root/regress/sys/kern/unveil-unmount/unveil-unlink.c
/*      $OpenBSD: unveil-unlink.c,v 1.1.1.1 2019/08/01 15:20:51 bluhm Exp $     */
/*
 * Copyright (c) 2019 Alexander Bluhm <bluhm@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>

int
main(int argc, char *argv[])
{
        char *dir, *file, *path;
        int fd;

        if (argc != 3)
                errx(2, "usage: unveil-unlink dir file");

        dir = argv[1];
        file = argv[2];
        if (asprintf(&path, "%s/%s", dir, file) == -1)
                err(1, "asprintf");

        fd = open(path, O_WRONLY|O_CREAT, 0755);
        if (fd == -1)
                err(1, "open %s", dir);
        close(fd);

        if (unveil(dir, "r") == -1)
                err(1, "unveil %s", dir);
        if (unveil(NULL, NULL) == -1)
                err(1, "unveil NULL");
        if (unlink(path) == 0)
                errx(1, "unlink %s succeeded", path);

        return 0;
}