/*
* fs/cifs/smb2pdu.c
*
* Copyright (C) International Business Machines Corp., 2009, 2011
* 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/uaccess.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"
/*
* 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;
hdr->TreeId = tcon->tid;
/* Uid is not converted */
if (tcon->ses)
hdr->SessionId = tcon->ses->Suid;
/* BB check following DFS flags BB */
/* BB do we have to add check for SHI1005_FLAGS_DFS_ROOT too? */
/* if (tcon->share_flags & SHI1005_FLAGS_DFS)
hdr->Flags |= SMB2_FLAGS_DFS_OPERATIONS; */
/* BB how does SMB2 do case sensitive? */
/* if (tcon->nocase)
hdr->Flags |= SMBFLG_CASELESS; */
/* if (tcon->ses && tcon->ses->server &&
(tcon->ses->server->sec_mode & SECMODE_SIGN_REQUIRED))
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;
/* BB add missing code here */
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;
}
static void
free_rsp_buf(int resp_buftype, void *rsp)
{
if (resp_buftype == CIFS_SMALL_BUFFER)
cifs_small_buf_release(rsp);
else if (resp_buftype == CIFS_LARGE_BUFFER)
cifs_buf_release(rsp);
}
#define SMB2_NUM_PROT 1
#define SMB2_PROT 0
#define SMB21_PROT 1
#define BAD_PROT 0xFFFF
#define SMB2_PROT_ID 0x0202
#define SMB21_PROT_ID 0x0210
#define BAD_PROT_ID 0xFFFF
static struct {
int index;
__le16 name;
} smb2protocols[] = {
{SMB2_PROT, cpu_to_le16(SMB2_PROT_ID)},
{SMB21_PROT, cpu_to_le16(SMB21_PROT_ID)},
{BAD_PROT, cpu_to_le16(BAD_PROT_ID)}
};
/*
*
* 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;
unsigned int sec_flags;
u16 i;
u16 temp = 0;
int blob_offset, blob_length;
char *security_blob;
int flags = CIFS_NEG_OP;
cFYI(1, "Negotiate protocol");
if (ses->server)
server = ses->server;
else {
rc = -EIO;
return rc;
}
rc = small_smb2_init(SMB2_NEGOTIATE, NULL, (void **) &req);
if (rc)
return rc;
/* if any of auth flags (ie not sign or seal) are overriden use them */
if (ses->overrideSecFlg & (~(CIFSSEC_MUST_SIGN | CIFSSEC_MUST_SEAL)))
sec_flags = ses->overrideSecFlg; /* BB FIXME fix sign flags?*/
else /* if override flags set only sign/seal OR them with global auth */
sec_flags = global_secflags | ses->overrideSecFlg;
cFYI(1, "sec_flags 0x%x", sec_flags);
req->hdr.SessionId = 0;
for (i = 0; i < SMB2_NUM_PROT; i++)
req->Dialects[i] = smb2protocols[i].name;
req->DialectCount = cpu_to_le16(i);
inc_rfc1001_len(req, i * 2);
/* only one of SMB2 signing flags may be set in SMB2 request */
if ((sec_flags & CIFSSEC_MUST_SIGN) == CIFSSEC_MUST_SIGN)
temp = SMB2_NEGOTIATE_SIGNING_REQUIRED;
else if (sec_flags & CIFSSEC_MAY_SIGN) /* MAY_SIGN is a single flag */
temp = SMB2_NEGOTIATE_SIGNING_ENABLED;
req->SecurityMode = cpu_to_le16(temp);
req->Capabilities = cpu_to_le32(SMB2_GLOBAL_CAP_DFS);
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;
if (rsp == NULL) {
rc = -EIO;
goto neg_exit;
}
cFYI(1, "mode 0x%x", rsp->SecurityMode);
if (rsp->DialectRevision == smb2protocols[SMB21_PROT].name)
cFYI(1, "negotiated smb2.1 dialect");
else if (rsp->DialectRevision == smb2protocols[SMB2_PROT].name)
cFYI(1, "negotiated smb2 dialect");
else {
cERROR(1, "Illegal dialect returned by server %d",
le16_to_cpu(rsp->DialectRevision));
rc = -EIO;
goto neg_exit;
}
server->dialect = le16_to_cpu(rsp->DialectRevision);
server->maxBuf = le32_to_cpu(rsp->MaxTransactSize);
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);
security_blob = smb2_get_data_area_len(&blob_offset, &blob_length,
&rsp->hdr);
if (blob_length == 0) {
cERROR(1, "missing security blob on negprot");
rc = -EIO;
goto neg_exit;
}
#ifdef CONFIG_SMB2_ASN1 /* BB REMOVEME when updated asn1.c ready */
rc = decode_neg_token_init(security_blob, blob_length,
