linux-zen-server/fs/cifs/smb2misc.c

945 lines
26 KiB
C

// SPDX-License-Identifier: LGPL-2.1
/*
*
* Copyright (C) International Business Machines Corp., 2002,2011
* Etersoft, 2012
* Author(s): Steve French (sfrench@us.ibm.com)
* Pavel Shilovsky (pshilovsky@samba.org) 2012
*
*/
#include <linux/ctype.h>
#include "cifsglob.h"
#include "cifsproto.h"
#include "smb2proto.h"
#include "cifs_debug.h"
#include "cifs_unicode.h"
#include "smb2status.h"
#include "smb2glob.h"
#include "nterr.h"
#include "cached_dir.h"
static int
check_smb2_hdr(struct smb2_hdr *shdr, __u64 mid)
{
__u64 wire_mid = le64_to_cpu(shdr->MessageId);
/*
* Make sure that this really is an SMB, that it is a response,
* and that the message ids match.
*/
if ((shdr->ProtocolId == SMB2_PROTO_NUMBER) &&
(mid == wire_mid)) {
if (shdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
return 0;
else {
/* only one valid case where server sends us request */
if (shdr->Command == SMB2_OPLOCK_BREAK)
return 0;
else
cifs_dbg(VFS, "Received Request not response\n");
}
} else { /* bad signature or mid */
if (shdr->ProtocolId != SMB2_PROTO_NUMBER)
cifs_dbg(VFS, "Bad protocol string signature header %x\n",
le32_to_cpu(shdr->ProtocolId));
if (mid != wire_mid)
cifs_dbg(VFS, "Mids do not match: %llu and %llu\n",
mid, wire_mid);
}
cifs_dbg(VFS, "Bad SMB detected. The Mid=%llu\n", wire_mid);
return 1;
}
/*
* The following table defines the expected "StructureSize" of SMB2 responses
* in order by SMB2 command. This is similar to "wct" in SMB/CIFS responses.
*
* Note that commands are defined in smb2pdu.h in le16 but the array below is
* indexed by command in host byte order
*/
static const __le16 smb2_rsp_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
/* SMB2_NEGOTIATE */ cpu_to_le16(65),
/* SMB2_SESSION_SETUP */ cpu_to_le16(9),
/* SMB2_LOGOFF */ cpu_to_le16(4),
/* SMB2_TREE_CONNECT */ cpu_to_le16(16),
/* SMB2_TREE_DISCONNECT */ cpu_to_le16(4),
/* SMB2_CREATE */ cpu_to_le16(89),
/* SMB2_CLOSE */ cpu_to_le16(60),
/* SMB2_FLUSH */ cpu_to_le16(4),
/* SMB2_READ */ cpu_to_le16(17),
/* SMB2_WRITE */ cpu_to_le16(17),
/* SMB2_LOCK */ cpu_to_le16(4),
/* SMB2_IOCTL */ cpu_to_le16(49),
/* BB CHECK this ... not listed in documentation */
/* SMB2_CANCEL */ cpu_to_le16(0),
/* SMB2_ECHO */ cpu_to_le16(4),
/* SMB2_QUERY_DIRECTORY */ cpu_to_le16(9),
/* SMB2_CHANGE_NOTIFY */ cpu_to_le16(9),
/* SMB2_QUERY_INFO */ cpu_to_le16(9),
/* SMB2_SET_INFO */ cpu_to_le16(2),
/* BB FIXME can also be 44 for lease break */
/* SMB2_OPLOCK_BREAK */ cpu_to_le16(24)
};
#define SMB311_NEGPROT_BASE_SIZE (sizeof(struct smb2_hdr) + sizeof(struct smb2_negotiate_rsp))
static __u32 get_neg_ctxt_len(struct smb2_hdr *hdr, __u32 len,
__u32 non_ctxlen)
{
__u16 neg_count;
__u32 nc_offset, size_of_pad_before_neg_ctxts;
struct smb2_negotiate_rsp *pneg_rsp = (struct smb2_negotiate_rsp *)hdr;
/* Negotiate contexts are only valid for latest dialect SMB3.11 */
neg_count = le16_to_cpu(pneg_rsp->NegotiateContextCount);
if ((neg_count == 0) ||
(pneg_rsp->DialectRevision != cpu_to_le16(SMB311_PROT_ID)))
return 0;
/*
* if SPNEGO blob present (ie the RFC2478 GSS info which indicates
