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samba-mirror/source3/smbd/oplock.c

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/*
Unix SMB/CIFS implementation.
oplock processing
Copyright (C) Andrew Tridgell 1992-1998
Copyright (C) Jeremy Allison 1998 - 2001
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
/* Oplock ipc UDP socket. */
static int oplock_sock = -1;
uint16 global_oplock_port = 0;
/* Current number of oplocks we have outstanding. */
static int32 exclusive_oplocks_open = 0;
static int32 level_II_oplocks_open = 0;
BOOL global_client_failed_oplock_break = False;
BOOL global_oplock_break = False;
extern int smb_read_error;
static struct kernel_oplocks *koplocks;
static BOOL oplock_break(SMB_DEV_T dev, SMB_INO_T inode, unsigned long file_id, BOOL local);
/****************************************************************************
Get the number of current exclusive oplocks.
****************************************************************************/
int32 get_number_of_exclusive_open_oplocks(void)
{
return exclusive_oplocks_open;
}
/****************************************************************************
Return True if an oplock message is pending.
****************************************************************************/
BOOL oplock_message_waiting(fd_set *fds)
{
if (koplocks && koplocks->msg_waiting(fds))
return True;
if (FD_ISSET(oplock_sock, fds))
return True;
return False;
}
/****************************************************************************
Read an oplock break message from either the oplock UDP fd or the
kernel (if kernel oplocks are supported).
If timeout is zero then *fds contains the file descriptors that
are ready to be read and acted upon. If timeout is non-zero then
*fds contains the file descriptors to be selected on for read.
The timeout is in milliseconds
****************************************************************************/
BOOL receive_local_message( char *buffer, int buffer_len, int timeout)
{
struct sockaddr_in from;
socklen_t fromlen = sizeof(from);
int32 msg_len = 0;
fd_set fds;
int selrtn = -1;
FD_ZERO(&fds);
smb_read_error = 0;
/*
* We need to check for kernel oplocks before going into the select
* here, as the EINTR generated by the linux kernel oplock may have
* already been eaten. JRA.
*/
if (koplocks && koplocks->msg_waiting(&fds)) {
return koplocks->receive_message(&fds, buffer, buffer_len);
}
while (timeout > 0 && selrtn == -1) {
struct timeval to;
int maxfd = oplock_sock;
time_t starttime = time(NULL);
FD_ZERO(&fds);
maxfd = setup_oplock_select_set(&fds);
to.tv_sec = timeout / 1000;
to.tv_usec = (timeout % 1000) * 1000;
DEBUG(5,("receive_local_message: doing select with timeout of %d ms\n", timeout));
selrtn = sys_select(maxfd+1,&fds,NULL,NULL,&to);
if (selrtn == -1 && errno == EINTR) {
/* could be a kernel oplock interrupt */
if (koplocks && koplocks->msg_waiting(&fds)) {
return koplocks->receive_message(&fds, buffer, buffer_len);
}
/*
* Linux 2.0.x seems to have a bug in that
* it can return -1, EINTR with a timeout of zero.
* Make sure we bail out here with a read timeout
* if we got EINTR on a timeout of 1 or less.
*/
if (timeout <= 1) {
smb_read_error = READ_TIMEOUT;
return False;
}
/* Not a kernel interrupt - could be a SIGUSR1 message. We must restart. */
/* We need to decrement the timeout here. */
timeout -= ((time(NULL) - starttime)*1000);
if (timeout < 0)
timeout = 1;
DEBUG(5,("receive_local_message: EINTR : new timeout %d ms\n", timeout));
continue;
}
/* Check if error */
if(selrtn == -1) {
/* something is wrong. Maybe the socket is dead? */
smb_read_error = READ_ERROR;
return False;
}
/* Did we timeout ? */
if (selrtn == 0) {
smb_read_error = READ_TIMEOUT;
return False;
}
}
if (koplocks && koplocks->msg_waiting(&fds)) {
return koplocks->receive_message(&fds, buffer, buffer_len);
}
if (!FD_ISSET(oplock_sock, &fds))
return False;
/*
* From here down we deal with the smbd <--> smbd
* oplock break protocol only.
*/
/*
* Read a loopback udp message.
*/
msg_len = sys_recvfrom(oplock_sock, &buffer[OPBRK_CMD_HEADER_LEN],
buffer_len - OPBRK_CMD_HEADER_LEN, 0, (struct sockaddr *)&from, &fromlen);
if(msg_len < 0) {
DEBUG(0,("receive_local_message. Error in recvfrom. (%s).\n",strerror(errno)));
return False;
}
/* Validate message length. */
if(msg_len > (buffer_len - OPBRK_CMD_HEADER_LEN)) {
DEBUG(0,("receive_local_message: invalid msg_len (%d) max can be %d\n", msg_len,
buffer_len - OPBRK_CMD_HEADER_LEN));
return False;
}
/* Validate message from address (must be localhost). */
if(from.sin_addr.s_addr != htonl(INADDR_LOOPBACK)) {
DEBUG(0,("receive_local_message: invalid 'from' address \
(was %lx should be 127.0.0.1)\n", (long)from.sin_addr.s_addr));
return False;
}
/* Setup the message header */
SIVAL(buffer,OPBRK_CMD_LEN_OFFSET,msg_len);
SSVAL(buffer,OPBRK_CMD_PORT_OFFSET,ntohs(from.sin_port));
return True;
}
/****************************************************************************
Attempt to set an oplock on a file. Always succeeds if kernel oplocks are
disabled (just sets flags). Returns True if oplock set.
