- Test m_pkthdr.fw_flags against DUMMYNET_MBUF_TAGGED before trying to locate

[dragonfly/netmp.git] / sbin / ifconfig / ifconfig.c

/*
 * Copyright (c) 1983, 1993
 *      The 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.
 * 4. 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.
 *
 * $FreeBSD: src/sbin/ifconfig/ifconfig.c,v 1.113.2.4 2006/02/09 10:48:43 yar Exp $
 * $DragonFly: src/sbin/ifconfig/ifconfig.c,v 1.30 2007/09/30 04:37:27 sephe Exp $
 */

#include <sys/param.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/module.h>
#include <sys/linker.h>

#include <net/ethernet.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/if_dl.h>
#include <net/if_types.h>
#include <net/route.h>

/* IP */
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <arpa/inet.h>
#include <netdb.h>

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "ifconfig.h"

/*
 * This macro returns the size of a struct sockaddr when passed
 * through a routing socket. Basically we round up sa_len to
 * a multiple of sizeof(long), with a minimum of sizeof(long).
 * The check for a NULL pointer is just a convenience, probably never used.
 * The case sa_len == 0 should only apply to empty structures.
 */     
#define SA_SIZE(sa)                                             \
    (  (!(sa) || ((struct sockaddr *)(sa))->sa_len == 0) ?      \
        sizeof(long)            :                               \
        1 + ( (((struct sockaddr *)(sa))->sa_len - 1) | (sizeof(long) - 1) ) )

/*
 * Since "struct ifreq" is composed of various union members, callers
 * should pay special attention to interprete the value.
 * (.e.g. little/big endian difference in the structure.)
 */
struct  ifreq ifr;

char    name[IFNAMSIZ];
int     flags;
int     setaddr;
int     setipdst;
int     setmask;
int     doalias;
int     clearaddr;
int     newaddr = 1;
int     verbose;

int     supmedia = 0;
int     printkeys = 0;          /* Print keying material for interfaces. */
int     printname = 0;          /* Print the name of the created interface. */

static  int ifconfig(int argc, char *const *argv, const struct afswtch *afp);
static  void status(const struct afswtch *afp, int addrcount,
                    struct sockaddr_dl *sdl, struct if_msghdr *ifm,
                    struct ifa_msghdr *ifam);
static  void tunnel_status(int s);
static  void usage(void);

static struct afswtch *af_getbyname(const char *name);
static struct afswtch *af_getbyfamily(int af);
static void af_other_status(int);

static struct option *opts = NULL;

void
opt_register(struct option *p)
{
        p->next = opts;
        opts = p;
}

static void
usage(void)
{
        char options[1024];
        struct option *p;

        /* XXX not right but close enough for now */
        options[0] = '\0';
        for (p = opts; p != NULL; p = p->next) {
                strlcat(options, p->opt_usage, sizeof(options));
                strlcat(options, " ", sizeof(options));
        }

        fprintf(stderr,
        "usage: ifconfig %sinterface address_family [address [dest_address]]\n"
        "                [parameters]\n"
        "       ifconfig interface create\n"
        "       ifconfig -a %s[-d] [-m] [-u] [-v] [address_family]\n"
        "       ifconfig -l [-d] [-u] [address_family]\n"
        "       ifconfig %s[-d] [-m] [-u] [-v]\n",
                options, options, options);
        exit(1);
}

int
main(int argc, char *argv[])
{
        int c, all, namesonly, downonly, uponly;
        int need_nl = 0, count = 0;
        const struct afswtch *afp = NULL;
        int addrcount, ifindex;
        struct if_msghdr *ifm, *nextifm;
        struct ifa_msghdr *ifam;
        struct sockaddr_dl *sdl;
        char *buf, *lim, *next;
        size_t needed;
        int mib[6];
        char options[1024];
        struct option *p;

        all = downonly = uponly = namesonly = verbose = 0;

