mirror of
https://github.com/torvalds/linux.git
synced 2024-11-15 00:21:59 +00:00
2e12256b9a
Replace the uid/gid/perm permissions checking on a key with an ACL to allow the SETATTR and SEARCH permissions to be split. This will also allow a greater range of subjects to represented. ============ WHY DO THIS? ============ The problem is that SETATTR and SEARCH cover a slew of actions, not all of which should be grouped together. For SETATTR, this includes actions that are about controlling access to a key: (1) Changing a key's ownership. (2) Changing a key's security information. (3) Setting a keyring's restriction. And actions that are about managing a key's lifetime: (4) Setting an expiry time. (5) Revoking a key. and (proposed) managing a key as part of a cache: (6) Invalidating a key. Managing a key's lifetime doesn't really have anything to do with controlling access to that key. Expiry time is awkward since it's more about the lifetime of the content and so, in some ways goes better with WRITE permission. It can, however, be set unconditionally by a process with an appropriate authorisation token for instantiating a key, and can also be set by the key type driver when a key is instantiated, so lumping it with the access-controlling actions is probably okay. As for SEARCH permission, that currently covers: (1) Finding keys in a keyring tree during a search. (2) Permitting keyrings to be joined. (3) Invalidation. But these don't really belong together either, since these actions really need to be controlled separately. Finally, there are number of special cases to do with granting the administrator special rights to invalidate or clear keys that I would like to handle with the ACL rather than key flags and special checks. =============== WHAT IS CHANGED =============== The SETATTR permission is split to create two new permissions: (1) SET_SECURITY - which allows the key's owner, group and ACL to be changed and a restriction to be placed on a keyring. (2) REVOKE - which allows a key to be revoked. The SEARCH permission is split to create: (1) SEARCH - which allows a keyring to be search and a key to be found. (2) JOIN - which allows a keyring to be joined as a session keyring. (3) INVAL - which allows a key to be invalidated. The WRITE permission is also split to create: (1) WRITE - which allows a key's content to be altered and links to be added, removed and replaced in a keyring. (2) CLEAR - which allows a keyring to be cleared completely. This is split out to make it possible to give just this to an administrator. (3) REVOKE - see above. Keys acquire ACLs which consist of a series of ACEs, and all that apply are unioned together. An ACE specifies a subject, such as: (*) Possessor - permitted to anyone who 'possesses' a key (*) Owner - permitted to the key owner (*) Group - permitted to the key group (*) Everyone - permitted to everyone Note that 'Other' has been replaced with 'Everyone' on the assumption that you wouldn't grant a permit to 'Other' that you wouldn't also grant to everyone else. Further subjects may be made available by later patches. The ACE also specifies a permissions mask. The set of permissions is now: VIEW Can view the key metadata READ Can read the key content WRITE Can update/modify the key content SEARCH Can find the key by searching/requesting LINK Can make a link to the key SET_SECURITY Can change owner, ACL, expiry INVAL Can invalidate REVOKE Can revoke JOIN Can join this keyring CLEAR Can clear this keyring The KEYCTL_SETPERM function is then deprecated. The KEYCTL_SET_TIMEOUT function then is permitted if SET_SECURITY is set, or if the caller has a valid instantiation auth token. The KEYCTL_INVALIDATE function then requires INVAL. The KEYCTL_REVOKE function then requires REVOKE. The KEYCTL_JOIN_SESSION_KEYRING function then requires JOIN to join an existing keyring. The JOIN permission is enabled by default for session keyrings and manually created keyrings only. ====================== BACKWARD COMPATIBILITY ====================== To maintain backward compatibility, KEYCTL_SETPERM will translate the permissions mask it is given into a new ACL for a key - unless KEYCTL_SET_ACL has been called on that key, in which case an error will be returned. It will convert possessor, owner, group and other permissions into separate ACEs, if each portion of the mask is non-zero. SETATTR permission turns on all of INVAL, REVOKE and SET_SECURITY. WRITE permission turns on WRITE, REVOKE and, if a keyring, CLEAR. JOIN is turned on if a keyring is being altered. The KEYCTL_DESCRIBE function translates the ACL back into a permissions mask to return depending on possessor, owner, group and everyone ACEs. It will make the following mappings: (1) INVAL, JOIN -> SEARCH (2) SET_SECURITY -> SETATTR (3) REVOKE -> WRITE if SETATTR isn't already set (4) CLEAR -> WRITE Note that the value subsequently returned by KEYCTL_DESCRIBE may not match the value set with KEYCTL_SETATTR. ======= TESTING ======= This passes the keyutils testsuite for all but a couple of tests: (1) tests/keyctl/dh_compute/badargs: The first wrong-key-type test now returns EOPNOTSUPP rather than ENOKEY as READ permission isn't removed if the type doesn't have ->read(). You still can't actually read the key. (2) tests/keyctl/permitting/valid: The view-other-permissions test doesn't work as Other has been replaced with Everyone in the ACL. Signed-off-by: David Howells <dhowells@redhat.com>
1260 lines
34 KiB
C
1260 lines
34 KiB
C
/*
|
|
* fs/cifs/cifsacl.c
|
|
*
|
|
* Copyright (C) International Business Machines Corp., 2007,2008
|
|
* Author(s): Steve French (sfrench@us.ibm.com)
|
|
*
|
|
* Contains the routines for mapping CIFS/NTFS ACLs
|
|
*
|
|
* This library is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU Lesser General Public License as published
|
|
* by the Free Software Foundation; either version 2.1 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
|
|
* the GNU Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public License
|
|
* along with this library; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/string.h>
|
|
#include <linux/keyctl.h>
|
|
#include <linux/key-type.h>
|
|
#include <keys/user-type.h>
|
|
#include "cifspdu.h"
|
|
#include "cifsglob.h"
|
|
#include "cifsacl.h"
|
|
#include "cifsproto.h"
|
|
#include "cifs_debug.h"
|
|
|
|
static struct key_acl cifs_idmap_key_acl = {
|
|
.usage = REFCOUNT_INIT(1),
|
|
.nr_ace = 2,
|
|
.possessor_viewable = true,
|
|
.aces = {
|
|
KEY_POSSESSOR_ACE(KEY_ACE_VIEW | KEY_ACE_SEARCH | KEY_ACE_READ),
|
|
KEY_OWNER_ACE(KEY_ACE_VIEW),
|
|
}
|
|
};
|
|
|
|
static struct key_acl cifs_idmap_keyring_acl = {
|
|
.usage = REFCOUNT_INIT(1),
|
|
.nr_ace = 2,
|
|
.aces = {
|
|
KEY_POSSESSOR_ACE(KEY_ACE_SEARCH | KEY_ACE_WRITE),
|
|
KEY_OWNER_ACE(KEY_ACE_VIEW | KEY_ACE_READ),
|
|
}
|
|
};
|
|
|
|
/* security id for everyone/world system group */
|
|
static const struct cifs_sid sid_everyone = {
|
|
1, 1, {0, 0, 0, 0, 0, 1}, {0} };
|
|
/* security id for Authenticated Users system group */
|
|
static const struct cifs_sid sid_authusers = {
|
|
1, 1, {0, 0, 0, 0, 0, 5}, {cpu_to_le32(11)} };
|
|
/* group users */
|
|
static const struct cifs_sid sid_user = {1, 2 , {0, 0, 0, 0, 0, 5}, {} };
|
|
|
|
/* S-1-22-1 Unmapped Unix users */
|
|
static const struct cifs_sid sid_unix_users = {1, 1, {0, 0, 0, 0, 0, 22},
|
|
{cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
|
|
|
|
/* S-1-22-2 Unmapped Unix groups */
|
|
static const struct cifs_sid sid_unix_groups = { 1, 1, {0, 0, 0, 0, 0, 22},
|
|
{cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
|
|
|
|
/*
|
|
* See http://technet.microsoft.com/en-us/library/hh509017(v=ws.10).aspx
|
|
*/
|
|
|
|
/* S-1-5-88 MS NFS and Apple style UID/GID/mode */
|
|
|
|
/* S-1-5-88-1 Unix uid */
|
|
static const struct cifs_sid sid_unix_NFS_users = { 1, 2, {0, 0, 0, 0, 0, 5},
|
|
{cpu_to_le32(88),
|
|
cpu_to_le32(1), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
|
|
|
|
/* S-1-5-88-2 Unix gid */
|
|
static const struct cifs_sid sid_unix_NFS_groups = { 1, 2, {0, 0, 0, 0, 0, 5},
|
|
{cpu_to_le32(88),
|
|
cpu_to_le32(2), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
|
|
|
|
/* S-1-5-88-3 Unix mode */
|
|
static const struct cifs_sid sid_unix_NFS_mode = { 1, 2, {0, 0, 0, 0, 0, 5},
|
|
{cpu_to_le32(88),
|
|
cpu_to_le32(3), 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0} };
|
|
|
|
static const struct cred *root_cred;
|
|
|
|
static int
|
|
cifs_idmap_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
|
|
{
|
|
char *payload;
|
|
|
|
/*
|
|
* If the payload is less than or equal to the size of a pointer, then
|
|
* an allocation here is wasteful. Just copy the data directly to the
|
|
* payload.value union member instead.
