/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2002 Dima Dorfman.
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 */

/*
 * Rule subsystem manipulation.
 */

#include <sys/param.h>
#include <sys/conf.h>
#include <sys/ioctl.h>

#include <assert.h>
#include <err.h>
#include <errno.h>
#include <grp.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "extern.h"

static void rulespec_infp(FILE *fp, unsigned long request, devfs_rsnum rsnum);
static void rulespec_instr(struct devfs_rule *dr, const char *str,
    devfs_rsnum rsnum);
static void rulespec_intok(struct devfs_rule *dr, int ac, char **av,
    devfs_rsnum rsnum);
static void rulespec_outfp(FILE *fp, struct devfs_rule *dr);

static command_t rule_add, rule_apply, rule_applyset;
static command_t rule_del, rule_delset, rule_show, rule_showsets;

static ctbl_t ctbl_rule = {
        { "add",                rule_add },
        { "apply",              rule_apply },
        { "applyset",           rule_applyset },
        { "del",                rule_del },
        { "delset",             rule_delset },
        { "show",               rule_show },
        { "showsets",           rule_showsets },
        { NULL,                 NULL }
};

static struct intstr ist_type[] = {
        { "disk",               D_DISK },
        { "mem",                D_MEM },
        { "tape",               D_TAPE },
        { "tty",                D_TTY },
        { NULL,                 -1 }
};

static devfs_rsnum in_rsnum;

int
rule_main(int ac, char **av)
{
        struct cmd *c;
        int ch;

        setprogname("devfs rule");
        optreset = optind = 1;
        while ((ch = getopt(ac, av, "s:")) != -1)
                switch (ch) {
                case 's':
                        in_rsnum = eatonum(optarg);
                        break;
                default:
                        usage();
                }
        ac -= optind;
        av += optind;
        if (ac < 1)
                usage();

        for (c = ctbl_rule; c->name != NULL; ++c)
                if (strcmp(c->name, av[0]) == 0)
                        exit((*c->handler)(ac, av));
        errx(1, "unknown command: %s", av[0]);
}

static int
rule_add(int ac, char **av)
{
        struct devfs_rule dr;
        int rv;

        if (ac < 2)
                usage();
        if (strcmp(av[1], "-") == 0)
                rulespec_infp(stdin, DEVFSIO_RADD, in_rsnum);
        else {
                rulespec_intok(&dr, ac - 1, av + 1, in_rsnum);
                rv = ioctl(mpfd, DEVFSIO_RADD, &dr);
                if (rv == -1)
                        err(1, "ioctl DEVFSIO_RADD");
        }
        return (0);
}

static int
rule_apply(int ac __unused, char **av __unused)
{
        struct devfs_rule dr;
        devfs_rnum rnum;
        devfs_rid rid;
        int rv;

        if (ac < 2)
                usage();
        if (!atonum(av[1], &rnum)) {
                if (strcmp(av[1], "-") == 0)
                        rulespec_infp(stdin, DEVFSIO_RAPPLY, in_rsnum);
                else {
                        rulespec_intok(&dr, ac - 1, av + 1, in_rsnum);
                        rv = ioctl(mpfd, DEVFSIO_RAPPLY, &dr);
                        if (rv == -1)
                                err(1, "ioctl DEVFSIO_RAPPLY");
                }
        } else {
                rid = mkrid(in_rsnum, rnum);
                rv = ioctl(mpfd, DEVFSIO_RAPPLYID, &rid);
                if (rv == -1)
                        err(1, "ioctl DEVFSIO_RAPPLYID");
        }
        return (0);
}

static int
rule_applyset(int ac, char **av __unused)
{
        int rv;

        if (ac != 1)
                usage();
        rv = ioctl(mpfd, DEVFSIO_SAPPLY, &in_rsnum);
        if (rv == -1)
                err(1, "ioctl DEVFSIO_SAPPLY");
        return (0);
}

static int
rule_del(int ac __unused, char **av)
{
        devfs_rid rid;
        int rv;

        if (av[1] == NULL)
                usage();
        rid = mkrid(in_rsnum, eatoi(av[1]));
        rv = ioctl(mpfd, DEVFSIO_RDEL, &rid);
        if (rv == -1)
                err(1, "ioctl DEVFSIO_RDEL");
        return (0);
}

static int
rule_delset(int ac, char **av __unused)
{
        struct devfs_rule dr;
        int rv;

