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c86ca022eb
kernel access control. Instrument the kernel ACL retrieval and modification system calls to invoke MAC framework entry points to authorize these operations. Obtained from: TrustedBSD Project Sponsored by: DARPA, NAI Labs
858 lines
21 KiB
C
858 lines
21 KiB
C
/*-
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* Copyright (c) 1999-2001 Robert N. M. Watson
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* All rights reserved.
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*
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* This software was developed by Robert Watson for the TrustedBSD Project.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* $FreeBSD$
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*/
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/*
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* Developed by the TrustedBSD Project.
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* Support for POSIX.1e access control lists.
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*/
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#include "opt_mac.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/sysproto.h>
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#include <sys/kernel.h>
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#include <sys/mac.h>
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#include <sys/malloc.h>
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#include <sys/vnode.h>
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#include <sys/lock.h>
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#include <sys/mutex.h>
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#include <sys/namei.h>
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#include <sys/file.h>
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#include <sys/proc.h>
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#include <sys/sysent.h>
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#include <sys/errno.h>
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#include <sys/stat.h>
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#include <sys/acl.h>
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MALLOC_DEFINE(M_ACL, "acl", "access control list");
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static int vacl_set_acl(struct thread *td, struct vnode *vp,
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acl_type_t type, struct acl *aclp);
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static int vacl_get_acl(struct thread *td, struct vnode *vp,
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acl_type_t type, struct acl *aclp);
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static int vacl_aclcheck(struct thread *td, struct vnode *vp,
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acl_type_t type, struct acl *aclp);
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/*
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* Implement a version of vaccess() that understands POSIX.1e ACL semantics.
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* Return 0 on success, else an errno value. Should be merged into
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* vaccess() eventually.
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*/
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int
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vaccess_acl_posix1e(enum vtype type, uid_t file_uid, gid_t file_gid,
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struct acl *acl, mode_t acc_mode, struct ucred *cred, int *privused)
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{
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struct acl_entry *acl_other, *acl_mask;
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mode_t dac_granted;
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mode_t cap_granted;
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mode_t acl_mask_granted;
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int group_matched, i;
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/*
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* Look for a normal, non-privileged way to access the file/directory
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* as requested. If it exists, go with that. Otherwise, attempt
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* to use privileges granted via cap_granted. In some cases,
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* which privileges to use may be ambiguous due to "best match",
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* in which case fall back on first match for the time being.
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*/
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if (privused != NULL)
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*privused = 0;
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/*
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* Determine privileges now, but don't apply until we've found
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* a DAC entry that matches but has failed to allow access.
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*/
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#ifndef CAPABILITIES
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if (suser_cred(cred, PRISON_ROOT) == 0)
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cap_granted = VALLPERM;
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else
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cap_granted = 0;
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#else
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cap_granted = 0;
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if (type == VDIR) {
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if ((acc_mode & VEXEC) && !cap_check(cred, NULL,
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CAP_DAC_READ_SEARCH, PRISON_ROOT))
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cap_granted |= VEXEC;
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} else {
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if ((acc_mode & VEXEC) && !cap_check(cred, NULL,
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CAP_DAC_EXECUTE, PRISON_ROOT))
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cap_granted |= VEXEC;
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}
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if ((acc_mode & VREAD) && !cap_check(cred, NULL, CAP_DAC_READ_SEARCH,
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PRISON_ROOT))
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cap_granted |= VREAD;
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if (((acc_mode & VWRITE) || (acc_mode & VAPPEND)) &&
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!cap_check(cred, NULL, CAP_DAC_WRITE, PRISON_ROOT))
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cap_granted |= (VWRITE | VAPPEND);
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if ((acc_mode & VADMIN) && !cap_check(cred, NULL, CAP_FOWNER,
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PRISON_ROOT))
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cap_granted |= VADMIN;
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#endif /* CAPABILITIES */
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/*
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* The owner matches if the effective uid associated with the
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* credential matches that of the ACL_USER_OBJ entry. While we're
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* doing the first scan, also cache the location of the ACL_MASK
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* and ACL_OTHER entries, preventing some future iterations.