|
|
*
|
|
* With this however, you must check the datalen before trying to
|
|
* dereference payload.data!
|
|
*/
|
|
if (prep->datalen <= sizeof(key->payload)) {
|
|
key->payload.data[0] = NULL;
|
|
memcpy(&key->payload, prep->data, prep->datalen);
|
|
} else {
|
|
payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL);
|
|
if (!payload)
|
|
return -ENOMEM;
|
|
key->payload.data[0] = payload;
|
|
}
|
|
|
|
key->datalen = prep->datalen;
|
|
return 0;
|
|
}
|
|
|
|
static inline void
|
|
cifs_idmap_key_destroy(struct key *key)
|
|
{
|
|
if (key->datalen > sizeof(key->payload))
|
|
kfree(key->payload.data[0]);
|
|
}
|
|
|
|
static struct key_type cifs_idmap_key_type = {
|
|
.name = "cifs.idmap",
|
|
.instantiate = cifs_idmap_key_instantiate,
|
|
.destroy = cifs_idmap_key_destroy,
|
|
.describe = user_describe,
|
|
};
|
|
|
|
static char *
|
|
sid_to_key_str(struct cifs_sid *sidptr, unsigned int type)
|
|
{
|
|
int i, len;
|
|
unsigned int saval;
|
|
char *sidstr, *strptr;
|
|
unsigned long long id_auth_val;
|
|
|
|
/* 3 bytes for prefix */
|
|
sidstr = kmalloc(3 + SID_STRING_BASE_SIZE +
|
|
(SID_STRING_SUBAUTH_SIZE * sidptr->num_subauth),
|
|
GFP_KERNEL);
|
|
if (!sidstr)
|
|
return sidstr;
|
|
|
|
strptr = sidstr;
|
|
len = sprintf(strptr, "%cs:S-%hhu", type == SIDOWNER ? 'o' : 'g',
|
|
sidptr->revision);
|
|
strptr += len;
|
|
|
|
/* The authority field is a single 48-bit number */
|
|
id_auth_val = (unsigned long long)sidptr->authority[5];
|
|
id_auth_val |= (unsigned long long)sidptr->authority[4] << 8;
|
|
id_auth_val |= (unsigned long long)sidptr->authority[3] << 16;
|
|
id_auth_val |= (unsigned long long)sidptr->authority[2] << 24;
|
|
id_auth_val |= (unsigned long long)sidptr->authority[1] << 32;
|
|
id_auth_val |= (unsigned long long)sidptr->authority[0] << 48;
|
|
|
|
/*
|
|
* MS-DTYP states that if the authority is >= 2^32, then it should be
|
|
* expressed as a hex value.
|
|
*/
|
|
if (id_auth_val <= UINT_MAX)
|
|
len = sprintf(strptr, "-%llu", id_auth_val);
|
|
else
|
|
len = sprintf(strptr, "-0x%llx", id_auth_val);
|
|
|
|
strptr += len;
|
|
|
|
for (i = 0; i < sidptr->num_subauth; ++i) {
|
|
saval = le32_to_cpu(sidptr->sub_auth[i]);
|
|
len = sprintf(strptr, "-%u", saval);
|
|
strptr += len;
|
|
}
|
|
|
|
return sidstr;
|
|
}
|
|
|
|
/*
|
|
* if the two SIDs (roughly equivalent to a UUID for a user or group) are
|
|
* the same returns zero, if they do not match returns non-zero.
