ipf/tools/ipnat.c

/*
 * Copyright (C) 1993-2001 by Darren Reed.
 *
 * See the IPFILTER.LICENCE file for details on licencing.
 *
 * Added redirect stuff and a variety of bug fixes. (mcn@EnGarde.com)
 *
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2014, Joyent, Inc.  All rights reserved.
 */

#include <stdio.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>
#if !defined(__SVR4) && !defined(__svr4__)
#include <strings.h>
#else
#include <sys/byteorder.h>
#endif
#include <sys/time.h>
#include <sys/param.h>
#include <stdlib.h>
#include <unistd.h>
#include <stddef.h>
#include <sys/file.h>
#define _KERNEL
#include <sys/uio.h>
#undef _KERNEL
#include <sys/socket.h>
#include <sys/ioctl.h>
#if defined(sun) && (defined(__svr4__) || defined(__SVR4))
# include <sys/ioccom.h>
# include <sys/sysmacros.h>
#endif
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/tcp.h>
#include <net/if.h>
#if __FreeBSD_version >= 300000
# include <net/if_var.h>
#endif
#include <netdb.h>
#include <arpa/nameser.h>
#include <arpa/inet.h>
#include <resolv.h>
#include <ctype.h>
#if defined(linux)
# include <linux/a.out.h>
#else
# include <nlist.h>
#endif
#include "ipf.h"
#include "netinet/ipl.h"
#include "kmem.h"
#include "ipfzone.h"

#ifdef  __hpux
# define    nlist   nlist64
#endif

#if defined(sun) && !SOLARIS2
# define    STRERROR(x) sys_errlist[x]
extern  char    *sys_errlist[];
#else
# define    STRERROR(x) strerror(x)
#endif

#if !defined(lint)
static const char sccsid[] ="@(#)ipnat.c    1.9 6/5/96 (C) 1993 Darren Reed";
static const char rcsid[] = "@(#)$Id: ipnat.c,v 1.24.2.2 2005/05/10 21:19:30 darrenr Exp $";
#endif


#if SOLARIS
#define bzero(a,b)  memset(a,0,b)
#endif
int use_inet6 = 0;
char    thishost[MAXHOSTNAMELEN];

extern  char    *optarg;

void    dostats __P((int, natstat_t *, int, int));
void    flushtable __P((int, int));
void    usage __P((char *));
int main __P((int, char*[]));
void    showhostmap __P((natstat_t *nsp));
void    natstat_dead __P((natstat_t *, char *));
void    dostats_live __P((int, natstat_t *, int));
void    showhostmap_live __P((int, natstat_t *));

int opts;

void usage(name)
char *name;
{
    fprintf(stderr, "Usage: %s [-CdFhlnrRsv] [-f filename]", name);
    fprintf(stderr, " [-G|-z zonename]\n");
    exit(1);
}


int main(argc, argv)
int argc;
char *argv[];
{
    char *file, *core, *kernel;
    natstat_t ns, *nsp;
    int fd, c, mode;
    ipfobj_t obj;

    fd = -1;
    opts = 0;
    nsp = &ns;
    file = NULL;
    core = NULL;
    kernel = NULL;
    mode = O_RDWR;

    while ((c = getopt(argc, argv, "CdFf:G:hlM:N:nrRsvz:")) != -1)
        switch (c)
        {
        case 'C' :
            opts |= OPT_CLEAR;
            break;
        case 'd' :
            opts |= OPT_DEBUG;
            break;
        case 'f' :
            file = optarg;
            break;
        case 'F' :
            opts |= OPT_FLUSH;
            break;
        case 'G' :
            setzonename_global(optarg);
            break;
        case 'h' :
            opts |=OPT_HITS;
            break;
        case 'l' :
            opts |= OPT_LIST;
            mode = O_RDONLY;
            break;
        case 'M' :
            core = optarg;
            break;
        case 'N' :
            kernel = optarg;
            break;
        case 'n' :
            opts |= OPT_DONOTHING;
            mode = O_RDONLY;
            break;
        case 'R' :
            opts |= OPT_NORESOLVE;
            break;
        case 'r' :
            opts |= OPT_REMOVE;
            break;
        case 's' :
            opts |= OPT_STAT;
            mode = O_RDONLY;
            break;
        case 'v' :
            opts |= OPT_VERBOSE;
            break;
        case 'z' :
            setzonename(optarg);
            break;
        default :
            usage(argv[0]);
        }