        /* Parse leading line options */
        strlcpy(options, "adklmuv", sizeof(options));
        for (p = opts; p != NULL; p = p->next)
                strlcat(options, p->opt, sizeof(options));
        while ((c = getopt(argc, argv, options)) != -1) {
                switch (c) {
                case 'a':       /* scan all interfaces */
                        all++;
                        break;
                case 'd':       /* restrict scan to "down" interfaces */
                        downonly++;
                        break;
                case 'k':
                        printkeys++;
                        break;
                case 'l':       /* scan interface names only */
                        namesonly++;
                        break;
                case 'm':       /* show media choices in status */
                        supmedia = 1;
                        break;
                case 'u':       /* restrict scan to "up" interfaces */
                        uponly++;
                        break;
                case 'v':
                        verbose++;
                        break;
                default:
                        for (p = opts; p != NULL; p = p->next)
                                if (p->opt[0] == c) {
                                        p->cb(optarg);
                                        break;
                                }
                        if (p == NULL)
                                usage();
                        break;
                }
        }
        argc -= optind;
        argv += optind;

        /* -l cannot be used with -a or -m */
        if (namesonly && (all || supmedia))
                usage();

        /* nonsense.. */
        if (uponly && downonly)
                usage();

        /* no arguments is equivalent to '-a' */
        if (!namesonly && argc < 1)
                all = 1;

        /* -a and -l allow an address family arg to limit the output */
        if (all || namesonly) {
                if (argc > 1)
                        usage();

                ifindex = 0;
                if (argc == 1) {
                        afp = af_getbyname(*argv);
                        if (afp == NULL)
                                usage();
                        if (afp->af_name != NULL)
                                argc--, argv++;
                        /* leave with afp non-zero */
                }
        } else {
                /* not listing, need an argument */
                if (argc < 1)
                        usage();

                strncpy(name, *argv, sizeof(name));
                argc--, argv++;

                /* check and maybe load support for this interface */
                ifmaybeload(name);

                /*
                 * NOTE:  We must special-case the `create' command right
                 * here as we would otherwise fail when trying to find
                 * the interface.
                 */
                if (argc > 0 && (strcmp(argv[0], "create") == 0 ||
                    strcmp(argv[0], "plumb") == 0)) {
                        clone_create();
                        argc--, argv++;
                        if (argc == 0)
                                goto end;
                }
                ifindex = if_nametoindex(name);
                if (ifindex == 0)
                        errx(1, "interface %s does not exist", name);
        }

        /* Check for address family */
        if (argc > 0) {
                afp = af_getbyname(*argv);
                if (afp != NULL)
                        argc--, argv++;
        }

retry:
        mib[0] = CTL_NET;
        mib[1] = PF_ROUTE;
        mib[2] = 0;
        mib[3] = 0;                     /* address family */
        mib[4] = NET_RT_IFLIST;
        mib[5] = ifindex;               /* interface index */

        /* if particular family specified, only ask about it */
        if (afp != NULL)
                mib[3] = afp->af_af;

        if (sysctl(mib, 6, NULL, &needed, NULL, 0) < 0)
                errx(1, "iflist-sysctl-estimate");
        if ((buf = malloc(needed)) == NULL)
                errx(1, "malloc");
        if (sysctl(mib, 6, buf, &needed, NULL, 0) < 0) {
                if (errno == ENOMEM && count++ < 10) {
                        warnx("Routing table grew, retrying");
                        free(buf);
                        sleep(1);
                        goto retry;
                }
                errx(1, "actual retrieval of interface table");
        }
        lim = buf + needed;

        next = buf;
        while (next < lim) {
                int name_len;

                ifm = (struct if_msghdr *)next;
                
                if (ifm->ifm_type == RTM_IFINFO) {
#ifdef notyet
                        if (ifm->ifm_data.ifi_datalen == 0)
                                ifm->ifm_data.ifi_datalen = sizeof(struct if_data);
                        sdl = (struct sockaddr_dl *)((char *)ifm + sizeof(struct if_msghdr) -
                            sizeof(struct if_data) + ifm->ifm_data.ifi_datalen);
#else
                        sdl = (struct sockaddr_dl *)(ifm + 1);
#endif
                        flags = ifm->ifm_flags;
                } else {
                        fprintf(stderr, "out of sync parsing NET_RT_IFLIST\n");
                        fprintf(stderr, "expected %d, got %d\n", RTM_IFINFO,
                                ifm->ifm_type);
                        fprintf(stderr, "msglen = %d\n", ifm->ifm_msglen);
                        fprintf(stderr, "buf:%p, next:%p, lim:%p\n", buf, next,
                                lim);
                        exit (1);
                }

                next += ifm->ifm_msglen;
                ifam = NULL;
                addrcount = 0;
                while (next < lim) {