        if (ac != 1)
                usage();
        memset(&dr, '\0', sizeof(dr));
        dr.dr_magic = DEVFS_MAGIC;
        dr.dr_id = mkrid(in_rsnum, 0);
        while (ioctl(mpfd, DEVFSIO_RGETNEXT, &dr) != -1) {
                rv = ioctl(mpfd, DEVFSIO_RDEL, &dr.dr_id);
                if (rv == -1)
                        err(1, "ioctl DEVFSIO_RDEL");
        }
        if (errno != ENOENT)
                err(1, "ioctl DEVFSIO_RGETNEXT");
        return (0);
}

static int
rule_show(int ac __unused, char **av)
{
        struct devfs_rule dr;
        devfs_rnum rnum;
        int rv;

        memset(&dr, '\0', sizeof(dr));
        dr.dr_magic = DEVFS_MAGIC;
        if (av[1] != NULL) {
                rnum = eatoi(av[1]);
                dr.dr_id = mkrid(in_rsnum, rnum - 1);
                rv = ioctl(mpfd, DEVFSIO_RGETNEXT, &dr);
                if (rv == -1)
                        err(1, "ioctl DEVFSIO_RGETNEXT");
                if (rid2rn(dr.dr_id) == rnum)
                        rulespec_outfp(stdout, &dr);
        } else {
                dr.dr_id = mkrid(in_rsnum, 0);
                while (ioctl(mpfd, DEVFSIO_RGETNEXT, &dr) != -1)
                        rulespec_outfp(stdout, &dr);
                if (errno != ENOENT)
                        err(1, "ioctl DEVFSIO_RGETNEXT");
        }
        return (0);
}

static int
rule_showsets(int ac, char **av __unused)
{
        devfs_rsnum rsnum;

        if (ac != 1)
                usage();
        rsnum = 0;
        while (ioctl(mpfd, DEVFSIO_SGETNEXT, &rsnum) != -1)
                printf("%d\n", rsnum);
        if (errno != ENOENT)
                err(1, "ioctl DEVFSIO_SGETNEXT");
        return (0);
}

int
ruleset_main(int ac, char **av)
{
        devfs_rsnum rsnum;
        int rv;

        setprogname("devfs ruleset");
        if (ac < 2)
                usage();
        rsnum = eatonum(av[1]);
        rv = ioctl(mpfd, DEVFSIO_SUSE, &rsnum);
        if (rv == -1)
                err(1, "ioctl DEVFSIO_SUSE");
        return (0);
}


/*
 * Input rules from a file (probably the standard input).  This
 * differs from the other rulespec_in*() routines in that it also
 * calls ioctl() for the rules, since it is impractical (and not very
 * useful) to return a list (or array) of rules, just so the caller
 * can call ioctl() for each of them.
 */
static void
rulespec_infp(FILE *fp, unsigned long request, devfs_rsnum rsnum)
{
        struct devfs_rule dr;
        char *line;
        int rv;

        assert(fp == stdin);    /* XXX: De-hardcode "stdin" from error msg. */
        while (efgetln(fp, &line)) {
                rulespec_instr(&dr, line, rsnum);
                rv = ioctl(mpfd, request, &dr);
                if (rv == -1)
                        err(1, "ioctl");
                free(line);     /* efgetln() always malloc()s. */
        }
        if (ferror(stdin))
                err(1, "stdin");
}

/*
 * Construct a /struct devfs_rule/ from a string.
 */
static void
rulespec_instr(struct devfs_rule *dr, const char *str, devfs_rsnum rsnum)
{
        char **av;
        int ac;

        tokenize(str, &ac, &av);
        if (ac == 0)
                errx(1, "unexpected end of rulespec");
        rulespec_intok(dr, ac, av, rsnum);
        free(av[0]);
        free(av);
}

/*
 * Construct a /struct devfs_rule/ from ac and av.
 */
static void
rulespec_intok(struct devfs_rule *dr, int ac __unused, char **av,
    devfs_rsnum rsnum)
{
        struct intstr *is;
        struct passwd *pw;
        struct group *gr;
        devfs_rnum rnum;
        void *set;

        memset(dr, '\0', sizeof(*dr));

        /*
         * We don't maintain ac hereinafter.
         */
        if (av[0] == NULL)
                errx(1, "unexpected end of rulespec");

        /* If the first argument is an integer, treat it as a rule number. */
        if (!atonum(av[0], &rnum))
                rnum = 0;               /* auto-number */
        else
                ++av;

