/*
 *  Linux kernel interface
 *
 */

#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-features.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>

#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <sys/types.h>
#ifdef HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#include <errno.h>
#include <stddef.h>

#include "kernel_linux.h"

struct ip_mib   cached_ip_mib;
struct ip6_mib   cached_ip6_mib;
struct icmp_mib cached_icmp_mib;
struct icmp6_mib cached_icmp6_mib;
struct icmp4_msg_mib cached_icmp4_msg_mib;
struct tcp_mib  cached_tcp_mib;
struct udp_mib  cached_udp_mib;
struct udp6_mib  cached_udp6_mib;

struct stats_descr {
    const char *prefix;
    const char *col_name;
    void *var;
    unsigned int offset;
    unsigned int validity_offset;
};

static const struct stats_descr ipv4_snmp_stats[] = {
    { "Ip:", "Forwarding", &cached_ip_mib,
      offsetof(struct ip_mib, ipForwarding) },
    { "Ip:", "DefaultTTL", &cached_ip_mib,
      offsetof(struct ip_mib, ipDefaultTTL) },
    { "Ip:", "InReceives", &cached_ip_mib,
      offsetof(struct ip_mib, ipInReceives) },
    { "Ip:", "InHdrErrors", &cached_ip_mib,
      offsetof(struct ip_mib, ipInHdrErrors) },
    { "Ip:", "InAddrErrors", &cached_ip_mib,
      offsetof(struct ip_mib, ipInAddrErrors) },
    { "Ip:", "ForwDatagrams", &cached_ip_mib,
      offsetof(struct ip_mib, ipForwDatagrams) },
    { "Ip:", "InUnknownProtos", &cached_ip_mib,
      offsetof(struct ip_mib, ipInUnknownProtos) },
    { "Ip:", "InDiscards", &cached_ip_mib,
      offsetof(struct ip_mib, ipInDiscards) },
    { "Ip:", "InDelivers", &cached_ip_mib,
      offsetof(struct ip_mib, ipInDelivers) },
    { "Ip:", "OutRequests", &cached_ip_mib,
      offsetof(struct ip_mib, ipOutRequests) },
    { "Ip:", "OutDiscards", &cached_ip_mib,
      offsetof(struct ip_mib, ipOutDiscards) },
    { "Ip:", "OutNoRoutes", &cached_ip_mib,
      offsetof(struct ip_mib, ipOutNoRoutes) },
    { "Ip:", "ReasmTimeout", &cached_ip_mib,
      offsetof(struct ip_mib, ipReasmTimeout) },
    { "Ip:", "ReasmReqds", &cached_ip_mib,
      offsetof(struct ip_mib, ipReasmReqds) },
    { "Ip:", "ReasmOKs", &cached_ip_mib,
      offsetof(struct ip_mib, ipReasmOKs) },
    { "Ip:", "ReasmFails", &cached_ip_mib,
      offsetof(struct ip_mib, ipReasmFails) },
    { "Ip:", "FragOKs", &cached_ip_mib,
      offsetof(struct ip_mib, ipFragOKs) },
    { "Ip:", "FragFails", &cached_ip_mib,
      offsetof(struct ip_mib, ipFragFails) },
    { "Ip:", "FragCreates", &cached_ip_mib,
      offsetof(struct ip_mib, ipFragCreates) },

