/*
   * INET		An implementation of the TCP/IP protocol suite for the LINUX
   *		operating system.  INET is implemented using the  BSD Socket
   *		interface as the means of communication with the user level.
   *
   *		This file implements the various access functions for the
   *		PROC file system.  This is very similar to the IPv4 version,
   *		except it reports the sockets in the INET6 address family.
   *

   * Authors:	David S. Miller (davem@caip.rutgers.edu)

   *		YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

   *
   *		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/socket.h>
  #include <linux/net.h>
  #include <linux/ipv6.h>
  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>
  #include <linux/stddef.h>

  #include <linux/export.h>

  #include <net/net_namespace.h>

  #include <net/ip.h>

  #include <net/sock.h>
  #include <net/tcp.h>

  #include <net/udp.h>

  #include <net/transp_v6.h>
  #include <net/ipv6.h>

  #define MAX4(a, b, c, d) \
  	max_t(u32, max_t(u32, a, b), max_t(u32, c, d))
  #define SNMP_MIB_MAX MAX4(UDP_MIB_MAX, TCP_MIB_MAX, \
  			IPSTATS_MIB_MAX, ICMP_MIB_MAX)

  static int sockstat6_seq_show(struct seq_file *seq, void *v)
  {

  	struct net *net = seq->private;

  	seq_printf(seq, "TCP6: inuse %d
  ",

  		       sock_prot_inuse_get(net, &tcpv6_prot));

  	seq_printf(seq, "UDP6: inuse %d
  ",

  		       sock_prot_inuse_get(net, &udpv6_prot));

  	seq_printf(seq, "UDPLITE6: inuse %d
  ",

  			sock_prot_inuse_get(net, &udplitev6_prot));

  	seq_printf(seq, "RAW6: inuse %d
  ",

  		       sock_prot_inuse_get(net, &rawv6_prot));

  	seq_printf(seq, "FRAG6: inuse %u memory %lu
  ",

  		   atomic_read(&net->ipv6.frags.rhashtable.nelems),
  		   frag_mem_limit(&net->ipv6.frags));

  	return 0;
  }

  static int sockstat6_seq_open(struct inode *inode, struct file *file)
  {
  	return single_open_net(inode, file, sockstat6_seq_show);
  }
  
  static const struct file_operations sockstat6_seq_fops = {
  	.owner	 = THIS_MODULE,
  	.open	 = sockstat6_seq_open,
  	.read	 = seq_read,
  	.llseek	 = seq_lseek,
  	.release = single_release_net,
  };

  static const struct snmp_mib snmp6_ipstats_list[] = {

  /* ipv6 mib according to RFC 2465 */

  	SNMP_MIB_ITEM("Ip6InReceives", IPSTATS_MIB_INPKTS),

  	SNMP_MIB_ITEM("Ip6InHdrErrors", IPSTATS_MIB_INHDRERRORS),
  	SNMP_MIB_ITEM("Ip6InTooBigErrors", IPSTATS_MIB_INTOOBIGERRORS),
  	SNMP_MIB_ITEM("Ip6InNoRoutes", IPSTATS_MIB_INNOROUTES),
  	SNMP_MIB_ITEM("Ip6InAddrErrors", IPSTATS_MIB_INADDRERRORS),
  	SNMP_MIB_ITEM("Ip6InUnknownProtos", IPSTATS_MIB_INUNKNOWNPROTOS),
  	SNMP_MIB_ITEM("Ip6InTruncatedPkts", IPSTATS_MIB_INTRUNCATEDPKTS),
  	SNMP_MIB_ITEM("Ip6InDiscards", IPSTATS_MIB_INDISCARDS),
  	SNMP_MIB_ITEM("Ip6InDelivers", IPSTATS_MIB_INDELIVERS),
  	SNMP_MIB_ITEM("Ip6OutForwDatagrams", IPSTATS_MIB_OUTFORWDATAGRAMS),

  	SNMP_MIB_ITEM("Ip6OutRequests", IPSTATS_MIB_OUTPKTS),

  	SNMP_MIB_ITEM("Ip6OutDiscards", IPSTATS_MIB_OUTDISCARDS),
  	SNMP_MIB_ITEM("Ip6OutNoRoutes", IPSTATS_MIB_OUTNOROUTES),
  	SNMP_MIB_ITEM("Ip6ReasmTimeout", IPSTATS_MIB_REASMTIMEOUT),
  	SNMP_MIB_ITEM("Ip6ReasmReqds", IPSTATS_MIB_REASMREQDS),
  	SNMP_MIB_ITEM("Ip6ReasmOKs", IPSTATS_MIB_REASMOKS),
  	SNMP_MIB_ITEM("Ip6ReasmFails", IPSTATS_MIB_REASMFAILS),
  	SNMP_MIB_ITEM("Ip6FragOKs", IPSTATS_MIB_FRAGOKS),
  	SNMP_MIB_ITEM("Ip6FragFails", IPSTATS_MIB_FRAGFAILS),
  	SNMP_MIB_ITEM("Ip6FragCreates", IPSTATS_MIB_FRAGCREATES),
  	SNMP_MIB_ITEM("Ip6InMcastPkts", IPSTATS_MIB_INMCASTPKTS),
  	SNMP_MIB_ITEM("Ip6OutMcastPkts", IPSTATS_MIB_OUTMCASTPKTS),

