linux/fs/cifs/sess.c
Aurelien Aptel a249cc8bc2 cifs: fix credit accounting for extra channel
With multichannel, operations like the queries
from "ls -lR" can cause all credits to be used and
errors to be returned since max_credits was not
being set correctly on the secondary channels and
thus the client was requesting 0 credits incorrectly
in some cases (which can lead to not having
enough credits to perform any operation on that
channel).

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
CC: <stable@vger.kernel.org> # v5.8+
Reviewed-by: Shyam Prasad N <sprasad@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 11:35:57 -06:00

1755 lines
47 KiB
C

/*
* fs/cifs/sess.c
*
* SMB/CIFS session setup handling routines
*
* Copyright (c) International Business Machines Corp., 2006, 2009
* Author(s): Steve French (sfrench@us.ibm.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 "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "ntlmssp.h"
#include "nterr.h"
#include <linux/utsname.h>
#include <linux/slab.h>
#include "cifs_spnego.h"
#include "smb2proto.h"
#include "fs_context.h"
static int
cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
struct cifs_server_iface *iface);
bool
is_server_using_iface(struct TCP_Server_Info *server,
struct cifs_server_iface *iface)
{
struct sockaddr_in *i4 = (struct sockaddr_in *)&iface->sockaddr;
struct sockaddr_in6 *i6 = (struct sockaddr_in6 *)&iface->sockaddr;
struct sockaddr_in *s4 = (struct sockaddr_in *)&server->dstaddr;
struct sockaddr_in6 *s6 = (struct sockaddr_in6 *)&server->dstaddr;
if (server->dstaddr.ss_family != iface->sockaddr.ss_family)
return false;
if (server->dstaddr.ss_family == AF_INET) {
if (s4->sin_addr.s_addr != i4->sin_addr.s_addr)
return false;
} else if (server->dstaddr.ss_family == AF_INET6) {
if (memcmp(&s6->sin6_addr, &i6->sin6_addr,
sizeof(i6->sin6_addr)) != 0)
return false;
} else {
/* unknown family.. */
return false;
}
return true;
}
bool is_ses_using_iface(struct cifs_ses *ses, struct cifs_server_iface *iface)
{
int i;
for (i = 0; i < ses->chan_count; i++) {
if (is_server_using_iface(ses->chans[i].server, iface))
return true;
}
return false;
}
/* returns number of channels added */
int cifs_try_adding_channels(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses)
{
int old_chan_count = ses->chan_count;
int left = ses->chan_max - ses->chan_count;
int i = 0;
int rc = 0;
int tries = 0;
struct cifs_server_iface *ifaces = NULL;
size_t iface_count;
if (left <= 0) {
cifs_dbg(FYI,
"ses already at max_channels (%zu), nothing to open\n",
ses->chan_max);
return 0;
}
if (ses->server->dialect < SMB30_PROT_ID) {
cifs_dbg(VFS, "multichannel is not supported on this protocol version, use 3.0 or above\n");
return 0;
}
/*
* Make a copy of the iface list at the time and use that
* instead so as to not hold the iface spinlock for opening
* channels
*/
spin_lock(&ses->iface_lock);
iface_count = ses->iface_count;
if (iface_count <= 0) {
spin_unlock(&ses->iface_lock);
cifs_dbg(VFS, "no iface list available to open channels\n");
return 0;
}
ifaces = kmemdup(ses->iface_list, iface_count*sizeof(*ifaces),
GFP_ATOMIC);
if (!ifaces) {
spin_unlock(&ses->iface_lock);
return 0;
}
spin_unlock(&ses->iface_lock);
/*
* Keep connecting to same, fastest, iface for all channels as
* long as its RSS. Try next fastest one if not RSS or channel
* creation fails.
*/
while (left > 0) {
struct cifs_server_iface *iface;
tries++;
if (tries > 3*ses->chan_max) {
cifs_dbg(FYI, "too many channel open attempts (%d channels left to open)\n",
left);
break;
}
iface = &ifaces[i];
if (is_ses_using_iface(ses, iface) && !iface->rss_capable) {
i = (i+1) % iface_count;
continue;
}
rc = cifs_ses_add_channel(cifs_sb, ses, iface);
if (rc) {
cifs_dbg(FYI, "failed to open extra channel on iface#%d rc=%d\n",
i, rc);
i = (i+1) % iface_count;
continue;
}
cifs_dbg(FYI, "successfully opened new channel on iface#%d\n",
i);
left--;
}
kfree(ifaces);
return ses->chan_count - old_chan_count;
}
/*
* If server is a channel of ses, return the corresponding enclosing
* cifs_chan otherwise return NULL.
*/
struct cifs_chan *
cifs_ses_find_chan(struct cifs_ses *ses, struct TCP_Server_Info *server)
{
int i;
for (i = 0; i < ses->chan_count; i++) {
if (ses->chans[i].server == server)
return &ses->chans[i];
}
return NULL;
}
static int
cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
struct cifs_server_iface *iface)
{
struct cifs_chan *chan;
struct smb3_fs_context ctx = {NULL};
static const char unc_fmt[] = "\\%s\\foo";
char unc[sizeof(unc_fmt)+SERVER_NAME_LEN_WITH_NULL] = {0};
struct sockaddr_in *ipv4 = (struct sockaddr_in *)&iface->sockaddr;
struct sockaddr_in6 *ipv6 = (struct sockaddr_in6 *)&iface->sockaddr;
int rc;
unsigned int xid = get_xid();
if (iface->sockaddr.ss_family == AF_INET)
cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
ses, iface->speed, iface->rdma_capable ? "yes" : "no",
&ipv4->sin_addr);
else
cifs_dbg(FYI, "adding channel to ses %p (speed:%zu bps rdma:%s ip:%pI4)\n",
ses, iface->speed, iface->rdma_capable ? "yes" : "no",
&ipv6->sin6_addr);
/*
* Setup a ctx with mostly the same info as the existing
* session and overwrite it with the requested iface data.
*
* We need to setup at least the fields used for negprot and
* sesssetup.
*
* We only need the ctx here, so we can reuse memory from
* the session and server without caring about memory
* management.
