/*
 * Copyright (c) 1983, 1988, 1993
 *      Regents of the University of California.  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 name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 * @(#) Copyright (c) 1983, 1988, 1993 Regents of the University of California.  All rights reserved.
 * @(#)main.c   8.4 (Berkeley) 3/1/94
 * $FreeBSD: src/usr.bin/netstat/main.c,v 1.34.2.12 2001/09/17 15:17:46 ru Exp $
 */

#include <sys/param.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/sysctl.h>

#include <netinet/in.h>

#include <netgraph/socket/ng_socket.h>

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <limits.h>
#include <netdb.h>
#include <nlist.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "netstat.h"

static struct nlist nl[] = {
#define N_IFNET         0
        { .n_name = "_ifnet" },
#define N_UNIXSW        1
        { .n_name = "_localsw" },
#define N_RTREE         2
        { .n_name = "_rt_tables"},
#define N_CLTPSTAT      3
        { .n_name = "_cltpstat"},
#define N_MRTSTAT       4
        { .n_name = "_mrtstat" },
#define N_MFCTABLE      5
        { .n_name = "_mfctable" },
#define N_VIFTABLE      6
        { .n_name = "_viftable" },
#define N_NGSOCKS       7
        { .n_name = "_ngsocklist"},
#define N_IP6STAT       8
        { .n_name = "_ip6stat" },
#define N_ICMP6STAT     9
        { .n_name = "_icmp6stat" },
#define N_PIM6STAT      10
        { .n_name = "_pim6stat" },
#define N_MRT6PROTO     11
        { .n_name = "_ip6_mrtproto" },
#define N_MRT6STAT      12
        { .n_name = "_mrt6stat" },
#define N_MF6CTABLE     13
        { .n_name = "_mf6ctable" },
#define N_MIF6TABLE     14
        { .n_name = "_mif6table" },
#define N_MBSTAT        15
        { .n_name = "_mbstat" },
#define N_MBTYPES       16
        { .n_name = "_mbtypes" },
#define N_NMBCLUSTERS   17
        { .n_name = "_nmbclusters" },
#define N_NMBUFS        18
        { .n_name = "_nmbufs" },
#define N_NCPUS         19
        { .n_name = "_ncpus" },
#define N_CARPSTAT      20
        { .n_name = "_carpstats" },
#define N_NMBJCLUSTERS  21
        { .n_name = "_nmbjclusters" },
        { .n_name = NULL },
};

struct protox {
        u_char  pr_index;               /* index into nlist of cb head */
        u_char  pr_sindex;              /* index into nlist of stat block */
        u_char  pr_wanted;              /* 1 if wanted, 0 otherwise */
        void    (*pr_cblocks)(u_long, const char *, int);
                                        /* control blocks printing routine */
        void    (*pr_stats)(u_long, const char *, int);
                                        /* statistics printing routine */
        void    (*pr_istats)(char *);   /* per/if statistics printing routine */
        const char *pr_name;            /* well-known name */
        u_int   pr_usesysctl;           /* true if we use sysctl, not kvm */
} protox[] = {
        { -1,           -1,             1,      protopr,
          tcp_stats,    NULL,           "tcp",  IPPROTO_TCP },
        { -1,           -1,             1,      protopr,
          udp_stats,    NULL,           "udp",  IPPROTO_UDP },
        { -1,           -1,             1,      protopr,
          NULL,         NULL,           "divert",IPPROTO_DIVERT },
        { -1,           -1,             1,      protopr,
          ip_stats,     NULL,           "ip",   IPPROTO_RAW },
        { -1,           -1,             1,      protopr,
          icmp_stats,   NULL,           "icmp", IPPROTO_ICMP },
        { -1,           -1,             1,      protopr,
          igmp_stats,   NULL,           "igmp", IPPROTO_IGMP },
        { -1,           N_CARPSTAT,     1,      0,
          carp_stats,   NULL,           "carp",         0},
        { -1,           -1,             0,      0,
          0,            NULL,           NULL,           0}
};

#ifdef INET6
struct protox ip6protox[] = {
        { -1,           -1,             1,      protopr,
          tcp_stats,    NULL,           "tcp",  IPPROTO_TCP },
        { -1,           -1,             1,      protopr,
          udp_stats,    NULL,           "udp",  IPPROTO_UDP },
        { -1,           N_IP6STAT,      1,      protopr,
          ip6_stats,    ip6_ifstats,    "ip6",  IPPROTO_RAW },
        { -1,           N_ICMP6STAT,    1,      protopr,
          icmp6_stats,  icmp6_ifstats,  "icmp6",IPPROTO_ICMPV6 },
#ifdef notyet
        { -1,           N_PIM6STAT,     1,      0,
          pim6_stats,   NULL,           "pim6", 0 },
#endif
        { -1,           -1,             1,      0,
          rip6_stats,   NULL,           "rip6", 0 },
        { -1,           -1,             1,      protopr,
          pim_stats,    NULL,           "pim",  IPPROTO_PIM },
        { -1,           -1,             0,      0,
          0,            NULL,           0,      0 }
};
#endif /*INET6*/