    { "Icmp:", "InMsgs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInMsgs) },
    { "Icmp:", "InErrors", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInErrors) },
    { "Icmp:", "InDestUnreachs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInDestUnreachs) },
    { "Icmp:", "InTimeExcds", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInTimeExcds) },
    { "Icmp:", "InParmProbs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInParmProbs) },
    { "Icmp:", "InSrcQuenchs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInSrcQuenchs) },
    { "Icmp:", "InRedirects", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInRedirects) },
    { "Icmp:", "InEchos", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInEchos) },
    { "Icmp:", "InEchoReps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInEchoReps) },
    { "Icmp:", "InTimestamps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInTimestamps) },
    { "Icmp:", "InTimestampReps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInTimestampReps) },
    { "Icmp:", "InAddrMasks", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInAddrMasks) },
    { "Icmp:", "InAddrMaskReps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpInAddrMaskReps) },
    { "Icmp:", "OutMsgs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutMsgs) },
    { "Icmp:", "OutErrors", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutErrors) },
    { "Icmp:", "OutDestUnreachs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutDestUnreachs) },
    { "Icmp:", "OutTimeExcds", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutTimeExcds) },
    { "Icmp:", "OutParmProbs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutParmProbs) },
    { "Icmp:", "OutSrcQuenchs", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutSrcQuenchs) },
    { "Icmp:", "OutRedirects", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutRedirects) },
    { "Icmp:", "OutEchos", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutEchos) },
    { "Icmp:", "OutEchoReps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutEchoReps) },
    { "Icmp:", "OutTimestamps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutTimestamps) },
    { "Icmp:", "OutTimestampReps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutTimestampReps) },
    { "Icmp:", "OutAddrMasks", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutAddrMasks) },
    { "Icmp:", "OutAddrMaskReps", &cached_icmp_mib,
      offsetof(struct icmp_mib, icmpOutAddrMaskReps) },

    { "Tcp:", "RtoAlgorithm", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpRtoAlgorithm) },
    { "Tcp:", "RtoMin", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpRtoMin) },
    { "Tcp:", "RtoMax", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpRtoMax) },
    { "Tcp:", "MaxConn", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpMaxConn) },
    { "Tcp:", "ActiveOpens", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpActiveOpens) },
    { "Tcp:", "PassiveOpens", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpPassiveOpens) },
    { "Tcp:", "AttemptFails", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpAttemptFails) },
    { "Tcp:", "EstabResets", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpEstabResets) },
    { "Tcp:", "CurrEstab", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpCurrEstab) },
    { "Tcp:", "InSegs", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpInSegs) },
    { "Tcp:", "OutSegs", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpOutSegs) },
    { "Tcp:", "RetransSegs", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpRetransSegs) },
    { "Tcp:", "InErrs", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpInErrs),
      offsetof(struct tcp_mib, tcpInErrsValid) },
    { "Tcp:", "OutRsts", &cached_tcp_mib,
      offsetof(struct tcp_mib, tcpOutRsts),
      offsetof(struct tcp_mib, tcpOutRstsValid) },

    { "Udp:", "InDatagrams", &cached_udp_mib,
      offsetof(struct udp_mib, udpInDatagrams) },
    { "Udp:", "NoPorts", &cached_udp_mib,
      offsetof(struct udp_mib, udpNoPorts) },
    { "Udp:", "InErrors", &cached_udp_mib,
      offsetof(struct udp_mib, udpInErrors) },
    { "Udp:", "OutDatagrams", &cached_udp_mib,
      offsetof(struct udp_mib, udpOutDatagrams) },
};

#define IP6_STATS_LINE   "Ip6"
#define ICMP6_STATS_LINE "Icmp6"
#define UDP6_STATS_LINE "Udp6"

#define IP6_STATS_PREFIX_LEN	3
#define ICMP6_STATS_PREFIX_LEN	5
#define UDP6_STATS_PREFIX_LEN   4

netsnmp_feature_child_of(linux_ip6_stat_all, libnetsnmpmibs);

netsnmp_feature_child_of(linux_read_ip6_stat, linux_ip6_stat_all);

static int
decode_icmp_msg(char *line, char *data, struct icmp4_msg_mib *msg)
{
    char *token, *saveptr, *lineptr, *saveptr1, *dataptr, *delim = NULL;
    char line_cpy[1024];
    char data_cpy[1024];
    long index;

    if(data == NULL)
        return -1;