****************************************************************************/
BOOL set_file_oplock(files_struct *fsp, int oplock_type)
{
if (koplocks && !koplocks->set_oplock(fsp, oplock_type))
return False;
fsp->oplock_type = oplock_type;
fsp->sent_oplock_break = NO_BREAK_SENT;
if (oplock_type == LEVEL_II_OPLOCK)
level_II_oplocks_open++;
else
exclusive_oplocks_open++;
DEBUG(5,("set_file_oplock: granted oplock on file %s, dev = %x, inode = %.0f, file_id = %lu, \
tv_sec = %x, tv_usec = %x\n",
fsp->fsp_name, (unsigned int)fsp->dev, (double)fsp->inode, fsp->file_id,
(int)fsp->open_time.tv_sec, (int)fsp->open_time.tv_usec ));
return True;
}
/****************************************************************************
Attempt to release an oplock on a file. Decrements oplock count.
****************************************************************************/
void release_file_oplock(files_struct *fsp)
{
if ((fsp->oplock_type != NO_OPLOCK) && koplocks)
koplocks->release_oplock(fsp);
if (fsp->oplock_type == LEVEL_II_OPLOCK)
level_II_oplocks_open--;
else if (fsp->oplock_type)
exclusive_oplocks_open--;
fsp->oplock_type = NO_OPLOCK;
fsp->sent_oplock_break = NO_BREAK_SENT;
flush_write_cache(fsp, OPLOCK_RELEASE_FLUSH);
}
/****************************************************************************
Attempt to downgrade an oplock on a file. Doesn't decrement oplock count.
****************************************************************************/
static void downgrade_file_oplock(files_struct *fsp)
{
if (koplocks)
koplocks->release_oplock(fsp);
fsp->oplock_type = LEVEL_II_OPLOCK;
exclusive_oplocks_open--;
level_II_oplocks_open++;
fsp->sent_oplock_break = NO_BREAK_SENT;
}
/****************************************************************************
Remove a file oplock. Copes with level II and exclusive.
Locks then unlocks the share mode lock. Client can decide to go directly
to none even if a "break-to-level II" was sent.
****************************************************************************/
BOOL remove_oplock(files_struct *fsp, BOOL break_to_none)
{
SMB_DEV_T dev = fsp->dev;
SMB_INO_T inode = fsp->inode;
BOOL ret = True;
/* Remove the oplock flag from the sharemode. */
if (lock_share_entry_fsp(fsp) == False) {
DEBUG(0,("remove_oplock: failed to lock share entry for file %s\n",
fsp->fsp_name ));
return False;
}
if (fsp->sent_oplock_break == EXCLUSIVE_BREAK_SENT || break_to_none) {
/*
* Deal with a reply when a break-to-none was sent.
*/
if(remove_share_oplock(fsp)==False) {
DEBUG(0,("remove_oplock: failed to remove share oplock for file %s fnum %d, \
dev = %x, inode = %.0f\n", fsp->fsp_name, fsp->fnum, (unsigned int)dev, (double)inode));
ret = False;
}
release_file_oplock(fsp);
} else {
/*
* Deal with a reply when a break-to-level II was sent.
*/
if(downgrade_share_oplock(fsp)==False) {
DEBUG(0,("remove_oplock: failed to downgrade share oplock for file %s fnum %d, \
dev = %x, inode = %.0f\n", fsp->fsp_name, fsp->fnum, (unsigned int)dev, (double)inode));
ret = False;
}
downgrade_file_oplock(fsp);
}
unlock_share_entry_fsp(fsp);
return ret;
}
/****************************************************************************
Setup the listening set of file descriptors for an oplock break
message either from the UDP socket or from the kernel. Returns the maximum
fd used.
****************************************************************************/
int setup_oplock_select_set( fd_set *fds)
{
int maxfd = oplock_sock;
if(oplock_sock == -1)
return 0;
FD_SET(oplock_sock,fds);
if (koplocks && koplocks->notification_fd != -1) {
FD_SET(koplocks->notification_fd, fds);
maxfd = MAX(maxfd, koplocks->notification_fd);
}
return maxfd;
}
/****************************************************************************
Process an oplock break message - whether it came from the UDP socket
or from the kernel.
****************************************************************************/
BOOL process_local_message(char *buffer, int buf_size)
{
int32 msg_len;
uint16 from_port;
char *msg_start;
pid_t remotepid;
SMB_DEV_T dev;
SMB_INO_T inode;
unsigned long file_id;
uint16 break_cmd_type;
msg_len = IVAL(buffer,OPBRK_CMD_LEN_OFFSET);
from_port = SVAL(buffer,OPBRK_CMD_PORT_OFFSET);
msg_start = &buffer[OPBRK_CMD_HEADER_LEN];
DEBUG(5,("process_local_message: Got a message of length %d from port (%d)\n",
msg_len, from_port));
/*
* Pull the info out of the requesting packet.