    initparse();

    if ((kernel != NULL) || (core != NULL)) {
        (void) setgid(getgid());
        (void) setreuid(getuid(), getuid());
    }

    bzero((char *)&ns, sizeof(ns));

    if ((opts & OPT_DONOTHING) == 0) {
        if (checkrev(IPL_NAME) == -1) {
            fprintf(stderr, "User/kernel version check failed\n");
            exit(1);
        }
    }


    if (!(opts & OPT_DONOTHING) && (kernel == NULL) && (core == NULL)) {
#ifdef notdef
        if (openkmem(kernel, core) == -1)
            exit(1);
#endif
        if (((fd = open(IPNAT_NAME, mode)) == -1) &&
            ((fd = open(IPNAT_NAME, O_RDONLY)) == -1)) {
            (void) fprintf(stderr, "%s: open: %s\n", IPNAT_NAME,
                STRERROR(errno));
            exit(1);
        }

        if (setzone(fd) != 0) {
            close(fd);
            exit(1);
        }

        bzero((char *)&obj, sizeof(obj));
        obj.ipfo_rev = IPFILTER_VERSION;
        obj.ipfo_size = sizeof(*nsp);
        obj.ipfo_type = IPFOBJ_NATSTAT;
        obj.ipfo_ptr = (void *)nsp;
        if (ioctl(fd, SIOCGNATS, &obj) == -1) {
            perror("ioctl(SIOCGNATS)");
            exit(1);
        }
        (void) setgid(getgid());
        (void) setreuid(getuid(), getuid());
    } else if ((kernel != NULL) || (core != NULL)) {
        if (openkmem(kernel, core) == -1)
            exit(1);

        natstat_dead(nsp, kernel);
        if (opts & (OPT_LIST|OPT_STAT))
            dostats(fd, nsp, opts, 0);
        exit(0);
    }

    if (opts & (OPT_FLUSH|OPT_CLEAR))
        flushtable(fd, opts);
    if (file) {
        ipnat_parsefile(fd, ipnat_addrule, ioctl, file);
    }
    if (opts & (OPT_LIST|OPT_STAT))
        dostats(fd, nsp, opts, 1);
    return 0;
}


/*
 * Read NAT statistic information in using a symbol table and memory file
 * rather than doing ioctl's.
 */
void natstat_dead(nsp, kernel)
natstat_t *nsp;
char *kernel;
{
    struct nlist nat_nlist[10] = {
        { "nat_table" },        /* 0 */
        { "nat_list" },
        { "maptable" },
        { "ipf_nattable_sz" },
        { "ipf_natrules_sz" },
        { "ipf_rdrrules_sz" },      /* 5 */
        { "ipf_hostmap_sz" },
        { "nat_instances" },
        { "ap_sess_list" },
        { NULL }
    };
    void *tables[2];

    if (nlist(kernel, nat_nlist) == -1) {
        fprintf(stderr, "nlist error\n");
        return;
    }

