/*
 * 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.  It is mainly used for debugging and
 *              statistics.
 *
 * Version:     $Id: proc.c,v 1.45 2001/05/16 16:45:35 davem Exp $
 *
 * Authors:     Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *              Gerald J. Heim, <heim@peanuts.informatik.uni-tuebingen.de>
 *              Fred Baumgarten, <dc6iq@insu1.etec.uni-karlsruhe.de>
 *              Erik Schoenfelder, <schoenfr@ibr.cs.tu-bs.de>
 *
 * Fixes:
 *              Alan Cox        :       UDP sockets show the rxqueue/txqueue
 *                                      using hint flag for the netinfo.
 *      Pauline Middelink       :       identd support
 *              Alan Cox        :       Make /proc safer.
 *      Erik Schoenfelder       :       /proc/net/snmp
 *              Alan Cox        :       Handle dead sockets properly.
 *      Gerhard Koerting        :       Show both timers
 *              Alan Cox        :       Allow inode to be NULL (kernel socket)
 *      Andi Kleen              :       Add support for open_requests and
 *                                      split functions for more readibility.
 *      Andi Kleen              :       Add support for /proc/net/netstat
 *      Arnaldo C. Melo         :       Convert to seq_file
 *
 *              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/types.h>
#include <net/icmp.h>
#include <net/protocol.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <net/sock.h>
#include <net/raw.h>

static int fold_prot_inuse(struct proto *proto)
{
        int res = 0;
        int cpu;

        for (cpu = 0; cpu < NR_CPUS; cpu++)
                res += proto->stats[cpu].inuse;

        return res;
}

/*
 *      Report socket allocation statistics [mea@utu.fi]
 */
static int sockstat_seq_show(struct seq_file *seq, void *v)
{
        /* From net/socket.c */
        extern void socket_seq_show(struct seq_file *seq);

        socket_seq_show(seq);
        seq_printf(seq, "TCP: inuse %d orphan %d tw %d alloc %d mem %d\n",
                   fold_prot_inuse(&tcp_prot), atomic_read(&tcp_orphan_count),
                   tcp_tw_count, atomic_read(&tcp_sockets_allocated),
                   atomic_read(&tcp_memory_allocated));
        seq_printf(seq, "UDP: inuse %d\n", fold_prot_inuse(&udp_prot));
        seq_printf(seq, "RAW: inuse %d\n", fold_prot_inuse(&raw_prot));
        seq_printf(seq,  "FRAG: inuse %d memory %d\n", ip_frag_nqueues,
                   atomic_read(&ip_frag_mem));
        return 0;
}

static int sockstat_seq_open(struct inode *inode, struct file *file)
{
        return single_open(file, sockstat_seq_show, NULL);
}

static struct file_operations sockstat_seq_fops = {
        .owner   = THIS_MODULE,
        .open    = sockstat_seq_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = single_release,
};

static unsigned long
fold_field(void *mib[], int nr)
{
        unsigned long res = 0;
        int i;

        for (i = 0; i < NR_CPUS; i++) {
                if (!cpu_possible(i))
                        continue;
                res +=
                    *((unsigned long *) (((void *) per_cpu_ptr(mib[0], i)) +
                                         sizeof (unsigned long) * nr));
                res +=
                    *((unsigned long *) (((void *) per_cpu_ptr(mib[1], i)) +
                                         sizeof (unsigned long) * nr));
        }
        return res;
}

/*
 *      Called from the PROCfs module. This outputs /proc/net/snmp.
 */
static int snmp_seq_show(struct seq_file *seq, void *v)
{
        int i;

        seq_printf(seq, "Ip: Forwarding DefaultTTL InReceives InHdrErrors "
                        "InAddrErrors ForwDatagrams InUnknownProtos "
                        "InDiscards InDelivers OutRequests OutDiscards "
                        "OutNoRoutes ReasmTimeout ReasmReqds ReasmOKs "
                        "ReasmFails FragOKs FragFails FragCreates\nIp: %d %d",
                        ipv4_devconf.forwarding ? 1 : 2, sysctl_ip_default_ttl);

        for (i = 0;
             i < offsetof(struct ip_mib, __pad) / sizeof(unsigned long); i++)
                seq_printf(seq, " %lu",
                           fold_field((void **) ip_statistics, i));

        seq_printf(seq, "\nIcmp: InMsgs InErrors InDestUnreachs InTimeExcds "
                        "InParmProbs InSrcQuenchs InRedirects InEchos "
                        "InEchoReps InTimestamps InTimestampReps InAddrMasks "
                        "InAddrMaskReps OutMsgs OutErrors OutDestUnreachs "
                        "OutTimeExcds OutParmProbs OutSrcQuenchs OutRedirects "
                        "OutEchos OutEchoReps OutTimestamps OutTimestampReps "
                        "OutAddrMasks OutAddrMaskReps\nIcmp:");