*/
break_cmd_type = SVAL(msg_start,OPBRK_MESSAGE_CMD_OFFSET);
switch(break_cmd_type) {
case KERNEL_OPLOCK_BREAK_CMD:
if (!koplocks) {
DEBUG(0,("unexpected kernel oplock break!\n"));
break;
}
if (!koplocks->parse_message(msg_start, msg_len, &inode, &dev, &file_id)) {
DEBUG(0,("kernel oplock break parse failure!\n"));
}
break;
case OPLOCK_BREAK_CMD:
case LEVEL_II_OPLOCK_BREAK_CMD:
case ASYNC_LEVEL_II_OPLOCK_BREAK_CMD:
/* Ensure that the msg length is correct. */
if(msg_len != OPLOCK_BREAK_MSG_LEN) {
DEBUG(0,("process_local_message: incorrect length for OPLOCK_BREAK_CMD (was %d, should be %d).\n",
(int)msg_len, (int)OPLOCK_BREAK_MSG_LEN));
return False;
}
memcpy((char *)&remotepid, msg_start+OPLOCK_BREAK_PID_OFFSET,sizeof(remotepid));
memcpy((char *)&inode, msg_start+OPLOCK_BREAK_INODE_OFFSET,sizeof(inode));
memcpy((char *)&dev, msg_start+OPLOCK_BREAK_DEV_OFFSET,sizeof(dev));
memcpy((char *)&file_id, msg_start+OPLOCK_BREAK_FILEID_OFFSET,sizeof(file_id));
DEBUG(5,("process_local_message: (%s) oplock break request from \
pid %d, port %d, dev = %x, inode = %.0f, file_id = %lu\n",
(break_cmd_type == OPLOCK_BREAK_CMD) ? "exclusive" : "level II",
(int)remotepid, from_port, (unsigned int)dev, (double)inode, file_id));
break;
/*
* Keep this as a debug case - eventually we can remove it.
*/
case 0x8001:
DEBUG(0,("process_local_message: Received unsolicited break \
reply - dumping info.\n"));
if(msg_len != OPLOCK_BREAK_MSG_LEN) {
DEBUG(0,("process_local_message: ubr: incorrect length for reply \
(was %d, should be %d).\n", (int)msg_len, (int)OPLOCK_BREAK_MSG_LEN));
return False;
}
memcpy((char *)&inode, msg_start+OPLOCK_BREAK_INODE_OFFSET,sizeof(inode));
memcpy((char *)&remotepid, msg_start+OPLOCK_BREAK_PID_OFFSET,sizeof(remotepid));
memcpy((char *)&dev, msg_start+OPLOCK_BREAK_DEV_OFFSET,sizeof(dev));
memcpy((char *)&file_id, msg_start+OPLOCK_BREAK_FILEID_OFFSET,sizeof(file_id));
DEBUG(0,("process_local_message: unsolicited oplock break reply from \
pid %d, port %d, dev = %x, inode = %.0f, file_id = %lu\n",
(int)remotepid, from_port, (unsigned int)dev, (double)inode, file_id));
return False;
default:
DEBUG(0,("process_local_message: unknown UDP message command code (%x) - ignoring.\n",
(unsigned int)SVAL(msg_start,0)));
return False;
}
/*
* Now actually process the break request.
*/
if((exclusive_oplocks_open + level_II_oplocks_open) != 0) {
if (oplock_break(dev, inode, file_id, False) == False) {
DEBUG(0,("process_local_message: oplock break failed.\n"));
return False;
}
} else {
/*
* If we have no record of any currently open oplocks,
* it's not an error, as a close command may have
* just been issued on the file that was oplocked.
* Just log a message and return success in this case.
*/
DEBUG(3,("process_local_message: oplock break requested with no outstanding \
oplocks. Returning success.\n"));
}
/*
* Do the appropriate reply - none in the kernel or async level II case.
*/
if(break_cmd_type == OPLOCK_BREAK_CMD || break_cmd_type == LEVEL_II_OPLOCK_BREAK_CMD) {
struct sockaddr_in toaddr;
/* Send the message back after OR'ing in the 'REPLY' bit. */
SSVAL(msg_start,OPBRK_MESSAGE_CMD_OFFSET,break_cmd_type | CMD_REPLY);
memset((char *)&toaddr,'\0',sizeof(toaddr));
toaddr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
toaddr.sin_port = htons(from_port);
toaddr.sin_family = AF_INET;
if(sys_sendto( oplock_sock, msg_start, OPLOCK_BREAK_MSG_LEN, 0,
(struct sockaddr *)&toaddr, sizeof(toaddr)) < 0) {
DEBUG(0,("process_local_message: sendto process %d failed. Errno was %s\n",
(int)remotepid, strerror(errno)));
return False;
}
DEBUG(5,("process_local_message: oplock break reply sent to \
pid %d, port %d, for file dev = %x, inode = %.0f, file_id = %lu\n",
(int)remotepid, from_port, (unsigned int)dev, (double)inode, file_id));
}
return True;
}
/****************************************************************************
Set up an oplock break message.
****************************************************************************/
static void prepare_break_message(char *outbuf, files_struct *fsp, BOOL level2)
{
memset(outbuf,'\0',smb_size);
set_message(outbuf,8,0,True);
SCVAL(outbuf,smb_com,SMBlockingX);
SSVAL(outbuf,smb_tid,fsp->conn->cnum);
SSVAL(outbuf,smb_pid,0xFFFF);
SSVAL(outbuf,smb_uid,0);
SSVAL(outbuf,smb_mid,0xFFFF);
SCVAL(outbuf,smb_vwv0,0xFF);
SSVAL(outbuf,smb_vwv2,fsp->fnum);
SCVAL(outbuf,smb_vwv3,LOCKING_ANDX_OPLOCK_RELEASE);
SCVAL(outbuf,smb_vwv3+1,level2 ? OPLOCKLEVEL_II : OPLOCKLEVEL_NONE);
}
/****************************************************************************
Function to do the waiting before sending a local break.