*/
/* Always make new connection for now (TODO?) */
ctx.nosharesock = true;
/* Auth */
ctx.domainauto = ses->domainAuto;
ctx.domainname = ses->domainName;
ctx.username = ses->user_name;
ctx.password = ses->password;
ctx.sectype = ses->sectype;
ctx.sign = ses->sign;
/* UNC and paths */
/* XXX: Use ses->server->hostname? */
sprintf(unc, unc_fmt, ses->ip_addr);
ctx.UNC = unc;
ctx.prepath = "";
/* Reuse same version as master connection */
ctx.vals = ses->server->vals;
ctx.ops = ses->server->ops;
ctx.noblocksnd = ses->server->noblocksnd;
ctx.noautotune = ses->server->noautotune;
ctx.sockopt_tcp_nodelay = ses->server->tcp_nodelay;
ctx.echo_interval = ses->server->echo_interval / HZ;
ctx.max_credits = ses->server->max_credits;
/*
* This will be used for encoding/decoding user/domain/pw
* during sess setup auth.
*/
ctx.local_nls = cifs_sb->local_nls;
/* Use RDMA if possible */
ctx.rdma = iface->rdma_capable;
memcpy(&ctx.dstaddr, &iface->sockaddr, sizeof(struct sockaddr_storage));
/* reuse master con client guid */
memcpy(&ctx.client_guid, ses->server->client_guid,
SMB2_CLIENT_GUID_SIZE);
ctx.use_client_guid = true;
mutex_lock(&ses->session_mutex);
chan = ses->binding_chan = &ses->chans[ses->chan_count];
chan->server = cifs_get_tcp_session(&ctx);
if (IS_ERR(chan->server)) {
rc = PTR_ERR(chan->server);
chan->server = NULL;
goto out;
}
spin_lock(&cifs_tcp_ses_lock);
chan->server->is_channel = true;
spin_unlock(&cifs_tcp_ses_lock);
/*
* We need to allocate the server crypto now as we will need
* to sign packets before we generate the channel signing key
* (we sign with the session key)
*/
rc = smb311_crypto_shash_allocate(chan->server);
if (rc) {
cifs_dbg(VFS, "%s: crypto alloc failed\n", __func__);
goto out;
}
ses->binding = true;
rc = cifs_negotiate_protocol(xid, ses);
if (rc)
goto out;
rc = cifs_setup_session(xid, ses, cifs_sb->local_nls);
if (rc)
goto out;
/* success, put it on the list
* XXX: sharing ses between 2 tcp servers is not possible, the
* way "internal" linked lists works in linux makes element
* only able to belong to one list
*
* the binding session is already established so the rest of
* the code should be able to look it up, no need to add the
* ses to the new server.
*/
ses->chan_count++;
atomic_set(&ses->chan_seq, 0);
out:
ses->binding = false;
ses->binding_chan = NULL;
mutex_unlock(&ses->session_mutex);
if (rc && chan->server)
cifs_put_tcp_session(chan->server, 0);
return rc;
}
static __u32 cifs_ssetup_hdr(struct cifs_ses *ses, SESSION_SETUP_ANDX *pSMB)
{
__u32 capabilities = 0;
/* init fields common to all four types of SessSetup */
/* Note that offsets for first seven fields in req struct are same */
/* in CIFS Specs so does not matter which of 3 forms of struct */
/* that we use in next few lines */
/* Note that header is initialized to zero in header_assemble */
pSMB->req.AndXCommand = 0xFF;
pSMB->req.MaxBufferSize = cpu_to_le16(min_t(u32,
CIFSMaxBufSize + MAX_CIFS_HDR_SIZE - 4,
USHRT_MAX));
pSMB->req.MaxMpxCount = cpu_to_le16(ses->server->maxReq);
pSMB->req.VcNumber = cpu_to_le16(1);
/* Now no need to set SMBFLG_CASELESS or obsolete CANONICAL PATH */
/* BB verify whether signing required on neg or just on auth frame
(and NTLM case) */
capabilities = CAP_LARGE_FILES | CAP_NT_SMBS | CAP_LEVEL_II_OPLOCKS |
CAP_LARGE_WRITE_X | CAP_LARGE_READ_X;
if (ses->server->sign)
pSMB->req.hdr.Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
if (ses->capabilities & CAP_UNICODE) {
pSMB->req.hdr.Flags2 |= SMBFLG2_UNICODE;
capabilities |= CAP_UNICODE;
}
if (ses->capabilities & CAP_STATUS32) {
pSMB->req.hdr.Flags2 |= SMBFLG2_ERR_STATUS;
capabilities |= CAP_STATUS32;
}
if (ses->capabilities & CAP_DFS) {
pSMB->req.hdr.Flags2 |= SMBFLG2_DFS;
capabilities |= CAP_DFS;
}
if (ses->capabilities & CAP_UNIX)
capabilities |= CAP_UNIX;
return capabilities;
}
static void
unicode_oslm_strings(char **pbcc_area, const struct nls_table *nls_cp)
{
char *bcc_ptr = *pbcc_area;
int bytes_ret = 0;
/* Copy OS version */
bytes_ret = cifs_strtoUTF16((__le16 *)bcc_ptr, "Linux version ", 32,
nls_cp);
bcc_ptr += 2 * bytes_ret;
bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, init_utsname()->release,
32, nls_cp);
bcc_ptr += 2 * bytes_ret;
bcc_ptr += 2; /* trailing null */
bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, CIFS_NETWORK_OPSYS,
32, nls_cp);
bcc_ptr += 2 * bytes_ret;
bcc_ptr += 2; /* trailing null */
*pbcc_area = bcc_ptr;
}
static void unicode_domain_string(char **pbcc_area, struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
char *bcc_ptr = *pbcc_area;
int bytes_ret = 0;
/* copy domain */
if (ses->domainName == NULL) {
/* Sending null domain better than using a bogus domain name (as
we did briefly in 2.6.18) since server will use its default */
*bcc_ptr = 0;
*(bcc_ptr+1) = 0;
bytes_ret = 0;
} else
bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->domainName,
CIFS_MAX_DOMAINNAME_LEN, nls_cp);
bcc_ptr += 2 * bytes_ret;
bcc_ptr += 2; /* account for null terminator */
*pbcc_area = bcc_ptr;
}
static void unicode_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
char *bcc_ptr = *pbcc_area;
int bytes_ret = 0;
