/*-
 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
 *
 * Copyright (c) 1999-2001 Robert N. M. Watson
 * Copyright (c) 2008 Edward Tomasz Napierała <trasz@FreeBSD.org>
 * All rights reserved.
 *
 * This software was developed by Robert Watson for the TrustedBSD Project.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * $FreeBSD: head/sys/sys/acl.h 326256 2017-11-27 15:01:59Z pfg $
 */
/* 
 * Developed by the TrustedBSD Project.
 * Support for POSIX.1e and NFSv4 access control lists.
 */

#ifndef _SYS_ACL_H_
#define _SYS_ACL_H_

#include <sys/param.h>
#include <sys/queue.h>

/*
 * POSIX.1e and NFSv4 ACL types and related constants.
 */

typedef uint32_t        acl_tag_t;
typedef uint32_t        acl_perm_t;
typedef uint16_t        acl_entry_type_t;
typedef uint16_t        acl_flag_t;
typedef int             acl_type_t;
typedef uint32_t        *acl_permset_t;
typedef uint16_t        *acl_flagset_t;

/*
 * With 254 entries, "struct acl_t_struct" is exactly one 4kB page big.
 * Note that with NFSv4 ACLs, the maximum number of ACL entries one
 * may set on file or directory is about half of ACL_MAX_ENTRIES.
 *
 * If you increase this, you might also need to increase
 * _ACL_T_ALIGNMENT_BITS in lib/libc/posix1e/acl_support.h.
 *
 * The maximum number of POSIX.1e ACLs is controlled
 * by OLDACL_MAX_ENTRIES.  Changing that one will break binary
 * compatibility with pre-8.0 userland and change on-disk ACL layout.
 */
#define ACL_MAX_ENTRIES                         254

#if defined(_KERNEL) || defined(_ACL_PRIVATE) || defined(_MODULE)

#define POSIX1E_ACL_ACCESS_EXTATTR_NAMESPACE    EXTATTR_NAMESPACE_SYSTEM
#define POSIX1E_ACL_ACCESS_EXTATTR_NAME         "posix1e.acl_access"
#define POSIX1E_ACL_DEFAULT_EXTATTR_NAMESPACE   EXTATTR_NAMESPACE_SYSTEM
#define POSIX1E_ACL_DEFAULT_EXTATTR_NAME        "posix1e.acl_default"
#define NFS4_ACL_EXTATTR_NAMESPACE              EXTATTR_NAMESPACE_SYSTEM
#define NFS4_ACL_EXTATTR_NAME                   "nfs4.acl"
#define OLDACL_MAX_ENTRIES                      32

/*
 * "struct oldacl" is used in compatibility ACL syscalls and for on-disk
 * storage of POSIX.1e ACLs.
 */
typedef int     oldacl_tag_t;
typedef mode_t  oldacl_perm_t;

struct oldacl_entry {
        oldacl_tag_t    ae_tag;
        uid_t           ae_id;
        oldacl_perm_t   ae_perm;
};
typedef struct oldacl_entry     *oldacl_entry_t;

struct oldacl {
        int                     acl_cnt;
        struct oldacl_entry     acl_entry[OLDACL_MAX_ENTRIES];
};

/*
 * Current "struct acl".
 */
struct acl_entry {
        acl_tag_t               ae_tag;
        uid_t                   ae_id;
        acl_perm_t              ae_perm;
        /* NFSv4 entry type, "allow" or "deny".  Unused in POSIX.1e ACLs. */
        acl_entry_type_t        ae_entry_type;
        /* NFSv4 ACL inheritance.  Unused in POSIX.1e ACLs. */
        acl_flag_t              ae_flags;
};
typedef struct acl_entry        *acl_entry_t;

/*
 * Internal ACL structure, used in libc, kernel APIs and for on-disk
 * storage of NFSv4 ACLs.  POSIX.1e ACLs use "struct oldacl" for on-disk
 * storage.
 */
struct acl {
        unsigned int            acl_maxcnt;
        unsigned int            acl_cnt;
        /* Will be required e.g. to implement NFSv4.1 ACL inheritance. */
        int                     acl_spare[4];
        struct acl_entry        acl_entry[ACL_MAX_ENTRIES];
};