****************************************************************************/
static void wait_before_sending_break(BOOL local_request)
{
extern struct timeval smb_last_time;
if(local_request) {
struct timeval cur_tv;
long wait_left = (long)lp_oplock_break_wait_time();
if (wait_left == 0)
return;
GetTimeOfDay(&cur_tv);
wait_left -= ((cur_tv.tv_sec - smb_last_time.tv_sec)*1000) +
((cur_tv.tv_usec - smb_last_time.tv_usec)/1000);
if(wait_left > 0) {
wait_left = MIN(wait_left, 1000);
sys_usleep(wait_left * 1000);
}
}
}
/****************************************************************************
Ensure that we have a valid oplock.
****************************************************************************/
static files_struct *initial_break_processing(SMB_DEV_T dev, SMB_INO_T inode, unsigned long file_id)
{
files_struct *fsp = NULL;
if( DEBUGLVL( 3 ) ) {
dbgtext( "initial_break_processing: called for dev = %x, inode = %.0f file_id = %lu\n",
(unsigned int)dev, (double)inode, file_id);
dbgtext( "Current oplocks_open (exclusive = %d, levelII = %d)\n",
exclusive_oplocks_open, level_II_oplocks_open );
}
/*
* We need to search the file open table for the
* entry containing this dev and inode, and ensure
* we have an oplock on it.
*/
fsp = file_find_dif(dev, inode, file_id);
if(fsp == NULL) {
/* The file could have been closed in the meantime - return success. */
if( DEBUGLVL( 3 ) ) {
dbgtext( "initial_break_processing: cannot find open file with " );
dbgtext( "dev = %x, inode = %.0f file_id = %lu", (unsigned int)dev,
(double)inode, file_id);
dbgtext( "allowing break to succeed.\n" );
}
return NULL;
}
/* Ensure we have an oplock on the file */
/*
* There is a potential race condition in that an oplock could
* have been broken due to another udp request, and yet there are
* still oplock break messages being sent in the udp message
* queue for this file. So return true if we don't have an oplock,
* as we may have just freed it.
*/
if(fsp->oplock_type == NO_OPLOCK) {
if( DEBUGLVL( 3 ) ) {
dbgtext( "initial_break_processing: file %s ", fsp->fsp_name );
dbgtext( "(dev = %x, inode = %.0f, file_id = %lu) has no oplock.\n",
(unsigned int)dev, (double)inode, fsp->file_id );
dbgtext( "Allowing break to succeed regardless.\n" );
}
return NULL;
}
return fsp;
}
/****************************************************************************
Process a level II oplock break directly.
****************************************************************************/
BOOL oplock_break_level2(files_struct *fsp, BOOL local_request, int token)
{
extern uint32 global_client_caps;
char outbuf[128];
BOOL got_lock = False;
SMB_DEV_T dev = fsp->dev;
SMB_INO_T inode = fsp->inode;
/*
* We can have a level II oplock even if the client is not
* level II oplock aware. In this case just remove the
* flags and don't send the break-to-none message to
* the client.
*/
if (global_client_caps & CAP_LEVEL_II_OPLOCKS) {
/*
* If we are sending an oplock break due to an SMB sent
* by our own client we ensure that we wait at leat
* lp_oplock_break_wait_time() milliseconds before sending
* the packet. Sending the packet sooner can break Win9x
* and has reported to cause problems on NT. JRA.
*/
wait_before_sending_break(local_request);
/* Prepare the SMBlockingX message. */
prepare_break_message( outbuf, fsp, False);
if (!send_smb(smbd_server_fd(), outbuf))
exit_server("oplock_break_level2: send_smb failed.");
}
/*
* Now we must update the shared memory structure to tell
* everyone else we no longer have a level II oplock on
* this open file. If local_request is true then token is
* the existing lock on the shared memory area.
*/
if(!local_request && lock_share_entry_fsp(fsp) == False) {
DEBUG(0,("oplock_break_level2: unable to lock share entry for file %s\n", fsp->fsp_name ));
} else {
got_lock = True;
}
if(remove_share_oplock(fsp)==False) {
DEBUG(0,("oplock_break_level2: unable to remove level II oplock for file %s\n", fsp->fsp_name ));
}
release_file_oplock(fsp);
if (!local_request && got_lock)
unlock_share_entry_fsp(fsp);
if(level_II_oplocks_open < 0) {
DEBUG(0,("oplock_break_level2: level_II_oplocks_open < 0 (%d). PANIC ERROR\n",
level_II_oplocks_open));
abort();
}
if( DEBUGLVL( 3 ) ) {
dbgtext( "oplock_break_level2: returning success for " );
dbgtext( "dev = %x, inode = %.0f, file_id = %lu\n", (unsigned int)dev, (double)inode, fsp->file_id );
dbgtext( "Current level II oplocks_open = %d\n", level_II_oplocks_open );
}
return True;
}
/****************************************************************************
Process an oplock break directly.
