/*
 * Copyright (c) 2021 Albert S. <mail at quitesimple dot org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef EXILE_H
#define EXILE_H

#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif

#include <sched.h>
#include <stdio.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/random.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/mman.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <linux/limits.h>
#include <linux/filter.h>
#include <linux/seccomp.h>
#include <linux/version.h>
#include <linux/audit.h>
#include <linux/capability.h>
#include <stddef.h>
#include <inttypes.h>
#include <asm/unistd.h>

#define capget(hdrp,datap) syscall(__NR_capget,hdrp,datap)
#define capset(hdrp,datap) syscall(__NR_capset,hdrp,datap)


#ifndef HAVE_LANDLOCK
	#if LINUX_VERSION_CODE >= KERNEL_VERSION(5,13,0)
		/* TODO: Hopefully a fair assumption. But we need to runtime checks */
		#define HAVE_LANDLOCK 1
	#endif
#endif
#if HAVE_LANDLOCK == 1
	#include <linux/landlock.h>
	#if LANDLOCK_CREATE_RULESET_VERSION != (1U << 0)
		#error "This landlock ABI version is not supported by exile.h (yet)"
	#endif
#endif


#if defined(__x86_64__)
#define SECCOMP_AUDIT_ARCH AUDIT_ARCH_X86_64
#else
#error Seccomp support has not been tested for exile.h for this platform yet
#endif

#define EXILE_UNSHARE_NETWORK 1<<1
#define EXILE_UNSHARE_USER 1<<2
#define EXILE_UNSHARE_MOUNT 1<<3

#ifndef EXILE_LOG_ERROR
#define EXILE_LOG_ERROR(...) fprintf(stderr, __VA_ARGS__)
#endif

#ifndef EXILE_TEMP_DIR
#define EXILE_TEMP_DIR "/tmp"
#endif

#define EXILE_SYS(x) __NR_##x

/* Allow all read-effect operations on the path */
#define EXILE_FS_ALLOW_ALL_READ 1<<0
/* Allow all write-effect operations on the path, such as normal writes, creation/deletion of files */
#define EXILE_FS_ALLOW_ALL_WRITE (1<<1)
#define EXILE_FS_ALLOW_EXEC 1<<2
#define EXILE_FS_ALLOW_DEV 1<<3
#define EXILE_FS_ALLOW_SETUID 1<<4

//don't mount recursive
#define EXILE_MOUNT_NOT_REC 1<<5

/* Fine-granular approach available with landlock */
#if HAVE_LANDLOCK == 1
#define EXILE_FS_ALLOW_REMOVE_DIR		(1 << 7)
#define EXILE_FS_ALLOW_REMOVE_FILE		(1 << 8)
#define EXILE_FS_ALLOW_MAKE_CHAR		(1 << 9)
#define EXILE_FS_ALLOW_MAKE_DIR			(1 << 10)
#define EXILE_FS_ALLOW_MAKE_REG			(1 << 11)
#define EXILE_FS_ALLOW_MAKE_SOCK		(1 << 12)
#define EXILE_FS_ALLOW_MAKE_FIFO		(1 << 13)
#define EXILE_FS_ALLOW_MAKE_BLOCK		(1 << 14)
#define EXILE_FS_ALLOW_MAKE_SYM			(1 << 15)
#define EXILE_FS_ALLOW_WRITE_FILE 		(1 << 16)
#define EXILE_FS_ALLOW_READ_DIR			(1 << 17)
#define EXILE_FS_ALLOW_REMOVE 			(1 << 18)

#ifndef landlock_create_ruleset
static inline int landlock_create_ruleset(
		const struct landlock_ruleset_attr *const attr,
		const size_t size, const __u32 flags)
{
	return syscall(__NR_landlock_create_ruleset, attr, size, flags);
}
#endif

#ifndef landlock_add_rule
static inline int landlock_add_rule(const int ruleset_fd,
		const enum landlock_rule_type rule_type,
		const void *const rule_attr, const __u32 flags)
{
	return syscall(__NR_landlock_add_rule, ruleset_fd, rule_type,
			rule_attr, flags);
}
#endif

#ifndef landlock_restrict_self
static inline int landlock_restrict_self(const int ruleset_fd,
		const __u32 flags)
{
	return syscall(__NR_landlock_restrict_self, ruleset_fd, flags);
}
#endif
#endif

#if defined(__x86_64__)
#ifndef __NR_pkey_mprotect
#define __NR_pkey_mprotect 329
#endif
#ifndef __NR_pkey_alloc
#define __NR_pkey_alloc 330
#endif
#ifndef __NR_pkey_free
#define __NR_pkey_free 331
#endif
#ifndef __NR_statx
#define __NR_statx 332
#endif
#ifndef __NR_io_pgetevents
#define __NR_io_pgetevents 333
#endif
#ifndef __NR_rseq
#define __NR_rseq 334
#endif
#ifndef __NR_pidfd_send_signal
#define __NR_pidfd_send_signal 424
#endif
#ifndef __NR_io_uring_setup
#define __NR_io_uring_setup 425
#endif
#ifndef __NR_io_uring_enter
#define __NR_io_uring_enter 426
#endif
#ifndef __NR_io_uring_register
#define __NR_io_uring_register 427
#endif
#ifndef __NR_open_tree
#define __NR_open_tree 428
#endif
#ifndef __NR_move_mount
#define __NR_move_mount 429
#endif
#ifndef __NR_fsopen
#define __NR_fsopen 430
#endif
#ifndef __NR_fsconfig
#define __NR_fsconfig 431
#endif
#ifndef __NR_fsmount
#define __NR_fsmount 432
#endif
#ifndef __NR_fspick
#define __NR_fspick 433
#endif
#ifndef __NR_pidfd_open
#define __NR_pidfd_open 434
#endif
#ifndef __NR_clone3
#define __NR_clone3 435
#endif
#ifndef __NR_close_range
#define __NR_close_range 436
#endif
#ifndef __NR_openat2
#define __NR_openat2 437
#endif
#ifndef __NR_pidfd_getfd
#define __NR_pidfd_getfd 438
#endif
#ifndef __NR_faccessat2
#define __NR_faccessat2 439
#endif
#ifndef __NR_process_madvise
#define __NR_process_madvise 440
#endif
#ifndef __NR_epoll_pwait2
#define __NR_epoll_pwait2 441
#endif
#ifndef __NR_mount_setattr
#define __NR_mount_setattr 442
#endif
#ifndef __NR_quotactl_fd
#define __NR_quotactl_fd 443
#endif
#ifndef __NR_landlock_create_ruleset
#define __NR_landlock_create_ruleset 444
#endif
#ifndef __NR_landlock_add_rule
#define __NR_landlock_add_rule 445
#endif
#ifndef __NR_landlock_restrict_self
#define __NR_landlock_restrict_self 446
#endif
#ifndef __NR_memfd_secret
#define __NR_memfd_secret 447
#endif
#ifndef __NR_process_mrelease
#define __NR_process_mrelease 448
#endif
#endif

struct syscall_pledge_map
{
	long syscall;
	uint64_t pledgemask;
};

struct exile_path_policy
{
	const char *path;
	unsigned int policy;
	struct exile_path_policy *next;
};

/* Special values */
#define EXILE_SYSCALL_MATCH_ALL -1
/* exit the bpf filter, not matching policy. Go to the next syscall (or the default action, if none left to check) */
#define EXILE_SYSCALL_EXIT_BPF_NO_MATCH 255
/* exit the bpf filter, go directly to the action for the syscall (skip all other args checks) */
#define EXILE_SYSCALL_EXIT_BPF_RETURN 254

#define EXILE_SYSCALL_ALLOW 1
#define EXILE_SYSCALL_DENY_KILL_PROCESS 2
#define EXILE_SYSCALL_DENY_RET_ERROR 3

