/*-
 * Copyright (c) 2002-2003,2010 Luigi Rizzo
 * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
 * Copyright (c) 1994 Ugen J.S.Antsilevich
 *
 * Idea and grammar partially left from:
 * Copyright (c) 1993 Daniel Boulet
 *
 * Redistribution and use in source forms, with and without modification,
 * are permitted provided that this entire comment appears intact.
 *
 * Redistribution in binary form may occur without any restrictions.
 * Obviously, it would be nice if you gave credit where credit is due
 * but requiring it would be too onerous.
 *
 * This software is provided ``AS IS'' without any warranties of any kind.
 *
 * Command line interface for IP firewall facility
 */

#include <sys/wait.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>
#include <libgen.h>

#include "ipfw2.h"

static void
help(void)
{
        if (is_ipfw()) {
                fprintf(stderr,
"ipfw syntax summary (but please do read the ipfw(8) manpage):\n\n"
"\tipfw [-abcdefhnNqStTv] <command>\n\n"
"where <command> is one of the following:\n\n"
"add [num] [set N] [prob x] RULE-BODY\n"
"{pipe|queue} N config PIPE-BODY\n"
"[pipe|queue] {zero|delete|show} [N{,N}]\n"
"nat N config {ip IPADDR|if IFNAME|log|deny_in|same_ports|unreg_only|unreg_cgn|udp_eim|\n"
"               reset|reverse|proxy_only|redirect_addr linkspec|\n"
"               redirect_port linkspec|redirect_proto linkspec|\n"
"               port_range lower-upper}\n"
"set [disable N... enable N...] | move [rule] X to Y | swap X Y | show\n"
"set N {show|list|zero|resetlog|delete} [N{,N}] | flush\n"
"table N {add ip[/bits] [value] | delete ip[/bits] | flush | list}\n"
"table all {flush | list}\n"
"\n"
"RULE-BODY:     check-state [PARAMS] | ACTION [PARAMS] ADDR [OPTION_LIST]\n"
"ACTION:        check-state | allow | count | deny | unreach{,6} CODE |\n"
"               skipto N | {divert|tee} PORT | forward ADDR |\n"
"               pipe N | queue N | nat N | setfib FIB | reass\n"
"PARAMS:        [log [logamount LOGLIMIT]] [altq QUEUE_NAME]\n"
"ADDR:          [ MAC dst src ether_type ] \n"
"               [ ip from IPADDR [ PORT ] to IPADDR [ PORTLIST ] ]\n"
"               [ ipv6|ip6 from IP6ADDR [ PORT ] to IP6ADDR [ PORTLIST ] ]\n"
"IPADDR:        [not] { any | me | ip/bits{x,y,z} | table(t[,v]) | IPLIST }\n"
"IP6ADDR:       [not] { any | me | me6 | ip6/bits | IP6LIST }\n"
"IP6LIST:       { ip6 | ip6/bits }[,IP6LIST]\n"
"IPLIST:        { ip | ip/bits | ip:mask }[,IPLIST]\n"
"OPTION_LIST:   OPTION [OPTION_LIST]\n"
"OPTION:        bridged | diverted | diverted-loopback | diverted-output |\n"
"       {dst-ip|src-ip} IPADDR | {dst-ip6|src-ip6|dst-ipv6|src-ipv6} IP6ADDR |\n"
"       {dst-port|src-port} LIST |\n"
"       estab | frag | {gid|uid} N | icmptypes LIST | in | out | ipid LIST |\n"
"       iplen LIST | ipoptions SPEC | ipprecedence | ipsec | iptos SPEC |\n"
"       ipttl LIST | ipversion VER | keep-state | layer2 | limit ... |\n"
"       icmp6types LIST | ext6hdr LIST | flow-id N[,N] | fib FIB |\n"
"       mac ... | mac-type LIST | proto LIST | {recv|xmit|via} {IF|IPADDR} |\n"
"       setup | {tcpack|tcpseq|tcpwin} NN | tcpflags SPEC | tcpoptions SPEC |\n"
"       tcpdatalen LIST | verrevpath | versrcreach | antispoof\n"
);
        } else {
                fprintf(stderr,
"dnctl syntax summary (but please do read the dnctl(8) manpage):\n\n"
"\tdnctl [-hnsv] <command>\n\n"
"where <command> is one of the following:\n\n"
"[pipe|queue|sched] N config PIPE-BODY\n"
"[pipe|queue|sched] {delete|list|show} [N{,N}]\n"
"\n"
);
        }