  	SNMP_MIB_ITEM("Ip6InOctets", IPSTATS_MIB_INOCTETS),
  	SNMP_MIB_ITEM("Ip6OutOctets", IPSTATS_MIB_OUTOCTETS),
  	SNMP_MIB_ITEM("Ip6InMcastOctets", IPSTATS_MIB_INMCASTOCTETS),
  	SNMP_MIB_ITEM("Ip6OutMcastOctets", IPSTATS_MIB_OUTMCASTOCTETS),
  	SNMP_MIB_ITEM("Ip6InBcastOctets", IPSTATS_MIB_INBCASTOCTETS),
  	SNMP_MIB_ITEM("Ip6OutBcastOctets", IPSTATS_MIB_OUTBCASTOCTETS),

  	/* IPSTATS_MIB_CSUMERRORS is not relevant in IPv6 (no checksum) */

  	SNMP_MIB_ITEM("Ip6InNoECTPkts", IPSTATS_MIB_NOECTPKTS),
  	SNMP_MIB_ITEM("Ip6InECT1Pkts", IPSTATS_MIB_ECT1PKTS),
  	SNMP_MIB_ITEM("Ip6InECT0Pkts", IPSTATS_MIB_ECT0PKTS),
  	SNMP_MIB_ITEM("Ip6InCEPkts", IPSTATS_MIB_CEPKTS),

  	SNMP_MIB_SENTINEL
  };

  static const struct snmp_mib snmp6_icmp6_list[] = {

  /* icmpv6 mib according to RFC 2466 */

  	SNMP_MIB_ITEM("Icmp6InMsgs", ICMP6_MIB_INMSGS),
  	SNMP_MIB_ITEM("Icmp6InErrors", ICMP6_MIB_INERRORS),

  	SNMP_MIB_ITEM("Icmp6OutMsgs", ICMP6_MIB_OUTMSGS),

  	SNMP_MIB_ITEM("Icmp6OutErrors", ICMP6_MIB_OUTERRORS),

  	SNMP_MIB_ITEM("Icmp6InCsumErrors", ICMP6_MIB_CSUMERRORS),

  	SNMP_MIB_SENTINEL
  };

  /* RFC 4293 v6 ICMPMsgStatsTable; named items for RFC 2466 compatibility */

  static const char *const icmp6type2name[256] = {

  	[ICMPV6_DEST_UNREACH] = "DestUnreachs",
  	[ICMPV6_PKT_TOOBIG] = "PktTooBigs",
  	[ICMPV6_TIME_EXCEED] = "TimeExcds",
  	[ICMPV6_PARAMPROB] = "ParmProblems",

  	[ICMPV6_ECHO_REQUEST] = "Echos",

  	[ICMPV6_ECHO_REPLY] = "EchoReplies",
  	[ICMPV6_MGM_QUERY] = "GroupMembQueries",
  	[ICMPV6_MGM_REPORT] = "GroupMembResponses",
  	[ICMPV6_MGM_REDUCTION] = "GroupMembReductions",
  	[ICMPV6_MLD2_REPORT] = "MLDv2Reports",
  	[NDISC_ROUTER_ADVERTISEMENT] = "RouterAdvertisements",
  	[NDISC_ROUTER_SOLICITATION] = "RouterSolicits",
  	[NDISC_NEIGHBOUR_ADVERTISEMENT] = "NeighborAdvertisements",
  	[NDISC_NEIGHBOUR_SOLICITATION] = "NeighborSolicits",

  	[NDISC_REDIRECT] = "Redirects",

  };

  static const struct snmp_mib snmp6_udp6_list[] = {

  	SNMP_MIB_ITEM("Udp6InDatagrams", UDP_MIB_INDATAGRAMS),
  	SNMP_MIB_ITEM("Udp6NoPorts", UDP_MIB_NOPORTS),
  	SNMP_MIB_ITEM("Udp6InErrors", UDP_MIB_INERRORS),
  	SNMP_MIB_ITEM("Udp6OutDatagrams", UDP_MIB_OUTDATAGRAMS),

