r6172: Tidy up error processing significantly. Remove unix_ERR_XXX global nastyness.

[sfrench/samba-autobuild/.git] / source / smbd / open.c

/* 
   Unix SMB/CIFS implementation.
   file opening and share modes
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Jeremy Allison 2001-2004
   
   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"

extern userdom_struct current_user_info;
extern uint16 global_oplock_port;
extern uint16 global_smbpid;
extern BOOL global_client_failed_oplock_break;

struct dev_inode_bundle {
        SMB_DEV_T dev;
        SMB_INO_T inode;
};

/****************************************************************************
 fd support routines - attempt to do a dos_open.
****************************************************************************/

static int fd_open(struct connection_struct *conn, const char *fname, 
                   int flags, mode_t mode)
{
        int fd;
#ifdef O_NOFOLLOW
        if (!lp_symlinks(SNUM(conn)))
                flags |= O_NOFOLLOW;
#endif

        fd = SMB_VFS_OPEN(conn,fname,flags,mode);

        DEBUG(10,("fd_open: name %s, flags = 0%o mode = 0%o, fd = %d. %s\n", fname,
                flags, (int)mode, fd, (fd == -1) ? strerror(errno) : "" ));

        return fd;
}

/****************************************************************************
 Close the file associated with a fsp.
****************************************************************************/

int fd_close(struct connection_struct *conn, files_struct *fsp)
{
        if (fsp->fd == -1)
                return 0; /* what we used to call a stat open. */
        return fd_close_posix(conn, fsp);
}


/****************************************************************************
 Check a filename for the pipe string.
****************************************************************************/

static void check_for_pipe(const char *fname)
{
        /* special case of pipe opens */
        char s[10];
        StrnCpy(s,fname,sizeof(s)-1);
        strlower_m(s);
        if (strstr(s,"pipe/")) {
                DEBUG(3,("Rejecting named pipe open for %s\n",fname));
                set_saved_error_triple(ERRSRV, ERRaccess, NT_STATUS_ACCESS_DENIED);
        }
}

/****************************************************************************
 Change the ownership of a file to that of the parent directory.
 Do this by fd if possible.
****************************************************************************/

void change_owner_to_parent(connection_struct *conn, files_struct *fsp, const char *fname, SMB_STRUCT_STAT *psbuf)
{
        const char *parent_path = parent_dirname(fname);
        SMB_STRUCT_STAT parent_st;
        int ret;

        ret = SMB_VFS_STAT(conn, parent_path, &parent_st);
        if (ret == -1) {
                DEBUG(0,("change_owner_to_parent: failed to stat parent directory %s. Error was %s\n",
                        parent_path, strerror(errno) ));
                return;
        }

        if (fsp && fsp->fd != -1) {
                become_root();
                ret = SMB_VFS_FCHOWN(fsp, fsp->fd, parent_st.st_uid, (gid_t)-1);
                unbecome_root();
                if (ret == -1) {
                        DEBUG(0,("change_owner_to_parent: failed to fchown file %s to parent directory uid %u. \
Error was %s\n",
                                fname, (unsigned int)parent_st.st_uid, strerror(errno) ));
                }

                DEBUG(10,("change_owner_to_parent: changed new file %s to parent directory uid %u.\n",
                        fname, (unsigned int)parent_st.st_uid ));

        } else {
                /* We've already done an lstat into psbuf, and we know it's a directory. If
                   we can cd into the directory and the dev/ino are the same then we can safely
                   chown without races as we're locking the directory in place by being in it.
                   This should work on any UNIX (thanks tridge :-). JRA.
                */

                pstring saved_dir;
                SMB_STRUCT_STAT sbuf;

                if (!vfs_GetWd(conn,saved_dir)) {
                        DEBUG(0,("change_owner_to_parent: failed to get current working directory\n"));
                        return;
                }

                /* Chdir into the new path. */
                if (vfs_ChDir(conn, fname) == -1) {
                        DEBUG(0,("change_owner_to_parent: failed to change current working directory to %s. \
Error was %s\n", fname, strerror(errno) ));
                        goto out;
                }

                if (SMB_VFS_STAT(conn,".",&sbuf) == -1) {
                        DEBUG(0,("change_owner_to_parent: failed to stat directory '.' (%s) \
Error was %s\n", fname, strerror(errno)));
                        goto out;
                }

                /* Ensure we're pointing at the same place. */
                if (sbuf.st_dev != psbuf->st_dev || sbuf.st_ino != psbuf->st_ino || sbuf.st_mode != psbuf->st_mode ) {
                        DEBUG(0,("change_owner_to_parent: device/inode/mode on directory %s changed. Refusing to chown !\n",
                                fname ));
                        goto out;
                }

                become_root();
                ret = SMB_VFS_CHOWN(conn, ".", parent_st.st_uid, (gid_t)-1);
                unbecome_root();
                if (ret == -1) {
                        DEBUG(10,("change_owner_to_parent: failed to chown directory %s to parent directory uid %u. \
Error was %s\n",
                                fname, (unsigned int)parent_st.st_uid, strerror(errno) ));
                        goto out;
                }

                DEBUG(10,("change_owner_to_parent: changed ownership of new directory %s to parent directory uid %u.\n",
                        fname, (unsigned int)parent_st.st_uid ));

  out:

                vfs_ChDir(conn,saved_dir);
        }
}

/****************************************************************************
 Open a file.
****************************************************************************/

static BOOL open_file(files_struct *fsp,connection_struct *conn,
                      const char *fname,SMB_STRUCT_STAT *psbuf,int flags,mode_t mode, uint32 desired_access)
{
        extern struct current_user current_user;
        int accmode = (flags & O_ACCMODE);
        int local_flags = flags;

        fsp->fd = -1;
        fsp->oplock_type = NO_OPLOCK;
        errno = EPERM;

        /* Check permissions */

        /*
         * This code was changed after seeing a client open request 
         * containing the open mode of (DENY_WRITE/read-only) with
         * the 'create if not exist' bit set. The previous code
         * would fail to open the file read only on a read-only share
         * as it was checking the flags parameter  directly against O_RDONLY,
         * this was failing as the flags parameter was set to O_RDONLY|O_CREAT.
         * JRA.
         */

        if (!CAN_WRITE(conn)) {
                /* It's a read-only share - fail if we wanted to write. */
                if(accmode != O_RDONLY) {
                        DEBUG(3,("Permission denied opening %s\n",fname));
                        check_for_pipe(fname);
                        return False;
                } else if(flags & O_CREAT) {
                        /* We don't want to write - but we must make sure that O_CREAT
                           doesn't create the file if we have write access into the
                           directory.
                        */
                        flags &= ~O_CREAT;
                        local_flags &= ~O_CREAT;
                }
        }

        /*
         * This little piece of insanity is inspired by the
         * fact that an NT client can open a file for O_RDONLY,
         * but set the create disposition to FILE_EXISTS_TRUNCATE.
         * If the client *can* write to the file, then it expects to
         * truncate the file, even though it is opening for readonly.
         * Quicken uses this stupid trick in backup file creation...
         * Thanks *greatly* to "David W. Chapman Jr." <dwcjr@inethouston.net>
         * for helping track this one down. It didn't bite us in 2.0.x
         * as we always opened files read-write in that release. JRA.
         */

        if ((accmode == O_RDONLY) && ((flags & O_TRUNC) == O_TRUNC)) {
                DEBUG(10,("open_file: truncate requested on read-only open for file %s\n",fname ));
                local_flags = (flags & ~O_ACCMODE)|O_RDWR;
        }

        if ((desired_access & (FILE_READ_DATA|FILE_WRITE_DATA|FILE_APPEND_DATA|FILE_EXECUTE)) ||
                        (local_flags & O_CREAT) || ((local_flags & O_TRUNC) == O_TRUNC) ) {

                /*
                 * We can't actually truncate here as the file may be locked.
                 * open_file_shared will take care of the truncate later. JRA.
                 */

                local_flags &= ~O_TRUNC;

#if defined(O_NONBLOCK) && defined(S_ISFIFO)
                /*
                 * We would block on opening a FIFO with no one else on the
                 * other end. Do what we used to do and add O_NONBLOCK to the
                 * open flags. JRA.
                 */

                if (VALID_STAT(*psbuf) && S_ISFIFO(psbuf->st_mode))
                        local_flags |= O_NONBLOCK;
#endif