        exit(0);
}

/*
 * Called with the arguments, including program name because getopt
 * wants it to be present.
 * Returns 0 if successful, 1 if empty command, errx() in case of errors.
 * First thing we do is process parameters creating an argv[] array
 * which includes the program name and a NULL entry at the end.
 * If we are called with a single string, we split it on whitespace.
 * Also, arguments with a trailing ',' are joined to the next one.
 * The pointers (av[]) and data are in a single chunk of memory.
 * av[0] points to the original program name, all other entries
 * point into the allocated chunk.
 */
static int
ipfw_main(int oldac, char **oldav)
{
        int ch, ac;
        const char *errstr;
        char **av, **save_av;
        int do_acct = 0;                /* Show packet/byte count */
        int try_next = 0;               /* set if pipe cmd not found */
        int av_size;                    /* compute the av size */
        char *av_p;                     /* used to build the av list */

#define WHITESP         " \t\f\v\n\r"
        if (oldac < 2)
                return 1;       /* need at least one argument */

        if (oldac == 2) {
                /*
                 * If we are called with one argument, try to split it into
                 * words for subsequent parsing. Spaces after a ',' are
                 * removed by copying the string in-place.
                 */
                char *arg = oldav[1];   /* The string is the first arg. */
                int l = strlen(arg);
                int copy = 0;           /* 1 if we need to copy, 0 otherwise */
                int i, j;

                for (i = j = 0; i < l; i++) {
                        if (arg[i] == '#')      /* comment marker */
                                break;
                        if (copy) {
                                arg[j++] = arg[i];
                                copy = !strchr("," WHITESP, arg[i]);
                        } else {
                                copy = !strchr(WHITESP, arg[i]);
                                if (copy)
                                        arg[j++] = arg[i];
                        }
                }
                if (!copy && j > 0)     /* last char was a 'blank', remove it */
                        j--;
                l = j;                  /* the new argument length */
                arg[j++] = '\0';
                if (l == 0)             /* empty string! */
                        return 1;

                /*
                 * First, count number of arguments. Because of the previous
                 * processing, this is just the number of blanks plus 1.
                 */
                for (i = 0, ac = 1; i < l; i++)
                        if (strchr(WHITESP, arg[i]) != NULL)
                                ac++;

                /*
                 * Allocate the argument list structure as a single block
                 * of memory, containing pointers and the argument
                 * strings. We include one entry for the program name
                 * because getopt expects it, and a NULL at the end
                 * to simplify further parsing.
                 */
                ac++;           /* add 1 for the program name */
                av_size = (ac+1) * sizeof(char *) + l + 1;
                av = safe_calloc(av_size, 1);

                /*
                 * Init the argument pointer to the end of the array
                 * and copy arguments from arg[] to av[]. For each one,
                 * j is the initial character, i is the one past the end.
                 */
                av_p = (char *)&av[ac+1];
                for (ac = 1, i = j = 0; i < l; i++) {
                        if (strchr(WHITESP, arg[i]) != NULL || i == l-1) {
                                if (i == l-1)
                                        i++;
                                bcopy(arg+j, av_p, i-j);
                                av[ac] = av_p;
                                av_p += i-j;    /* the length of the string */
                                *av_p++ = '\0';
                                ac++;
                                j = i + 1;
                        }
                }
        } else {
                /*
                 * If an argument ends with ',' join with the next one.
                 */
                int first, i, l=0;

