/*
 * 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.
 * 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.
 *
 * $FreeBSD: src/sbin/ifconfig/ifconfig.c,v 1.113.2.4 2006/02/09 10:48:43 yar 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 <sys/cdefs.h>
#include <sys/queue.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 <fnmatch.h>
#include <ifaddrs.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "ifconfig.h"

/* Globals */
char    IfName[IFNAMSIZ];       /* name of interface */
bool    newaddr = true;
bool    verbose;
bool    supmedia = false;
bool    printkeys = false;      /* Print keying material for interfaces. */
bool    printifname = false;    /* Print the name of the created interface. */
int     exit_code = 0;
char    *f_inet, *f_inet6, *f_ether, *f_addr;   /* Formatter strings */

static  bool group_member(const char *ifname, const char *match,
                          const char *nomatch);
static  int ifconfig(int argc, char *const *argv, int iscreate,
                     const struct afswtch *afp);
static  void status(const struct afswtch *afp, const struct sockaddr_dl *sdl,
                    struct ifaddrs *ifa);
static  void tunnel_status(int s);
static  void usage(void) __dead2;

static int getifflags(const char *ifname, int us);
static struct afswtch *af_getbyname(const char *name);
static struct afswtch *af_getbyfamily(int af);
static void af_other_status(int);
static void printifnamemaybe(void);
static void freeformat(void);
static void setformat(char *input);

static struct option *opts = NULL;
static char *descr = NULL;
static size_t descrlen = 64;
static bool clearaddr;
static int doalias;
static bool noload;
static bool setaddr;
static bool setmask;

struct ifa_order_elt {
        int             if_order;
        int             af_orders[255];
        struct ifaddrs  *ifa;
        TAILQ_ENTRY(ifa_order_elt) link;
};
TAILQ_HEAD(ifa_queue, ifa_order_elt);

static int calcorders(struct ifaddrs *ifa, struct ifa_queue *q);
static int cmpifaddrs(struct ifaddrs *a, struct ifaddrs *b,
                      struct ifa_queue *q);
typedef int (*ifaddrs_cmp)(struct ifaddrs *, struct ifaddrs *, struct ifa_queue *);
static struct ifaddrs *sortifaddrs(struct ifaddrs *list, ifaddrs_cmp compare,
                                   struct ifa_queue *q);


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 %s[-n] [-f type:format] interface address_family\n"
        "                [address [dest_address]] [parameters]\n"
        "       ifconfig [-n] interface create\n"
        "       ifconfig [-n] interface destroy\n"
        "       ifconfig -a %s[-G nogroup] [-d | -u] [-m] [-v] [address_family]\n"
        "       ifconfig -l [-d | -u] [address_family]\n"
        "       ifconfig %s[-d | -u] [-m] [-v]\n",
                options, options, options);
        exit(1);
}

static int
calcorders(struct ifaddrs *ifa, struct ifa_queue *q)
{
        struct ifaddrs *prev;
        struct ifa_order_elt *cur;
        unsigned int ord, af, ifa_ord;

        prev = NULL;
        cur = NULL;
        ord = 0;
        ifa_ord = 0;

        while (ifa != NULL) {
                if (prev == NULL ||
                    strcmp(ifa->ifa_name, prev->ifa_name) != 0) {
                        cur = calloc(1, sizeof(*cur));
                        if (cur == NULL)
                                return (-1);

                        TAILQ_INSERT_TAIL(q, cur, link);
                        cur->if_order = ifa_ord++;
                        cur->ifa = ifa;
                        ord = 0;
                }

                if (ifa->ifa_addr) {
                        af = ifa->ifa_addr->sa_family;
                        if (af < nitems(cur->af_orders) &&
                            cur->af_orders[af] == 0)
                                cur->af_orders[af] = ++ord;
                }

                prev = ifa;
                ifa = ifa->ifa_next;
        }

        return (0);
}

static int
cmpifaddrs(struct ifaddrs *a, struct ifaddrs *b, struct ifa_queue *q)
{
        struct ifa_order_elt *cur, *e1, *e2;
        unsigned int af1, af2;

        e1 = e2 = NULL;

        if (strcmp(a->ifa_name, b->ifa_name) != 0) {
                TAILQ_FOREACH(cur, q, link) {
                        if (e1 != NULL && e2 != NULL)
                                break;