* which security mechanisms the server supports) make sure that
* the negotiate contexts start after it
*/
nc_offset = le32_to_cpu(pneg_rsp->NegotiateContextOffset);
/*
* non_ctxlen is at least shdr->StructureSize + pdu->StructureSize2
* and the latter is 1 byte bigger than the fix-sized area of the
* NEGOTIATE response
*/
if (nc_offset + 1 < non_ctxlen) {
pr_warn_once("Invalid negotiate context offset %d\n", nc_offset);
return 0;
} else if (nc_offset + 1 == non_ctxlen) {
cifs_dbg(FYI, "no SPNEGO security blob in negprot rsp\n");
size_of_pad_before_neg_ctxts = 0;
} else if (non_ctxlen == SMB311_NEGPROT_BASE_SIZE + 1)
/* has padding, but no SPNEGO blob */
size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen + 1;
else
size_of_pad_before_neg_ctxts = nc_offset - non_ctxlen;
/* Verify that at least minimal negotiate contexts fit within frame */
if (len < nc_offset + (neg_count * sizeof(struct smb2_neg_context))) {
pr_warn_once("negotiate context goes beyond end\n");
return 0;
}
cifs_dbg(FYI, "length of negcontexts %d pad %d\n",
len - nc_offset, size_of_pad_before_neg_ctxts);
/* length of negcontexts including pad from end of sec blob to them */
return (len - nc_offset) + size_of_pad_before_neg_ctxts;
}
int
smb2_check_message(char *buf, unsigned int len, struct TCP_Server_Info *server)
{
struct TCP_Server_Info *pserver;
struct smb2_hdr *shdr = (struct smb2_hdr *)buf;
struct smb2_pdu *pdu = (struct smb2_pdu *)shdr;
int hdr_size = sizeof(struct smb2_hdr);
int pdu_size = sizeof(struct smb2_pdu);
int command;
__u32 calc_len; /* calculated length */
__u64 mid;
/* If server is a channel, select the primary channel */
pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
/*
* Add function to do table lookup of StructureSize by command
* ie Validate the wct via smb2_struct_sizes table above
*/
if (shdr->ProtocolId == SMB2_TRANSFORM_PROTO_NUM) {
struct smb2_transform_hdr *thdr =
(struct smb2_transform_hdr *)buf;
struct cifs_ses *ses = NULL;
struct cifs_ses *iter;
/* decrypt frame now that it is completely read in */
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(iter, &pserver->smb_ses_list, smb_ses_list) {
if (iter->Suid == le64_to_cpu(thdr->SessionId)) {
ses = iter;
break;
}
}
spin_unlock(&cifs_tcp_ses_lock);
if (!ses) {
cifs_dbg(VFS, "no decryption - session id not found\n");
return 1;
}
}
mid = le64_to_cpu(shdr->MessageId);
if (len < pdu_size) {
if ((len >= hdr_size)
&& (shdr->Status != 0)) {
pdu->StructureSize2 = 0;
/*
* As with SMB/CIFS, on some error cases servers may
* not return wct properly
*/
return 0;
} else {
cifs_dbg(VFS, "Length less than SMB header size\n");
}
return 1;
}
if (len > CIFSMaxBufSize + MAX_SMB2_HDR_SIZE) {
cifs_dbg(VFS, "SMB length greater than maximum, mid=%llu\n",
mid);
return 1;
}
if (check_smb2_hdr(shdr, mid))
return 1;
if (shdr->StructureSize != SMB2_HEADER_STRUCTURE_SIZE) {
cifs_dbg(VFS, "Invalid structure size %u\n",
le16_to_cpu(shdr->StructureSize));
return 1;
}
command = le16_to_cpu(shdr->Command);
if (command >= NUMBER_OF_SMB2_COMMANDS) {
cifs_dbg(VFS, "Invalid SMB2 command %d\n", command);
return 1;
}