struct protox netgraphprotox[] = {
        { N_NGSOCKS,    -1,             1,      netgraphprotopr,
          NULL,         NULL,           "ctrl", 0 },
        { N_NGSOCKS,    -1,             1,      netgraphprotopr,
          NULL,         NULL,           "data", 0 },
        { -1,           -1,             0,      0,
          0,            NULL,           NULL,   0 }
};

struct protox *protoprotox[] = {
                                         protox,
#ifdef INET6
                                         ip6protox,
#endif
                                         NULL };

static void printproto (struct protox *, const char *, u_long);
static void usage (void);
static struct protox *name2protox (char *);
static struct protox *knownname (char *);

static kvm_t *kvmd;
static char *nlistf = NULL, *memf = NULL;

int     Aflag;          /* show addresses of protocol control block */
int     aflag;          /* show all sockets (including servers) */
int     bflag;          /* show i/f total bytes in/out */
int     cpuflag = -1;   /* dump route table from specific cpu */
int     dflag;          /* show i/f dropped packets */
int     gflag;          /* show group (multicast) routing or stats */
int     hflag;          /* show counters in human readable format */
int     iflag;          /* show interfaces */
int     Lflag;          /* show size of listen queues */
int     mflag;          /* show memory stats */
int     Pflag;          /* show more protocol info (go past 80 columns) */
int     numeric_addr;   /* show addresses numerically */
int     numeric_port;   /* show ports numerically */
static int pflag;       /* show given protocol */
int     rflag;          /* show routing tables (or routing stats) */
int     sflag;          /* show protocol statistics */
int     tflag;          /* show i/f watchdog timers */
int     Bflag;          /* show buffer limit instead of buffer use */
int     Wflag;          /* wide display */
int     zflag;          /* zero stats */

int     interval;       /* repeat interval for i/f stats */

char    *interface;     /* desired i/f for stats, or NULL for all i/fs */
int     unit;           /* unit number for above */

int     af;             /* address family */

int
main(int argc, char **argv)
{
        struct protox *tp = NULL;  /* for printing cblocks & stats */
        int ch;
        int n;
        size_t nsz;

        af = AF_UNSPEC;

        while ((ch = getopt(argc, argv, "46Aabc:df:ghI:iLlM:mN:nPp:rSsBtuWw:z")) != -1)
                switch(ch) {
                case '4':
                        af = AF_INET;
                        break;
#ifdef INET6
                case '6':
                        af = AF_INET6;
                        break;
#endif /*INET6*/
                case 'A':
                        Aflag = 1;
                        break;
                case 'a':
                        aflag = 1;
                        break;
                case 'b':
                        bflag = 1;
                        break;
                case 'c':
                        nsz = sizeof(n);
                        sysctlbyname("net.netisr.ncpus", &n, &nsz, NULL, 0);
                        cpuflag = strtol(optarg, NULL, 0);
                        if (cpuflag < 0 || cpuflag >= n) {
                                errx(1, "cpu%d does not have network data",
                                    cpuflag);
                        }
                        break;
                case 'd':
                        dflag = 1;
                        break;
                case 'f':
                        if (strcmp(optarg, "inet") == 0)
                                af = AF_INET;
#ifdef INET6
                        else if (strcmp(optarg, "inet6") == 0)
                                af = AF_INET6;
#endif /*INET6*/
                        else if (strcmp(optarg, "unix") == 0)
                                af = AF_UNIX;
                        else if (strcmp(optarg, "ng") == 0
                            || strcmp(optarg, "netgraph") == 0)
                                af = AF_NETGRAPH;
                        else if (strcmp(optarg, "link") == 0)
                                af = AF_LINK;
                        else if (strcmp(optarg, "mpls") == 0)
                                af = AF_MPLS;
                        else {
                                errx(1, "%s: unknown address family", optarg);
                        }
                        break;
                case 'g':
                        gflag = 1;
                        break;
                case 'h':
                        hflag = 1;
                        break;
                case 'I': {
                        char *cp;

