Ubuntu Manpage: archive_entry_acl_add_entry, archive_entry_acl_add_entry_w, archive_entry_acl

Provided by: libarchive-dev_3.6.0-1ubuntu1_amd64

NAME

     archive_entry_acl_add_entry, archive_entry_acl_add_entry_w, archive_entry_acl_clear,
     archive_entry_acl_count, archive_entry_acl_from_text, archive_entry_acl_from_text_w,
     archive_entry_acl_next, archive_entry_acl_reset, archive_entry_acl_to_text,
     archive_entry_acl_to_text_w, archive_entry_acl_types — functions for manipulating Access
     Control Lists in archive entry descriptions

LIBRARY

     Streaming Archive Library (libarchive, -larchive)

SYNOPSIS

     #include <archive_entry.h>

     void
     archive_entry_acl_add_entry(struct archive_entry *a, int type, int permset, int tag,
         int qualifier, const char *name);

     void
     archive_entry_acl_add_entry_w(struct archive_entry *a, int type, int permset, int tag,
         int qualifier, const wchar_t *name);

     void
     archive_entry_acl_clear(struct archive_entry *a);

     int
     archive_entry_acl_count(struct archive_entry *a, int type);

     int
     archive_entry_acl_from_text(struct archive_entry *a, const char *text, int type);

     int
     archive_entry_acl_from_text_w(struct archive_entry *a, const wchar_t *text, int type);

     int
     archive_entry_acl_next(struct archive_entry *a, int type, int *ret_type, int *ret_permset,
         int *ret_tag, int *ret_qual, const char **ret_name);

     int
     archive_entry_acl_reset(struct archive_entry *a, int type);

     char *
     archive_entry_acl_to_text(struct archive_entry *a, ssize_t *len_p, int flags);

     wchar_t *
     archive_entry_acl_to_text_w(struct archive_entry *a, ssize_t *len_p, int flags);

     int
     archive_entry_acl_types(struct archive_entry *a);

DESCRIPTION

The “Access Control Lists (ACLs)” extend the standard Unix permission model. The ACL
interface of libarchive supports both POSIX.1e and NFSv4 style ACLs. Use of ACLs is
restricted by various levels of ACL support in operating systems, file systems and archive
formats.

POSIX.1e Access Control Lists
A POSIX.1e ACL consists of a number of independent entries. Each entry specifies the
permission set as a bitmask of basic permissions. Valid permissions in the permset are:
ARCHIVE_ENTRY_ACL_READ (r)
ARCHIVE_ENTRY_ACL_WRITE (w)
ARCHIVE_ENTRY_ACL_EXECUTE (x)
The permissions correspond to the normal Unix permissions.

The tag specifies the principal to which the permission applies. Valid values are:
ARCHIVE_ENTRY_ACL_USER The user specified by the name field.
ARCHIVE_ENTRY_ACL_USER_OBJ The owner of the file.
ARCHIVE_ENTRY_ACL_GROUP The group specified by the name field.
ARCHIVE_ENTRY_ACL_GROUP_OBJ The group which owns the file.
ARCHIVE_ENTRY_ACL_MASK The maximum permissions to be obtained via group
permissions.
ARCHIVE_ENTRY_ACL_OTHER Any principal who is not the file owner or a member of
the owning group.

The principals ARCHIVE_ENTRY_ACL_USER_OBJ, ARCHIVE_ENTRY_ACL_GROUP_OBJ and
ARCHIVE_ENTRY_ACL_OTHER are equivalent to user, group and other in the classic Unix
permission model and specify non-extended ACL entries.

All files have an access ACL (ARCHIVE_ENTRY_ACL_TYPE_ACCESS). This specifies the
permissions required for access to the file itself. Directories have an additional ACL
(ARCHIVE_ENTRY_ACL_TYPE_DEFAULT), which controls the initial access ACL for newly-created
directory entries.

NFSv4 Access Control Lists
A NFSv4 ACL consists of multiple individual entries called Access Control Entries (ACEs).

There are four possible types of a NFSv4 ACE:
ARCHIVE_ENTRY_ACL_TYPE_ALLOW Allow principal to perform actions requiring given
permissions.
ARCHIVE_ENTRY_ACL_TYPE_DENY Prevent principal from performing actions requiring given
permissions.
ARCHIVE_ENTRY_ACL_TYPE_AUDIT Log access attempts by principal which require given
permissions.
ARCHIVE_ENTRY_ACL_TYPE_ALARM Trigger a system alarm on access attempts by principal
which require given permissions.