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*/
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acl_mask = acl_other = NULL;
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for (i = 0; i < acl->acl_cnt; i++) {
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switch (acl->acl_entry[i].ae_tag) {
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case ACL_USER_OBJ:
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if (file_uid != cred->cr_uid)
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break;
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dac_granted = 0;
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dac_granted |= VADMIN;
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if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl->acl_entry[i].ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl->acl_entry[i].ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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if ((acc_mode & dac_granted) == acc_mode)
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return (0);
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if ((acc_mode & (dac_granted | cap_granted)) ==
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acc_mode) {
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if (privused != NULL)
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*privused = 1;
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return (0);
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}
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goto error;
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case ACL_MASK:
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acl_mask = &acl->acl_entry[i];
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break;
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case ACL_OTHER:
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acl_other = &acl->acl_entry[i];
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break;
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default:
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break;
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}
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}
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/*
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* An ACL_OTHER entry should always exist in a valid access
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* ACL. If it doesn't, then generate a serious failure. For now,
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* this means a debugging message and EPERM, but in the future
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* should probably be a panic.
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*/
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if (acl_other == NULL) {
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/*
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* XXX This should never happen
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*/
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printf("vaccess_acl_posix1e: ACL_OTHER missing\n");
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return (EPERM);
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}
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/*
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* Checks against ACL_USER, ACL_GROUP_OBJ, and ACL_GROUP fields
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* are masked by an ACL_MASK entry, if any. As such, first identify
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* the ACL_MASK field, then iterate through identifying potential
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* user matches, then group matches. If there is no ACL_MASK,
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* assume that the mask allows all requests to succeed.
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*/
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if (acl_mask != NULL) {
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acl_mask_granted = 0;
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if (acl_mask->ae_perm & ACL_EXECUTE)
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acl_mask_granted |= VEXEC;
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if (acl_mask->ae_perm & ACL_READ)
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acl_mask_granted |= VREAD;
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if (acl_mask->ae_perm & ACL_WRITE)
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acl_mask_granted |= (VWRITE | VAPPEND);
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} else
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acl_mask_granted = VEXEC | VREAD | VWRITE | VAPPEND;
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/*
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* Iterate through user ACL entries. Do checks twice, first
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* without privilege, and then if a match is found but failed,
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* a second time with privilege.
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*/
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/*
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* Check ACL_USER ACL entries.
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*/
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for (i = 0; i < acl->acl_cnt; i++) {
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switch (acl->acl_entry[i].ae_tag) {
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case ACL_USER:
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if (acl->acl_entry[i].ae_id != cred->cr_uid)
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break;
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dac_granted = 0;
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if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl->acl_entry[i].ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl->acl_entry[i].ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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dac_granted &= acl_mask_granted;
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if ((acc_mode & dac_granted) == acc_mode)
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return (0);
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if ((acc_mode & (dac_granted | cap_granted)) !=
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acc_mode)
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goto error;
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if (privused != NULL)
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*privused = 1;
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return (0);
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}
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}
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/*
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* Group match is best-match, not first-match, so find a
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* "best" match. Iterate across, testing each potential group
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* match. Make sure we keep track of whether we found a match
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* or not, so that we know if we should try again with any
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* available privilege, or if we should move on to ACL_OTHER.
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*/
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group_matched = 0;
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for (i = 0; i < acl->acl_cnt; i++) {
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switch (acl->acl_entry[i].ae_tag) {
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case ACL_GROUP_OBJ:
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if (!groupmember(file_gid, cred))
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break;
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dac_granted = 0;
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if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl->acl_entry[i].ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl->acl_entry[i].ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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dac_granted &= acl_mask_granted;
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if ((acc_mode & dac_granted) == acc_mode)
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return (0);
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group_matched = 1;
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break;
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case ACL_GROUP:
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if (!groupmember(acl->acl_entry[i].ae_id, cred))
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break;
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dac_granted = 0;
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if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl->acl_entry[i].ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl->acl_entry[i].ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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dac_granted &= acl_mask_granted;
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if ((acc_mode & dac_granted) == acc_mode)
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return (0);
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group_matched = 1;
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break;
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default:
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break;
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}
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}
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if (group_matched == 1) {
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/*
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* There was a match, but it did not grant rights via
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* pure DAC. Try again, this time with privilege.