                        nextifm = (struct if_msghdr *)next;

                        if (nextifm->ifm_type != RTM_NEWADDR)
                                break;

                        if (ifam == NULL)
                                ifam = (struct ifa_msghdr *)nextifm;

                        addrcount++;
                        next += nextifm->ifm_msglen;
                }

                if (sizeof(name) <= sdl->sdl_nlen)
                        name_len = sizeof(name) - 1;
                else
                        name_len = sdl->sdl_nlen;

                memcpy(name, sdl->sdl_data, name_len);
                name[name_len] = '\0';

                if (all || namesonly) {
                        if (uponly)
                                if ((flags & IFF_UP) == 0)
                                        continue; /* not up */
                        if (downonly)
                                if (flags & IFF_UP)
                                        continue; /* not down */
                        if (namesonly) {
                                if (afp == NULL || afp->af_af != AF_LINK ||
                                    sdl->sdl_type == IFT_ETHER) {
                                        if (need_nl)
                                                putchar(' ');
                                        fputs(name, stdout);
                                        need_nl++;
                                }
                                continue;
                        }
                }

                if (argc > 0)
                        ifconfig(argc, argv, afp);
                else
                        status(afp, addrcount, sdl, ifm, ifam);
        }
        free(buf);

        if (namesonly && need_nl > 0)
                putchar('\n');
end:
        if (printname)
                printf("%s\n", name);

        exit (0);
}

static struct afswtch *afs = NULL;

void
af_register(struct afswtch *p)
{
        p->af_next = afs;
        afs = p;
}

static struct afswtch *
af_getbyname(const char *name)
{
        struct afswtch *afp;

        for (afp = afs; afp !=  NULL; afp = afp->af_next)
                if (strcmp(afp->af_name, name) == 0)
                        return afp;
        return NULL;
}

static struct afswtch *
af_getbyfamily(int af)
{
        struct afswtch *afp;

        for (afp = afs; afp != NULL; afp = afp->af_next)
                if (afp->af_af == af)
                        return afp;
        return NULL;
}

static void
af_other_status(int s)
{
        struct afswtch *afp;
        uint8_t afmask[howmany(AF_MAX, NBBY)];

        memset(afmask, 0, sizeof(afmask));
        for (afp = afs; afp != NULL; afp = afp->af_next) {
                if (afp->af_other_status == NULL)
                        continue;
                if (afp->af_af != AF_UNSPEC && isset(afmask, afp->af_af))
                        continue;
                afp->af_other_status(s);
                setbit(afmask, afp->af_af);
        }
}

static void
af_all_tunnel_status(int s)
{
        struct afswtch *afp;
        uint8_t afmask[howmany(AF_MAX, NBBY)];

        memset(afmask, 0, sizeof(afmask));
        for (afp = afs; afp != NULL; afp = afp->af_next) {
                if (afp->af_status_tunnel == NULL)
                        continue;
                if (afp->af_af != AF_UNSPEC && isset(afmask, afp->af_af))
                        continue;
                afp->af_status_tunnel(s);
                setbit(afmask, afp->af_af);
        }
}

static struct cmd *cmds = NULL;

void
cmd_register(struct cmd *p)
{
        p->c_next = cmds;
        cmds = p;
}

static const struct cmd *
cmd_lookup(const char *name)
{
#define N(a)    (sizeof(a)/sizeof(a[0]))
        const struct cmd *p;

        for (p = cmds; p != NULL; p = p->c_next)
                if (strcmp(name, p->c_name) == 0)
                        return p;
        return NULL;
#undef N
}

struct callback {
        callback_func *cb_func;
        void    *cb_arg;
        struct callback *cb_next;
};
static struct callback *callbacks = NULL;

void
callback_register(callback_func *func, void *arg)
{
        struct callback *cb;

        cb = malloc(sizeof(struct callback));
        if (cb == NULL)
                errx(1, "unable to allocate memory for callback");
        cb->cb_func = func;
        cb->cb_arg = arg;
        cb->cb_next = callbacks;
        callbacks = cb;
}