if (smb2_rsp_struct_sizes[command] != pdu->StructureSize2) {
if (command != SMB2_OPLOCK_BREAK_HE && (shdr->Status == 0 ||
pdu->StructureSize2 != SMB2_ERROR_STRUCTURE_SIZE2_LE)) {
/* error packets have 9 byte structure size */
cifs_dbg(VFS, "Invalid response size %u for command %d\n",
le16_to_cpu(pdu->StructureSize2), command);
return 1;
} else if (command == SMB2_OPLOCK_BREAK_HE
&& (shdr->Status == 0)
&& (le16_to_cpu(pdu->StructureSize2) != 44)
&& (le16_to_cpu(pdu->StructureSize2) != 36)) {
/* special case for SMB2.1 lease break message */
cifs_dbg(VFS, "Invalid response size %d for oplock break\n",
le16_to_cpu(pdu->StructureSize2));
return 1;
}
}
calc_len = smb2_calc_size(buf);
/* For SMB2_IOCTL, OutputOffset and OutputLength are optional, so might
* be 0, and not a real miscalculation */
if (command == SMB2_IOCTL_HE && calc_len == 0)
return 0;
if (command == SMB2_NEGOTIATE_HE)
calc_len += get_neg_ctxt_len(shdr, len, calc_len);
if (len != calc_len) {
/* create failed on symlink */
if (command == SMB2_CREATE_HE &&
shdr->Status == STATUS_STOPPED_ON_SYMLINK)
return 0;
/* Windows 7 server returns 24 bytes more */
if (calc_len + 24 == len && command == SMB2_OPLOCK_BREAK_HE)
return 0;
/* server can return one byte more due to implied bcc[0] */
if (calc_len == len + 1)
return 0;
/*
* Some windows servers (win2016) will pad also the final
* PDU in a compound to 8 bytes.
*/
if (ALIGN(calc_len, 8) == len)
return 0;
/*
* MacOS server pads after SMB2.1 write response with 3 bytes
* of junk. Other servers match RFC1001 len to actual
* SMB2/SMB3 frame length (header + smb2 response specific data)
* Some windows servers also pad up to 8 bytes when compounding.
*/
if (calc_len < len)
return 0;
/* Only log a message if len was really miscalculated */
if (unlikely(cifsFYI))
cifs_dbg(FYI, "Server response too short: calculated "
"length %u doesn't match read length %u (cmd=%d, mid=%llu)\n",
calc_len, len, command, mid);
else
pr_warn("Server response too short: calculated length "
"%u doesn't match read length %u (cmd=%d, mid=%llu)\n",
calc_len, len, command, mid);
return 1;
}
return 0;
}
/*
* The size of the variable area depends on the offset and length fields
* located in different fields for various SMB2 responses. SMB2 responses
* with no variable length info, show an offset of zero for the offset field.
*/
static const bool has_smb2_data_area[NUMBER_OF_SMB2_COMMANDS] = {
/* SMB2_NEGOTIATE */ true,
/* SMB2_SESSION_SETUP */ true,
/* SMB2_LOGOFF */ false,
/* SMB2_TREE_CONNECT */ false,
/* SMB2_TREE_DISCONNECT */ false,
/* SMB2_CREATE */ true,
/* SMB2_CLOSE */ false,
/* SMB2_FLUSH */ false,
/* SMB2_READ */ true,
/* SMB2_WRITE */ false,
/* SMB2_LOCK */ false,
/* SMB2_IOCTL */ true,
/* SMB2_CANCEL */ false, /* BB CHECK this not listed in documentation */
/* SMB2_ECHO */ false,
/* SMB2_QUERY_DIRECTORY */ true,
/* SMB2_CHANGE_NOTIFY */ true,
/* SMB2_QUERY_INFO */ true,
/* SMB2_SET_INFO */ false,
/* SMB2_OPLOCK_BREAK */ false
};
/*
* Returns the pointer to the beginning of the data area. Length of the data
* area and the offset to it (from the beginning of the smb are also returned.
