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CR_CANSEEJAILPROC(9) FreeBSD Kernel Developer's Manual CR_CANSEEJAILPROC(9)
NAME cr_canseejailproc - determine if subjects may see entities in sub-jails
SYNOPSIS int cr_canseejailproc(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 be associated to the same jail. This is a restriction to the baseline jail policy that a subject can see subjects or objects in its own jail or any sub-jail of it.
This policy is active if and only if the sysctl(8) variable security.bsd.see_jail_proc 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_canseejailproc() function returns 0 if the policy is disabled, both credentials are associated to the same jail, or if u1 has privilege exempting it from the policy. Otherwise, it returns ESRCH.
SEE ALSO cr_bsd_visible(9), priv_check_cred(9)
AUTHORS This manual page was written by Olivier Certner <olce.freebsd@certner.fr>.
FreeBSD 14.0-RELEASE-p11 August 18, 2023 FreeBSD 14.0-RELEASE-p11