|
|
*/
|
|
static int
|
|
compare_sids(const struct cifs_sid *ctsid, const struct cifs_sid *cwsid)
|
|
{
|
|
int i;
|
|
int num_subauth, num_sat, num_saw;
|
|
|
|
if ((!ctsid) || (!cwsid))
|
|
return 1;
|
|
|
|
/* compare the revision */
|
|
if (ctsid->revision != cwsid->revision) {
|
|
if (ctsid->revision > cwsid->revision)
|
|
return 1;
|
|
else
|
|
return -1;
|
|
}
|
|
|
|
/* compare all of the six auth values */
|
|
for (i = 0; i < NUM_AUTHS; ++i) {
|
|
if (ctsid->authority[i] != cwsid->authority[i]) {
|
|
if (ctsid->authority[i] > cwsid->authority[i])
|
|
return 1;
|
|
else
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
/* compare all of the subauth values if any */
|
|
num_sat = ctsid->num_subauth;
|
|
num_saw = cwsid->num_subauth;
|
|
num_subauth = num_sat < num_saw ? num_sat : num_saw;
|
|
if (num_subauth) {
|
|
for (i = 0; i < num_subauth; ++i) {
|
|
if (ctsid->sub_auth[i] != cwsid->sub_auth[i]) {
|
|
if (le32_to_cpu(ctsid->sub_auth[i]) >
|
|
le32_to_cpu(cwsid->sub_auth[i]))
|
|
return 1;
|
|
else
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0; /* sids compare/match */
|
|
}
|
|
|
|
static bool
|
|
is_well_known_sid(const struct cifs_sid *psid, uint32_t *puid, bool is_group)
|
|
{
|
|
int i;
|
|
int num_subauth;
|
|
const struct cifs_sid *pwell_known_sid;
|
|
|
|
if (!psid || (puid == NULL))
|
|
return false;
|
|
|
|
num_subauth = psid->num_subauth;
|
|
|
|
/* check if Mac (or Windows NFS) vs. Samba format for Unix owner SID */
|
|
if (num_subauth == 2) {
|
|
if (is_group)
|
|
pwell_known_sid = &sid_unix_groups;
|
|
else
|
|
pwell_known_sid = &sid_unix_users;
|
|
} else if (num_subauth == 3) {
|
|
if (is_group)
|
|
pwell_known_sid = &sid_unix_NFS_groups;
|
|
else
|
|
pwell_known_sid = &sid_unix_NFS_users;
|
|
} else
|
|
return false;
|
|
|
|
/* compare the revision */
|
|
if (psid->revision != pwell_known_sid->revision)
|
|
return false;
|
|
|
|
/* compare all of the six auth values */
|
|
for (i = 0; i < NUM_AUTHS; ++i) {
|
|
if (psid->authority[i] != pwell_known_sid->authority[i]) {
|
|
cifs_dbg(FYI, "auth %d did not match\n", i);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if (num_subauth == 2) {
|
|
if (psid->sub_auth[0] != pwell_known_sid->sub_auth[0])
|
|
return false;
|
|
|
|
*puid = le32_to_cpu(psid->sub_auth[1]);
|
|
} else /* 3 subauths, ie Windows/Mac style */ {
|
|
*puid = le32_to_cpu(psid->sub_auth[0]);
|
|
if ((psid->sub_auth[0] != pwell_known_sid->sub_auth[0]) ||
|
|
(psid->sub_auth[1] != pwell_known_sid->sub_auth[1]))
|
|
return false;
|
|
|
|
*puid = le32_to_cpu(psid->sub_auth[2]);
|
|
}
|
|
|
|
cifs_dbg(FYI, "Unix UID %d returned from SID\n", *puid);
|
|
return true; /* well known sid found, uid returned */
|
|
}
|
|
|
|
static void
|
|
cifs_copy_sid(struct cifs_sid *dst, const struct cifs_sid *src)
|
|
{
|
|
int i;
|
|
|
|
dst->revision = src->revision;
|
|
dst->num_subauth = min_t(u8, src->num_subauth, SID_MAX_SUB_AUTHORITIES);
|
|
for (i = 0; i < NUM_AUTHS; ++i)
|
|
dst->authority[i] = src->authority[i];
|
|
for (i = 0; i < dst->num_subauth; ++i)
|
|
dst->sub_auth[i] = src->sub_auth[i];
|
|
}
|
|
|
|
static int
|
|
id_to_sid(unsigned int cid, uint sidtype, struct cifs_sid *ssid)
|
|
{
|
|
int rc;
|
|
struct key *sidkey;
|
|
struct cifs_sid *ksid;
|
|
unsigned int ksid_size;
|
|
char desc[3 + 10 + 1]; /* 3 byte prefix + 10 bytes for value + NULL */
|
|
const struct cred *saved_cred;
|
|
|
|
rc = snprintf(desc, sizeof(desc), "%ci:%u",
|
|
sidtype == SIDOWNER ? 'o' : 'g', cid);
|
|
if (rc >= sizeof(desc))
|
|
return -EINVAL;
|
|
|
|
rc = 0;
|
|
saved_cred = override_creds(root_cred);
|
|
sidkey = request_key(&cifs_idmap_key_type, desc, "",
|
|
&cifs_idmap_key_acl);
|
|
if (IS_ERR(sidkey)) {
|
|
rc = -EINVAL;
|
|
cifs_dbg(FYI, "%s: Can't map %cid %u to a SID\n",
|
|
__func__, sidtype == SIDOWNER ? 'u' : 'g', cid);
|
|
goto out_revert_creds;
|
|
} else if (sidkey->datalen < CIFS_SID_BASE_SIZE) {
|
|
rc = -EIO;
|
|
cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu)\n",
|
|
__func__, sidkey->datalen);
|
|
goto invalidate_key;
|
|
}
|
|
|
|
/*
|
|
* A sid is usually too large to be embedded in payload.value, but if
|
|
* there are no subauthorities and the host has 8-byte pointers, then
|
|
* it could be.
|
|
*/
|
|
ksid = sidkey->datalen <= sizeof(sidkey->payload) ?
|
|
(struct cifs_sid *)&sidkey->payload :
|
|
(struct cifs_sid *)sidkey->payload.data[0];
|
|
|
|
ksid_size = CIFS_SID_BASE_SIZE + (ksid->num_subauth * sizeof(__le32));
|
|
if (ksid_size > sidkey->datalen) {
|
|
rc = -EIO;
|
|
cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu, ksid_size=%u)\n",
|
|
__func__, sidkey->datalen, ksid_size);
|
|
goto invalidate_key;
|
|
}
|
|
|
|
cifs_copy_sid(ssid, ksid);
|
|
out_key_put:
|
|
key_put(sidkey);
|
|
out_revert_creds:
|
|
revert_creds(saved_cred);
|
|
return rc;
|
|
|
|
invalidate_key:
|
|
key_invalidate(sidkey);
|
|
goto out_key_put;
|
|
}
|
|
|
|
static int
|
|
sid_to_id(struct cifs_sb_info *cifs_sb, struct cifs_sid *psid,
|
|
struct cifs_fattr *fattr, uint sidtype)
|
|
{
|
|
int rc;
|
|
struct key *sidkey;
|
|
char *sidstr;
|
|
const struct cred *saved_cred;
|
|
kuid_t fuid = cifs_sb->mnt_uid;
|
|
kgid_t fgid = cifs_sb->mnt_gid;
|
|
|
|
/*
|
|
* If we have too many subauthorities, then something is really wrong.
|
|
* Just return an error.
|
|
*/
|
|
if (unlikely(psid->num_subauth > SID_MAX_SUB_AUTHORITIES)) {
|
|
cifs_dbg(FYI, "%s: %u subauthorities is too many!\n",
|
|
__func__, psid->num_subauth);
|
|
return -EIO;
|
|
}
|
|
|
|
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UID_FROM_ACL) {
|
|
uint32_t unix_id;
|
|
bool is_group;
|
|
|
|
if (sidtype != SIDOWNER)
|
|
is_group = true;
|
|
else
|
|
is_group = false;
|
|
|
|
if (is_well_known_sid(psid, &unix_id, is_group) == false)
|
|
goto try_upcall_to_get_id;
|
|
|
|
if (is_group) {
|
|
kgid_t gid;
|
|
gid_t id;
|
|
|
|
id = (gid_t)unix_id;
|
|
gid = make_kgid(&init_user_ns, id);
|
|
if (gid_valid(gid)) {
|
|
fgid = gid;
|
|
goto got_valid_id;
|
|
}
|
|
} else {
|
|
kuid_t uid;
|
|
uid_t id;
|
|
|
|
id = (uid_t)unix_id;
|
|
uid = make_kuid(&init_user_ns, id);
|
|
if (uid_valid(uid)) {
|
|
fuid = uid;
|
|
goto got_valid_id;
|
|
}
|
|
}
|
|
/* If unable to find uid/gid easily from SID try via upcall */
|
|
}
|
|
|
|
try_upcall_to_get_id:
|
|
sidstr = sid_to_key_str(psid, sidtype);
|
|
if (!sidstr)
|
|
return -ENOMEM;
|
|
|
|
saved_cred = override_creds(root_cred);
|
|
sidkey = request_key(&cifs_idmap_key_type, sidstr, "",
|
|
&cifs_idmap_key_acl);
|
|
if (IS_ERR(sidkey)) {
|
|
rc = -EINVAL;
|
|
cifs_dbg(FYI, "%s: Can't map SID %s to a %cid\n",
|
|
__func__, sidstr, sidtype == SIDOWNER ? 'u' : 'g');
|
|
goto out_revert_creds;
|
|
}
|
|
|
|
/*
|
|
* FIXME: Here we assume that uid_t and gid_t are same size. It's
|
|
* probably a safe assumption but might be better to check based on
|
|
* sidtype.