                        if (strcmp(cur->ifa->ifa_name, a->ifa_name) == 0)
                                e1 = cur;
                        else if (strcmp(cur->ifa->ifa_name, b->ifa_name) == 0)
                                e2 = cur;
                }

                if (e1 == NULL || e2 == NULL)
                        return (0);
                else
                        return (e1->if_order - e2->if_order);

        } else if (a->ifa_addr != NULL && b->ifa_addr != NULL) {
                TAILQ_FOREACH(cur, q, link) {
                        if (strcmp(cur->ifa->ifa_name, a->ifa_name) == 0) {
                                e1 = cur;
                                break;
                        }
                }

                if (e1 == NULL)
                        return (0);

                af1 = a->ifa_addr->sa_family;
                af2 = b->ifa_addr->sa_family;

                if (af1 < nitems(e1->af_orders) && af2 < nitems(e1->af_orders))
                        return (e1->af_orders[af1] - e1->af_orders[af2]);
        }

        return (0);
}

static struct ifaddrs *
sortifaddrs(struct ifaddrs *list, ifaddrs_cmp compare, struct ifa_queue *q)
{
        struct ifaddrs *right, *temp, *last, *result, *next, *tail;

        right = temp = last = list;
        result = next = tail = NULL;

        if (list == NULL || list->ifa_next == NULL)
                return (list);

        while (temp != NULL && temp->ifa_next != NULL) {
                last = right;
                right = right->ifa_next;
                temp = temp->ifa_next->ifa_next;
        }

        last->ifa_next = NULL;

        list = sortifaddrs(list, compare, q);
        right = sortifaddrs(right, compare, q);

        while (list != NULL || right != NULL) {
                if (right == NULL) {
                        next = list;
                        list = list->ifa_next;
                } else if (list == NULL) {
                        next = right;
                        right = right->ifa_next;
                } else if (compare(list, right, q) <= 0) {
                        next = list;
                        list = list->ifa_next;
                } else {
                        next = right;
                        right = right->ifa_next;
                }

                if (result == NULL)
                        result = next;
                else
                        tail->ifa_next = next;

                tail = next;
        }

        return (result);
}

static void
printifnamemaybe(void)
{
        if (printifname)
                printf("%s\n", IfName);
}

static void
freeformat(void)
{
        if (f_inet != NULL)
                free(f_inet);
        if (f_inet6 != NULL)
                free(f_inet6);
        if (f_ether != NULL)
                free(f_ether);
        if (f_addr != NULL)
                free(f_addr);
}

static void
setformat(char *input)
{
        char *formatstr, *category, *modifier;
        char **fp;

        formatstr = strdup(input);
        if (formatstr == NULL)
                err(1, "no memory to set format");

        while ((category = strsep(&formatstr, ",")) != NULL) {
                modifier = strchr(category, ':');
                if (modifier == NULL || modifier[1] == '\0') {
                        warnx("skip invalid format specification: %s\n",
                              category);
                        continue;
                }

                modifier[0] = '\0';
                modifier++;

                fp = NULL;
                if (strcmp(category, "addr") == 0)
                        fp = &f_addr;
                else if (strcmp(category, "ether") == 0)
                        fp = &f_ether;
                else if (strcmp(category, "inet") == 0)
                        fp = &f_inet;
                else if (strcmp(category, "inet6") == 0)
                        fp = &f_inet6;

                if (fp != NULL) {
                        *fp = strdup(modifier);
                        if (*fp == NULL)
                                err(1, "strdup");
                }
        }

        free(formatstr);
}


int
main(int argc, char *argv[])
{
        int c, ifindex, flags;
        bool all, namesonly, downonly, uponly;
        const struct afswtch *afp = NULL;
        const struct sockaddr_dl *sdl;
        const char *ifname, *matchgroup, *nogroup;
        struct ifa_order_elt *cur, *tmp;
        struct ifa_queue q = TAILQ_HEAD_INITIALIZER(q);
        struct ifaddrs *ifap, *sifap, *ifa;
        struct ifreq ifr;
        struct option *p;
        size_t iflen;
        char *envformat, *cp;
        char options[1024];

        doalias = 0;
        all = downonly = uponly = namesonly = verbose = false;
        clearaddr = noload = setaddr = setmask = false;
        f_inet = f_inet6 = f_ether = f_addr = NULL;
        matchgroup = nogroup = NULL;