/* BB FIXME add check that strings total less
than 335 or will need to send them as arrays */
/* unicode strings, must be word aligned before the call */
/* if ((long) bcc_ptr % 2) {
*bcc_ptr = 0;
bcc_ptr++;
} */
/* copy user */
if (ses->user_name == NULL) {
/* null user mount */
*bcc_ptr = 0;
*(bcc_ptr+1) = 0;
} else {
bytes_ret = cifs_strtoUTF16((__le16 *) bcc_ptr, ses->user_name,
CIFS_MAX_USERNAME_LEN, nls_cp);
}
bcc_ptr += 2 * bytes_ret;
bcc_ptr += 2; /* account for null termination */
unicode_domain_string(&bcc_ptr, ses, nls_cp);
unicode_oslm_strings(&bcc_ptr, nls_cp);
*pbcc_area = bcc_ptr;
}
static void ascii_ssetup_strings(char **pbcc_area, struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
char *bcc_ptr = *pbcc_area;
int len;
/* copy user */
/* BB what about null user mounts - check that we do this BB */
/* copy user */
if (ses->user_name != NULL) {
len = strscpy(bcc_ptr, ses->user_name, CIFS_MAX_USERNAME_LEN);
if (WARN_ON_ONCE(len < 0))
len = CIFS_MAX_USERNAME_LEN - 1;
bcc_ptr += len;
}
/* else null user mount */
*bcc_ptr = 0;
bcc_ptr++; /* account for null termination */
/* copy domain */
if (ses->domainName != NULL) {
len = strscpy(bcc_ptr, ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
if (WARN_ON_ONCE(len < 0))
len = CIFS_MAX_DOMAINNAME_LEN - 1;
bcc_ptr += len;
} /* else we will send a null domain name
so the server will default to its own domain */
*bcc_ptr = 0;
bcc_ptr++;
/* BB check for overflow here */
strcpy(bcc_ptr, "Linux version ");
bcc_ptr += strlen("Linux version ");
strcpy(bcc_ptr, init_utsname()->release);
bcc_ptr += strlen(init_utsname()->release) + 1;
strcpy(bcc_ptr, CIFS_NETWORK_OPSYS);
bcc_ptr += strlen(CIFS_NETWORK_OPSYS) + 1;
*pbcc_area = bcc_ptr;
}
static void
decode_unicode_ssetup(char **pbcc_area, int bleft, struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
int len;
char *data = *pbcc_area;
cifs_dbg(FYI, "bleft %d\n", bleft);
kfree(ses->serverOS);
ses->serverOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
cifs_dbg(FYI, "serverOS=%s\n", ses->serverOS);
len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
data += len;
bleft -= len;
if (bleft <= 0)
return;
kfree(ses->serverNOS);
ses->serverNOS = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
cifs_dbg(FYI, "serverNOS=%s\n", ses->serverNOS);
len = (UniStrnlen((wchar_t *) data, bleft / 2) * 2) + 2;
data += len;
bleft -= len;
if (bleft <= 0)
return;
kfree(ses->serverDomain);
ses->serverDomain = cifs_strndup_from_utf16(data, bleft, true, nls_cp);
cifs_dbg(FYI, "serverDomain=%s\n", ses->serverDomain);
return;
}
static void decode_ascii_ssetup(char **pbcc_area, __u16 bleft,
struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
int len;
char *bcc_ptr = *pbcc_area;
cifs_dbg(FYI, "decode sessetup ascii. bleft %d\n", bleft);
len = strnlen(bcc_ptr, bleft);
if (len >= bleft)
return;
kfree(ses->serverOS);
ses->serverOS = kmalloc(len + 1, GFP_KERNEL);
if (ses->serverOS) {
memcpy(ses->serverOS, bcc_ptr, len);
ses->serverOS[len] = 0;
if (strncmp(ses->serverOS, "OS/2", 4) == 0)
cifs_dbg(FYI, "OS/2 server\n");
}
bcc_ptr += len + 1;
bleft -= len + 1;
len = strnlen(bcc_ptr, bleft);
if (len >= bleft)
return;
kfree(ses->serverNOS);
ses->serverNOS = kmalloc(len + 1, GFP_KERNEL);
if (ses->serverNOS) {
memcpy(ses->serverNOS, bcc_ptr, len);
ses->serverNOS[len] = 0;
}
bcc_ptr += len + 1;
bleft -= len + 1;
len = strnlen(bcc_ptr, bleft);
if (len > bleft)
return;
/* No domain field in LANMAN case. Domain is
returned by old servers in the SMB negprot response */
/* BB For newer servers which do not support Unicode,
but thus do return domain here we could add parsing
for it later, but it is not very important */
cifs_dbg(FYI, "ascii: bytes left %d\n", bleft);
}
int decode_ntlmssp_challenge(char *bcc_ptr, int blob_len,
struct cifs_ses *ses)
{
unsigned int tioffset; /* challenge message target info area */
unsigned int tilen; /* challenge message target info area length */
CHALLENGE_MESSAGE *pblob = (CHALLENGE_MESSAGE *)bcc_ptr;
if (blob_len < sizeof(CHALLENGE_MESSAGE)) {
cifs_dbg(VFS, "challenge blob len %d too small\n", blob_len);
return -EINVAL;
}
if (memcmp(pblob->Signature, "NTLMSSP", 8)) {
cifs_dbg(VFS, "blob signature incorrect %s\n",
pblob->Signature);
return -EINVAL;
}
if (pblob->MessageType != NtLmChallenge) {
cifs_dbg(VFS, "Incorrect message type %d\n",
pblob->MessageType);
return -EINVAL;
}
memcpy(ses->ntlmssp->cryptkey, pblob->Challenge, CIFS_CRYPTO_KEY_SIZE);
/* BB we could decode pblob->NegotiateFlags; some may be useful */
/* In particular we can examine sign flags */
/* BB spec says that if AvId field of MsvAvTimestamp is populated then
we must set the MIC field of the AUTHENTICATE_MESSAGE */
ses->ntlmssp->server_flags = le32_to_cpu(pblob->NegotiateFlags);
tioffset = le32_to_cpu(pblob->TargetInfoArray.BufferOffset);
tilen = le16_to_cpu(pblob->TargetInfoArray.Length);
if (tioffset > blob_len || tioffset + tilen > blob_len) {
cifs_dbg(VFS, "tioffset + tilen too high %u + %u\n",
tioffset, tilen);
return -EINVAL;
}
if (tilen) {
ses->auth_key.response = kmemdup(bcc_ptr + tioffset, tilen,
GFP_KERNEL);
if (!ses->auth_key.response) {