The tag specifies the principal to which the permission applies. Valid values are:
ARCHIVE_ENTRY_ACL_USER The user specified by the name field.
ARCHIVE_ENTRY_ACL_USER_OBJ The owner of the file.
ARCHIVE_ENTRY_ACL_GROUP The group specified by the name field.
ARCHIVE_ENTRY_ACL_GROUP_OBJ The group which owns the file.
ARCHIVE_ENTRY_ACL_EVERYONE Any principal who is not the file owner or a member of
the owning group.

Entries with the ARCHIVE_ENTRY_ACL_USER or ARCHIVE_ENTRY_ACL_GROUP tag store the user and
group name in the name string and optionally the user or group ID in the qualifier integer.

NFSv4 ACE permissions and flags are stored in the same permset bitfield. Some permissions
share the same constant and permission character but have different effect on directories
than on files. The following ACE permissions are supported:
ARCHIVE_ENTRY_ACL_READ_DATA (r)
Read data (file).
ARCHIVE_ENTRY_ACL_LIST_DIRECTORY (r)
List entries (directory).
ARCHIVE_ENTRY_ACL_WRITE_DATA (w)
Write data (file).
ARCHIVE_ENTRY_ACL_ADD_FILE (w)
Create files (directory).
ARCHIVE_ENTRY_ACL_EXECUTE (x)
Execute file or change into a directory.
ARCHIVE_ENTRY_ACL_APPEND_DATA (p)
Append data (file).
ARCHIVE_ENTRY_ACL_ADD_SUBDIRECTORY (p)
Create subdirectories (directory).
ARCHIVE_ENTRY_ACL_DELETE_CHILD (D)
Remove files and subdirectories inside a directory.
ARCHIVE_ENTRY_ACL_DELETE (d)
Remove file or directory.
ARCHIVE_ENTRY_ACL_READ_ATTRIBUTES (a)
Read file or directory attributes.
ARCHIVE_ENTRY_ACL_WRITE_ATTRIBUTES (A)
Write file or directory attributes.
ARCHIVE_ENTRY_ACL_READ_NAMED_ATTRS (R)
Read named file or directory attributes.
ARCHIVE_ENTRY_ACL_WRITE_NAMED_ATTRS (W)
Write named file or directory attributes.
ARCHIVE_ENTRY_ACL_READ_ACL (c)
Read file or directory ACL.
ARCHIVE_ENTRY_ACL_WRITE_ACL (C)
Write file or directory ACL.
ARCHIVE_ENTRY_ACL_WRITE_OWNER (o)
Change owner of a file or directory.
ARCHIVE_ENTRY_ACL_SYNCHRONIZE (s)
Use synchronous I/O.

The following NFSv4 ACL inheritance flags are supported:
ARCHIVE_ENTRY_ACL_ENTRY_FILE_INHERIT (f)
Inherit parent directory ACE to files.
ARCHIVE_ENTRY_ACL_ENTRY_DIRECTORY_INHERIT (d)
Inherit parent directory ACE to subdirectories.
ARCHIVE_ENTRY_ACL_ENTRY_INHERIT_ONLY (i)
Only inherit, do not apply the permission on the directory itself.
ARCHIVE_ENTRY_ACL_ENTRY_NO_PROPAGATE_INHERIT (n)
Do not propagate inherit flags. Only first-level entries inherit ACLs.
ARCHIVE_ENTRY_ACL_ENTRY_SUCCESSFUL_ACCESS (S)
Trigger alarm or audit on successful access.
ARCHIVE_ENTRY_ACL_ENTRY_FAILED_ACCESS (F)
Trigger alarm or audit on failed access.
ARCHIVE_ENTRY_ACL_ENTRY_INHERITED (I)
Mark that ACE was inherited.

Functions
archive_entry_acl_add_entry() and archive_entry_acl_add_entry_w() add a single ACL entry.
For the access ACL and non-extended principals, the classic Unix permissions are updated.
An archive entry cannot contain both POSIX.1e and NFSv4 ACL entries.

archive_entry_acl_clear() removes all ACL entries and resets the enumeration pointer.

archive_entry_acl_count() counts the ACL entries that have the given type mask. type can be
the bitwise-or of
ARCHIVE_ENTRY_ACL_TYPE_ACCESS
ARCHIVE_ENTRY_ACL_TYPE_DEFAULT
for POSIX.1e ACLs and
ARCHIVE_ENTRY_ACL_TYPE_ALLOW
ARCHIVE_ENTRY_ACL_TYPE_DENY
ARCHIVE_ENTRY_ACL_TYPE_AUDIT
ARCHIVE_ENTRY_ACL_TYPE_ALARM
for NFSv4 ACLs. For POSIX.1e ACLs if ARCHIVE_ENTRY_ACL_TYPE_ACCESS is included and at least
one extended ACL entry is found, the three non-extended ACLs are added.