    /*
     * Since we are using strtok, there is a possiblity of the orginal data
     * getting modified. So we take a local copy for this purpose even though
     * its expensive.
     */
    strlcpy(line_cpy, line, sizeof(line_cpy));
    strlcpy(data_cpy, data, sizeof(data_cpy));

    lineptr = line_cpy;
    dataptr = data_cpy;
    saveptr1 = saveptr = NULL;
    while (1) {
        if(NULL == (token = strtok_r(lineptr, " ", &saveptr)))
            break;
        lineptr = NULL;
        errno = 0;
        if (0 == strncmp(strsep(&token, "e"), "OutTyp", 6)) {
            index = strtol(token, &delim, 0);
            if (ERANGE == errno) {
                continue;
            } else if (index > 255) {
                continue;
            } else if (index < 0) {
                continue;
            }
            if (NULL == (token = strtok_r(dataptr, " ", &saveptr1)))
                break;
            dataptr = NULL;
            msg->vals[index].OutType = atoi(token);
        } else {
            index = strtol(token, &delim, 0);
            if (ERANGE == errno) {
                continue;
            } else if (index > 255) {
                continue;
            } else if (index < 0) {
                continue;
            }
            if(NULL == (token = strtok_r(dataptr, " ", &saveptr1)))
                break;
            dataptr = NULL;
            msg->vals[index].InType = atoi(token);
        }
    }
    return 0;
}

static int
linux_read_mibII_stats(void)
{
    FILE           *in;
    char            line[1024], data[1024], *linepos, *datapos, *pfx, *hdr, *v;
    const struct stats_descr *d;
    const struct stats_descr *const end = ipv4_snmp_stats +
                          sizeof(ipv4_snmp_stats) / sizeof(ipv4_snmp_stats[0]);
    int             ret = 0;

    in = fopen("/proc/net/snmp", "r");
    if (!in) {
        DEBUGMSGTL(("mibII/kernel_linux","Unable to open /proc/net/snmp"));
        return -1;
    }

    while (fgets(line, sizeof(line), in) && fgets(data, sizeof(data), in)) {
        if (!(pfx = strtok_r(line, " ", &linepos)))
            continue;
        if (!strtok_r(data, " ", &datapos))
            continue;
        if (strcmp(pfx, "IcmpMsg:") == 0) {
            decode_icmp_msg(linepos, datapos, &cached_icmp4_msg_mib);
        } else {
            while ((hdr = strtok_r(linepos, " \n", &linepos)) &&
                   (v = strtok_r(datapos, " \n", &datapos))) {
                for (d = ipv4_snmp_stats; d < end; d++) {
                    if (strcmp(d->prefix, pfx) == 0 &&
                        strcmp(d->col_name, hdr) == 0) {
                        *(unsigned long *)(d->var + d->offset) = atol(v);
                        if (d->validity_offset != 0) {
                           *(short *)(d->var + d->validity_offset) = 1;
                        }
                        break;
                    }
                }
                if (d == end)
                    DEBUGMSGTL(("mibII/kernel_linux", "Skipped %s %s %s\n", pfx,
                                hdr, v));
            }
        }
    }
    fclose(in);

    /*
     * Tweak illegal values:
     *
     * valid values for ipForwarding are 1 == yup, 2 == nope
     * a 0 is forbidden, so patch:
     */
    if (!cached_ip_mib.ipForwarding)
        cached_ip_mib.ipForwarding = 2;

    /*
     * 0 is illegal for tcpRtoAlgorithm
     * so assume `other' algorithm:
     */
    if (!cached_tcp_mib.tcpRtoAlgorithm)
        cached_tcp_mib.tcpRtoAlgorithm = 1;

    return ret;
}

int
linux_read_ip_stat(struct ip_mib *ipstat)
{
    memset((char *) ipstat, (0), sizeof(*ipstat));
    if (linux_read_mibII_stats() == -1)
        return -1;
    memcpy((char *) ipstat, (char *) &cached_ip_mib, sizeof(*ipstat));
    return 0;
}

#ifndef NETSNMP_FEATURE_REMOVE_LINUX_READ_IP6_STAT
int linux_read_ip6_stat( struct ip6_mib *ip6stat)
{
#ifdef NETSNMP_ENABLE_IPV6
    FILE           *in;
    char            line[1024];
    unsigned long   stats;
    char           *endp;
    int             match;
#endif

    memset((char *) ip6stat, (0), sizeof(*ip6stat));

