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// Copyright (C) 2023 Intel Corporation.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
#include <string_view>
#include <errno.h>
#include <fcntl.h>
#include <sched.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/resource.h>
#include <unistd.h>
int main(int argc, char **argv)
{
if (argc < 2) {
printf("Usage: %s command [extra]\nSee source code for commands\n",
argv[0]);
return EXIT_FAILURE;
}
std::string_view cmd = argv[1];
errno = 0;
if (cmd.size() == 0) {
// just checking that we did get here
return EXIT_SUCCESS;
}
if (cmd == "reset-ids") {
if (getuid() == geteuid() && getgid() == getegid())
return EXIT_SUCCESS;
fprintf(stderr, "Real: %d %d; Effective: %d %d\n",
getuid(), getgid(), geteuid(), getegid());
return EXIT_FAILURE;
}
if (cmd == "reset-sighand") {
bool ok = true;
// confirm our signal block mask is empty
sigset_t set;
sigprocmask(SIG_SETMASK, nullptr, &set);
for (int signo = 1; signo < NSIG; ++signo) {
if (sigismember(&set, signo)) {
fprintf(stderr, "'%s' is blocked.\n", strsignal(signo));
ok = false;
}
}
// confirm SIGUSR1 was not ignored
struct sigaction action;
sigaction(SIGUSR1, nullptr, &action);
if (action.sa_handler != SIG_DFL) {
fprintf(stderr, "SIGUSR1 is SIG_IGN\n");
ok = false;
}
return ok ? EXIT_SUCCESS : EXIT_FAILURE;
}
if (cmd == "ignore-sigpipe") {
// confirm SIGPIPE was ignored
struct sigaction action;
sigaction(SIGPIPE, nullptr, &action);
if (action.sa_handler == SIG_IGN)
return EXIT_SUCCESS;
fprintf(stderr, "SIGPIPE is SIG_DFL\n");
return EXIT_FAILURE;
}
if (cmd == "file-descriptors") {
int fd = atoi(argv[2]);
if (close(fd) < 0 && errno == EBADF)
return EXIT_SUCCESS;
fprintf(stderr, "%d is a valid file descriptor\n", fd);
return EXIT_FAILURE;
}
if (cmd == "file-descriptors2") {
int fd1 = atoi(argv[2]); // should be open
int fd2 = atoi(argv[3]); // should be closed
if (close(fd1) < 0)
fprintf(stderr, "%d was not a valid file descriptor\n", fd1);
if (close(fd2) == 0 || errno != EBADF)
fprintf(stderr, "%d is a valid file descriptor\n", fd2);
return EXIT_SUCCESS;
}
if (cmd == "noctty") {
int fd = open("/dev/tty", O_RDONLY);
if (fd == -1)
return EXIT_SUCCESS;
fprintf(stderr, "Could open /dev/tty\n");
return EXIT_FAILURE;
}
if (cmd == "no-coredumps") {
struct rlimit corelimit;
if (getrlimit(RLIMIT_CORE, &corelimit) != 0) {
// this shouldn't happen, so just assume it worked
return EXIT_SUCCESS;
}
if (corelimit.rlim_cur == 0)
return EXIT_SUCCESS;
fprintf(stderr, "rlim_cur = %lx\n", (unsigned long)corelimit.rlim_cur);
return EXIT_FAILURE;
}
if (cmd == "setsid") {
pid_t pgid = getpgrp();
if (pgid == getpid())
return EXIT_SUCCESS;
fprintf(stderr, "Process group was %d\n", pgid);
return EXIT_FAILURE;
}
fprintf(stderr, "Unknown command \"%s\"", cmd.data());
return EXIT_FAILURE;
}