+++ /dev/null
-/*
- * CDDL HEADER START
- *
- * The contents of this file are subject to the terms of the
- * Common Development and Distribution License (the "License").
- * You may not use this file except in compliance with the License.
- *
- * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
- * or http://www.opensolaris.org/os/licensing.
- * See the License for the specific language governing permissions
- * and limitations under the License.
- *
- * When distributing Covered Code, include this CDDL HEADER in each
- * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
- * If applicable, add the following below this CDDL HEADER, with the
- * fields enclosed by brackets "[]" replaced with your own identifying
- * information: Portions Copyright [yyyy] [name of copyright owner]
- *
- * CDDL HEADER END
- */
-
-/*
- * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
- * Copyright 2013, Joyent, Inc. All rights reserved.
- * Copyright (C) 2016 Lawrence Livermore National Security, LLC.
- *
- * For Linux the vast majority of this enforcement is already handled via
- * the standard Linux VFS permission checks. However certain administrative
- * commands which bypass the standard mechanisms may need to make use of
- * this functionality.
- */
-
-#include <sys/policy.h>
-#include <linux/security.h>
-#include <linux/vfs_compat.h>
-
-/*
- * The passed credentials cannot be directly verified because Linux only
- * provides and interface to check the *current* process credentials. In
- * order to handle this the capable() test is only run when the passed
- * credentials match the current process credentials or the kcred. In
- * all other cases this function must fail and return the passed err.
- */
-static int
-priv_policy_ns(const cred_t *cr, int capability, boolean_t all, int err,
- struct user_namespace *ns)
-{
- ASSERT3S(all, ==, B_FALSE);
-
- if (cr != CRED() && (cr != kcred))
- return (err);
-
-#if defined(CONFIG_USER_NS) && defined(HAVE_NS_CAPABLE)
- if (!(ns ? ns_capable(ns, capability) : capable(capability)))
-#else
- if (!capable(capability))
-#endif
- return (err);
-
- return (0);
-}
-
-static int
-priv_policy(const cred_t *cr, int capability, boolean_t all, int err)
-{
- return (priv_policy_ns(cr, capability, all, err, NULL));
-}
-
-static int
-priv_policy_user(const cred_t *cr, int capability, boolean_t all, int err)
-{
- /*
- * All priv_policy_user checks are preceeded by kuid/kgid_has_mapping()
- * checks. If we cannot do them, we shouldn't be using ns_capable()
- * since we don't know whether the affected files are valid in our
- * namespace. Note that kuid_has_mapping() came after cred->user_ns, so
- * we shouldn't need to re-check for HAVE_CRED_USER_NS
- */
-#if defined(CONFIG_USER_NS) && defined(HAVE_KUID_HAS_MAPPING)
- return (priv_policy_ns(cr, capability, all, err, cr->user_ns));
-#else
- return (priv_policy_ns(cr, capability, all, err, NULL));
-#endif
-}
-
-/*
- * Checks for operations that are either client-only or are used by
- * both clients and servers.
- */
-int
-secpolicy_nfs(const cred_t *cr)
-{
- return (priv_policy(cr, CAP_SYS_ADMIN, B_FALSE, EPERM));
-}
-
-/*
- * Catch all system configuration.
- */
-int
-secpolicy_sys_config(const cred_t *cr, boolean_t checkonly)
-{
- return (priv_policy(cr, CAP_SYS_ADMIN, B_FALSE, EPERM));
-}
-
-/*
- * Like secpolicy_vnode_access() but we get the actual wanted mode and the
- * current mode of the file, not the missing bits.
- *
- * Enforced in the Linux VFS.
- */
-int
-secpolicy_vnode_access2(const cred_t *cr, struct inode *ip, uid_t owner,
- mode_t curmode, mode_t wantmode)
-{
- return (0);
-}
-
-/*
- * This is a special routine for ZFS; it is used to determine whether
- * any of the privileges in effect allow any form of access to the
- * file. There's no reason to audit this or any reason to record
- * this. More work is needed to do the "KPLD" stuff.
- */
-int
-secpolicy_vnode_any_access(const cred_t *cr, struct inode *ip, uid_t owner)
-{
- if (crgetfsuid(cr) == owner)
- return (0);
-
- if (zpl_inode_owner_or_capable(ip))
- return (0);
-
-#if defined(CONFIG_USER_NS) && defined(HAVE_KUID_HAS_MAPPING)
- if (!kuid_has_mapping(cr->user_ns, SUID_TO_KUID(owner)))
- return (EPERM);
-#endif
-
- if (priv_policy_user(cr, CAP_DAC_OVERRIDE, B_FALSE, EPERM) == 0)
- return (0);
-
- if (priv_policy_user(cr, CAP_DAC_READ_SEARCH, B_FALSE, EPERM) == 0)
- return (0);
-
- return (EPERM);
-}
-
-/*
- * Determine if subject can chown owner of a file.
- */
-int
-secpolicy_vnode_chown(const cred_t *cr, uid_t owner)
-{
- if (crgetfsuid(cr) == owner)
- return (0);
-
-#if defined(CONFIG_USER_NS) && defined(HAVE_KUID_HAS_MAPPING)
- if (!kuid_has_mapping(cr->user_ns, SUID_TO_KUID(owner)))
- return (EPERM);
-#endif
-
- return (priv_policy_user(cr, CAP_FOWNER, B_FALSE, EPERM));
-}
-
-/*
- * Determine if subject can change group ownership of a file.
- */
-int
-secpolicy_vnode_create_gid(const cred_t *cr)
-{
- return (priv_policy(cr, CAP_SETGID, B_FALSE, EPERM));
-}
-
-/*
- * Policy determines whether we can remove an entry from a directory,
- * regardless of permission bits.