                /* Don't create files with Microsoft wildcard characters. */
                if ((local_flags & O_CREAT) && !VALID_STAT(*psbuf) && ms_has_wild(fname))  {
                        set_saved_error_triple(ERRDOS, ERRinvalidname, NT_STATUS_OBJECT_NAME_INVALID);
                        return False;
                }

                /* Actually do the open */
                fsp->fd = fd_open(conn, fname, local_flags, mode);
                if (fsp->fd == -1)  {
                        DEBUG(3,("Error opening file %s (%s) (local_flags=%d) (flags=%d)\n",
                                 fname,strerror(errno),local_flags,flags));
                        check_for_pipe(fname);
                        return False;
                }

                /* Inherit the ACL if the file was created. */
                if ((local_flags & O_CREAT) && !VALID_STAT(*psbuf))
                        inherit_access_acl(conn, fname, mode);

        } else
                fsp->fd = -1; /* What we used to call a stat open. */

        if (!VALID_STAT(*psbuf)) {
                int ret;

                if (fsp->fd == -1)
                        ret = SMB_VFS_STAT(conn, fname, psbuf);
                else {
                        ret = SMB_VFS_FSTAT(fsp,fsp->fd,psbuf);
                        /* If we have an fd, this stat should succeed. */
                        if (ret == -1)
                                DEBUG(0,("Error doing fstat on open file %s (%s)\n", fname,strerror(errno) ));
                }

                /* For a non-io open, this stat failing means file not found. JRA */
                if (ret == -1) {
                        fd_close(conn, fsp);
                        return False;
                }
        }

        /*
         * POSIX allows read-only opens of directories. We don't
         * want to do this (we use a different code path for this)
         * so catch a directory open and return an EISDIR. JRA.
         */

        if(S_ISDIR(psbuf->st_mode)) {
                fd_close(conn, fsp);
                errno = EISDIR;
                return False;
        }

        fsp->mode = psbuf->st_mode;
        fsp->inode = psbuf->st_ino;
        fsp->dev = psbuf->st_dev;
        fsp->vuid = current_user.vuid;
        fsp->file_pid = global_smbpid;
        fsp->size = psbuf->st_size;
        fsp->can_lock = True;
        fsp->can_read = ((flags & O_WRONLY)==0);
        fsp->can_write = ((flags & (O_WRONLY|O_RDWR))!=0);
        fsp->share_mode = 0;
        fsp->desired_access = desired_access;
        fsp->print_file = False;
        fsp->modified = False;
        fsp->oplock_type = NO_OPLOCK;
        fsp->sent_oplock_break = NO_BREAK_SENT;
        fsp->is_directory = False;
        fsp->is_stat = False;
        fsp->directory_delete_on_close = False;
        string_set(&fsp->fsp_name,fname);
        fsp->wcp = NULL; /* Write cache pointer. */

        DEBUG(2,("%s opened file %s read=%s write=%s (numopen=%d)\n",
                 *current_user_info.smb_name ? current_user_info.smb_name : conn->user,fsp->fsp_name,
                 BOOLSTR(fsp->can_read), BOOLSTR(fsp->can_write),
                 conn->num_files_open + 1));

        errno = 0;
        return True;
}

/*******************************************************************
 Return True if the filename is one of the special executable types.
********************************************************************/

static BOOL is_executable(const char *fname)
{
        if ((fname = strrchr_m(fname,'.'))) {
                if (strequal(fname,".com") ||
                    strequal(fname,".dll") ||
                    strequal(fname,".exe") ||
                    strequal(fname,".sym")) {
                        return True;
                }
        }
        return False;
}

enum {AFAIL,AREAD,AWRITE,AALL};

/*******************************************************************
 Reproduce the share mode access table.
 This is horrendoously complex, and really can't be justified on any
 rational grounds except that this is _exactly_ what NT does. See
 the DENY1 and DENY2 tests in smbtorture for a comprehensive set of
 test routines.
********************************************************************/

static int access_table(int new_deny,int old_deny,int old_mode,
                        BOOL same_pid, BOOL isexe)
{
          if (new_deny == DENY_ALL || old_deny == DENY_ALL) return(AFAIL);

          if (same_pid) {
                  if (isexe && old_mode == DOS_OPEN_RDONLY && 
                      old_deny == DENY_DOS && new_deny == DENY_READ) {
                          return AFAIL;
                  }
                  if (!isexe && old_mode == DOS_OPEN_RDONLY && 
                      old_deny == DENY_DOS && new_deny == DENY_DOS) {
                          return AREAD;
                  }
                  if (new_deny == DENY_FCB && old_deny == DENY_DOS) {
                          if (isexe) return AFAIL;
                          if (old_mode == DOS_OPEN_RDONLY) return AFAIL;
                          return AALL;
                  }
                  if (old_mode == DOS_OPEN_RDONLY && old_deny == DENY_DOS) {
                          if (new_deny == DENY_FCB || new_deny == DENY_READ) {
                                  if (isexe) return AREAD;
                                  return AFAIL;
                          }
                  }
                  if (old_deny == DENY_FCB) {
                          if (new_deny == DENY_DOS || new_deny == DENY_FCB) return AALL;
                          return AFAIL;
                  }
          }

          if (old_deny == DENY_DOS || new_deny == DENY_DOS || 
              old_deny == DENY_FCB || new_deny == DENY_FCB) {
                  if (isexe) {
                          if (old_deny == DENY_FCB || new_deny == DENY_FCB) {
                                  return AFAIL;
                          }
                          if (old_deny == DENY_DOS) {
                                  if (new_deny == DENY_READ && 
                                      (old_mode == DOS_OPEN_RDONLY || 
                                       old_mode == DOS_OPEN_RDWR)) {
                                          return AFAIL;
                                  }
                                  if (new_deny == DENY_WRITE && 
                                      (old_mode == DOS_OPEN_WRONLY || 
                                       old_mode == DOS_OPEN_RDWR)) {
                                          return AFAIL;
                                  }
                                  return AALL;
                          }
                          if (old_deny == DENY_NONE) return AALL;
                          if (old_deny == DENY_READ) return AWRITE;
                          if (old_deny == DENY_WRITE) return AREAD;
                  }
                  /* it isn't a exe, dll, sym or com file */
                  if (old_deny == new_deny && same_pid)
                          return(AALL);    

                  if (old_deny == DENY_READ || new_deny == DENY_READ) return AFAIL;
                  if (old_mode == DOS_OPEN_RDONLY) return(AREAD);
                  
                  return(AFAIL);
          }
          
          switch (new_deny) 
                  {
                  case DENY_WRITE:
                          if (old_deny==DENY_WRITE && old_mode==DOS_OPEN_RDONLY) return(AREAD);
                          if (old_deny==DENY_READ && old_mode==DOS_OPEN_RDONLY) return(AWRITE);
                          if (old_deny==DENY_NONE && old_mode==DOS_OPEN_RDONLY) return(AALL);
                          return(AFAIL);
                  case DENY_READ:
                          if (old_deny==DENY_WRITE && old_mode==DOS_OPEN_WRONLY) return(AREAD);
                          if (old_deny==DENY_READ && old_mode==DOS_OPEN_WRONLY) return(AWRITE);
                          if (old_deny==DENY_NONE && old_mode==DOS_OPEN_WRONLY) return(AALL);
                          return(AFAIL);
                  case DENY_NONE:
                          if (old_deny==DENY_WRITE) return(AREAD);
                          if (old_deny==DENY_READ) return(AWRITE);
                          if (old_deny==DENY_NONE) return(AALL);
                          return(AFAIL);      
                  }
          return(AFAIL);      
}

/****************************************************************************
 Check if we can open a file with a share mode.
****************************************************************************/

static BOOL check_share_mode(connection_struct *conn, share_mode_entry *share, int share_mode, uint32 desired_access,
                             const char *fname, BOOL fcbopen, int *flags)
{
        int deny_mode = GET_DENY_MODE(share_mode);
        int old_open_mode = GET_OPEN_MODE(share->share_mode);
        int old_deny_mode = GET_DENY_MODE(share->share_mode);
        BOOL non_io_open_request;
        BOOL non_io_open_existing;