/*
 * ACL structure internal to libc.
 */
struct acl_t_struct {
        struct acl              ats_acl;
        unsigned int            ats_cur_entry;
        /*
         * ats_brand is for libc internal bookkeeping only.
         * Applications should use acl_get_brand_np(3).
         * Kernel code should use the "type" argument passed
         * to VOP_SETACL, VOP_GETACL or VOP_ACLCHECK calls;
         * ACL_TYPE_ACCESS or ACL_TYPE_DEFAULT mean POSIX.1e
         * ACL, ACL_TYPE_NFS4 means NFSv4 ACL.
         */
        int                     ats_brand;
};
typedef struct acl_t_struct *acl_t;

#else /* _KERNEL || _ACL_PRIVATE */

typedef void *acl_entry_t;
typedef void *acl_t;

#endif /* !_KERNEL && !_ACL_PRIVATE */

/*
 * Possible valid values for ats_brand field.
 */
#define ACL_BRAND_UNKNOWN       0
#define ACL_BRAND_POSIX         1
#define ACL_BRAND_NFS4          2

/*
 * Possible valid values for ae_tag field.  For explanation, see acl(9).
 */
#define ACL_UNDEFINED_TAG       0x00000000
#define ACL_USER_OBJ            0x00000001
#define ACL_USER                0x00000002
#define ACL_GROUP_OBJ           0x00000004
#define ACL_GROUP               0x00000008
#define ACL_MASK                0x00000010
#define ACL_OTHER               0x00000020
#define ACL_OTHER_OBJ           ACL_OTHER
#define ACL_EVERYONE            0x00000040

/*
 * Possible valid values for ae_entry_type field, valid only for NFSv4 ACLs.
 */
#define ACL_ENTRY_TYPE_ALLOW    0x0100
#define ACL_ENTRY_TYPE_DENY     0x0200
#define ACL_ENTRY_TYPE_AUDIT    0x0400
#define ACL_ENTRY_TYPE_ALARM    0x0800

/*
 * Possible valid values for acl_type_t arguments.  First two
 * are provided only for backwards binary compatibility.
 */
#define ACL_TYPE_ACCESS_OLD     0x00000000
#define ACL_TYPE_DEFAULT_OLD    0x00000001
#define ACL_TYPE_ACCESS         0x00000002
#define ACL_TYPE_DEFAULT        0x00000003
#define ACL_TYPE_NFS4           0x00000004

/*
 * Possible bits in ae_perm field for POSIX.1e ACLs.  Note
 * that ACL_EXECUTE may be used in both NFSv4 and POSIX.1e ACLs.
 */
#define ACL_EXECUTE             0x0001
#define ACL_WRITE               0x0002
#define ACL_READ                0x0004
#define ACL_PERM_NONE           0x0000
#define ACL_PERM_BITS           (ACL_EXECUTE | ACL_WRITE | ACL_READ)
#define ACL_POSIX1E_BITS        (ACL_EXECUTE | ACL_WRITE | ACL_READ)

/*
 * Possible bits in ae_perm field for NFSv4 ACLs.
 */
#define ACL_READ_DATA           0x00000008
#define ACL_LIST_DIRECTORY      0x00000008
#define ACL_WRITE_DATA          0x00000010
#define ACL_ADD_FILE            0x00000010
#define ACL_APPEND_DATA         0x00000020
#define ACL_ADD_SUBDIRECTORY    0x00000020
#define ACL_READ_NAMED_ATTRS    0x00000040
#define ACL_WRITE_NAMED_ATTRS   0x00000080
/* ACL_EXECUTE is defined above. */
#define ACL_DELETE_CHILD        0x00000100
#define ACL_READ_ATTRIBUTES     0x00000200
#define ACL_WRITE_ATTRIBUTES    0x00000400
#define ACL_DELETE              0x00000800
#define ACL_READ_ACL            0x00001000
#define ACL_WRITE_ACL           0x00002000
#define ACL_WRITE_OWNER         0x00004000
#define ACL_SYNCHRONIZE         0x00008000

