diff options
Diffstat (limited to 'source3/smbd/oplock.c')
| -rw-r--r-- | source3/smbd/oplock.c | 1219 |
1 files changed, 1219 insertions, 0 deletions
diff --git a/source3/smbd/oplock.c b/source3/smbd/oplock.c new file mode 100644 index 0000000000..23606f1d14 --- /dev/null +++ b/source3/smbd/oplock.c @@ -0,0 +1,1219 @@ +/* + 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(fd_set *fds, char *buffer, int buffer_len, int timeout) +{ + struct sockaddr_in from; + int fromlen = sizeof(from); + int32 msg_len = 0; + + smb_read_error = 0; + + if(timeout != 0) { + struct timeval to; + int selrtn; + int maxfd = oplock_sock; + + if (koplocks && koplocks->notification_fd != -1) { + FD_SET(koplocks->notification_fd, fds); + maxfd = MAX(maxfd, koplocks->notification_fd); + } + + to.tv_sec = timeout / 1000; + to.tv_usec = (timeout % 1000) * 1000; + + 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); + } + } + + /* 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 = 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 (koplocks) + koplocks->release_oplock(fsp); + + if (fsp->oplock_type == LEVEL_II_OPLOCK) + level_II_oplocks_open--; + else + 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 )); + ret = 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: + + /* 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 level II case. + */ + + if(SVAL(msg_start,OPBRK_MESSAGE_CMD_OFFSET) == 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,OPLOCK_BREAK_CMD | 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(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 )); + } + + if (!local_request && got_lock) + unlock_share_entry_fsp(fsp); + + fsp->oplock_type = NO_OPLOCK; + level_II_oplocks_open--; + + 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) +{ + 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; + + 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)) { + SSVAL(op_break_msg,OPBRK_MESSAGE_CMD_OFFSET,LEVEL_II_OPLOCK_BREAK_CMD); + } else { + SSVAL(op_break_msg,OPBRK_MESSAGE_CMD_OFFSET,OPLOCK_BREAK_CMD); + } + + 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 oplock break message to " ); + 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(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 then + * we are done and may return. + */ + + if (LEVEL_II_OPLOCK_TYPE(share_entry->op_type)) { + DEBUG(3,("request_oplock_break: sent 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; + fd_set fds; + + FD_ZERO(&fds); + FD_SET(oplock_sock,&fds); + + if (koplocks && koplocks->notification_fd != -1) { + FD_SET(koplocks->notification_fd, &fds); + } + + if(receive_local_message(&fds, 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. + */ + if((SVAL(reply_msg_start,OPBRK_MESSAGE_CMD_OFFSET) & CMD_REPLY) && + ((SVAL(reply_msg_start,OPBRK_MESSAGE_CMD_OFFSET) & ~CMD_REPLY) == OPLOCK_BREAK_CMD) && + (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.\n")); + request_oplock_break(share_entry); + } + } + + 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; +} |