    /*
     * Normally the ioctl copies all of these values into the structure
     * for us, before returning it to userland, so here we must copy each
     * one in individually.
     */
    kmemcpy((char *)&tables, nat_nlist[0].n_value, sizeof(tables));
    nsp->ns_table[0] = tables[0];
    nsp->ns_table[1] = tables[1];

    kmemcpy((char *)&nsp->ns_list, nat_nlist[1].n_value,
        sizeof(nsp->ns_list));
    kmemcpy((char *)&nsp->ns_maptable, nat_nlist[2].n_value,
        sizeof(nsp->ns_maptable));
    kmemcpy((char *)&nsp->ns_nattab_sz, nat_nlist[3].n_value,
        sizeof(nsp->ns_nattab_sz));
    kmemcpy((char *)&nsp->ns_rultab_sz, nat_nlist[4].n_value,
        sizeof(nsp->ns_rultab_sz));
    kmemcpy((char *)&nsp->ns_rdrtab_sz, nat_nlist[5].n_value,
        sizeof(nsp->ns_rdrtab_sz));
    kmemcpy((char *)&nsp->ns_hostmap_sz, nat_nlist[6].n_value,
        sizeof(nsp->ns_hostmap_sz));
    kmemcpy((char *)&nsp->ns_instances, nat_nlist[7].n_value,
        sizeof(nsp->ns_instances));
    kmemcpy((char *)&nsp->ns_apslist, nat_nlist[8].n_value,
        sizeof(nsp->ns_apslist));
}


/*
 * Display NAT statistics.
 */
void dostats(fd, nsp, opts, alive)
natstat_t *nsp;
int fd, opts, alive;
{
    nat_t *np, nat;
    ipnat_t ipn;

    /*
     * Show statistics ?
     */
    if (opts & OPT_STAT) {
        printf("mapped\tin\t%lu\tout\t%lu\n",
            nsp->ns_mapped[0], nsp->ns_mapped[1]);
        printf("added\t%lu\texpired\t%lu\n",
            nsp->ns_added, nsp->ns_expire);
        printf("no memory\t%lu\tbad nat\t%lu\n",
            nsp->ns_memfail, nsp->ns_badnat);
        printf("inuse\t%lu\norphans\t%u\nrules\t%lu\n",
            nsp->ns_inuse, nsp->ns_orphans, nsp->ns_rules);
        printf("wilds\t%u\n", nsp->ns_wilds);
        if (opts & OPT_VERBOSE)
            printf("table %p list %p\n",
                nsp->ns_table, nsp->ns_list);
    }

    /*
     * Show list of NAT rules and NAT sessions ?
     */
    if (opts & OPT_LIST) {
        if (alive) {
            dostats_live(fd, nsp, opts);
            return;
        }
        printf("List of active MAP/Redirect filters:\n");
        while (nsp->ns_list) {
            if (kmemcpy((char *)&ipn, (long)nsp->ns_list,
                    sizeof(ipn))) {
                perror("kmemcpy");
                break;
            }
            if (opts & OPT_HITS)
                printf("%lu ", ipn.in_hits);
            printnat(&ipn, opts & (OPT_DEBUG|OPT_VERBOSE));
            nsp->ns_list = ipn.in_next;
        }

        printf("\nList of active sessions:\n");

        for (np = nsp->ns_instances; np; np = nat.nat_next) {
            if (kmemcpy((char *)&nat, (long)np, sizeof(nat)))
                break;
            printactivenat(&nat, opts, 0);
            if (nat.nat_aps)
                printaps(nat.nat_aps, opts);
        }

        if (opts & OPT_VERBOSE)
            showhostmap(nsp);
    }
}


/*
 * Display the active host mapping table.
 */
void showhostmap(nsp)
natstat_t *nsp;
{
    hostmap_t hm, *hmp, **maptable;
    u_int hv;

    printf("\nList of active host mappings:\n");

    maptable = (hostmap_t **)malloc(sizeof(hostmap_t *) *
                    nsp->ns_hostmap_sz);
    if (maptable == NULL) {
        perror("malloc");
        exit(1);
    }
    if (kmemcpy((char *)maptable, (u_long)nsp->ns_maptable,
            sizeof(hostmap_t *) * nsp->ns_hostmap_sz)) {
        perror("kmemcpy (maptable)");
        return;
    }

    for (hv = 0; hv < nsp->ns_hostmap_sz; hv++) {
        hmp = maptable[hv];

        while (hmp) {
            if (kmemcpy((char *)&hm, (u_long)hmp, sizeof(hm))) {
                perror("kmemcpy (hostmap)");
                return;
            }

            printhostmap(&hm, hv);
            hmp = hm.hm_next;
        }
    }
    free(maptable);
}