#define ACL_FULL_SET            (ACL_READ_DATA | ACL_WRITE_DATA | \
    ACL_APPEND_DATA | ACL_READ_NAMED_ATTRS | ACL_WRITE_NAMED_ATTRS | \
    ACL_EXECUTE | ACL_DELETE_CHILD | ACL_READ_ATTRIBUTES | \
    ACL_WRITE_ATTRIBUTES | ACL_DELETE | ACL_READ_ACL | ACL_WRITE_ACL | \
    ACL_WRITE_OWNER | ACL_SYNCHRONIZE)

#define ACL_MODIFY_SET          (ACL_FULL_SET & \
    ~(ACL_WRITE_ACL | ACL_WRITE_OWNER))

#define ACL_READ_SET            (ACL_READ_DATA | ACL_READ_NAMED_ATTRS | \
    ACL_READ_ATTRIBUTES | ACL_READ_ACL)

#define ACL_WRITE_SET           (ACL_WRITE_DATA | ACL_APPEND_DATA | \
    ACL_WRITE_NAMED_ATTRS | ACL_WRITE_ATTRIBUTES)

#define ACL_NFS4_PERM_BITS      ACL_FULL_SET

/*
 * Possible entry_id values for acl_get_entry(3).
 */
#define ACL_FIRST_ENTRY         0
#define ACL_NEXT_ENTRY          1

/*
 * Possible values in ae_flags field; valid only for NFSv4 ACLs.
 */
#define ACL_ENTRY_FILE_INHERIT          0x0001
#define ACL_ENTRY_DIRECTORY_INHERIT     0x0002
#define ACL_ENTRY_NO_PROPAGATE_INHERIT  0x0004
#define ACL_ENTRY_INHERIT_ONLY          0x0008
#define ACL_ENTRY_SUCCESSFUL_ACCESS     0x0010
#define ACL_ENTRY_FAILED_ACCESS         0x0020
#define ACL_ENTRY_INHERITED             0x0080

#define ACL_FLAGS_BITS                  (ACL_ENTRY_FILE_INHERIT | \
    ACL_ENTRY_DIRECTORY_INHERIT | ACL_ENTRY_NO_PROPAGATE_INHERIT | \
    ACL_ENTRY_INHERIT_ONLY | ACL_ENTRY_SUCCESSFUL_ACCESS | \
    ACL_ENTRY_FAILED_ACCESS | ACL_ENTRY_INHERITED)

/*
 * Undefined value in ae_id field.  ae_id should be set to this value
 * iff ae_tag is ACL_USER_OBJ, ACL_GROUP_OBJ, ACL_OTHER or ACL_EVERYONE.
 */
#define ACL_UNDEFINED_ID        ((uid_t)-1)

/*
 * Possible values for _flags parameter in acl_to_text_np(3).
 */
#define ACL_TEXT_VERBOSE        0x01
#define ACL_TEXT_NUMERIC_IDS    0x02
#define ACL_TEXT_APPEND_ID      0x04

/*
 * POSIX.1e ACLs are capable of expressing the read, write, and execute bits
 * of the POSIX mode field.  We provide two masks: one that defines the bits
 * the ACL will replace in the mode, and the other that defines the bits that
 * must be preseved when an ACL is updating a mode.
 */
#define ACL_OVERRIDE_MASK       (S_IRWXU | S_IRWXG | S_IRWXO)
#define ACL_PRESERVE_MASK       (~ACL_OVERRIDE_MASK)

#ifdef _KERNEL

/*
 * Filesystem-independent code to move back and forth between POSIX mode and
 * POSIX.1e ACL representations.
 */
acl_perm_t              acl_posix1e_mode_to_perm(acl_tag_t tag, mode_t mode);
struct acl_entry        acl_posix1e_mode_to_entry(acl_tag_t tag, uid_t uid,
                            gid_t gid, mode_t mode);
mode_t                  acl_posix1e_perms_to_mode(
                            struct acl_entry *acl_user_obj_entry,
                            struct acl_entry *acl_group_obj_entry,
                            struct acl_entry *acl_other_entry);
mode_t                  acl_posix1e_acl_to_mode(struct acl *acl);
mode_t                  acl_posix1e_newfilemode(mode_t cmode,
                            struct acl *dacl);
struct acl              *acl_alloc(int flags);
void                    acl_free(struct acl *aclp);