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*/
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for (i = 0; i < acl->acl_cnt; i++) {
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switch (acl->acl_entry[i].ae_tag) {
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case ACL_GROUP_OBJ:
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if (!groupmember(file_gid, cred))
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break;
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dac_granted = 0;
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if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl->acl_entry[i].ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl->acl_entry[i].ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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dac_granted &= acl_mask_granted;
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if ((acc_mode & (dac_granted | cap_granted)) !=
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acc_mode)
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break;
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if (privused != NULL)
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*privused = 1;
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return (0);
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case ACL_GROUP:
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if (!groupmember(acl->acl_entry[i].ae_id,
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cred))
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break;
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dac_granted = 0;
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if (acl->acl_entry[i].ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl->acl_entry[i].ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl->acl_entry[i].ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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dac_granted &= acl_mask_granted;
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if ((acc_mode & (dac_granted | cap_granted)) !=
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acc_mode)
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break;
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if (privused != NULL)
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*privused = 1;
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return (0);
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default:
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break;
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}
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}
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/*
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* Even with privilege, group membership was not sufficient.
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* Return failure.
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*/
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goto error;
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}
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/*
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* Fall back on ACL_OTHER. ACL_MASK is not applied to ACL_OTHER.
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*/
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dac_granted = 0;
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if (acl_other->ae_perm & ACL_EXECUTE)
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dac_granted |= VEXEC;
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if (acl_other->ae_perm & ACL_READ)
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dac_granted |= VREAD;
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if (acl_other->ae_perm & ACL_WRITE)
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dac_granted |= (VWRITE | VAPPEND);
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if ((acc_mode & dac_granted) == acc_mode)
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return (0);
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if ((acc_mode & (dac_granted | cap_granted)) == acc_mode) {
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if (privused != NULL)
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*privused = 1;
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return (0);
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}
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error:
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return ((acc_mode & VADMIN) ? EPERM : EACCES);
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}
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/*
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* For the purposes of filesystems maintaining the _OBJ entries in an
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* inode with a mode_t field, this routine converts a mode_t entry
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* to an acl_perm_t.
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*/
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acl_perm_t
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acl_posix1e_mode_to_perm(acl_tag_t tag, mode_t mode)
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{
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acl_perm_t perm = 0;
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switch(tag) {
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case ACL_USER_OBJ:
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if (mode & S_IXUSR)
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perm |= ACL_EXECUTE;
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if (mode & S_IRUSR)
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perm |= ACL_READ;
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if (mode & S_IWUSR)
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perm |= ACL_WRITE;
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return (perm);
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case ACL_GROUP_OBJ:
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if (mode & S_IXGRP)
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perm |= ACL_EXECUTE;
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if (mode & S_IRGRP)
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perm |= ACL_READ;
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if (mode & S_IWGRP)
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perm |= ACL_WRITE;
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return (perm);
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case ACL_OTHER:
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if (mode & S_IXOTH)
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perm |= ACL_EXECUTE;
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if (mode & S_IROTH)
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perm |= ACL_READ;
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if (mode & S_IWOTH)
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perm |= ACL_WRITE;
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return (perm);
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default:
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printf("acl_posix1e_mode_to_perm: invalid tag (%d)\n", tag);
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return (0);
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}
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}
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/*
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* Given inode information (uid, gid, mode), return an acl entry of the
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* appropriate type.
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*/
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struct acl_entry
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acl_posix1e_mode_to_entry(acl_tag_t tag, uid_t uid, gid_t gid, mode_t mode)
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{
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struct acl_entry acl_entry;
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acl_entry.ae_tag = tag;
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acl_entry.ae_perm = acl_posix1e_mode_to_perm(tag, mode);
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switch(tag) {
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case ACL_USER_OBJ:
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acl_entry.ae_id = uid;
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break;
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case ACL_GROUP_OBJ:
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acl_entry.ae_id = gid;
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break;
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case ACL_OTHER:
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acl_entry.ae_id = ACL_UNDEFINED_ID;
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break;
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default:
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acl_entry.ae_id = ACL_UNDEFINED_ID;
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printf("acl_posix1e_mode_to_entry: invalid tag (%d)\n", tag);
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}
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return (acl_entry);
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}
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/*
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* Utility function to generate a file mode given appropriate ACL entries.