  	SNMP_MIB_ITEM("Udp6RcvbufErrors", UDP_MIB_RCVBUFERRORS),
  	SNMP_MIB_ITEM("Udp6SndbufErrors", UDP_MIB_SNDBUFERRORS),

  	SNMP_MIB_ITEM("Udp6InCsumErrors", UDP_MIB_CSUMERRORS),

  	SNMP_MIB_ITEM("Udp6IgnoredMulti", UDP_MIB_IGNOREDMULTI),

  	SNMP_MIB_SENTINEL
  };

  static const struct snmp_mib snmp6_udplite6_list[] = {

  	SNMP_MIB_ITEM("UdpLite6InDatagrams", UDP_MIB_INDATAGRAMS),
  	SNMP_MIB_ITEM("UdpLite6NoPorts", UDP_MIB_NOPORTS),
  	SNMP_MIB_ITEM("UdpLite6InErrors", UDP_MIB_INERRORS),
  	SNMP_MIB_ITEM("UdpLite6OutDatagrams", UDP_MIB_OUTDATAGRAMS),

  	SNMP_MIB_ITEM("UdpLite6RcvbufErrors", UDP_MIB_RCVBUFERRORS),
  	SNMP_MIB_ITEM("UdpLite6SndbufErrors", UDP_MIB_SNDBUFERRORS),

  	SNMP_MIB_ITEM("UdpLite6InCsumErrors", UDP_MIB_CSUMERRORS),

  	SNMP_MIB_SENTINEL
  };

  static void snmp6_seq_show_icmpv6msg(struct seq_file *seq, atomic_long_t *smib)

  {

  	char name[32];

  	int i;
  
  	/* print by name -- deprecated items */
  	for (i = 0; i < ICMP6MSG_MIB_MAX; i++) {
  		int icmptype;

  		const char *p;

  
  		icmptype = i & 0xff;
  		p = icmp6type2name[icmptype];
  		if (!p)	/* don't print un-named types here */
  			continue;

  		snprintf(name, sizeof(name), "Icmp6%s%s",

  			i & 0x100 ? "Out" : "In", p);
  		seq_printf(seq, "%-32s\t%lu
  ", name,

  			   atomic_long_read(smib + i));

  	}
  
  	/* print by number (nonzero only) - ICMPMsgStat format */
  	for (i = 0; i < ICMP6MSG_MIB_MAX; i++) {
  		unsigned long val;

  		val = atomic_long_read(smib + i);

  		if (!val)
  			continue;

  		snprintf(name, sizeof(name), "Icmp6%sType%u",

  			i & 0x100 ?  "Out" : "In", i & 0xff);
  		seq_printf(seq, "%-32s\t%lu
  ", name, val);
  	}

  }

  /* can be called either with percpu mib (pcpumib != NULL),
   * or shared one (smib != NULL)
   */

  static void snmp6_seq_show_item(struct seq_file *seq, void __percpu *pcpumib,

  				atomic_long_t *smib,

  				const struct snmp_mib *itemlist)

  {

  	unsigned long buff[SNMP_MIB_MAX];

  	int i;

  	if (pcpumib) {
  		memset(buff, 0, sizeof(unsigned long) * SNMP_MIB_MAX);
  
  		snmp_get_cpu_field_batch(buff, itemlist, pcpumib);
  		for (i = 0; itemlist[i].name; i++)
  			seq_printf(seq, "%-32s\t%lu
  ",
  				   itemlist[i].name, buff[i]);
  	} else {
  		for (i = 0; itemlist[i].name; i++)
  			seq_printf(seq, "%-32s\t%lu
  ", itemlist[i].name,
  				   atomic_long_read(smib + itemlist[i].entry));

  	}

  }

  static void snmp6_seq_show_item64(struct seq_file *seq, void __percpu *mib,

  				  const struct snmp_mib *itemlist, size_t syncpoff)
  {

  	u64 buff64[SNMP_MIB_MAX];

  	int i;

  	memset(buff64, 0, sizeof(u64) * SNMP_MIB_MAX);

  
  	snmp_get_cpu_field64_batch(buff64, itemlist, mib, syncpoff);

  	for (i = 0; itemlist[i].name; i++)

  		seq_printf(seq, "%-32s\t%llu
  ", itemlist[i].name, buff64[i]);