        /*
         * share modes = false means don't bother to check for
         * DENY mode conflict. This is a *really* bad idea :-). JRA.
         */

        if(!lp_share_modes(SNUM(conn)))
                return True;

        if (desired_access & ~(SYNCHRONIZE_ACCESS|READ_CONTROL_ACCESS|FILE_READ_ATTRIBUTES|FILE_WRITE_ATTRIBUTES)) {
                non_io_open_request = False;
        } else {
                non_io_open_request = True;
        }

        if (share->desired_access & ~(SYNCHRONIZE_ACCESS|READ_CONTROL_ACCESS|FILE_READ_ATTRIBUTES|FILE_WRITE_ATTRIBUTES)) {
                non_io_open_existing = False;
        } else {
                non_io_open_existing = True;
        }

        /*
         * Don't allow any opens once the delete on close flag has been
         * set.
         */

        if (GET_DELETE_ON_CLOSE_FLAG(share->share_mode)) {
                DEBUG(5,("check_share_mode: Failing open on file %s as delete on close flag is set.\n",
                        fname ));
                /* Use errno to map to correct error. */
                set_saved_error_triple(SMB_SUCCESS, 0, NT_STATUS_OK);
                return False;
        }

        /* this is a nasty hack, but necessary until we rewrite our open
           handling to use a NTCreateX call as the basic call.
           NT may open a file with neither read nor write access, and in
                   this case it expects the open not to conflict with any
                   existing deny modes. This happens (for example) during a
                   "xcopy /o" where the second file descriptor is used for
                   ACL sets
                   (tridge)
        */

        /*
         * This is a bit wierd - the test for desired access not having the
         * critical bits seems seems odd. Firstly, if both opens have no
         * critical bits then always ignore. Then check the "allow delete"
         * then check for either. This probably isn't quite right yet but
         * gets us much closer. JRA.
         */

        /*
         * If desired_access doesn't contain READ_DATA,WRITE_DATA,APPEND_DATA or EXECUTE
         * and the existing desired_acces then share modes don't conflict.
         */

        if (non_io_open_request && non_io_open_existing) {

                /*
                 * Wrinkle discovered by smbtorture....
                 * If both are non-io open and requester is asking for delete and current open has delete access
                 * but neither open has allowed file share delete then deny.... this is very strange and
                 * seems to be the only case in which non-io opens conflict. JRA.
                 */

                if ((desired_access & DELETE_ACCESS) && (share->desired_access & DELETE_ACCESS) && 
                                (!GET_ALLOW_SHARE_DELETE(share->share_mode) || !GET_ALLOW_SHARE_DELETE(share_mode))) {
                        DEBUG(5,("check_share_mode: Failing open on file %s as delete access requests conflict.\n",
                                fname ));
                        set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                        return False;
                }

                DEBUG(5,("check_share_mode: Allowing open on file %s as both desired access (0x%x) \
and existing desired access (0x%x) are non-data opens\n", 
                        fname, (unsigned int)desired_access, (unsigned int)share->desired_access ));
                return True;
        } else if (non_io_open_request || non_io_open_existing) {
                /*
                 * If either are non-io opens then share modes don't conflict.
                 */
                DEBUG(5,("check_share_mode: One non-io open. Allowing open on file %s as desired access (0x%x) doesn't conflict with\
existing desired access (0x%x).\n", fname, (unsigned int)desired_access, (unsigned int)share->desired_access ));
                return True;
        }

        /*
         * If delete access was requested and the existing share mode doesn't have
         * ALLOW_SHARE_DELETE then deny.
         */

        if ((desired_access & DELETE_ACCESS) && !GET_ALLOW_SHARE_DELETE(share->share_mode)) {
                DEBUG(5,("check_share_mode: Failing open on file %s as delete access requested and allow share delete not set.\n",
                        fname ));
                set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                return False;
        }

        /*
         * The inverse of the above.
         * If delete access was granted and the new share mode doesn't have
         * ALLOW_SHARE_DELETE then deny.
         */

        if ((share->desired_access & DELETE_ACCESS) && !GET_ALLOW_SHARE_DELETE(share_mode)) {
                DEBUG(5,("check_share_mode: Failing open on file %s as delete access granted and allow share delete not requested.\n",
                        fname ));
                set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                return False;
        }

#if 0
        /* Bluarc test may need this ... needs further investigation. */
        if (deny_mode == DENY_ALL || old_deny_mode == DENY_ALL) {
                set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                return False;
        }
#endif

        /*
         * If desired_access doesn't contain READ_DATA,WRITE_DATA,APPEND_DATA or EXECUTE
         * then share modes don't conflict. Likewise with existing desired access.
         */

        if ( !(desired_access & (FILE_READ_DATA|FILE_WRITE_DATA|FILE_APPEND_DATA|FILE_EXECUTE)) ||
                !(share->desired_access & (FILE_READ_DATA|FILE_WRITE_DATA|FILE_APPEND_DATA|FILE_EXECUTE)) ) {
                DEBUG(5,("check_share_mode: Allowing open on file %s as desired access (0x%x) doesn't conflict with \
existing desired access (0x%x).\n", fname, (unsigned int)desired_access, (unsigned int)share->desired_access ));
                return True;
        }

        {
                int access_allowed = access_table(deny_mode,old_deny_mode,old_open_mode,
                                                (share->pid == sys_getpid()),is_executable(fname));

                if ((access_allowed == AFAIL) ||
                        (!fcbopen && (access_allowed == AREAD && *flags == O_RDWR)) ||
                        (access_allowed == AREAD && *flags != O_RDONLY) ||
                        (access_allowed == AWRITE && *flags != O_WRONLY)) {

                        DEBUG(2,("Share violation on file (%d,%d,%d,%d,%s,fcbopen = %d, flags = %d) = %d\n",
                                deny_mode,old_deny_mode,old_open_mode,
                                (int)share->pid,fname, fcbopen, *flags, access_allowed));

                        set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                        return False;
                }

                if (access_allowed == AREAD)
                        *flags = O_RDONLY;

                if (access_allowed == AWRITE)
                        *flags = O_WRONLY;

        }

        return True;
}


#if defined(DEVELOPER)
static void validate_my_share_entries(int num, share_mode_entry *share_entry)
{
        files_struct *fsp;

        if (share_entry->pid != sys_getpid())
                return;

        fsp = file_find_dif(share_entry->dev, share_entry->inode, share_entry->share_file_id);
        if (!fsp) {
                DEBUG(0,("validate_my_share_entries: PANIC : %s\n", share_mode_str(num, share_entry) ));
                smb_panic("validate_my_share_entries: Cannot match a share entry with an open file\n");
        }

        if (((uint16)fsp->oplock_type) != share_entry->op_type) {
                pstring str;
                DEBUG(0,("validate_my_share_entries: PANIC : %s\n", share_mode_str(num, share_entry) ));
                slprintf(str, sizeof(str)-1, "validate_my_share_entries: file %s, oplock_type = 0x%x, op_type = 0x%x\n",
                                fsp->fsp_name, (unsigned int)fsp->oplock_type, (unsigned int)share_entry->op_type );
                smb_panic(str);
        }
}
#endif

struct share_mode_entry_list {
        struct share_mode_entry_list *next, *prev;
        share_mode_entry entry;
};

static void free_broken_entry_list(struct share_mode_entry_list *broken_entry_list)
{
        while (broken_entry_list) {
                struct share_mode_entry_list *broken_entry = broken_entry_list;
                DLIST_REMOVE(broken_entry_list, broken_entry);
                SAFE_FREE(broken_entry);
        }
}