        /*
         * Ensure we print interface name when expected to,
         * even if we terminate early due to error.
         */
        atexit(printifnamemaybe);

        envformat = getenv("IFCONFIG_FORMAT");
        if (envformat != NULL)
                setformat(envformat);

        /* Parse leading line options */
        strlcpy(options, "adf:G:klmnuv", 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 = true;
                        break;
                case 'd':       /* restrict scan to "down" interfaces */
                        downonly = true;
                        break;
                case 'f':
                        setformat(optarg);
                        break;
                case 'G':
                        if (!all)
                                usage();
                        nogroup = optarg;
                        break;
                case 'k':
                        printkeys = true;
                        break;
                case 'l':       /* scan interface names only */
                        namesonly = true;
                        break;
                case 'm':       /* show media choices in status */
                        supmedia = true;
                        break;
                case 'n':       /* suppress module loading */
                        noload = true;
                        break;
                case 'u':       /* restrict scan to "up" interfaces */
                        uponly = true;
                        break;
                case 'v':
                        verbose = true;
                        break;
                case 'g':
                        if (all) {
                                matchgroup = optarg;
                                break;
                        }
                        /* FALLTHROUGH */
                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();

                ifname = NULL;
                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();

                ifname = *argv;
                argc--, argv++;

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

                ifindex = if_nametoindex(ifname);
                if (ifindex == 0) {
                        /*
                         * 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)) {
                                iflen = strlcpy(IfName, ifname, sizeof(IfName));
                                if (iflen >= sizeof(IfName))
                                        errx(1, "%s: cloning name too long",
                                            ifname);
                                ifconfig(argc, argv, 1, NULL);
                                exit(exit_code);
                        }
                        errx(1, "interface %s does not exist", ifname);
                } else {
                        /*
                         * Do not allow to use `create` command as hostname
                         * if address family is not specified.
                         */
                        if (argc > 0 && (strcmp(argv[0], "create") == 0 ||
                            strcmp(argv[0], "plumb") == 0)) {
                                if (argc == 1)
                                        errx(1, "interface %s already exists",
                                            ifname);
                                argc--, argv++;
                        }
                }
        }

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

        /*
         * Check for a requested configuration action on a single interface,
         * which doesn't require building, sorting, and searching the entire
         * system address list.
         */
        if (argc > 0 && ifname != NULL) {
                iflen = strlcpy(IfName, ifname, sizeof(IfName));
                if (iflen >= sizeof(IfName))
                        errx(1, "%s: cloning name too long", ifname);

                flags = getifflags(IfName, -1);
                if (!((downonly && (flags & IFF_UP) != 0) ||
                      (uponly && (flags & IFF_UP) == 0))) {
                        ifconfig(argc, argv, 0, afp);
                }

                exit(exit_code);
        }

        if (getifaddrs(&ifap) != 0)
                err(1, "getifaddrs");
        if (calcorders(ifap, &q) != 0)
                err(1, "calcorders");
        sifap = sortifaddrs(ifap, cmpifaddrs, &q);

        TAILQ_FOREACH_MUTABLE(cur, &q, link, tmp)
                free(cur);

        cp = NULL;
        ifindex = 0;
        for (ifa = sifap; ifa != NULL; ifa = ifa->ifa_next) {
                memset(&ifr, 0, sizeof(ifr));
                strlcpy(ifr.ifr_name, ifa->ifa_name, sizeof(ifr.ifr_name));
                if (sizeof(ifr.ifr_addr) >= ifa->ifa_addr->sa_len) {
                        memcpy(&ifr.ifr_addr, ifa->ifa_addr,
                               ifa->ifa_addr->sa_len);
                }

                if (ifname != NULL && strcmp(ifname, ifa->ifa_name) != 0)
                        continue;
                if (cp != NULL && strcmp(cp, ifa->ifa_name) == 0)
                        continue;
                iflen = strlcpy(IfName, ifa->ifa_name, sizeof(IfName));
                if (iflen >= sizeof(IfName)) {
                        warnx("%s: interface name too long, skipping",
                              ifa->ifa_name);
                        continue;
                }
                cp = ifa->ifa_name;

                if (downonly && (ifa->ifa_flags & IFF_UP) != 0)
                        continue;
                if (uponly && (ifa->ifa_flags & IFF_UP) == 0)
                        continue;
                if (!group_member(ifa->ifa_name, matchgroup, nogroup))
                        continue;

                if (ifa->ifa_addr->sa_family == AF_LINK)
                        sdl = (const struct sockaddr_dl *)ifa->ifa_addr;
                else
                        sdl = NULL;

