text: /**
   * 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;
  
  #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 defintions */
  #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_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_IOR(2, __u64)
  #endif /* SECCOMP_RET_USER_NOTIF */
  
  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);
  
  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
  