|
|
*/
|
|
BUILD_BUG_ON(sizeof(uid_t) != sizeof(gid_t));
|
|
if (sidkey->datalen != sizeof(uid_t)) {
|
|
rc = -EIO;
|
|
cifs_dbg(FYI, "%s: Downcall contained malformed key (datalen=%hu)\n",
|
|
__func__, sidkey->datalen);
|
|
key_invalidate(sidkey);
|
|
goto out_key_put;
|
|
}
|
|
|
|
if (sidtype == SIDOWNER) {
|
|
kuid_t uid;
|
|
uid_t id;
|
|
memcpy(&id, &sidkey->payload.data[0], sizeof(uid_t));
|
|
uid = make_kuid(&init_user_ns, id);
|
|
if (uid_valid(uid))
|
|
fuid = uid;
|
|
} else {
|
|
kgid_t gid;
|
|
gid_t id;
|
|
memcpy(&id, &sidkey->payload.data[0], sizeof(gid_t));
|
|
gid = make_kgid(&init_user_ns, id);
|
|
if (gid_valid(gid))
|
|
fgid = gid;
|
|
}
|
|
|
|
out_key_put:
|
|
key_put(sidkey);
|
|
out_revert_creds:
|
|
revert_creds(saved_cred);
|
|
kfree(sidstr);
|
|
|
|
/*
|
|
* Note that we return 0 here unconditionally. If the mapping
|
|
* fails then we just fall back to using the mnt_uid/mnt_gid.
|
|
*/
|
|
got_valid_id:
|
|
if (sidtype == SIDOWNER)
|
|
fattr->cf_uid = fuid;
|
|
else
|
|
fattr->cf_gid = fgid;
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
init_cifs_idmap(void)
|
|
{
|
|
struct cred *cred;
|
|
struct key *keyring;
|
|
int ret;
|
|
|
|
cifs_dbg(FYI, "Registering the %s key type\n",
|
|
cifs_idmap_key_type.name);
|
|
|
|
/* create an override credential set with a special thread keyring in
|
|
* which requests are cached
|
|
*
|
|
* this is used to prevent malicious redirections from being installed
|
|
* with add_key().
|
|
*/
|
|
cred = prepare_kernel_cred(NULL);
|
|
if (!cred)
|
|
return -ENOMEM;
|
|
|
|
keyring = keyring_alloc(".cifs_idmap",
|
|
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
|
|
&cifs_idmap_keyring_acl,
|
|
KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
|
|
if (IS_ERR(keyring)) {
|
|
ret = PTR_ERR(keyring);
|
|
goto failed_put_cred;
|
|
}
|
|
|
|
ret = register_key_type(&cifs_idmap_key_type);
|
|
if (ret < 0)
|
|
goto failed_put_key;
|
|
|
|
/* instruct request_key() to use this special keyring as a cache for
|
|
* the results it looks up */
|
|
set_bit(KEY_FLAG_ROOT_CAN_CLEAR, &keyring->flags);
|
|
cred->thread_keyring = keyring;
|
|
cred->jit_keyring = KEY_REQKEY_DEFL_THREAD_KEYRING;
|
|
root_cred = cred;
|
|
|
|
cifs_dbg(FYI, "cifs idmap keyring: %d\n", key_serial(keyring));
|
|
return 0;
|
|
|
|
failed_put_key:
|
|
key_put(keyring);
|
|
failed_put_cred:
|
|
put_cred(cred);
|
|
return ret;
|
|
}
|
|
|
|
void
|
|
exit_cifs_idmap(void)
|
|
{
|
|
key_revoke(root_cred->thread_keyring);
|
|
unregister_key_type(&cifs_idmap_key_type);
|
|
put_cred(root_cred);
|
|
cifs_dbg(FYI, "Unregistered %s key type\n", cifs_idmap_key_type.name);
|
|
}
|
|
|
|
/* copy ntsd, owner sid, and group sid from a security descriptor to another */
|
|
static void copy_sec_desc(const struct cifs_ntsd *pntsd,
|
|
struct cifs_ntsd *pnntsd, __u32 sidsoffset)
|
|
{
|
|
struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
|
|
struct cifs_sid *nowner_sid_ptr, *ngroup_sid_ptr;
|
|
|
|
/* copy security descriptor control portion */
|
|
pnntsd->revision = pntsd->revision;
|
|
pnntsd->type = pntsd->type;
|
|
pnntsd->dacloffset = cpu_to_le32(sizeof(struct cifs_ntsd));
|
|
pnntsd->sacloffset = 0;
|
|
pnntsd->osidoffset = cpu_to_le32(sidsoffset);
|
|
pnntsd->gsidoffset = cpu_to_le32(sidsoffset + sizeof(struct cifs_sid));
|
|
|
|
/* copy owner sid */
|
|
owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
|
|
le32_to_cpu(pntsd->osidoffset));
|
|
nowner_sid_ptr = (struct cifs_sid *)((char *)pnntsd + sidsoffset);
|
|
cifs_copy_sid(nowner_sid_ptr, owner_sid_ptr);
|
|
|
|
/* copy group sid */
|
|
group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
|
|
le32_to_cpu(pntsd->gsidoffset));
|
|
ngroup_sid_ptr = (struct cifs_sid *)((char *)pnntsd + sidsoffset +
|
|
sizeof(struct cifs_sid));
|
|
cifs_copy_sid(ngroup_sid_ptr, group_sid_ptr);
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
/*
|
|
change posix mode to reflect permissions
|
|
pmode is the existing mode (we only want to overwrite part of this
|
|
bits to set can be: S_IRWXU, S_IRWXG or S_IRWXO ie 00700 or 00070 or 00007
|
|
*/
|
|
static void access_flags_to_mode(__le32 ace_flags, int type, umode_t *pmode,
|
|
umode_t *pbits_to_set)
|
|
{
|
|
__u32 flags = le32_to_cpu(ace_flags);
|
|
/* the order of ACEs is important. The canonical order is to begin with
|
|
DENY entries followed by ALLOW, otherwise an allow entry could be
|
|
encountered first, making the subsequent deny entry like "dead code"
|
|
which would be superflous since Windows stops when a match is made
|
|
for the operation you are trying to perform for your user */
|
|
|
|
/* For deny ACEs we change the mask so that subsequent allow access
|
|
control entries do not turn on the bits we are denying */
|
|
if (type == ACCESS_DENIED) {
|
|
if (flags & GENERIC_ALL)
|
|
*pbits_to_set &= ~S_IRWXUGO;
|
|
|
|
if ((flags & GENERIC_WRITE) ||
|
|
((flags & FILE_WRITE_RIGHTS) == FILE_WRITE_RIGHTS))
|
|
*pbits_to_set &= ~S_IWUGO;
|
|
if ((flags & GENERIC_READ) ||
|
|
((flags & FILE_READ_RIGHTS) == FILE_READ_RIGHTS))
|
|
*pbits_to_set &= ~S_IRUGO;
|
|
if ((flags & GENERIC_EXECUTE) ||
|
|
((flags & FILE_EXEC_RIGHTS) == FILE_EXEC_RIGHTS))
|
|
*pbits_to_set &= ~S_IXUGO;
|
|
return;
|
|
} else if (type != ACCESS_ALLOWED) {
|
|
cifs_dbg(VFS, "unknown access control type %d\n", type);
|
|
return;
|
|
}
|
|
/* else ACCESS_ALLOWED type */
|
|
|
|
if (flags & GENERIC_ALL) {
|
|
*pmode |= (S_IRWXUGO & (*pbits_to_set));
|
|
cifs_dbg(NOISY, "all perms\n");
|
|
return;
|
|
}
|
|
if ((flags & GENERIC_WRITE) ||
|
|
((flags & FILE_WRITE_RIGHTS) == FILE_WRITE_RIGHTS))
|
|
*pmode |= (S_IWUGO & (*pbits_to_set));
|
|
if ((flags & GENERIC_READ) ||
|
|
((flags & FILE_READ_RIGHTS) == FILE_READ_RIGHTS))
|
|
*pmode |= (S_IRUGO & (*pbits_to_set));
|
|
if ((flags & GENERIC_EXECUTE) ||
|
|
((flags & FILE_EXEC_RIGHTS) == FILE_EXEC_RIGHTS))
|
|
*pmode |= (S_IXUGO & (*pbits_to_set));
|
|
|
|
cifs_dbg(NOISY, "access flags 0x%x mode now 0x%x\n", flags, *pmode);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
Generate access flags to reflect permissions mode is the existing mode.