#ifdef NETSNMP_ENABLE_IPV6
    DEBUGMSGTL(("mibII/kernel_linux/ip6stats",
                "Reading /proc/net/snmp6 stats\n"));
    if (NULL == (in = fopen("/proc/net/snmp6", "r"))) {
        DEBUGMSGTL(("mibII/kernel_linux/ip6stats",
                    "Failed to open /proc/net/snmp6\n"));
        return -1;
    }

    while (NULL != fgets(line, sizeof(line), in)) {
        if (0 != strncmp(line, IP6_STATS_LINE, IP6_STATS_PREFIX_LEN))
            continue;

        if (1 != sscanf(line, "%*s %lu", &stats))
            continue;

        endp = strchr(line, ' ');
        if (endp)
            *endp = '\0';
        DEBUGMSGTL(("mibII/kernel_linux/ip6stats", "Find tag: %s\n", line));

        match = 1;
        if (0 == strncmp(line + 3, "In", 2)) {  /* In */
            if (0 == strcmp(line + 5, "AddrErrors")) {
                cached_ip6_mib.ip6InAddrErrors = stats;
            } else if (0 == strcmp(line + 5, "Delivers")) {
                cached_ip6_mib.ip6InDelivers = stats;
            } else if (0 == strcmp(line + 5, "Discards")) {
                cached_ip6_mib.ip6InDiscards = stats;
            } else if (0 == strcmp(line + 5, "HdrErrors")) {
                cached_ip6_mib.ip6InHdrErrors = stats;
            } else if (0 == strcmp(line + 5, "McastPkts")) {
                cached_ip6_mib.ip6InMcastPkts = stats;
            } else if (0 == strcmp(line + 5, "NoRoutes")) {
                cached_ip6_mib.ip6InNoRoutes = stats;
            } else if (0 == strcmp(line + 5, "Receives")) {
                cached_ip6_mib.ip6InReceives = stats;
            } else if (0 == strcmp(line + 5, "TruncatedPkts")) {
                cached_ip6_mib.ip6InTruncatedPkts = stats;
            } else if (0 == strcmp(line + 5, "TooBigErrors")) {
                cached_ip6_mib.ip6InTooBigErrors = stats;
            } else if (0 == strcmp(line + 5, "UnknownProtos")) {
                cached_ip6_mib.ip6InUnknownProtos = stats;
            } else {
                match = 0;
            }
        } else if (0 == strncmp(line + 3, "Out", 3)) {  /* Out */
            if (0 == strcmp(line + 6, "Discards")) {
                cached_ip6_mib.ip6OutDiscards = stats;
            } else if (0 == strcmp(line + 6, "ForwDatagrams")) {
                cached_ip6_mib.ip6OutForwDatagrams = stats;
            } else if (0 == strcmp(line + 6, "McastPkts")) {
                cached_ip6_mib.ip6OutMcastPkts = stats;
            } else if (0 == strcmp(line + 6, "NoRoutes")) {
                cached_ip6_mib.ip6OutNoRoutes = stats;
            } else if (0 == strcmp(line + 6, "Requests")) {
                cached_ip6_mib.ip6OutRequests = stats;
            } else {
                match = 0;
            }
        } else if (0 == strncmp(line + 3, "Reasm", 5)) {  /* Reasm */
            if (0 == strcmp(line + 8, "Fails")) {
                cached_ip6_mib.ip6ReasmFails = stats;
            } else if (0 == strcmp(line + 8, "OKs")) {
                cached_ip6_mib.ip6ReasmOKs = stats;
            } else if (0 == strcmp(line + 8, "Reqds")) {
                cached_ip6_mib.ip6ReasmReqds = stats;
            } else if (0 == strcmp(line + 8, "Timeout")) {
                cached_ip6_mib.ip6ReasmTimeout = stats;
            } else {
                match = 0;
            }
        } else if (0 == strncmp(line + 3, "Frag", 4)) {  /* Frag */
            if (0 == strcmp(line + 7, "Creates")) {
                cached_ip6_mib.ip6FragCreates = stats;
            } else if (0 == strcmp(line + 7, "Fails")) {
                cached_ip6_mib.ip6FragFails = stats;
            } else if (0 == strcmp(line + 7, "OKs")) {
                cached_ip6_mib.ip6FragOKs = stats;
            } else {
                match = 0;
            }
        } else {
            match = 0;
        }