#define EXILE_BPF_NOP \
BPF_STMT(BPF_JMP+BPF_JA,0)

#define EXILE_BPF_LOAD_SECCOMP_ARG(nr) \
BPF_STMT(BPF_LD+BPF_W+BPF_ABS, (offsetof(struct seccomp_data, args[nr])))

#define EXILE_BPF_CMP_EQ(val,t,f) \
BPF_JUMP(BPF_JMP+BPF_JEQ+BPF_K, val, t, f)

#define EXILE_BPF_CMP_SET(val,t,f) \
BPF_JUMP(BPF_JMP+BPF_JSET+BPF_K, val, t, f)

/* Immediatly go to the syscall action, do not process any other arg filters */
#define EXILE_BPF_MATCH(argval) \
	EXILE_BPF_CMP_EQ(argval,  EXILE_SYSCALL_EXIT_BPF_RETURN, 0)

#define EXILE_BPF_MATCH_SET(argval) \
	EXILE_BPF_CMP_SET(argval, EXILE_SYSCALL_EXIT_BPF_RETURN, 0)

/* Immediatly go beyond the syscall action, do not process any other arg filters. What to do with this syscall
is thus up to the default policy  */
#define EXILE_BPF_NO_MATCH(argval) \
	EXILE_BPF_CMP_EQ(argval, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)

#define EXILE_BPF_NO_MATCH_SET(argval) \
	EXILE_BPF_CMP_SET(argval, EXILE_SYSCALL_EXIT_BPF_NO_MATCH, 0)


/* Pledge definitions */
#define EXILE_SYSCALL_PLEDGE_CHOWN ((uint64_t)1<<1)
#define EXILE_SYSCALL_PLEDGE_CLONE ((uint64_t)1<<2)
#define EXILE_SYSCALL_PLEDGE_CPATH ((uint64_t)1<<3)
#define EXILE_SYSCALL_PLEDGE_DPATH ((uint64_t)1<<4)
#define EXILE_SYSCALL_PLEDGE_EXEC ((uint64_t)1<<5)
#define EXILE_SYSCALL_PLEDGE_FATTR ((uint64_t)1<<6)
#define EXILE_SYSCALL_PLEDGE_FSNOTIFY ((uint64_t)1<<7)
#define EXILE_SYSCALL_PLEDGE_ID ((uint64_t)1<<8)
#define EXILE_SYSCALL_PLEDGE_INET ((uint64_t)1<<9)
#define EXILE_SYSCALL_PLEDGE_IOCTL ((uint64_t)1<<10)
#define EXILE_SYSCALL_PLEDGE_PRCTL ((uint64_t)1<<11)
#define EXILE_SYSCALL_PLEDGE_PROC ((uint64_t)1<<12)
#define EXILE_SYSCALL_PLEDGE_PROT_EXEC ((uint64_t)1<<13)
#define EXILE_SYSCALL_PLEDGE_RPATH ((uint64_t)1<<14)
#define EXILE_SYSCALL_PLEDGE_SCHED ((uint64_t)1<<15)
#define EXILE_SYSCALL_PLEDGE_SECCOMP_INSTALL ((uint64_t)1<<16)
#define EXILE_SYSCALL_PLEDGE_SHM ((uint64_t)1<<17)
#define EXILE_SYSCALL_PLEDGE_STDIO ((uint64_t)1<<18)
#define EXILE_SYSCALL_PLEDGE_THREAD ((uint64_t)1<<19)
#define EXILE_SYSCALL_PLEDGE_UNIX ((uint64_t)1<<20)
#define EXILE_SYSCALL_PLEDGE_WPATH ((uint64_t)1<<21)

#define EXILE_SYSCALL_PLEDGE_DENY_ERROR ((uint64_t)1<<63)


#define EXILE_ARGFILTERS_COUNT 60
struct exile_syscall_policy
{
	struct sock_filter argfilters[EXILE_ARGFILTERS_COUNT];
	size_t argfilterscount;
	long syscall;
	unsigned int policy;
	struct exile_syscall_policy *next;
};

/* Policy tells exile what to do */
struct exile_policy
{
	int drop_caps;
	int preserve_cwd;
	int not_dumpable;
	int no_new_privs;
	int no_fs;
	int no_new_fds;
	int namespace_options;
	int disable_syscall_filter;
	/* Bind mounts all paths in path_policies into the chroot and applies
	 non-landlock policies */
	int mount_path_policies_to_chroot;
	char chroot_target_path[PATH_MAX];
	const char *chdir_path;

	uint64_t pledge_promises;

	/* Do not manually add policies here, use exile_append_path_polic*() */
	struct exile_path_policy *path_policies;
	struct exile_path_policy **path_policies_tail;

	/* Do not manually add policies here, use exile_append_syscall_policy() */
	struct exile_syscall_policy *syscall_policies;
	struct exile_syscall_policy **syscall_policies_tail;

};