*/
char *
smb2_get_data_area_len(int *off, int *len, struct smb2_hdr *shdr)
{
*off = 0;
*len = 0;
/* error responses do not have data area */
if (shdr->Status && shdr->Status != STATUS_MORE_PROCESSING_REQUIRED &&
(((struct smb2_err_rsp *)shdr)->StructureSize) ==
SMB2_ERROR_STRUCTURE_SIZE2_LE)
return NULL;
/*
* Following commands have data areas so we have to get the location
* of the data buffer offset and data buffer length for the particular
* command.
*/
switch (shdr->Command) {
case SMB2_NEGOTIATE:
*off = le16_to_cpu(
((struct smb2_negotiate_rsp *)shdr)->SecurityBufferOffset);
*len = le16_to_cpu(
((struct smb2_negotiate_rsp *)shdr)->SecurityBufferLength);
break;
case SMB2_SESSION_SETUP:
*off = le16_to_cpu(
((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferOffset);
*len = le16_to_cpu(
((struct smb2_sess_setup_rsp *)shdr)->SecurityBufferLength);
break;
case SMB2_CREATE:
*off = le32_to_cpu(
((struct smb2_create_rsp *)shdr)->CreateContextsOffset);
*len = le32_to_cpu(
((struct smb2_create_rsp *)shdr)->CreateContextsLength);
break;
case SMB2_QUERY_INFO:
*off = le16_to_cpu(
((struct smb2_query_info_rsp *)shdr)->OutputBufferOffset);
*len = le32_to_cpu(
((struct smb2_query_info_rsp *)shdr)->OutputBufferLength);
break;
case SMB2_READ:
/* TODO: is this a bug ? */
*off = ((struct smb2_read_rsp *)shdr)->DataOffset;
*len = le32_to_cpu(((struct smb2_read_rsp *)shdr)->DataLength);
break;
case SMB2_QUERY_DIRECTORY:
*off = le16_to_cpu(
((struct smb2_query_directory_rsp *)shdr)->OutputBufferOffset);
*len = le32_to_cpu(
((struct smb2_query_directory_rsp *)shdr)->OutputBufferLength);
break;
case SMB2_IOCTL:
*off = le32_to_cpu(
((struct smb2_ioctl_rsp *)shdr)->OutputOffset);
*len = le32_to_cpu(
((struct smb2_ioctl_rsp *)shdr)->OutputCount);
break;
case SMB2_CHANGE_NOTIFY:
*off = le16_to_cpu(
((struct smb2_change_notify_rsp *)shdr)->OutputBufferOffset);
*len = le32_to_cpu(
((struct smb2_change_notify_rsp *)shdr)->OutputBufferLength);
break;
default:
cifs_dbg(VFS, "no length check for command %d\n", le16_to_cpu(shdr->Command));
break;
}
/*
* Invalid length or offset probably means data area is invalid, but
* we have little choice but to ignore the data area in this case.
*/
if (*off > 4096) {
cifs_dbg(VFS, "offset %d too large, data area ignored\n", *off);
*len = 0;
*off = 0;
} else if (*off < 0) {
cifs_dbg(VFS, "negative offset %d to data invalid ignore data area\n",
*off);
*off = 0;
*len = 0;
} else if (*len < 0) {
cifs_dbg(VFS, "negative data length %d invalid, data area ignored\n",
*len);
*len = 0;
} else if (*len > 128 * 1024) {
cifs_dbg(VFS, "data area larger than 128K: %d\n", *len);
*len = 0;
}
/* return pointer to beginning of data area, ie offset from SMB start */
if ((*off != 0) && (*len != 0))
return (char *)shdr + *off;
else
return NULL;
}
/*
* Calculate the size of the SMB message based on the fixed header
* portion, the number of word parameters and the data portion of the message.
*/
unsigned int
smb2_calc_size(void *buf)
{
struct smb2_pdu *pdu = buf;
struct smb2_hdr *shdr = &pdu->hdr;
int offset; /* the offset from the beginning of SMB to data area */
int data_length; /* the length of the variable length data area */
/* Structure Size has already been checked to make sure it is 64 */
int len = le16_to_cpu(shdr->StructureSize);
/*
* StructureSize2, ie length of fixed parameter area has already
* been checked to make sure it is the correct length.
