy(rbuff, "no_connection");

  	if (call->state != RXRPC_CALL_SERVER_PREALLOC) {
  		timeout = READ_ONCE(call->expect_rx_by);

  		timeout -= jiffies;
  	}

  	tx_hard_ack = READ_ONCE(call->tx_hard_ack);
  	rx_hard_ack = READ_ONCE(call->rx_hard_ack);

  	seq_printf(seq,

  		   "UDP   %-47.47s %-47.47s %4x %08x %08x %s %3u"

  		   " %-8.8s %08x %lx %08x %02x %08x %02x %08x %06lx
  ",

  		   lbuff,
  		   rbuff,

  		   call->service_id,

  		   call->cid,
  		   call->call_id,

  		   rxrpc_is_service_call(call) ? "Svc" : "Clt",

  		   atomic_read(&call->usage),
  		   rxrpc_call_states[call->state],

  		   call->abort_code,

  		   call->user_call_ID,
  		   tx_hard_ack, READ_ONCE(call->tx_top) - tx_hard_ack,

  		   rx_hard_ack, READ_ONCE(call->rx_top) - rx_hard_ack,

  		   call->rx_serial,

  		   timeout);

  
  	return 0;
  }

  const struct seq_operations rxrpc_call_seq_ops = {

  	.start  = rxrpc_call_seq_start,
  	.next   = rxrpc_call_seq_next,
  	.stop   = rxrpc_call_seq_stop,
  	.show   = rxrpc_call_seq_show,
  };

  /*
   * generate a list of extant virtual connections in /proc/net/rxrpc_conns
   */
  static void *rxrpc_connection_seq_start(struct seq_file *seq, loff_t *_pos)

  	__acquires(rxnet->conn_lock)

  {

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  
  	read_lock(&rxnet->conn_lock);
  	return seq_list_start_head(&rxnet->conn_proc_list, *_pos);

  }
  
  static void *rxrpc_connection_seq_next(struct seq_file *seq, void *v,
  				       loff_t *pos)
  {

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  
  	return seq_list_next(v, &rxnet->conn_proc_list, pos);

  }
  
  static void rxrpc_connection_seq_stop(struct seq_file *seq, void *v)

  	__releases(rxnet->conn_lock)

  {

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  
  	read_unlock(&rxnet->conn_lock);

  }
  
  static int rxrpc_connection_seq_show(struct seq_file *seq, void *v)
  {
  	struct rxrpc_connection *conn;

  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));

  	char lbuff[50], rbuff[50];

  	if (v == &rxnet->conn_proc_list) {

  		seq_puts(seq,

  			 "Proto Local                                          "
  			 " Remote                                         "

  			 " SvID ConnID   End Use State    Key     "

  			 " Serial   ISerial
  "
  			 );
  		return 0;
  	}

  	conn = list_entry(v, struct rxrpc_connection, proc_link);

  	if (conn->state == RXRPC_CONN_SERVICE_PREALLOC) {
  		strcpy(lbuff, "no_local");
  		strcpy(rbuff, "no_connection");
  		goto print;
  	}

  	sprintf(lbuff, "%pISpc", &conn->params.local->srx.transport);

  	sprintf(rbuff, "%pISpc", &conn->params.peer->srx.transport);

  print:

  	seq_printf(seq,

  		   "UDP   %-47.47s %-47.47s %4x %08x %s %3u"

  		   " %s %08x %08x %08x %08x %08x %08x %08x
  ",

  		   lbuff,
  		   rbuff,

  		   conn->service_id,

  		   conn->proto.cid,

  		   rxrpc_conn_is_service(conn) ? "Svc" : "Clt",

  		   atomic_read(&conn->usage),
  		   rxrpc_conn_states[conn->state],

  		   key_serial(conn->params.key),

  		   atomic_read(&conn->serial),

  		   conn->hi_serial,
  		   conn->channels[0].call_id,
  		   conn->channels[1].call_id,
  		   conn->channels[2].call_id,
  		   conn->channels[3].call_id);

  
  	return 0;
  }

  const struct seq_operations rxrpc_connection_seq_ops = {

  	.start  = rxrpc_connection_seq_start,
  	.next   = rxrpc_connection_seq_next,
  	.stop   = rxrpc_connection_seq_stop,
  	.show   = rxrpc_connection_seq_show,
  };