****************************************************************************/
static BOOL oplock_break(SMB_DEV_T dev, SMB_INO_T inode, unsigned long file_id, BOOL local_request)
{
extern uint32 global_client_caps;
extern struct current_user current_user;
char *inbuf = NULL;
char *outbuf = NULL;
files_struct *fsp = NULL;
time_t start_time;
BOOL shutdown_server = False;
BOOL oplock_timeout = False;
connection_struct *saved_user_conn;
connection_struct *saved_fsp_conn;
int saved_vuid;
pstring saved_dir;
int timeout = (OPLOCK_BREAK_TIMEOUT * 1000);
pstring file_name;
BOOL using_levelII;
if((fsp = initial_break_processing(dev, inode, file_id)) == NULL)
return True;
/*
* Deal with a level II oplock going break to none separately.
*/
if (LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
return oplock_break_level2(fsp, local_request, -1);
/* Mark the oplock break as sent - we don't want to send twice! */
if (fsp->sent_oplock_break) {
if( DEBUGLVL( 0 ) ) {
dbgtext( "oplock_break: ERROR: oplock_break already sent for " );
dbgtext( "file %s ", fsp->fsp_name);
dbgtext( "(dev = %x, inode = %.0f, file_id = %lu)\n", (unsigned int)dev, (double)inode, fsp->file_id );
}
/*
* We have to fail the open here as we cannot send another oplock break on
* this file whilst we are awaiting a response from the client - neither
* can we allow another open to succeed while we are waiting for the client.
*/
return False;
}
if(global_oplock_break) {
DEBUG(0,("ABORT : ABORT : recursion in oplock_break !!!!!\n"));
abort();
}
/*
* Now comes the horrid part. We must send an oplock break to the client,
* and then process incoming messages until we get a close or oplock release.
* At this point we know we need a new inbuf/outbuf buffer pair.
* We cannot use these staticaly as we may recurse into here due to
* messages crossing on the wire.
*/
if((inbuf = (char *)malloc(BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE + SAFETY_MARGIN))==NULL) {
DEBUG(0,("oplock_break: malloc fail for input buffer.\n"));
return False;
}
if((outbuf = (char *)malloc(BUFFER_SIZE + LARGE_WRITEX_HDR_SIZE + SAFETY_MARGIN))==NULL) {
DEBUG(0,("oplock_break: malloc fail for output buffer.\n"));
SAFE_FREE(inbuf);
return False;
}
/*
* If we are sending an oplock break due to an SMB sent
* by our own client we ensure that we wait at leat
* lp_oplock_break_wait_time() milliseconds before sending
* the packet. Sending the packet sooner can break Win9x
* and has reported to cause problems on NT. JRA.
*/
wait_before_sending_break(local_request);
/* Prepare the SMBlockingX message. */
if ((global_client_caps & CAP_LEVEL_II_OPLOCKS) &&
!koplocks && /* NOTE: we force levelII off for kernel oplocks - this will change when it is supported */
lp_level2_oplocks(SNUM(fsp->conn))) {
using_levelII = True;
} else {
using_levelII = False;
}
prepare_break_message( outbuf, fsp, using_levelII);
/* Remember if we just sent a break to level II on this file. */
fsp->sent_oplock_break = using_levelII? LEVEL_II_BREAK_SENT:EXCLUSIVE_BREAK_SENT;
if (!send_smb(smbd_server_fd(), outbuf))
exit_server("oplock_break: send_smb failed.");
/* We need this in case a readraw crosses on the wire. */
global_oplock_break = True;
/* Process incoming messages. */
/*
* JRA - If we don't get a break from the client in OPLOCK_BREAK_TIMEOUT
* seconds we should just die....
*/
start_time = time(NULL);
/*
* Save the information we need to re-become the
* user, then unbecome the user whilst we're doing this.
*/
saved_user_conn = current_user.conn;
saved_vuid = current_user.vuid;
saved_fsp_conn = fsp->conn;
change_to_root_user();
vfs_GetWd(saved_fsp_conn,saved_dir);
/* Save the chain fnum. */
file_chain_save();
/*
* From Charles Hoch <hoch@exemplary.com>. If the break processing
* code closes the file (as it often does), then the fsp pointer here
* points to free()'d memory. We *must* revalidate fsp each time
* around the loop.
*/
pstrcpy(file_name, fsp->fsp_name);
while((fsp = initial_break_processing(dev, inode, file_id)) &&
OPEN_FSP(fsp) && EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
if(receive_smb(smbd_server_fd(),inbuf, timeout) == False) {
/*
* Die if we got an error.
*/
if (smb_read_error == READ_EOF) {
DEBUG( 0, ( "oplock_break: end of file from client\n" ) );
shutdown_server = True;
} else if (smb_read_error == READ_ERROR) {
DEBUG( 0, ("oplock_break: receive_smb error (%s)\n", strerror(errno)) );
shutdown_server = True;
} else if (smb_read_error == READ_TIMEOUT) {
DEBUG( 0, ( "oplock_break: receive_smb timed out after %d seconds.\n", OPLOCK_BREAK_TIMEOUT ) );
oplock_timeout = True;
}
DEBUGADD( 0, ( "oplock_break failed for file %s ", file_name ) );
DEBUGADD( 0, ( "(dev = %x, inode = %.0f, file_id = %lu).\n",
(unsigned int)dev, (double)inode, file_id));
break;
}
/*
* There are certain SMB requests that we shouldn't allow
* to recurse. opens, renames and deletes are the obvious
* ones. This is handled in the switch_message() function.
* If global_oplock_break is set they will push the packet onto
* the pending smb queue and return -1 (no reply).
* JRA.
*/
process_smb(inbuf, outbuf);
/*
* Die if we go over the time limit.