                /* Are we just listing the interfaces? */
                if (namesonly) {
                        if (afp == NULL ||
                            afp->af_af != AF_LINK ||
                            (sdl != NULL && sdl->sdl_type == IFT_ETHER)) {
                                printf("%s%s", (ifindex > 0 ? " " : ""),
                                       IfName);
                                ifindex++;
                        }
                        continue;
                }

                if (argc > 0)
                        ifconfig(argc, argv, 0, afp);
                else
                        status(afp, sdl, ifa);
        }

        if (namesonly)
                putchar('\n');

        freeifaddrs(ifap);
        freeformat();

        return (exit_code);
}


/*
 * Returns true if an interface should be listed because any its groups
 * matches shell pattern "match" and none of groups matches pattern "nomatch".
 * If any pattern is NULL, corresponding condition is skipped.
 */
static bool
group_member(const char *ifname, const char *match, const char *nomatch)
{
        static int               sock = -1;

        struct ifgroupreq        ifgr;
        struct ifg_req          *ifg;
        size_t                   len;
        bool                     matched, nomatched;

        /* Sanity checks. */
        if (match == NULL && nomatch == NULL)
                return (true);
        if (ifname == NULL)
                return (false);

        memset(&ifgr, 0, sizeof(ifgr));
        strlcpy(ifgr.ifgr_name, ifname, sizeof(ifgr.ifgr_name));

        /* The socket is opened once. Let _exit() close it. */
        if (sock == -1) {
                sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
                if (sock == -1)
                        errx(1, "%s: socket(AF_LOCAL,SOCK_DGRAM)", __func__);
        }

        /* Determine amount of memory for the list of groups. */
        if (ioctl(sock, SIOCGIFGROUP, &ifgr) == -1) {
                if (errno == EINVAL || errno == ENOTTY)
                        return (false);
                else
                        errx(1, "%s: SIOCGIFGROUP", __func__);
        }

        /* Obtain the list of groups. */
        len = ifgr.ifgr_len;
        ifgr.ifgr_groups = calloc(1, len);
        if (ifgr.ifgr_groups == NULL)
                errx(1, "%s: no memory", __func__);
        if (ioctl(sock, SIOCGIFGROUP, &ifgr) == -1)
                errx(1, "%s: SIOCGIFGROUP", __func__);

        /* Perform matching. */
        matched = false;
        nomatched = true;
        for (ifg = ifgr.ifgr_groups; ifg && len >= sizeof(*ifg); ifg++) {
                len -= sizeof(struct ifg_req);
                if (match)
                        matched |= !fnmatch(match, ifg->ifgrq_group, 0);
                if (nomatch)
                        nomatched &= fnmatch(nomatch, ifg->ifgrq_group, 0);
        }

        if (match && !nomatch)
                return (matched);
        if (!match && nomatch)
                return (nomatched);
        return (matched && nomatched);
}


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, int iscreate)
{
        const struct cmd *p;

        for (p = cmds; p != NULL; p = p->c_next) {
                if (strcmp(name, p->c_name) == 0) {
                        if (iscreate) {
                                if (p->c_iscloneop)
                                        return p;
                        } else {
                                if (!p->c_iscloneop)
                                        return p;
                        }
                }
        }

        return NULL;
}

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, int iscreate,
         const struct afswtch *uafp)
{
        const struct afswtch *afp, *nafp;
        const struct cmd *p;
        struct ifreq ifr;
        struct callback *cb;
        int s;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));
        afp = uafp != NULL ? uafp : af_getbyname("inet");
top:
        ifr.ifr_addr.sa_family =
                afp->af_af == AF_LINK || afp->af_af == AF_UNSPEC ?
                AF_LOCAL : afp->af_af;

        if ((s = socket(ifr.ifr_addr.sa_family, SOCK_DGRAM, 0)) < 0 &&
            (uafp != NULL || errno != EAFNOSUPPORT ||
             (s = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0))
                err(1, "socket(family %u,SOCK_DGRAM)", ifr.ifr_addr.sa_family);

        while (argc > 0) {
                p = cmd_lookup(*argv, iscreate);
                if (iscreate && p == NULL) {
                        /*
                         * Push the clone create callback so the new
                         * device is created and can be used for any
                         * remaining arguments.
                         */
                        cb = callbacks;
                        if (cb == NULL)
                                errx(1, "internal error, no callback");
                        callbacks = cb->cb_next;
                        cb->cb_func(s, cb->cb_arg);
                        iscreate = 0;

