xref: /freebsd/share/man/man9/cr_canseejailproc.9 (revision 2008043f386721d58158e37e0d7e50df8095942d)
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26.Dd August 18, 2023
27.Dt CR_CANSEEJAILPROC 9
28.Os
29.Sh NAME
30.Nm cr_canseejailproc
31.Nd determine if subjects may see entities in sub-jails
32.Sh SYNOPSIS
33.Ft int
34.Fn cr_canseejailproc "struct ucred *u1" "struct ucred *u2"
35.Sh DESCRIPTION
36.Bf -emphasis
37This function is internal.
38Its functionality is integrated into the function
39.Xr cr_bsd_visible 9 ,
40which should be called instead.
41.Ef
42.Pp
43This function checks if a subject associated to credentials
44.Fa u1
45is denied seeing a subject or object associated to credentials
46.Fa u2
47by a policy that requires both credentials to be associated to the same jail.
48This is a restriction to the baseline jail policy that a subject can see
49subjects or objects in its own jail or any sub-jail of it.
50.Pp
51This policy is active if and only if the
52.Xr sysctl 8
53variable
54.Va security.bsd.see_jail_proc
55is set to zero.
56.Pp
57As usual, the superuser (effective user ID 0) is exempt from this policy
58provided that the
59.Xr sysctl 8
60variable
61.Va security.bsd.suser_enabled
62is non-zero and no active MAC policy explicitly denies the exemption
63.Po
64see
65.Xr priv_check_cred 9
66.Pc .
67.Sh RETURN VALUES
68The
69.Fn cr_canseejailproc
70function returns 0 if the policy is disabled, both credentials are associated to
71the same jail, or if
72.Fa u1
73has privilege exempting it from the policy.
74Otherwise, it returns
75.Er ESRCH .
76.Sh SEE ALSO
77.Xr cr_bsd_visible 9 ,
78.Xr priv_check_cred 9
79.Sh AUTHORS
80This manual page was written by
81.An Olivier Certner Aq Mt olce.freebsd@certner.fr .
82