static struct syscall_pledge_map exile_pledge_map[] =
{
	{EXILE_SYS(read), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(write), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(open), EXILE_SYSCALL_PLEDGE_RPATH|EXILE_SYSCALL_PLEDGE_WPATH},
	{EXILE_SYS(close), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(stat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(fstat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(lstat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(poll), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(lseek), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mmap), EXILE_SYSCALL_PLEDGE_STDIO|EXILE_SYSCALL_PLEDGE_PROT_EXEC},
	{EXILE_SYS(mprotect), EXILE_SYSCALL_PLEDGE_STDIO|EXILE_SYSCALL_PLEDGE_PROT_EXEC},
	{EXILE_SYS(munmap), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(brk), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigaction), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigprocmask), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigreturn), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(ioctl), EXILE_SYSCALL_PLEDGE_STDIO|EXILE_SYSCALL_PLEDGE_IOCTL},
	{EXILE_SYS(pread64), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(pwrite64), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(readv), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(writev), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(access), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(pipe), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(select), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(sched_yield), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mremap), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(msync), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mincore), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(madvise), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(shmget), EXILE_SYSCALL_PLEDGE_SHM},
	{EXILE_SYS(shmat), EXILE_SYSCALL_PLEDGE_SHM},
	{EXILE_SYS(shmctl), EXILE_SYSCALL_PLEDGE_SHM},
	{EXILE_SYS(dup), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(dup2), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(pause), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(nanosleep), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getitimer), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(alarm), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setitimer), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getpid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(sendfile), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(socket), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(connect), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(accept), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(sendto), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(recvfrom), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(sendmsg), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(recvmsg), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(shutdown), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(bind), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(listen), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(getsockname), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(getpeername), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(socketpair), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setsockopt), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(getsockopt), EXILE_SYSCALL_PLEDGE_INET|EXILE_SYSCALL_PLEDGE_UNIX},
	{EXILE_SYS(clone), EXILE_SYSCALL_PLEDGE_CLONE|EXILE_SYSCALL_PLEDGE_THREAD},
	{EXILE_SYS(fork), EXILE_SYSCALL_PLEDGE_CLONE},
	{EXILE_SYS(vfork), EXILE_SYSCALL_PLEDGE_CLONE},
	{EXILE_SYS(execve), EXILE_SYSCALL_PLEDGE_EXEC},
	{EXILE_SYS(exit), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(wait4), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(kill), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(uname), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(semget), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(semop), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(semctl), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(shmdt), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(msgget), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(msgsnd), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(msgrcv), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(msgctl), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(fcntl), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(flock), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(fsync), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(fdatasync), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(truncate), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(ftruncate), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getdents), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(getcwd), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(chdir), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(fchdir), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(rename), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(mkdir), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(rmdir), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(creat), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(link), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(unlink), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(symlink), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(readlink), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(chmod), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(fchmod), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(chown), EXILE_SYSCALL_PLEDGE_CHOWN},
	{EXILE_SYS(fchown), EXILE_SYSCALL_PLEDGE_CHOWN},
	{EXILE_SYS(lchown), EXILE_SYSCALL_PLEDGE_CHOWN},
	{EXILE_SYS(umask), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(gettimeofday), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getrlimit), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getrusage), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(sysinfo), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(times), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getuid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getgid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setuid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(setgid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(geteuid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getegid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setpgid), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(getppid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getpgrp), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setsid), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(setreuid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(setregid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(getgroups), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setgroups), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(setresuid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(getresuid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setresgid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(getresgid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getpgid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setfsuid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(setfsgid), EXILE_SYSCALL_PLEDGE_ID},
	{EXILE_SYS(getsid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(capget), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigpending), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigtimedwait), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigqueueinfo), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(rt_sigsuspend), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(utime), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(mknod), EXILE_SYSCALL_PLEDGE_DPATH},
	{EXILE_SYS(uselib), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(ustat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(statfs), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(fstatfs), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(getpriority), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(setpriority), EXILE_SYSCALL_PLEDGE_SCHED|EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(sched_setparam), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_getparam), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_setscheduler), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_getscheduler), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_get_priority_max), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_get_priority_min), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_rr_get_interval), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(mlock), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(munlock), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mlockall), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(munlockall), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(vhangup), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(prctl), EXILE_SYSCALL_PLEDGE_STDIO|EXILE_SYSCALL_PLEDGE_PRCTL|EXILE_SYSCALL_PLEDGE_SECCOMP_INSTALL},
	{EXILE_SYS(setrlimit), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(sync), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(gettid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(readahead), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(setxattr), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(lsetxattr), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(fsetxattr), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(getxattr), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(lgetxattr), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(fgetxattr), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(listxattr), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(llistxattr), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(flistxattr), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(removexattr), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(lremovexattr), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(fremovexattr), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(tkill), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(time), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(futex), EXILE_SYSCALL_PLEDGE_THREAD},
	{EXILE_SYS(sched_getaffinity), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(set_thread_area), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(get_thread_area), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(lookup_dcookie), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_create), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_ctl_old), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_wait_old), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(remap_file_pages), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getdents64), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(set_tid_address), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(semtimedop), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(fadvise64), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timer_create), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timer_settime), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timer_gettime), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timer_getoverrun), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timer_delete), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(clock_gettime), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(clock_getres), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(clock_nanosleep), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(exit_group), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_wait), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_ctl), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(tgkill), EXILE_SYSCALL_PLEDGE_PROC},
	{EXILE_SYS(utimes), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(mbind), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(get_mempolicy), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mq_open), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mq_unlink), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mq_timedsend), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mq_timedreceive), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mq_notify), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(mq_getsetattr), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(waitid), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(inotify_init), EXILE_SYSCALL_PLEDGE_FSNOTIFY},
	{EXILE_SYS(inotify_add_watch), EXILE_SYSCALL_PLEDGE_FSNOTIFY},
	{EXILE_SYS(inotify_rm_watch), EXILE_SYSCALL_PLEDGE_FSNOTIFY},
	{EXILE_SYS(openat), EXILE_SYSCALL_PLEDGE_RPATH|EXILE_SYSCALL_PLEDGE_WPATH},
	{EXILE_SYS(mkdirat), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(mknodat), EXILE_SYSCALL_PLEDGE_DPATH},
	{EXILE_SYS(fchownat), EXILE_SYSCALL_PLEDGE_CHOWN},
	{EXILE_SYS(futimesat), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(newfstatat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(unlinkat), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(renameat), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(linkat), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(symlinkat), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(readlinkat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(fchmodat), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(faccessat), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(pselect6), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(ppoll), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(set_robust_list), EXILE_SYSCALL_PLEDGE_THREAD},
	{EXILE_SYS(get_robust_list), EXILE_SYSCALL_PLEDGE_THREAD},
	{EXILE_SYS(splice), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(tee), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(sync_file_range), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(vmsplice), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(move_pages), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(utimensat), EXILE_SYSCALL_PLEDGE_FATTR},
	{EXILE_SYS(epoll_pwait), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(signalfd), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timerfd_create), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(eventfd), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(fallocate), EXILE_SYSCALL_PLEDGE_WPATH|EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(timerfd_settime), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(timerfd_gettime), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(accept4), EXILE_SYSCALL_PLEDGE_UNIX|EXILE_SYSCALL_PLEDGE_INET},
	{EXILE_SYS(signalfd4), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(eventfd2), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_create1), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(dup3), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(pipe2), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(inotify_init1), EXILE_SYSCALL_PLEDGE_FSNOTIFY},
	{EXILE_SYS(preadv), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(pwritev), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(recvmmsg), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(fanotify_init), EXILE_SYSCALL_PLEDGE_FSNOTIFY},
	{EXILE_SYS(fanotify_mark), EXILE_SYSCALL_PLEDGE_FSNOTIFY},
	{EXILE_SYS(open_by_handle_at), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(sendmmsg), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(getcpu), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(sched_setattr), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(sched_getattr), EXILE_SYSCALL_PLEDGE_SCHED},
	{EXILE_SYS(renameat2), EXILE_SYSCALL_PLEDGE_CPATH},
	{EXILE_SYS(getrandom), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(execveat), EXILE_SYSCALL_PLEDGE_EXEC},
	{EXILE_SYS(mlock2), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(copy_file_range), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(statx), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(clone3), EXILE_SYSCALL_PLEDGE_CLONE},
	{EXILE_SYS(close_range), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(openat2), EXILE_SYSCALL_PLEDGE_RPATH|EXILE_SYSCALL_PLEDGE_WPATH},
	{EXILE_SYS(faccessat2), EXILE_SYSCALL_PLEDGE_RPATH},
	{EXILE_SYS(process_madvise), EXILE_SYSCALL_PLEDGE_STDIO},
	{EXILE_SYS(epoll_pwait2), EXILE_SYSCALL_PLEDGE_STDIO}
};


static int is_valid_syscall_policy(unsigned int policy)
{
	return policy == EXILE_SYSCALL_ALLOW || policy == EXILE_SYSCALL_DENY_RET_ERROR || policy == EXILE_SYSCALL_DENY_KILL_PROCESS;
}

int exile_append_syscall_policy(struct exile_policy *exile_policy, long syscall, unsigned int syscall_policy, struct sock_filter *argfilters, size_t n)
{
	struct exile_syscall_policy *newpolicy = (struct exile_syscall_policy *) calloc(1, sizeof(struct exile_syscall_policy));
	if(newpolicy == NULL)
	{
		EXILE_LOG_ERROR("Failed to allocate memory for syscall policy\n");
		return -1;
	}
	newpolicy->policy = syscall_policy;
	newpolicy->syscall = syscall;
	newpolicy->argfilterscount = n;
	if(n > EXILE_ARGFILTERS_COUNT)
	{
		EXILE_LOG_ERROR("Too many argfilters supplied\n");
		return -1;
	}
	for(size_t i = 0; i < n; i++)
	{
		newpolicy->argfilters[i] = argfilters[i];
	}
	newpolicy->next = NULL;

	*(exile_policy->syscall_policies_tail) = newpolicy;
	exile_policy->syscall_policies_tail = &(newpolicy->next);

	exile_policy->disable_syscall_filter = 0;
	return 0;
}


int exile_append_syscall_default_policy(struct exile_policy *exile_policy, unsigned int default_policy)
{
	return exile_append_syscall_policy(exile_policy, EXILE_SYSCALL_MATCH_ALL, default_policy, NULL, 0);
}

/* Returns, for the specific syscall, the correct sock_filter struct for the provided pledge_promises

	Returns: 0 if none copied, otherwise the number of entries in "filter".
 */

static int get_pledge_argfilter(long syscall, uint64_t pledge_promises, struct sock_filter *filter , int *policy)
{

