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smb2pdu.c
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smb2pdu.c
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/*
* fs/cifs/smb2pdu.c
*
* Copyright (C) International Business Machines Corp., 2009, 2013
* Etersoft, 2012
* Author(s): Steve French (sfrench@us.ibm.com)
* Pavel Shilovsky (pshilovsky@samba.org) 2012
*
* Contains the routines for constructing the SMB2 PDUs themselves
*
* 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
*/
/* SMB2 PDU handling routines here - except for leftovers (eg session setup) */
/* Note that there are handle based routines which must be */
/* treated slightly differently for reconnection purposes since we never */
/* want to reuse a stale file handle and only the caller knows the file info */
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/vfs.h>
#include <linux/task_io_accounting_ops.h>
#include <linux/uaccess.h>
#include <linux/pagemap.h>
#include <linux/xattr.h>
#include "smb2pdu.h"
#include "cifsglob.h"
#include "cifsacl.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "ntlmssp.h"
#include "smb2status.h"
#include "smb2glob.h"
#include "cifspdu.h"
#include "cifs_spnego.h"
/*
* The following table defines the expected "StructureSize" of SMB2 requests
* in order by SMB2 command. This is similar to "wct" in SMB/CIFS requests.
*
* Note that commands are defined in smb2pdu.h in le16 but the array below is
* indexed by command in host byte order.
*/
static const int smb2_req_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
/* SMB2_NEGOTIATE */ 36,
/* SMB2_SESSION_SETUP */ 25,
/* SMB2_LOGOFF */ 4,
/* SMB2_TREE_CONNECT */ 9,
/* SMB2_TREE_DISCONNECT */ 4,
/* SMB2_CREATE */ 57,
/* SMB2_CLOSE */ 24,
/* SMB2_FLUSH */ 24,
/* SMB2_READ */ 49,
/* SMB2_WRITE */ 49,
/* SMB2_LOCK */ 48,
/* SMB2_IOCTL */ 57,
/* SMB2_CANCEL */ 4,
/* SMB2_ECHO */ 4,
/* SMB2_QUERY_DIRECTORY */ 33,
/* SMB2_CHANGE_NOTIFY */ 32,
/* SMB2_QUERY_INFO */ 41,
/* SMB2_SET_INFO */ 33,
/* SMB2_OPLOCK_BREAK */ 24 /* BB this is 36 for LEASE_BREAK variant */
};
static void
smb2_hdr_assemble(struct smb2_hdr *hdr, __le16 smb2_cmd /* command */ ,
const struct cifs_tcon *tcon)
{
struct smb2_pdu *pdu = (struct smb2_pdu *)hdr;
char *temp = (char *)hdr;
/* lookup word count ie StructureSize from table */
__u16 parmsize = smb2_req_struct_sizes[le16_to_cpu(smb2_cmd)];
/*
* smaller than SMALL_BUFFER_SIZE but bigger than fixed area of
* largest operations (Create)
*/
memset(temp, 0, 256);
/* Note this is only network field converted to big endian */
hdr->smb2_buf_length = cpu_to_be32(parmsize + sizeof(struct smb2_hdr)
- 4 /* RFC 1001 length field itself not counted */);
hdr->ProtocolId[0] = 0xFE;
hdr->ProtocolId[1] = 'S';
hdr->ProtocolId[2] = 'M';
hdr->ProtocolId[3] = 'B';
hdr->StructureSize = cpu_to_le16(64);
hdr->Command = smb2_cmd;
hdr->CreditRequest = cpu_to_le16(2); /* BB make this dynamic */
hdr->ProcessId = cpu_to_le32((__u16)current->tgid);
if (!tcon)
goto out;
/* GLOBAL_CAP_LARGE_MTU will only be set if dialect > SMB2.02 */
/* See sections 2.2.4 and 3.2.4.1.5 of MS-SMB2 */
if ((tcon->ses) && (tcon->ses->server) &&
(tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LARGE_MTU))
hdr->CreditCharge = cpu_to_le16(1);
/* else CreditCharge MBZ */
hdr->TreeId = tcon->tid;
/* Uid is not converted */
if (tcon->ses)
hdr->SessionId = tcon->ses->Suid;
/*
* If we would set SMB2_FLAGS_DFS_OPERATIONS on open we also would have
* to pass the path on the Open SMB prefixed by \\server\share.
* Not sure when we would need to do the augmented path (if ever) and
* setting this flag breaks the SMB2 open operation since it is
* illegal to send an empty path name (without \\server\share prefix)
* when the DFS flag is set in the SMB open header. We could
* consider setting the flag on all operations other than open
* but it is safer to net set it for now.