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*/
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mode_t
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acl_posix1e_perms_to_mode(struct acl_entry *acl_user_obj_entry,
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struct acl_entry *acl_group_obj_entry, struct acl_entry *acl_other_entry)
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{
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mode_t mode;
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mode = 0;
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if (acl_user_obj_entry->ae_perm & ACL_EXECUTE)
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mode |= S_IXUSR;
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if (acl_user_obj_entry->ae_perm & ACL_READ)
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mode |= S_IRUSR;
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if (acl_user_obj_entry->ae_perm & ACL_WRITE)
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mode |= S_IWUSR;
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if (acl_group_obj_entry->ae_perm & ACL_EXECUTE)
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mode |= S_IXGRP;
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if (acl_group_obj_entry->ae_perm & ACL_READ)
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mode |= S_IRGRP;
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if (acl_group_obj_entry->ae_perm & ACL_WRITE)
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mode |= S_IWGRP;
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if (acl_other_entry->ae_perm & ACL_EXECUTE)
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mode |= S_IXOTH;
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if (acl_other_entry->ae_perm & ACL_READ)
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mode |= S_IROTH;
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if (acl_other_entry->ae_perm & ACL_WRITE)
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mode |= S_IWOTH;
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return (mode);
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}
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/*
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* Perform a syntactic check of the ACL, sufficient to allow an
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* implementing filesystem to determine if it should accept this and
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* rely on the POSIX.1e ACL properties.
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*/
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int
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acl_posix1e_check(struct acl *acl)
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{
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int num_acl_user_obj, num_acl_user, num_acl_group_obj, num_acl_group;
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int num_acl_mask, num_acl_other, i;
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/*
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* Verify that the number of entries does not exceed the maximum
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* defined for acl_t.
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* Verify that the correct number of various sorts of ae_tags are
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* present:
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* Exactly one ACL_USER_OBJ
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* Exactly one ACL_GROUP_OBJ
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* Exactly one ACL_OTHER
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* If any ACL_USER or ACL_GROUP entries appear, then exactly one
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* ACL_MASK entry must also appear.
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* Verify that all ae_perm entries are in ACL_PERM_BITS.
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* Verify all ae_tag entries are understood by this implementation.
|
|
* Note: Does not check for uniqueness of qualifier (ae_id) field.
|
|
*/
|
|
num_acl_user_obj = num_acl_user = num_acl_group_obj = num_acl_group =
|
|
num_acl_mask = num_acl_other = 0;
|
|
if (acl->acl_cnt > ACL_MAX_ENTRIES || acl->acl_cnt < 0)
|
|
return (EINVAL);
|
|
for (i = 0; i < acl->acl_cnt; i++) {
|
|
/*
|
|
* Check for a valid tag.
|
|
*/
|
|
switch(acl->acl_entry[i].ae_tag) {
|
|
case ACL_USER_OBJ:
|
|
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
|
|
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
|
|
return (EINVAL);
|
|
num_acl_user_obj++;
|
|
break;
|
|
case ACL_GROUP_OBJ:
|
|
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
|
|
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
|
|
return (EINVAL);
|
|
num_acl_group_obj++;
|
|
break;
|
|
case ACL_USER:
|
|
if (acl->acl_entry[i].ae_id == ACL_UNDEFINED_ID)
|
|
return (EINVAL);
|
|
num_acl_user++;
|
|
break;
|
|
case ACL_GROUP:
|
|
if (acl->acl_entry[i].ae_id == ACL_UNDEFINED_ID)
|
|
return (EINVAL);
|
|
num_acl_group++;
|
|
break;
|
|
case ACL_OTHER:
|
|
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
|
|
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
|
|
return (EINVAL);
|
|
num_acl_other++;
|
|
break;
|
|
case ACL_MASK:
|
|
acl->acl_entry[i].ae_id = ACL_UNDEFINED_ID; /* XXX */
|
|
if (acl->acl_entry[i].ae_id != ACL_UNDEFINED_ID)
|
|
return (EINVAL);
|
|
num_acl_mask++;
|
|
break;
|
|
default:
|
|
return (EINVAL);
|
|
}
|
|
/*
|
|
* Check for valid perm entries.