                        iflag = 1;
                        for (cp = interface = optarg; isalpha(*cp); cp++)
                                continue;
                        unit = atoi(cp);
                        break;
                }
                case 'i':
                        iflag = 1;
                        break;
                case 'L':
                        Lflag = 1;
                        break;
                case 'M':
                        memf = optarg;
                        break;
                case 'm':
                        mflag = 1;
                        break;
                case 'N':
                        nlistf = optarg;
                        break;
                case 'n':
                        numeric_addr = numeric_port = 1;
                        break;
                case 'P':
                        Pflag = 1;
                        break;
                case 'p':
                        if ((tp = name2protox(optarg)) == NULL) {
                                errx(1,
                                     "%s: unknown or uninstrumented protocol",
                                     optarg);
                        }
                        pflag = 1;
                        break;
                case 'r':
                        rflag = 1;
                        break;
                case 's':
                        ++sflag;
                        break;
                case 'S':
                        numeric_addr = 1;
                        break;
                case 'B':
                        Bflag = 1;
                        break;
                case 't':
                        tflag = 1;
                        break;
                case 'u':
                        af = AF_UNIX;
                        break;
                case 'W':
                case 'l':
                        Wflag = 1;
                        break;
                case 'w':
                        interval = atoi(optarg);
                        iflag = 1;
                        break;
                case 'z':
                        zflag = 1;
                        break;
                case '?':
                default:
                        usage();
                }
        argv += optind;
        argc -= optind;

#define BACKWARD_COMPATIBILITY
#ifdef  BACKWARD_COMPATIBILITY
        if (*argv) {
                if (isdigit(**argv)) {
                        interval = atoi(*argv);
                        if (interval <= 0)
                                usage();
                        ++argv;
                        iflag = 1;
                }
                if (*argv) {
                        nlistf = *argv;
                        if (*++argv)
                                memf = *argv;
                }
        }
#endif

        /*
         * Discard setgid privileges if not the running kernel so that bad
         * guys can't print interesting stuff from kernel memory.
         */
        if (nlistf != NULL || memf != NULL)
                setgid(getgid());

        if (mflag) {
                if (memf != NULL) {
                        if (kread(0, 0, 0) == 0)
                                mbpr(nl[N_MBSTAT].n_value,
                                    nl[N_MBTYPES].n_value,
                                    nl[N_NMBCLUSTERS].n_value,
                                    nl[N_NMBJCLUSTERS].n_value,
                                    nl[N_NMBUFS].n_value,
                                    nl[N_NCPUS].n_value);
                } else {
                        mbpr(0, 0, 0, 0, 0, 0);
                }
                exit(0);
        }
#if 0
        /*
         * Keep file descriptors open to avoid overhead
         * of open/close on each call to get* routines.
         */
        sethostent(1);
        setnetent(1);
#else
        /*
         * This does not make sense any more with DNS being default over
         * the files.  Doing a setXXXXent(1) causes a tcp connection to be
         * used for the queries, which is slower.
         */
#endif
        if (iflag && !sflag) {
                kread(0, 0, 0);
                intpr(interval, nl[N_IFNET].n_value, NULL, nl[N_NCPUS].n_value);
                exit(0);
        }
        if (rflag) {
                kread(0, 0, 0);
                if (sflag)
                        rt_stats();
                else
                        routepr(nl[N_RTREE].n_value);
                exit(0);
        }
        if (gflag) {
                kread(0, 0, 0);
                if (sflag) {
                        if (af == AF_INET || af == AF_UNSPEC)
                                mrt_stats(nl[N_MRTSTAT].n_value);
#ifdef INET6
                        if (af == AF_INET6 || af == AF_UNSPEC)
                                mrt6_stats(nl[N_MRT6STAT].n_value);
#endif
                } else {
                        if (af == AF_INET || af == AF_UNSPEC)
                                mroutepr(nl[N_MFCTABLE].n_value,
                                         nl[N_VIFTABLE].n_value);
#ifdef INET6
                        if (af == AF_INET6 || af == AF_UNSPEC)
                                mroute6pr(nl[N_MF6CTABLE].n_value,
                                          nl[N_MIF6TABLE].n_value);
#endif
                }
                exit(0);
        }

        kread(0, 0, 0);
        if (tp) {
                printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
                exit(0);
        }
        if (af == AF_INET || af == AF_UNSPEC)
                for (tp = protox; tp->pr_name; tp++)
                        printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
#ifdef INET6
        if (af == AF_INET6 || af == AF_UNSPEC)
                for (tp = ip6protox; tp->pr_name; tp++)
                        printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
#endif /*INET6*/
        if (af == AF_NETGRAPH || af == AF_UNSPEC)
                for (tp = netgraphprotox; tp->pr_name; tp++)
                        printproto(tp, tp->pr_name, nl[N_NCPUS].n_value);
        if ((af == AF_UNIX || af == AF_UNSPEC) && !Lflag && !sflag)
                unixpr();
        exit(0);
}