        if(!match)
            DEBUGMSGTL(("mibII/kernel_linux/ip6stats",
                        "%s is an unknown tag\n", line));
    }

    fclose(in);
#endif

    memcpy((char *) ip6stat, (char *) &cached_ip6_mib, sizeof(*ip6stat));
    return 0;
}
#endif /* NETSNMP_FEATURE_REMOVE_LINUX_READ_IP6_STAT */

int
linux_read_icmp_msg_stat(struct icmp_mib *icmpstat,
                         struct icmp4_msg_mib *icmpmsgstat,
                         int *flag)
{
    int ret;

    memset(icmpstat, 0, sizeof(*icmpstat));
    memset(icmpmsgstat, 0, sizeof(*icmpmsgstat));

    if ((ret = linux_read_mibII_stats()) == -1) {
        return -1;
    } else if (ret) {
       memcpy(icmpmsgstat, &cached_icmp4_msg_mib, sizeof(*icmpmsgstat));
       *flag = 1; /* We have a valid icmpmsg */
    }

    memcpy(icmpstat, &cached_icmp_mib, sizeof(*icmpstat));
    return 0;
}

int
linux_read_icmp_stat(struct icmp_mib *icmpstat)
{
    memset((char *) icmpstat, (0), sizeof(*icmpstat));
    if (linux_read_mibII_stats() == -1)
        return -1;
    memcpy((char *) icmpstat, (char *) &cached_icmp_mib,
           sizeof(*icmpstat));
    return 0;
}

static int
linux_read_icmp6_parse(struct icmp6_mib *icmp6stat,
                       struct icmp6_msg_mib *icmp6msgstat,
                       int *support)
{
#ifdef NETSNMP_ENABLE_IPV6
    FILE           *in;
    char            line[1024];
    char            name[255];
    unsigned long   stats;
    char           *endp, *vals;
    int             match;
#endif

    memset(icmp6stat, 0, sizeof(*icmp6stat));
    if (NULL != icmp6msgstat)
        memset(icmp6msgstat, 0, sizeof(*icmp6msgstat));

#ifdef NETSNMP_ENABLE_IPV6
    DEBUGMSGTL(("mibII/kernel_linux/icmp6stats",
                "Reading /proc/net/snmp6 stats\n"));
    if (NULL == (in = fopen("/proc/net/snmp6", "r"))) {
        DEBUGMSGTL(("mibII/kernel_linux/icmp6stats",
                    "Failed to open /proc/net/snmp6\n"));
        return -1;
    }

    while (NULL != fgets(line, sizeof(line), in)) {
        if (0 != strncmp(line, ICMP6_STATS_LINE, ICMP6_STATS_PREFIX_LEN))
            continue;

        if (2 != sscanf(line, "%s %lu", name, &stats))
            continue;

        endp = strchr(line, ' ');
        if (endp)
            *endp = '\0';
        DEBUGMSGTL(("mibII/kernel_linux/icmp6stats", "Find tag: %s\n", line));

        vals = name;
        if (NULL != icmp6msgstat) {
            int type;
            if (0 == strncmp(name, "Icmp6OutType", 12)) {
                strsep(&vals, "e");
                type = atoi(vals);
                if ( type < 0 || type > 255 )
                    continue;
                icmp6msgstat->vals[type].OutType = stats;
                *support = 1;
                continue;
            } else if (0 == strncmp(name, "Icmp6InType", 11)) {
                strsep(&vals, "e");
                type = atoi(vals);
                if ( type < 0 || type > 255 )
                    continue;
                icmp6msgstat->vals[type].InType = stats;
                *support = 1;
                continue;
            }
        }

