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samba-mirror/source3/smbd/open.c
Jeremy Allison 88b55f47b4 Move from timestamp to gen count file id's for finding oplocked files 
in a tdb.
Jeremy.
(This used to be commit 058ae6b58f)
2001-10-20 21:59:34 +00:00

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/*
Unix SMB/Netbios implementation.
Version 1.9.
file opening and share modes
Copyright (C) Andrew Tridgell 1992-1998
Copyright (C) Jeremy Allison 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"
extern userdom_struct current_user_info;
extern uint16 global_oplock_port;
extern BOOL global_client_failed_oplock_break;
/****************************************************************************
fd support routines - attempt to do a dos_open.
****************************************************************************/
static int fd_open(struct connection_struct *conn, char *fname,
int flags, mode_t mode)
{
int fd;
#ifdef O_NONBLOCK
flags |= O_NONBLOCK;
#endif
fd = conn->vfs_ops.open(conn,fname,flags,mode);
/* Fix for files ending in '.' */
if((fd == -1) && (errno == ENOENT) &&
(strchr_m(fname,'.')==NULL)) {
pstrcat(fname,".");
fd = conn->vfs_ops.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 -1;
return fd_close_posix(conn, fsp);
}
/****************************************************************************
Check a filename for the pipe string.
****************************************************************************/
static void check_for_pipe(char *fname)
{
/* special case of pipe opens */
char s[10];
StrnCpy(s,fname,sizeof(s)-1);
strlower(s);
if (strstr(s,"pipe/")) {
DEBUG(3,("Rejecting named pipe open for %s\n",fname));
unix_ERR_class = ERRSRV;
unix_ERR_code = ERRaccess;
}
}
/****************************************************************************
Open a file.
****************************************************************************/
static BOOL open_file(files_struct *fsp,connection_struct *conn,
char *fname1,SMB_STRUCT_STAT *psbuf,int flags,mode_t mode)
{
extern struct current_user current_user;
pstring fname;
int accmode = (flags & O_ACCMODE);
int local_flags = flags;
fsp->fd = -1;
fsp->oplock_type = NO_OPLOCK;
errno = EPERM;
pstrcpy(fname,fname1);
/* 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;
}
}
/*
* 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))
local_flags = (flags & ~O_ACCMODE)|O_RDWR;
/*
* 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;
/* 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;
}
if (!VALID_STAT(*psbuf)) {
if (vfs_fstat(fsp,fsp->fd,psbuf) == -1) {
DEBUG(0,("Error doing fstat on open file %s (%s)\n", fname,strerror(errno) ));
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->size = psbuf->st_size;
fsp->pos = -1;
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->print_file = False;
fsp->modified = False;
fsp->oplock_type = NO_OPLOCK;
fsp->sent_oplock_break = NO_BREAK_SENT;
fsp->is_directory = False;
fsp->stat_open = False;
fsp->directory_delete_on_close = False;
fsp->conn = conn;
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));
/*
* Take care of inherited ACLs on created files. JRA.
*/
if ((flags & O_CREAT) && (conn->vfs_ops.fchmod_acl != NULL)) {
int saved_errno = errno; /* We might get ENOSYS in the next call.. */
if (conn->vfs_ops.fchmod_acl(fsp, fsp->fd, mode) == -1 && errno == ENOSYS)
errno = saved_errno; /* Ignore ENOSYS */
}
return True;
}
/****************************************************************************
C. Hoch 11/22/95
Helper for open_file_shared.
Truncate a file after checking locking; close file if locked.
**************************************************************************/
static int truncate_unless_locked(struct connection_struct *conn, files_struct *fsp)
{
SMB_BIG_UINT mask = (SMB_BIG_UINT)-1;
if (is_locked(fsp,fsp->conn,mask,0,WRITE_LOCK,True)){
errno = EACCES;
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRlock;
return -1;
} else {
return conn->vfs_ops.ftruncate(fsp,fsp->fd,0);
}
}
/*******************************************************************
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 int check_share_mode( share_mode_entry *share, int share_mode,
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);
/*
* 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 ));
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRnoaccess;
return False;
}
/*
* If delete access was requested and the existing share mode doesn't have
* ALLOW_SHARE_DELETE then deny.