cifs_dbg(VFS, "Challenge target info alloc failure\n");
return -ENOMEM;
}
ses->auth_key.len = tilen;
}
return 0;
}
/* BB Move to ntlmssp.c eventually */
/* We do not malloc the blob, it is passed in pbuffer, because
it is fixed size, and small, making this approach cleaner */
void build_ntlmssp_negotiate_blob(unsigned char *pbuffer,
struct cifs_ses *ses)
{
struct TCP_Server_Info *server = cifs_ses_server(ses);
NEGOTIATE_MESSAGE *sec_blob = (NEGOTIATE_MESSAGE *)pbuffer;
__u32 flags;
memset(pbuffer, 0, sizeof(NEGOTIATE_MESSAGE));
memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
sec_blob->MessageType = NtLmNegotiate;
/* BB is NTLMV2 session security format easier to use here? */
flags = NTLMSSP_NEGOTIATE_56 | NTLMSSP_REQUEST_TARGET |
NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
NTLMSSP_NEGOTIATE_SEAL;
if (server->sign)
flags |= NTLMSSP_NEGOTIATE_SIGN;
if (!server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
sec_blob->NegotiateFlags = cpu_to_le32(flags);
sec_blob->WorkstationName.BufferOffset = 0;
sec_blob->WorkstationName.Length = 0;
sec_blob->WorkstationName.MaximumLength = 0;
/* Domain name is sent on the Challenge not Negotiate NTLMSSP request */
sec_blob->DomainName.BufferOffset = 0;
sec_blob->DomainName.Length = 0;
sec_blob->DomainName.MaximumLength = 0;
}
static int size_of_ntlmssp_blob(struct cifs_ses *ses)
{
int sz = sizeof(AUTHENTICATE_MESSAGE) + ses->auth_key.len
- CIFS_SESS_KEY_SIZE + CIFS_CPHTXT_SIZE + 2;
if (ses->domainName)
sz += 2 * strnlen(ses->domainName, CIFS_MAX_DOMAINNAME_LEN);
else
sz += 2;
if (ses->user_name)
sz += 2 * strnlen(ses->user_name, CIFS_MAX_USERNAME_LEN);
else
sz += 2;
return sz;
}
int build_ntlmssp_auth_blob(unsigned char **pbuffer,
u16 *buflen,
struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
int rc;
AUTHENTICATE_MESSAGE *sec_blob;
__u32 flags;
unsigned char *tmp;
rc = setup_ntlmv2_rsp(ses, nls_cp);
if (rc) {
cifs_dbg(VFS, "Error %d during NTLMSSP authentication\n", rc);
*buflen = 0;
goto setup_ntlmv2_ret;
}
*pbuffer = kmalloc(size_of_ntlmssp_blob(ses), GFP_KERNEL);
if (!*pbuffer) {
rc = -ENOMEM;
cifs_dbg(VFS, "Error %d during NTLMSSP allocation\n", rc);
*buflen = 0;
goto setup_ntlmv2_ret;
}
sec_blob = (AUTHENTICATE_MESSAGE *)*pbuffer;
memcpy(sec_blob->Signature, NTLMSSP_SIGNATURE, 8);
sec_blob->MessageType = NtLmAuthenticate;
flags = NTLMSSP_NEGOTIATE_56 |
NTLMSSP_REQUEST_TARGET | NTLMSSP_NEGOTIATE_TARGET_INFO |
NTLMSSP_NEGOTIATE_128 | NTLMSSP_NEGOTIATE_UNICODE |
NTLMSSP_NEGOTIATE_NTLM | NTLMSSP_NEGOTIATE_EXTENDED_SEC |
NTLMSSP_NEGOTIATE_SEAL;
if (ses->server->sign)
flags |= NTLMSSP_NEGOTIATE_SIGN;
if (!ses->server->session_estab || ses->ntlmssp->sesskey_per_smbsess)
flags |= NTLMSSP_NEGOTIATE_KEY_XCH;
tmp = *pbuffer + sizeof(AUTHENTICATE_MESSAGE);
sec_blob->NegotiateFlags = cpu_to_le32(flags);
sec_blob->LmChallengeResponse.BufferOffset =
cpu_to_le32(sizeof(AUTHENTICATE_MESSAGE));
sec_blob->LmChallengeResponse.Length = 0;
sec_blob->LmChallengeResponse.MaximumLength = 0;
sec_blob->NtChallengeResponse.BufferOffset =
cpu_to_le32(tmp - *pbuffer);
if (ses->user_name != NULL) {
memcpy(tmp, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
ses->auth_key.len - CIFS_SESS_KEY_SIZE);
tmp += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
sec_blob->NtChallengeResponse.Length =
cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
sec_blob->NtChallengeResponse.MaximumLength =
cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
} else {
/*
* don't send an NT Response for anonymous access
*/
sec_blob->NtChallengeResponse.Length = 0;
sec_blob->NtChallengeResponse.MaximumLength = 0;
}
if (ses->domainName == NULL) {
sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->DomainName.Length = 0;
sec_blob->DomainName.MaximumLength = 0;
tmp += 2;
} else {
int len;
len = cifs_strtoUTF16((__le16 *)tmp, ses->domainName,
CIFS_MAX_DOMAINNAME_LEN, nls_cp);
len *= 2; /* unicode is 2 bytes each */
sec_blob->DomainName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->DomainName.Length = cpu_to_le16(len);
sec_blob->DomainName.MaximumLength = cpu_to_le16(len);
tmp += len;
}
if (ses->user_name == NULL) {
sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->UserName.Length = 0;
sec_blob->UserName.MaximumLength = 0;
tmp += 2;
} else {
int len;
len = cifs_strtoUTF16((__le16 *)tmp, ses->user_name,
CIFS_MAX_USERNAME_LEN, nls_cp);
len *= 2; /* unicode is 2 bytes each */
sec_blob->UserName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->UserName.Length = cpu_to_le16(len);
sec_blob->UserName.MaximumLength = cpu_to_le16(len);
tmp += len;
}
sec_blob->WorkstationName.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->WorkstationName.Length = 0;
sec_blob->WorkstationName.MaximumLength = 0;
tmp += 2;
if (((ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_KEY_XCH) ||
(ses->ntlmssp->server_flags & NTLMSSP_NEGOTIATE_EXTENDED_SEC))
&& !calc_seckey(ses)) {
memcpy(tmp, ses->ntlmssp->ciphertext, CIFS_CPHTXT_SIZE);
sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->SessionKey.Length = cpu_to_le16(CIFS_CPHTXT_SIZE);
sec_blob->SessionKey.MaximumLength =
cpu_to_le16(CIFS_CPHTXT_SIZE);
