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/**
* Seccomp System Interfaces
*
* Copyright (c) 2012 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>.
*/
#ifndef _SYSTEM_H
#define _SYSTEM_H
#include <inttypes.h>
#include <stdbool.h>
#include <linux/filter.h>
#include <linux/types.h>
#include <sys/prctl.h>
#include <sys/ioctl.h>
#include "configure.h"
/* NOTE: this was taken from the Linux Kernel sources */
#define MAX_ERRNO 4095
struct db_filter_col;
/* NOTE: temporary location, move to include/seccomp.h.in when complete */
enum scmp_kver {
__SCMP_KV_NULL = 0,
SCMP_KV_UNDEF = 1,
/* TODO: add SCMP_KV_X_YY values as the syscall table is populated */
__SCMP_KV_MAX,
};
#ifdef HAVE_LINUX_SECCOMP_H
/* system header file */
#include <linux/seccomp.h>
#else
/* NOTE: the definitions below were taken from the Linux Kernel sources */
/* Valid values for seccomp.mode and prctl(PR_SET_SECCOMP, <mode>) */
#define SECCOMP_MODE_DISABLED 0 /* seccomp is not in use. */
#define SECCOMP_MODE_STRICT 1 /* uses hard-coded filter. */
#define SECCOMP_MODE_FILTER 2 /* uses user-supplied filter. */
/*
* All BPF programs must return a 32-bit value.
* The bottom 16-bits are for optional return data.
* The upper 16-bits are ordered from least permissive values to most.
*
* The ordering ensures that a min_t() over composed return values always
* selects the least permissive choice.
*/
#define SECCOMP_RET_KILL_PROCESS 0x80000000U /* kill the process immediately */
#define SECCOMP_RET_KILL_THREAD 0x00000000U /* kill the thread immediately */
#define SECCOMP_RET_KILL SECCOMP_RET_KILL_THREAD /* default to killing the thread */
#define SECCOMP_RET_TRAP 0x00030000U /* disallow and force a SIGSYS */
#define SECCOMP_RET_ERRNO 0x00050000U /* returns an errno */
#define SECCOMP_RET_USER_NOTIF 0x7fc00000U /* notifies userspace */
#define SECCOMP_RET_TRACE 0x7ff00000U /* pass to a tracer or disallow */
#define SECCOMP_RET_ALLOW 0x7fff0000U /* allow */
/* Masks for the return value sections. */
#define SECCOMP_RET_ACTION 0x7fff0000U
#define SECCOMP_RET_DATA 0x0000ffffU
/**
* struct seccomp_data - the format the BPF program executes over.
* @nr: the system call number
* @arch: indicates system call convention as an AUDIT_ARCH_* value
* as defined in <linux/audit.h>.
* @instruction_pointer: at the time of the system call.
* @args: up to 6 system call arguments always stored as 64-bit values
* regardless of the architecture.
*/
struct seccomp_data {
int nr;
__u32 arch;
__u64 instruction_pointer;
__u64 args[6];
};
#endif /* HAVE_LINUX_SECCOMP_H */
/* rename some of the socket filter types to make more sense */
typedef struct sock_filter bpf_instr_raw;
/* no new privs definitions */
#ifndef PR_SET_NO_NEW_PRIVS
#define PR_SET_NO_NEW_PRIVS 38
#endif
#ifndef PR_GET_NO_NEW_PRIVS
#define PR_GET_NO_NEW_PRIVS 39
#endif
/* operations for the seccomp() syscall */
#ifndef SECCOMP_SET_MODE_STRICT
#define SECCOMP_SET_MODE_STRICT 0
#endif
#ifndef SECCOMP_SET_MODE_FILTER