                        /*
                         * Handle any address family spec that
                         * immediately follows and potentially
                         * recreate the socket.
                         */
                        nafp = af_getbyname(*argv);
                        if (nafp != NULL) {
                                argc--, argv++;
                                if (nafp != afp) {
                                        close(s);
                                        afp = nafp;
                                        goto top;
                                }
                        }

                        /* Look for a normal parameter. */
                        continue;
                }
                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!",
                              IfName, afp->af_name);
                        clearaddr = false;
                }
        }
        if (clearaddr) {
                /* NOTE: Don't use sizeof because af_ridreq is 'void *'. */
                strlcpy(afp->af_ridreq, IfName, IFNAMSIZ);
                if (ioctl(s, afp->af_difaddr, afp->af_ridreq) < 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!",
                              IfName, afp->af_name);
                        newaddr = false;
                }
        }
        if (newaddr && (setaddr || setmask)) {
                /* NOTE: Don't use sizeof because af_addreq is 'void *'. */
                strlcpy(afp->af_addreq, IfName, IFNAMSIZ);
                if (ioctl(s, afp->af_aifaddr, afp->af_addreq) < 0)
                        Perror("ioctl (SIOCAIFADDR)");
        }

        close(s);
        return (0);
}

static void
setifaddr(const char *addr, int dummy __unused, int s __unused,
          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 = true;
        if (doalias == 0 && afp->af_af != AF_LINK)
                clearaddr = true;
        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);
}

static void
deletetunnel(const char *arg __unused, int dummy __unused, int s,
             const struct afswtch *afp __unused)
{
        struct ifreq ifr;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));

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

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

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

static void
notealias(const char *addr __unused, int param, int s __unused,
          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)
                        memcpy(rqtosa(af_ridreq), rqtosa(af_addreq),
                               rqtosa(af_addreq)->sa_len);
        }
#undef rqtosa

        doalias = param;
        if (param < 0) {
                clearaddr = true;
                newaddr = false;
        } else {
                clearaddr = false;
        }
}

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

static int
getifflags(const char *ifname, int us)
{
        struct ifreq ifr;
        int s;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));

        s = us;
        if (us < 0) {
                if ((s = socket(AF_LOCAL, SOCK_DGRAM, 0)) < 0)
                        err(1, "socket(family AF_LOCAL,SOCK_DGRAM)");
        }

        if (ioctl(s, SIOCGIFFLAGS, &ifr) < 0)
                Perror("ioctl (SIOCGIFFLAGS)");

        if (us < 0)
                close(s);

        return ((ifr.ifr_flags & 0xffff) | (ifr.ifr_flagshigh << 16));
}

static void
setifflags(const char *vname, int value, int s,
           const struct afswtch *afp __unused)
{
        struct ifreq ifr;
        int flags;

        flags = getifflags(IfName, s);
        if (value < 0) {
                value = -value;
                flags &= ~value;
        } else {
                flags |= value;
        }

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));
        ifr.ifr_flags = flags & 0xffff;
        ifr.ifr_flagshigh = flags >> 16;

        if (ioctl(s, SIOCSIFFLAGS, &ifr) < 0)
                Perror(vname);
}

void
setifcap(const char *vname, int value, int s,
         const struct afswtch *afp __unused)
{
        struct ifreq ifr;
        int flags;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));

        if (ioctl(s, SIOCGIFCAP, &ifr) < 0)
                Perror("ioctl (SIOCGIFCAP)");