	/* How to read this:
	 * Keep in mind our default action is do deny, unless it's a syscall from an pledge promise. Then it will be
	 * accepted if the argument values are good (if we care about them at all).
	 * EXILE_BPF_MATCH() means the argument value is good, and the syscall can be accepted
	 * EXILE_BPF_NO_MATCH() means the syscall won't be allowed because the value is illegal
	 */
	struct sock_filter mmap_no_exec[] = {
		EXILE_BPF_LOAD_SECCOMP_ARG(2),
		EXILE_BPF_NO_MATCH(PROT_EXEC)
	};

	struct sock_filter ioctl_default[] = {
			EXILE_BPF_LOAD_SECCOMP_ARG(1),
			EXILE_BPF_MATCH(FIONREAD),
			EXILE_BPF_MATCH(FIONBIO),
			EXILE_BPF_MATCH(FIOCLEX),
			EXILE_BPF_CMP_EQ(FIONCLEX, EXILE_SYSCALL_EXIT_BPF_RETURN, EXILE_SYSCALL_EXIT_BPF_NO_MATCH)
	};

	/* open() and friends with read-only flags */
	struct sock_filter open_rdonly[] = {
		EXILE_BPF_LOAD_SECCOMP_ARG(1),
		EXILE_BPF_NO_MATCH_SET(O_CREAT),
		EXILE_BPF_NO_MATCH_SET(O_TMPFILE),
		EXILE_BPF_NO_MATCH_SET(O_WRONLY),
		EXILE_BPF_NO_MATCH_SET(O_RDWR),
		EXILE_BPF_NO_MATCH_SET(O_APPEND),
	};

	struct sock_filter socket_filter[4] = {
		EXILE_BPF_LOAD_SECCOMP_ARG(0),
		EXILE_BPF_NOP,
		EXILE_BPF_NOP,
		EXILE_BPF_NOP
	};

	struct sock_filter setsockopt_filter[] = {
		EXILE_BPF_LOAD_SECCOMP_ARG(2),
		EXILE_BPF_NO_MATCH(SO_DEBUG),
		EXILE_BPF_NO_MATCH(SO_SNDBUFFORCE)
	};


	struct sock_filter clone_filter[] = {
		/* It's the first argument for x86_64 */
		EXILE_BPF_LOAD_SECCOMP_ARG(0),
		EXILE_BPF_NO_MATCH_SET(CLONE_VM),
		EXILE_BPF_NO_MATCH_SET(CLONE_THREAD),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWCGROUP),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWIPC),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWNET),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWNS),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWPID),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWUSER),
		EXILE_BPF_NO_MATCH_SET(CLONE_NEWUTS),
	};

	struct sock_filter prctl_default[] ={
		EXILE_BPF_LOAD_SECCOMP_ARG(0),
		EXILE_BPF_MATCH(PR_SET_NO_NEW_PRIVS),
		EXILE_BPF_MATCH(PR_GET_NO_NEW_PRIVS),
		EXILE_BPF_MATCH(PR_GET_NAME),
		EXILE_BPF_MATCH(PR_SET_NAME),
		EXILE_BPF_CMP_EQ(PR_CAPBSET_READ, EXILE_SYSCALL_EXIT_BPF_RETURN, EXILE_SYSCALL_EXIT_BPF_NO_MATCH),
	};

	*policy = EXILE_SYSCALL_ALLOW;
	int result = 0;
	int current_filter_index = 1;
	switch(syscall)
	{
		case EXILE_SYS(mmap):
		case EXILE_SYS(mprotect):
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_PROT_EXEC)
			{
				/* If prot exec is allowed, there is no need to filter anything here */
				result = 0;
				break;
			}
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_STDIO)
			{
				result = sizeof(mmap_no_exec)/sizeof(mmap_no_exec[0]);
				memcpy(filter, mmap_no_exec, sizeof(mmap_no_exec));
			}
			break;
		case EXILE_SYS(ioctl):
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_IOCTL)
			{
				result = 0;
				break;
			}
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_STDIO)
			{
				result = sizeof(ioctl_default)/sizeof(ioctl_default[0]);
				memcpy(filter, ioctl_default, sizeof(ioctl_default));
			}
			break;
		case EXILE_SYS(open):
		case EXILE_SYS(openat):
		case EXILE_SYS(open_by_handle_at):
			/* TODO: This is still a mess with all those combinations.
			 We should think of something better */
			if(syscall == EXILE_SYS(openat) || syscall ==  EXILE_SYS(open_by_handle_at))
			{
				/* for openat, it's the third arg */
				open_rdonly[0].k = offsetof(struct seccomp_data, args[2]);
			}
			/* The combination of those three implies no filtering of open args */
			if((pledge_promises & (EXILE_SYSCALL_PLEDGE_CPATH|EXILE_SYSCALL_PLEDGE_RPATH|EXILE_SYSCALL_PLEDGE_WPATH)) == (EXILE_SYSCALL_PLEDGE_CPATH|EXILE_SYSCALL_PLEDGE_RPATH|EXILE_SYSCALL_PLEDGE_WPATH))
			{
				result = 0;
				break;
			}
			/* If cpath is legal, don't filter O_CREAT */
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_CPATH)
			{
				open_rdonly[1] = (struct sock_filter) EXILE_BPF_NOP;
			}
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_WPATH)
			{
				open_rdonly[2] = (struct sock_filter) EXILE_BPF_NOP;
				open_rdonly[3] = (struct sock_filter) EXILE_BPF_NOP;
				open_rdonly[4] = (struct sock_filter) EXILE_BPF_NOP;
				open_rdonly[5] = (struct sock_filter) EXILE_BPF_NOP;
			}
			result = sizeof(open_rdonly)/sizeof(open_rdonly[0]);
			memcpy(filter, open_rdonly, sizeof(open_rdonly));
			break;
		case EXILE_SYS(openat2):
			result = 0;
			*policy = EXILE_SYSCALL_DENY_RET_ERROR;
			break;
		case EXILE_SYS(socket):
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_UNIX)
			{
				socket_filter[current_filter_index] = (struct sock_filter) EXILE_BPF_MATCH(AF_UNIX);
				++current_filter_index;
			}
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_INET)
			{
				socket_filter[current_filter_index] = (struct sock_filter) EXILE_BPF_MATCH(AF_INET);
				++current_filter_index;
				socket_filter[current_filter_index] = (struct sock_filter) EXILE_BPF_MATCH(AF_INET6);
				++current_filter_index;
			}
			socket_filter[current_filter_index-1].jf = EXILE_SYSCALL_EXIT_BPF_NO_MATCH;
			result = current_filter_index;
			memcpy(filter, socket_filter, result * sizeof(struct sock_filter));
			break;
		case EXILE_SYS(setsockopt):
			result = sizeof(setsockopt_filter)/sizeof(setsockopt_filter[0]);
			memcpy(filter, setsockopt_filter, sizeof(setsockopt_filter));
			break;
		case EXILE_SYS(clone):
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_CLONE)
			{
				result = 0;
				break;
			}
			result = sizeof(clone_filter)/sizeof(clone_filter[0]);
			memcpy(filter, clone_filter, sizeof(clone_filter));
			break;
		case EXILE_SYS(clone3):
			if((pledge_promises & EXILE_SYSCALL_PLEDGE_CLONE) == 0)
			{
				result = 0;
				*policy = EXILE_SYSCALL_DENY_RET_ERROR;
			}
			break;
		case EXILE_SYS(prctl):
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_PRCTL)
			{
				result = 0;
				break;
			}
			if(pledge_promises & EXILE_SYSCALL_PLEDGE_SECCOMP_INSTALL)
			{
				prctl_default[3] = (struct sock_filter) EXILE_BPF_MATCH(PR_SET_SECCOMP);
			}
			result = sizeof(prctl_default)/sizeof(prctl_default[0]);
			memcpy(filter, prctl_default, sizeof(prctl_default));
			break;
	}
	return result;
}

int exile_append_pledge_promises(struct exile_policy *policy, uint64_t pledge_promises)
{
	for(unsigned int i = 0; i < sizeof(exile_pledge_map)/sizeof(exile_pledge_map[0]); i++)
	{
		struct syscall_pledge_map *current_map = &exile_pledge_map[i];
		if(current_map->pledgemask & pledge_promises)
		{
			struct sock_filter filter[EXILE_ARGFILTERS_COUNT];
			long syscall = current_map->syscall;
			int syscall_policy = EXILE_SYSCALL_ALLOW;
			int argfilters = get_pledge_argfilter(syscall, pledge_promises, filter, &syscall_policy);
			int ret = exile_append_syscall_policy(policy, syscall, syscall_policy, filter, argfilters);
			if(ret != 0)
			{
				EXILE_LOG_ERROR("Failed adding syscall policy from pledge while processing %li\n", syscall);
				return ret;
			}