        for (i = 0;
             i < offsetof(struct icmp_mib, dummy) / sizeof(unsigned long); i++)
                seq_printf(seq, " %lu",
                           fold_field((void **) icmp_statistics, i)); 

        seq_printf(seq, "\nTcp: RtoAlgorithm RtoMin RtoMax MaxConn ActiveOpens "
                        "PassiveOpens AttemptFails EstabResets CurrEstab "
                        "InSegs OutSegs RetransSegs InErrs OutRsts\nTcp:");

        for (i = 0;
             i < offsetof(struct tcp_mib, __pad) / sizeof(unsigned long); i++) {
                if (i == (offsetof(struct tcp_mib, TcpMaxConn) / sizeof(unsigned long)))
                        /* MaxConn field is negative, RFC 2012 */
                        seq_printf(seq, " %ld", 
                                   fold_field((void **) tcp_statistics, i));
                else
                        seq_printf(seq, " %lu", 
                                   fold_field((void **) tcp_statistics, i));
        }

        seq_printf(seq, "\nUdp: InDatagrams NoPorts InErrors OutDatagrams\n"
                        "Udp:");

        for (i = 0;
             i < offsetof(struct udp_mib, __pad) / sizeof(unsigned long); i++)
                seq_printf(seq, " %lu", 
                                fold_field((void **) udp_statistics, i));

        seq_putc(seq, '\n');
        return 0;
}

static int snmp_seq_open(struct inode *inode, struct file *file)
{
        return single_open(file, snmp_seq_show, NULL);
}

static struct file_operations snmp_seq_fops = {
        .owner   = THIS_MODULE,
        .open    = snmp_seq_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = single_release,
};

/*
 *      Output /proc/net/netstat
 */
static int netstat_seq_show(struct seq_file *seq, void *v)
{
        int i;

        seq_puts(seq, "TcpExt: SyncookiesSent SyncookiesRecv SyncookiesFailed"
                      " EmbryonicRsts PruneCalled RcvPruned OfoPruned"
                      " OutOfWindowIcmps LockDroppedIcmps ArpFilter"
                      " TW TWRecycled TWKilled"
                      " PAWSPassive PAWSActive PAWSEstab"
                      " DelayedACKs DelayedACKLocked DelayedACKLost"
                      " ListenOverflows ListenDrops"
                      " TCPPrequeued TCPDirectCopyFromBacklog"
                      " TCPDirectCopyFromPrequeue TCPPrequeueDropped"
                      " TCPHPHits TCPHPHitsToUser"
                      " TCPPureAcks TCPHPAcks"
                      " TCPRenoRecovery TCPSackRecovery"
                      " TCPSACKReneging"
                      " TCPFACKReorder TCPSACKReorder TCPRenoReorder"
                      " TCPTSReorder"
                      " TCPFullUndo TCPPartialUndo TCPDSACKUndo TCPLossUndo"
                      " TCPLoss TCPLostRetransmit"
                      " TCPRenoFailures TCPSackFailures TCPLossFailures"
                      " TCPFastRetrans TCPForwardRetrans TCPSlowStartRetrans"
                      " TCPTimeouts"
                      " TCPRenoRecoveryFail TCPSackRecoveryFail"
                      " TCPSchedulerFailed TCPRcvCollapsed"
                      " TCPDSACKOldSent TCPDSACKOfoSent TCPDSACKRecv"
                      " TCPDSACKOfoRecv"
                      " TCPAbortOnSyn TCPAbortOnData TCPAbortOnClose"
                      " TCPAbortOnMemory TCPAbortOnTimeout TCPAbortOnLinger"
                      " TCPAbortFailed TCPMemoryPressures\n"
                      "TcpExt:");
        for (i = 0;
             i < offsetof(struct linux_mib, __pad) / sizeof(unsigned long); 
             i++)
                seq_printf(seq, " %lu", 
                           fold_field((void **) net_statistics, i)); 
        seq_putc(seq, '\n');
        return 0;
}

static int netstat_seq_open(struct inode *inode, struct file *file)
{
        return single_open(file, netstat_seq_show, NULL);
}

static struct file_operations netstat_seq_fops = {
        .owner   = THIS_MODULE,
        .open    = netstat_seq_open,
        .read    = seq_read,
        .llseek  = seq_lseek,
        .release = single_release,
};

int __init ip_misc_proc_init(void)
{
        int rc = 0;

        if (!proc_net_fops_create("netstat", S_IRUGO, &netstat_seq_fops))
                goto out_netstat;

        if (!proc_net_fops_create("snmp", S_IRUGO, &snmp_seq_fops))
                goto out_snmp;

        if (!proc_net_fops_create("sockstat", S_IRUGO, &sockstat_seq_fops))
                goto out_sockstat;
out:
        return rc;
out_sockstat:
        proc_net_remove("snmp");
out_snmp:
        proc_net_remove("netstat");
out_netstat:
        rc = -ENOMEM;
        goto out;
}