ACL_VALID(3)

🌸 NAME (manual page ACL_VALID(3)) 🌸

okay so bestie, this page is literally about the functions that validate an ACL — acl_valid, acl_valid_fd_np, acl_valid_file_np, and acl_valid_link_np. It’s giving “is this ACL okay?” energy 💅✨

📚 LIBRARY 📚

Standard C Library (libc, -lc) — yep, the standard C library, no cap 🫶

✨ 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 this validity only with POSIX.1e ACL semantics, and irrespective 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. 🦋

For POSIX.1e semantics, the checks include:

• The three required entries (ACL_USER_OBJ, ACL_GROUP_OBJ, and ACL_OTHER) shall exist exactly once in the ACL. If the ACL contains any ACL_USER, ACL_GROUP, or any other implementation-defined entries in the file group class then one ACL_MASK entry shall also be required. The ACL shall contain at most one ACL_MASK entry. 💅
• 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.

🧪 IMPLEMENTATION NOTES 🧪

🚧 bestie, heads up: FreeBSD's support for POSIX.1e interfaces and features is still under development at this time.

🫶 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. periodt. 💖

🚨 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 👀

go read these too bestie, iykyk:

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

📜 STANDARDS 📜

POSIX.1e is described in IEEE POSIX.1e draft 17. Discussion of the draft continues on the cross-platform POSIX.1e implementation mailing list. To join this list, see the FreeBSD POSIX.1e implementation page for more information. 🌈

🕰️ HISTORY 🕰️

POSIX.1e support was introduced in FreeBSD 4.0, and development continues. ⭐

👑 AUTHORS 👑

Robert N M Watson — iconic. 💜

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Debian made this page, it’s dated December 29, 2002, and the manual is ACL_VALID(3) — mwah 💋🎀✨