*/
if((time(NULL) - start_time) > OPLOCK_BREAK_TIMEOUT) {
if( DEBUGLVL( 0 ) ) {
dbgtext( "oplock_break: no break received from client " );
dbgtext( "within %d seconds.\n", OPLOCK_BREAK_TIMEOUT );
dbgtext( "oplock_break failed for file %s ", fsp->fsp_name );
dbgtext( "(dev = %x, inode = %.0f, file_id = %lu).\n",
(unsigned int)dev, (double)inode, file_id );
}
oplock_timeout = True;
break;
}
}
/*
* Go back to being the user who requested the oplock
* break.
*/
if((saved_user_conn != NULL) && (saved_vuid != UID_FIELD_INVALID) && !change_to_user(saved_user_conn, saved_vuid)) {
DEBUG( 0, ( "oplock_break: unable to re-become user!" ) );
DEBUGADD( 0, ( "Shutting down server\n" ) );
close(oplock_sock);
exit_server("unable to re-become user");
}
/* Including the directory. */
vfs_ChDir(saved_fsp_conn,saved_dir);
/* Restore the chain fnum. */
file_chain_restore();
/* Free the buffers we've been using to recurse. */
SAFE_FREE(inbuf);
SAFE_FREE(outbuf);
/* We need this in case a readraw crossed on the wire. */
if(global_oplock_break)
global_oplock_break = False;
/*
* If the client timed out then clear the oplock (or go to level II)
* and continue. This seems to be what NT does and is better than dropping
* the connection.
*/
if(oplock_timeout && (fsp = initial_break_processing(dev, inode, file_id)) &&
OPEN_FSP(fsp) && EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type)) {
DEBUG(0,("oplock_break: client failure in oplock break in file %s\n", fsp->fsp_name));
remove_oplock(fsp,True);
#if FASCIST_OPLOCK_BACKOFF
global_client_failed_oplock_break = True; /* Never grant this client an oplock again. */
#endif
}
/*
* If the client had an error we must die.
*/
if(shutdown_server) {
DEBUG( 0, ( "oplock_break: client failure in break - " ) );
DEBUGADD( 0, ( "shutting down this smbd.\n" ) );
close(oplock_sock);
exit_server("oplock break failure");
}
/* Santity check - remove this later. JRA */
if(exclusive_oplocks_open < 0) {
DEBUG(0,("oplock_break: exclusive_oplocks_open < 0 (%d). PANIC ERROR\n", exclusive_oplocks_open));
abort();
}
if( DEBUGLVL( 3 ) ) {
dbgtext( "oplock_break: returning success for " );
dbgtext( "dev = %x, inode = %.0f, file_id = %lu\n", (unsigned int)dev, (double)inode, file_id );
dbgtext( "Current exclusive_oplocks_open = %d\n", exclusive_oplocks_open );
}
return True;
}
/****************************************************************************
Send an oplock break message to another smbd process. If the oplock is held
by the local smbd then call the oplock break function directly.
****************************************************************************/
BOOL request_oplock_break(share_mode_entry *share_entry, BOOL async)
{
char op_break_msg[OPLOCK_BREAK_MSG_LEN];
struct sockaddr_in addr_out;
pid_t pid = sys_getpid();
time_t start_time;
int time_left;
SMB_DEV_T dev = share_entry->dev;
SMB_INO_T inode = share_entry->inode;
unsigned long file_id = share_entry->share_file_id;
uint16 break_cmd_type;
if(pid == share_entry->pid) {
/* We are breaking our own oplock, make sure it's us. */
if(share_entry->op_port != global_oplock_port) {
DEBUG(0,("request_oplock_break: corrupt share mode entry - pid = %d, port = %d \
should be %d\n", (int)pid, share_entry->op_port, global_oplock_port));
return False;
}
DEBUG(5,("request_oplock_break: breaking our own oplock\n"));
#if 1 /* JRA PARANOIA TEST.... */
{
files_struct *fsp = file_find_dif(dev, inode, file_id);
if (!fsp) {
DEBUG(0,("request_oplock_break: PANIC : breaking our own oplock requested for \
dev = %x, inode = %.0f, file_id = %lu and no fsp found !\n",
(unsigned int)dev, (double)inode, file_id ));
smb_panic("request_oplock_break: no fsp found for our own oplock\n");
}
}
#endif /* END JRA PARANOIA TEST... */
/* Call oplock break direct. */
return oplock_break(dev, inode, file_id, True);
}
/* We need to send a OPLOCK_BREAK_CMD message to the port in the share mode entry. */
if (LEVEL_II_OPLOCK_TYPE(share_entry->op_type)) {
break_cmd_type = async ? ASYNC_LEVEL_II_OPLOCK_BREAK_CMD : LEVEL_II_OPLOCK_BREAK_CMD;
} else {
break_cmd_type = OPLOCK_BREAK_CMD;
}
SSVAL(op_break_msg,OPBRK_MESSAGE_CMD_OFFSET,break_cmd_type);
memcpy(op_break_msg+OPLOCK_BREAK_PID_OFFSET,(char *)&pid,sizeof(pid));
memcpy(op_break_msg+OPLOCK_BREAK_DEV_OFFSET,(char *)&dev,sizeof(dev));
memcpy(op_break_msg+OPLOCK_BREAK_INODE_OFFSET,(char *)&inode,sizeof(inode));
memcpy(op_break_msg+OPLOCK_BREAK_FILEID_OFFSET,(char *)&file_id,sizeof(file_id));
/* Set the address and port. */
memset((char *)&addr_out,'\0',sizeof(addr_out));
addr_out.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
addr_out.sin_port = htons( share_entry->op_port );
addr_out.sin_family = AF_INET;
if( DEBUGLVL( 3 ) ) {
dbgtext( "request_oplock_break: sending a %s oplock break message to ", async ? "asynchronous" : "synchronous" );
dbgtext( "pid %d on port %d ", (int)share_entry->pid, share_entry->op_port );
dbgtext( "for dev = %x, inode = %.0f, file_id = %lu\n",
(unsigned int)dev, (double)inode, file_id );
}
if(sys_sendto(oplock_sock,op_break_msg,OPLOCK_BREAK_MSG_LEN,0,
(struct sockaddr *)&addr_out,sizeof(addr_out)) < 0) {
if( DEBUGLVL( 0 ) ) {
dbgtext( "request_oplock_break: failed when sending a oplock " );
dbgtext( "break message to pid %d ", (int)share_entry->pid );
dbgtext( "on port %d ", share_entry->op_port );
dbgtext( "for dev = %x, inode = %.0f, file_id = %lu\n",
(unsigned int)dev, (double)inode, file_id );
dbgtext( "Error was %s\n", strerror(errno) );
}
return False;
}
/*
* If we just sent a message to a level II oplock share entry in async mode then
* we are done and may return.