                /*
                 * Allocate the argument list structure as a single block
                 * of memory, containing both pointers and the argument
                 * strings. We include some space for the program name
                 * because getopt expects it.
                 * We add an extra pointer to the end of the array,
                 * to make simpler further parsing.
                 */
                for (i=0; i<oldac; i++)
                        l += strlen(oldav[i]);

                av_size = (oldac+1) * sizeof(char *) + l + oldac;
                av = safe_calloc(av_size, 1);

                /*
                 * Init the argument pointer to the end of the array
                 * and copy arguments from arg[] to av[]
                 */
                av_p = (char *)&av[oldac+1];
                for (first = i = ac = 1, l = 0; i < oldac; i++) {
                        char *arg = oldav[i];
                        int k = strlen(arg);

                        l += k;
                        if (arg[k-1] != ',' || i == oldac-1) {
                                /* Time to copy. */
                                av[ac] = av_p;
                                for (l=0; first <= i; first++) {
                                        strcat(av_p, oldav[first]);
                                        av_p += strlen(oldav[first]);
                                }
                                *av_p++ = '\0';
                                ac++;
                                l = 0;
                                first = i+1;
                        }
                }
        }

        /*
         * set the progname pointer to the original string
         * and terminate the array with null
         */
        av[0] = oldav[0];
        av[ac] = NULL;

        /* Set the force flag for non-interactive processes */
        if (!g_co.do_force)
                g_co.do_force = !isatty(STDIN_FILENO);

#ifdef EMULATE_SYSCTL /* sysctl emulation */
        if (is_ipfw() && ac >= 2 &&
            !strcmp(av[1], "sysctl")) {
                char *s;
                int i;

                if (ac != 3) {
                        printf( "sysctl emulation usage:\n"
                                "       ipfw sysctl name[=value]\n"
                                "       ipfw sysctl -a\n");
                        return 0;
                }
                s = strchr(av[2], '=');
                if (s == NULL) {
                        s = !strcmp(av[2], "-a") ? NULL : av[2];
                        sysctlbyname(s, NULL, NULL, NULL, 0);
                } else {        /* ipfw sysctl x.y.z=value */
                        /* assume an INT value, will extend later */
                        if (s[1] == '\0') {
                                printf("ipfw sysctl: missing value\n\n");
                                return 0;
                        }
                        *s = '\0';
                        i = strtol(s+1, NULL, 0);
                        sysctlbyname(av[2], NULL, NULL, &i, sizeof(int));
                }
                return 0;
        }
#endif

        /* Save arguments for final freeing of memory. */
        save_av = av;

        optind = optreset = 1;  /* restart getopt() */
        if (is_ipfw()) {
                while ((ch = getopt(ac, av, "abcdDefhinNp:qs:STtvx")) != -1)
                        switch (ch) {
                        case 'a':
                                do_acct = 1;
                                break;

                        case 'b':
                                g_co.comment_only = 1;
                                g_co.do_compact = 1;
                                break;

                        case 'c':
                                g_co.do_compact = 1;
                                break;

                        case 'd':
                                g_co.do_dynamic = 1;
                                break;

                        case 'D':
                                g_co.do_dynamic = 2;
                                break;

                        case 'e':
                                /* nop for compatibility */
                                break;

                        case 'f':
                                g_co.do_force = 1;
                                break;

                        case 'h': /* help */
                                free(save_av);
                                help();
                                break;  /* NOTREACHED */

                        case 'i':
                                g_co.do_value_as_ip = 1;
                                break;

                        case 'n':
                                g_co.test_only = 1;
                                break;

                        case 'N':
                                g_co.do_resolv = 1;
                                break;

                        case 'p':
                                errx(EX_USAGE, "An absolute pathname must be used "
                                    "with -p option.");
                                /* NOTREACHED */

                        case 'q':
                                g_co.do_quiet = 1;
                                break;

                        case 's': /* sort */
                                g_co.do_sort = atoi(optarg);
                                break;

                        case 'S':
                                g_co.show_sets = 1;
                                break;