/****************************************************************************
 Deal with open deny mode and oplock break processing.
 Invarient: Share mode must be locked on entry and exit.
 Returns -1 on error, or number of share modes on success (may be zero).
****************************************************************************/

static int open_mode_check(connection_struct *conn, const char *fname, SMB_DEV_T dev,
                           SMB_INO_T inode, 
                           uint32 desired_access,
                           int share_mode, int *p_flags, int *p_oplock_request,
                           BOOL *p_all_current_opens_are_level_II)
{
        int i;
        int num_share_modes;
        int oplock_contention_count = 0;
        share_mode_entry *old_shares = NULL;
        BOOL fcbopen = False;
        BOOL broke_oplock;

        if(GET_OPEN_MODE(share_mode) == DOS_OPEN_FCB)
                fcbopen = True;
        
        num_share_modes = get_share_modes(conn, dev, inode, &old_shares);
        
        if(num_share_modes == 0) {
                SAFE_FREE(old_shares);
                return 0;
        }
        
        if (desired_access && ((desired_access & ~(SYNCHRONIZE_ACCESS|FILE_READ_ATTRIBUTES|FILE_WRITE_ATTRIBUTES))==0) &&
                ((desired_access & (SYNCHRONIZE_ACCESS|FILE_READ_ATTRIBUTES|FILE_WRITE_ATTRIBUTES)) != 0)) {
                /* Stat open that doesn't trigger oplock breaks or share mode checks... ! JRA. */
                SAFE_FREE(old_shares);
                return num_share_modes;
        }

        /*
         * Check if the share modes will give us access.
         */
        
        do {
                struct share_mode_entry_list *broken_entry_list = NULL;
                struct share_mode_entry_list *broken_entry = NULL;

                broke_oplock = False;
                *p_all_current_opens_are_level_II = True;
                
                for(i = 0; i < num_share_modes; i++) {
                        BOOL cause_oplock_break = False;
                        share_mode_entry *share_entry = &old_shares[i];
                        
#if defined(DEVELOPER)
                        validate_my_share_entries(i, share_entry);
#endif

                        /* 
                         * By observation of NetBench, oplocks are broken *before* share
                         * modes are checked. This allows a file to be closed by the client
                         * if the share mode would deny access and the client has an oplock. 
                         * Check if someone has an oplock on this file. If so we must break 
                         * it before continuing. 
                         */
                        
                        /* Was this a delete this file request ? */
                        if (!*p_oplock_request && desired_access == DELETE_ACCESS &&
                                        !BATCH_OPLOCK_TYPE(share_entry->op_type)) {
                                /* Don't break the oplock in this case. */
                                cause_oplock_break = False;
                        } else if((*p_oplock_request && EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) ||
                           (!*p_oplock_request && (share_entry->op_type != NO_OPLOCK))) {
                                cause_oplock_break = True;
                        }

                        if(cause_oplock_break) {
                                BOOL opb_ret;

                                DEBUG(5,("open_mode_check: oplock_request = %d, breaking oplock (%x) on file %s, \
dev = %x, inode = %.0f\n", *p_oplock_request, share_entry->op_type, fname, (unsigned int)dev, (double)inode));
                                
                                /* Ensure the reply for the open uses the correct sequence number. */
                                /* This isn't a real deferred packet as it's response will also increment
                                 * the sequence.
                                 */
                                srv_defer_sign_response(get_current_mid());

                                /* Oplock break - unlock to request it. */
                                unlock_share_entry(conn, dev, inode);
                                
                                opb_ret = request_oplock_break(share_entry);
                                
                                /* Now relock. */
                                lock_share_entry(conn, dev, inode);
                                
                                if(opb_ret == False) {
                                        DEBUG(0,("open_mode_check: FAILED when breaking oplock (%x) on file %s, \
dev = %x, inode = %.0f\n", old_shares[i].op_type, fname, (unsigned int)dev, (double)inode));
                                        SAFE_FREE(old_shares);
                                        set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                                        return -1;
                                }
                                
                                broken_entry = SMB_MALLOC_P(struct share_mode_entry_list);
                                if (!broken_entry) {
                                        smb_panic("open_mode_check: malloc fail.\n");
                                }
                                broken_entry->entry = *share_entry;
                                DLIST_ADD(broken_entry_list, broken_entry);
                                broke_oplock = True;
                                
                        } else if (!LEVEL_II_OPLOCK_TYPE(share_entry->op_type)) {
                                *p_all_current_opens_are_level_II = False;
                        }
                } /* end for */
                
                if (broke_oplock) {
                        /* Update the current open table. */
                        SAFE_FREE(old_shares);
                        num_share_modes = get_share_modes(conn, dev, inode, &old_shares);
                }

                /* Now we check the share modes, after any oplock breaks. */
                for(i = 0; i < num_share_modes; i++) {
                        share_mode_entry *share_entry = &old_shares[i];

                        /* someone else has a share lock on it, check to see if we can too */
                        if (!check_share_mode(conn, share_entry, share_mode, desired_access,
                                                fname, fcbopen, p_flags)) {
                                SAFE_FREE(old_shares);
                                free_broken_entry_list(broken_entry_list);
                                errno = EACCES;
                                return -1;
                        }
                }

                for(broken_entry = broken_entry_list; broken_entry; broken_entry = broken_entry->next) {
                        oplock_contention_count++;
                        
                        /* Paranoia check that this is no longer an exlusive entry. */
                        for(i = 0; i < num_share_modes; i++) {
                                share_mode_entry *share_entry = &old_shares[i];
                                
                                if (share_modes_identical(&broken_entry->entry, share_entry) && 
                                            EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type) ) {
                                        
                                        /*
                                         * This should not happen. The target left this oplock
                                         * as exlusive.... The process *must* be dead.... 
                                         */
                                        
                                        DEBUG(0,("open_mode_check: exlusive oplock left by process %d \
after break ! For file %s, dev = %x, inode = %.0f. Deleting it to continue...\n",
                                                (int)broken_entry->entry.pid, fname, (unsigned int)dev, (double)inode));
                                        
                                        if (process_exists(broken_entry->entry.pid)) {
                                                DEBUG(0,("open_mode_check: Existent process %lu left active oplock.\n",
                                                         (unsigned long)broken_entry->entry.pid ));
                                        }
                                        
                                        if (del_share_entry(dev, inode, &broken_entry->entry, NULL) == -1) {
                                                free_broken_entry_list(broken_entry_list);
                                                errno = EACCES;
                                                set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                                                return -1;
                                        }
                                        
                                        /*
                                         * We must reload the share modes after deleting the 
                                         * other process's entry.
                                         */
                                        
                                        SAFE_FREE(old_shares);
                                        num_share_modes = get_share_modes(conn, dev, inode, &old_shares);
                                        break;
                                }
                        } /* end for paranoia... */
                } /* end for broken_entry */
                free_broken_entry_list(broken_entry_list);
        } while(broke_oplock);
        
        /*
         * Refuse to grant an oplock in case the contention limit is
         * reached when going through the lock list multiple times.
         */
        
        if(oplock_contention_count >= lp_oplock_contention_limit(SNUM(conn))) {
                *p_oplock_request = 0;
                DEBUG(4,("open_mode_check: oplock contention = %d. Not granting oplock.\n",
                         oplock_contention_count ));
        }
        
        SAFE_FREE(old_shares);
        return num_share_modes;
}

/****************************************************************************
 Delete the record for a handled deferred open entry.
****************************************************************************/

static void delete_defered_open_entry_record(connection_struct *conn, SMB_DEV_T dev, SMB_INO_T inode)
{
        uint16 mid = get_current_mid();
        pid_t mypid = sys_getpid();
        deferred_open_entry *de_array = NULL;
        int num_de_entries, i;

        if (!lp_defer_sharing_violations()) {
                return;
        }

        num_de_entries = get_deferred_opens(conn, dev, inode, &de_array);
        for (i = 0; i < num_de_entries; i++) {
                deferred_open_entry *entry = &de_array[i];
                if (entry->pid == mypid && entry->mid == mid && entry->dev == dev &&
                        entry->inode == inode) {

                        /* Remove the deferred open entry from the array. */
                        delete_deferred_open_entry(entry);
                        SAFE_FREE(de_array);
                        return;
                }
        }
        SAFE_FREE(de_array);
}