*/
/* if (tcon->share_flags & SHI1005_FLAGS_DFS)
hdr->Flags |= SMB2_FLAGS_DFS_OPERATIONS; */
if (tcon->ses && tcon->ses->server && tcon->ses->server->sign)
hdr->Flags |= SMB2_FLAGS_SIGNED;
out:
pdu->StructureSize2 = cpu_to_le16(parmsize);
return;
}
static int
smb2_reconnect(__le16 smb2_command, struct cifs_tcon *tcon)
{
int rc = 0;
struct nls_table *nls_codepage;
struct cifs_ses *ses;
struct TCP_Server_Info *server;
/*
* SMB2s NegProt, SessSetup, Logoff do not have tcon yet so
* check for tcp and smb session status done differently
* for those three - in the calling routine.
*/
if (tcon == NULL)
return rc;
if (smb2_command == SMB2_TREE_CONNECT)
return rc;
if (tcon->tidStatus == CifsExiting) {
/*
* only tree disconnect, open, and write,
* (and ulogoff which does not have tcon)
* are allowed as we start force umount.
*/
if ((smb2_command != SMB2_WRITE) &&
(smb2_command != SMB2_CREATE) &&
(smb2_command != SMB2_TREE_DISCONNECT)) {
cifs_dbg(FYI, "can not send cmd %d while umounting\n",
smb2_command);
return -ENODEV;
}
}
if ((!tcon->ses) || (tcon->ses->status == CifsExiting) ||
(!tcon->ses->server))
return -EIO;
ses = tcon->ses;
server = ses->server;
/*
* Give demultiplex thread up to 10 seconds to reconnect, should be
* greater than cifs socket timeout which is 7 seconds
*/
while (server->tcpStatus == CifsNeedReconnect) {
/*
* Return to caller for TREE_DISCONNECT and LOGOFF and CLOSE
* here since they are implicitly done when session drops.
*/
switch (smb2_command) {
/*
* BB Should we keep oplock break and add flush to exceptions?
*/
case SMB2_TREE_DISCONNECT:
case SMB2_CANCEL:
case SMB2_CLOSE:
case SMB2_OPLOCK_BREAK:
return -EAGAIN;
}
wait_event_interruptible_timeout(server->response_q,
(server->tcpStatus != CifsNeedReconnect), 10 * HZ);
/* are we still trying to reconnect? */
if (server->tcpStatus != CifsNeedReconnect)
break;
/*
* on "soft" mounts we wait once. Hard mounts keep
* retrying until process is killed or server comes
* back on-line
*/
if (!tcon->retry) {
cifs_dbg(FYI, "gave up waiting on reconnect in smb_init\n");
return -EHOSTDOWN;
}
}
if (!tcon->ses->need_reconnect && !tcon->need_reconnect)
return rc;
nls_codepage = load_nls_default();
/*
* need to prevent multiple threads trying to simultaneously reconnect
* the same SMB session
*/
mutex_lock(&tcon->ses->session_mutex);
rc = cifs_negotiate_protocol(0, tcon->ses);
if (!rc && tcon->ses->need_reconnect)
rc = cifs_setup_session(0, tcon->ses, nls_codepage);
if (rc || !tcon->need_reconnect) {
mutex_unlock(&tcon->ses->session_mutex);
goto out;
}
cifs_mark_open_files_invalid(tcon);
rc = SMB2_tcon(0, tcon->ses, tcon->treeName, tcon, nls_codepage);
mutex_unlock(&tcon->ses->session_mutex);
cifs_dbg(FYI, "reconnect tcon rc = %d\n", rc);
if (rc)
goto out;
atomic_inc(&tconInfoReconnectCount);
out:
/*
* Check if handle based operation so we know whether we can continue
* or not without returning to caller to reset file handle.
*/
/*
* BB Is flush done by server on drop of tcp session? Should we special
* case it and skip above?
*/
switch (smb2_command) {
case SMB2_FLUSH:
case SMB2_READ:
case SMB2_WRITE:
case SMB2_LOCK:
case SMB2_IOCTL:
case SMB2_QUERY_DIRECTORY:
case SMB2_CHANGE_NOTIFY:
case SMB2_QUERY_INFO:
case SMB2_SET_INFO:
return -EAGAIN;
}
unload_nls(nls_codepage);
return rc;
}
/*
* Allocate and return pointer to an SMB request hdr, and set basic
* SMB information in the SMB header. If the return code is zero, this
* function must have filled in request_buf pointer.