tmp += CIFS_CPHTXT_SIZE;
} else {
sec_blob->SessionKey.BufferOffset = cpu_to_le32(tmp - *pbuffer);
sec_blob->SessionKey.Length = 0;
sec_blob->SessionKey.MaximumLength = 0;
}
*buflen = tmp - *pbuffer;
setup_ntlmv2_ret:
return rc;
}
enum securityEnum
cifs_select_sectype(struct TCP_Server_Info *server, enum securityEnum requested)
{
switch (server->negflavor) {
case CIFS_NEGFLAVOR_EXTENDED:
switch (requested) {
case Kerberos:
case RawNTLMSSP:
return requested;
case Unspecified:
if (server->sec_ntlmssp &&
(global_secflags & CIFSSEC_MAY_NTLMSSP))
return RawNTLMSSP;
if ((server->sec_kerberos || server->sec_mskerberos) &&
(global_secflags & CIFSSEC_MAY_KRB5))
return Kerberos;
fallthrough;
default:
return Unspecified;
}
case CIFS_NEGFLAVOR_UNENCAP:
switch (requested) {
case NTLM:
case NTLMv2:
return requested;
case Unspecified:
if (global_secflags & CIFSSEC_MAY_NTLMV2)
return NTLMv2;
if (global_secflags & CIFSSEC_MAY_NTLM)
return NTLM;
break;
default:
break;
}
fallthrough; /* to attempt LANMAN authentication next */
case CIFS_NEGFLAVOR_LANMAN:
switch (requested) {
case LANMAN:
return requested;
case Unspecified:
if (global_secflags & CIFSSEC_MAY_LANMAN)
return LANMAN;
fallthrough;
default:
return Unspecified;
}
default:
return Unspecified;
}
}
struct sess_data {
unsigned int xid;
struct cifs_ses *ses;
struct nls_table *nls_cp;
void (*func)(struct sess_data *);
int result;
/* we will send the SMB in three pieces:
* a fixed length beginning part, an optional
* SPNEGO blob (which can be zero length), and a
* last part which will include the strings
* and rest of bcc area. This allows us to avoid
* a large buffer 17K allocation
*/
int buf0_type;
struct kvec iov[3];
};
static int
sess_alloc_buffer(struct sess_data *sess_data, int wct)
{
int rc;
struct cifs_ses *ses = sess_data->ses;
struct smb_hdr *smb_buf;
rc = small_smb_init_no_tc(SMB_COM_SESSION_SETUP_ANDX, wct, ses,
(void **)&smb_buf);
if (rc)
return rc;
sess_data->iov[0].iov_base = (char *)smb_buf;
sess_data->iov[0].iov_len = be32_to_cpu(smb_buf->smb_buf_length) + 4;
/*
* This variable will be used to clear the buffer
* allocated above in case of any error in the calling function.
*/
sess_data->buf0_type = CIFS_SMALL_BUFFER;
/* 2000 big enough to fit max user, domain, NOS name etc. */
sess_data->iov[2].iov_base = kmalloc(2000, GFP_KERNEL);
if (!sess_data->iov[2].iov_base) {
rc = -ENOMEM;
goto out_free_smb_buf;
}
return 0;
out_free_smb_buf:
kfree(smb_buf);
sess_data->iov[0].iov_base = NULL;
sess_data->iov[0].iov_len = 0;
sess_data->buf0_type = CIFS_NO_BUFFER;
return rc;
}
static void
sess_free_buffer(struct sess_data *sess_data)
{
free_rsp_buf(sess_data->buf0_type, sess_data->iov[0].iov_base);
sess_data->buf0_type = CIFS_NO_BUFFER;
kfree(sess_data->iov[2].iov_base);
}
static int
sess_establish_session(struct sess_data *sess_data)
{
struct cifs_ses *ses = sess_data->ses;
mutex_lock(&ses->server->srv_mutex);
if (!ses->server->session_estab) {
if (ses->server->sign) {
ses->server->session_key.response =
kmemdup(ses->auth_key.response,
ses->auth_key.len, GFP_KERNEL);
if (!ses->server->session_key.response) {
mutex_unlock(&ses->server->srv_mutex);
return -ENOMEM;
}
ses->server->session_key.len =
ses->auth_key.len;
}
ses->server->sequence_number = 0x2;
ses->server->session_estab = true;
}
mutex_unlock(&ses->server->srv_mutex);
cifs_dbg(FYI, "CIFS session established successfully\n");
spin_lock(&GlobalMid_Lock);
ses->status = CifsGood;
ses->need_reconnect = false;
spin_unlock(&GlobalMid_Lock);
return 0;
}
static int
sess_sendreceive(struct sess_data *sess_data)
{
int rc;
struct smb_hdr *smb_buf = (struct smb_hdr *) sess_data->iov[0].iov_base;
__u16 count;
struct kvec rsp_iov = { NULL, 0 };
count = sess_data->iov[1].iov_len + sess_data->iov[2].iov_len;
be32_add_cpu(&smb_buf->smb_buf_length, count);
put_bcc(count, smb_buf);
rc = SendReceive2(sess_data->xid, sess_data->ses,
sess_data->iov, 3 /* num_iovecs */,
&sess_data->buf0_type,
CIFS_LOG_ERROR, &rsp_iov);
cifs_small_buf_release(sess_data->iov[0].iov_base);
memcpy(&sess_data->iov[0], &rsp_iov, sizeof(struct kvec));
return rc;
}
/*
* LANMAN and plaintext are less secure and off by default.
* So we make this explicitly be turned on in kconfig (in the
* build) and turned on at runtime (changed from the default)
* in proc/fs/cifs or via mount parm. Unfortunately this is
* needed for old Win (e.g. Win95), some obscure NAS and OS/2
*/
#ifdef CONFIG_CIFS_WEAK_PW_HASH
static void
sess_auth_lanman(struct sess_data *sess_data)
{
int rc = 0;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
char *bcc_ptr;
struct cifs_ses *ses = sess_data->ses;
char lnm_session_key[CIFS_AUTH_RESP_SIZE];
__u16 bytes_remaining;
/* lanman 2 style sessionsetup */
/* wct = 10 */
rc = sess_alloc_buffer(sess_data, 10);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
bcc_ptr = sess_data->iov[2].iov_base;
(void)cifs_ssetup_hdr(ses, pSMB);
pSMB->req.hdr.Flags2 &= ~SMBFLG2_UNICODE;
if (ses->user_name != NULL) {
/* no capabilities flags in old lanman negotiation */
pSMB->old_req.PasswordLength = cpu_to_le16(CIFS_AUTH_RESP_SIZE);
/* Calculate hash with password and copy into bcc_ptr.