/****************************************************************************
 Handle the 1 second delay in returning a SHARING_VIOLATION error.
****************************************************************************/

void defer_open_sharing_error(connection_struct *conn, struct timeval *ptv,
                char *fname, SMB_DEV_T dev, SMB_INO_T inode)
{
        uint16 mid = get_current_mid();
        pid_t mypid = sys_getpid();
        deferred_open_entry *de_array = NULL;
        int num_de_entries, i;
        struct dev_inode_bundle dib;

        if (!lp_defer_sharing_violations()) {
                return;
        }

        dib.dev = dev;
        dib.inode = inode;

        num_de_entries = get_deferred_opens(conn, dev, inode, &de_array);
        for (i = 0; i < num_de_entries; i++) {
                deferred_open_entry *entry = &de_array[i];
                if (entry->pid == mypid && entry->mid == mid) {
                        /*
                         * Check if a 1 second timeout has expired.
                         */
                        if (usec_time_diff(ptv, &entry->time) > SHARING_VIOLATION_USEC_WAIT) {
                                DEBUG(10,("defer_open_sharing_error: Deleting deferred open entry for mid %u, \
file %s\n",
                                        (unsigned int)mid, fname ));

                                /* Expired, return a real error. */
                                /* Remove the deferred open entry from the array. */

                                delete_deferred_open_entry(entry);
                                SAFE_FREE(de_array);
                                return;
                        }
                        /*
                         * If the timeout hasn't expired yet and we still have a sharing violation,
                         * just leave the entry in the deferred open array alone. We do need to
                         * reschedule this open call though (with the original created time).
                         */
                        DEBUG(10,("defer_open_sharing_error: time [%u.%06u] updating \
deferred open entry for mid %u, file %s\n",
                                (unsigned int)entry->time.tv_sec,
                                (unsigned int)entry->time.tv_usec,
                                (unsigned int)mid, fname ));

                        push_sharing_violation_open_smb_message(&entry->time, (char *)&dib, sizeof(dib));
                        SAFE_FREE(de_array);
                        return;
                }
        }

        DEBUG(10,("defer_open_sharing_error: time [%u.%06u] adding deferred open entry for mid %u, file %s\n",
                (unsigned int)ptv->tv_sec, (unsigned int)ptv->tv_usec, (unsigned int)mid, fname ));

        if (!push_sharing_violation_open_smb_message(ptv, (char *)&dib, sizeof(dib))) {
                SAFE_FREE(de_array);
                return;
        }
        if (!add_deferred_open(mid, ptv, dev, inode, global_oplock_port, fname)) {
                remove_sharing_violation_open_smb_message(mid);
        }

        /*
         * Push the MID of this packet on the signing queue.
         * We only do this once, the first time we push the packet
         * onto the deferred open queue, as this has a side effect
         * of incrementing the response sequence number.
         */

        srv_defer_sign_response(mid);

        SAFE_FREE(de_array);
}

/****************************************************************************
 Set a kernel flock on a file for NFS interoperability.
 This requires a patch to Linux.
****************************************************************************/

static void kernel_flock(files_struct *fsp, int deny_mode)
{
#if HAVE_KERNEL_SHARE_MODES
        int kernel_mode = 0;
        if (deny_mode == DENY_READ) kernel_mode = LOCK_MAND|LOCK_WRITE;
        else if (deny_mode == DENY_WRITE) kernel_mode = LOCK_MAND|LOCK_READ;
        else if (deny_mode == DENY_ALL) kernel_mode = LOCK_MAND;
        if (kernel_mode) flock(fsp->fd, kernel_mode);
#endif
        ;;
}


static BOOL open_match_attributes(connection_struct *conn, const char *path, uint32 old_dos_mode, uint32 new_dos_mode,
                mode_t existing_mode, mode_t new_mode, mode_t *returned_mode)
{
        uint32 noarch_old_dos_mode, noarch_new_dos_mode;

        noarch_old_dos_mode = (old_dos_mode & ~FILE_ATTRIBUTE_ARCHIVE);
        noarch_new_dos_mode = (new_dos_mode & ~FILE_ATTRIBUTE_ARCHIVE);

        if((noarch_old_dos_mode == 0 && noarch_new_dos_mode != 0) || 
           (noarch_old_dos_mode != 0 && ((noarch_old_dos_mode & noarch_new_dos_mode) == noarch_old_dos_mode)))
                *returned_mode = new_mode;
        else
                *returned_mode = (mode_t)0;

        DEBUG(10,("open_match_attributes: file %s old_dos_mode = 0x%x, existing_mode = 0%o, new_dos_mode = 0x%x returned_mode = 0%o\n",
                path,
                old_dos_mode, (unsigned int)existing_mode, new_dos_mode, (unsigned int)*returned_mode ));

        /* If we're mapping SYSTEM and HIDDEN ensure they match. */
        if (lp_map_system(SNUM(conn)) || lp_store_dos_attributes(SNUM(conn))) {
                if ((old_dos_mode & FILE_ATTRIBUTE_SYSTEM) && !(new_dos_mode & FILE_ATTRIBUTE_SYSTEM))
                        return False;
        }
        if (lp_map_hidden(SNUM(conn)) || lp_store_dos_attributes(SNUM(conn))) {
                if ((old_dos_mode & FILE_ATTRIBUTE_HIDDEN) && !(new_dos_mode & FILE_ATTRIBUTE_HIDDEN))
                        return False;
        }
        return True;
}

/****************************************************************************
 Open a file with a share mode.
****************************************************************************/

files_struct *open_file_shared(connection_struct *conn,char *fname, SMB_STRUCT_STAT *psbuf, 
                               int share_mode,int ofun, uint32 new_dos_mode, int oplock_request, 
                               int *Access,int *action)
{
        return open_file_shared1(conn, fname, psbuf, 0, share_mode, ofun, new_dos_mode,
                                 oplock_request, Access, action);
}

/****************************************************************************
 Open a file with a share mode.
****************************************************************************/

files_struct *open_file_shared1(connection_struct *conn,char *fname, SMB_STRUCT_STAT *psbuf, 
                                uint32 desired_access, 
                                int share_mode,int ofun, uint32 new_dos_mode,
                                int oplock_request, 
                                int *Access,int *paction)
{
        int flags=0;
        int flags2=0;
        int deny_mode = GET_DENY_MODE(share_mode);
        BOOL allow_share_delete = GET_ALLOW_SHARE_DELETE(share_mode);
        BOOL delete_on_close = GET_DELETE_ON_CLOSE_FLAG(share_mode);
        BOOL file_existed = VALID_STAT(*psbuf);
        BOOL fcbopen = False;
        BOOL def_acl = False;
        BOOL add_share_mode = True;
        BOOL internal_only_open = False;
        SMB_DEV_T dev = 0;
        SMB_INO_T inode = 0;
        int num_share_modes = 0;
        BOOL all_current_opens_are_level_II = False;
        BOOL fsp_open = False;
        files_struct *fsp = NULL;
        int open_mode=0;
        uint16 port = 0;
        mode_t new_mode = (mode_t)0;
        int action;
        uint32 existing_dos_mode = 0;
        struct pending_message_list *pml = NULL;
        uint16 mid = get_current_mid();
        /* We add aARCH to this as this mode is only used if the file is created new. */
        mode_t mode = unix_mode(conn,new_dos_mode | aARCH,fname, True);

        if (oplock_request == INTERNAL_OPEN_ONLY) {
                internal_only_open = True;
                oplock_request = 0;
        }

        if ((pml = get_open_deferred_message(mid)) != NULL) {
                struct dev_inode_bundle dib;

                memcpy(&dib, pml->private_data.data, sizeof(dib));

                /* There could be a race condition where the dev/inode pair
                        has changed since we deferred the message. If so, just
                        remove the deferred open entry and return sharing violation. */

                /* If the timeout value is non-zero, we need to just
                        return sharing violation. Don't retry the open
                        as we were not notified of a close and we don't want to
                        trigger another spurious oplock break. */

                if (!file_existed || dib.dev != psbuf->st_dev || dib.inode != psbuf->st_ino ||
                                pml->msg_time.tv_sec || pml->msg_time.tv_usec) {
                        /* Ensure we don't reprocess this message. */
                        remove_sharing_violation_open_smb_message(mid);

                        /* Now remove the deferred open entry under lock. */
                        lock_share_entry(conn, dib.dev, dib.inode);
                        delete_defered_open_entry_record(conn, dib.dev, dib.inode);
                        unlock_share_entry(conn, dib.dev, dib.inode);