                        case 't':
                                g_co.do_time = TIMESTAMP_STRING;
                                break;

                        case 'T':
                                g_co.do_time = TIMESTAMP_NUMERIC;
                                break;

                        case 'v': /* verbose */
                                g_co.verbose = 1;
                                break;

                        case 'x': /* debug output */
                                g_co.debug_only = 1;
                                break;

                        default:
                                free(save_av);
                                return 1;
                        }
        } else {
                while ((ch = getopt(ac, av, "hns:v")) != -1)
                        switch (ch) {

                        case 'h': /* help */
                                free(save_av);
                                help();
                                break;  /* NOTREACHED */

                        case 'n':
                                g_co.test_only = 1;
                                break;

                        case 's': /* sort */
                                g_co.do_sort = atoi(optarg);
                                break;

                        case 'v': /* verbose */
                                g_co.verbose = 1;
                                break;

                        default:
                                free(save_av);
                                return 1;
                        }

        }

        ac -= optind;
        av += optind;
        NEED1("bad arguments, for usage summary ``ipfw''");

        /*
         * An undocumented behaviour of ipfw1 was to allow rule numbers first,
         * e.g. "100 add allow ..." instead of "add 100 allow ...".
         * In case, swap first and second argument to get the normal form.
         */
        if (ac > 1 && isdigit(*av[0])) {
                char *p = av[0];

                av[0] = av[1];
                av[1] = p;
        }

        /*
         * Optional: pipe, queue or nat.
         */
        g_co.do_nat = 0;
        g_co.do_pipe = 0;
        g_co.use_set = 0;
        if (is_ipfw() && !strncmp(*av, "nat", strlen(*av)))
                g_co.do_nat = 1;
        else if (!strncmp(*av, "pipe", strlen(*av)))
                g_co.do_pipe = 1;
        else if (_substrcmp(*av, "queue") == 0)
                g_co.do_pipe = 2;
        else if (_substrcmp(*av, "flowset") == 0)
                g_co.do_pipe = 2;
        else if (_substrcmp(*av, "sched") == 0)
                g_co.do_pipe = 3;
        else if (is_ipfw() && !strncmp(*av, "set", strlen(*av))) {
                if (ac > 1 && isdigit(av[1][0])) {
                        g_co.use_set = strtonum(av[1], 0, resvd_set_number,
                                        &errstr);
                        if (errstr)
                                errx(EX_DATAERR,
                                    "invalid set number %s\n", av[1]);
                        ac -= 2; av += 2; g_co.use_set++;
                }
        }

        if (g_co.do_pipe || g_co.do_nat) {
                ac--;
                av++;
        }
        NEED1("missing command");

        /*
         * For pipes, queues and nats we normally say 'nat|pipe NN config'
         * but the code is easier to parse as 'nat|pipe config NN'
         * so we swap the two arguments.
         */
        if ((g_co.do_pipe || g_co.do_nat) && ac > 1 && isdigit(*av[0])) {
                char *p = av[0];

                av[0] = av[1];
                av[1] = p;
        }

        if (! is_ipfw() && g_co.do_pipe == 0) {
                help();
        }

        if (g_co.use_set == 0) {
                if (is_ipfw() && _substrcmp(*av, "add") == 0)
                        ipfw_add(av);
                else if (g_co.do_nat && _substrcmp(*av, "show") == 0)
                        ipfw_show_nat(ac, av);
                else if (g_co.do_pipe && _substrcmp(*av, "config") == 0)
                        ipfw_config_pipe(ac, av);
                else if (g_co.do_nat && _substrcmp(*av, "config") == 0)
                        ipfw_config_nat(ac, av);
                else if (is_ipfw() && _substrcmp(*av, "set") == 0)
                        ipfw_sets_handler(av);
                else if (is_ipfw() && _substrcmp(*av, "table") == 0)
                        ipfw_table_handler(ac, av);
                else if (is_ipfw() && _substrcmp(*av, "enable") == 0)
                        ipfw_sysctl_handler(av, 1);
                else if (is_ipfw() && _substrcmp(*av, "disable") == 0)
                        ipfw_sysctl_handler(av, 0);
                else
                        try_next = 1;
        }