/* specially-handled commands */
static void setifaddr(const char *, int, int, const struct afswtch *);
static const struct cmd setifaddr_cmd = DEF_CMD("ifaddr", 0, setifaddr);

static void setifdstaddr(const char *, int, int, const struct afswtch *);
static const struct cmd setifdstaddr_cmd =
        DEF_CMD("ifdstaddr", 0, setifdstaddr);

static int
ifconfig(int argc, char *const *argv, const struct afswtch *afp)
{
        struct callback *cb;
        int s;

        if (afp == NULL)
                afp = af_getbyname("inet");
        ifr.ifr_addr.sa_family =
                afp->af_af == AF_LINK || afp->af_af == AF_UNSPEC ?
                AF_INET : afp->af_af;
        strncpy(ifr.ifr_name, name, sizeof ifr.ifr_name);

        if ((s = socket(ifr.ifr_addr.sa_family, SOCK_DGRAM, 0)) < 0)
                err(1, "socket(family %u,SOCK_DGRAM", ifr.ifr_addr.sa_family);

        while (argc > 0) {
                const struct cmd *p;

                p = cmd_lookup(*argv);
                if (p == NULL) {
                        /*
                         * Not a recognized command, choose between setting
                         * the interface address and the dst address.
                         */
                        p = (setaddr ? &setifdstaddr_cmd : &setifaddr_cmd);
                }
                if (p->c_u.c_func || p->c_u.c_func2) {
                        if (p->c_parameter == NEXTARG) {
                                if (argv[1] == NULL)
                                        errx(1, "'%s' requires argument",
                                            p->c_name);
                                p->c_u.c_func(argv[1], 0, s, afp);
                                argc--, argv++;
                        } else if (p->c_parameter == OPTARG) {
                                p->c_u.c_func(argv[1], 0, s, afp);
                                if (argv[1] != NULL)
                                        argc--, argv++;
                        } else if (p->c_parameter == NEXTARG2) {
                                if (argc < 3)
                                        errx(1, "'%s' requires 2 arguments",
                                            p->c_name);
                                p->c_u.c_func2(argv[1], argv[2], s, afp);
                                argc -= 2, argv += 2;
                        } else
                                p->c_u.c_func(*argv, p->c_parameter, s, afp);
                }
                argc--, argv++;
        }

        /*
         * Do any post argument processing required by the address family.
         */
        if (afp->af_postproc != NULL)
                afp->af_postproc(s, afp);
        /*
         * Do deferred callbacks registered while processing
         * command-line arguments.
         */
        for (cb = callbacks; cb != NULL; cb = cb->cb_next)
                cb->cb_func(s, cb->cb_arg);
        /*
         * Do deferred operations.
         */
        if (clearaddr) {
                if (afp->af_ridreq == NULL || afp->af_difaddr == 0) {
                        warnx("interface %s cannot change %s addresses!",
                              name, afp->af_name);
                        clearaddr = 0;
                }
        }
        if (clearaddr) {
                int ret;
                strncpy(afp->af_ridreq, name, sizeof ifr.ifr_name);
                ret = ioctl(s, afp->af_difaddr, afp->af_ridreq);
                if (ret < 0) {
                        if (errno == EADDRNOTAVAIL && (doalias >= 0)) {
                                /* means no previous address for interface */
                        } else
                                Perror("ioctl (SIOCDIFADDR)");
                }
        }
        if (newaddr) {
                if (afp->af_addreq == NULL || afp->af_aifaddr == 0) {
                        warnx("interface %s cannot change %s addresses!",
                              name, afp->af_name);
                        newaddr = 0;
                }
        }
        if (newaddr && (setaddr || setmask)) {
                strncpy(afp->af_addreq, name, sizeof ifr.ifr_name);
                if (ioctl(s, afp->af_aifaddr, afp->af_addreq) < 0)
                        Perror("ioctl (SIOCAIFADDR)");
        }

        close(s);
        return(0);
}

/*ARGSUSED*/
static void
setifaddr(const char *addr, int param, int s, const struct afswtch *afp)
{
        if (afp->af_getaddr == NULL)
                return;
        /*
         * Delay the ioctl to set the interface addr until flags are all set.
         * The address interpretation may depend on the flags,
         * and the flags may change when the address is set.
         */
        setaddr++;
        if (doalias == 0 && afp->af_af != AF_LINK)
                clearaddr = 1;
        afp->af_getaddr(addr, (doalias >= 0 ? ADDR : RIDADDR));
}

static void
settunnel(const char *src, const char *dst, int s, const struct afswtch *afp)
{
        struct addrinfo *srcres, *dstres;
        int ecode;