*/
static int
small_smb2_init(__le16 smb2_command, struct cifs_tcon *tcon,
void **request_buf)
{
int rc = 0;
rc = smb2_reconnect(smb2_command, tcon);
if (rc)
return rc;
/* BB eventually switch this to SMB2 specific small buf size */
*request_buf = cifs_small_buf_get();
if (*request_buf == NULL) {
/* BB should we add a retry in here if not a writepage? */
return -ENOMEM;
}
smb2_hdr_assemble((struct smb2_hdr *) *request_buf, smb2_command, tcon);
if (tcon != NULL) {
#ifdef CONFIG_CIFS_STATS2
uint16_t com_code = le16_to_cpu(smb2_command);
cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_sent[com_code]);
#endif
cifs_stats_inc(&tcon->num_smbs_sent);
}
return rc;
}
#ifdef CONFIG_CIFS_SMB311
/* offset is sizeof smb2_negotiate_req - 4 but rounded up to 8 bytes */
#define OFFSET_OF_NEG_CONTEXT 0x68 /* sizeof(struct smb2_negotiate_req) - 4 */
#define SMB2_PREAUTH_INTEGRITY_CAPABILITIES cpu_to_le16(1)
#define SMB2_ENCRYPTION_CAPABILITIES cpu_to_le16(2)
static void
build_preauth_ctxt(struct smb2_preauth_neg_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_PREAUTH_INTEGRITY_CAPABILITIES;
pneg_ctxt->DataLength = cpu_to_le16(38);
pneg_ctxt->HashAlgorithmCount = cpu_to_le16(1);
pneg_ctxt->SaltLength = cpu_to_le16(SMB311_SALT_SIZE);
get_random_bytes(pneg_ctxt->Salt, SMB311_SALT_SIZE);
pneg_ctxt->HashAlgorithms = SMB2_PREAUTH_INTEGRITY_SHA512;
}
static void
build_encrypt_ctxt(struct smb2_encryption_neg_context *pneg_ctxt)
{
pneg_ctxt->ContextType = SMB2_ENCRYPTION_CAPABILITIES;
pneg_ctxt->DataLength = cpu_to_le16(6);
pneg_ctxt->CipherCount = cpu_to_le16(2);
pneg_ctxt->Ciphers[0] = SMB2_ENCRYPTION_AES128_GCM;
pneg_ctxt->Ciphers[1] = SMB2_ENCRYPTION_AES128_CCM;
}
static void
assemble_neg_contexts(struct smb2_negotiate_req *req)
{
/* +4 is to account for the RFC1001 len field */
char *pneg_ctxt = (char *)req + OFFSET_OF_NEG_CONTEXT + 4;
build_preauth_ctxt((struct smb2_preauth_neg_context *)pneg_ctxt);
/* Add 2 to size to round to 8 byte boundary */
pneg_ctxt += 2 + sizeof(struct smb2_preauth_neg_context);
build_encrypt_ctxt((struct smb2_encryption_neg_context *)pneg_ctxt);
req->NegotiateContextOffset = cpu_to_le32(OFFSET_OF_NEG_CONTEXT);
req->NegotiateContextCount = cpu_to_le16(2);
inc_rfc1001_len(req, 4 + sizeof(struct smb2_preauth_neg_context) + 2
+ sizeof(struct smb2_encryption_neg_context)); /* calculate hash */
}
#else
static void assemble_neg_contexts(struct smb2_negotiate_req *req)
{
return;
}
#endif /* SMB311 */
/*
*
* SMB2 Worker functions follow:
*
* The general structure of the worker functions is:
* 1) Call smb2_init (assembles SMB2 header)
* 2) Initialize SMB2 command specific fields in fixed length area of SMB
* 3) Call smb_sendrcv2 (sends request on socket and waits for response)
* 4) Decode SMB2 command specific fields in the fixed length area
* 5) Decode variable length data area (if any for this SMB2 command type)
* 6) Call free smb buffer
* 7) return
*
*/
int
SMB2_negotiate(const unsigned int xid, struct cifs_ses *ses)
{
struct smb2_negotiate_req *req;
struct smb2_negotiate_rsp *rsp;
struct kvec iov[1];
int rc = 0;
int resp_buftype;
struct TCP_Server_Info *server = ses->server;
int blob_offset, blob_length;
char *security_blob;
int flags = CIFS_NEG_OP;