*/
len += le16_to_cpu(pdu->StructureSize2);
if (has_smb2_data_area[le16_to_cpu(shdr->Command)] == false)
goto calc_size_exit;
smb2_get_data_area_len(&offset, &data_length, shdr);
cifs_dbg(FYI, "SMB2 data length %d offset %d\n", data_length, offset);
if (data_length > 0) {
/*
* Check to make sure that data area begins after fixed area,
* Note that last byte of the fixed area is part of data area
* for some commands, typically those with odd StructureSize,
* so we must add one to the calculation.
*/
if (offset + 1 < len) {
cifs_dbg(VFS, "data area offset %d overlaps SMB2 header %d\n",
offset + 1, len);
data_length = 0;
} else {
len = offset + data_length;
}
}
calc_size_exit:
cifs_dbg(FYI, "SMB2 len %d\n", len);
return len;
}
/* Note: caller must free return buffer */
__le16 *
cifs_convert_path_to_utf16(const char *from, struct cifs_sb_info *cifs_sb)
{
int len;
const char *start_of_path;
__le16 *to;
int map_type;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SFM_CHR)
map_type = SFM_MAP_UNI_RSVD;
else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
map_type = SFU_MAP_UNI_RSVD;
else
map_type = NO_MAP_UNI_RSVD;
/* Windows doesn't allow paths beginning with \ */
if (from[0] == '\\')
start_of_path = from + 1;
/* SMB311 POSIX extensions paths do not include leading slash */
else if (cifs_sb_master_tlink(cifs_sb) &&
cifs_sb_master_tcon(cifs_sb)->posix_extensions &&
(from[0] == '/')) {
start_of_path = from + 1;
} else
start_of_path = from;
to = cifs_strndup_to_utf16(start_of_path, PATH_MAX, &len,
cifs_sb->local_nls, map_type);
return to;
}
__le32
smb2_get_lease_state(struct cifsInodeInfo *cinode)
{
__le32 lease = 0;
if (CIFS_CACHE_WRITE(cinode))
lease |= SMB2_LEASE_WRITE_CACHING_LE;
if (CIFS_CACHE_HANDLE(cinode))
lease |= SMB2_LEASE_HANDLE_CACHING_LE;
if (CIFS_CACHE_READ(cinode))
lease |= SMB2_LEASE_READ_CACHING_LE;
return lease;
}
struct smb2_lease_break_work {
struct work_struct lease_break;
struct tcon_link *tlink;
__u8 lease_key[16];
__le32 lease_state;
};
static void
cifs_ses_oplock_break(struct work_struct *work)
{
struct smb2_lease_break_work *lw = container_of(work,
struct smb2_lease_break_work, lease_break);
int rc = 0;
rc = SMB2_lease_break(0, tlink_tcon(lw->tlink), lw->lease_key,
lw->lease_state);
cifs_dbg(FYI, "Lease release rc %d\n", rc);
cifs_put_tlink(lw->tlink);
kfree(lw);
}
static void
smb2_queue_pending_open_break(struct tcon_link *tlink, __u8 *lease_key,
__le32 new_lease_state)
{
struct smb2_lease_break_work *lw;
lw = kmalloc(sizeof(struct smb2_lease_break_work), GFP_KERNEL);
if (!lw) {
cifs_put_tlink(tlink);
return;
}
INIT_WORK(&lw->lease_break, cifs_ses_oplock_break);
lw->tlink = tlink;
lw->lease_state = new_lease_state;
memcpy(lw->lease_key, lease_key, SMB2_LEASE_KEY_SIZE);
queue_work(cifsiod_wq, &lw->lease_break);
}
static bool
smb2_tcon_has_lease(struct cifs_tcon *tcon, struct smb2_lease_break *rsp)
{
__u8 lease_state;
struct cifsFileInfo *cfile;
struct cifsInodeInfo *cinode;
