mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 19:00:25 +00:00
![Aurelien Aptel](/assets/img/avatar_default.png)
Currently a lot of the code to initialize a connection & session uses the cifs_ses as input. But depending on if we are opening a new session or a new channel we need to use different server pointers. Add a "binding" flag in cifs_ses and a helper function that returns the server ptr a session should use (only in the sess establishment code path). Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
248 lines
6.4 KiB
C
248 lines
6.4 KiB
C
/*
|
|
* fs/cifs/cifs_spnego.c -- SPNEGO upcall management for CIFS
|
|
*
|
|
* Copyright (c) 2007 Red Hat, Inc.
|
|
* Author(s): Jeff Layton (jlayton@redhat.com)
|
|
*
|
|
* 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/list.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/string.h>
|
|
#include <keys/user-type.h>
|
|
#include <linux/key-type.h>
|
|
#include <linux/keyctl.h>
|
|
#include <linux/inet.h>
|
|
#include "cifsglob.h"
|
|
#include "cifs_spnego.h"
|
|
#include "cifs_debug.h"
|
|
#include "cifsproto.h"
|
|
static const struct cred *spnego_cred;
|
|
|
|
/* create a new cifs key */
|
|
static int
|
|
cifs_spnego_key_instantiate(struct key *key, struct key_preparsed_payload *prep)
|
|
{
|
|
char *payload;
|
|
int ret;
|
|
|
|
ret = -ENOMEM;
|
|
payload = kmemdup(prep->data, prep->datalen, GFP_KERNEL);
|
|
if (!payload)
|
|
goto error;
|
|
|
|
/* attach the data */
|
|
key->payload.data[0] = payload;
|
|
ret = 0;
|
|
|
|
error:
|
|
return ret;
|
|
}
|
|
|
|
static void
|
|
cifs_spnego_key_destroy(struct key *key)
|
|
{
|
|
kfree(key->payload.data[0]);
|
|
}
|
|
|
|
|
|
/*
|
|
* keytype for CIFS spnego keys
|
|
*/
|
|
struct key_type cifs_spnego_key_type = {
|
|
.name = "cifs.spnego",
|
|
.instantiate = cifs_spnego_key_instantiate,
|
|
.destroy = cifs_spnego_key_destroy,
|
|
.describe = user_describe,
|
|
};
|
|
|
|
/* length of longest version string e.g. strlen("ver=0xFF") */
|
|
#define MAX_VER_STR_LEN 8
|
|
|
|
/* length of longest security mechanism name, eg in future could have
|
|
* strlen(";sec=ntlmsspi") */
|
|
#define MAX_MECH_STR_LEN 13
|
|
|
|
/* strlen of "host=" */
|
|
#define HOST_KEY_LEN 5
|
|
|
|
/* strlen of ";ip4=" or ";ip6=" */
|
|
#define IP_KEY_LEN 5
|
|
|
|
/* strlen of ";uid=0x" */
|
|
#define UID_KEY_LEN 7
|
|
|
|
/* strlen of ";creduid=0x" */
|
|
#define CREDUID_KEY_LEN 11
|
|
|
|
/* strlen of ";user=" */
|
|
#define USER_KEY_LEN 6
|
|
|
|
/* strlen of ";pid=0x" */
|
|
#define PID_KEY_LEN 7
|
|
|
|
/* get a key struct with a SPNEGO security blob, suitable for session setup */
|
|
struct key *
|
|
cifs_get_spnego_key(struct cifs_ses *sesInfo)
|
|
{
|
|
struct TCP_Server_Info *server = cifs_ses_server(sesInfo);
|
|
struct sockaddr_in *sa = (struct sockaddr_in *) &server->dstaddr;
|
|
struct sockaddr_in6 *sa6 = (struct sockaddr_in6 *) &server->dstaddr;
|
|
char *description, *dp;
|
|
size_t desc_len;
|
|
struct key *spnego_key;
|
|
const char *hostname = server->hostname;
|
|
const struct cred *saved_cred;
|
|
|
|
/* length of fields (with semicolons): ver=0xyz ip4=ipaddress
|
|
host=hostname sec=mechanism uid=0xFF user=username */
|
|
desc_len = MAX_VER_STR_LEN +
|
|
HOST_KEY_LEN + strlen(hostname) +
|
|
IP_KEY_LEN + INET6_ADDRSTRLEN +
|
|
MAX_MECH_STR_LEN +
|
|
UID_KEY_LEN + (sizeof(uid_t) * 2) +