        match = 1;
        if (0 == strncmp(line + 5, "In", 2)) {  /* In */
            if (0 == strcmp(line + 7, "DestUnreachs")) {
                cached_icmp6_mib.icmp6InDestUnreachs = stats;
            } else if (0 == strcmp(line + 7, "Echos")) {
                cached_icmp6_mib.icmp6InEchos = stats;
            } else if (0 == strcmp(line + 7, "EchoReplies")) {
                cached_icmp6_mib.icmp6InEchoReplies = stats;
            } else if (0 == strcmp(line + 7, "Errors")) {
                cached_icmp6_mib.icmp6InErrors = stats;
            } else if (0 == strcmp(line + 7, "GroupMembQueries")) {
                cached_icmp6_mib.icmp6InGroupMembQueries = stats;
            } else if (0 == strcmp(line + 7, "GroupMembReductions")) {
                cached_icmp6_mib.icmp6InGroupMembReductions = stats;
            } else if (0 == strcmp(line + 7, "GroupMembResponses")) {
                cached_icmp6_mib.icmp6InGroupMembResponses = stats;
            } else if (0 == strcmp(line + 7, "Msgs")) {
                cached_icmp6_mib.icmp6InMsgs = stats;
            } else if (0 == strcmp(line + 7, "NeighborAdvertisements")) {
                cached_icmp6_mib.icmp6InNeighborAdvertisements = stats;
            } else if (0 == strcmp(line + 7, "NeighborSolicits")) {
                cached_icmp6_mib.icmp6InNeighborSolicits = stats;
            } else if (0 == strcmp(line + 7, "PktTooBigs")) {
                cached_icmp6_mib.icmp6InPktTooBigs = stats;
            } else if (0 == strcmp(line + 7, "ParmProblems")) {
                cached_icmp6_mib.icmp6InParmProblems = stats;
            } else if (0 == strcmp(line + 7, "Redirects")) {
                cached_icmp6_mib.icmp6InRedirects = stats;
            } else if (0 == strcmp(line + 7, "RouterAdvertisements")) {
                cached_icmp6_mib.icmp6InRouterAdvertisements = stats;
            } else if (0 == strcmp(line + 7, "RouterSolicits")) {
                cached_icmp6_mib.icmp6InRouterSolicits = stats;
            } else if (0 == strcmp(line + 7, "TimeExcds")) {
                cached_icmp6_mib.icmp6InTimeExcds = stats;
            } else {
                match = 0;
            }
        } else if (0 == strncmp(line + 5, "Out", 3)) {  /* Out */
            if (0 == strcmp(line + 8, "DestUnreachs")) {
                cached_icmp6_mib.icmp6OutDestUnreachs = stats;
            } else if (0 == strcmp(line + 8, "Echos")) {
                cached_icmp6_mib.icmp6OutEchos = stats;
            } else if (0 == strcmp(line + 8, "EchoReplies")) {
                cached_icmp6_mib.icmp6OutEchoReplies = stats;
            } else if (0 == strcmp(line + 8, "GroupMembReductions")) {
                cached_icmp6_mib.icmp6OutGroupMembReductions = stats;
            } else if (0 == strcmp(line + 8, "GroupMembResponses")) {
                cached_icmp6_mib.icmp6OutGroupMembResponses = stats;
            } else if (0 == strcmp(line + 8, "Msgs")) {
                cached_icmp6_mib.icmp6OutMsgs = stats;
            } else if (0 == strcmp(line + 8, "NeighborAdvertisements")) {
                cached_icmp6_mib.icmp6OutNeighborAdvertisements = stats;
            } else if (0 == strcmp(line + 8, "NeighborSolicits")) {
                cached_icmp6_mib.icmp6OutNeighborSolicits = stats;
            } else if (0 == strcmp(line + 8, "PktTooBigs")) {
                cached_icmp6_mib.icmp6OutPktTooBigs = stats;
            } else if (0 == strcmp(line + 8, "ParmProblems")) {
                cached_icmp6_mib.icmp6OutParmProblems = stats;
            } else if (0 == strcmp(line + 8, "Redirects")) {
                cached_icmp6_mib.icmp6OutRedirects = stats;
            } else if (0 == strcmp(line + 8, "RouterSolicits")) {
                cached_icmp6_mib.icmp6OutRouterSolicits = stats;
            } else if (0 == strcmp(line + 8, "TimeExcds")) {
                cached_icmp6_mib.icmp6OutTimeExcds = stats;
            } else {
                match = 0;
            }
        } else {
            match = 0;
        }
        if(!match)
            DEBUGMSGTL(("mibII/kernel_linux/icmp6stats",
                        "%s is an unknown tag\n", line));
    }

