cr_canseeotheruids(9)

cr_canseeotheruids9

Determine if subjects may see entities with differing user id

Usage

int

cr_canseeotheruids(struct ucred *u1, struct ucred *u2);

Overview

This function is internal. Its functionality is integrated into the function cr_bsd_visible(9), which should be called instead.

This function checks if a subject associated to credentials u1 is denied seeing a subject or object associated to credentials u2 by a policy that requires both credentials to have the same real user ID.

This policy is active if and only if the sysctl(8) variable security.bsd.see_other_uids is set to zero.

As usual, the superuser (effective user ID 0) is exempt from this policy provided that the sysctl(8) variable security.bsd.suser_enabled is non-zero and no active MAC policy explicitly denies the exemption( see priv_check_cred(9)).

Return values

The cr_canseeotheruids() function returns 0 if the policy is disabled, both credentials have the same real user ID, or if u1 has privilege exempting it from the policy. Otherwise, it returns ESRCH.

Releases

Unchanged in 12 releases since FreeBSD 13.3-RELEASE.

  1. 13.3–16.0

From base 16.0-CURRENT-20261027-61c70dc16a79 in FreeBSD 16.0-CURRENT (2026-10-27). Parsed by carta from the page's mdoc source.