        /*
         * These aren't table-driven since that would result in more
         * tiny functions than I care to deal with.
         */
        for (;;) {
                if (av[0] == NULL)
                        break;
                else if (strcmp(av[0], "type") == 0) {
                        if (av[1] == NULL)
                                errx(1, "expecting argument for type");
                        for (is = ist_type; is->s != NULL; ++is)
                                if (strcmp(av[1], is->s) == 0) {
                                        dr->dr_dswflags |= is->i;
                                        break;
                                }
                        if (is->s == NULL)
                                errx(1, "unknown type: %s", av[1]);
                        dr->dr_icond |= DRC_DSWFLAGS;
                        av += 2;
                } else if (strcmp(av[0], "path") == 0) {
                        if (av[1] == NULL)
                                errx(1, "expecting argument for path");
                        if (strlcpy(dr->dr_pathptrn, av[1], DEVFS_MAXPTRNLEN)
                            >= DEVFS_MAXPTRNLEN)
                                warnx("pattern specified too long; truncated");
                        dr->dr_icond |= DRC_PATHPTRN;
                        av += 2;
                } else
                        break;
        }
        while (av[0] != NULL) {
                if (strcmp(av[0], "hide") == 0) {
                        dr->dr_iacts |= DRA_BACTS;
                        dr->dr_bacts |= DRB_HIDE;
                        ++av;
                } else if (strcmp(av[0], "unhide") == 0) {
                        dr->dr_iacts |= DRA_BACTS;
                        dr->dr_bacts |= DRB_UNHIDE;
                        ++av;
                } else if (strcmp(av[0], "user") == 0) {
                        if (av[1] == NULL)
                                errx(1, "expecting argument for user");
                        dr->dr_iacts |= DRA_UID;
                        pw = getpwnam(av[1]);
                        if (pw != NULL)
                                dr->dr_uid = pw->pw_uid;
                        else
                                dr->dr_uid = eatoi(av[1]); /* XXX overflow */
                        av += 2;
                } else if (strcmp(av[0], "group") == 0) {
                        if (av[1] == NULL)
                                errx(1, "expecting argument for group");
                        dr->dr_iacts |= DRA_GID;
                        gr = getgrnam(av[1]);
                        if (gr != NULL)
                                dr->dr_gid = gr->gr_gid;
                        else
                                dr->dr_gid = eatoi(av[1]); /* XXX overflow */
                        av += 2;
                } else if (strcmp(av[0], "mode") == 0) {
                        if (av[1] == NULL)
                                errx(1, "expecting argument for mode");
                        dr->dr_iacts |= DRA_MODE;
                        set = setmode(av[1]);
                        if (set == NULL)
                                errx(1, "invalid mode: %s", av[1]);
                        dr->dr_mode = getmode(set, 0);
                        av += 2;
                } else if (strcmp(av[0], "include") == 0) {
                        if (av[1] == NULL)
                                errx(1, "expecting argument for include");
                        dr->dr_iacts |= DRA_INCSET;
                        dr->dr_incset = eatonum(av[1]);
                        av += 2;
                } else
                        errx(1, "unknown argument: %s", av[0]);
        }

        dr->dr_id = mkrid(rsnum, rnum);
        dr->dr_magic = DEVFS_MAGIC;
}

/*
 * Write a human-readable (and machine-parsable, by rulespec_in*())
 * representation of dr to bufp.  *bufp should be free(3)'d when the
 * caller is finished with it.
 */
static void
rulespec_outfp(FILE *fp, struct devfs_rule *dr)
{
        struct intstr *is;
        struct passwd *pw;
        struct group *gr;

        fprintf(fp, "%d", rid2rn(dr->dr_id));

        if (dr->dr_icond & DRC_DSWFLAGS)
                for (is = ist_type; is->s != NULL; ++is)
                        if (dr->dr_dswflags & is->i)
                                fprintf(fp, " type %s", is->s);
        if (dr->dr_icond & DRC_PATHPTRN)
                fprintf(fp, " path %s", dr->dr_pathptrn);

        if (dr->dr_iacts & DRA_BACTS) {
                if (dr->dr_bacts & DRB_HIDE)
                        fprintf(fp, " hide");
                if (dr->dr_bacts & DRB_UNHIDE)
                        fprintf(fp, " unhide");
        }
        if (dr->dr_iacts & DRA_UID) {
                pw = getpwuid(dr->dr_uid);
                if (pw == NULL)
                        fprintf(fp, " user %d", dr->dr_uid);
                else
                        fprintf(fp, " user %s", pw->pw_name);
        }
        if (dr->dr_iacts & DRA_GID) {
                gr = getgrgid(dr->dr_gid);
                if (gr == NULL)
                        fprintf(fp, " group %d", dr->dr_gid);
                else
                        fprintf(fp, " group %s", gr->gr_name);
        }
        if (dr->dr_iacts & DRA_MODE)
                fprintf(fp, " mode %o", dr->dr_mode);
        if (dr->dr_iacts & DRA_INCSET)
                fprintf(fp, " include %d", dr->dr_incset);

        fprintf(fp, "\n");
}