|
|
*/
|
|
if ((acl->acl_entry[i].ae_perm | ACL_PERM_BITS) !=
|
|
ACL_PERM_BITS)
|
|
return (EINVAL);
|
|
}
|
|
if ((num_acl_user_obj != 1) || (num_acl_group_obj != 1) ||
|
|
(num_acl_other != 1) || (num_acl_mask != 0 && num_acl_mask != 1))
|
|
return (EINVAL);
|
|
if (((num_acl_group != 0) || (num_acl_user != 0)) &&
|
|
(num_acl_mask != 1))
|
|
return (EINVAL);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* These calls wrap the real vnode operations, and are called by the
|
|
* syscall code once the syscall has converted the path or file
|
|
* descriptor to a vnode (unlocked). The aclp pointer is assumed
|
|
* still to point to userland, so this should not be consumed within
|
|
* the kernel except by syscall code. Other code should directly
|
|
* invoke VOP_{SET,GET}ACL.
|
|
*/
|
|
|
|
/*
|
|
* Given a vnode, set its ACL.
|
|
*/
|
|
static int
|
|
vacl_set_acl(struct thread *td, struct vnode *vp, acl_type_t type,
|
|
struct acl *aclp)
|
|
{
|
|
struct acl inkernacl;
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
error = copyin(aclp, &inkernacl, sizeof(struct acl));
|
|
if (error)
|
|
return(error);
|
|
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
|
|
if (error != 0)
|
|
return (error);
|
|
VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
|
|
#ifdef MAC
|
|
error = mac_check_vnode_setacl(td->td_ucred, vp, type, &inkernacl);
|
|
if (error != 0)
|
|
goto out;
|
|
#endif
|
|
error = VOP_SETACL(vp, type, &inkernacl, td->td_ucred, td);
|
|
#ifdef MAC
|
|
out:
|
|
#endif
|
|
VOP_UNLOCK(vp, 0, td);
|
|
vn_finished_write(mp);
|
|
return(error);
|
|
}
|
|
|
|
/*
|
|
* Given a vnode, get its ACL.
|
|
*/
|
|
static int
|
|
vacl_get_acl(struct thread *td, struct vnode *vp, acl_type_t type,
|
|
struct acl *aclp)
|
|
{
|
|
struct acl inkernelacl;
|
|
int error;
|
|
|
|
VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
|
|
#ifdef MAC
|
|
error = mac_check_vnode_getacl(td->td_ucred, vp, type);
|
|
if (error != 0)
|
|
goto out;
|
|
#endif
|
|
error = VOP_GETACL(vp, type, &inkernelacl, td->td_ucred, td);
|
|
#ifdef MAC
|
|
out:
|
|
#endif
|
|
VOP_UNLOCK(vp, 0, td);
|
|
if (error == 0)
|
|
error = copyout(&inkernelacl, aclp, sizeof(struct acl));
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a vnode, delete its ACL.
|
|
*/
|
|
static int
|
|
vacl_delete(struct thread *td, struct vnode *vp, acl_type_t type)
|
|
{
|
|
struct mount *mp;
|
|
int error;
|
|
|
|
error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
|
|
if (error)
|
|
return (error);
|
|
VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
|
|
vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
|
|
#ifdef MAC
|
|
error = mac_check_vnode_deleteacl(td->td_ucred, vp, type);
|
|
if (error)
|
|
goto out;
|
|
#endif
|
|
error = VOP_SETACL(vp, type, 0, td->td_ucred, td);
|
|
#ifdef MAC
|
|
out:
|
|
#endif
|
|
VOP_UNLOCK(vp, 0, td);
|
|
vn_finished_write(mp);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a vnode, check whether an ACL is appropriate for it
|
|
*/
|
|
static int
|
|
vacl_aclcheck(struct thread *td, struct vnode *vp, acl_type_t type,
|
|
struct acl *aclp)
|
|
{
|
|
struct acl inkernelacl;
|
|
int error;
|
|
|
|
error = copyin(aclp, &inkernelacl, sizeof(struct acl));
|
|
if (error)
|
|
return(error);
|
|
error = VOP_ACLCHECK(vp, type, &inkernelacl, td->td_ucred, td);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* syscalls -- convert the path/fd to a vnode, and call vacl_whatever.