    fclose(in);
#endif

    memcpy((char *) icmp6stat, (char *) &cached_icmp6_mib,
           sizeof(*icmp6stat));
    return 0;
}

int
linux_read_icmp6_msg_stat(struct icmp6_mib *icmp6stat,
                          struct icmp6_msg_mib *icmp6msgstat,
                          int *support)
{
     if (linux_read_icmp6_parse(icmp6stat, icmp6msgstat, support) < 0)
         return -1;
     else
         return 0;
}

int
linux_read_icmp6_stat(struct icmp6_mib *icmp6stat)
{
   if (linux_read_icmp6_parse(icmp6stat, NULL, NULL) < 0)
       return -1;
   else
       return 0;
}

int
linux_read_tcp_stat(struct tcp_mib *tcpstat)
{
    memset((char *) tcpstat, (0), sizeof(*tcpstat));
    if (linux_read_mibII_stats() == -1)
        return -1;
    memcpy((char *) tcpstat, (char *) &cached_tcp_mib, sizeof(*tcpstat));
    return 0;
}

int
linux_read_udp_stat(struct udp_mib *udpstat)
{
    memset((char *) udpstat, (0), sizeof(*udpstat));
    if (linux_read_mibII_stats() == -1)
        return -1;

#ifdef NETSNMP_ENABLE_IPV6
    {
        struct udp6_mib udp6stat;
        memset(&udp6stat, 0, sizeof(udp6stat));

        if (linux_read_udp6_stat(&udp6stat) == 0) {
            cached_udp_mib.udpOutDatagrams += udp6stat.udp6OutDatagrams;
            cached_udp_mib.udpNoPorts      += udp6stat.udp6NoPorts;
            cached_udp_mib.udpInDatagrams  += udp6stat.udp6InDatagrams;
            cached_udp_mib.udpInErrors     += udp6stat.udp6InErrors;
        }
    }
#endif
    memcpy((char *) udpstat, (char *) &cached_udp_mib, sizeof(*udpstat));
    return 0;
}

int
linux_read_udp6_stat(struct udp6_mib *udp6stat)
{
#ifdef NETSNMP_ENABLE_IPV6
    FILE           *in;
    char            line[1024];
    unsigned long   stats;
    char           *endp;
#endif

    memset(udp6stat, 0, sizeof(*udp6stat));

#ifdef NETSNMP_ENABLE_IPV6
    DEBUGMSGTL(("mibII/kernel_linux/udp6stats",
                "Reading /proc/net/snmp6 stats\n"));
    if (NULL == (in = fopen("/proc/net/snmp6", "r"))) {
        DEBUGMSGTL(("mibII/kernel_linux/udp6stats",
                    "Failed to open /proc/net/snmp6\n"));
       return -1;
    }

    while (NULL != fgets(line, sizeof(line), in)) {
        if (0 != strncmp(line, UDP6_STATS_LINE, UDP6_STATS_PREFIX_LEN))
            continue;

        if (1 != sscanf(line, "%*s %lu", &stats))
            continue;

        endp = strchr(line, ' ');
        if (endp)
            *endp = '\0';
        DEBUGMSGTL(("mibII/kernel_linux/udp6stats", "Find tag: %s\n", line));

        if (0 == strcmp(line + 4, "OutDatagrams")) {
            cached_udp6_mib.udp6OutDatagrams = stats;
        } else if (0 == strcmp(line + 4, "NoPorts")) {
            cached_udp6_mib.udp6NoPorts = stats;
        } else if (0 == strcmp(line + 4, "InDatagrams")) {
            cached_udp6_mib.udp6InDatagrams = stats;
        } else if (0 == strcmp(line + 4, "InErrors")) {
            cached_udp6_mib.udp6InErrors = stats;
        } else {
            DEBUGMSGTL(("mibII/kernel_linux/udp6stats",
                        "%s is an unknown tag\n", line));
        }
    }

    fclose(in);
#endif

    memcpy((char *) udp6stat, (char *) &cached_udp6_mib, sizeof(*udp6stat));
    return 0;
}