		}
	}
	int pledge_policy = (pledge_promises & EXILE_SYSCALL_PLEDGE_DENY_ERROR) ? EXILE_SYSCALL_DENY_RET_ERROR : EXILE_SYSCALL_DENY_KILL_PROCESS;
	return exile_append_syscall_default_policy(policy, pledge_policy);
}

/* Creates an empty policy struct without opinionated defaults.
 *
 * Must be freed using exile_free_policy()
 * @returns: empty policy
 */
struct exile_policy *exile_create_policy()
{
	struct exile_policy *result = (struct exile_policy *) calloc(1, sizeof(struct exile_policy));
	if(result == NULL)
	{
		EXILE_LOG_ERROR("Failed to allocate memory for policy\n");
		return NULL;
	}
	result->path_policies_tail = &(result->path_policies);
	result->syscall_policies_tail = &(result->syscall_policies);
	return result;
}

/* Creates the default policy
 * Must be freed using exile_free_policy()
 *
 * @returns: default policy
 */
struct exile_policy *exile_init_policy()
{
	struct exile_policy *result = exile_create_policy();
	if(result == NULL)
	{
		return NULL;
	}
	result->drop_caps = 1;
	result->not_dumpable = 1;
	result->no_new_privs = 1;
	result->namespace_options = EXILE_UNSHARE_MOUNT | EXILE_UNSHARE_USER;
	return result;
}

/* Appends path policies to the exile_policy object
 * The last paramater must be NULL
 *
 * This function does not copy parameters. All passed paths
 * MUST NOT be freed until exile_enable_policy() is called!
 *
 * @returns: 0 on success, -1 on failure */
int exile_append_path_policies(struct exile_policy *exile_policy, unsigned int path_policy, ...)
{
	va_list args;
	const char *path;
	va_start(args, path_policy);

	path = va_arg(args, char*);
	while(path != NULL)
	{
		struct exile_path_policy *newpolicy = (struct exile_path_policy *) calloc(1, sizeof(struct exile_path_policy));
		if(newpolicy == NULL)
		{
			EXILE_LOG_ERROR("Failed to allocate memory for path policy\n");
			return -1;
		}
		newpolicy->path = path;
		newpolicy->policy = path_policy;
		newpolicy->next = NULL;

		*(exile_policy->path_policies_tail) = newpolicy;
		exile_policy->path_policies_tail = &(newpolicy->next);
		path = va_arg(args, char*);
	}

	va_end(args);

	return 0;
}

int exile_append_path_policy(struct exile_policy *exile_policy, unsigned int path_policy, const char *path)
{
	return exile_append_path_policies(exile_policy, path_policy, path, NULL);
}



/*
 * Fills buffer with random characters a-z.
 * The string will be null terminated.
 *
 * @returns: number of written chars (excluding terminating null byte) on success
 */
int random_string(char *buffer, size_t buffer_length)
{
	int r = getrandom(buffer, buffer_length-1, GRND_NONBLOCK);
	if(r != -1 && (size_t) r == buffer_length-1)
	{
		int i = 0;
		while(i < r)
		{
			buffer[i] = 'a' + ((unsigned int)buffer[i] % 26);
			++i;
		}
		buffer[buffer_length-1] = '\0';
		return i;
	}
	return 0;
}


/* Creates a directory and all necessary parent directories
 *
 * @returns: 0 on success, -ERRNO on failure
 * */
static int mkdir_structure(const char *p, mode_t mode)
{
	char path[PATH_MAX] = { 0 };
	int res = snprintf(path, sizeof(path), "%s/", p);
	if(res < 0)
	{
		EXILE_LOG_ERROR("exile: mkdir_strucutre: error during path concatination\n");
		return -EINVAL;
	}
	if(res >= PATH_MAX)
	{
		EXILE_LOG_ERROR("exile: mkdir_structure: path concatination truncated\n");
		return -EINVAL;
	}


	char *begin = path;
	char *end = begin+1;

	while(*end)
	{
		if(*end == '/')
		{
			*end = 0;
			if(mkdir(begin, mode) < 0)
			{
				if(errno == EEXIST)
				{
					//TODO: stat, test if it is a directory, if not, err
				}
				else
				{
					EXILE_LOG_ERROR("Failed to create directory for chroot: %s\n", begin);
					return -1;
				}
			}
			*end = '/';
			++end;
			while(*end == '/')
			{
				++end;
			}
		}
		else
		{
			++end;
		}
	}
	return 0;
}

/* @returns: argument for mount(2) flags */
static int get_policy_mount_flags(struct exile_path_policy *policy)
{
	int result = 0;

	if( (policy->policy & EXILE_FS_ALLOW_DEV) == 0)
	{
		result |= MS_NODEV;
	}

	if( (policy->policy & EXILE_FS_ALLOW_EXEC) == 0)
	{
		result |= MS_NOEXEC;
	}

	if( (policy->policy & EXILE_FS_ALLOW_SETUID) == 0)
	{
		result |= MS_NOSUID;
	}

	if( (policy->policy & EXILE_FS_ALLOW_ALL_WRITE) == 0)
	{
		result |= MS_RDONLY;
	}

	if( (policy->policy & EXILE_MOUNT_NOT_REC) == 0)
	{
		result |= MS_REC;
	}
	return result;
}

/* Helper to mount directories into the chroot path "chroot_target_path"
 * Paths will be created if necessary

 * @returns: 0 on sucess, -ERRNO on failure */
static int mount_to_chroot(const char *chroot_target_path, struct exile_path_policy *path_policy)
{
	while(path_policy != NULL)
	{

		char path_inside_chroot[PATH_MAX];
		int written = snprintf(path_inside_chroot, sizeof(path_inside_chroot), "%s/%s", chroot_target_path, path_policy->path);
		if(written < 0)
		{
			EXILE_LOG_ERROR("exile: mount_to_chroot: Error during path concatination\n");
			return -EINVAL;
		}
		if(written >= PATH_MAX)
		{
			EXILE_LOG_ERROR("exile: mount_to_chroot: path concatination truncated\n");
			return -EINVAL;
		}
		int ret = mkdir_structure(path_inside_chroot, 0700);
		if(ret < 0)
		{
			EXILE_LOG_ERROR("Error creating directory structure while mounting paths to chroot. %s\n", strerror(errno));
			return ret;
		}

		int mount_flags = get_policy_mount_flags(path_policy);

		//all we do is bind mounts
		mount_flags |= MS_BIND;


		if(path_policy->policy & EXILE_FS_ALLOW_ALL_READ || path_policy->policy & EXILE_FS_ALLOW_ALL_WRITE)
		{
			ret = mount(path_policy->path, path_inside_chroot,  NULL, mount_flags, NULL);
			if(ret < 0 )
			{
				EXILE_LOG_ERROR("Error: Failed to mount %s to %s: %s\n", path_policy->path, path_inside_chroot, strerror(errno));
				return ret;
			}