*/
if (GET_DELETE_ACCESS_REQUESTED(share_mode) && !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 ));
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRbadshare;
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 (GET_DELETE_ACCESS_REQUESTED(share->share_mode) && !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 ));
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRbadshare;
return False;
}
{
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));
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRbadshare;
return False;
}
if (access_allowed == AREAD)
*flags = O_RDONLY;
if (access_allowed == AWRITE)
*flags = O_WRONLY;
}
return True;
}
/****************************************************************************
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, 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 = 0;
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)
return 0;
/*
* Check if the share modes will give us access.
*/
do {
share_mode_entry broken_entry;
broke_oplock = False;
*p_all_current_opens_are_level_II = True;
for(i = 0; i < num_share_modes; i++) {
share_mode_entry *share_entry = &old_shares[i];
/*
* 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.
*/
if((*p_oplock_request && EXCLUSIVE_OPLOCK_TYPE(share_entry->op_type)) ||
(!*p_oplock_request && (share_entry->op_type != NO_OPLOCK))) {
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));
/* 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);
errno = EACCES;
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRbadshare;
return -1;
}
broke_oplock = True;
broken_entry = *share_entry;
break;
} else if (!LEVEL_II_OPLOCK_TYPE(share_entry->op_type)) {
*p_all_current_opens_are_level_II = False;
}
/* someone else has a share lock on it, check to see
if we can too */
if(check_share_mode(share_entry, share_mode, fname, fcbopen, p_flags) == False) {
SAFE_FREE(old_shares);
errno = EACCES;
return -1;
}
} /* end for */
if(broke_oplock) {
SAFE_FREE(old_shares);
num_share_modes = get_share_modes(conn, dev, inode, &old_shares);
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, 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.pid, fname, (unsigned int)dev, (double)inode));
if (process_exists(broken_entry.pid)) {
pstring errmsg;
slprintf(errmsg, sizeof(errmsg)-1,
"open_mode_check: Existant process %d left active oplock.\n",
broken_entry.pid );
smb_panic(errmsg);
}
if (del_share_entry(dev, inode, &broken_entry, NULL) == -1) {
errno = EACCES;
unix_ERR_class = ERRDOS;
unix_ERR_code = ERRbadshare;
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 if broke_oplock */
} while(broke_oplock);
if(old_shares != 0)
SAFE_FREE(old_shares);
/*
* 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 ));
}
return num_share_modes;
}
/****************************************************************************
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
;;
}
/****************************************************************************
Open a file with a share mode. On output from this open we are guarenteeing
that
****************************************************************************/
files_struct *open_file_shared(connection_struct *conn,char *fname, SMB_STRUCT_STAT *psbuf,
int share_mode,int ofun, mode_t mode,int oplock_request,
int *Access,int *action)
{
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_access_requested = GET_DELETE_ACCESS_REQUESTED(share_mode);
BOOL file_existed = VALID_STAT(*psbuf);
BOOL fcbopen = 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;
if (conn->printer) {
/* printers are handled completely differently. Most of the passed parameters are
ignored */
*Access = DOS_OPEN_WRONLY;
*action = FILE_WAS_CREATED;
return print_fsp_open(conn);
}
fsp = file_new(conn);
if(!fsp)
return NULL;
DEBUG(10,("open_file_shared: fname = %s, share_mode = %x, ofun = %x, mode = %o, oplock request = %d\n",
fname, share_mode, ofun, (int)mode, oplock_request ));
if (!check_name(fname,conn)) {
file_free(fsp);
return NULL;
}
/* 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 EAs - try and say we don't support them */
if (strstr(fname,".+,;=[].")) {
unix_ERR_class = ERRDOS;
/* OS/2 Workplace shell fix may be main code stream in a later release. */
#if 1 /* OS2_WPS_FIX - Recent versions of OS/2 need this. */
unix_ERR_code = ERRcannotopen;
#else /* OS2_WPS_FIX */
unix_ERR_code = ERROR_EAS_NOT_SUPPORTED;
#endif /* OS2_WPS_FIX */
DEBUG(5,("open_file_shared: OS/2 EA's are not supported.\n"));
file_free(fsp);
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 ));
file_free(fsp);
errno = EEXIST;
return NULL;
}
if (GET_FILE_CREATE_DISPOSITION(ofun) == FILE_CREATE_IF_NOT_EXIST)
flags2 |= O_CREAT;
if (GET_FILE_OPEN_DISPOSITION(ofun) == FILE_EXISTS_TRUNCATE)
flags2 |= O_TRUNC;
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_WRONLY:
flags = O_WRONLY;
break;
case DOS_OPEN_FCB:
fcbopen = True;
flags = O_RDWR;
break;
case DOS_OPEN_RDWR:
flags = O_RDWR;
break;
default:
flags = O_RDONLY;
break;
}
#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(dos_mode(conn,fname,psbuf)))) {
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" ));
file_free(fsp);
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));
file_free(fsp);
errno = EINVAL;
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, 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.