|
|
This function is called for every ACE in the DACL whose SID matches
|
|
with either owner or group or everyone.
|
|
*/
|
|
|
|
static void mode_to_access_flags(umode_t mode, umode_t bits_to_use,
|
|
__u32 *pace_flags)
|
|
{
|
|
/* reset access mask */
|
|
*pace_flags = 0x0;
|
|
|
|
/* bits to use are either S_IRWXU or S_IRWXG or S_IRWXO */
|
|
mode &= bits_to_use;
|
|
|
|
/* check for R/W/X UGO since we do not know whose flags
|
|
is this but we have cleared all the bits sans RWX for
|
|
either user or group or other as per bits_to_use */
|
|
if (mode & S_IRUGO)
|
|
*pace_flags |= SET_FILE_READ_RIGHTS;
|
|
if (mode & S_IWUGO)
|
|
*pace_flags |= SET_FILE_WRITE_RIGHTS;
|
|
if (mode & S_IXUGO)
|
|
*pace_flags |= SET_FILE_EXEC_RIGHTS;
|
|
|
|
cifs_dbg(NOISY, "mode: 0x%x, access flags now 0x%x\n",
|
|
mode, *pace_flags);
|
|
return;
|
|
}
|
|
|
|
static __u16 fill_ace_for_sid(struct cifs_ace *pntace,
|
|
const struct cifs_sid *psid, __u64 nmode, umode_t bits)
|
|
{
|
|
int i;
|
|
__u16 size = 0;
|
|
__u32 access_req = 0;
|
|
|
|
pntace->type = ACCESS_ALLOWED;
|
|
pntace->flags = 0x0;
|
|
mode_to_access_flags(nmode, bits, &access_req);
|
|
if (!access_req)
|
|
access_req = SET_MINIMUM_RIGHTS;
|
|
pntace->access_req = cpu_to_le32(access_req);
|
|
|
|
pntace->sid.revision = psid->revision;
|
|
pntace->sid.num_subauth = psid->num_subauth;
|
|
for (i = 0; i < NUM_AUTHS; i++)
|
|
pntace->sid.authority[i] = psid->authority[i];
|
|
for (i = 0; i < psid->num_subauth; i++)
|
|
pntace->sid.sub_auth[i] = psid->sub_auth[i];
|
|
|
|
size = 1 + 1 + 2 + 4 + 1 + 1 + 6 + (psid->num_subauth * 4);
|
|
pntace->size = cpu_to_le16(size);
|
|
|
|
return size;
|
|
}
|
|
|
|
|
|
#ifdef CONFIG_CIFS_DEBUG2
|
|
static void dump_ace(struct cifs_ace *pace, char *end_of_acl)
|
|
{
|
|
int num_subauth;
|
|
|
|
/* validate that we do not go past end of acl */
|
|
|
|
if (le16_to_cpu(pace->size) < 16) {
|
|
cifs_dbg(VFS, "ACE too small %d\n", le16_to_cpu(pace->size));
|
|
return;
|
|
}
|
|
|
|
if (end_of_acl < (char *)pace + le16_to_cpu(pace->size)) {
|
|
cifs_dbg(VFS, "ACL too small to parse ACE\n");
|
|
return;
|
|
}
|
|
|
|
num_subauth = pace->sid.num_subauth;
|
|
if (num_subauth) {
|
|
int i;
|
|
cifs_dbg(FYI, "ACE revision %d num_auth %d type %d flags %d size %d\n",
|
|
pace->sid.revision, pace->sid.num_subauth, pace->type,
|
|
pace->flags, le16_to_cpu(pace->size));
|
|
for (i = 0; i < num_subauth; ++i) {
|
|
cifs_dbg(FYI, "ACE sub_auth[%d]: 0x%x\n",
|
|
i, le32_to_cpu(pace->sid.sub_auth[i]));
|
|
}
|
|
|
|
/* BB add length check to make sure that we do not have huge
|
|
num auths and therefore go off the end */
|
|
}
|
|
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
|
|
static void parse_dacl(struct cifs_acl *pdacl, char *end_of_acl,
|
|
struct cifs_sid *pownersid, struct cifs_sid *pgrpsid,
|
|
struct cifs_fattr *fattr)
|
|
{
|
|
int i;
|
|
int num_aces = 0;
|
|
int acl_size;
|
|
char *acl_base;
|
|
struct cifs_ace **ppace;
|
|
|
|
/* BB need to add parm so we can store the SID BB */
|
|
|
|
if (!pdacl) {
|
|
/* no DACL in the security descriptor, set
|
|
all the permissions for user/group/other */
|
|
fattr->cf_mode |= S_IRWXUGO;
|
|
return;
|
|
}
|
|
|
|
/* validate that we do not go past end of acl */
|
|
if (end_of_acl < (char *)pdacl + le16_to_cpu(pdacl->size)) {
|
|
cifs_dbg(VFS, "ACL too small to parse DACL\n");
|
|
return;
|
|
}
|
|
|
|
cifs_dbg(NOISY, "DACL revision %d size %d num aces %d\n",
|
|
le16_to_cpu(pdacl->revision), le16_to_cpu(pdacl->size),
|
|
le32_to_cpu(pdacl->num_aces));
|
|
|
|
/* reset rwx permissions for user/group/other.
