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/**
* Seccomp Library test program
*
* Copyright (c) 2019 Cisco Systems, Inc. <pmoore2@cisco.com>
* Author: Paul Moore <paul@paul-moore.com>
*/
/*
* This library is free software; you can redistribute it and/or modify it
* under the terms of version 2.1 of the GNU Lesser General Public License as
* published by the Free Software Foundation.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, see <http://www.gnu.org/licenses>.
*/
#include <sys/types.h>
#include <sys/wait.h>
#include <asm/unistd.h>
#include <unistd.h>
#include <seccomp.h>
#include <signal.h>
#include <syscall.h>
#include <errno.h>
#include <stdlib.h>
#include "util.h"
int main(int argc, char *argv[])
{
int rc, fd = -1, status;
struct seccomp_notif *req = NULL;
struct seccomp_notif_resp *resp = NULL;
scmp_filter_ctx ctx = NULL;
pid_t pid = 0, magic;
magic = getpid();
ctx = seccomp_init(SCMP_ACT_ALLOW);
if (ctx == NULL)
return ENOMEM;
rc = seccomp_rule_add(ctx, SCMP_ACT_NOTIFY, SCMP_SYS(getpid), 0, NULL);
if (rc)
goto out;
rc = seccomp_load(ctx);
if (rc < 0)
goto out;
rc = seccomp_notify_fd(ctx);
if (rc < 0)
goto out;
fd = rc;
pid = fork();
if (pid == 0)
exit(syscall(__NR_getpid) != magic);
rc = seccomp_notify_alloc(&req, &resp);
if (rc)
goto out;
rc = seccomp_notify_receive(fd, req);
if (rc)
goto out;
if (req->data.nr != __NR_getpid) {
rc = -EFAULT;
goto out;
}
rc = seccomp_notify_id_valid(fd, req->id);
if (rc)
goto out;
resp->id = req->id;
resp->val = magic;
resp->error = 0;
resp->flags = 0;
rc = seccomp_notify_respond(fd, resp);
if (rc)
goto out;
if (waitpid(pid, &status, 0) != pid) {
rc = -EFAULT;
goto out;
}
if (!WIFEXITED(status)) {
rc = -EFAULT;
goto out;
}
if (WEXITSTATUS(status)) {
rc = -EFAULT;
goto out;
}
rc = seccomp_reset(ctx, SCMP_ACT_ALLOW);
if (rc < 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_NOTIFY, SCMP_SYS(getppid), 0, NULL);
if (rc)
goto out;
rc = seccomp_load(ctx);
if (rc < 0)
goto out;
rc = seccomp_notify_fd(ctx);
if (rc < 0)
goto out;
if (rc != fd) {
rc = -EFAULT;
goto out;
} else
rc = 0;
out:
if (fd >= 0)
close(fd);
if (pid)
kill(pid, SIGKILL);
seccomp_notify_free(req, resp);
seccomp_release(ctx);
if (rc != 0)
return (rc < 0 ? -rc : rc);
return 160;
}
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