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4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
23 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright 2013, Joyent, Inc. All rights reserved.
25 * Copyright (C) 2016 Lawrence Livermore National Security, LLC.
27 * For Linux the vast majority of this enforcement is already handled via
28 * the standard Linux VFS permission checks. However certain administrative
29 * commands which bypass the standard mechanisms may need to make use of
33 #include <sys/policy.h>
34 #include <linux/security.h>
35 #include <linux/vfs_compat.h>
38 * The passed credentials cannot be directly verified because Linux only
39 * provides and interface to check the *current* proces credentials. In
40 * order to handle this the capable() test is only run when the passed
41 * credentials match the current process credentials or the kcred. In
42 * all other cases this function must fail and return the passed err.
45 priv_policy(const cred_t
*cr
, int capability
, boolean_t all
, int err
)
47 ASSERT3S(all
, ==, B_FALSE
);
49 if (cr
!= CRED() && (cr
!= kcred
))
52 if (!capable(capability
))
59 * Checks for operations that are either client-only or are used by
60 * both clients and servers.
63 secpolicy_nfs(const cred_t
*cr
)
65 return (priv_policy(cr
, CAP_SYS_ADMIN
, B_FALSE
, EPERM
));
69 * Catch all system configuration.
72 secpolicy_sys_config(const cred_t
*cr
, boolean_t checkonly
)
74 return (priv_policy(cr
, CAP_SYS_ADMIN
, B_FALSE
, EPERM
));
78 * Like secpolicy_vnode_access() but we get the actual wanted mode and the
79 * current mode of the file, not the missing bits.
81 * Enforced in the Linux VFS.
84 secpolicy_vnode_access2(const cred_t
*cr
, struct inode
*ip
, uid_t owner
,
85 mode_t curmode
, mode_t wantmode
)
91 * This is a special routine for ZFS; it is used to determine whether
92 * any of the privileges in effect allow any form of access to the
93 * file. There's no reason to audit this or any reason to record
94 * this. More work is needed to do the "KPLD" stuff.
97 secpolicy_vnode_any_access(const cred_t
*cr
, struct inode
*ip
, uid_t owner
)
99 if (crgetuid(cr
) == owner
)
102 if (zpl_inode_owner_or_capable(ip
))
105 if (priv_policy(cr
, CAP_DAC_OVERRIDE
, B_FALSE
, EPERM
) == 0)
108 if (priv_policy(cr
, CAP_DAC_READ_SEARCH
, B_FALSE
, EPERM
) == 0)
115 * Determine if subject can chown owner of a file.
118 secpolicy_vnode_chown(const cred_t
*cr
, uid_t owner
)
120 if (crgetuid(cr
) == owner
)
123 return (priv_policy(cr
, CAP_FOWNER
, B_FALSE
, EPERM
));
127 * Determine if subject can change group ownership of a file.
130 secpolicy_vnode_create_gid(const cred_t
*cr
)
132 return (priv_policy(cr
, CAP_SETGID
, B_FALSE
, EPERM
));
136 * Policy determines whether we can remove an entry from a directory,
137 * regardless of permission bits.
140 secpolicy_vnode_remove(const cred_t
*cr
)
142 return (priv_policy(cr
, CAP_FOWNER
, B_FALSE
, EPERM
));
146 * Determine that subject can modify the mode of a file. allzone privilege
147 * needed when modifying root owned object.
150 secpolicy_vnode_setdac(const cred_t
*cr
, uid_t owner
)
152 if (crgetuid(cr
) == owner
)
155 return (priv_policy(cr
, CAP_FOWNER
, B_FALSE
, EPERM
));
159 * Are we allowed to retain the set-uid/set-gid bits when
160 * changing ownership or when writing to a file?
161 * "issuid" should be true when set-uid; only in that case
162 * root ownership is checked (setgid is assumed).
164 * Enforced in the Linux VFS.
167 secpolicy_vnode_setid_retain(const cred_t
*cr
, boolean_t issuidroot
)
173 * Determine that subject can set the file setgid flag.
176 secpolicy_vnode_setids_setgids(const cred_t
*cr
, gid_t gid
)
178 if (!groupmember(gid
, cr
))
179 return (priv_policy(cr
, CAP_FSETID
, B_FALSE
, EPERM
));
185 * Determine if the subject can inject faults in the ZFS fault injection
186 * framework. Requires all privileges.
189 secpolicy_zinject(const cred_t
*cr
)
191 return (priv_policy(cr
, CAP_SYS_ADMIN
, B_FALSE
, EACCES
));
195 * Determine if the subject has permission to manipulate ZFS datasets
196 * (not pools). Equivalent to the SYS_MOUNT privilege.
199 secpolicy_zfs(const cred_t
*cr
)
201 return (priv_policy(cr
, CAP_SYS_ADMIN
, B_FALSE
, EACCES
));
205 secpolicy_setid_clear(vattr_t
*vap
, cred_t
*cr
)
207 if ((vap
->va_mode
& (S_ISUID
| S_ISGID
)) != 0 &&
208 secpolicy_vnode_setid_retain(cr
,
209 (vap
->va_mode
& S_ISUID
) != 0 &&
210 (vap
->va_mask
& AT_UID
) != 0 && vap
->va_uid
== 0) != 0) {
211 vap
->va_mask
|= AT_MODE
;
212 vap
->va_mode
&= ~(S_ISUID
|S_ISGID
);
217 * Determine that subject can set the file setid flags.
220 secpolicy_vnode_setid_modify(const cred_t
*cr
, uid_t owner
)
222 if (crgetuid(cr
) == owner
)
225 return (priv_policy(cr
, CAP_FSETID
, B_FALSE
, EPERM
));
229 * Determine that subject can make a file a "sticky".
231 * Enforced in the Linux VFS.
234 secpolicy_vnode_stky_modify(const cred_t
*cr
)
240 secpolicy_setid_setsticky_clear(struct inode
*ip
, vattr_t
*vap
,
241 const vattr_t
*ovap
, cred_t
*cr
)
245 if ((vap
->va_mode
& S_ISUID
) != 0 &&
246 (error
= secpolicy_vnode_setid_modify(cr
,
247 ovap
->va_uid
)) != 0) {
252 * Check privilege if attempting to set the
253 * sticky bit on a non-directory.
255 if (!S_ISDIR(ip
->i_mode
) && (vap
->va_mode
& S_ISVTX
) != 0 &&
256 secpolicy_vnode_stky_modify(cr
) != 0) {
257 vap
->va_mode
&= ~S_ISVTX
;
261 * Check for privilege if attempting to set the
264 if ((vap
->va_mode
& S_ISGID
) != 0 &&
265 secpolicy_vnode_setids_setgids(cr
, ovap
->va_gid
) != 0) {
266 vap
->va_mode
&= ~S_ISGID
;
273 * Check privileges for setting xvattr attributes
276 secpolicy_xvattr(xvattr_t
*xvap
, uid_t owner
, cred_t
*cr
, vtype_t vtype
)
278 return (secpolicy_vnode_chown(cr
, owner
));
282 * Check privileges for setattr attributes.
284 * Enforced in the Linux VFS.
287 secpolicy_vnode_setattr(cred_t
*cr
, struct inode
*ip
, struct vattr
*vap
,
288 const struct vattr
*ovap
, int flags
,
289 int unlocked_access(void *, int, cred_t
*), void *node
)
295 * Check privileges for links.
297 * Enforced in the Linux VFS.
300 secpolicy_basic_link(const cred_t
*cr
)