                        set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                        return NULL;
                }
                /* Ensure we don't reprocess this message. */
                remove_sharing_violation_open_smb_message(mid);

        }

        if (conn->printer) {
                /* printers are handled completely differently. Most of the passed parameters are
                        ignored */
                if (Access)
                        *Access = DOS_OPEN_WRONLY;
                if (paction)
                        *paction = FILE_WAS_CREATED;
                return print_fsp_open(conn, fname);
        }

        switch(ofun) {
                case FILE_EXISTS_OPEN:
                case FILE_EXISTS_TRUNCATE:
                case FILE_EXISTS_FAIL | FILE_CREATE_IF_NOT_EXIST:
                case FILE_EXISTS_OPEN | FILE_CREATE_IF_NOT_EXIST:
                case FILE_EXISTS_TRUNCATE | FILE_CREATE_IF_NOT_EXIST:
                        break; /* These are ok. */
                default:
                        if (GET_OPEN_MODE(share_mode) == DOS_OPEN_EXEC) {
                                ofun = FILE_EXISTS_FAIL | FILE_CREATE_IF_NOT_EXIST;
                                break;
                        }
                        /* Cause caller to force dos errors. */
                        set_saved_error_triple(ERRDOS, ERRbadaccess, NT_STATUS_INVALID);
                        return NULL;
        }

        DEBUG(10,("open_file_shared: fname = %s, dos_attrs = %x, share_mode = %x, ofun = %x, mode = %o, oplock request = %d\n",
                fname, new_dos_mode, share_mode, ofun, (int)mode,  oplock_request ));

        if (!check_name(fname,conn)) {
                return NULL;
        } 

        new_dos_mode &= SAMBA_ATTRIBUTES_MASK;
        if (file_existed) {
                existing_dos_mode = dos_mode(conn, fname, psbuf);
        }

        /* ignore any oplock requests if oplocks are disabled */
        if (!lp_oplocks(SNUM(conn)) || global_client_failed_oplock_break) {
                oplock_request = 0;
        }

        /* this is for OS/2 long file names - say we don't support them */
        if (strstr(fname,".+,;=[].")) {
                /* OS/2 Workplace shell fix may be main code stream in a later release. */ 
                set_saved_error_triple(ERRDOS, ERRcannotopen, NT_STATUS_OBJECT_NAME_NOT_FOUND);
                DEBUG(5,("open_file_shared: OS/2 long filenames are not supported.\n"));
                return NULL;
        }

        if ((GET_FILE_OPEN_DISPOSITION(ofun) == FILE_EXISTS_FAIL) && file_existed)  {
                DEBUG(5,("open_file_shared: create new requested for file %s and file already exists.\n",
                        fname ));
                if (S_ISDIR(psbuf->st_mode)) {
                        errno = EISDIR;
                } else {
                        errno = EEXIST;
                }
                return NULL;
        }
      
        if (CAN_WRITE(conn) && (GET_FILE_CREATE_DISPOSITION(ofun) == FILE_CREATE_IF_NOT_EXIST))
                flags2 |= O_CREAT;

        if (CAN_WRITE(conn) && (GET_FILE_OPEN_DISPOSITION(ofun) == FILE_EXISTS_TRUNCATE))
                flags2 |= O_TRUNC;

        /* We only care about matching attributes on file exists and truncate. */
        if (file_existed && (GET_FILE_OPEN_DISPOSITION(ofun) == FILE_EXISTS_TRUNCATE)) {
                if (!open_match_attributes(conn, fname, existing_dos_mode, new_dos_mode,
                                        psbuf->st_mode, mode, &new_mode)) {
                        DEBUG(5,("open_file_shared: attributes missmatch for file %s (%x %x) (0%o, 0%o)\n",
                                                fname, existing_dos_mode, new_dos_mode,
                                                (int)psbuf->st_mode, (int)mode ));
                        errno = EACCES;
                        return NULL;
                }
        }

        if (GET_FILE_OPEN_DISPOSITION(ofun) == FILE_EXISTS_FAIL)
                flags2 |= O_EXCL;

        /* note that we ignore the append flag as 
                append does not mean the same thing under dos and unix */

        switch (GET_OPEN_MODE(share_mode)) {
                case DOS_OPEN_RDONLY:
                        flags = O_RDONLY;
                        if (desired_access == 0)
                                desired_access = FILE_READ_DATA;
                        break;
                case DOS_OPEN_WRONLY: 
                        flags = O_WRONLY; 
                        if (desired_access == 0)
                                desired_access = FILE_WRITE_DATA;
                        break;
                case DOS_OPEN_FCB: 
                        fcbopen = True;
                        flags = O_RDWR; 
                        if (desired_access == 0)
                                desired_access = FILE_READ_DATA|FILE_WRITE_DATA;
                        break;
                case DOS_OPEN_RDWR: 
                case DOS_OPEN_EXEC:
                        flags = O_RDWR; 
                        if (desired_access == 0)
                                desired_access = FILE_READ_DATA|FILE_WRITE_DATA;
                        break;
                default:
                        /* Force DOS error. */
                        set_saved_error_triple(ERRDOS, ERRinvalidparam, NT_STATUS_INVALID);
                        return NULL;
        }

#if defined(O_SYNC)
        if (GET_FILE_SYNC_OPENMODE(share_mode)) {
                flags2 |= O_SYNC;
        }
#endif /* O_SYNC */
  
        if (flags != O_RDONLY && file_existed && 
                        (!CAN_WRITE(conn) || IS_DOS_READONLY(existing_dos_mode))) {
                if (!fcbopen) {
                        DEBUG(5,("open_file_shared: read/write access requested for file %s on read only %s\n",
                                fname, !CAN_WRITE(conn) ? "share" : "file" ));
                        errno = EACCES;
                        return NULL;
                }
                flags = O_RDONLY;
        }

        if (deny_mode > DENY_NONE && deny_mode!=DENY_FCB) {
                DEBUG(2,("Invalid deny mode %d on file %s\n",deny_mode,fname));
                errno = EINVAL;
                return NULL;
        }

        if (desired_access && ((desired_access & ~(SYNCHRONIZE_ACCESS|FILE_READ_ATTRIBUTES|FILE_WRITE_ATTRIBUTES))==0) &&
                ((desired_access & (SYNCHRONIZE_ACCESS|FILE_READ_ATTRIBUTES|FILE_WRITE_ATTRIBUTES)) != 0)) {
                /* Stat open that doesn't trigger oplock breaks or share mode checks... ! JRA. */
                deny_mode = DENY_NONE;
                if (file_existed) {
                        oplock_request = 0;
                        add_share_mode = False;
                        flags2 &= ~O_CREAT;
                }
        }

        fsp = file_new(conn);
        if(!fsp)
                return NULL;

        if (file_existed) {

                dev = psbuf->st_dev;
                inode = psbuf->st_ino;

                lock_share_entry(conn, dev, inode);

                num_share_modes = open_mode_check(conn, fname, dev, inode, 
                                                  desired_access,
                                                  share_mode,
                                                  &flags, &oplock_request, &all_current_opens_are_level_II);
                if(num_share_modes == -1) {

                        /*
                         * This next line is a subtlety we need for MS-Access. If a file open will
                         * fail due to share permissions and also for security (access)
                         * reasons, we need to return the access failed error, not the
                         * share error. This means we must attempt to open the file anyway
                         * in order to get the UNIX access error - even if we're going to
                         * fail the open for share reasons. This is bad, as we're burning
                         * another fd if there are existing locks but there's nothing else
                         * we can do. We also ensure we're not going to create or tuncate
                         * the file as we only want an access decision at this stage. JRA.
                         */
                        errno = 0;
                        fsp_open = open_file(fsp,conn,fname,psbuf,
                                                flags|(flags2&~(O_TRUNC|O_CREAT)),mode,desired_access);

                        DEBUG(4,("open_file_shared : share_mode deny - calling open_file with \
flags=0x%X flags2=0x%X mode=0%o returned %d\n",
                                flags,(flags2&~(O_TRUNC|O_CREAT)),(int)mode,(int)fsp_open ));

                        if (!fsp_open && errno) {
                                /* Default error. */
                                set_saved_error_triple(ERRDOS, ERRnoaccess, NT_STATUS_ACCESS_DENIED);
                        }