  
  /*
   * generate a list of extant virtual peers in /proc/net/rxrpc/peers
   */
  static int rxrpc_peer_seq_show(struct seq_file *seq, void *v)
  {
  	struct rxrpc_peer *peer;
  	time64_t now;
  	char lbuff[50], rbuff[50];
  
  	if (v == SEQ_START_TOKEN) {
  		seq_puts(seq,
  			 "Proto Local                                          "
  			 " Remote                                         "
  			 " Use CW  MTU   LastUse          RTT Rc
  "
  			 );
  		return 0;
  	}
  
  	peer = list_entry(v, struct rxrpc_peer, hash_link);
  
  	sprintf(lbuff, "%pISpc", &peer->local->srx.transport);
  
  	sprintf(rbuff, "%pISpc", &peer->srx.transport);
  
  	now = ktime_get_seconds();
  	seq_printf(seq,
  		   "UDP   %-47.47s %-47.47s %3u"
  		   " %3u %5u %6llus %12llu %2u
  ",
  		   lbuff,
  		   rbuff,
  		   atomic_read(&peer->usage),
  		   peer->cong_cwnd,
  		   peer->mtu,
  		   now - peer->last_tx_at,
  		   peer->rtt,
  		   peer->rtt_cursor);
  
  	return 0;
  }
  
  static void *rxrpc_peer_seq_start(struct seq_file *seq, loff_t *_pos)
  	__acquires(rcu)
  {
  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  	unsigned int bucket, n;
  	unsigned int shift = 32 - HASH_BITS(rxnet->peer_hash);
  	void *p;
  
  	rcu_read_lock();
  
  	if (*_pos >= UINT_MAX)
  		return NULL;
  
  	n = *_pos & ((1U << shift) - 1);
  	bucket = *_pos >> shift;
  	for (;;) {
  		if (bucket >= HASH_SIZE(rxnet->peer_hash)) {
  			*_pos = UINT_MAX;
  			return NULL;
  		}
  		if (n == 0) {
  			if (bucket == 0)
  				return SEQ_START_TOKEN;
  			*_pos += 1;
  			n++;
  		}
  
  		p = seq_hlist_start_rcu(&rxnet->peer_hash[bucket], n - 1);
  		if (p)
  			return p;
  		bucket++;
  		n = 1;
  		*_pos = (bucket << shift) | n;
  	}
  }
  
  static void *rxrpc_peer_seq_next(struct seq_file *seq, void *v, loff_t *_pos)
  {
  	struct rxrpc_net *rxnet = rxrpc_net(seq_file_net(seq));
  	unsigned int bucket, n;
  	unsigned int shift = 32 - HASH_BITS(rxnet->peer_hash);
  	void *p;
  
  	if (*_pos >= UINT_MAX)
  		return NULL;
  
  	bucket = *_pos >> shift;
  
  	p = seq_hlist_next_rcu(v, &rxnet->peer_hash[bucket], _pos);
  	if (p)
  		return p;
  
  	for (;;) {
  		bucket++;
  		n = 1;
  		*_pos = (bucket << shift) | n;
  
  		if (bucket >= HASH_SIZE(rxnet->peer_hash)) {
  			*_pos = UINT_MAX;
  			return NULL;
  		}
  		if (n == 0) {
  			*_pos += 1;
  			n++;
  		}
  
  		p = seq_hlist_start_rcu(&rxnet->peer_hash[bucket], n - 1);
  		if (p)
  			return p;
  	}
  }
  
  static void rxrpc_peer_seq_stop(struct seq_file *seq, void *v)
  	__releases(rcu)
  {
  	rcu_read_unlock();
  }
  
  
  const struct seq_operations rxrpc_peer_seq_ops = {
  	.start  = rxrpc_peer_seq_start,
  	.next   = rxrpc_peer_seq_next,
  	.stop   = rxrpc_peer_seq_stop,
  	.show   = rxrpc_peer_seq_show,
  };