/*
   * net/tipc/config.c: TIPC configuration management code

   *

   * Copyright (c) 2002-2006, Ericsson AB

   * Copyright (c) 2004-2007, 2010-2011, Wind River Systems

   * All rights reserved.
   *

   * Redistribution and use in source and binary forms, with or without

   * modification, are permitted provided that the following conditions are met:
   *

   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 3. Neither the names of the copyright holders nor the names of its
   *    contributors may be used to endorse or promote products derived from
   *    this software without specific prior written permission.

   *

   * Alternatively, this software may be distributed under the terms of the
   * GNU General Public License ("GPL") version 2 as published by the Free
   * Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include "core.h"

  #include "port.h"

  #include "name_table.h"

  #include "config.h"

  static u32 config_port_ref;

  static DEFINE_SPINLOCK(config_lock);

  
  static const void *req_tlv_area;	/* request message TLV area */
  static int req_tlv_space;		/* request message TLV area size */
  static int rep_headroom;		/* reply message headroom to use */

  struct sk_buff *tipc_cfg_reply_alloc(int payload_size)

  {
  	struct sk_buff *buf;
  
  	buf = alloc_skb(rep_headroom + payload_size, GFP_ATOMIC);
  	if (buf)
  		skb_reserve(buf, rep_headroom);
  	return buf;
  }

  int tipc_cfg_append_tlv(struct sk_buff *buf, int tlv_type,

  			void *tlv_data, int tlv_data_size)

  {

  	struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(buf);

  	int new_tlv_space = TLV_SPACE(tlv_data_size);

  	if (skb_tailroom(buf) < new_tlv_space)

  		return 0;

  	skb_put(buf, new_tlv_space);
  	tlv->tlv_type = htons(tlv_type);
  	tlv->tlv_len  = htons(TLV_LENGTH(tlv_data_size));
  	if (tlv_data_size && tlv_data)
  		memcpy(TLV_DATA(tlv), tlv_data, tlv_data_size);
  	return 1;
  }

  static struct sk_buff *tipc_cfg_reply_unsigned_type(u16 tlv_type, u32 value)

  {
  	struct sk_buff *buf;

  	__be32 value_net;

  	buf = tipc_cfg_reply_alloc(TLV_SPACE(sizeof(value)));

  	if (buf) {
  		value_net = htonl(value);

  		tipc_cfg_append_tlv(buf, tlv_type, &value_net,

  				    sizeof(value_net));

  	}
  	return buf;
  }

  static struct sk_buff *tipc_cfg_reply_unsigned(u32 value)
  {
  	return tipc_cfg_reply_unsigned_type(TIPC_TLV_UNSIGNED, value);
  }

  struct sk_buff *tipc_cfg_reply_string_type(u16 tlv_type, char *string)

  {
  	struct sk_buff *buf;
  	int string_len = strlen(string) + 1;

  	buf = tipc_cfg_reply_alloc(TLV_SPACE(string_len));

  	if (buf)

  		tipc_cfg_append_tlv(buf, tlv_type, string, string_len);

  	return buf;
  }

  #define MAX_STATS_INFO 2000
  
  static struct sk_buff *tipc_show_stats(void)
  {
  	struct sk_buff *buf;
  	struct tlv_desc *rep_tlv;
  	struct print_buf pb;
  	int str_len;
  	u32 value;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_UNSIGNED))
  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
  
  	value = ntohl(*(u32 *)TLV_DATA(req_tlv_area));
  	if (value != 0)
  		return tipc_cfg_reply_error_string("unsupported argument");
  
  	buf = tipc_cfg_reply_alloc(TLV_SPACE(MAX_STATS_INFO));
  	if (buf == NULL)
  		return NULL;
  
  	rep_tlv = (struct tlv_desc *)buf->data;
  	tipc_printbuf_init(&pb, (char *)TLV_DATA(rep_tlv), MAX_STATS_INFO);
  
  	tipc_printf(&pb, "TIPC version " TIPC_MOD_VER "
  ");
  
  	/* Use additional tipc_printf()'s to return more info ... */
  
  	str_len = tipc_printbuf_validate(&pb);
  	skb_put(buf, TLV_SPACE(str_len));
  	TLV_SET(rep_tlv, TIPC_TLV_ULTRA_STRING, NULL, str_len);
  
  	return buf;
  }

  static struct sk_buff *cfg_enable_bearer(void)
  {
  	struct tipc_bearer_config *args;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_BEARER_CONFIG))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  
  	args = (struct tipc_bearer_config *)TLV_DATA(req_tlv_area);
  	if (tipc_enable_bearer(args->name,

  			       ntohl(args->disc_domain),

  			       ntohl(args->priority)))

  		return tipc_cfg_reply_error_string("unable to enable bearer");

  	return tipc_cfg_reply_none();