*/
if (LEVEL_II_OPLOCK_TYPE(share_entry->op_type) && async) {
DEBUG(3,("request_oplock_break: sent async break message to level II entry.\n"));
return True;
}
/*
* Now we must await the oplock broken message coming back
* from the target smbd process. Timeout if it fails to
* return in (OPLOCK_BREAK_TIMEOUT + OPLOCK_BREAK_TIMEOUT_FUDGEFACTOR) seconds.
* While we get messages that aren't ours, loop.
*/
start_time = time(NULL);
time_left = OPLOCK_BREAK_TIMEOUT+OPLOCK_BREAK_TIMEOUT_FUDGEFACTOR;
while(time_left >= 0) {
char op_break_reply[OPBRK_CMD_HEADER_LEN+OPLOCK_BREAK_MSG_LEN];
uint16 reply_from_port;
char *reply_msg_start;
if(receive_local_message(op_break_reply, sizeof(op_break_reply),
time_left ? time_left * 1000 : 1) == False) {
if(smb_read_error == READ_TIMEOUT) {
if( DEBUGLVL( 0 ) ) {
dbgtext( "request_oplock_break: no response received to oplock " );
dbgtext( "break request to pid %d ", (int)share_entry->pid );
dbgtext( "on port %d ", share_entry->op_port );
dbgtext( "for dev = %x, inode = %.0f, file_id = %lu\n",
(unsigned int)dev, (double)inode, file_id );
}
/*
* This is a hack to make handling of failing clients more robust.
* If a oplock break response message is not received in the timeout
* period we may assume that the smbd servicing that client holding
* the oplock has died and the client changes were lost anyway, so
* we should continue to try and open the file.
*/
break;
} else {
if( DEBUGLVL( 0 ) ) {
dbgtext( "request_oplock_break: error in response received " );
dbgtext( "to oplock break request to pid %d ", (int)share_entry->pid );
dbgtext( "on port %d ", share_entry->op_port );
dbgtext( "for dev = %x, inode = %.0f, file_id = %lu\n",
(unsigned int)dev, (double)inode, file_id );
dbgtext( "Error was (%s).\n", strerror(errno) );
}
}
return False;
}
reply_from_port = SVAL(op_break_reply,OPBRK_CMD_PORT_OFFSET);
reply_msg_start = &op_break_reply[OPBRK_CMD_HEADER_LEN];
/*
* Test to see if this is the reply we are awaiting (ie. the one we sent with the CMD_REPLY flag OR'ed in).
*/
if((SVAL(reply_msg_start,OPBRK_MESSAGE_CMD_OFFSET) & CMD_REPLY) &&
((SVAL(reply_msg_start,OPBRK_MESSAGE_CMD_OFFSET) & ~CMD_REPLY) == break_cmd_type) &&
(reply_from_port == share_entry->op_port) &&
(memcmp(&reply_msg_start[OPLOCK_BREAK_PID_OFFSET], &op_break_msg[OPLOCK_BREAK_PID_OFFSET],
OPLOCK_BREAK_MSG_LEN - OPLOCK_BREAK_PID_OFFSET) == 0)) {
/*
* This is the reply we've been waiting for.
*/
break;
} else {
/*
* This is another message - a break request.
* Note that both kernel oplock break requests
* and UDP inter-smbd oplock break requests will
* be processed here.
*
* Process it to prevent potential deadlock.
* Note that the code in switch_message() prevents
* us from recursing into here as any SMB requests
* we might process that would cause another oplock
* break request to be made will be queued.
* JRA.
*/
process_local_message(op_break_reply, sizeof(op_break_reply));
}
time_left -= (time(NULL) - start_time);
}
DEBUG(3,("request_oplock_break: broke oplock.\n"));
return True;
}
/****************************************************************************
Attempt to break an oplock on a file (if oplocked).
Returns True if the file was closed as a result of
the oplock break, False otherwise.
Used as a last ditch attempt to free a space in the
file table when we have run out.
