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CR_CANSEEOTHERGIDS(9) FreeBSD Kernel Developer's Manual CR_CANSEEOTHERGIDS(9)
NAME
cr_canseeothergids - determine if subjects may see entities in a disjoint
group set
SYNOPSIS
int
cr_canseeothergids(struct ucred *u1, struct ucred *u2);
DESCRIPTION
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 at least one group in common. For this
determination, the real and supplementary group IDs are used, but not the
effective group IDs, as per realgroupmember(9).
This policy is active if and only if the sysctl(8) variable
security.bsd.see_other_gids 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_canseeothergids() function returns 0 if the policy is disabled,
the credentials share at least one common group, or if u1 has privilege
exempting it from the policy. Otherwise, it returns ESRCH.
SEE ALSO
cr_bsd_visible(9), realgroupmember(9), priv_check_cred(9)
FreeBSD 14.0-RELEASE-p11 August 18, 2023 FreeBSD 14.0-RELEASE-p11