			//remount so noexec, readonly etc. take effect
			ret = mount(NULL, path_inside_chroot, NULL, mount_flags | MS_REMOUNT, NULL);
			if(ret < 0 )
			{
				EXILE_LOG_ERROR("Error: Failed to remount %s: %s\n", path_inside_chroot, strerror(errno));
				return ret;
			}
		}
		path_policy = path_policy->next;
	}

	return 0;
}

/*
 * Frees the memory taken by a exile_policy object
 */
void exile_free_policy(struct exile_policy *ctxt)
{
	if(ctxt != NULL)
	{
		struct exile_path_policy *current = ctxt->path_policies;
		while(current != NULL)
		{
			struct exile_path_policy *tmp = current;
			current = current->next;
			free(tmp);
		}

		struct exile_syscall_policy *sc_policy = ctxt->syscall_policies;
		while(sc_policy != NULL)
		{
			struct exile_syscall_policy *tmp = sc_policy;
			sc_policy = sc_policy->next;
			free(tmp);
		}
		free(ctxt);
	}
}

/* Enters the specified namespaces */
static int enter_namespaces(int namespace_options)
{
	if(namespace_options & EXILE_UNSHARE_USER)
	{
		int ret = unshare(CLONE_NEWUSER);
		if(ret == -1)
		{
			EXILE_LOG_ERROR("Error: Failed to unshare user namespaces: %s\n", strerror(errno));
			return ret;
		}

		uid_t current_uid = getuid();
		gid_t current_gid = getgid();

		FILE *fp = fopen("/proc/self/setgroups", "w");
		if(fp == NULL)
		{
			EXILE_LOG_ERROR("fopen failed while trying to deny setgroups\n");
			return -1;
		}
		if(fprintf(fp, "deny") < 0)
		{
			EXILE_LOG_ERROR("fprintf failed while trying to write setgroups\n");
			return -1;
		}
		fclose(fp);

		fp = fopen("/proc/self/uid_map", "w");
		if(fp == NULL)
		{
			EXILE_LOG_ERROR("fopen failed while trying to write uid_map\n");
			return -1;
		}
		if(fprintf(fp, "0 %i", current_uid) < 0)
		{
			EXILE_LOG_ERROR("fprintf failed while trying to write uid_map\n");
			return -1;
		}
		fclose(fp);

		fp = fopen("/proc/self/gid_map", "w");
		if(fp == NULL)
		{
			EXILE_LOG_ERROR("fopen failed while trying to write gid_map\n");
			return -1;
		}
		if(fprintf(fp, "0 %i", current_gid) < 0)
		{
			EXILE_LOG_ERROR("fprintf failed while trying to write gid_map\n");
			return -1;
		}
		fclose(fp);
	}

	if(namespace_options & EXILE_UNSHARE_MOUNT)
	{
		int ret = unshare(CLONE_NEWNS);
		if(ret == -1)
		{
			EXILE_LOG_ERROR("Error: Failed to unshare mount namespaces: %s\n", strerror(errno));
			return ret;
		}
	}

	if(namespace_options & EXILE_UNSHARE_NETWORK)
	{
		int ret = unshare(CLONE_NEWNET);
		if(ret == -1)
		{
			EXILE_LOG_ERROR("Error: Failed to unshare network namespace: %s\n", strerror(errno));
			return ret;
		}
	}

	return 0;
}

/* Drops all capabiltiies held by the process
 *
 * @returns: 0 on sucess, -1 on error
*/
static int drop_caps()
{
	int cap = 0;
	int res = 0;
	while((res = prctl(PR_CAPBSET_DROP, cap, 0, 0, 0)) == 0)
	{
		++cap;
	}

	if(res == -1 && errno != EINVAL)
	{
		EXILE_LOG_ERROR("Failed to drop the capability bounding set!\n");
		return -errno;
	}

	//TODO: systems that are not 64 bit
	struct __user_cap_header_struct h = { 0 };
	h.pid = 0;
	h.version = _LINUX_CAPABILITY_VERSION_3;
	struct __user_cap_data_struct drop[2];
	drop[0].effective = 0;
	drop[0].permitted = 0;
	drop[0].inheritable = 0;
	drop[1].effective = 0;
	drop[1].permitted = 0;
	drop[1].inheritable = 0;
	if(capset(&h, drop) == -1)
	{
		EXILE_LOG_ERROR("Failed to drop capabilities: %s\n", strerror(errno));
		return -errno;
	}
	return 0;
}



static void append_syscall_to_bpf(struct exile_syscall_policy *syscallpolicy, struct sock_filter *filter, unsigned short int *start_index)
{
	unsigned int action = syscallpolicy->policy;
	if(action == EXILE_SYSCALL_ALLOW)
	{
		action = SECCOMP_RET_ALLOW;
	}
	if(action == EXILE_SYSCALL_DENY_KILL_PROCESS)
	{
		action = SECCOMP_RET_KILL_PROCESS;
	}
	if(action == EXILE_SYSCALL_DENY_RET_ERROR)
	{
		action = SECCOMP_RET_ERRNO|EACCES;
	}
	long syscall = syscallpolicy->syscall;

	struct sock_filter syscall_load = BPF_STMT(BPF_LD+BPF_W+BPF_ABS, offsetof(struct seccomp_data, nr));
	filter[(*start_index)++] = 	syscall_load;
	if(syscall != EXILE_SYSCALL_MATCH_ALL)
	{
			/* How many steps forward to jump when we don't match. This is either the last statement,
			 * i. e. the default action or the next syscall policy */
			__u8 next_syscall_pc =  1;
			if(__builtin_add_overflow(next_syscall_pc,  syscallpolicy->argfilterscount, &next_syscall_pc))
			{
					EXILE_LOG_ERROR("Error: Overflow while trying to calculate jump offset\n");
					/* TODO: Return error */
					return;
			}
			struct sock_filter syscall_check = EXILE_BPF_CMP_EQ((unsigned int) syscall, 0, next_syscall_pc);
			filter[(*start_index)++] = syscall_check;
			--next_syscall_pc;

			for(size_t i = 0; i < syscallpolicy->argfilterscount; i++)
			{
				filter[*start_index] = syscallpolicy->argfilters[i];
				__u8 jump_count_next_syscall = next_syscall_pc;
				__u8 jump_count_return = jump_count_next_syscall - 1;
				if(filter[*start_index].jt == EXILE_SYSCALL_EXIT_BPF_NO_MATCH)
				{
					filter[*start_index].jt = jump_count_next_syscall;
				}
				if(filter[*start_index].jt == EXILE_SYSCALL_EXIT_BPF_RETURN)
				{
					filter[*start_index].jt = jump_count_return;
				}
				if(filter[*start_index].jf == EXILE_SYSCALL_EXIT_BPF_NO_MATCH)
				{
					filter[*start_index].jf = jump_count_next_syscall;
				}
				if(filter[*start_index].jf == EXILE_SYSCALL_EXIT_BPF_RETURN)
				{
					filter[*start_index].jf = jump_count_return;
				}
				--next_syscall_pc;
				++*start_index;
			}
	}
	struct sock_filter syscall_action = BPF_STMT(BPF_RET+BPF_K, action);
	/* TODO: we can do better than adding this below every jump */
	filter[(*start_index)++] = syscall_action;