*/
fsp_open = open_file(fsp,conn,fname,psbuf,flags|(flags2&~(O_TRUNC|O_CREAT)),mode);
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 ));
unlock_share_entry(conn, dev, inode);
if (fsp_open)
fd_close(conn, fsp);
file_free(fsp);
return NULL;
}
/*
* We exit this block with the share entry *locked*.....
*/
}
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);
if (!fsp_open && (flags == O_RDWR) && (errno != ENOENT) && fcbopen) {
if((fsp_open = open_file(fsp,conn,fname,psbuf,O_RDONLY,mode)) == 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) {
lock_share_entry_fsp(fsp);
num_share_modes = open_mode_check(conn, fname, dev, inode, share_mode,
&flags, &oplock_request, &all_current_opens_are_level_II);
if(num_share_modes == -1) {
unlock_share_entry_fsp(fsp);
fd_close(conn,fsp);
file_free(fsp);
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 ((truncate_unless_locked(conn,fsp) == -1) || (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) |
SET_DELETE_ACCESS_REQUESTED(delete_access_requested);
DEBUG(10,("open_file_shared : share_mode = %x\n", fsp->share_mode ));
if (Access)
(*Access) = open_mode;
if (action) {
if (file_existed && !(flags2 & O_TRUNC))
*action = FILE_WAS_OPENED;
if (!file_existed)
*action = FILE_WAS_CREATED;
if (file_existed && (flags2 & O_TRUNC))
*action = FILE_WAS_OVERWRITTEN;
}
/*
* 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;
}
set_share_mode(fsp, port, oplock_request);
unlock_share_entry_fsp(fsp);
conn->num_files_open++;
return fsp;
}
/****************************************************************************
Open a file for permissions read only. Return a pseudo file entry
with the 'stat_open' flag set
****************************************************************************/
files_struct *open_file_stat(connection_struct *conn, char *fname,
SMB_STRUCT_STAT *psbuf, int smb_ofun, int *action)
{
extern struct current_user current_user;
files_struct *fsp = NULL;
if (!VALID_STAT(*psbuf)) {
DEBUG(0,("open_file_stat: unable to stat name = %s. Error was %s\n", fname, strerror(errno) ));
return NULL;
}
if(S_ISDIR(psbuf->st_mode)) {
DEBUG(0,("open_file_stat: %s is a directory !\n", fname ));
return NULL;
}
fsp = file_new(conn);
if(!fsp)
return NULL;
*action = FILE_WAS_OPENED;
DEBUG(5,("open_file_stat: opening file %s as a stat entry\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->pos = -1;
fsp->can_lock = False;
fsp->can_read = False;
fsp->can_write = False;
fsp->share_mode = 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->stat_open = True;
fsp->directory_delete_on_close = False;
fsp->conn = conn;
string_set(&fsp->fsp_name,fname);
fsp->wcp = NULL; /* Write cache pointer. */
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, 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;
fsp_open = open_file(fsp,conn,fname,psbuf,O_WRONLY,0);
/*
* 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, char *fname,
SMB_STRUCT_STAT *psbuf, int smb_ofun, mode_t unixmode, int *action)
{
extern struct current_user current_user;
BOOL got_stat = False;
files_struct *fsp = file_new(conn);
if(!fsp)
return NULL;
fsp->conn = conn; /* The vfs_fXXX() macros need this. */
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.
*/
if(!CAN_WRITE(conn)) {
DEBUG(2,("open_directory: failing create on read-only share\n"));
file_free(fsp);
errno = EACCES;
return NULL;
}
if(vfs_mkdir(conn,fname, unix_mode(conn,aDIR, fname)) < 0) {
DEBUG(2,("open_directory: unable to create %s. Error was %s\n",
fname, strerror(errno) ));
file_free(fsp);
return NULL;
}
if(vfs_stat(conn,fname, psbuf) != 0) {
file_free(fsp);
return NULL;
}
*action = FILE_WAS_CREATED;
}
} else {
/*
* Don't create - just check that it *was* a directory.