                        /* 
                         * If we're returning a share violation, ensure we cope with
                         * the braindead 1 second delay.
                         */

                        if (!internal_only_open) {
                                NTSTATUS status;
                                get_saved_error_triple(NULL, NULL, &status);
                                if (NT_STATUS_EQUAL(status,NT_STATUS_SHARING_VIOLATION)) {
                                        /* The fsp->open_time here represents the current time of day. */
                                        defer_open_sharing_error(conn, &fsp->open_time, fname, dev, inode);
                                }
                        }

                        unlock_share_entry(conn, dev, inode);
                        if (fsp_open) {
                                fd_close(conn, fsp);
                                /*
                                 * We have detected a sharing violation here
                                 * so return the correct error code
                                 */
                                set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                        }
                        file_free(fsp);
                        return NULL;
                }

                /*
                 * We exit this block with the share entry *locked*.....
                 */
        }

        /*
         * Ensure we pay attention to default ACLs on directories if required.
         */

        if ((flags2 & O_CREAT) && lp_inherit_acls(SNUM(conn)) &&
                        (def_acl = directory_has_default_acl(conn, parent_dirname(fname))))
                mode = 0777;

        DEBUG(4,("calling open_file with flags=0x%X flags2=0x%X mode=0%o\n",
                        flags,flags2,(int)mode));

        /*
         * open_file strips any O_TRUNC flags itself.
         */

        fsp_open = open_file(fsp,conn,fname,psbuf,flags|flags2,mode,desired_access);

        if (!fsp_open && (flags == O_RDWR) && (errno != ENOENT) && fcbopen) {
                if((fsp_open = open_file(fsp,conn,fname,psbuf,O_RDONLY,mode,desired_access)) == True)
                        flags = O_RDONLY;
        }

        if (!fsp_open) {
                if(file_existed)
                        unlock_share_entry(conn, dev, inode);
                file_free(fsp);
                return NULL;
        }

        /*
         * Deal with the race condition where two smbd's detect the file doesn't
         * exist and do the create at the same time. One of them will win and
         * set a share mode, the other (ie. this one) should check if the
         * requested share mode for this create is allowed.
         */

        if (!file_existed) { 

                /*
                 * Now the file exists and fsp is successfully opened,
                 * fsp->dev and fsp->inode are valid and should replace the
                 * dev=0,inode=0 from a non existent file. Spotted by
                 * Nadav Danieli <nadavd@exanet.com>. JRA.
                 */

                dev = fsp->dev;
                inode = fsp->inode;

                lock_share_entry_fsp(fsp);

                num_share_modes = open_mode_check(conn, fname, dev, inode, 
                                                  desired_access,
                                                  share_mode,
                                                  &flags, &oplock_request, &all_current_opens_are_level_II);

                if(num_share_modes == -1) {
                        /* 
                         * If we're returning a share violation, ensure we cope with
                         * the braindead 1 second delay.
                         */

                        NTSTATUS status;
                        get_saved_error_triple(NULL, NULL, &status);
                        if (NT_STATUS_EQUAL(status,NT_STATUS_SHARING_VIOLATION)) {
                                /* The fsp->open_time here represents the current time of day. */
                                defer_open_sharing_error(conn, &fsp->open_time, fname, dev, inode);
                        }

                        unlock_share_entry_fsp(fsp);
                        fd_close(conn,fsp);
                        file_free(fsp);
                        /*
                         * We have detected a sharing violation here, so
                         * return the correct code.
                         */
                        set_saved_error_triple(ERRDOS, ERRbadshare, NT_STATUS_SHARING_VIOLATION);
                        return NULL;
                }

                /*
                 * If there are any share modes set then the file *did*
                 * exist. Ensure we return the correct value for action.
                 */

                if (num_share_modes > 0)
                        file_existed = True;

                /*
                 * We exit this block with the share entry *locked*.....
                 */
        }

        /* note that we ignore failure for the following. It is
           basically a hack for NFS, and NFS will never set one of
           these only read them. Nobody but Samba can ever set a deny
           mode and we have already checked our more authoritative
           locking database for permission to set this deny mode. If
           the kernel refuses the operations then the kernel is wrong */
        kernel_flock(fsp, deny_mode);

        /*
         * At this point onwards, we can guarentee that the share entry
         * is locked, whether we created the file or not, and that the
         * deny mode is compatible with all current opens.
         */

        /*
         * If requested, truncate the file.
         */

        if (flags2&O_TRUNC) {
                /*
                 * We are modifing the file after open - update the stat struct..
                 */
                if ((SMB_VFS_FTRUNCATE(fsp,fsp->fd,0) == -1) || (SMB_VFS_FSTAT(fsp,fsp->fd,psbuf)==-1)) {
                        unlock_share_entry_fsp(fsp);
                        fd_close(conn,fsp);
                        file_free(fsp);
                        return NULL;
                }
        }

        switch (flags) {
                case O_RDONLY:
                        open_mode = DOS_OPEN_RDONLY;
                        break;
                case O_RDWR:
                        open_mode = DOS_OPEN_RDWR;
                        break;
                case O_WRONLY:
                        open_mode = DOS_OPEN_WRONLY;
                        break;
        }

        fsp->share_mode = SET_DENY_MODE(deny_mode) | 
                                                SET_OPEN_MODE(open_mode) | 
                                                SET_ALLOW_SHARE_DELETE(allow_share_delete);

        DEBUG(10,("open_file_shared : share_mode = %x\n", fsp->share_mode ));

        if (Access) {
                (*Access) = open_mode;
        }

        action = 0;

        if (file_existed && !(flags2 & O_TRUNC))
                action = FILE_WAS_OPENED;
        if (file_existed && (flags2 & O_TRUNC))
                action = FILE_WAS_OVERWRITTEN;
        if (!file_existed) {
                action = FILE_WAS_CREATED;
                /* Change the owner if required. */
                if (lp_inherit_owner(SNUM(conn))) {
                        change_owner_to_parent(conn, fsp, fsp->fsp_name, psbuf);
                }
        }

        if (paction) {
                *paction = action;
        }

        /* 
         * Setup the oplock info in both the shared memory and
         * file structs.
         */

        if(oplock_request && (num_share_modes == 0) && 
                        !IS_VETO_OPLOCK_PATH(conn,fname) && set_file_oplock(fsp, oplock_request) ) {
                port = global_oplock_port;
        } else if (oplock_request && all_current_opens_are_level_II) {
                port = global_oplock_port;
                oplock_request = LEVEL_II_OPLOCK;
                set_file_oplock(fsp, oplock_request);
        } else {
                port = 0;
                oplock_request = 0;
        }

        if (add_share_mode) {
                set_share_mode(fsp, port, oplock_request);
        }

        if (delete_on_close) {
                uint32 dosmode = existing_dos_mode;
                NTSTATUS result;

                if (action == FILE_WAS_OVERWRITTEN || action == FILE_WAS_CREATED) {
                        dosmode = new_dos_mode;
                }
                result = set_delete_on_close_internal(fsp, delete_on_close, dosmode);

                if (NT_STATUS_V(result) !=  NT_STATUS_V(NT_STATUS_OK)) {
                        uint8 u_e_c;
                        uint32 u_e_code;
                        /* Remember to delete the mode we just added. */
                        if (add_share_mode) {
                                del_share_mode(fsp, NULL);
                        }
                        unlock_share_entry_fsp(fsp);
                        fd_close(conn,fsp);
                        file_free(fsp);
                        ntstatus_to_dos(result, &u_e_c, &u_e_code);
                        set_saved_error_triple(u_e_c, u_e_code, result);
                        return NULL;
                }
        }
        
        if (action == FILE_WAS_OVERWRITTEN || action == FILE_WAS_CREATED) {
                /* Files should be initially set as archive */
                if (lp_map_archive(SNUM(conn)) || lp_store_dos_attributes(SNUM(conn))) {
                        file_set_dosmode(conn, fname, new_dos_mode | aARCH, NULL, True);
                }
        }

        /*
         * Take care of inherited ACLs on created files - if default ACL not
         * selected.
         */

        if (!file_existed && !def_acl) {

                int saved_errno = errno; /* We might get ENOSYS in the next call.. */

                if (SMB_VFS_FCHMOD_ACL(fsp, fsp->fd, mode) == -1 && errno == ENOSYS)
                        errno = saved_errno; /* Ignore ENOSYS */