cifs_dbg(FYI, "Negotiate protocol\n");
if (!server) {
WARN(1, "%s: server is NULL!\n", __func__);
return -EIO;
}
rc = small_smb2_init(SMB2_NEGOTIATE, NULL, (void **) &req);
if (rc)
return rc;
req->hdr.SessionId = 0;
req->Dialects[0] = cpu_to_le16(ses->server->vals->protocol_id);
req->DialectCount = cpu_to_le16(1); /* One vers= at a time for now */
inc_rfc1001_len(req, 2);
/* only one of SMB2 signing flags may be set in SMB2 request */
if (ses->sign)
req->SecurityMode = cpu_to_le16(SMB2_NEGOTIATE_SIGNING_REQUIRED);
else if (global_secflags & CIFSSEC_MAY_SIGN)
req->SecurityMode = cpu_to_le16(SMB2_NEGOTIATE_SIGNING_ENABLED);
else
req->SecurityMode = 0;
req->Capabilities = cpu_to_le32(ses->server->vals->req_capabilities);
/* ClientGUID must be zero for SMB2.02 dialect */
if (ses->server->vals->protocol_id == SMB20_PROT_ID)
memset(req->ClientGUID, 0, SMB2_CLIENT_GUID_SIZE);
else {
memcpy(req->ClientGUID, server->client_guid,
SMB2_CLIENT_GUID_SIZE);
if (ses->server->vals->protocol_id == SMB311_PROT_ID)
assemble_neg_contexts(req);
}
iov[0].iov_base = (char *)req;
/* 4 for rfc1002 length field */
iov[0].iov_len = get_rfc1002_length(req) + 4;
rc = SendReceive2(xid, ses, iov, 1, &resp_buftype, flags);
rsp = (struct smb2_negotiate_rsp *)iov[0].iov_base;
/*
* No tcon so can't do
* cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_fail[SMB2...]);
*/
if (rc != 0)
goto neg_exit;
cifs_dbg(FYI, "mode 0x%x\n", rsp->SecurityMode);
/* BB we may eventually want to match the negotiated vs. requested
dialect, even though we are only requesting one at a time */
if (rsp->DialectRevision == cpu_to_le16(SMB20_PROT_ID))
cifs_dbg(FYI, "negotiated smb2.0 dialect\n");
else if (rsp->DialectRevision == cpu_to_le16(SMB21_PROT_ID))
cifs_dbg(FYI, "negotiated smb2.1 dialect\n");
else if (rsp->DialectRevision == cpu_to_le16(SMB30_PROT_ID))
cifs_dbg(FYI, "negotiated smb3.0 dialect\n");
else if (rsp->DialectRevision == cpu_to_le16(SMB302_PROT_ID))
cifs_dbg(FYI, "negotiated smb3.02 dialect\n");
#ifdef CONFIG_CIFS_SMB311
else if (rsp->DialectRevision == cpu_to_le16(SMB311_PROT_ID))
cifs_dbg(FYI, "negotiated smb3.1.1 dialect\n");
#endif /* SMB311 */
else {
cifs_dbg(VFS, "Illegal dialect returned by server 0x%x\n",
le16_to_cpu(rsp->DialectRevision));
rc = -EIO;
goto neg_exit;
}
server->dialect = le16_to_cpu(rsp->DialectRevision);
/* SMB2 only has an extended negflavor */
server->negflavor = CIFS_NEGFLAVOR_EXTENDED;
/* set it to the maximum buffer size value we can send with 1 credit */
server->maxBuf = min_t(unsigned int, le32_to_cpu(rsp->MaxTransactSize),
SMB2_MAX_BUFFER_SIZE);
server->max_read = le32_to_cpu(rsp->MaxReadSize);
server->max_write = le32_to_cpu(rsp->MaxWriteSize);
/* BB Do we need to validate the SecurityMode? */
server->sec_mode = le16_to_cpu(rsp->SecurityMode);
server->capabilities = le32_to_cpu(rsp->Capabilities);
/* Internal types */
server->capabilities |= SMB2_NT_FIND | SMB2_LARGE_FILES;
security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
&rsp->hdr);
/*
* See MS-SMB2 section 2.2.4: if no blob, client picks default which
* for us will be
* ses->sectype = RawNTLMSSP;
* but for time being this is our only auth choice so doesn't matter.
* We just found a server which sets blob length to zero expecting raw.