#define SECCOMP_SET_MODE_FILTER 1
#endif
#ifndef SECCOMP_GET_ACTION_AVAIL
#define SECCOMP_GET_ACTION_AVAIL 2
#endif
#ifndef SECCOMP_GET_NOTIF_SIZES
#define SECCOMP_GET_NOTIF_SIZES 3
#endif
/* flags for the seccomp() syscall */
#ifndef SECCOMP_FILTER_FLAG_TSYNC
#define SECCOMP_FILTER_FLAG_TSYNC (1UL << 0)
#endif
#ifndef SECCOMP_FILTER_FLAG_LOG
#define SECCOMP_FILTER_FLAG_LOG (1UL << 1)
#endif
#ifndef SECCOMP_FILTER_FLAG_SPEC_ALLOW
#define SECCOMP_FILTER_FLAG_SPEC_ALLOW (1UL << 2)
#endif
#ifndef SECCOMP_FILTER_FLAG_NEW_LISTENER
#define SECCOMP_FILTER_FLAG_NEW_LISTENER (1UL << 3)
#endif
#ifndef SECCOMP_FILTER_FLAG_TSYNC_ESRCH
#define SECCOMP_FILTER_FLAG_TSYNC_ESRCH (1UL << 4)
#endif
#ifndef SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV
#define SECCOMP_FILTER_FLAG_WAIT_KILLABLE_RECV (1UL << 5)
#endif
#ifndef SECCOMP_RET_LOG
#define SECCOMP_RET_LOG 0x7ffc0000U /* allow after logging */
#endif
/* SECCOMP_RET_ACTION_FULL was added in kernel v4.14. */
#ifndef SECCOMP_RET_ACTION_FULL
#define SECCOMP_RET_ACTION_FULL 0xffff0000U
#endif
/* SECCOMP_RET_LOG was added in kernel v4.14. */
#ifndef SECCOMP_RET_LOG
#define SECCOMP_RET_LOG 0x7fc00000U
#endif
/* SECCOMP_RET_USER_NOTIF was added in kernel v5.0. */
#ifndef SECCOMP_RET_USER_NOTIF
#define SECCOMP_RET_USER_NOTIF 0x7fc00000U
struct seccomp_notif_sizes {
__u16 seccomp_notif;
__u16 seccomp_notif_resp;
__u16 seccomp_data;
};
struct seccomp_notif {
__u64 id;
__u32 pid;
__u32 flags;
struct seccomp_data data;
};
struct seccomp_notif_resp {
__u64 id;
__s64 val;
__s32 error;
__u32 flags;
};
#define SECCOMP_IOC_MAGIC '!'
#define SECCOMP_IO(nr) _IO(SECCOMP_IOC_MAGIC, nr)
#define SECCOMP_IOR(nr, type) _IOR(SECCOMP_IOC_MAGIC, nr, type)
#define SECCOMP_IOW(nr, type) _IOW(SECCOMP_IOC_MAGIC, nr, type)
#define SECCOMP_IOWR(nr, type) _IOWR(SECCOMP_IOC_MAGIC, nr, type)
/* flags for seccomp notification fd ioctl */
#define SECCOMP_IOCTL_NOTIF_RECV SECCOMP_IOWR(0, struct seccomp_notif)
#define SECCOMP_IOCTL_NOTIF_SEND SECCOMP_IOWR(1, \
struct seccomp_notif_resp)
#define SECCOMP_IOCTL_NOTIF_ID_VALID SECCOMP_IOW(2, __u64)
#endif /* SECCOMP_RET_USER_NOTIF */
/* non-public ioctl number for backwards compat (see system.c) */
#define SECCOMP_IOCTL_NOTIF_ID_VALID_WRONG_DIR SECCOMP_IOR(2, __u64)
void sys_reset_state(void);
int sys_chk_seccomp_syscall(void);
void sys_set_seccomp_syscall(bool enable);
int sys_chk_seccomp_action(uint32_t action);
void sys_set_seccomp_action(uint32_t action, bool enable);
int sys_chk_seccomp_flag(int flag);
void sys_set_seccomp_flag(int flag, bool enable);
int sys_filter_load(struct db_filter_col *col, bool rawrc);
int sys_notify_fd(void);
int sys_notify_alloc(struct seccomp_notif **req,
struct seccomp_notif_resp **resp);
int sys_notify_receive(int fd, struct seccomp_notif *req);
int sys_notify_respond(int fd, struct seccomp_notif_resp *resp);
int sys_notify_id_valid(int fd, uint64_t id);
#endif
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