}
/*
 * Enables the seccomp policy
 *
 * policy: exile policy object
 *
 * @returns: 0 on success, -1 on error
 */

static int exile_enable_syscall_policy(struct exile_policy *policy)
{
	struct sock_filter filter[1024] =
	{
		BPF_STMT(BPF_LD+BPF_W+BPF_ABS,offsetof(struct seccomp_data, arch)),
		BPF_JUMP (BPF_JMP+BPF_JEQ+BPF_K, SECCOMP_AUDIT_ARCH, 1, 0),
		BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL_PROCESS),
		BPF_STMT(BPF_LD+BPF_W+BPF_ABS, offsetof(struct seccomp_data, nr)),
		BPF_JUMP(BPF_JMP+BPF_JGE+BPF_K, __X32_SYSCALL_BIT, 0, 1),
		BPF_STMT(BPF_RET+BPF_K, SECCOMP_RET_KILL_PROCESS),
	};

	unsigned short int current_filter_index = 6;

	struct exile_syscall_policy *current_policy = policy->syscall_policies;
	while(current_policy)
	{
		if(!is_valid_syscall_policy(current_policy->policy))
		{
			EXILE_LOG_ERROR("invalid syscall policy specified\n");
			return -1;
		}
		/* TODO: reintroduce overflow checks */
		append_syscall_to_bpf(current_policy, filter, &current_filter_index);
		current_policy = current_policy->next;
	}

	struct sock_fprog prog = {
		.len = current_filter_index ,
		.filter = filter,
	};

	if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog) == -1)
	{
		EXILE_LOG_ERROR("prctl SET_SECCOMP %s\n", strerror(errno));
		return -1;
	}

	return 0;
}

#if HAVE_LANDLOCK == 1
static unsigned int exile_flags_to_landlock(unsigned int flags)
{
	unsigned int result = 0;
	if(flags & EXILE_FS_ALLOW_ALL_READ)
	{
		result |= LANDLOCK_ACCESS_FS_READ_FILE;
		result |= LANDLOCK_ACCESS_FS_READ_DIR;
	}
	if(flags & EXILE_FS_ALLOW_ALL_WRITE)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_REG;
		result |= LANDLOCK_ACCESS_FS_WRITE_FILE;
		result |= LANDLOCK_ACCESS_FS_REMOVE_DIR;
		result |= LANDLOCK_ACCESS_FS_REMOVE_FILE;
		result |= LANDLOCK_ACCESS_FS_MAKE_SYM;
	}
	if(flags & EXILE_FS_ALLOW_DEV)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_BLOCK;
		result |= LANDLOCK_ACCESS_FS_MAKE_CHAR;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_BLOCK)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_BLOCK;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_CHAR)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_CHAR;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_DIR)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_DIR;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_FIFO)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_FIFO;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_REG)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_REG;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_SOCK)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_SOCK;
	}
	if(flags & EXILE_FS_ALLOW_MAKE_SYM)
	{
		result |= LANDLOCK_ACCESS_FS_MAKE_SYM;
	}
	if(flags & EXILE_FS_ALLOW_REMOVE)
	{
		result |= LANDLOCK_ACCESS_FS_REMOVE_DIR;
		result |= LANDLOCK_ACCESS_FS_REMOVE_FILE;
	}
	if(flags & EXILE_FS_ALLOW_REMOVE_DIR)
	{
		result |= LANDLOCK_ACCESS_FS_REMOVE_DIR;
	}
	if(flags & EXILE_FS_ALLOW_REMOVE_FILE)
	{
		result |= LANDLOCK_ACCESS_FS_REMOVE_FILE;
	}
	if(flags & EXILE_FS_ALLOW_EXEC)
	{
		result |= LANDLOCK_ACCESS_FS_EXECUTE;
	}
	if(flags & EXILE_FS_ALLOW_WRITE_FILE)
	{
		result |= LANDLOCK_ACCESS_FS_WRITE_FILE;
	}
	if(flags & EXILE_FS_ALLOW_READ_DIR)
	{
		result |= LANDLOCK_ACCESS_FS_READ_DIR;
	}
	return result;
}

static int landlock_prepare_ruleset(struct exile_path_policy *policies)
{
	int ruleset_fd = -1;
	struct landlock_ruleset_attr ruleset_attr;
	/* We here want the maximum possible ruleset, so set the var to the max possible bitmask.
	   Stolen/Adapted from: [linux src]/security/landlock/limits.h
	*/
	ruleset_attr.handled_access_fs = ((LANDLOCK_ACCESS_FS_MAKE_SYM << 1) - 1);

	ruleset_fd = landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
	if (ruleset_fd < 0)
	{
		EXILE_LOG_ERROR("Failed to create landlock ruleset\n");
		return -1;
	}
	struct exile_path_policy *policy = policies;
	while(policy != NULL)
	{
		struct landlock_path_beneath_attr path_beneath;
		path_beneath.parent_fd = open(policy->path, O_PATH | O_CLOEXEC);
		if(path_beneath.parent_fd < 0)
		{
			EXILE_LOG_ERROR("Failed to open policy path %s while preparing landlock ruleset\n", policy->path);
			close(ruleset_fd);
			return path_beneath.parent_fd;
		}
		path_beneath.allowed_access = exile_flags_to_landlock(policy->policy);
		int ret = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH, &path_beneath, 0);
		if(ret)
		{
			EXILE_LOG_ERROR("Failed to update ruleset while processsing policy path %s\n", policy->path);
			close(ruleset_fd);
			return ret;
		}
		policy = policy->next;
	}
	return ruleset_fd;
}
#endif


/* Checks for illogical or dangerous combinations */
static int check_policy_sanity(struct exile_policy *policy)
{
	if(policy->no_new_privs != 1)
	{
		if(policy->syscall_policies != NULL)
		{
			EXILE_LOG_ERROR("no_new_privs = 1 is required for seccomp filtering!\n");
			return -1;
		}
	}

	/* TODO: check if we have ALLOWED, but no default deny */

	if(policy->mount_path_policies_to_chroot == 1)
	{
		if(policy->path_policies == NULL)
		{
			EXILE_LOG_ERROR("Cannot mount path policies to chroot if non are given\n");
			return -1;
		}
		if(!(policy->namespace_options & EXILE_UNSHARE_MOUNT))
		{
			EXILE_LOG_ERROR("mount_path_policies_to_chroot = 1 requires unsharing mount namespace\n");
			return -1;
		}
	}


	if(policy->path_policies != NULL)
	{

		if(policy->mount_path_policies_to_chroot != 1)
		{
			#if HAVE_LANDLOCK != 1
				EXILE_LOG_ERROR("Path policies cannot be enforced! System needs landlock support or set mount_path_policies_to_chroot = 1\n");
				return -1;
			#endif
		}
		if(policy->no_fs == 1)
		{
			EXILE_LOG_ERROR("If path_policies are specified, no_fs cannot be set to 1\n");
			return -1;
		}
	}

	struct exile_syscall_policy *syscall_policy = policy->syscall_policies;
	if(syscall_policy != NULL)
	{
		/* A few sanitiy checks... but we cannot check overall whether it's reasonable */
		int i = 0;
		int last_match_all = -1;
		int match_all_policy = 0;
		int last_policy = 0;
		while(syscall_policy)
		{
			if(syscall_policy->syscall == EXILE_SYSCALL_MATCH_ALL)
			{
				last_match_all = i;
				match_all_policy = syscall_policy->policy;
			}
			else
			{
				last_policy = syscall_policy->policy;
			}
			syscall_policy = syscall_policy->next;
			++i;
		}
		if(last_match_all == -1 || i - last_match_all != 1)
		{
			EXILE_LOG_ERROR("The last entry in the syscall policy list must match all syscalls (default rule)\n");
			return -1;
		}
		/* Most likely a mistake and not intended */
		if(last_policy == match_all_policy)
		{
			EXILE_LOG_ERROR("Last policy for a syscall matches default policy\n");
			return -1;
		}
	}

	return 0;
}

static void close_file_fds()
{
	long max_files = sysconf(_SC_OPEN_MAX);
	for(long i = 3; i <= max_files; i++)
	{
		close((int)i);
	}
}