*/
if (blob_length == 0)
cifs_dbg(FYI, "missing security blob on negprot\n");
rc = cifs_enable_signing(server, ses->sign);
if (rc)
goto neg_exit;
if (blob_length) {
rc = decode_negTokenInit(security_blob, blob_length, server);
if (rc == 1)
rc = 0;
else if (rc == 0)
rc = -EIO;
}
neg_exit:
free_rsp_buf(resp_buftype, rsp);
return rc;
}
int smb3_validate_negotiate(const unsigned int xid, struct cifs_tcon *tcon)
{
int rc = 0;
struct validate_negotiate_info_req vneg_inbuf;
struct validate_negotiate_info_rsp *pneg_rsp;
u32 rsplen;
cifs_dbg(FYI, "validate negotiate\n");
/*
* validation ioctl must be signed, so no point sending this if we
* can not sign it. We could eventually change this to selectively
* sign just this, the first and only signed request on a connection.
* This is good enough for now since a user who wants better security
* would also enable signing on the mount. Having validation of
* negotiate info for signed connections helps reduce attack vectors
*/
if (tcon->ses->server->sign == false)
return 0; /* validation requires signing */
vneg_inbuf.Capabilities =
cpu_to_le32(tcon->ses->server->vals->req_capabilities);
memcpy(vneg_inbuf.Guid, tcon->ses->server->client_guid,
SMB2_CLIENT_GUID_SIZE);
if (tcon->ses->sign)
vneg_inbuf.SecurityMode =
cpu_to_le16(SMB2_NEGOTIATE_SIGNING_REQUIRED);
else if (global_secflags & CIFSSEC_MAY_SIGN)
vneg_inbuf.SecurityMode =
cpu_to_le16(SMB2_NEGOTIATE_SIGNING_ENABLED);
else
vneg_inbuf.SecurityMode = 0;
vneg_inbuf.DialectCount = cpu_to_le16(1);
vneg_inbuf.Dialects[0] =
cpu_to_le16(tcon->ses->server->vals->protocol_id);
rc = SMB2_ioctl(xid, tcon, NO_FILE_ID, NO_FILE_ID,
FSCTL_VALIDATE_NEGOTIATE_INFO, true /* is_fsctl */,
(char *)&vneg_inbuf, sizeof(struct validate_negotiate_info_req),
(char **)&pneg_rsp, &rsplen);
if (rc != 0) {
cifs_dbg(VFS, "validate protocol negotiate failed: %d\n", rc);
return -EIO;
}
if (rsplen != sizeof(struct validate_negotiate_info_rsp)) {
cifs_dbg(VFS, "invalid size of protocol negotiate response\n");
return -EIO;
}
/* check validate negotiate info response matches what we got earlier */
if (pneg_rsp->Dialect !=
cpu_to_le16(tcon->ses->server->vals->protocol_id))
goto vneg_out;
if (pneg_rsp->SecurityMode != cpu_to_le16(tcon->ses->server->sec_mode))
goto vneg_out;
/* do not validate server guid because not saved at negprot time yet */
if ((le32_to_cpu(pneg_rsp->Capabilities) | SMB2_NT_FIND |
SMB2_LARGE_FILES) != tcon->ses->server->capabilities)
goto vneg_out;
/* validate negotiate successful */
cifs_dbg(FYI, "validate negotiate info successful\n");
return 0;
vneg_out:
cifs_dbg(VFS, "protocol revalidation - security settings mismatch\n");
return -EIO;
}
int
SMB2_sess_setup(const unsigned int xid, struct cifs_ses *ses,
const struct nls_table *nls_cp)
{
struct smb2_sess_setup_req *req;
struct smb2_sess_setup_rsp *rsp = NULL;
struct kvec iov[2];
int rc = 0;
int resp_buftype = CIFS_NO_BUFFER;
__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
struct TCP_Server_Info *server = ses->server;
u16 blob_length = 0;
struct key *spnego_key = NULL;
char *security_blob = NULL;
char *ntlmssp_blob = NULL;
bool use_spnego = false; /* else use raw ntlmssp */
cifs_dbg(FYI, "Session Setup\n");
if (!server) {
WARN(1, "%s: server is NULL!\n", __func__);
return -EIO;
}
/*
* If we are here due to reconnect, free per-smb session key
* in case signing was required.
*/
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
/*
* If memory allocation is successful, caller of this function
* frees it.