&server->sec_type);
if (rc == 1)
rc = 0;
else if (rc == 0) {
rc = -EIO;
goto neg_exit;
}
#endif
neg_exit:
free_rsp_buf(resp_buftype, rsp);
return rc;
}
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;
__le32 phase = NtLmNegotiate; /* NTLMSSP, if needed, is multistage */
struct TCP_Server_Info *server;
unsigned int sec_flags;
u8 temp = 0;
u16 blob_length = 0;
char *security_blob;
char *ntlmssp_blob = NULL;
bool use_spnego = false; /* else use raw ntlmssp */
cFYI(1, "Session Setup");
if (ses->server)
server = ses->server;
else {
rc = -EIO;
return rc;
}
/*
* 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->server->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;
/* if any of auth flags (ie not sign or seal) are overriden use them */
if (ses->overrideSecFlg & (~(CIFSSEC_MUST_SIGN | CIFSSEC_MUST_SEAL)))
sec_flags = ses->overrideSecFlg; /* BB FIXME fix sign flags?*/
else /* if override flags set only sign/seal OR them with global auth */
sec_flags = global_secflags | ses->overrideSecFlg;
cFYI(1, "sec_flags 0x%x", sec_flags);
req->hdr.SessionId = 0; /* First session, not a reauthenticate */
req->VcNumber = 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 ((sec_flags & CIFSSEC_MUST_SIGN) == CIFSSEC_MUST_SIGN)
temp = SMB2_NEGOTIATE_SIGNING_REQUIRED;
else if (ses->server->sec_mode & SMB2_NEGOTIATE_SIGNING_REQUIRED)
temp = SMB2_NEGOTIATE_SIGNING_REQUIRED;
else if (sec_flags & CIFSSEC_MAY_SIGN) /* MAY_SIGN is a single flag */
temp = SMB2_NEGOTIATE_SIGNING_ENABLED;
req->SecurityMode = temp;
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 (phase == NtLmNegotiate) {
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 */
cERROR(1, "spnego not supported for SMB2 yet");
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;
}
} else if (phase == NtLmAuthenticate) {
req->hdr.SessionId = ses->Suid;
ntlmssp_blob = kzalloc(sizeof(struct _NEGOTIATE_MESSAGE) + 500,
GFP_KERNEL);
if (ntlmssp_blob == NULL) {
cERROR(1, "failed to malloc ntlmssp blob");
rc = -ENOMEM;
goto ssetup_exit;
}
rc = build_ntlmssp_auth_blob(ntlmssp_blob, &blob_length, ses,
nls_cp);
if (rc) {
cFYI(1, "build_ntlmssp_auth_blob failed %d", rc);
goto ssetup_exit; /* BB double check error handling */
}
if (use_spnego) {
/* blob_length = build_spnego_ntlmssp_blob(
&security_blob,
blob_length,
ntlmssp_blob); */
cERROR(1, "spnego not supported for SMB2 yet");
rc = -EOPNOTSUPP;
kfree(ntlmssp_blob);
goto ssetup_exit;
} else {
security_blob = ntlmssp_blob;
}
} else {
cERROR(1, "illegal ntlmssp phase");
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);
iov[1].iov_base = security_blob;
iov[1].iov_len = 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);
kfree(security_blob);
rsp = (struct smb2_sess_setup_rsp *)iov[0].iov_base;
if (rsp->hdr.Status == STATUS_MORE_PROCESSING_REQUIRED) {
if (phase != NtLmNegotiate) {
cERROR(1, "Unexpected more processing error");
goto ssetup_exit;
}
if (offsetof(struct smb2_sess_setup_rsp, Buffer) - 4 !=
le16_to_cpu(rsp->SecurityBufferOffset)) {
cERROR(1, "Invalid security buffer offset %d",
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 */
ses->Suid = rsp->hdr.SessionId;
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;
if (rsp == NULL) {
rc = -EIO;
goto ssetup_exit;
}
ses->session_flags = le16_to_cpu(rsp->SessionFlags);
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;
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;
cFYI(1, "disconnect session %p", ses);
if (ses && (ses->server))
server = ses->server;
else
return -EIO;
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;
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...]);
*/
return rc;
}