/* Takes away file system access from the process
 *
 * We use this when "no_fs" is given in the policy.
 *
 * This is useful for restricted subprocesses that do some computational work
 * and do not require filesystem access
 *
 * @returns: 0 on success, < 0 on error
 */
static int enable_no_fs(struct exile_policy *policy)
{
		close_file_fds();

		if(chdir("/proc/self/fdinfo") != 0)
		{
			EXILE_LOG_ERROR("Failed to change to safe directory: %s\n", strerror(errno));
			return -1;
		}

		if(chroot(".") != 0)
		{
			EXILE_LOG_ERROR("Failed to chroot into safe directory: %s\n", strerror(errno));
			return -1;
		}

		if(chdir("/") != 0)
		{
			EXILE_LOG_ERROR("Failed to chdir into safe directory inside chroot: %s\n", strerror(errno));
			return -1;
		}

		return 0;
}

/* Enables the specified exile_policy.
 *
 * This function is not atomic (and can't be). This means some
 * policies can apply, while others may fail.
 *
 * This function returns success only if all policies applied.
 *
 * The state is undefined if this function fails. The process generally
 * should exit.
 *
 * @returns: 0 on success (all policies applied), < 0 on error (none or some policies dit not apply)
 */
int exile_enable_policy(struct exile_policy *policy)
{
	if(check_policy_sanity(policy) != 0)
	{
		EXILE_LOG_ERROR("Error: Policy sanity check failed. Cannot apply policy!\n");
		return -EINVAL;
	}

	if(enter_namespaces(policy->namespace_options) < 0)
	{
		EXILE_LOG_ERROR("Error while trying to enter namespaces\n");
		return -1;
	}

	if(policy->mount_path_policies_to_chroot && policy->path_policies != NULL)
	{
		if(*policy->chroot_target_path == '\0')
		{
			char random_str[17];
			if(random_string(random_str, sizeof(random_str)) == 16)
			{
				int res = snprintf(policy->chroot_target_path, sizeof(policy->chroot_target_path), "%s/.sandbox_%" PRIdMAX "_%s", EXILE_TEMP_DIR, (intmax_t)getpid(), random_str);
				if(res < 0)
				{
					EXILE_LOG_ERROR("exile: exile_enable_policy: error during path concatination\n");
					return -EINVAL;
				}
				if(res >= PATH_MAX)
				{
					EXILE_LOG_ERROR("exile: exile_enable_policy: path concatination truncated\n");
					return -EINVAL;
				}
			}
			else
			{
				EXILE_LOG_ERROR("Error creating random sandbox directory name\n");
				return -1;
			}
		}

		if(mount_to_chroot(policy->chroot_target_path, policy->path_policies) < 0)
		{
			EXILE_LOG_ERROR("mount_to_chroot: bind mounting of path policies failed\n");
			return -1;
		}
	}

	if(*policy->chroot_target_path != '\0')
	{
		if(chroot(policy->chroot_target_path) < 0)
		{
			EXILE_LOG_ERROR("chroot: failed to enter %s\n", policy->chroot_target_path);
			return -1;
		}
		const char *chdir_target_path = policy->chdir_path;
		if(chdir_target_path == NULL)
		{
			chdir_target_path = "/";
		}

		if(chdir(chdir_target_path) < 0)
		{
			EXILE_LOG_ERROR("chdir to %s failed\n", policy->chdir_path);
			return -1;
		}
	}

#if HAVE_LANDLOCK == 1
	int landlock_ruleset_fd = -1;
	if(policy->path_policies != NULL)
	{
		landlock_ruleset_fd = landlock_prepare_ruleset(policy->path_policies);
		if(landlock_ruleset_fd < 0)
		{
			EXILE_LOG_ERROR("landlock_prepare_ruleset: Failed to prepare landlock ruleset: %s\n", strerror(errno));
			return -1;
		}
	}
#endif

	if(policy->no_fs)
	{
		if(enable_no_fs(policy) != 0)
		{
			EXILE_LOG_ERROR("Failed to take away filesystem access of process\n");
			return -1;
		}
	}

	if(policy->no_new_fds)
	{
		const struct rlimit nofile = {0, 0};
		if (setrlimit(RLIMIT_NOFILE, &nofile) == -1)
		{
			EXILE_LOG_ERROR("setrlimit: Failed to set rlimit: %s\n", strerror(errno));
			return -1;
		}
	}

	if(policy->drop_caps)
	{
		if(drop_caps() < 0)
		{
			EXILE_LOG_ERROR("failed to drop capabilities\n");
			return -1;
		}
	}

	if(policy->not_dumpable)
	{
		if(prctl(PR_SET_DUMPABLE, 0) == -1)
		{
			EXILE_LOG_ERROR("prctl: PR_SET_DUMPABLE failed\n");
			return -1;
		}
	}

	if(policy->no_new_privs)
	{
		if(prctl(PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0) == -1)
		{
			EXILE_LOG_ERROR("prctl: PR_SET_NO_NEW_PRIVS failed: %s\n", strerror(errno));
			return -1;
		}
	}

#if HAVE_LANDLOCK == 1
	if (policy->path_policies != NULL && landlock_restrict_self(landlock_ruleset_fd, 0) != 0)
	{
		perror("Failed to enforce ruleset");
		close(landlock_ruleset_fd);
		return -1;
	}
	close(landlock_ruleset_fd);
#endif

	if(policy->pledge_promises != 0)
	{
		int ret = exile_append_pledge_promises(policy, policy->pledge_promises);
		if(ret != 0)
		{
			EXILE_LOG_ERROR("exile_append_pledge_promises() failed: %i\n", ret);
			return ret;
		}
	}

	if(policy->syscall_policies != NULL)
	{
		return exile_enable_syscall_policy(policy);
	}


	return 0;
}
#endif


/* Convenience wrapper for the pledge-related subset of exile.h
 *
 * Only installs seccomp filters for the specified pledge promises.
 *
 * Useful if only pledge is required from exile.h, but nothing else
 *
 * As with OpenBSD's, subsequent calls can only reduce allowed syscalls.
 *
 * Here, adding more promises than a previous call set may return success, but
 * won't be allowed during execution.
 *
 * Due to the nature of seccomp, it's furthermore required the EXILE_SYSCALL_PLEDGE_SECCOMP_INSTALL promise
 * is set if further calls are expected. Generally, it's reasonable for the last call to
 * exile_pledge() a program makes to not set EXILE_SYSCALL_PLEDGE_SECCOMP_INSTALL.
 *
 * There are no seperate exec_promises. All children of the process inherit the filter.
 * .
 * Return value: 0 on success, any other value on failure.
 */
int exile_pledge(uint64_t promises)
{
	struct __user_cap_header_struct h = { 0 };
	h.pid = 0;
	h.version = _LINUX_CAPABILITY_VERSION_3;
	struct __user_cap_data_struct cap[2];
	cap[0].effective = 0;
	cap[0].permitted = 0;
	cap[0].inheritable = 0;
	cap[1].effective = 0;
	cap[1].permitted = 0;
	cap[1].inheritable = 0;
	if(capget(&h, cap) == -1)
	{
		EXILE_LOG_ERROR("Failed to get capabilities: %s\n", strerror(errno));
		return -errno;
	}

	struct exile_policy *policy = exile_create_policy();
	if(policy == NULL)
	{
		EXILE_LOG_ERROR("Failed to create policy\n");
		return 1;
	}

	policy->pledge_promises = promises;
	if((cap[0].effective & (1<<CAP_SYS_ADMIN)) == 0)
	{
		policy->no_new_privs = 1;
	}
	int ret = exile_enable_policy(policy);
	exile_free_policy(policy);
	return ret;
}