****************************************************************************/
BOOL attempt_close_oplocked_file(files_struct *fsp)
{
DEBUG(5,("attempt_close_oplocked_file: checking file %s.\n", fsp->fsp_name));
if (EXCLUSIVE_OPLOCK_TYPE(fsp->oplock_type) && !fsp->sent_oplock_break && (fsp->fd != -1)) {
/* Try and break the oplock. */
if (oplock_break(fsp->dev, fsp->inode, fsp->file_id, True)) {
if(file_find_fsp(fsp) == NULL) /* Did the oplock break close the file ? */
return True;
}
}
return False;
}
/****************************************************************************
This function is called on any file modification or lock request. If a file
is level 2 oplocked then it must tell all other level 2 holders to break to none.
****************************************************************************/
void release_level_2_oplocks_on_change(files_struct *fsp)
{
share_mode_entry *share_list = NULL;
pid_t pid = sys_getpid();
int token = -1;
int num_share_modes = 0;
int i;
/*
* If this file is level II oplocked then we need
* to grab the shared memory lock and inform all
* other files with a level II lock that they need
* to flush their read caches. We keep the lock over
* the shared memory area whilst doing this.
*/
if (!LEVEL_II_OPLOCK_TYPE(fsp->oplock_type))
return;
if (lock_share_entry_fsp(fsp) == False) {
DEBUG(0,("release_level_2_oplocks_on_change: failed to lock share mode entry for file %s.\n", fsp->fsp_name ));
}
num_share_modes = get_share_modes(fsp->conn, fsp->dev, fsp->inode, &share_list);
DEBUG(10,("release_level_2_oplocks_on_change: num_share_modes = %d\n",
num_share_modes ));
for(i = 0; i < num_share_modes; i++) {
share_mode_entry *share_entry = &share_list[i];
/*
* As there could have been multiple writes waiting at the lock_share_entry
* gate we may not be the first to enter. Hence the state of the op_types
* in the share mode entries may be partly NO_OPLOCK and partly LEVEL_II
* oplock. It will do no harm to re-send break messages to those smbd's
* that are still waiting their turn to remove their LEVEL_II state, and
* also no harm to ignore existing NO_OPLOCK states. JRA.
*/
DEBUG(10,("release_level_2_oplocks_on_change: share_entry[%i]->op_type == %d\n",
i, share_entry->op_type ));
if (share_entry->op_type == NO_OPLOCK)
continue;
/* Paranoia .... */
if (EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) {
DEBUG(0,("release_level_2_oplocks_on_change: PANIC. share mode entry %d is an exlusive oplock !\n", i ));
unlock_share_entry(fsp->conn, fsp->dev, fsp->inode);
abort();
}
/*
* Check if this is a file we have open (including the
* file we've been called to do write_file on. If so
* then break it directly without releasing the lock.
*/
if (pid == share_entry->pid) {
files_struct *new_fsp = file_find_dif(share_entry->dev, share_entry->inode, share_entry->share_file_id);
/* Paranoia check... */
if(new_fsp == NULL) {
DEBUG(0,("release_level_2_oplocks_on_change: PANIC. share mode entry %d is not a local file !\n", i ));
unlock_share_entry(fsp->conn, fsp->dev, fsp->inode);
abort();
}
DEBUG(10,("release_level_2_oplocks_on_change: breaking our own oplock.\n"));
oplock_break_level2(new_fsp, True, token);
} else {
/*
* This is a remote file and so we send an asynchronous
* message.
*/
DEBUG(10,("release_level_2_oplocks_on_change: breaking remote oplock (async).\n"));
request_oplock_break(share_entry, True);
}
}
SAFE_FREE(share_list);
unlock_share_entry_fsp(fsp);
/* Paranoia check... */
if (LEVEL_II_OPLOCK_TYPE(fsp->oplock_type)) {
DEBUG(0,("release_level_2_oplocks_on_change: PANIC. File %s still has a level II oplock.\n", fsp->fsp_name));
smb_panic("release_level_2_oplocks_on_change");
}
}
/****************************************************************************
setup oplocks for this process
****************************************************************************/
BOOL init_oplocks(void)
{
struct sockaddr_in sock_name;
socklen_t len = sizeof(sock_name);
DEBUG(3,("open_oplock_ipc: opening loopback UDP socket.\n"));
/* Open a lookback UDP socket on a random port. */
oplock_sock = open_socket_in(SOCK_DGRAM, 0, 0, htonl(INADDR_LOOPBACK),False);
if (oplock_sock == -1) {
DEBUG(0,("open_oplock_ipc: Failed to get local UDP socket for \
address %lx. Error was %s\n", (long)htonl(INADDR_LOOPBACK), strerror(errno)));
global_oplock_port = 0;
return(False);
}
/* Find out the transient UDP port we have been allocated. */
if(getsockname(oplock_sock, (struct sockaddr *)&sock_name, &len)<0) {
DEBUG(0,("open_oplock_ipc: Failed to get local UDP port. Error was %s\n",
strerror(errno)));
close(oplock_sock);
oplock_sock = -1;
global_oplock_port = 0;
return False;
}
global_oplock_port = ntohs(sock_name.sin_port);
if (lp_kernel_oplocks()) {
#if HAVE_KERNEL_OPLOCKS_IRIX
koplocks = irix_init_kernel_oplocks();
#elif HAVE_KERNEL_OPLOCKS_LINUX
koplocks = linux_init_kernel_oplocks();
#endif
}
DEBUG(3,("open_oplock ipc: pid = %d, global_oplock_port = %u\n",
(int)sys_getpid(), global_oplock_port));
return True;
}