        if (afp->af_settunnel == NULL) {
                warn("address family %s does not support tunnel setup",
                        afp->af_name);
                return;
        }

        if ((ecode = getaddrinfo(src, NULL, NULL, &srcres)) != 0)
                errx(1, "error in parsing address string: %s",
                    gai_strerror(ecode));

        if ((ecode = getaddrinfo(dst, NULL, NULL, &dstres)) != 0)  
                errx(1, "error in parsing address string: %s",
                    gai_strerror(ecode));

        if (srcres->ai_addr->sa_family != dstres->ai_addr->sa_family)
                errx(1,
                    "source and destination address families do not match");

        afp->af_settunnel(s, srcres, dstres);

        freeaddrinfo(srcres);
        freeaddrinfo(dstres);
}

/* ARGSUSED */
static void
deletetunnel(const char *vname, int param, int s, const struct afswtch *afp)
{

        if (ioctl(s, SIOCDIFPHYADDR, &ifr) < 0)
                err(1, "SIOCDIFPHYADDR");
}

static void
setifnetmask(const char *addr, int dummy __unused, int s,
    const struct afswtch *afp)
{
        if (afp->af_getaddr != NULL) {
                setmask++;
                afp->af_getaddr(addr, MASK);
        }
}

static void
setifbroadaddr(const char *addr, int dummy __unused, int s,
    const struct afswtch *afp)
{
        if (afp->af_getaddr != NULL)
                afp->af_getaddr(addr, DSTADDR);
}

static void
setifipdst(const char *addr, int dummy __unused, int s,
    const struct afswtch *afp)
{
        const struct afswtch *inet;

        inet = af_getbyname("inet");
        if (inet == NULL)
                return;
        inet->af_getaddr(addr, DSTADDR);
        setipdst++;
        clearaddr = 0;
        newaddr = 0;
}

static void
notealias(const char *addr, int param, int s, const struct afswtch *afp)
{
#define rqtosa(x) (&(((struct ifreq *)(afp->x))->ifr_addr))
        if (setaddr && doalias == 0 && param < 0)
                if (afp->af_addreq != NULL && afp->af_ridreq != NULL)
                        bcopy((caddr_t)rqtosa(af_addreq),
                              (caddr_t)rqtosa(af_ridreq),
                              rqtosa(af_addreq)->sa_len);
        doalias = param;
        if (param < 0) {
                clearaddr = 1;
                newaddr = 0;
        } else
                clearaddr = 0;
#undef rqtosa
}

/*ARGSUSED*/
static void
setifdstaddr(const char *addr, int param __unused, int s, 
    const struct afswtch *afp)
{
        if (afp->af_getaddr != NULL)
                afp->af_getaddr(addr, DSTADDR);
}

/*
 * Note: doing an SIOCIGIFFLAGS scribbles on the union portion
 * of the ifreq structure, which may confuse other parts of ifconfig.
 * Make a private copy so we can avoid that.
 */
static void
setifflags(const char *vname, int value, int s, const struct afswtch *afp)
{
        struct ifreq            my_ifr;

        bcopy((char *)&ifr, (char *)&my_ifr, sizeof(struct ifreq));

        if (ioctl(s, SIOCGIFFLAGS, (caddr_t)&my_ifr) < 0) {
                Perror("ioctl (SIOCGIFFLAGS)");
                exit(1);
        }
        strncpy(my_ifr.ifr_name, name, sizeof (my_ifr.ifr_name));
        flags = (my_ifr.ifr_flags & 0xffff) | (my_ifr.ifr_flagshigh << 16);

        if (value < 0) {
                value = -value;
                flags &= ~value;
        } else
                flags |= value;
        my_ifr.ifr_flags = flags & 0xffff;
        my_ifr.ifr_flagshigh = flags >> 16;
        if (ioctl(s, SIOCSIFFLAGS, (caddr_t)&my_ifr) < 0)
                Perror(vname);
}

void
setifcap(const char *vname, int value, int s, const struct afswtch *afp)
{

        if (ioctl(s, SIOCGIFCAP, (caddr_t)&ifr) < 0) {
                Perror("ioctl (SIOCGIFCAP)");
                exit(1);
        }
        flags = ifr.ifr_curcap;
        if (value < 0) {
                value = -value;
                flags &= ~value;
        } else
                flags |= value;
        ifr.ifr_reqcap = flags;
        if (ioctl(s, SIOCSIFCAP, (caddr_t)&ifr) < 0)
                Perror(vname);
}

