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/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
*/
#include <AK/String.h>
#include <AK/StringView.h>
#include <stdio.h>
#include <unistd.h>
struct Options {
const char* path;
const char* program { "/bin/Shell" };
int flags { -1 };
};
void print_usage(const char* argv0)
{
fprintf(
stderr,
"Usage:\n"
"\t%s <path> [program] [-o options]\n",
argv0
);
}
Options parse_options(int argc, char** argv)
{
Options options;
if (argc < 2) {
print_usage(argv[0]);
exit(1);
}
options.path = argv[1];
int i = 2;
if (i < argc && argv[i][0] != '-')
options.program = argv[i++];
if (i >= argc)
return options;
if (strcmp(argv[i], "-o") != 0) {
print_usage(argv[0]);
exit(1);
}
i++;
if (i >= argc) {
print_usage(argv[0]);
exit(1);
}
options.flags = 0;
StringView arg = argv[i];
Vector<StringView> parts = arg.split_view(',');
for (auto& part : parts) {
if (part == "defaults")
continue;
else if (part == "nodev")
options.flags |= MS_NODEV;
else if (part == "noexec")
options.flags |= MS_NOEXEC;
else if (part == "nosuid")
options.flags |= MS_NOSUID;
else if (part == "bind")
fprintf(stderr, "Ignoring -o bind, as it doesn't make sense for chroot");
else
fprintf(stderr, "Ignoring invalid option: %s\n", String(part).characters());
}
return options;
}
int main(int argc, char** argv)
{
Options options = parse_options(argc, argv);
if (chroot_with_mount_flags(options.path, options.flags) < 0) {
perror("chroot");
return 1;
}
if (chdir("/") < 0) {
perror("chdir(/)");
return 1;
}
execl(options.program, options.program, nullptr);
perror("execl");
return 1;
}
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