int ack_req = le32_to_cpu(rsp->Flags &
SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
lease_state = le32_to_cpu(rsp->NewLeaseState);
list_for_each_entry(cfile, &tcon->openFileList, tlist) {
cinode = CIFS_I(d_inode(cfile->dentry));
if (memcmp(cinode->lease_key, rsp->LeaseKey,
SMB2_LEASE_KEY_SIZE))
continue;
cifs_dbg(FYI, "found in the open list\n");
cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
lease_state);
if (ack_req)
cfile->oplock_break_cancelled = false;
else
cfile->oplock_break_cancelled = true;
set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK, &cinode->flags);
cfile->oplock_epoch = le16_to_cpu(rsp->Epoch);
cfile->oplock_level = lease_state;
cifs_queue_oplock_break(cfile);
return true;
}
return false;
}
static struct cifs_pending_open *
smb2_tcon_find_pending_open_lease(struct cifs_tcon *tcon,
struct smb2_lease_break *rsp)
{
__u8 lease_state = le32_to_cpu(rsp->NewLeaseState);
int ack_req = le32_to_cpu(rsp->Flags &
SMB2_NOTIFY_BREAK_LEASE_FLAG_ACK_REQUIRED);
struct cifs_pending_open *open;
struct cifs_pending_open *found = NULL;
list_for_each_entry(open, &tcon->pending_opens, olist) {
if (memcmp(open->lease_key, rsp->LeaseKey,
SMB2_LEASE_KEY_SIZE))
continue;
if (!found && ack_req) {
found = open;
}
cifs_dbg(FYI, "found in the pending open list\n");
cifs_dbg(FYI, "lease key match, lease break 0x%x\n",
lease_state);
open->oplock = lease_state;
}
return found;
}
static bool
smb2_is_valid_lease_break(char *buffer, struct TCP_Server_Info *server)
{
struct smb2_lease_break *rsp = (struct smb2_lease_break *)buffer;
struct TCP_Server_Info *pserver;
struct cifs_ses *ses;
struct cifs_tcon *tcon;
struct cifs_pending_open *open;
cifs_dbg(FYI, "Checking for lease break\n");
/* If server is a channel, select the primary channel */
pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
/* look up tcon based on tid & uid */
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
spin_lock(&tcon->open_file_lock);
cifs_stats_inc(
&tcon->stats.cifs_stats.num_oplock_brks);
if (smb2_tcon_has_lease(tcon, rsp)) {
spin_unlock(&tcon->open_file_lock);
spin_unlock(&cifs_tcp_ses_lock);
return true;
}
open = smb2_tcon_find_pending_open_lease(tcon,
rsp);
if (open) {
__u8 lease_key[SMB2_LEASE_KEY_SIZE];
struct tcon_link *tlink;
tlink = cifs_get_tlink(open->tlink);
memcpy(lease_key, open->lease_key,
SMB2_LEASE_KEY_SIZE);
spin_unlock(&tcon->open_file_lock);
spin_unlock(&cifs_tcp_ses_lock);
smb2_queue_pending_open_break(tlink,
lease_key,
rsp->NewLeaseState);
return true;
}
spin_unlock(&tcon->open_file_lock);
if (cached_dir_lease_break(tcon, rsp->LeaseKey)) {
spin_unlock(&cifs_tcp_ses_lock);
return true;
}
}
}
spin_unlock(&cifs_tcp_ses_lock);
cifs_dbg(FYI, "Can not process lease break - no lease matched\n");
trace_smb3_lease_not_found(le32_to_cpu(rsp->CurrentLeaseState),
le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
le64_to_cpu(rsp->hdr.SessionId),
*((u64 *)rsp->LeaseKey),
*((u64 *)&rsp->LeaseKey[8]));
return false;
}
bool