        if (g_co.use_set || try_next) {
                if (_substrcmp(*av, "delete") == 0)
                        ipfw_delete(av);
                else if (is_ipfw() && !strncmp(*av, "nat64clat", strlen(*av)))
                        ipfw_nat64clat_handler(ac, av);
                else if (is_ipfw() && !strncmp(*av, "nat64stl", strlen(*av)))
                        ipfw_nat64stl_handler(ac, av);
                else if (is_ipfw() && !strncmp(*av, "nat64lsn", strlen(*av)))
                        ipfw_nat64lsn_handler(ac, av);
                else if (is_ipfw() && !strncmp(*av, "nptv6", strlen(*av)))
                        ipfw_nptv6_handler(ac, av);
                else if (_substrcmp(*av, "flush") == 0)
                        ipfw_flush(g_co.do_force);
                else if (is_ipfw() && _substrcmp(*av, "zero") == 0)
                        ipfw_zero(ac, av, 0 /* IP_FW_ZERO */);
                else if (is_ipfw() && _substrcmp(*av, "resetlog") == 0)
                        ipfw_zero(ac, av, 1 /* IP_FW_RESETLOG */);
                else if (_substrcmp(*av, "print") == 0 ||
                         _substrcmp(*av, "list") == 0)
                        ipfw_list(ac, av, do_acct);
                else if (_substrcmp(*av, "show") == 0)
                        ipfw_list(ac, av, 1 /* show counters */);
                else if (is_ipfw() && _substrcmp(*av, "table") == 0)
                        ipfw_table_handler(ac, av);
                else if (is_ipfw() && _substrcmp(*av, "internal") == 0)
                        ipfw_internal_handler(ac, av);
                else
                        errx(EX_USAGE, "bad command `%s'", *av);
        }

        /* Free memory allocated in the argument parsing. */
        free(save_av);
        return 0;
}


static void
ipfw_readfile(int ac, char *av[])
{
#define MAX_ARGS        32
        char buf[4096];
        char *progname = av[0];         /* original program name */
        const char *cmd = NULL;         /* preprocessor name, if any */
        const char *filename = av[ac-1]; /* file to read */
        int     c, lineno=0;
        FILE    *f = NULL;
        pid_t   preproc = 0;

        if (is_ipfw()) {
                while ((c = getopt(ac, av, "cfNnp:qS")) != -1) {
                        switch(c) {
                        case 'c':
                                g_co.do_compact = 1;
                                break;

                        case 'f':
                                g_co.do_force = 1;
                                break;

                        case 'N':
                                g_co.do_resolv = 1;
                                break;

                        case 'n':
                                g_co.test_only = 1;
                                break;

                        case 'p':
                                /*
                                 * ipfw -p cmd [args] filename
                                 *
                                 * We are done with getopt(). All arguments
                                 * except the filename go to the preprocessor,
                                 * so we need to do the following:
                                 * - check that a filename is actually present;
                                 * - advance av by optind-1 to skip arguments
                                 *   already processed;
                                 * - decrease ac by optind, to remove the args
                                 *   already processed and the final filename;
                                 * - set the last entry in av[] to NULL so
                                 *   popen() can detect the end of the array;
                                 * - set optind=ac to let getopt() terminate.
                                 */
                                if (optind == ac)
                                        errx(EX_USAGE, "no filename argument");
                                cmd = optarg;
                                av[ac-1] = NULL;
                                av += optind - 1;
                                ac -= optind;
                                optind = ac;
                                break;

                        case 'q':
                                g_co.do_quiet = 1;
                                break;

                        case 'S':
                                g_co.show_sets = 1;
                                break;

                        default:
                                errx(EX_USAGE, "bad arguments, for usage"
                                     " summary ``ipfw''");
                        }
                }
        } else {
                while ((c = getopt(ac, av, "nq")) != -1) {
                        switch(c) {
                        case 'n':
                                g_co.test_only = 1;
                                break;