  }
  
  static struct sk_buff *cfg_disable_bearer(void)
  {
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_BEARER_NAME))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  
  	if (tipc_disable_bearer((char *)TLV_DATA(req_tlv_area)))

  		return tipc_cfg_reply_error_string("unable to disable bearer");

  	return tipc_cfg_reply_none();

  }
  
  static struct sk_buff *cfg_set_own_addr(void)
  {
  	u32 addr;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  	addr = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));

  	if (addr == tipc_own_addr)

  		return tipc_cfg_reply_none();
  	if (!tipc_addr_node_valid(addr))
  		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
  						   " (node address)");

  	if (tipc_mode == TIPC_NET_MODE)

  		return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
  						   " (cannot change node address once assigned)");

  	/*

  	 * Must release all spinlocks before calling start_net() because
  	 * Linux version of TIPC calls eth_media_start() which calls
  	 * register_netdevice_notifier() which may block!
  	 *
  	 * Temporarily releasing the lock should be harmless for non-Linux TIPC,
  	 * but Linux version of eth_media_start() should really be reworked
  	 * so that it can be called with spinlocks held.
  	 */

  
  	spin_unlock_bh(&config_lock);

  	tipc_core_start_net(addr);

  	spin_lock_bh(&config_lock);

  	return tipc_cfg_reply_none();

  }
  
  static struct sk_buff *cfg_set_remote_mng(void)
  {
  	u32 value;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_UNSIGNED))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  	value = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));

  	tipc_remote_management = (value != 0);

  	return tipc_cfg_reply_none();

  }
  
  static struct sk_buff *cfg_set_max_publications(void)
  {
  	u32 value;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_UNSIGNED))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  	value = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));

  	if (value != delimit(value, 1, 65535))

  		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
  						   " (max publications must be 1-65535)");

  	tipc_max_publications = value;

  	return tipc_cfg_reply_none();

  }
  
  static struct sk_buff *cfg_set_max_subscriptions(void)
  {
  	u32 value;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_UNSIGNED))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  	value = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));

  	if (value != delimit(value, 1, 65535))

  		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
  						   " (max subscriptions must be 1-65535");

  	tipc_max_subscriptions = value;

  	return tipc_cfg_reply_none();

  }
  
  static struct sk_buff *cfg_set_max_ports(void)
  {

  	u32 value;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_UNSIGNED))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  	value = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));

  	if (value == tipc_max_ports)
  		return tipc_cfg_reply_none();

  	if (value != delimit(value, 127, 65535))

  		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
  						   " (max ports must be 127-65535)");

  	if (tipc_mode != TIPC_NOT_RUNNING)

  		return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED

  			" (cannot change max ports while TIPC is active)");

  	tipc_max_ports = value;

  	return tipc_cfg_reply_none();

  }

  static struct sk_buff *cfg_set_netid(void)
  {
  	u32 value;
  
  	if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_UNSIGNED))

  		return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);

  	value = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));

  	if (value == tipc_net_id)
  		return tipc_cfg_reply_none();

  	if (value != delimit(value, 1, 9999))

  		return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
  						   " (network id must be 1-9999)");

  	if (tipc_mode == TIPC_NET_MODE)

  		return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED

  			" (cannot change network id once TIPC has joined a network)");
  	tipc_net_id = value;
  	return tipc_cfg_reply_none();

  }

  struct sk_buff *tipc_cfg_do_cmd(u32 orig_node, u16 cmd, const void *request_area,
  				int request_space, int reply_headroom)

  {
  	struct sk_buff *rep_tlv_buf;
  
  	spin_lock_bh(&config_lock);
  
  	/* Save request and reply details in a well-known location */
  
  	req_tlv_area = request_area;
  	req_tlv_space = request_space;
  	rep_headroom = reply_headroom;
  
  	/* Check command authorization */
  
  	if (likely(orig_node == tipc_own_addr)) {
  		/* command is permitted */
  	} else if (cmd >= 0x8000) {

  		rep_tlv_buf = tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
  							  " (cannot be done remotely)");

  		goto exit;
  	} else if (!tipc_remote_management) {

  		rep_tlv_buf = tipc_cfg_reply_error_string(TIPC_CFG_NO_REMOTE);

  		goto exit;