archive_entry_acl_from_text() and archive_entry_acl_from_text_w() add new (or merge with
existing) ACL entries from (wide) text. The argument type may take one of the following
values:
ARCHIVE_ENTRY_ACL_TYPE_ACCESS
ARCHIVE_ENTRY_ACL_TYPE_DEFAULT
ARCHIVE_ENTRY_ACL_TYPE_NFS4
Supports all formats that can be created with archive_entry_acl_to_text() or respectively
archive_entry_acl_to_text_w(). Existing ACL entries are preserved. To get a clean new ACL
from text archive_entry_acl_clear() must be called first. Entries prefixed with “default:”
are treated as ARCHIVE_ENTRY_ACL_TYPE_DEFAULT unless type is ARCHIVE_ENTRY_ACL_TYPE_NFS4.
Invalid entries, non-parseable ACL entries and entries beginning with the ‘#’ character
(comments) are skipped.

archive_entry_acl_next() return the next entry of the ACL list. This functions may only be
called after archive_entry_acl_reset() has indicated the presence of extended ACL entries.

archive_entry_acl_reset() prepare reading the list of ACL entries with
archive_entry_acl_next(). The function returns 0 if no non-extended ACLs are found. In
this case, the access permissions should be obtained by archive_entry_mode(3) or set using
chmod(2). Otherwise, the function returns the same value as archive_entry_acl_count().

archive_entry_acl_to_text() and archive_entry_acl_to_text_w() convert the ACL entries for
the given type into a (wide) string of ACL entries separated by newline. If the pointer
len_p is not NULL, then the function shall return the length of the string (not including
the NULL terminator) in the location pointed to by len_p. The flag argument is a bitwise-
or.

The following flags are effective only on POSIX.1e ACL:
ARCHIVE_ENTRY_ACL_TYPE_ACCESS
Output access ACLs.
ARCHIVE_ENTRY_ACL_TYPE_DEFAULT
Output POSIX.1e default ACLs.
ARCHIVE_ENTRY_ACL_STYLE_MARK_DEFAULT
Prefix each default ACL entry with the word “default:”.
ARCHIVE_ENTRY_ACL_STYLE_SOLARIS
The mask and other ACLs don not contain a double colon.

The following flags are effecive only on NFSv4 ACL:
ARCHIVE_ENTRY_ACL_STYLE_COMPACT
Do not output minus characters for unset permissions and flags in NFSv4 ACL
permission and flag fields.

The following flags are effective on both POSIX.1e and NFSv4 ACL:
ARCHIVE_ENTRY_ACL_STYLE_EXTRA_ID
Add an additional colon-separated field containing the user or group id.
ARCHIVE_ENTRY_ACL_STYLE_SEPARATOR_COMMA
Separate ACL entries with comma instead of newline.

If the archive entry contains NFSv4 ACLs, all types of NFSv4 ACLs are returned. It the
entry contains POSIX.1e ACLs and none of the flags ARCHIVE_ENTRY_ACL_TYPE_ACCESS or
ARCHIVE_ENTRY_ACL_TYPE_DEFAULT are specified, both access and default entries are returned
and default entries are prefixed with “default:”.

archive_entry_acl_types() get ACL entry types contained in an archive entry's ACL. As
POSIX.1e and NFSv4 ACL entries cannot be mixed, this function is a very efficient way to
detect if an ACL already contains POSIX.1e or NFSv4 ACL entries.

RETURN VALUES

     archive_entry_acl_count() and archive_entry_acl_reset() returns the number of ACL entries
     that match the given type mask.  For POSIX.1e ACLS if the type mask includes
     ARCHIVE_ENTRY_ACL_TYPE_ACCESS and at least one extended ACL entry exists, the three classic
     Unix permissions are counted.

     archive_entry_acl_from_text() and archive_entry_acl_from_text_w() return ARCHIVE_OK if all
     entries were successfully parsed and ARCHIVE_WARN if one or more entries were invalid or
     non-parseable.

     archive_entry_acl_next() returns ARCHIVE_OK on success, ARCHIVE_EOF if no more ACL entries
     exist and ARCHIVE_WARN if archive_entry_acl_reset() has not been called first.

     archive_entry_acl_to_text() returns a string representing the ACL entries matching the given
     type and flags on success or NULL on error.

     archive_entry_acl_to_text_w() returns a wide string representing the ACL entries matching
     the given type and flags on success or NULL on error.

     archive_entry_acl_types() returns a bitmask of ACL entry types or 0 if archive entry has no
     ACL entries.

NAME

LIBRARY

SYNOPSIS

DESCRIPTION

RETURN VALUES

SEE ALSO