|
|
Also, if num_aces is 0 i.e. DACL has no ACEs,
|
|
user/group/other have no permissions */
|
|
fattr->cf_mode &= ~(S_IRWXUGO);
|
|
|
|
acl_base = (char *)pdacl;
|
|
acl_size = sizeof(struct cifs_acl);
|
|
|
|
num_aces = le32_to_cpu(pdacl->num_aces);
|
|
if (num_aces > 0) {
|
|
umode_t user_mask = S_IRWXU;
|
|
umode_t group_mask = S_IRWXG;
|
|
umode_t other_mask = S_IRWXU | S_IRWXG | S_IRWXO;
|
|
|
|
if (num_aces > ULONG_MAX / sizeof(struct cifs_ace *))
|
|
return;
|
|
ppace = kmalloc_array(num_aces, sizeof(struct cifs_ace *),
|
|
GFP_KERNEL);
|
|
if (!ppace)
|
|
return;
|
|
|
|
for (i = 0; i < num_aces; ++i) {
|
|
ppace[i] = (struct cifs_ace *) (acl_base + acl_size);
|
|
#ifdef CONFIG_CIFS_DEBUG2
|
|
dump_ace(ppace[i], end_of_acl);
|
|
#endif
|
|
if (compare_sids(&(ppace[i]->sid), pownersid) == 0)
|
|
access_flags_to_mode(ppace[i]->access_req,
|
|
ppace[i]->type,
|
|
&fattr->cf_mode,
|
|
&user_mask);
|
|
if (compare_sids(&(ppace[i]->sid), pgrpsid) == 0)
|
|
access_flags_to_mode(ppace[i]->access_req,
|
|
ppace[i]->type,
|
|
&fattr->cf_mode,
|
|
&group_mask);
|
|
if (compare_sids(&(ppace[i]->sid), &sid_everyone) == 0)
|
|
access_flags_to_mode(ppace[i]->access_req,
|
|
ppace[i]->type,
|
|
&fattr->cf_mode,
|
|
&other_mask);
|
|
if (compare_sids(&(ppace[i]->sid), &sid_authusers) == 0)
|
|
access_flags_to_mode(ppace[i]->access_req,
|
|
ppace[i]->type,
|
|
&fattr->cf_mode,
|
|
&other_mask);
|
|
|
|
|
|
/* memcpy((void *)(&(cifscred->aces[i])),
|
|
(void *)ppace[i],
|
|
sizeof(struct cifs_ace)); */
|
|
|
|
acl_base = (char *)ppace[i];
|
|
acl_size = le16_to_cpu(ppace[i]->size);
|
|
}
|
|
|
|
kfree(ppace);
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
|
|
static int set_chmod_dacl(struct cifs_acl *pndacl, struct cifs_sid *pownersid,
|
|
struct cifs_sid *pgrpsid, __u64 nmode)
|
|
{
|
|
u16 size = 0;
|
|
struct cifs_acl *pnndacl;
|
|
|
|
pnndacl = (struct cifs_acl *)((char *)pndacl + sizeof(struct cifs_acl));
|
|
|
|
size += fill_ace_for_sid((struct cifs_ace *) ((char *)pnndacl + size),
|
|
pownersid, nmode, S_IRWXU);
|
|
size += fill_ace_for_sid((struct cifs_ace *)((char *)pnndacl + size),
|
|
pgrpsid, nmode, S_IRWXG);
|
|
size += fill_ace_for_sid((struct cifs_ace *)((char *)pnndacl + size),
|
|
&sid_everyone, nmode, S_IRWXO);
|
|
|
|
pndacl->size = cpu_to_le16(size + sizeof(struct cifs_acl));
|
|
pndacl->num_aces = cpu_to_le32(3);
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
static int parse_sid(struct cifs_sid *psid, char *end_of_acl)
|
|
{
|
|
/* BB need to add parm so we can store the SID BB */
|
|
|
|
/* validate that we do not go past end of ACL - sid must be at least 8
|
|
bytes long (assuming no sub-auths - e.g. the null SID */
|
|
if (end_of_acl < (char *)psid + 8) {
|
|
cifs_dbg(VFS, "ACL too small to parse SID %p\n", psid);
|
|
return -EINVAL;
|
|
}
|
|
|
|
#ifdef CONFIG_CIFS_DEBUG2
|
|
if (psid->num_subauth) {
|
|
int i;
|
|
cifs_dbg(FYI, "SID revision %d num_auth %d\n",
|
|
psid->revision, psid->num_subauth);
|
|
|
|
for (i = 0; i < psid->num_subauth; i++) {
|
|
cifs_dbg(FYI, "SID sub_auth[%d]: 0x%x\n",
|
|
i, le32_to_cpu(psid->sub_auth[i]));
|
|
}
|
|
|
|
/* BB add length check to make sure that we do not have huge
|
|
num auths and therefore go off the end */
|
|
cifs_dbg(FYI, "RID 0x%x\n",
|
|
le32_to_cpu(psid->sub_auth[psid->num_subauth-1]));
|
|
}
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/* Convert CIFS ACL to POSIX form */
|
|
static int parse_sec_desc(struct cifs_sb_info *cifs_sb,
|
|
struct cifs_ntsd *pntsd, int acl_len, struct cifs_fattr *fattr)
|
|
{
|
|
int rc = 0;
|
|
struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
|
|
struct cifs_acl *dacl_ptr; /* no need for SACL ptr */
|
|
char *end_of_acl = ((char *)pntsd) + acl_len;
|
|
__u32 dacloffset;
|
|
|
|
if (pntsd == NULL)
|
|
return -EIO;
|
|
|
|
owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
|
|
le32_to_cpu(pntsd->osidoffset));
|
|
group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
|
|
le32_to_cpu(pntsd->gsidoffset));
|
|
dacloffset = le32_to_cpu(pntsd->dacloffset);
|
|
dacl_ptr = (struct cifs_acl *)((char *)pntsd + dacloffset);
|
|
cifs_dbg(NOISY, "revision %d type 0x%x ooffset 0x%x goffset 0x%x sacloffset 0x%x dacloffset 0x%x\n",
|
|
pntsd->revision, pntsd->type, le32_to_cpu(pntsd->osidoffset),
|
|
le32_to_cpu(pntsd->gsidoffset),
|
|
le32_to_cpu(pntsd->sacloffset), dacloffset);
|
|
/* cifs_dump_mem("owner_sid: ", owner_sid_ptr, 64); */
|
|
rc = parse_sid(owner_sid_ptr, end_of_acl);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s: Error %d parsing Owner SID\n", __func__, rc);
|
|
return rc;
|
|
}
|
|
rc = sid_to_id(cifs_sb, owner_sid_ptr, fattr, SIDOWNER);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s: Error %d mapping Owner SID to uid\n",
|
|
__func__, rc);
|
|
return rc;
|
|
}
|
|
|
|
rc = parse_sid(group_sid_ptr, end_of_acl);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s: Error %d mapping Owner SID to gid\n",
|
|
__func__, rc);
|
|
return rc;
|
|
}
|
|
rc = sid_to_id(cifs_sb, group_sid_ptr, fattr, SIDGROUP);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s: Error %d mapping Group SID to gid\n",