smb2_is_valid_oplock_break(char *buffer, struct TCP_Server_Info *server)
{
struct smb2_oplock_break *rsp = (struct smb2_oplock_break *)buffer;
struct TCP_Server_Info *pserver;
struct cifs_ses *ses;
struct cifs_tcon *tcon;
struct cifsInodeInfo *cinode;
struct cifsFileInfo *cfile;
cifs_dbg(FYI, "Checking for oplock break\n");
if (rsp->hdr.Command != SMB2_OPLOCK_BREAK)
return false;
if (rsp->StructureSize !=
smb2_rsp_struct_sizes[SMB2_OPLOCK_BREAK_HE]) {
if (le16_to_cpu(rsp->StructureSize) == 44)
return smb2_is_valid_lease_break(buffer, server);
else
return false;
}
cifs_dbg(FYI, "oplock level 0x%x\n", rsp->OplockLevel);
/* If server is a channel, select the primary channel */
pserver = CIFS_SERVER_IS_CHAN(server) ? server->primary_server : server;
/* look up tcon based on tid & uid */
spin_lock(&cifs_tcp_ses_lock);
list_for_each_entry(ses, &pserver->smb_ses_list, smb_ses_list) {
list_for_each_entry(tcon, &ses->tcon_list, tcon_list) {
spin_lock(&tcon->open_file_lock);
list_for_each_entry(cfile, &tcon->openFileList, tlist) {
if (rsp->PersistentFid !=
cfile->fid.persistent_fid ||
rsp->VolatileFid !=
cfile->fid.volatile_fid)
continue;
cifs_dbg(FYI, "file id match, oplock break\n");
cifs_stats_inc(
&tcon->stats.cifs_stats.num_oplock_brks);
cinode = CIFS_I(d_inode(cfile->dentry));
spin_lock(&cfile->file_info_lock);
if (!CIFS_CACHE_WRITE(cinode) &&
rsp->OplockLevel == SMB2_OPLOCK_LEVEL_NONE)
cfile->oplock_break_cancelled = true;
else
cfile->oplock_break_cancelled = false;
set_bit(CIFS_INODE_PENDING_OPLOCK_BREAK,
&cinode->flags);
cfile->oplock_epoch = 0;
cfile->oplock_level = rsp->OplockLevel;
spin_unlock(&cfile->file_info_lock);
cifs_queue_oplock_break(cfile);
spin_unlock(&tcon->open_file_lock);
spin_unlock(&cifs_tcp_ses_lock);
return true;
}
spin_unlock(&tcon->open_file_lock);
}
}
spin_unlock(&cifs_tcp_ses_lock);
cifs_dbg(FYI, "No file id matched, oplock break ignored\n");
trace_smb3_oplock_not_found(0 /* no xid */, rsp->PersistentFid,
le32_to_cpu(rsp->hdr.Id.SyncId.TreeId),
le64_to_cpu(rsp->hdr.SessionId));
return true;
}
void
smb2_cancelled_close_fid(struct work_struct *work)
{
struct close_cancelled_open *cancelled = container_of(work,
struct close_cancelled_open, work);
struct cifs_tcon *tcon = cancelled->tcon;
int rc;
if (cancelled->mid)
cifs_tcon_dbg(VFS, "Close unmatched open for MID:%llu\n",
cancelled->mid);
else
cifs_tcon_dbg(VFS, "Close interrupted close\n");
rc = SMB2_close(0, tcon, cancelled->fid.persistent_fid,
cancelled->fid.volatile_fid);
if (rc)
cifs_tcon_dbg(VFS, "Close cancelled mid failed rc:%d\n", rc);
cifs_put_tcon(tcon);
kfree(cancelled);
}
/*
* Caller should already has an extra reference to @tcon
* This function is used to queue work to close a handle to prevent leaks
* on the server.
* We handle two cases. If an open was interrupted after we sent the
* SMB2_CREATE to the server but before we processed the reply, and second
* if a close was interrupted before we sent the SMB2_CLOSE to the server.