|
|
* Don't need to lock, as the vacl_ code will get/release any locks
|
|
* required.
|
|
*/
|
|
|
|
/*
|
|
* Given a file path, get an ACL for it
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_get_file(struct thread *td, struct __acl_get_file_args *uap)
|
|
{
|
|
struct nameidata nd;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), td);
|
|
error = namei(&nd);
|
|
if (error == 0) {
|
|
error = vacl_get_acl(td, nd.ni_vp, SCARG(uap, type),
|
|
SCARG(uap, aclp));
|
|
NDFREE(&nd, 0);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file path, set an ACL for it
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_set_file(struct thread *td, struct __acl_set_file_args *uap)
|
|
{
|
|
struct nameidata nd;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), td);
|
|
error = namei(&nd);
|
|
if (error == 0) {
|
|
error = vacl_set_acl(td, nd.ni_vp, SCARG(uap, type),
|
|
SCARG(uap, aclp));
|
|
NDFREE(&nd, 0);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file descriptor, get an ACL for it
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_get_fd(struct thread *td, struct __acl_get_fd_args *uap)
|
|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
error = getvnode(td->td_proc->p_fd, SCARG(uap, filedes), &fp);
|
|
if (error == 0) {
|
|
error = vacl_get_acl(td, (struct vnode *)fp->f_data,
|
|
SCARG(uap, type), SCARG(uap, aclp));
|
|
fdrop(fp, td);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file descriptor, set an ACL for it
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_set_fd(struct thread *td, struct __acl_set_fd_args *uap)
|
|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
error = getvnode(td->td_proc->p_fd, SCARG(uap, filedes), &fp);
|
|
if (error == 0) {
|
|
error = vacl_set_acl(td, (struct vnode *)fp->f_data,
|
|
SCARG(uap, type), SCARG(uap, aclp));
|
|
fdrop(fp, td);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file path, delete an ACL from it.
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_delete_file(struct thread *td, struct __acl_delete_file_args *uap)
|
|
{
|
|
struct nameidata nd;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), td);
|
|
error = namei(&nd);
|
|
if (error == 0) {
|
|
error = vacl_delete(td, nd.ni_vp, SCARG(uap, type));
|
|
NDFREE(&nd, 0);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file path, delete an ACL from it.
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_delete_fd(struct thread *td, struct __acl_delete_fd_args *uap)
|
|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
error = getvnode(td->td_proc->p_fd, SCARG(uap, filedes), &fp);
|
|
if (error == 0) {
|
|
error = vacl_delete(td, (struct vnode *)fp->f_data,
|
|
SCARG(uap, type));
|
|
fdrop(fp, td);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file path, check an ACL for it
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_aclcheck_file(struct thread *td, struct __acl_aclcheck_file_args *uap)
|
|
{
|
|
struct nameidata nd;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), td);
|
|
error = namei(&nd);
|
|
if (error == 0) {
|
|
error = vacl_aclcheck(td, nd.ni_vp, SCARG(uap, type),
|
|
SCARG(uap, aclp));
|
|
NDFREE(&nd, 0);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Given a file descriptor, check an ACL for it
|
|
*
|
|
* MPSAFE
|
|
*/
|
|
int
|
|
__acl_aclcheck_fd(struct thread *td, struct __acl_aclcheck_fd_args *uap)
|
|
{
|
|
struct file *fp;
|
|
int error;
|
|
|
|
mtx_lock(&Giant);
|
|
error = getvnode(td->td_proc->p_fd, SCARG(uap, filedes), &fp);
|
|
if (error == 0) {
|
|
error = vacl_aclcheck(td, (struct vnode *)fp->f_data,
|
|
SCARG(uap, type), SCARG(uap, aclp));
|
|
fdrop(fp, td);
|
|
}
|
|
mtx_unlock(&Giant);
|
|
return (error);
|
|
}
|