                        case 'q':
                                g_co.do_quiet = 1;
                                break;

                        default:
                                errx(EX_USAGE, "bad arguments, for usage"
                                     " summary ``dnctl''");
                        }
                }
        }

        if (cmd == NULL && ac != optind + 1)
                errx(EX_USAGE, "extraneous filename arguments %s", av[ac-1]);

        if ((f = fopen(filename, "r")) == NULL)
                err(EX_UNAVAILABLE, "fopen: %s", filename);

        if (cmd != NULL) {                      /* pipe through preprocessor */
                int pipedes[2];

                if (pipe(pipedes) == -1)
                        err(EX_OSERR, "cannot create pipe");

                preproc = fork();
                if (preproc == -1)
                        err(EX_OSERR, "cannot fork");

                if (preproc == 0) {
                        /*
                         * Child, will run the preprocessor with the
                         * file on stdin and the pipe on stdout.
                         */
                        if (dup2(fileno(f), 0) == -1
                            || dup2(pipedes[1], 1) == -1)
                                err(EX_OSERR, "dup2()");
                        fclose(f);
                        close(pipedes[1]);
                        close(pipedes[0]);
                        execvp(cmd, av);
                        err(EX_OSERR, "execvp(%s) failed", cmd);
                } else { /* parent, will reopen f as the pipe */
                        fclose(f);
                        close(pipedes[1]);
                        if ((f = fdopen(pipedes[0], "r")) == NULL) {
                                int savederrno = errno;

                                (void)kill(preproc, SIGTERM);
                                errno = savederrno;
                                err(EX_OSERR, "fdopen()");
                        }
                }
        }

        while (fgets(buf, sizeof(buf), f)) {            /* read commands */
                char linename[20];
                char *args[2];

                lineno++;
                snprintf(linename, sizeof(linename), "Line %d", lineno);
                setprogname(linename); /* XXX */
                args[0] = progname;
                args[1] = buf;
                ipfw_main(2, args);
        }
        fclose(f);
        if (cmd != NULL) {
                int status;

                if (waitpid(preproc, &status, 0) == -1)
                        errx(EX_OSERR, "waitpid()");
                if (WIFEXITED(status) && WEXITSTATUS(status) != EX_OK)
                        errx(EX_UNAVAILABLE,
                            "preprocessor exited with status %d",
                            WEXITSTATUS(status));
                else if (WIFSIGNALED(status))
                        errx(EX_UNAVAILABLE,
                            "preprocessor exited with signal %d",
                            WTERMSIG(status));
        }
}

int
main(int ac, char *av[])
{
#if defined(_WIN32) && defined(TCC)
        {
                WSADATA wsaData;
                int ret=0;
                unsigned short wVersionRequested = MAKEWORD(2, 2);
                ret = WSAStartup(wVersionRequested, &wsaData);
                if (ret != 0) {
                        /* Tell the user that we could not find a usable */
                        /* Winsock DLL.                           */
                        printf("WSAStartup failed with error: %d\n", ret);
                        return 1;
                }
        }
#endif

        if (strcmp("dnctl", basename(av[0])) == 0)
                g_co.prog = cmdline_prog_dnctl;
        else
                g_co.prog = cmdline_prog_ipfw;

        /*
         * If the last argument is an absolute pathname, interpret it
         * as a file to be preprocessed.
         */

        if (ac > 1 && av[ac - 1][0] == '/') {
                if (access(av[ac - 1], R_OK) == 0)
                        ipfw_readfile(ac, av);
                else
                        err(EX_USAGE, "pathname: %s", av[ac - 1]);
        } else {
                if (ipfw_main(ac, av)) {
                        errx(EX_USAGE,
                            "usage: %s [options]\n"
                            "do \"%s -h\" or \"man %s\" for details", av[0],
                            av[0], av[0]);
                }
        }
        return EX_OK;
}