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/**
* Seccomp Library test program
*
* Copyright (c) 2017 Red Hat <pmoore@redhat.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 <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <seccomp.h>
#include "util.h"
int main(int argc, char *argv[])
{
int rc;
int fd;
scmp_filter_ctx ctx = NULL;
/* stdout */
fd = 1;
rc = seccomp_api_set(3);
if (rc != 0)
return EOPNOTSUPP;
ctx = seccomp_init(SCMP_ACT_ALLOW);
if (ctx == NULL) {
rc = ENOMEM;
goto out;
}
rc = seccomp_arch_remove(ctx, SCMP_ARCH_NATIVE);
if (rc < 0)
goto out;
rc = seccomp_arch_add(ctx, SCMP_ARCH_X86_64);
if (rc < 0)
goto out;
rc = seccomp_arch_add(ctx, SCMP_ARCH_X86);
if (rc < 0)
goto out;
/* NOTE: the syscalls and their arguments have been picked to achieve
* the highest possible code coverage, this is not a useful
* real world filter configuration */
rc = seccomp_rule_add(ctx, SCMP_ACT_KILL, SCMP_SYS(open), 0);
if (rc < 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_KILL, SCMP_SYS(read), 4,
SCMP_A0(SCMP_CMP_EQ, 0),
SCMP_A1(SCMP_CMP_GE, 1),
SCMP_A2(SCMP_CMP_GT, 2),
SCMP_A3(SCMP_CMP_MASKED_EQ, 0x0f, 3));
if (rc < 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_TRAP, SCMP_SYS(write), 3,
SCMP_A0(SCMP_CMP_NE, 0),
SCMP_A1(SCMP_CMP_LE, 1),
SCMP_A2(SCMP_CMP_LT, 2));
if (rc < 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_ERRNO(1), SCMP_SYS(close), 0);
if (rc < 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_TRACE(1), SCMP_SYS(exit), 0);
if (rc < 0)
goto out;
rc = seccomp_rule_add(ctx, SCMP_ACT_KILL_PROCESS, SCMP_SYS(fstat), 0);
if (rc < 0)
goto out;
/* verify the prioritized, but no-rule, syscall */
rc = seccomp_syscall_priority(ctx, SCMP_SYS(poll), 255);
if (rc < 0)
goto out;
rc = seccomp_export_pfc(ctx, fd);
if (rc < 0)
goto out;
out:
seccomp_release(ctx);
close(fd);
return (rc < 0 ? -rc : rc);
}
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