static void
setifmetric(const char *val, int dummy __unused, int s, 
    const struct afswtch *afp)
{
        strncpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
        ifr.ifr_metric = atoi(val);
        if (ioctl(s, SIOCSIFMETRIC, (caddr_t)&ifr) < 0)
                warn("ioctl (set metric)");
}

static void
setifmtu(const char *val, int dummy __unused, int s, 
    const struct afswtch *afp)
{
        strncpy(ifr.ifr_name, name, sizeof (ifr.ifr_name));
        ifr.ifr_mtu = atoi(val);
        if (ioctl(s, SIOCSIFMTU, (caddr_t)&ifr) < 0)
                warn("ioctl (set mtu)");
}

static void
setifname(const char *val, int dummy __unused, int s, 
    const struct afswtch *afp)
{
        char *newname;

        newname = strdup(val);
        if (newname == NULL) {
                warn("no memory to set ifname");
                return;
        }
        ifr.ifr_data = newname;
        if (ioctl(s, SIOCSIFNAME, (caddr_t)&ifr) < 0) {
                warn("ioctl (set name)");
                free(newname);
                return;
        }
        strlcpy(name, newname, sizeof(name));
        free(newname);

        /*
         * Even if we just created the interface, we don't need to print
         * its name because we just nailed it down separately.
         */
        printname = 0;
}

static void
setifpollcpu(const char *val, int dummy __unused, int s, 
    const struct afswtch *afp)
{
        int pollcpu;

        pollcpu = atoi(val);
        if (pollcpu < 0) {
                warn("pollcpu < 0");
                return;
        }

        setifflags("-polling", -IFF_POLLING, s, afp);

        ifr.ifr_pollcpu = pollcpu;
        if (ioctl(s, SIOCSIFPOLLCPU, (caddr_t)&ifr) < 0) {
                warn("ioctl (set pollcpu)");
                return;
        }
}

/*
 * Expand the compacted form of addresses as returned via the
 * configuration read via sysctl().
 */
static void
rt_xaddrs(caddr_t cp, caddr_t cplim, struct rt_addrinfo *rtinfo)
{
        struct sockaddr *sa;
        int i;

        memset(rtinfo->rti_info, 0, sizeof(rtinfo->rti_info));
        for (i = 0; (i < RTAX_MAX) && (cp < cplim); i++) {
                if ((rtinfo->rti_addrs & (1 << i)) == 0)
                        continue;
                rtinfo->rti_info[i] = sa = (struct sockaddr *)cp;
                cp += SA_SIZE(sa);
        }
}

#define IFFBITS \
"\020\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5POINTOPOINT\6SMART\7RUNNING" \
"\10NOARP\11PROMISC\12ALLMULTI\13OACTIVE\14SIMPLEX\15LINK0\16LINK1\17LINK2" \
"\20MULTICAST\21POLLING\22PPROMISC\23MONITOR\24STATICARP\25NEEDSGIANT"

#define IFCAPBITS \
"\020\1RXCSUM\2TXCSUM\3NETCONS\4VLAN_MTU\5VLAN_HWTAGGING\6JUMBO_MTU\7POLLING"

/*
 * Print the status of the interface.  If an address family was
 * specified, show only it; otherwise, show them all.
 */
static void
status(const struct afswtch *afp, int addrcount, struct sockaddr_dl *sdl,
    struct if_msghdr *ifm, struct ifa_msghdr *ifam)
{
        struct  rt_addrinfo info;
        int allfamilies, s;
        struct ifstat ifs;

        if (afp == NULL) {
                allfamilies = 1;
                afp = af_getbyname("inet");
        } else
                allfamilies = 0;

        ifr.ifr_addr.sa_family = afp->af_af == AF_LINK ? AF_INET : afp->af_af;
        strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));

        s = socket(ifr.ifr_addr.sa_family, SOCK_DGRAM, 0);
        if (s < 0)
                err(1, "socket(family %u,SOCK_DGRAM)", ifr.ifr_addr.sa_family);

        printf("%s: ", name);
        printb("flags", flags, IFFBITS);
        if (ifm->ifm_data.ifi_metric)
                printf(" metric %ld", ifm->ifm_data.ifi_metric);
        if (ifm->ifm_data.ifi_mtu)
                printf(" mtu %ld", ifm->ifm_data.ifi_mtu);
        putchar('\n');