* Encryption Key (stored as in cryptkey) gets used if the
* security mode bit in Negotiate Protocol response states
* to use challenge/response method (i.e. Password bit is 1).
*/
rc = calc_lanman_hash(ses->password, ses->server->cryptkey,
ses->server->sec_mode & SECMODE_PW_ENCRYPT ?
true : false, lnm_session_key);
if (rc)
goto out;
memcpy(bcc_ptr, (char *)lnm_session_key, CIFS_AUTH_RESP_SIZE);
bcc_ptr += CIFS_AUTH_RESP_SIZE;
} else {
pSMB->old_req.PasswordLength = 0;
}
/*
* can not sign if LANMAN negotiated so no need
* to calculate signing key? but what if server
* changed to do higher than lanman dialect and
* we reconnected would we ever calc signing_key?
*/
cifs_dbg(FYI, "Negotiating LANMAN setting up strings\n");
/* Unicode not allowed for LANMAN dialects */
ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
sess_data->iov[2].iov_len = (long) bcc_ptr -
(long) sess_data->iov[2].iov_base;
rc = sess_sendreceive(sess_data);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
/* lanman response has a word count of 3 */
if (smb_buf->WordCount != 3) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out;
}
if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
/* BB check if Unicode and decode strings */
if (bytes_remaining == 0) {
/* no string area to decode, do nothing */
} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
/* unicode string area must be word-aligned */
if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
++bcc_ptr;
--bytes_remaining;
}
decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
} else {
decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
}
rc = sess_establish_session(sess_data);
out:
sess_data->result = rc;
sess_data->func = NULL;
sess_free_buffer(sess_data);
}
#endif
static void
sess_auth_ntlm(struct sess_data *sess_data)
{
int rc = 0;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
char *bcc_ptr;
struct cifs_ses *ses = sess_data->ses;
__u32 capabilities;
__u16 bytes_remaining;
/* old style NTLM sessionsetup */
/* wct = 13 */
rc = sess_alloc_buffer(sess_data, 13);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
bcc_ptr = sess_data->iov[2].iov_base;
capabilities = cifs_ssetup_hdr(ses, pSMB);
pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
if (ses->user_name != NULL) {
pSMB->req_no_secext.CaseInsensitivePasswordLength =
cpu_to_le16(CIFS_AUTH_RESP_SIZE);
pSMB->req_no_secext.CaseSensitivePasswordLength =
cpu_to_le16(CIFS_AUTH_RESP_SIZE);
/* calculate ntlm response and session key */
rc = setup_ntlm_response(ses, sess_data->nls_cp);
if (rc) {
cifs_dbg(VFS, "Error %d during NTLM authentication\n",
rc);
goto out;
}
/* copy ntlm response */
memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
CIFS_AUTH_RESP_SIZE);
bcc_ptr += CIFS_AUTH_RESP_SIZE;
memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
CIFS_AUTH_RESP_SIZE);
bcc_ptr += CIFS_AUTH_RESP_SIZE;
} else {
pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
}
if (ses->capabilities & CAP_UNICODE) {
/* unicode strings must be word aligned */
if (sess_data->iov[0].iov_len % 2) {
*bcc_ptr = 0;
bcc_ptr++;
}
unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
} else {
ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
}
sess_data->iov[2].iov_len = (long) bcc_ptr -
(long) sess_data->iov[2].iov_base;
rc = sess_sendreceive(sess_data);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
if (smb_buf->WordCount != 3) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out;
}
if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
/* BB check if Unicode and decode strings */
if (bytes_remaining == 0) {
/* no string area to decode, do nothing */
} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
/* unicode string area must be word-aligned */
if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
++bcc_ptr;
--bytes_remaining;
}
decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
} else {
decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
}
rc = sess_establish_session(sess_data);
out:
sess_data->result = rc;
sess_data->func = NULL;
sess_free_buffer(sess_data);
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
}
static void
sess_auth_ntlmv2(struct sess_data *sess_data)
{
int rc = 0;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
char *bcc_ptr;
struct cifs_ses *ses = sess_data->ses;
__u32 capabilities;
__u16 bytes_remaining;
/* old style NTLM sessionsetup */
/* wct = 13 */
rc = sess_alloc_buffer(sess_data, 13);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
bcc_ptr = sess_data->iov[2].iov_base;
capabilities = cifs_ssetup_hdr(ses, pSMB);
pSMB->req_no_secext.Capabilities = cpu_to_le32(capabilities);
/* LM2 password would be here if we supported it */
pSMB->req_no_secext.CaseInsensitivePasswordLength = 0;
if (ses->user_name != NULL) {
/* calculate nlmv2 response and session key */
rc = setup_ntlmv2_rsp(ses, sess_data->nls_cp);
if (rc) {
cifs_dbg(VFS, "Error %d during NTLMv2 authentication\n", rc);
goto out;
}
memcpy(bcc_ptr, ses->auth_key.response + CIFS_SESS_KEY_SIZE,
ses->auth_key.len - CIFS_SESS_KEY_SIZE);
bcc_ptr += ses->auth_key.len - CIFS_SESS_KEY_SIZE;
/* set case sensitive password length after tilen may get
* assigned, tilen is 0 otherwise.