*/
ses->ntlmssp = kmalloc(sizeof(struct ntlmssp_auth), GFP_KERNEL);
if (!ses->ntlmssp)
return -ENOMEM;
ses->ntlmssp->sesskey_per_smbsess = true;
/* FIXME: allow for other auth types besides NTLMSSP (e.g. krb5) */
if (ses->sectype != Kerberos && ses->sectype != RawNTLMSSP)
ses->sectype = RawNTLMSSP;
ssetup_ntlmssp_authenticate:
if (phase == NtLmChallenge)
phase = NtLmAuthenticate; /* if ntlmssp, now final phase */
rc = small_smb2_init(SMB2_SESSION_SETUP, NULL, (void **) &req);
if (rc)
return rc;
req->hdr.SessionId = 0; /* First session, not a reauthenticate */
req->Flags = 0; /* MBZ */
/* to enable echos and oplocks */
req->hdr.CreditRequest = cpu_to_le16(3);
/* only one of SMB2 signing flags may be set in SMB2 request */
if (server->sign)
req->SecurityMode = SMB2_NEGOTIATE_SIGNING_REQUIRED;
else if (global_secflags & CIFSSEC_MAY_SIGN) /* one flag unlike MUST_ */
req->SecurityMode = SMB2_NEGOTIATE_SIGNING_ENABLED;
else
req->SecurityMode = 0;
req->Capabilities = 0;
req->Channel = 0; /* MBZ */
iov[0].iov_base = (char *)req;
/* 4 for rfc1002 length field and 1 for pad */
iov[0].iov_len = get_rfc1002_length(req) + 4 - 1;
if (ses->sectype == Kerberos) {
#ifdef CONFIG_CIFS_UPCALL
struct cifs_spnego_msg *msg;
spnego_key = cifs_get_spnego_key(ses);
if (IS_ERR(spnego_key)) {
rc = PTR_ERR(spnego_key);
spnego_key = NULL;
goto ssetup_exit;
}
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,
"bad cifs.upcall version. Expected %d got %d",
CIFS_SPNEGO_UPCALL_VERSION, msg->version);
rc = -EKEYREJECTED;
goto ssetup_exit;
}
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",
msg->sesskey_len);
rc = -ENOMEM;
goto ssetup_exit;
}
ses->auth_key.len = msg->sesskey_len;
blob_length = msg->secblob_len;
iov[1].iov_base = msg->data + msg->sesskey_len;
iov[1].iov_len = blob_length;
#else
rc = -EOPNOTSUPP;
goto ssetup_exit;
#endif /* CONFIG_CIFS_UPCALL */
} else if (phase == NtLmNegotiate) { /* if not krb5 must be ntlmssp */
ntlmssp_blob = kmalloc(sizeof(struct _NEGOTIATE_MESSAGE),
GFP_KERNEL);
if (ntlmssp_blob == NULL) {
rc = -ENOMEM;
goto ssetup_exit;
}
build_ntlmssp_negotiate_blob(ntlmssp_blob, ses);
if (use_spnego) {
/* blob_length = build_spnego_ntlmssp_blob(
&security_blob,
sizeof(struct _NEGOTIATE_MESSAGE),
ntlmssp_blob); */
/* BB eventually need to add this */
cifs_dbg(VFS, "spnego not supported for SMB2 yet\n");
rc = -EOPNOTSUPP;
kfree(ntlmssp_blob);
goto ssetup_exit;
} else {
blob_length = sizeof(struct _NEGOTIATE_MESSAGE);
/* with raw NTLMSSP we don't encapsulate in SPNEGO */
security_blob = ntlmssp_blob;
}
iov[1].iov_base = security_blob;
iov[1].iov_len = blob_length;
} else if (phase == NtLmAuthenticate) {
req->hdr.SessionId = ses->Suid;
ntlmssp_blob = kzalloc(sizeof(struct _NEGOTIATE_MESSAGE) + 500,
GFP_KERNEL);
if (ntlmssp_blob == NULL) {
rc = -ENOMEM;
goto ssetup_exit;
}
rc = build_ntlmssp_auth_blob(ntlmssp_blob, &blob_length, ses,
nls_cp);
if (rc) {
cifs_dbg(FYI, "build_ntlmssp_auth_blob failed %d\n",
rc);
goto ssetup_exit; /* BB double check error handling */
}
if (use_spnego) {
/* blob_length = build_spnego_ntlmssp_blob(
&security_blob,
blob_length,
ntlmssp_blob); */
cifs_dbg(VFS, "spnego not supported for SMB2 yet\n");
rc = -EOPNOTSUPP;
kfree(ntlmssp_blob);
goto ssetup_exit;
} else {
security_blob = ntlmssp_blob;
}
iov[1].iov_base = security_blob;