        if (ioctl(s, SIOCGIFCAP, (caddr_t)&ifr) == 0) {
                if (ifr.ifr_curcap != 0) {
                        printb("\toptions", ifr.ifr_curcap, IFCAPBITS);
                        putchar('\n');
                }
                if (supmedia && ifr.ifr_reqcap != 0) {
                        printb("\tcapabilities", ifr.ifr_reqcap, IFCAPBITS);
                        putchar('\n');
                }
        }

        tunnel_status(s);

        while (addrcount > 0) {
                info.rti_addrs = ifam->ifam_addrs;
                /* Expand the compacted addresses */
                rt_xaddrs((char *)(ifam + 1), ifam->ifam_msglen + (char *)ifam,
                          &info);

                if (allfamilies) {
                        const struct afswtch *p;
                        p = af_getbyfamily(info.rti_info[RTAX_IFA]->sa_family);
                        if (p != NULL && p->af_status != NULL)
                                p->af_status(s, &info);
                } else if (afp->af_af == info.rti_info[RTAX_IFA]->sa_family)
                        afp->af_status(s, &info);
                addrcount--;
                ifam = (struct ifa_msghdr *)((char *)ifam + ifam->ifam_msglen);
        }
        if (allfamilies || afp->af_af == AF_LINK) {
                const struct afswtch *lafp;

                /*
                 * Hack; the link level address is received separately
                 * from the routing information so any address is not
                 * handled above.  Cobble together an entry and invoke
                 * the status method specially.
                 */
                lafp = af_getbyname("lladdr");
                if (lafp != NULL) {
                        info.rti_info[RTAX_IFA] = (struct sockaddr *)sdl;
                        lafp->af_status(s, &info);
                }
        }
        if (allfamilies)
                af_other_status(s);
        else if (afp->af_other_status != NULL)
                afp->af_other_status(s);

        strncpy(ifs.ifs_name, name, sizeof ifs.ifs_name);
        if (ioctl(s, SIOCGIFSTATUS, &ifs) == 0) 
                printf("%s", ifs.ascii);

        if (flags & IFF_POLLING) {
                if (ioctl(s, SIOCGIFPOLLCPU, &ifr) == 0 && ifr.ifr_pollcpu >= 0)
                        printf("\tpollcpu: %d\n", ifr.ifr_pollcpu);
        }

        close(s);
        return;
}

static void
tunnel_status(int s)
{
        af_all_tunnel_status(s);
}

void
Perror(const char *cmd)
{
        switch (errno) {

        case ENXIO:
                errx(1, "%s: no such interface", cmd);
                break;

        case EPERM:
                errx(1, "%s: permission denied", cmd);
                break;

        default:
                err(1, "%s", cmd);
        }
}

/*
 * Print a value a la the %b format of the kernel's printf
 */
void
printb(const char *s, unsigned v, const char *bits)
{
        int i, any = 0;
        char c;

        if (bits && *bits == 8)
                printf("%s=%o", s, v);
        else
                printf("%s=%x", s, v);
        bits++;
        if (bits) {
                putchar('<');
                while ((i = *bits++) != '\0') {
                        if (v & (1 << (i-1))) {
                                if (any)
                                        putchar(',');
                                any = 1;
                                for (; (c = *bits) > 32; bits++)
                                        putchar(c);
                        } else
                                for (; *bits > 32; bits++)
                                        ;
                }
                putchar('>');
        }
}

void
ifmaybeload(char *name)
{
        struct module_stat mstat;
        int fileid, modid;
        char ifkind[35], *cp, *dp;

        /* turn interface and unit into module name */
        strcpy(ifkind, "if_");
        for (cp = name, dp = ifkind + 3;
            (*cp != 0) && !isdigit(*cp); cp++, dp++)
                *dp = *cp;
        *dp = 0;

        /* scan files in kernel */
        mstat.version = sizeof(struct module_stat);
        for (fileid = kldnext(0); fileid > 0; fileid = kldnext(fileid)) {
                /* scan modules in file */
                for (modid = kldfirstmod(fileid); modid > 0;
                     modid = modfnext(modid)) {
                        if (modstat(modid, &mstat) < 0)
                                continue;
                        /* strip bus name if present */
                        if ((cp = strchr(mstat.name, '/')) != NULL) {
                                cp++;
                        } else {
                                cp = mstat.name;
                        }
                        /* already loaded? */
                        if (strncmp(name, cp, strlen(cp)) == 0 ||
                            strncmp(ifkind, cp, strlen(cp)) == 0)
                                return;
                }
        }