  	} else if (cmd >= 0x4000) {

  		u32 domain = 0;

  		if ((tipc_nametbl_translate(TIPC_ZM_SRV, 0, &domain) == 0) ||

  		    (domain != orig_node)) {

  			rep_tlv_buf = tipc_cfg_reply_error_string(TIPC_CFG_NOT_ZONE_MSTR);

  			goto exit;
  		}
  	}
  
  	/* Call appropriate processing routine */
  
  	switch (cmd) {
  	case TIPC_CMD_NOOP:

  		rep_tlv_buf = tipc_cfg_reply_none();

  		break;
  	case TIPC_CMD_GET_NODES:

  		rep_tlv_buf = tipc_node_get_nodes(req_tlv_area, req_tlv_space);

  		break;
  	case TIPC_CMD_GET_LINKS:

  		rep_tlv_buf = tipc_node_get_links(req_tlv_area, req_tlv_space);

  		break;
  	case TIPC_CMD_SHOW_LINK_STATS:

  		rep_tlv_buf = tipc_link_cmd_show_stats(req_tlv_area, req_tlv_space);

  		break;
  	case TIPC_CMD_RESET_LINK_STATS:

  		rep_tlv_buf = tipc_link_cmd_reset_stats(req_tlv_area, req_tlv_space);

  		break;
  	case TIPC_CMD_SHOW_NAME_TABLE:

  		rep_tlv_buf = tipc_nametbl_get(req_tlv_area, req_tlv_space);

  		break;
  	case TIPC_CMD_GET_BEARER_NAMES:

  		rep_tlv_buf = tipc_bearer_get_names();

  		break;
  	case TIPC_CMD_GET_MEDIA_NAMES:

  		rep_tlv_buf = tipc_media_get_names();

  		break;
  	case TIPC_CMD_SHOW_PORTS:

  		rep_tlv_buf = tipc_port_get_ports();

  		break;

  	case TIPC_CMD_SET_LOG_SIZE:

  		rep_tlv_buf = tipc_log_resize_cmd(req_tlv_area, req_tlv_space);

  		break;
  	case TIPC_CMD_DUMP_LOG:

  		rep_tlv_buf = tipc_log_dump();

  		break;

  	case TIPC_CMD_SHOW_STATS:
  		rep_tlv_buf = tipc_show_stats();
  		break;

  	case TIPC_CMD_SET_LINK_TOL:
  	case TIPC_CMD_SET_LINK_PRI:
  	case TIPC_CMD_SET_LINK_WINDOW:

  		rep_tlv_buf = tipc_link_cmd_config(req_tlv_area, req_tlv_space, cmd);

  		break;
  	case TIPC_CMD_ENABLE_BEARER:
  		rep_tlv_buf = cfg_enable_bearer();
  		break;
  	case TIPC_CMD_DISABLE_BEARER:
  		rep_tlv_buf = cfg_disable_bearer();
  		break;
  	case TIPC_CMD_SET_NODE_ADDR:
  		rep_tlv_buf = cfg_set_own_addr();
  		break;
  	case TIPC_CMD_SET_REMOTE_MNG:
  		rep_tlv_buf = cfg_set_remote_mng();
  		break;
  	case TIPC_CMD_SET_MAX_PORTS:
  		rep_tlv_buf = cfg_set_max_ports();
  		break;
  	case TIPC_CMD_SET_MAX_PUBL:
  		rep_tlv_buf = cfg_set_max_publications();
  		break;
  	case TIPC_CMD_SET_MAX_SUBSCR:
  		rep_tlv_buf = cfg_set_max_subscriptions();
  		break;

  	case TIPC_CMD_SET_NETID:
  		rep_tlv_buf = cfg_set_netid();
  		break;
  	case TIPC_CMD_GET_REMOTE_MNG:

  		rep_tlv_buf = tipc_cfg_reply_unsigned(tipc_remote_management);

  		break;
  	case TIPC_CMD_GET_MAX_PORTS:

  		rep_tlv_buf = tipc_cfg_reply_unsigned(tipc_max_ports);

  		break;
  	case TIPC_CMD_GET_MAX_PUBL:

  		rep_tlv_buf = tipc_cfg_reply_unsigned(tipc_max_publications);