*/
pSMB->req_no_secext.CaseSensitivePasswordLength =
cpu_to_le16(ses->auth_key.len - CIFS_SESS_KEY_SIZE);
} else {
pSMB->req_no_secext.CaseSensitivePasswordLength = 0;
}
if (ses->capabilities & CAP_UNICODE) {
if (sess_data->iov[0].iov_len % 2) {
*bcc_ptr = 0;
bcc_ptr++;
}
unicode_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
} else {
ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
}
sess_data->iov[2].iov_len = (long) bcc_ptr -
(long) sess_data->iov[2].iov_base;
rc = sess_sendreceive(sess_data);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
if (smb_buf->WordCount != 3) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out;
}
if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
/* BB check if Unicode and decode strings */
if (bytes_remaining == 0) {
/* no string area to decode, do nothing */
} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
/* unicode string area must be word-aligned */
if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
++bcc_ptr;
--bytes_remaining;
}
decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
} else {
decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
}
rc = sess_establish_session(sess_data);
out:
sess_data->result = rc;
sess_data->func = NULL;
sess_free_buffer(sess_data);
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
}
#ifdef CONFIG_CIFS_UPCALL
static void
sess_auth_kerberos(struct sess_data *sess_data)
{
int rc = 0;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
char *bcc_ptr;
struct cifs_ses *ses = sess_data->ses;
__u32 capabilities;
__u16 bytes_remaining;
struct key *spnego_key = NULL;
struct cifs_spnego_msg *msg;
u16 blob_len;
/* extended security */
/* wct = 12 */
rc = sess_alloc_buffer(sess_data, 12);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
bcc_ptr = sess_data->iov[2].iov_base;
capabilities = cifs_ssetup_hdr(ses, pSMB);
spnego_key = cifs_get_spnego_key(ses);
if (IS_ERR(spnego_key)) {
rc = PTR_ERR(spnego_key);
spnego_key = NULL;
goto out;
}
msg = spnego_key->payload.data[0];
/*
* check version field to make sure that cifs.upcall is
* sending us a response in an expected form
*/
if (msg->version != CIFS_SPNEGO_UPCALL_VERSION) {
cifs_dbg(VFS, "incorrect version of cifs.upcall (expected %d but got %d)\n",
CIFS_SPNEGO_UPCALL_VERSION, msg->version);
rc = -EKEYREJECTED;
goto out_put_spnego_key;
}
ses->auth_key.response = kmemdup(msg->data, msg->sesskey_len,
GFP_KERNEL);
if (!ses->auth_key.response) {
cifs_dbg(VFS, "Kerberos can't allocate (%u bytes) memory\n",
msg->sesskey_len);
rc = -ENOMEM;
goto out_put_spnego_key;
}
ses->auth_key.len = msg->sesskey_len;
pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
capabilities |= CAP_EXTENDED_SECURITY;
pSMB->req.Capabilities = cpu_to_le32(capabilities);
sess_data->iov[1].iov_base = msg->data + msg->sesskey_len;
sess_data->iov[1].iov_len = msg->secblob_len;
pSMB->req.SecurityBlobLength = cpu_to_le16(sess_data->iov[1].iov_len);
if (ses->capabilities & CAP_UNICODE) {
/* unicode strings must be word aligned */
if ((sess_data->iov[0].iov_len
+ sess_data->iov[1].iov_len) % 2) {
*bcc_ptr = 0;
bcc_ptr++;
}
unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
unicode_domain_string(&bcc_ptr, ses, sess_data->nls_cp);
} else {
/* BB: is this right? */
ascii_ssetup_strings(&bcc_ptr, ses, sess_data->nls_cp);
}
sess_data->iov[2].iov_len = (long) bcc_ptr -
(long) sess_data->iov[2].iov_base;
rc = sess_sendreceive(sess_data);
if (rc)
goto out_put_spnego_key;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
if (smb_buf->WordCount != 4) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out_put_spnego_key;
}
if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
if (blob_len > bytes_remaining) {
cifs_dbg(VFS, "bad security blob length %d\n",
blob_len);
rc = -EINVAL;
goto out_put_spnego_key;
}
bcc_ptr += blob_len;
bytes_remaining -= blob_len;
/* BB check if Unicode and decode strings */
if (bytes_remaining == 0) {
/* no string area to decode, do nothing */
} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
/* unicode string area must be word-aligned */
if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
++bcc_ptr;
--bytes_remaining;
}
decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
} else {
decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
}
rc = sess_establish_session(sess_data);
out_put_spnego_key:
key_invalidate(spnego_key);
key_put(spnego_key);
out:
sess_data->result = rc;
sess_data->func = NULL;
sess_free_buffer(sess_data);
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
}
#endif /* ! CONFIG_CIFS_UPCALL */
/*
* The required kvec buffers have to be allocated before calling this
* function.
*/
static int
_sess_auth_rawntlmssp_assemble_req(struct sess_data *sess_data)
{
SESSION_SETUP_ANDX *pSMB;
struct cifs_ses *ses = sess_data->ses;
__u32 capabilities;
char *bcc_ptr;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
capabilities = cifs_ssetup_hdr(ses, pSMB);
if ((pSMB->req.hdr.Flags2 & SMBFLG2_UNICODE) == 0) {
cifs_dbg(VFS, "NTLMSSP requires Unicode support\n");
return -ENOSYS;
}
pSMB->req.hdr.Flags2 |= SMBFLG2_EXT_SEC;
capabilities |= CAP_EXTENDED_SECURITY;
pSMB->req.Capabilities |= cpu_to_le32(capabilities);
bcc_ptr = sess_data->iov[2].iov_base;
/* unicode strings must be word aligned */
if ((sess_data->iov[0].iov_len + sess_data->iov[1].iov_len) % 2) {
*bcc_ptr = 0;
bcc_ptr++;
}
unicode_oslm_strings(&bcc_ptr, sess_data->nls_cp);
sess_data->iov[2].iov_len = (long) bcc_ptr -
(long) sess_data->iov[2].iov_base;
return 0;
}
static void
sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data);
static void
sess_auth_rawntlmssp_negotiate(struct sess_data *sess_data)
{
int rc;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
struct cifs_ses *ses = sess_data->ses;
__u16 bytes_remaining;
char *bcc_ptr;
u16 blob_len;
cifs_dbg(FYI, "rawntlmssp session setup negotiate phase\n");
/*
* if memory allocation is successful, caller of this function
* frees it.