  }

  static int snmp6_seq_show(struct seq_file *seq, void *v)
  {

  	struct net *net = (struct net *)seq->private;

  	snmp6_seq_show_item64(seq, net->mib.ipv6_statistics,

  			    snmp6_ipstats_list, offsetof(struct ipstats_mib, syncp));

  	snmp6_seq_show_item(seq, net->mib.icmpv6_statistics,

  			    NULL, snmp6_icmp6_list);

  	snmp6_seq_show_icmpv6msg(seq, net->mib.icmpv6msg_statistics->mibs);

  	snmp6_seq_show_item(seq, net->mib.udp_stats_in6,

  			    NULL, snmp6_udp6_list);

  	snmp6_seq_show_item(seq, net->mib.udplite_stats_in6,

  			    NULL, snmp6_udplite6_list);

  	return 0;
  }

  static int snmp6_seq_open(struct inode *inode, struct file *file)
  {

  	return single_open_net(inode, file, snmp6_seq_show);

  }

  static const struct file_operations snmp6_seq_fops = {

  	.owner	 = THIS_MODULE,
  	.open	 = snmp6_seq_open,
  	.read	 = seq_read,
  	.llseek	 = seq_lseek,

  	.release = single_release_net,

  };

  static int snmp6_dev_seq_show(struct seq_file *seq, void *v)
  {
  	struct inet6_dev *idev = (struct inet6_dev *)seq->private;
  
  	seq_printf(seq, "%-32s\t%u
  ", "ifIndex", idev->dev->ifindex);

  	snmp6_seq_show_item64(seq, idev->stats.ipv6,

  			    snmp6_ipstats_list, offsetof(struct ipstats_mib, syncp));

  	snmp6_seq_show_item(seq, NULL, idev->stats.icmpv6dev->mibs,

  			    snmp6_icmp6_list);

  	snmp6_seq_show_icmpv6msg(seq, idev->stats.icmpv6msgdev->mibs);

  	return 0;
  }
  
  static int snmp6_dev_seq_open(struct inode *inode, struct file *file)
  {

  	return single_open(file, snmp6_dev_seq_show, PDE_DATA(inode));

  }
  
  static const struct file_operations snmp6_dev_seq_fops = {
  	.owner	 = THIS_MODULE,
  	.open	 = snmp6_dev_seq_open,
  	.read	 = seq_read,
  	.llseek	 = seq_lseek,
  	.release = single_release,
  };

  int snmp6_register_dev(struct inet6_dev *idev)
  {
  	struct proc_dir_entry *p;

  	struct net *net;

  
  	if (!idev || !idev->dev)
  		return -EINVAL;

  	net = dev_net(idev->dev);

  	if (!net->mib.proc_net_devsnmp6)

  		return -ENOENT;

  	p = proc_create_data(idev->dev->name, S_IRUGO,

  			     net->mib.proc_net_devsnmp6,
  			     &snmp6_dev_seq_fops, idev);

  	if (!p)
  		return -ENOMEM;

  	idev->stats.proc_dir_entry = p;
  	return 0;
  }
  
  int snmp6_unregister_dev(struct inet6_dev *idev)
  {

  	struct net *net = dev_net(idev->dev);
  	if (!net->mib.proc_net_devsnmp6)

  		return -ENOENT;

  	if (!idev->stats.proc_dir_entry)

  		return -EINVAL;

  	proc_remove(idev->stats.proc_dir_entry);

  	idev->stats.proc_dir_entry = NULL;

  	return 0;
  }

  static int __net_init ipv6_proc_init_net(struct net *net)

  {

  	if (!proc_create("sockstat6", S_IRUGO, net->proc_net,
  			 &sockstat6_seq_fops))

  		return -ENOMEM;

  	if (!proc_create("snmp6", S_IRUGO, net->proc_net, &snmp6_seq_fops))

  		goto proc_snmp6_fail;
  
  	net->mib.proc_net_devsnmp6 = proc_mkdir("dev_snmp6", net->proc_net);
  	if (!net->mib.proc_net_devsnmp6)
  		goto proc_dev_snmp6_fail;

  	return 0;

  proc_dev_snmp6_fail:

  	remove_proc_entry("snmp6", net->proc_net);

  proc_snmp6_fail:

  	remove_proc_entry("sockstat6", net->proc_net);

  	return -ENOMEM;

  }

  static void __net_exit ipv6_proc_exit_net(struct net *net)

  {

  	remove_proc_entry("sockstat6", net->proc_net);
  	remove_proc_entry("dev_snmp6", net->proc_net);
  	remove_proc_entry("snmp6", net->proc_net);

  }
  
  static struct pernet_operations ipv6_proc_ops = {
  	.init = ipv6_proc_init_net,
  	.exit = ipv6_proc_exit_net,
  };

  int __init ipv6_misc_proc_init(void)
  {

  	return register_pernet_subsys(&ipv6_proc_ops);

  }
  
  void ipv6_misc_proc_exit(void)
  {

  	unregister_pernet_subsys(&ipv6_proc_ops);

  }