        } else if (new_mode) {

                int ret = -1;

                /* Attributes need changing. File already existed. */

                {
                        int saved_errno = errno; /* We might get ENOSYS in the next call.. */
                        ret = SMB_VFS_FCHMOD_ACL(fsp, fsp->fd, new_mode);

                        if (ret == -1 && errno == ENOSYS) {
                                errno = saved_errno; /* Ignore ENOSYS */
                        } else {
                                DEBUG(5, ("open_file_shared: failed to reset attributes of file %s to 0%o\n",
                                        fname, (int)new_mode));
                                ret = 0; /* Don't do the fchmod below. */
                        }
                }

                if ((ret == -1) && (SMB_VFS_FCHMOD(fsp, fsp->fd, new_mode) == -1))
                        DEBUG(5, ("open_file_shared: failed to reset attributes of file %s to 0%o\n",
                                fname, (int)new_mode));
        }

        /* If this is a successful open, we must remove any deferred open records. */
        delete_defered_open_entry_record(conn, fsp->dev, fsp->inode);
        unlock_share_entry_fsp(fsp);

        conn->num_files_open++;

        return fsp;
}

/****************************************************************************
 Open a file for for write to ensure that we can fchmod it.
****************************************************************************/

files_struct *open_file_fchmod(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf)
{
        files_struct *fsp = NULL;
        BOOL fsp_open;

        if (!VALID_STAT(*psbuf))
                return NULL;

        fsp = file_new(conn);
        if(!fsp)
                return NULL;

        /* note! we must use a non-zero desired access or we don't get
           a real file descriptor. Oh what a twisted web we weave. */
        fsp_open = open_file(fsp,conn,fname,psbuf,O_WRONLY,0,FILE_WRITE_DATA);

        /* 
         * This is not a user visible file open.
         * Don't set a share mode and don't increment
         * the conn->num_files_open.
         */

        if (!fsp_open) {
                file_free(fsp);
                return NULL;
        }

        return fsp;
}

/****************************************************************************
 Close the fchmod file fd - ensure no locks are lost.
****************************************************************************/

int close_file_fchmod(files_struct *fsp)
{
        int ret = fd_close(fsp->conn, fsp);
        file_free(fsp);
        return ret;
}

/****************************************************************************
 Open a directory from an NT SMB call.
****************************************************************************/

files_struct *open_directory(connection_struct *conn, const char *fname, SMB_STRUCT_STAT *psbuf,
                        uint32 desired_access, int share_mode, int smb_ofun, int *action)
{
        extern struct current_user current_user;
        BOOL got_stat = False;
        files_struct *fsp = file_new(conn);
        BOOL delete_on_close = GET_DELETE_ON_CLOSE_FLAG(share_mode);

        if(!fsp)
                return NULL;

        if (VALID_STAT(*psbuf))
                got_stat = True;

        if (got_stat && (GET_FILE_OPEN_DISPOSITION(smb_ofun) == FILE_EXISTS_FAIL)) {
                file_free(fsp);
                errno = EEXIST; /* Setup so correct error is returned to client. */
                return NULL;
        }

        if (GET_FILE_CREATE_DISPOSITION(smb_ofun) == FILE_CREATE_IF_NOT_EXIST) {

                if (got_stat) {

                        if(!S_ISDIR(psbuf->st_mode)) {
                                DEBUG(0,("open_directory: %s is not a directory !\n", fname ));
                                file_free(fsp);
                                errno = EACCES;
                                return NULL;
                        }
                        *action = FILE_WAS_OPENED;

                } else {

                        /*
                         * Try and create the directory.
                         */

                        /* We know bad_path is false as it's caught earlier. */

                        NTSTATUS status = mkdir_internal(conn, fname, False);

                        if (!NT_STATUS_IS_OK(status)) {
                                DEBUG(2,("open_directory: unable to create %s. Error was %s\n",
                                         fname, strerror(errno) ));
                                file_free(fsp);
                                /* Ensure we return the correct NT status to the client. */
                                set_saved_error_triple(0, 0, status);
                                return NULL;
                        }

                        /* Ensure we're checking for a symlink here.... */
                        /* We don't want to get caught by a symlink racer. */

                        if(SMB_VFS_LSTAT(conn,fname, psbuf) != 0) {
                                file_free(fsp);
                                return NULL;
                        }

                        if(!S_ISDIR(psbuf->st_mode)) {
                                DEBUG(0,("open_directory: %s is not a directory !\n", fname ));
                                file_free(fsp);
                                return NULL;
                        }

                        *action = FILE_WAS_CREATED;

                }
        } else {

                /*
                 * Don't create - just check that it *was* a directory.
                 */

                if(!got_stat) {
                        DEBUG(3,("open_directory: unable to stat name = %s. Error was %s\n",
                                 fname, strerror(errno) ));
                        file_free(fsp);
                        return NULL;
                }

                if(!S_ISDIR(psbuf->st_mode)) {
                        DEBUG(0,("open_directory: %s is not a directory !\n", fname ));
                        file_free(fsp);
                        return NULL;
                }

                *action = FILE_WAS_OPENED;
        }
        
        DEBUG(5,("open_directory: opening directory %s\n", fname));

        /*
         * Setup the files_struct for it.
         */
        
        fsp->mode = psbuf->st_mode;
        fsp->inode = psbuf->st_ino;
        fsp->dev = psbuf->st_dev;
        fsp->size = psbuf->st_size;
        fsp->vuid = current_user.vuid;
        fsp->file_pid = global_smbpid;
        fsp->can_lock = True;
        fsp->can_read = False;
        fsp->can_write = False;
        fsp->share_mode = share_mode;
        fsp->desired_access = desired_access;
        fsp->print_file = False;
        fsp->modified = False;
        fsp->oplock_type = NO_OPLOCK;
        fsp->sent_oplock_break = NO_BREAK_SENT;
        fsp->is_directory = True;
        fsp->is_stat = False;
        fsp->directory_delete_on_close = False;
        string_set(&fsp->fsp_name,fname);

        if (delete_on_close) {
                NTSTATUS status = set_delete_on_close_internal(fsp, delete_on_close, 0);

                if (!NT_STATUS_IS_OK(status)) {
                        file_free(fsp);
                        return NULL;
                }
        }

        /* Change the owner if required. */
        if ((*action == FILE_WAS_CREATED) && lp_inherit_owner(SNUM(conn))) {
                change_owner_to_parent(conn, fsp, fsp->fsp_name, psbuf);
        }

        conn->num_files_open++;

        return fsp;
}

/****************************************************************************
 Open a pseudo-file (no locking checks - a 'stat' open).
****************************************************************************/

files_struct *open_file_stat(connection_struct *conn, char *fname, SMB_STRUCT_STAT *psbuf)
{
        extern struct current_user current_user;
        files_struct *fsp = NULL;

        if (!VALID_STAT(*psbuf))
                return NULL;

        /* Can't 'stat' open directories. */
        if(S_ISDIR(psbuf->st_mode))
                return NULL;

        fsp = file_new(conn);
        if(!fsp)
                return NULL;

        DEBUG(5,("open_file_stat: 'opening' file %s\n", fname));

        /*
         * Setup the files_struct for it.
         */
        
        fsp->mode = psbuf->st_mode;
        fsp->inode = psbuf->st_ino;
        fsp->dev = psbuf->st_dev;
        fsp->size = psbuf->st_size;
        fsp->vuid = current_user.vuid;
        fsp->file_pid = global_smbpid;
        fsp->can_lock = False;
        fsp->can_read = False;
        fsp->can_write = False;
        fsp->share_mode = 0;
        fsp->desired_access = 0;
        fsp->print_file = False;
        fsp->modified = False;
        fsp->oplock_type = NO_OPLOCK;
        fsp->sent_oplock_break = NO_BREAK_SENT;
        fsp->is_directory = False;
        fsp->is_stat = True;
        fsp->directory_delete_on_close = False;
        string_set(&fsp->fsp_name,fname);

        conn->num_files_open++;

        return fsp;
}