*/
static int
__smb2_handle_cancelled_cmd(struct cifs_tcon *tcon, __u16 cmd, __u64 mid,
__u64 persistent_fid, __u64 volatile_fid)
{
struct close_cancelled_open *cancelled;
cancelled = kzalloc(sizeof(*cancelled), GFP_ATOMIC);
if (!cancelled)
return -ENOMEM;
cancelled->fid.persistent_fid = persistent_fid;
cancelled->fid.volatile_fid = volatile_fid;
cancelled->tcon = tcon;
cancelled->cmd = cmd;
cancelled->mid = mid;
INIT_WORK(&cancelled->work, smb2_cancelled_close_fid);
WARN_ON(queue_work(cifsiod_wq, &cancelled->work) == false);
return 0;
}
int
smb2_handle_cancelled_close(struct cifs_tcon *tcon, __u64 persistent_fid,
__u64 volatile_fid)
{
int rc;
cifs_dbg(FYI, "%s: tc_count=%d\n", __func__, tcon->tc_count);
spin_lock(&cifs_tcp_ses_lock);
if (tcon->tc_count <= 0) {
struct TCP_Server_Info *server = NULL;
WARN_ONCE(tcon->tc_count < 0, "tcon refcount is negative");
spin_unlock(&cifs_tcp_ses_lock);
if (tcon->ses)
server = tcon->ses->server;
cifs_server_dbg(FYI, "tid=0x%x: tcon is closing, skipping async close retry of fid %llu %llu\n",
tcon->tid, persistent_fid, volatile_fid);
return 0;
}
tcon->tc_count++;
spin_unlock(&cifs_tcp_ses_lock);
rc = __smb2_handle_cancelled_cmd(tcon, SMB2_CLOSE_HE, 0,
persistent_fid, volatile_fid);
if (rc)
cifs_put_tcon(tcon);
return rc;
}
int
smb2_handle_cancelled_mid(struct mid_q_entry *mid, struct TCP_Server_Info *server)
{
struct smb2_hdr *hdr = mid->resp_buf;
struct smb2_create_rsp *rsp = mid->resp_buf;
struct cifs_tcon *tcon;
int rc;
if ((mid->optype & CIFS_CP_CREATE_CLOSE_OP) || hdr->Command != SMB2_CREATE ||
hdr->Status != STATUS_SUCCESS)
return 0;
tcon = smb2_find_smb_tcon(server, le64_to_cpu(hdr->SessionId),
le32_to_cpu(hdr->Id.SyncId.TreeId));
if (!tcon)
return -ENOENT;
rc = __smb2_handle_cancelled_cmd(tcon,
le16_to_cpu(hdr->Command),
le64_to_cpu(hdr->MessageId),
rsp->PersistentFileId,
rsp->VolatileFileId);
if (rc)
cifs_put_tcon(tcon);
return rc;
}
/**
* smb311_update_preauth_hash - update @ses hash with the packet data in @iov
*
* Assumes @iov does not contain the rfc1002 length and iov[0] has the
* SMB2 header.
*
* @ses: server session structure
* @server: pointer to server info
* @iov: array containing the SMB request we will send to the server
* @nvec: number of array entries for the iov
*/
int
smb311_update_preauth_hash(struct cifs_ses *ses, struct TCP_Server_Info *server,
struct kvec *iov, int nvec)
{
int i, rc;
struct smb2_hdr *hdr;
struct shash_desc *sha512 = NULL;
hdr = (struct smb2_hdr *)iov[0].iov_base;
/* neg prot are always taken */
if (hdr->Command == SMB2_NEGOTIATE)
goto ok;
/*
* If we process a command which wasn't a negprot it means the
* neg prot was already done, so the server dialect was set
* and we can test it. Preauth requires 3.1.1 for now.
*/
if (server->dialect != SMB311_PROT_ID)
return 0;
if (hdr->Command != SMB2_SESSION_SETUP)
return 0;
/* skip last sess setup response */
if ((hdr->Flags & SMB2_FLAGS_SERVER_TO_REDIR)
&& (hdr->Status == NT_STATUS_OK
|| (hdr->Status !=
cpu_to_le32(NT_STATUS_MORE_PROCESSING_REQUIRED))))
return 0;
ok:
rc = smb311_crypto_shash_allocate(server);
if (rc)
return rc;
sha512 = server->secmech.sha512;
rc = crypto_shash_init(sha512);
if (rc) {
cifs_dbg(VFS, "%s: Could not init sha512 shash\n", __func__);
return rc;
}
rc = crypto_shash_update(sha512, ses->preauth_sha_hash,
SMB2_PREAUTH_HASH_SIZE);
if (rc) {
cifs_dbg(VFS, "%s: Could not update sha512 shash\n", __func__);
return rc;
}
for (i = 0; i < nvec; i++) {
rc = crypto_shash_update(sha512, iov[i].iov_base, iov[i].iov_len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update sha512 shash\n",
__func__);
return rc;
}
}
rc = crypto_shash_final(sha512, ses->preauth_sha_hash);
if (rc) {
cifs_dbg(VFS, "%s: Could not finalize sha512 shash\n",
__func__);
return rc;
}
return 0;
}