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

static void
setifmetric(const char *val, int dummy __unused, int s,
            const struct afswtch *afp __unused)
{
        struct ifreq ifr;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof (ifr.ifr_name));
        ifr.ifr_metric = atoi(val);

        if (ioctl(s, SIOCSIFMETRIC, &ifr) < 0)
                err(1, "ioctl SIOCSIFMETRIC (set metric)");
}

static void
setifmtu(const char *val, int dummy __unused, int s,
         const struct afswtch *afp __unused)
{
        struct ifreq ifr;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof (ifr.ifr_name));
        ifr.ifr_mtu = atoi(val);

        if (ioctl(s, SIOCSIFMTU, &ifr) < 0)
                err(1, "ioctl SIOCSIFMTU (set mtu)");
}

static void
setiftsolen(const char *val, int dummy __unused, int s,
            const struct afswtch *afp __unused)
{
        struct ifreq ifr;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof (ifr.ifr_name));
        ifr.ifr_tsolen = atoi(val);

        if (ioctl(s, SIOCSIFTSOLEN, &ifr) < 0)
                err(1, "ioctl SIOCSIFTSOLEN (set tsolen)");
}

static void
setifname(const char *val, int dummy __unused, int s,
          const struct afswtch *afp __unused)
{
        struct ifreq ifr;
        char newname[IFNAMSIZ];
        int n;

        n = snprintf(newname, sizeof(newname), "%s", val);
        if (n >= (int)sizeof(newname))
                errx(1, "ifname too long");

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));
        ifr.ifr_data = newname;

        if (ioctl(s, SIOCSIFNAME, &ifr) < 0)
                err(1, "ioctl SIOCSIFNAME (set name)");

        printifname = true;
        strlcpy(IfName, newname, sizeof(IfName));
}

static void
setifpollcpu(const char *val __unused, int dummy __unused, int s,
             const struct afswtch *afp)
{
        warnx("pollcpu is deprecated, use polling or npolling instead");
        setifflags("npolling", IFF_NPOLLING, s, afp);
}

static void
setifdescr(const char *val, int dummy __unused, int s,
           const struct afswtch *afp __unused)
{
        struct ifreq ifr;
        char *newdescr;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));

        ifr.ifr_buffer.length = strlen(val) + 1;
        if (ifr.ifr_buffer.length == 1) {
                ifr.ifr_buffer.buffer = newdescr = NULL;
                ifr.ifr_buffer.length = 0;
        } else {
                newdescr = strdup(val);
                ifr.ifr_buffer.buffer = newdescr;
                if (newdescr == NULL) {
                        warn("no memory to set ifdescr");
                        return;
                }
        }

        if (ioctl(s, SIOCSIFDESCR, &ifr) < 0)
                warn("ioctl (set descr)");

        free(newdescr);
}

static void
unsetifdescr(const char *val __unused, int dummy __unused, int s,
             const struct afswtch *afp __unused)
{
        setifdescr("", 0, s, 0);
}

#define IFFBITS \
"\020\1UP\2BROADCAST\3DEBUG\4LOOPBACK\5POINTOPOINT\6SMART\7RUNNING" \
"\10NOARP\11PROMISC\12ALLMULTI\14SIMPLEX\15LINK0\16LINK1\17LINK2" \
"\20MULTICAST\22PPROMISC\23MONITOR\24STATICARP\25NPOLLING\26IDIRECT" \
"\27BRIDGE\30PROXY"

#define IFCAPBITS \
"\020\1RXCSUM\2TXCSUM\3NETCONS\4VLAN_MTU\5VLAN_HWTAGGING\6JUMBO_MTU\7RSS" \
"\10VLAN_HWCSUM\11TSO"

/*
 * 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, const struct sockaddr_dl *sdl __unused,
       struct ifaddrs *ifa)
{
        struct ifreq ifr;
        struct ifstat ifs;
        struct ifaddrs *ift;
        bool allfamilies;
        int s;

        memset(&ifr, 0, sizeof(ifr));
        strlcpy(ifr.ifr_name, IfName, sizeof(ifr.ifr_name));

        if (afp == NULL) {
                allfamilies = true;
                ifr.ifr_addr.sa_family = AF_LOCAL;
        } else {
                allfamilies = false;
                ifr.ifr_addr.sa_family =
                    afp->af_af == AF_LINK ? AF_LOCAL : afp->af_af;
        }