        /* not present, we should try to load it */
        kldload(ifkind);
}

static struct cmd basic_cmds[] = {
        DEF_CMD("up",           IFF_UP,         setifflags),
        DEF_CMD("down",         -IFF_UP,        setifflags),
        DEF_CMD("arp",          -IFF_NOARP,     setifflags),
        DEF_CMD("-arp",         IFF_NOARP,      setifflags),
        DEF_CMD("debug",        IFF_DEBUG,      setifflags),
        DEF_CMD("-debug",       -IFF_DEBUG,     setifflags),
        DEF_CMD("promisc",      IFF_PPROMISC,   setifflags),
        DEF_CMD("-promisc",     -IFF_PPROMISC,  setifflags),
        DEF_CMD("add",          IFF_UP,         notealias),
        DEF_CMD("alias",        IFF_UP,         notealias),
        DEF_CMD("-alias",       -IFF_UP,        notealias),
        DEF_CMD("delete",       -IFF_UP,        notealias),
        DEF_CMD("remove",       -IFF_UP,        notealias),
#ifdef notdef
#define EN_SWABIPS      0x1000
        DEF_CMD("swabips",      EN_SWABIPS,     setifflags),
        DEF_CMD("-swabips",     -EN_SWABIPS,    setifflags),
#endif
        DEF_CMD_ARG("netmask",                  setifnetmask),
        DEF_CMD_ARG("metric",                   setifmetric),
        DEF_CMD_ARG("broadcast",                setifbroadaddr),
#ifndef NO_IPX
        DEF_CMD_ARG("ipdst",                    setifipdst),
#endif
        DEF_CMD_ARG2("tunnel",                  settunnel),
        DEF_CMD("-tunnel", 0,                   deletetunnel),
        DEF_CMD("deletetunnel", 0,              deletetunnel),
        DEF_CMD("link0",        IFF_LINK0,      setifflags),
        DEF_CMD("-link0",       -IFF_LINK0,     setifflags),
        DEF_CMD("link1",        IFF_LINK1,      setifflags),
        DEF_CMD("-link1",       -IFF_LINK1,     setifflags),
        DEF_CMD("link2",        IFF_LINK2,      setifflags),
        DEF_CMD("-link2",       -IFF_LINK2,     setifflags),
        DEF_CMD("monitor",      IFF_MONITOR,    setifflags),
        DEF_CMD("-monitor",     -IFF_MONITOR,   setifflags),
#ifdef notyet
        DEF_CMD("staticarp",    IFF_STATICARP,  setifflags),
        DEF_CMD("-staticarp",   -IFF_STATICARP, setifflags),
#endif
        DEF_CMD("polling",      IFF_POLLING,    setifflags),
        DEF_CMD("-polling",     -IFF_POLLING,   setifflags),
        DEF_CMD("rxcsum",       IFCAP_RXCSUM,   setifcap),
        DEF_CMD("-rxcsum",      -IFCAP_RXCSUM,  setifcap),
        DEF_CMD("txcsum",       IFCAP_TXCSUM,   setifcap),
        DEF_CMD("-txcsum",      -IFCAP_TXCSUM,  setifcap),
        DEF_CMD("netcons",      IFCAP_NETCONS,  setifcap),
        DEF_CMD("-netcons",     -IFCAP_NETCONS, setifcap),
        DEF_CMD("normal",       -IFF_LINK0,     setifflags),
        DEF_CMD("compress",     IFF_LINK0,      setifflags),
        DEF_CMD("noicmp",       IFF_LINK1,      setifflags),
        DEF_CMD_ARG("mtu",                      setifmtu),
        DEF_CMD_ARG("name",                     setifname),
        DEF_CMD_ARG("pollcpu",                  setifpollcpu)
};

static __constructor void
ifconfig_ctor(void)
{
#define N(a)    (sizeof(a) / sizeof(a[0]))
        int i;

        for (i = 0; i < N(basic_cmds);  i++)
                cmd_register(&basic_cmds[i]);
#undef N
}