/*
 * Issue an ioctl to flush either the NAT rules table or the active mapping
 * table or both.
 */
void flushtable(fd, opts)
int fd, opts;
{
    int n = 0;

    if (opts & OPT_FLUSH) {
        n = FLUSH_TABLE_ALL;
        if (!(opts & OPT_DONOTHING) && ioctl(fd, SIOCIPFFL, &n) == -1)
            perror("ioctl(SIOCFLNAT)");
        else
            printf("%d entries flushed from NAT table\n", n);
    }

    if (opts & OPT_CLEAR) {
        n = FLUSH_LIST;
        if (!(opts & OPT_DONOTHING) && ioctl(fd, SIOCIPFFL, &n) == -1)
            perror("ioctl(SIOCCNATL)");
        else
            printf("%d entries flushed from NAT list\n", n);
    }
}

/*
 * Display NAT statistics.
 */
void dostats_live(fd, nsp, opts)
natstat_t *nsp;
int fd, opts;
{
    ipfgeniter_t iter;
    ipfobj_t obj;
    ipnat_t ipn;
    nat_t nat;

    bzero((char *)&obj, sizeof(obj));
    obj.ipfo_rev = IPFILTER_VERSION;
    obj.ipfo_type = IPFOBJ_GENITER;
    obj.ipfo_size = sizeof(iter);
    obj.ipfo_ptr = &iter;

    iter.igi_type = IPFGENITER_IPNAT;
    iter.igi_nitems = 1;
    iter.igi_data = &ipn;

    /*
     * Show list of NAT rules and NAT sessions ?
     */
    printf("List of active MAP/Redirect filters:\n");
    while (nsp->ns_list) {
        if (ioctl(fd, SIOCGENITER, &obj) == -1)
            break;
        if (opts & OPT_HITS)
            printf("%lu ", ipn.in_hits);
        printnat(&ipn, opts & (OPT_DEBUG|OPT_VERBOSE));
        nsp->ns_list = ipn.in_next;
    }

    printf("\nList of active sessions:\n");

    iter.igi_type = IPFGENITER_NAT;
    iter.igi_nitems = 1;
    iter.igi_data = &nat;

    while (nsp->ns_instances != NULL) {
        if (ioctl(fd, SIOCGENITER, &obj) == -1)
            break;
        printactivenat(&nat, opts, 1);
        if (nat.nat_aps)
            printaps(nat.nat_aps, opts);
        nsp->ns_instances = nat.nat_next;
    }

    if (opts & OPT_VERBOSE)
        showhostmap_live(fd, nsp);
}

/*
 * Display the active host mapping table.
 */
void showhostmap_live(fd, nsp)
int fd;
natstat_t *nsp;
{
    hostmap_t hm, *hmp;
    ipfgeniter_t iter;
    ipfobj_t obj;

    bzero((char *)&obj, sizeof(obj));
    obj.ipfo_rev = IPFILTER_VERSION;
    obj.ipfo_type = IPFOBJ_GENITER;
    obj.ipfo_size = sizeof(iter);
    obj.ipfo_ptr = &iter;

    iter.igi_type = IPFGENITER_HOSTMAP;
    iter.igi_nitems = 1;
    iter.igi_data = &hm;

    printf("\nList of active host mappings:\n");

    while (nsp->ns_maplist != NULL) {
        if (ioctl(fd, SIOCGENITER, &obj) == -1)
            break;
        printhostmap(&hm, 0);
        nsp->ns_maplist = hm.hm_next;
    }
}