|
|
CREDUID_KEY_LEN + (sizeof(uid_t) * 2) +
|
|
PID_KEY_LEN + (sizeof(pid_t) * 2) + 1;
|
|
|
|
if (sesInfo->user_name)
|
|
desc_len += USER_KEY_LEN + strlen(sesInfo->user_name);
|
|
|
|
spnego_key = ERR_PTR(-ENOMEM);
|
|
description = kzalloc(desc_len, GFP_KERNEL);
|
|
if (description == NULL)
|
|
goto out;
|
|
|
|
dp = description;
|
|
/* start with version and hostname portion of UNC string */
|
|
spnego_key = ERR_PTR(-EINVAL);
|
|
sprintf(dp, "ver=0x%x;host=%s;", CIFS_SPNEGO_UPCALL_VERSION,
|
|
hostname);
|
|
dp = description + strlen(description);
|
|
|
|
/* add the server address */
|
|
if (server->dstaddr.ss_family == AF_INET)
|
|
sprintf(dp, "ip4=%pI4", &sa->sin_addr);
|
|
else if (server->dstaddr.ss_family == AF_INET6)
|
|
sprintf(dp, "ip6=%pI6", &sa6->sin6_addr);
|
|
else
|
|
goto out;
|
|
|
|
dp = description + strlen(description);
|
|
|
|
/* for now, only sec=krb5 and sec=mskrb5 are valid */
|
|
if (server->sec_kerberos)
|
|
sprintf(dp, ";sec=krb5");
|
|
else if (server->sec_mskerberos)
|
|
sprintf(dp, ";sec=mskrb5");
|
|
else {
|
|
cifs_dbg(VFS, "unknown or missing server auth type, use krb5\n");
|
|
sprintf(dp, ";sec=krb5");
|
|
}
|
|
|
|
dp = description + strlen(description);
|
|
sprintf(dp, ";uid=0x%x",
|
|
from_kuid_munged(&init_user_ns, sesInfo->linux_uid));
|
|
|
|
dp = description + strlen(description);
|
|
sprintf(dp, ";creduid=0x%x",
|
|
from_kuid_munged(&init_user_ns, sesInfo->cred_uid));
|
|
|
|
if (sesInfo->user_name) {
|
|
dp = description + strlen(description);
|
|
sprintf(dp, ";user=%s", sesInfo->user_name);
|
|
}
|
|
|
|
dp = description + strlen(description);
|
|
sprintf(dp, ";pid=0x%x", current->pid);
|
|
|
|
cifs_dbg(FYI, "key description = %s\n", description);
|
|
saved_cred = override_creds(spnego_cred);
|
|
spnego_key = request_key(&cifs_spnego_key_type, description, "");
|
|
revert_creds(saved_cred);
|
|
|
|
#ifdef CONFIG_CIFS_DEBUG2
|
|
if (cifsFYI && !IS_ERR(spnego_key)) {
|
|
struct cifs_spnego_msg *msg = spnego_key->payload.data[0];
|
|
cifs_dump_mem("SPNEGO reply blob:", msg->data, min(1024U,
|
|
msg->secblob_len + msg->sesskey_len));
|
|
}
|
|
#endif /* CONFIG_CIFS_DEBUG2 */
|
|
|
|
out:
|
|
kfree(description);
|
|
return spnego_key;
|
|
}
|
|
|
|
int
|
|
init_cifs_spnego(void)
|
|
{
|
|
struct cred *cred;
|
|
struct key *keyring;
|
|
int ret;
|
|
|
|
cifs_dbg(FYI, "Registering the %s key type\n",
|
|
cifs_spnego_key_type.name);
|
|
|
|
/*
|
|
* Create an override credential set with special thread keyring for
|
|
* spnego upcalls.
|
|
*/
|
|
|
|
cred = prepare_kernel_cred(NULL);
|
|
if (!cred)
|
|
return -ENOMEM;
|
|
|
|
keyring = keyring_alloc(".cifs_spnego",
|
|
GLOBAL_ROOT_UID, GLOBAL_ROOT_GID, cred,
|
|
(KEY_POS_ALL & ~KEY_POS_SETATTR) |
|
|
KEY_USR_VIEW | KEY_USR_READ,
|
|
KEY_ALLOC_NOT_IN_QUOTA, NULL, NULL);
|
|
if (IS_ERR(keyring)) {
|
|
ret = PTR_ERR(keyring);
|
|
goto failed_put_cred;
|
|
}
|
|
|
|
ret = register_key_type(&cifs_spnego_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;
|
|
spnego_cred = cred;
|
|
|
|
cifs_dbg(FYI, "cifs spnego 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_spnego(void)
|
|
{
|
|
key_revoke(spnego_cred->thread_keyring);
|
|
unregister_key_type(&cifs_spnego_key_type);
|
|
put_cred(spnego_cred);
|
|
cifs_dbg(FYI, "Unregistered %s key type\n", cifs_spnego_key_type.name);
|
|
}
|