/*
 * Print out protocol statistics or control blocks (per sflag).
 * If the interface was not specifically requested, and the symbol
 * is not in the namelist, ignore this one.
 */
static void
printproto(struct protox *tp, const char *name, u_long ncpusaddr)
{
        void (*pr)(u_long, const char *, int);
        u_long off;

        if (sflag) {
                if (iflag) {
                        if (tp->pr_istats)
                                intpr(interval, nl[N_IFNET].n_value,
                                      tp->pr_istats, ncpusaddr);
                        else if (pflag)
                                printf("%s: no per-interface stats routine\n",
                                    tp->pr_name);
                        return;
                }
                else {
                        pr = tp->pr_stats;
                        if (!pr) {
                                if (pflag)
                                        printf("%s: no stats routine\n",
                                            tp->pr_name);
                                return;
                        }
                        off = tp->pr_usesysctl ? tp->pr_usesysctl
                                : nl[tp->pr_sindex].n_value;
                }
        } else {
                pr = tp->pr_cblocks;
                if (!pr) {
                        if (pflag)
                                printf("%s: no PCB routine\n", tp->pr_name);
                        return;
                }
                off = tp->pr_usesysctl ? tp->pr_usesysctl
                        : nl[tp->pr_index].n_value;
        }
        if (pr != NULL && (off || af != AF_UNSPEC))
                (*pr)(off, name, af);
}

/*
 * Read kernel memory, return 0 on success.
 */
int
kread(u_long addr, char *buf, int size)
{
        if (kvmd == NULL) {
                /*
                 * XXX.
                 */
                kvmd = kvm_openfiles(nlistf, memf, NULL, O_RDONLY, buf);
                if (kvmd != NULL) {
                        if (kvm_nlist(kvmd, nl) < 0) {
                                if (nlistf)
                                        errx(1, "%s: kvm_nlist: %s", nlistf,
                                             kvm_geterr(kvmd));
                                else
                                        errx(1, "kvm_nlist: %s", kvm_geterr(kvmd));
                        }

                        if (nl[0].n_type == 0) {
                                if (nlistf)
                                        errx(1, "%s: no namelist", nlistf);
                                else
                                        errx(1, "no namelist");
                        }
                } else {
                        warnx("kvm not available");
                        return (-1);
                }
        }
        if (!buf)
                return (0);
        if (kvm_read(kvmd, addr, buf, size) != size) {
                warnx("%s", kvm_geterr(kvmd));
                return (-1);
        }
        return (0);
}

const char *
plural(int n)
{
        return (n != 1 ? "s" : "");
}

const char *
plurales(int n)
{
        return (n != 1 ? "es" : "");
}

/*
 * Find the protox for the given "well-known" name.
 */
static struct protox *
knownname(char *name)
{
        struct protox **tpp, *tp;

        for (tpp = protoprotox; *tpp; tpp++)
                for (tp = *tpp; tp->pr_name; tp++)
                        if (strcmp(tp->pr_name, name) == 0)
                                return (tp);
        return (NULL);
}

/*
 * Find the protox corresponding to name.
 */
static struct protox *
name2protox(char *name)
{
        struct protox *tp;
        char **alias;                   /* alias from p->aliases */
        struct protoent *p;

        /*
         * Try to find the name in the list of "well-known" names. If that
         * fails, check if name is an alias for an Internet protocol.
         */
        if ((tp = knownname(name)) != NULL)
                return (tp);

        setprotoent(1);                 /* make protocol lookup cheaper */
        while ((p = getprotoent()) != NULL) {
                /* assert: name not same as p->name */
                for (alias = p->p_aliases; *alias; alias++)
                        if (strcmp(name, *alias) == 0) {
                                endprotoent();
                                return (knownname(p->p_name));
                        }
        }
        endprotoent();
        return (NULL);
}

static void
usage(void)
{
        (void)fprintf(stderr, "%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n%s\n",
"usage: netstat [-AaLnPSW] [-c cpu] [-f protocol_family | -p protocol]\n"
"               [-M core] [-N system]",
"       netstat -i | -I interface [-aBbdhnt] [-f address_family]\n"
"               [-M core] [-N system]",
"       netstat -w wait [-I interface] [-dh] [-M core] [-N system]",
"       netstat -s [-s] [-z] [-f protocol_family | -p protocol] [-M core]",
"       netstat -i | -I interface -s [-f protocol_family | -p protocol]\n"
"               [-M core] [-N system]",
"       netstat -m [-M core] [-N system]",
"       netstat -r [-AanW] [-f address_family] [-M core] [-N system]",
"       netstat -rs [-s] [-M core] [-N system]",
"       netstat -g [-W] [-f address_family] [-M core] [-N system]",
"       netstat -gs [-s] [-f address_family] [-M core] [-N system]");
        exit(1);
}