        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: ", IfName);
        printb("flags", ifa->ifa_flags, IFFBITS);
        if (ioctl(s, SIOCGIFMETRIC, &ifr) != -1)
                printf(" metric %d", ifr.ifr_metric);
        if (ioctl(s, SIOCGIFMTU, &ifr) != -1)
                printf(" mtu %d", ifr.ifr_mtu);
        putchar('\n');

        for (;;) {
                if ((descr = reallocf(descr, descrlen)) != NULL) {
                        ifr.ifr_buffer.buffer = descr;
                        ifr.ifr_buffer.length = descrlen;
                        if (ioctl(s, SIOCGIFDESCR, &ifr) == 0) {
                                if (ifr.ifr_buffer.length > 1)
                                        printf("\tdescription: %s\n", descr);
                        } else if (errno == ENOMSG) {
                                break;
                        } else if (errno == ENAMETOOLONG) {
                                descrlen = ifr.ifr_buffer.length;
                                continue;
                        } else {
                                warn("ioctl (get descr)");
                        }
                } else {
                        warn("unable to allocate memory for interface "
                            "description");
                }
                break;
        }

        if (ioctl(s, SIOCGIFCAP, &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');
                        if (ifr.ifr_reqcap & IFCAP_TSO) {
                                if (ioctl(s, SIOCGIFTSOLEN, &ifr) == 0) {
                                        printf("\ttsolen %d", ifr.ifr_tsolen);
                                        putchar('\n');
                                }
                        }
                }
        }

        tunnel_status(s);

        for (ift = ifa; ift != NULL; ift = ift->ifa_next) {
                if (ift->ifa_addr == NULL)
                        continue;
                if (strcmp(ifa->ifa_name, ift->ifa_name) != 0)
                        continue;
                if (allfamilies) {
                        const struct afswtch *p;
                        p = af_getbyfamily(ift->ifa_addr->sa_family);
                        if (p != NULL && p->af_status != NULL)
                                p->af_status(s, ift);
                } else if (afp->af_af == ift->ifa_addr->sa_family)
                        afp->af_status(s, ift);
        }
#if 0
        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);
                }
        }
#endif
        if (allfamilies)
                af_other_status(s);
        else if (afp->af_other_status != NULL)
                afp->af_other_status(s);

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

        close(s);
}

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 %pb%i format of the kernel's kprintf()
 */
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(const char *name)
{
#define MOD_PREFIX      "if_"
        struct module_stat mstat;
        int fileid, modid;
        char ifkind[IFNAMSIZ + sizeof(MOD_PREFIX) - 1], ifname[IFNAMSIZ], *dp;
        const char *cp;

        /* loading suppressed by the user */
        if (noload)
                return;

        /* trim the interface number off the end */
        strlcpy(ifname, name, sizeof(ifname));
        for (dp = ifname; *dp != 0; dp++) {
                if (isdigit(*dp)) {
                        *dp = 0;
                        break;
                }
        }

        /* turn interface and unit into module name */
        snprintf(ifkind, sizeof(ifkind), "%s%s", MOD_PREFIX, ifname);

        /* 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 (strcmp(ifname, cp) == 0 || strcmp(ifkind, 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_ARG("description",              setifdescr),
        DEF_CMD_ARG("descr",                    setifdescr),
        DEF_CMD("-description", 0,              unsetifdescr),
        DEF_CMD("-descr",       0,              unsetifdescr),
        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),
        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("proxy",        IFF_ANNOUNCE,   setifflags),
        DEF_CMD("-proxy",       -IFF_ANNOUNCE,  setifflags),
        DEF_CMD("monitor",      IFF_MONITOR,    setifflags),
        DEF_CMD("-monitor",     -IFF_MONITOR,   setifflags),
        DEF_CMD("staticarp",    IFF_STATICARP,  setifflags),
        DEF_CMD("-staticarp",   -IFF_STATICARP, setifflags),
        DEF_CMD("polling",      IFF_NPOLLING,   setifflags),
        DEF_CMD("-polling",     -IFF_NPOLLING,  setifflags),
        DEF_CMD("npolling",     IFF_NPOLLING,   setifflags),
        DEF_CMD("-npolling",    -IFF_NPOLLING,  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("rss",          IFCAP_RSS,      setifcap),
        DEF_CMD("-rss",         -IFCAP_RSS,     setifcap),
        DEF_CMD("tso",          IFCAP_TSO,      setifcap),
        DEF_CMD("-tso",         -IFCAP_TSO,     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),
        DEF_CMD_ARG("tsolen",                   setiftsolen)
};

__constructor(101)
static void
ifconfig_ctor(void)
{
        size_t i;

        for (i = 0; i < nitems(basic_cmds);  i++)
                cmd_register(&basic_cmds[i]);
}