|
|
__func__, rc);
|
|
return rc;
|
|
}
|
|
|
|
if (dacloffset)
|
|
parse_dacl(dacl_ptr, end_of_acl, owner_sid_ptr,
|
|
group_sid_ptr, fattr);
|
|
else
|
|
cifs_dbg(FYI, "no ACL\n"); /* BB grant all or default perms? */
|
|
|
|
return rc;
|
|
}
|
|
|
|
/* Convert permission bits from mode to equivalent CIFS ACL */
|
|
static int build_sec_desc(struct cifs_ntsd *pntsd, struct cifs_ntsd *pnntsd,
|
|
__u32 secdesclen, __u64 nmode, kuid_t uid, kgid_t gid, int *aclflag)
|
|
{
|
|
int rc = 0;
|
|
__u32 dacloffset;
|
|
__u32 ndacloffset;
|
|
__u32 sidsoffset;
|
|
struct cifs_sid *owner_sid_ptr, *group_sid_ptr;
|
|
struct cifs_sid *nowner_sid_ptr, *ngroup_sid_ptr;
|
|
struct cifs_acl *dacl_ptr = NULL; /* no need for SACL ptr */
|
|
struct cifs_acl *ndacl_ptr = NULL; /* no need for SACL ptr */
|
|
|
|
if (nmode != NO_CHANGE_64) { /* chmod */
|
|
owner_sid_ptr = (struct cifs_sid *)((char *)pntsd +
|
|
le32_to_cpu(pntsd->osidoffset));
|
|
group_sid_ptr = (struct cifs_sid *)((char *)pntsd +
|
|
le32_to_cpu(pntsd->gsidoffset));
|
|
dacloffset = le32_to_cpu(pntsd->dacloffset);
|
|
dacl_ptr = (struct cifs_acl *)((char *)pntsd + dacloffset);
|
|
ndacloffset = sizeof(struct cifs_ntsd);
|
|
ndacl_ptr = (struct cifs_acl *)((char *)pnntsd + ndacloffset);
|
|
ndacl_ptr->revision = dacl_ptr->revision;
|
|
ndacl_ptr->size = 0;
|
|
ndacl_ptr->num_aces = 0;
|
|
|
|
rc = set_chmod_dacl(ndacl_ptr, owner_sid_ptr, group_sid_ptr,
|
|
nmode);
|
|
sidsoffset = ndacloffset + le16_to_cpu(ndacl_ptr->size);
|
|
/* copy sec desc control portion & owner and group sids */
|
|
copy_sec_desc(pntsd, pnntsd, sidsoffset);
|
|
*aclflag = CIFS_ACL_DACL;
|
|
} else {
|
|
memcpy(pnntsd, pntsd, secdesclen);
|
|
if (uid_valid(uid)) { /* chown */
|
|
uid_t id;
|
|
owner_sid_ptr = (struct cifs_sid *)((char *)pnntsd +
|
|
le32_to_cpu(pnntsd->osidoffset));
|
|
nowner_sid_ptr = kmalloc(sizeof(struct cifs_sid),
|
|
GFP_KERNEL);
|
|
if (!nowner_sid_ptr)
|
|
return -ENOMEM;
|
|
id = from_kuid(&init_user_ns, uid);
|
|
rc = id_to_sid(id, SIDOWNER, nowner_sid_ptr);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s: Mapping error %d for owner id %d\n",
|
|
__func__, rc, id);
|
|
kfree(nowner_sid_ptr);
|
|
return rc;
|
|
}
|
|
cifs_copy_sid(owner_sid_ptr, nowner_sid_ptr);
|
|
kfree(nowner_sid_ptr);
|
|
*aclflag = CIFS_ACL_OWNER;
|
|
}
|
|
if (gid_valid(gid)) { /* chgrp */
|
|
gid_t id;
|
|
group_sid_ptr = (struct cifs_sid *)((char *)pnntsd +
|
|
le32_to_cpu(pnntsd->gsidoffset));
|
|
ngroup_sid_ptr = kmalloc(sizeof(struct cifs_sid),
|
|
GFP_KERNEL);
|
|
if (!ngroup_sid_ptr)
|
|
return -ENOMEM;
|
|
id = from_kgid(&init_user_ns, gid);
|
|
rc = id_to_sid(id, SIDGROUP, ngroup_sid_ptr);
|
|
if (rc) {
|
|
cifs_dbg(FYI, "%s: Mapping error %d for group id %d\n",
|
|
__func__, rc, id);
|
|
kfree(ngroup_sid_ptr);
|
|
return rc;
|
|
}
|
|
cifs_copy_sid(group_sid_ptr, ngroup_sid_ptr);
|
|
kfree(ngroup_sid_ptr);
|
|
*aclflag = CIFS_ACL_GROUP;
|
|
}
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
struct cifs_ntsd *get_cifs_acl_by_fid(struct cifs_sb_info *cifs_sb,
|
|
const struct cifs_fid *cifsfid, u32 *pacllen)
|
|
{
|
|
struct cifs_ntsd *pntsd = NULL;
|
|
unsigned int xid;
|
|
int rc;
|
|
struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
|
|
|
|
if (IS_ERR(tlink))
|
|
return ERR_CAST(tlink);
|
|
|
|
xid = get_xid();
|
|
rc = CIFSSMBGetCIFSACL(xid, tlink_tcon(tlink), cifsfid->netfid, &pntsd,
|
|
pacllen);
|
|
free_xid(xid);
|
|
|
|
cifs_put_tlink(tlink);
|
|
|
|
cifs_dbg(FYI, "%s: rc = %d ACL len %d\n", __func__, rc, *pacllen);
|
|
if (rc)
|
|
return ERR_PTR(rc);
|
|
return pntsd;
|
|
}
|
|
|
|
static struct cifs_ntsd *get_cifs_acl_by_path(struct cifs_sb_info *cifs_sb,
|
|
const char *path, u32 *pacllen)
|
|
{
|
|
struct cifs_ntsd *pntsd = NULL;
|
|
int oplock = 0;
|
|
unsigned int xid;
|
|
int rc, create_options = 0;
|
|
struct cifs_tcon *tcon;
|
|
struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
|
|
struct cifs_fid fid;
|
|
struct cifs_open_parms oparms;
|
|
|
|
if (IS_ERR(tlink))
|
|
return ERR_CAST(tlink);
|
|
|
|
tcon = tlink_tcon(tlink);
|
|
xid = get_xid();
|
|
|
|
if (backup_cred(cifs_sb))
|
|
create_options |= CREATE_OPEN_BACKUP_INTENT;
|
|
|
|
oparms.tcon = tcon;
|
|
oparms.cifs_sb = cifs_sb;
|
|
oparms.desired_access = READ_CONTROL;
|
|
oparms.create_options = create_options;
|
|
oparms.disposition = FILE_OPEN;
|
|
oparms.path = path;
|
|
oparms.fid = &fid;
|
|
oparms.reconnect = false;
|
|
|
|
rc = CIFS_open(xid, &oparms, &oplock, NULL);
|
|
if (!rc) {
|
|
rc = CIFSSMBGetCIFSACL(xid, tcon, fid.netfid, &pntsd, pacllen);
|
|
CIFSSMBClose(xid, tcon, fid.netfid);
|
|
}
|
|
|
|
cifs_put_tlink(tlink);
|
|
free_xid(xid);
|
|
|
|
cifs_dbg(FYI, "%s: rc = %d ACL len %d\n", __func__, rc, *pacllen);
|
|
if (rc)
|
|
return ERR_PTR(rc);
|
|
return pntsd;
|
|
}
|
|
|
|
/* Retrieve an ACL from the server */
|
|
struct cifs_ntsd *get_cifs_acl(struct cifs_sb_info *cifs_sb,
|
|
struct inode *inode, const char *path,
|
|
u32 *pacllen)
|
|
{
|
|
struct cifs_ntsd *pntsd = NULL;
|
|
struct cifsFileInfo *open_file = NULL;
|
|
|
|
if (inode)
