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/**
* Seccomp Library test program
*
* Copyright (c) 2018 Oracle and/or its affiliates. All rights reserved.
* Author: Tom Hromatka <tom.hromatka@oracle.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 <errno.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <seccomp.h>
#include "util.h"
/* arbitrary list of syscalls to force seccomp to generate a binary tree */
static const int denylist[] = {
SCMP_SYS(times),
SCMP_SYS(ptrace),
SCMP_SYS(getuid),
SCMP_SYS(syslog),
SCMP_SYS(getgid),
SCMP_SYS(setuid),
SCMP_SYS(setgid),
SCMP_SYS(geteuid),
SCMP_SYS(getegid),
SCMP_SYS(setpgid),
SCMP_SYS(getppid),
SCMP_SYS(getpgrp),
SCMP_SYS(setsid),
SCMP_SYS(setreuid),
SCMP_SYS(setregid),
SCMP_SYS(getgroups),
SCMP_SYS(setgroups),
SCMP_SYS(setresuid),
SCMP_SYS(getresuid),
SCMP_SYS(setresgid),
SCMP_SYS(getresgid),
SCMP_SYS(getpgid),
SCMP_SYS(setfsuid),
SCMP_SYS(setfsgid),
};
int main(int argc, char *argv[])
{
int rc;
int fd;
int i;
scmp_filter_ctx ctx = NULL;
const char buf[] = "testing";
ssize_t buf_len = strlen(buf);
rc = util_action_parse(argv[1]);
if (rc != SCMP_ACT_ALLOW) {
rc = 1;
goto out;
}
rc = util_trap_install();
if (rc != 0)
goto out;
fd = open("/dev/null", O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
if (fd < 0) {
rc = errno;
goto out;
}
ctx = seccomp_init(SCMP_ACT_TRAP);
if (ctx == NULL)
return ENOMEM;
rc = seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(write), 1,
SCMP_A0(SCMP_CMP_EQ, fd));
if (rc != 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(close), 0);
if (rc != 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(rt_sigreturn), 0);
if (rc != 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_ALLOW, SCMP_SYS(exit_group), 0);
if (rc != 0)
goto out;
for (i = 0; i < (sizeof(denylist) / sizeof(denylist[0])); i++) {
rc = seccomp_rule_add(ctx, SCMP_ACT_KILL, denylist[i], 0);
if (rc != 0)
goto out;
}
rc = seccomp_load(ctx);
if (rc != 0)
goto out;
if (write(fd, buf, buf_len) < buf_len) {
rc = errno;
goto out;
}
if (close(fd) < 0) {
rc = errno;
goto out;
}
rc = 160;
out:
seccomp_release(ctx);
return (rc < 0 ? -rc : rc);
}
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