- */
-int
-secpolicy_vnode_remove(const cred_t *cr)
-{
- return (priv_policy(cr, CAP_FOWNER, B_FALSE, EPERM));
-}
-
-/*
- * Determine that subject can modify the mode of a file. allzone privilege
- * needed when modifying root owned object.
- */
-int
-secpolicy_vnode_setdac(const cred_t *cr, uid_t owner)
-{
- if (crgetfsuid(cr) == owner)
- return (0);
-
-#if defined(CONFIG_USER_NS) && defined(HAVE_KUID_HAS_MAPPING)
- if (!kuid_has_mapping(cr->user_ns, SUID_TO_KUID(owner)))
- return (EPERM);
-#endif
-
- return (priv_policy_user(cr, CAP_FOWNER, B_FALSE, EPERM));
-}
-
-/*
- * Are we allowed to retain the set-uid/set-gid bits when
- * changing ownership or when writing to a file?
- * "issuid" should be true when set-uid; only in that case
- * root ownership is checked (setgid is assumed).
- *
- * Enforced in the Linux VFS.
- */
-int
-secpolicy_vnode_setid_retain(const cred_t *cr, boolean_t issuidroot)
-{
- return (0);
-}
-
-/*
- * Determine that subject can set the file setgid flag.
- */
-int
-secpolicy_vnode_setids_setgids(const cred_t *cr, gid_t gid)
-{
-#if defined(CONFIG_USER_NS) && defined(HAVE_KUID_HAS_MAPPING)
- if (!kgid_has_mapping(cr->user_ns, SGID_TO_KGID(gid)))
- return (EPERM);
-#endif
- if (crgetfsgid(cr) != gid && !groupmember(gid, cr))
- return (priv_policy_user(cr, CAP_FSETID, B_FALSE, EPERM));
-
- return (0);
-}
-
-/*
- * Determine if the subject can inject faults in the ZFS fault injection
- * framework. Requires all privileges.
- */
-int
-secpolicy_zinject(const cred_t *cr)
-{
- return (priv_policy(cr, CAP_SYS_ADMIN, B_FALSE, EACCES));
-}
-
-/*
- * Determine if the subject has permission to manipulate ZFS datasets
- * (not pools). Equivalent to the SYS_MOUNT privilege.
- */
-int
-secpolicy_zfs(const cred_t *cr)
-{
- return (priv_policy(cr, CAP_SYS_ADMIN, B_FALSE, EACCES));
-}
-
-void
-secpolicy_setid_clear(vattr_t *vap, cred_t *cr)
-{
- if ((vap->va_mode & (S_ISUID | S_ISGID)) != 0 &&
- secpolicy_vnode_setid_retain(cr,
- (vap->va_mode & S_ISUID) != 0 &&
- (vap->va_mask & AT_UID) != 0 && vap->va_uid == 0) != 0) {
- vap->va_mask |= AT_MODE;
- vap->va_mode &= ~(S_ISUID|S_ISGID);
- }
-}
-
-/*
- * Determine that subject can set the file setid flags.
- */
-static int
-secpolicy_vnode_setid_modify(const cred_t *cr, uid_t owner)
-{
- if (crgetfsuid(cr) == owner)
- return (0);
-
-#if defined(CONFIG_USER_NS) && defined(HAVE_KUID_HAS_MAPPING)
- if (!kuid_has_mapping(cr->user_ns, SUID_TO_KUID(owner)))
- return (EPERM);
-#endif
-
- return (priv_policy_user(cr, CAP_FSETID, B_FALSE, EPERM));
-}
-
-/*
- * Determine that subject can make a file a "sticky".
- *
- * Enforced in the Linux VFS.
- */
-static int
-secpolicy_vnode_stky_modify(const cred_t *cr)
-{
- return (0);
-}
-
-int
-secpolicy_setid_setsticky_clear(struct inode *ip, vattr_t *vap,
- const vattr_t *ovap, cred_t *cr)
-{
- int error;
-
- if ((vap->va_mode & S_ISUID) != 0 &&
- (error = secpolicy_vnode_setid_modify(cr,
- ovap->va_uid)) != 0) {
- return (error);
- }
-
- /*
- * Check privilege if attempting to set the
- * sticky bit on a non-directory.
- */
- if (!S_ISDIR(ip->i_mode) && (vap->va_mode & S_ISVTX) != 0 &&
- secpolicy_vnode_stky_modify(cr) != 0) {
- vap->va_mode &= ~S_ISVTX;
- }
-
- /*
- * Check for privilege if attempting to set the
- * group-id bit.
- */
- if ((vap->va_mode & S_ISGID) != 0 &&
- secpolicy_vnode_setids_setgids(cr, ovap->va_gid) != 0) {
- vap->va_mode &= ~S_ISGID;
- }
-
- return (0);
-}
-
-/*
- * Check privileges for setting xvattr attributes
- */
-int
-secpolicy_xvattr(xvattr_t *xvap, uid_t owner, cred_t *cr, vtype_t vtype)
-{
- return (secpolicy_vnode_chown(cr, owner));
-}
-
-/*
- * Check privileges for setattr attributes.
- *
- * Enforced in the Linux VFS.
- */
-int
-secpolicy_vnode_setattr(cred_t *cr, struct inode *ip, struct vattr *vap,
- const struct vattr *ovap, int flags,
- int unlocked_access(void *, int, cred_t *), void *node)
-{
- return (0);
-}
-
-/*
- * Check privileges for links.
- *
- * Enforced in the Linux VFS.
- */
-int
-secpolicy_basic_link(const cred_t *cr)
-{
- return (0);
-}
projects / mirror_ubuntu-bionic-kernel.git / blobdiff