|
|
open_file = find_readable_file(CIFS_I(inode), true);
|
|
if (!open_file)
|
|
return get_cifs_acl_by_path(cifs_sb, path, pacllen);
|
|
|
|
pntsd = get_cifs_acl_by_fid(cifs_sb, &open_file->fid, pacllen);
|
|
cifsFileInfo_put(open_file);
|
|
return pntsd;
|
|
}
|
|
|
|
/* Set an ACL on the server */
|
|
int set_cifs_acl(struct cifs_ntsd *pnntsd, __u32 acllen,
|
|
struct inode *inode, const char *path, int aclflag)
|
|
{
|
|
int oplock = 0;
|
|
unsigned int xid;
|
|
int rc, access_flags, create_options = 0;
|
|
struct cifs_tcon *tcon;
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
|
|
struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
|
|
struct cifs_fid fid;
|
|
struct cifs_open_parms oparms;
|
|
|
|
if (IS_ERR(tlink))
|
|
return PTR_ERR(tlink);
|
|
|
|
tcon = tlink_tcon(tlink);
|
|
xid = get_xid();
|
|
|
|
if (backup_cred(cifs_sb))
|
|
create_options |= CREATE_OPEN_BACKUP_INTENT;
|
|
|
|
if (aclflag == CIFS_ACL_OWNER || aclflag == CIFS_ACL_GROUP)
|
|
access_flags = WRITE_OWNER;
|
|
else
|
|
access_flags = WRITE_DAC;
|
|
|
|
oparms.tcon = tcon;
|
|
oparms.cifs_sb = cifs_sb;
|
|
oparms.desired_access = access_flags;
|
|
oparms.create_options = create_options;
|
|
oparms.disposition = FILE_OPEN;
|
|
oparms.path = path;
|
|
oparms.fid = &fid;
|
|
oparms.reconnect = false;
|
|
|
|
rc = CIFS_open(xid, &oparms, &oplock, NULL);
|
|
if (rc) {
|
|
cifs_dbg(VFS, "Unable to open file to set ACL\n");
|
|
goto out;
|
|
}
|
|
|
|
rc = CIFSSMBSetCIFSACL(xid, tcon, fid.netfid, pnntsd, acllen, aclflag);
|
|
cifs_dbg(NOISY, "SetCIFSACL rc = %d\n", rc);
|
|
|
|
CIFSSMBClose(xid, tcon, fid.netfid);
|
|
out:
|
|
free_xid(xid);
|
|
cifs_put_tlink(tlink);
|
|
return rc;
|
|
}
|
|
|
|
/* Translate the CIFS ACL (similar to NTFS ACL) for a file into mode bits */
|
|
int
|
|
cifs_acl_to_fattr(struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
|
|
struct inode *inode, const char *path,
|
|
const struct cifs_fid *pfid)
|
|
{
|
|
struct cifs_ntsd *pntsd = NULL;
|
|
u32 acllen = 0;
|
|
int rc = 0;
|
|
struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
|
|
struct smb_version_operations *ops;
|
|
|
|
cifs_dbg(NOISY, "converting ACL to mode for %s\n", path);
|
|
|
|
if (IS_ERR(tlink))
|
|
return PTR_ERR(tlink);
|
|
|
|
ops = tlink_tcon(tlink)->ses->server->ops;
|
|
|
|
if (pfid && (ops->get_acl_by_fid))
|
|
pntsd = ops->get_acl_by_fid(cifs_sb, pfid, &acllen);
|
|
else if (ops->get_acl)
|
|
pntsd = ops->get_acl(cifs_sb, inode, path, &acllen);
|
|
else {
|
|
cifs_put_tlink(tlink);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
/* if we can retrieve the ACL, now parse Access Control Entries, ACEs */
|
|
if (IS_ERR(pntsd)) {
|
|
rc = PTR_ERR(pntsd);
|
|
cifs_dbg(VFS, "%s: error %d getting sec desc\n", __func__, rc);
|
|
} else {
|
|
rc = parse_sec_desc(cifs_sb, pntsd, acllen, fattr);
|
|
kfree(pntsd);
|
|
if (rc)
|
|
cifs_dbg(VFS, "parse sec desc failed rc = %d\n", rc);
|
|
}
|
|
|
|
cifs_put_tlink(tlink);
|
|
|
|
return rc;
|
|
}
|
|
|
|
/* Convert mode bits to an ACL so we can update the ACL on the server */
|
|
int
|
|
id_mode_to_cifs_acl(struct inode *inode, const char *path, __u64 nmode,
|
|
kuid_t uid, kgid_t gid)
|
|
{
|
|
int rc = 0;
|
|
int aclflag = CIFS_ACL_DACL; /* default flag to set */
|
|
__u32 secdesclen = 0;
|
|
struct cifs_ntsd *pntsd = NULL; /* acl obtained from server */
|
|
struct cifs_ntsd *pnntsd = NULL; /* modified acl to be sent to server */
|
|
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
|
|
struct tcon_link *tlink = cifs_sb_tlink(cifs_sb);
|
|
struct smb_version_operations *ops;
|
|
|
|
if (IS_ERR(tlink))
|
|
return PTR_ERR(tlink);
|
|
|
|
ops = tlink_tcon(tlink)->ses->server->ops;
|
|
|
|
cifs_dbg(NOISY, "set ACL from mode for %s\n", path);
|
|
|
|
/* Get the security descriptor */
|
|
|
|
if (ops->get_acl == NULL) {
|
|
cifs_put_tlink(tlink);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
pntsd = ops->get_acl(cifs_sb, inode, path, &secdesclen);
|
|
if (IS_ERR(pntsd)) {
|
|
rc = PTR_ERR(pntsd);
|
|
cifs_dbg(VFS, "%s: error %d getting sec desc\n", __func__, rc);
|
|
cifs_put_tlink(tlink);
|
|
return rc;
|
|
}
|
|
|
|
/*
|
|
* Add three ACEs for owner, group, everyone getting rid of other ACEs
|
|
* as chmod disables ACEs and set the security descriptor. Allocate
|
|
* memory for the smb header, set security descriptor request security
|
|
* descriptor parameters, and secuirty descriptor itself
|
|
*/
|
|
secdesclen = max_t(u32, secdesclen, DEFAULT_SEC_DESC_LEN);
|
|
pnntsd = kmalloc(secdesclen, GFP_KERNEL);
|
|
if (!pnntsd) {
|
|
kfree(pntsd);
|
|
cifs_put_tlink(tlink);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
rc = build_sec_desc(pntsd, pnntsd, secdesclen, nmode, uid, gid,
|
|
&aclflag);
|
|
|
|
cifs_dbg(NOISY, "build_sec_desc rc: %d\n", rc);
|
|
|
|
if (ops->set_acl == NULL)
|
|
rc = -EOPNOTSUPP;
|
|
|
|
if (!rc) {
|
|
/* Set the security descriptor */
|
|
rc = ops->set_acl(pnntsd, secdesclen, inode, path, aclflag);
|
|
cifs_dbg(NOISY, "set_cifs_acl rc: %d\n", rc);
|
|
}
|
|
cifs_put_tlink(tlink);
|
|
|
|
kfree(pnntsd);
|
|
kfree(pntsd);
|
|
return rc;
|
|
}
|