NAME

acl_valid, acl_valid_fd_np, acl_valid_file_np, acl_valid_link_np — validate an ACL

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <sys/types.h>
#include <sys/acl.h>

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);

DESCRIPTION

These functions check that the ACL referred to by the argument acl is valid. The POSIX.1e routine, acl_valid(), checks assumes ACL_TYPE_EXTENDED, and disregard of the context in which the ACL is to be used. The non-portable forms, acl_valid_fd_np(), acl_valid_file_np(), and acl_valid_link_np() allow an ACL to be checked in the context of a specific acl type, type, and file system object. In environments where additional ACL types are supported than just POSIX.1e, this makes more sense. Whereas acl_valid_file_np() will follow the symlink if the specified path is to a symlink, acl_valid_link_np() will not.

The qualifier field shall be unique among all entries of the same POSIX.1e ACL facility defined tag type. The tag type field shall contain valid values including any implementation-defined values. Validation of the values of the qualifier field is implementation-defined.

The POSIX.1e acl_valid() function may reorder the ACL for the purposes of verification; the non-portable validation functions will not.

RETURN VALUES

Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

ERRORS

If any of the following conditions occur, these functions shall return -1 and set errno to the corresponding value:

[EACCES]

Search permission is denied for a component of the path prefix, or the object exists and the process does not have appropriate access rights.

[EBADF]

The fd argument is not a valid file descriptor.

[EINVAL]

Argument acl does not point to a valid ACL.

One or more of the required ACL entries is not present in acl.

The ACL contains entries that are not unique.

The file system rejects the ACL based on fs-specific semantics issues.

[ENAMETOOLONG]

A component of a pathname exceeded 255 characters, or an entire path name exceeded 1023 characters.

[ENOENT]

The named object does not exist, or the path_p argument points to an empty string.

[ENOMEM]

Insufficient memory available to fulfill request.

[EOPNOTSUPP]

The file system does not support ACL retrieval.

SEE ALSO

acl(3), acl_get(3), acl_init(3), acl_set(3), posix1e(3)

STANDARDS

POSIX.1e is described in IEEE POSIX.1e draft 17.

AUTHORS

Michael Smith
Robert N M Watson