iov[1].iov_len = blob_length;
} else {
cifs_dbg(VFS, "illegal ntlmssp phase\n");
rc = -EIO;
goto ssetup_exit;
}
/* Testing shows that buffer offset must be at location of Buffer[0] */
req->SecurityBufferOffset =
cpu_to_le16(sizeof(struct smb2_sess_setup_req) -
1 /* pad */ - 4 /* rfc1001 len */);
req->SecurityBufferLength = cpu_to_le16(blob_length);
inc_rfc1001_len(req, blob_length - 1 /* pad */);
/* BB add code to build os and lm fields */
rc = SendReceive2(xid, ses, iov, 2, &resp_buftype,
CIFS_LOG_ERROR | CIFS_NEG_OP);
kfree(security_blob);
rsp = (struct smb2_sess_setup_rsp *)iov[0].iov_base;
ses->Suid = rsp->hdr.SessionId;
if (resp_buftype != CIFS_NO_BUFFER &&
rsp->hdr.Status == STATUS_MORE_PROCESSING_REQUIRED) {
if (phase != NtLmNegotiate) {
cifs_dbg(VFS, "Unexpected more processing error\n");
goto ssetup_exit;
}
if (offsetof(struct smb2_sess_setup_rsp, Buffer) - 4 !=
le16_to_cpu(rsp->SecurityBufferOffset)) {
cifs_dbg(VFS, "Invalid security buffer offset %d\n",
le16_to_cpu(rsp->SecurityBufferOffset));
rc = -EIO;
goto ssetup_exit;
}
/* NTLMSSP Negotiate sent now processing challenge (response) */
phase = NtLmChallenge; /* process ntlmssp challenge */
rc = 0; /* MORE_PROCESSING is not an error here but expected */
rc = decode_ntlmssp_challenge(rsp->Buffer,
le16_to_cpu(rsp->SecurityBufferLength), ses);
}
/*
* BB eventually add code for SPNEGO decoding of NtlmChallenge blob,
* but at least the raw NTLMSSP case works.
*/
/*
* No tcon so can't do
* cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_fail[SMB2...]);
*/
if (rc != 0)
goto ssetup_exit;
ses->session_flags = le16_to_cpu(rsp->SessionFlags);
if (ses->session_flags & SMB2_SESSION_FLAG_ENCRYPT_DATA)
cifs_dbg(VFS, "SMB3 encryption not supported yet\n");
ssetup_exit:
free_rsp_buf(resp_buftype, rsp);
/* if ntlmssp, and negotiate succeeded, proceed to authenticate phase */
if ((phase == NtLmChallenge) && (rc == 0))
goto ssetup_ntlmssp_authenticate;
if (!rc) {
mutex_lock(&server->srv_mutex);
if (server->sign && server->ops->generate_signingkey) {
rc = server->ops->generate_signingkey(ses);
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
if (rc) {
cifs_dbg(FYI,
"SMB3 session key generation failed\n");
mutex_unlock(&server->srv_mutex);
goto keygen_exit;
}
}
if (!server->session_estab) {
server->sequence_number = 0x2;
server->session_estab = true;
}
mutex_unlock(&server->srv_mutex);
cifs_dbg(FYI, "SMB2/3 session established successfully\n");
spin_lock(&GlobalMid_Lock);
ses->status = CifsGood;
ses->need_reconnect = false;
spin_unlock(&GlobalMid_Lock);
}
keygen_exit:
if (!server->sign) {
kfree(ses->auth_key.response);
ses->auth_key.response = NULL;
}
if (spnego_key) {
key_invalidate(spnego_key);
key_put(spnego_key);
}
kfree(ses->ntlmssp);
return rc;
}
int
SMB2_logoff(const unsigned int xid, struct cifs_ses *ses)
{
struct smb2_logoff_req *req; /* response is also trivial struct */
int rc = 0;
struct TCP_Server_Info *server;
cifs_dbg(FYI, "disconnect session %p\n", ses);
if (ses && (ses->server))
server = ses->server;
else
return -EIO;
/* no need to send SMB logoff if uid already closed due to reconnect */
if (ses->need_reconnect)
goto smb2_session_already_dead;
rc = small_smb2_init(SMB2_LOGOFF, NULL, (void **) &req);
if (rc)
return rc;
/* since no tcon, smb2_init can not do this, so do here */