void                    acl_nfs4_sync_acl_from_mode(struct acl *aclp,
                            mode_t mode, int file_owner_id);
void                    __acl_nfs4_sync_mode_from_acl(mode_t *mode,
                            const struct acl *aclp);
int                     acl_nfs4_is_trivial(const struct acl *aclp,
                            int file_owner_id);
void                    acl_nfs4_compute_inherited_acl(
                            const struct acl *parent_aclp,
                            struct acl *child_aclp, mode_t mode,
                            int file_owner_id, int is_directory);
int                     acl_copy_oldacl_into_acl(const struct oldacl *source,
                            struct acl *dest);
int                     acl_copy_acl_into_oldacl(const struct acl *source,
                            struct oldacl *dest);

/*
 * Filesystem-independent syntax check for a POSIX.1e ACL.
 */
int                     acl_posix1e_check(struct acl *acl);
int                     acl_nfs4_check(const struct acl *aclp, int is_directory);

/* for compat32 */
#include <sys/namei.h>

int     kern___acl_aclcheck_path(struct lwp *, const char *, acl_type_t,
    struct acl *, namei_simple_flags_t);
int     kern___acl_delete_path(struct lwp *, const char *, acl_type_t,
    namei_simple_flags_t);
int     kern___acl_get_path(struct lwp *, const char *, acl_type_t,
    struct acl *, namei_simple_flags_t);
int     kern___acl_set_path(struct lwp *, const char *, acl_type_t,
    const struct acl *, namei_simple_flags_t);
int     vacl_set_acl(struct lwp *, struct vnode *, acl_type_t,
    const struct acl *);
int     vacl_get_acl(struct lwp *, struct vnode *, acl_type_t, struct acl *);
int     vacl_aclcheck(struct lwp *, struct vnode *, acl_type_t,
    const struct acl *);
int     vacl_delete(struct lwp *, struct vnode *, acl_type_t);

#else /* !_KERNEL */

#if defined(_ACL_PRIVATE)

/*
 * Syscall interface -- use the library calls instead as the syscalls have
 * strict ACL entry ordering requirements.
 */
__BEGIN_DECLS
int     __acl_aclcheck_fd(int _filedes, acl_type_t _type, struct acl *_aclp);
int     __acl_aclcheck_file(const char *_path, acl_type_t _type,
            struct acl *_aclp);
int     __acl_aclcheck_link(const char *_path, acl_type_t _type,
            struct acl *_aclp);
int     __acl_delete_fd(int _filedes, acl_type_t _type);
int     __acl_delete_file(const char *_path_p, acl_type_t _type);
int     __acl_delete_link(const char *_path_p, acl_type_t _type);
int     __acl_get_fd(int _filedes, acl_type_t _type, struct acl *_aclp);
int     __acl_get_file(const char *_path, acl_type_t _type, struct acl *_aclp);
int     __acl_get_link(const char *_path, acl_type_t _type, struct acl *_aclp);
int     __acl_set_fd(int _filedes, acl_type_t _type, struct acl *_aclp);
int     __acl_set_file(const char *_path, acl_type_t _type, struct acl *_aclp);
int     __acl_set_link(const char *_path, acl_type_t _type, struct acl *_aclp);

/*
 * These routines from sys/kern/subr_acl_nfs4.c are used by both kernel
 * and libc.
 */
void    __acl_nfs4_sync_mode_from_acl(mode_t *_mode, const struct acl *_aclp);
void    __acl_nfs4_trivial_from_mode_libc(struct acl *_aclp, int _file_owner_id,
            int _canonical_six);
__END_DECLS