*/
ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
if (!ses->ntlmssp) {
rc = -ENOMEM;
goto out;
}
ses->ntlmssp->sesskey_per_smbsess = false;
/* wct = 12 */
rc = sess_alloc_buffer(sess_data, 12);
if (rc)
goto out;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
/* Build security blob before we assemble the request */
build_ntlmssp_negotiate_blob(pSMB->req.SecurityBlob, ses);
sess_data->iov[1].iov_len = sizeof(NEGOTIATE_MESSAGE);
sess_data->iov[1].iov_base = pSMB->req.SecurityBlob;
pSMB->req.SecurityBlobLength = cpu_to_le16(sizeof(NEGOTIATE_MESSAGE));
rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
if (rc)
goto out;
rc = sess_sendreceive(sess_data);
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
/* If true, rc here is expected and not an error */
if (sess_data->buf0_type != CIFS_NO_BUFFER &&
smb_buf->Status.CifsError ==
cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))
rc = 0;
if (rc)
goto out;
cifs_dbg(FYI, "rawntlmssp session setup challenge phase\n");
if (smb_buf->WordCount != 4) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out;
}
ses->Suid = smb_buf->Uid; /* UID left in wire format (le) */
cifs_dbg(FYI, "UID = %llu\n", ses->Suid);
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
if (blob_len > bytes_remaining) {
cifs_dbg(VFS, "bad security blob length %d\n",
blob_len);
rc = -EINVAL;
goto out;
}
rc = decode_ntlmssp_challenge(bcc_ptr, blob_len, ses);
out:
sess_free_buffer(sess_data);
if (!rc) {
sess_data->func = sess_auth_rawntlmssp_authenticate;
return;
}
/* Else error. Cleanup */
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
kfree(ses->ntlmssp);
ses->ntlmssp = NULL;
sess_data->func = NULL;
sess_data->result = rc;
}
static void
sess_auth_rawntlmssp_authenticate(struct sess_data *sess_data)
{
int rc;
struct smb_hdr *smb_buf;
SESSION_SETUP_ANDX *pSMB;
struct cifs_ses *ses = sess_data->ses;
__u16 bytes_remaining;
char *bcc_ptr;
unsigned char *ntlmsspblob = NULL;
u16 blob_len;
cifs_dbg(FYI, "rawntlmssp session setup authenticate phase\n");
/* wct = 12 */
rc = sess_alloc_buffer(sess_data, 12);
if (rc)
goto out;
/* Build security blob before we assemble the request */
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)pSMB;
rc = build_ntlmssp_auth_blob(&ntlmsspblob,
&blob_len, ses, sess_data->nls_cp);
if (rc)
goto out_free_ntlmsspblob;
sess_data->iov[1].iov_len = blob_len;
sess_data->iov[1].iov_base = ntlmsspblob;
pSMB->req.SecurityBlobLength = cpu_to_le16(blob_len);
/*
* Make sure that we tell the server that we are using
* the uid that it just gave us back on the response
* (challenge)
*/
smb_buf->Uid = ses->Suid;
rc = _sess_auth_rawntlmssp_assemble_req(sess_data);
if (rc)
goto out_free_ntlmsspblob;
rc = sess_sendreceive(sess_data);
if (rc)
goto out_free_ntlmsspblob;
pSMB = (SESSION_SETUP_ANDX *)sess_data->iov[0].iov_base;
smb_buf = (struct smb_hdr *)sess_data->iov[0].iov_base;
if (smb_buf->WordCount != 4) {
rc = -EIO;
cifs_dbg(VFS, "bad word count %d\n", smb_buf->WordCount);
goto out_free_ntlmsspblob;
}
if (le16_to_cpu(pSMB->resp.Action) & GUEST_LOGIN)
cifs_dbg(FYI, "Guest login\n"); /* BB mark SesInfo struct? */
if (ses->Suid != smb_buf->Uid) {
ses->Suid = smb_buf->Uid;
cifs_dbg(FYI, "UID changed! new UID = %llu\n", ses->Suid);
}
bytes_remaining = get_bcc(smb_buf);
bcc_ptr = pByteArea(smb_buf);
blob_len = le16_to_cpu(pSMB->resp.SecurityBlobLength);
if (blob_len > bytes_remaining) {
cifs_dbg(VFS, "bad security blob length %d\n",
blob_len);
rc = -EINVAL;
goto out_free_ntlmsspblob;
}
bcc_ptr += blob_len;
bytes_remaining -= blob_len;
/* BB check if Unicode and decode strings */
if (bytes_remaining == 0) {
/* no string area to decode, do nothing */
} else if (smb_buf->Flags2 & SMBFLG2_UNICODE) {
/* unicode string area must be word-aligned */
if (((unsigned long) bcc_ptr - (unsigned long) smb_buf) % 2) {
++bcc_ptr;
--bytes_remaining;
}
decode_unicode_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
} else {
decode_ascii_ssetup(&bcc_ptr, bytes_remaining, ses,
sess_data->nls_cp);
}
out_free_ntlmsspblob:
kfree(ntlmsspblob);
out:
sess_free_buffer(sess_data);
if (!rc)
rc = sess_establish_session(sess_data);
/* Cleanup */
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
kfree(ses->ntlmssp);
ses->ntlmssp = NULL;
sess_data->func = NULL;
sess_data->result = rc;
}
static int select_sec(struct cifs_ses *ses, struct sess_data *sess_data)
{
int type;
type = cifs_select_sectype(ses->server, ses->sectype);
cifs_dbg(FYI, "sess setup type %d\n", type);
if (type == Unspecified) {
cifs_dbg(VFS, "Unable to select appropriate authentication method!\n");
return -EINVAL;
}
switch (type) {
case LANMAN:
/* LANMAN and plaintext are less secure and off by default.
* So we make this explicitly be turned on in kconfig (in the
* build) and turned on at runtime (changed from the default)
* in proc/fs/cifs or via mount parm. Unfortunately this is
* needed for old Win (e.g. Win95), some obscure NAS and OS/2 */
#ifdef CONFIG_CIFS_WEAK_PW_HASH
sess_data->func = sess_auth_lanman;
break;
#else
return -EOPNOTSUPP;
#endif
case NTLM:
sess_data->func = sess_auth_ntlm;
break;
case NTLMv2:
sess_data->func = sess_auth_ntlmv2;
break;
case Kerberos:
#ifdef CONFIG_CIFS_UPCALL
sess_data->func = sess_auth_kerberos;
break;
#else
cifs_dbg(VFS, "Kerberos negotiated but upcall support disabled!\n");
return -ENOSYS;
#endif /* CONFIG_CIFS_UPCALL */
case RawNTLMSSP:
sess_data->func = sess_auth_rawntlmssp_negotiate;
break;
default:
cifs_dbg(VFS, "secType %d not supported!\n", type);
return -ENOSYS;
}
return 0;
}
int CIFS_SessSetup(const unsigned int xid, struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
int rc = 0;
struct sess_data *sess_data;
if (ses == NULL) {
WARN(1, "%s: ses == NULL!", __func__);
return -EINVAL;
}
sess_data = kzalloc(sizeof(struct sess_data), GFP_KERNEL);
if (!sess_data)
return -ENOMEM;
rc = select_sec(ses, sess_data);
if (rc)
goto out;
sess_data->xid = xid;
sess_data->ses = ses;
sess_data->buf0_type = CIFS_NO_BUFFER;
sess_data->nls_cp = (struct nls_table *) nls_cp;
while (sess_data->func)
sess_data->func(sess_data);
/* Store result before we free sess_data */
rc = sess_data->result;
out:
kfree(sess_data);
return rc;
}