req->hdr.SessionId = ses->Suid;
if (server->sign)
req->hdr.Flags |= SMB2_FLAGS_SIGNED;
rc = SendReceiveNoRsp(xid, ses, (char *) &req->hdr, 0);
/*
* No tcon so can't do
* cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_fail[SMB2...]);
*/
smb2_session_already_dead:
return rc;
}
static inline void cifs_stats_fail_inc(struct cifs_tcon *tcon, uint16_t code)
{
cifs_stats_inc(&tcon->stats.smb2_stats.smb2_com_failed[code]);
}
#define MAX_SHARENAME_LENGTH (255 /* server */ + 80 /* share */ + 1 /* NULL */)
/* These are similar values to what Windows uses */
static inline void init_copy_chunk_defaults(struct cifs_tcon *tcon)
{
tcon->max_chunks = 256;
tcon->max_bytes_chunk = 1048576;
tcon->max_bytes_copy = 16777216;
}
int
SMB2_tcon(const unsigned int xid, struct cifs_ses *ses, const char *tree,
struct cifs_tcon *tcon, const struct nls_table *cp)
{
struct smb2_tree_connect_req *req;
struct smb2_tree_connect_rsp *rsp = NULL;
struct kvec iov[2];
int rc = 0;
int resp_buftype;
int unc_path_len;
struct TCP_Server_Info *server;
__le16 *unc_path = NULL;
cifs_dbg(FYI, "TCON\n");
if ((ses->server) && tree)
server = ses->server;
else
return -EIO;
if (tcon && tcon->bad_network_name)
return -ENOENT;
if ((tcon && tcon->seal) &&
((ses->server->capabilities & SMB2_GLOBAL_CAP_ENCRYPTION) == 0)) {
cifs_dbg(VFS, "encryption requested but no server support");
return -EOPNOTSUPP;
}
unc_path = kmalloc(MAX_SHARENAME_LENGTH * 2, GFP_KERNEL);
if (unc_path == NULL)
return -ENOMEM;
unc_path_len = cifs_strtoUTF16(unc_path, tree, strlen(tree), cp) + 1;
unc_path_len *= 2;
if (unc_path_len < 2) {
kfree(unc_path);
return -EINVAL;
}
rc = small_smb2_init(SMB2_TREE_CONNECT, tcon, (void **) &req);
if (rc) {
kfree(unc_path);
return rc;
}
if (tcon == NULL) {
/* since no tcon, smb2_init can not do this, so do here */
req->hdr.SessionId = ses->Suid;
/* if (ses->server->sec_mode & SECMODE_SIGN_REQUIRED)
req->hdr.Flags |= SMB2_FLAGS_SIGNED; */
}
iov[0].iov_base = (char *)req;
/* 4 for rfc1002 length field and 1 for pad */
iov[0].iov_len = get_rfc1002_length(req) + 4 - 1;
/* Testing shows that buffer offset must be at location of Buffer[0] */
req->PathOffset = cpu_to_le16(sizeof(struct smb2_tree_connect_req)
- 1 /* pad */ - 4 /* do not count rfc1001 len field */);
req->PathLength = cpu_to_le16(unc_path_len - 2);
iov[1].iov_base = unc_path;
iov[1].iov_len = unc_path_len;
inc_rfc1001_len(req, unc_path_len - 1 /* pad */);
rc = SendReceive2(xid, ses, iov, 2, &resp_buftype, 0);
rsp = (struct smb2_tree_connect_rsp *)iov[0].iov_base;
if (rc != 0) {
if (tcon) {
cifs_stats_fail_inc(tcon, SMB2_TREE_CONNECT_HE);
tcon->need_reconnect = true;
}
goto tcon_error_exit;
}
if (tcon == NULL) {
ses->ipc_tid = rsp->hdr.TreeId;
goto tcon_exit;
}
if (rsp->ShareType & SMB2_SHARE_TYPE_DISK)
cifs_dbg(FYI, "connection to disk share\n");
else if (rsp->ShareType & SMB2_SHARE_TYPE_PIPE) {
tcon->ipc = true;
cifs_dbg(FYI, "connection to pipe share\n");
} else if (rsp->ShareType & SMB2_SHARE_TYPE_PRINT) {
tcon->print = true;
cifs_dbg(FYI, "connection to printer\n");
} else {
cifs_dbg(VFS, "unknown share type %d\n", rsp->ShareType);
rc = -EOPNOTSUPP;
goto tcon_error_exit;
}
tcon->share_flags = le32_to_cpu(rsp->ShareFlags);
tcon->capabilities = rsp->Capabilities; /* we keep caps little endian */
tcon->maximal_access = le32_to_cpu(rsp->MaximalAccess);