  		break;
  	case TIPC_CMD_GET_MAX_SUBSCR:

  		rep_tlv_buf = tipc_cfg_reply_unsigned(tipc_max_subscriptions);

  		break;

  	case TIPC_CMD_GET_NETID:

  		rep_tlv_buf = tipc_cfg_reply_unsigned(tipc_net_id);

  		break;

  	case TIPC_CMD_NOT_NET_ADMIN:
  		rep_tlv_buf =
  			tipc_cfg_reply_error_string(TIPC_CFG_NOT_NET_ADMIN);
  		break;

  	case TIPC_CMD_SET_MAX_ZONES:
  	case TIPC_CMD_GET_MAX_ZONES:

  	case TIPC_CMD_SET_MAX_SLAVES:
  	case TIPC_CMD_GET_MAX_SLAVES:

  	case TIPC_CMD_SET_MAX_CLUSTERS:
  	case TIPC_CMD_GET_MAX_CLUSTERS:

  	case TIPC_CMD_SET_MAX_NODES:
  	case TIPC_CMD_GET_MAX_NODES:

  		rep_tlv_buf = tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
  							  " (obsolete command)");
  		break;

  	default:

  		rep_tlv_buf = tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
  							  " (unknown command)");

  		break;
  	}
  
  	/* Return reply buffer */
  exit:
  	spin_unlock_bh(&config_lock);
  	return rep_tlv_buf;
  }
  
  static void cfg_named_msg_event(void *userdata,
  				u32 port_ref,
  				struct sk_buff **buf,
  				const unchar *msg,
  				u32 size,

  				u32 importance,

  				struct tipc_portid const *orig,
  				struct tipc_name_seq const *dest)
  {
  	struct tipc_cfg_msg_hdr *req_hdr;
  	struct tipc_cfg_msg_hdr *rep_hdr;
  	struct sk_buff *rep_buf;
  
  	/* Validate configuration message header (ignore invalid message) */
  
  	req_hdr = (struct tipc_cfg_msg_hdr *)msg;
  	if ((size < sizeof(*req_hdr)) ||
  	    (size != TCM_ALIGN(ntohl(req_hdr->tcm_len))) ||
  	    (ntohs(req_hdr->tcm_flags) != TCM_F_REQUEST)) {

  		warn("Invalid configuration message discarded
  ");

  		return;
  	}
  
  	/* Generate reply for request (if can't, return request) */

  	rep_buf = tipc_cfg_do_cmd(orig->node,

  				  ntohs(req_hdr->tcm_type),

  				  msg + sizeof(*req_hdr),
  				  size - sizeof(*req_hdr),
  				  BUF_HEADROOM + MAX_H_SIZE + sizeof(*rep_hdr));

  	if (rep_buf) {
  		skb_push(rep_buf, sizeof(*rep_hdr));
  		rep_hdr = (struct tipc_cfg_msg_hdr *)rep_buf->data;
  		memcpy(rep_hdr, req_hdr, sizeof(*rep_hdr));
  		rep_hdr->tcm_len = htonl(rep_buf->len);
  		rep_hdr->tcm_flags &= htons(~TCM_F_REQUEST);
  	} else {
  		rep_buf = *buf;
  		*buf = NULL;
  	}
  
  	/* NEED TO ADD CODE TO HANDLE FAILED SEND (SUCH AS CONGESTION) */
  	tipc_send_buf2port(port_ref, orig, rep_buf, rep_buf->len);
  }

  int tipc_cfg_init(void)

  {
  	struct tipc_name_seq seq;
  	int res;

  	res = tipc_createport(NULL, TIPC_CRITICAL_IMPORTANCE,

  			      NULL, NULL, NULL,
  			      NULL, cfg_named_msg_event, NULL,

  			      NULL, &config_port_ref);

  	if (res)
  		goto failed;
  
  	seq.type = TIPC_CFG_SRV;
  	seq.lower = seq.upper = tipc_own_addr;

  	res = tipc_nametbl_publish_rsv(config_port_ref, TIPC_ZONE_SCOPE, &seq);

  	if (res)
  		goto failed;
  
  	return 0;
  
  failed:
  	err("Unable to create configuration service
  ");

  	return res;
  }

  void tipc_cfg_stop(void)

  {

  	if (config_port_ref) {
  		tipc_deleteport(config_port_ref);
  		config_port_ref = 0;

  	}
  }