*/
if(!got_stat) {
DEBUG(0,("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->pos = -1;
fsp->can_lock = True;
fsp->can_read = False;
fsp->can_write = False;
fsp->share_mode = 0;
fsp->print_file = False;
fsp->modified = False;
fsp->oplock_type = NO_OPLOCK;
fsp->sent_oplock_break = NO_BREAK_SENT;
fsp->is_directory = True;
fsp->directory_delete_on_close = False;
fsp->conn = conn;
string_set(&fsp->fsp_name,fname);
conn->num_files_open++;
return fsp;
}
/*******************************************************************
Check if the share mode on a file allows it to be deleted or unlinked.
Return True if sharing doesn't prevent the operation.
********************************************************************/
BOOL check_file_sharing(connection_struct *conn,char *fname, BOOL rename_op)
{
int i;
int ret = False;
share_mode_entry *old_shares = 0;
int num_share_modes;
SMB_STRUCT_STAT sbuf;
pid_t pid = sys_getpid();
SMB_DEV_T dev;
SMB_INO_T inode;
if (vfs_stat(conn,fname,&sbuf) == -1)
return(True);
dev = sbuf.st_dev;
inode = sbuf.st_ino;
lock_share_entry(conn, dev, inode);
num_share_modes = get_share_modes(conn, dev, inode, &old_shares);
/*
* Check if the share modes will give us access.
*/
if(num_share_modes != 0)
{
BOOL broke_oplock;
do
{
broke_oplock = False;
for(i = 0; i < num_share_modes; i++)
{
share_mode_entry *share_entry = &old_shares[i];
/*
* Break oplocks before checking share modes. See comment in
* open_file_shared for details.
* Check if someone has an oplock on this file. If so we must
* break it before continuing.
*/
if(BATCH_OPLOCK_TYPE(share_entry->op_type))
{
#if 0
/* JRA. Try removing this code to see if the new oplock changes
fix the problem. I'm dubious, but Andrew is recommending we
try this....
*/
/*
* It appears that the NT redirector may have a bug, in that
* it tries to do an SMBmv on a file that it has open with a
* batch oplock, and then fails to respond to the oplock break
* request. This only seems to occur when the client is doing an
* SMBmv to the smbd it is using - thus we try and detect this
* condition by checking if the file being moved is open and oplocked by
* this smbd process, and then not sending the oplock break in this
* special case. If the file was open with a deny mode that
* prevents the move the SMBmv will fail anyway with a share
* violation error. JRA.
*/
if(rename_op && (share_entry->pid == pid))
{
DEBUG(0,("check_file_sharing: NT redirector workaround - rename attempted on \
batch oplocked file %s, dev = %x, inode = %.0f\n", fname, (unsigned int)dev, (double)inode));
/*
* This next line is a test that allows the deny-mode
* processing to be skipped. This seems to be needed as
* NT insists on the rename succeeding (in Office 9x no less !).
* This should be removed as soon as (a) MS fix the redirector
* bug or (b) NT SMB support in Samba makes NT not issue the
* call (as is my fervent hope). JRA.
*/
continue;
}
else
#endif /* 0 */
{
DEBUG(5,("check_file_sharing: breaking oplock (%x) on file %s, \
dev = %x, inode = %.0f\n", share_entry->op_type, fname, (unsigned int)dev, (double)inode));
/* Oplock break.... */
unlock_share_entry(conn, dev, inode);
if(request_oplock_break(share_entry) == False)
{
DEBUG(0,("check_file_sharing: 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);
return False;
}
lock_share_entry(conn, dev, inode);
broke_oplock = True;
break;
}
}
/*
* If this is a delete request and ALLOW_SHARE_DELETE is set then allow
* this to proceed. This takes precedence over share modes.
*/
if(!rename_op && GET_ALLOW_SHARE_DELETE(share_entry->share_mode))
continue;
/*
* Someone else has a share lock on it, check to see
* if we can too.
*/
if ((GET_DENY_MODE(share_entry->share_mode) != DENY_DOS) ||
(share_entry->pid != pid))
goto free_and_exit;
} /* end for */
if(broke_oplock)
{
SAFE_FREE(old_shares);
num_share_modes = get_share_modes(conn, dev, inode, &old_shares);
}
} while(broke_oplock);
}
/* XXXX exactly what share mode combinations should be allowed for
deleting/renaming? */
/*
* If we got here then either there were no share modes or
* all share modes were DENY_DOS and the pid == getpid() or
* delete access was requested and all share modes had the
* ALLOW_SHARE_DELETE bit set (takes precedence over other
* share modes).
*/
ret = True;
free_and_exit:
unlock_share_entry(conn, dev, inode);
SAFE_FREE(old_shares);
return(ret);
}
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