#endif /* _ACL_PRIVATE */

/*
 * Supported POSIX.1e ACL manipulation and assignment/retrieval API _np calls
 * are local extensions that reflect an environment capable of opening file
 * descriptors of directories, and allowing additional ACL type for different
 * filesystems (i.e., AFS).
 */
__BEGIN_DECLS
int     acl_add_flag_np(acl_flagset_t _flagset_d, acl_flag_t _flag);
int     acl_add_perm(acl_permset_t _permset_d, acl_perm_t _perm);
int     acl_calc_mask(acl_t *_acl_p);
int     acl_clear_flags_np(acl_flagset_t _flagset_d);
int     acl_clear_perms(acl_permset_t _permset_d);
int     acl_copy_entry(acl_entry_t _dest_d, acl_entry_t _src_d);
ssize_t acl_copy_ext(void *_buf_p, acl_t _acl, ssize_t _size);
acl_t   acl_copy_int(const void *_buf_p);
int     acl_create_entry(acl_t *_acl_p, acl_entry_t *_entry_p);
int     acl_create_entry_np(acl_t *_acl_p, acl_entry_t *_entry_p, int _index);
int     acl_delete_entry(acl_t _acl, acl_entry_t _entry_d);
int     acl_delete_entry_np(acl_t _acl, int _index);
int     acl_delete_fd_np(int _filedes, acl_type_t _type);
int     acl_delete_file_np(const char *_path_p, acl_type_t _type);
int     acl_delete_link_np(const char *_path_p, acl_type_t _type);
int     acl_delete_def_file(const char *_path_p);
int     acl_delete_def_link_np(const char *_path_p);
int     acl_delete_flag_np(acl_flagset_t _flagset_d, acl_flag_t _flag);
int     acl_delete_perm(acl_permset_t _permset_d, acl_perm_t _perm);
acl_t   acl_dup(acl_t _acl);
int     acl_free(void *_obj_p);
acl_t   acl_from_text(const char *_buf_p);
int     acl_get_brand_np(acl_t _acl, int *_brand_p);
int     acl_get_entry(acl_t _acl, int _entry_id, acl_entry_t *_entry_p);
acl_t   acl_get_fd(int _fd);
acl_t   acl_get_fd_np(int fd, acl_type_t _type);
acl_t   acl_get_file(const char *_path_p, acl_type_t _type);
int     acl_get_entry_type_np(acl_entry_t _entry_d, acl_entry_type_t *_entry_type_p);
acl_t   acl_get_link_np(const char *_path_p, acl_type_t _type);
void    *acl_get_qualifier(acl_entry_t _entry_d);
int     acl_get_flag_np(acl_flagset_t _flagset_d, acl_flag_t _flag);
int     acl_get_perm_np(acl_permset_t _permset_d, acl_perm_t _perm);
int     acl_get_flagset_np(acl_entry_t _entry_d, acl_flagset_t *_flagset_p);
int     acl_get_permset(acl_entry_t _entry_d, acl_permset_t *_permset_p);
int     acl_get_tag_type(acl_entry_t _entry_d, acl_tag_t *_tag_type_p);
acl_t   acl_init(int _count);
int     acl_set_fd(int _fd, acl_t _acl);
int     acl_set_fd_np(int _fd, acl_t _acl, acl_type_t _type);
int     acl_set_file(const char *_path_p, acl_type_t _type, acl_t _acl);
int     acl_set_entry_type_np(acl_entry_t _entry_d, acl_entry_type_t _entry_type);
int     acl_set_link_np(const char *_path_p, acl_type_t _type, acl_t _acl);
int     acl_set_flagset_np(acl_entry_t _entry_d, acl_flagset_t _flagset_d);
int     acl_set_permset(acl_entry_t _entry_d, acl_permset_t _permset_d);
int     acl_set_qualifier(acl_entry_t _entry_d, const void *_tag_qualifier_p);
int     acl_set_tag_type(acl_entry_t _entry_d, acl_tag_t _tag_type);
ssize_t acl_size(acl_t _acl);
char    *acl_to_text(acl_t _acl, ssize_t *_len_p);
char    *acl_to_text_np(acl_t _acl, ssize_t *_len_p, int _flags);
int     acl_valid(acl_t _acl);
int     acl_valid_fd_np(int _fd, acl_type_t _type, acl_t _acl);
int     acl_valid_file_np(const char *_path_p, acl_type_t _type, acl_t _acl);
int     acl_valid_link_np(const char *_path_p, acl_type_t _type, acl_t _acl);
int     acl_is_trivial_np(const acl_t _acl, int *_trivialp);
acl_t   acl_strip_np(const acl_t _acl, int recalculate_mask);
__END_DECLS

#endif /* !_KERNEL */

#endif /* !_SYS_ACL_H_ */