/* Unix SMB/CIFS implementation. Files[] structure handling Copyright (C) Andrew Tridgell 1998 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 3 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, see <http://www.gnu.org/licenses/>. */ #include "includes.h" static int real_max_open_files; #define VALID_FNUM(fnum) (((fnum) >= 0) && ((fnum) < real_max_open_files)) #define FILE_HANDLE_OFFSET 0x1000 static struct bitmap *file_bmap; static files_struct *Files; /* a fsp to use when chaining */ static files_struct *chain_fsp = NULL; static int files_used; /* A singleton cache to speed up searching by dev/inode. */ static struct fsp_singleton_cache { files_struct *fsp; struct file_id id; } fsp_fi_cache; /**************************************************************************** Return a unique number identifying this fsp over the life of this pid. ****************************************************************************/ static unsigned long get_gen_count(void) { static unsigned long file_gen_counter; if ((++file_gen_counter) == 0) return ++file_gen_counter; return file_gen_counter; } /**************************************************************************** Find first available file slot. ****************************************************************************/ NTSTATUS file_new(connection_struct *conn, files_struct **result) { int i; static int first_file; files_struct *fsp; /* we want to give out file handles differently on each new connection because of a common bug in MS clients where they try to reuse a file descriptor from an earlier smb connection. This code increases the chance that the errant client will get an error rather than causing corruption */ if (first_file == 0) { first_file = (sys_getpid() ^ (int)time(NULL)) % real_max_open_files; } /* TODO: Port the id-tree implementation from Samba4 */ i = bitmap_find(file_bmap, first_file); if (i == -1) { DEBUG(0,("ERROR! Out of file structures\n")); /* TODO: We have to unconditionally return a DOS error here, * W2k3 even returns ERRDOS/ERRnofids for ntcreate&x with * NTSTATUS negotiated */ return NT_STATUS_TOO_MANY_OPENED_FILES; } fsp = SMB_MALLOC_P(files_struct); if (!fsp) { return NT_STATUS_NO_MEMORY; } ZERO_STRUCTP(fsp); fsp->fh = SMB_MALLOC_P(struct fd_handle); if (!fsp->fh) { SAFE_FREE(fsp); return NT_STATUS_NO_MEMORY; } ZERO_STRUCTP(fsp->fh); fsp->fh->ref_count = 1; fsp->fh->fd = -1; fsp->conn = conn; fsp->fh->gen_id = get_gen_count(); GetTimeOfDay(&fsp->open_time); first_file = (i+1) % real_max_open_files; bitmap_set(file_bmap, i); files_used++; fsp->fnum = i + FILE_HANDLE_OFFSET; SMB_ASSERT(fsp->fnum < 65536); string_set(&fsp->fsp_name,""); DLIST_ADD(Files, fsp); DEBUG(5,("allocated file structure %d, fnum = %d (%d used)\n", i, fsp->fnum, files_used)); chain_fsp = fsp; /* A new fsp invalidates a negative fsp_fi_cache. */ if (fsp_fi_cache.fsp == NULL) { ZERO_STRUCT(fsp_fi_cache); } *result = fsp; return NT_STATUS_OK; } /**************************************************************************** Close all open files for a connection. ****************************************************************************/ void file_close_conn(connection_struct *conn) { files_struct *fsp, *next; for (fsp=Files;fsp;fsp=next) { next = fsp->next; if (fsp->conn == conn) { close_file(fsp,SHUTDOWN_CLOSE); } } } /**************************************************************************** Close all open files for a pid and a vuid. ****************************************************************************/ void file_close_pid(uint16 smbpid, int vuid) { files_struct *fsp, *next; for (fsp=Files;fsp;fsp=next) { next = fsp->next; if ((fsp->file_pid == smbpid) && (fsp->vuid == vuid)) { close_file(fsp,SHUTDOWN_CLOSE); } } } /**************************************************************************** Initialise file structures. ****************************************************************************/ #define MAX_OPEN_FUDGEFACTOR 20 void file_init(void) { int request_max_open_files = lp_max_open_files(); int real_lim; /* * Set the max_open files to be the requested * max plus a fudgefactor to allow for the extra * fd's we need such as log files etc... */ real_lim = set_maxfiles(request_max_open_files + MAX_OPEN_FUDGEFACTOR); real_max_open_files = real_lim - MAX_OPEN_FUDGEFACTOR; if (real_max_open_files + FILE_HANDLE_OFFSET + MAX_OPEN_PIPES > 65536) real_max_open_files = 65536 - FILE_HANDLE_OFFSET - MAX_OPEN_PIPES; if(real_max_open_files != request_max_open_files) { DEBUG(1,("file_init: Information only: requested %d \ open files, %d are available.\n", request_max_open_files, real_max_open_files)); } SMB_ASSERT(real_max_open_files > 100); file_bmap = bitmap_allocate(real_max_open_files); if (!file_bmap) { exit_server("out of memory in file_init"); } /* * Ensure that pipe_handle_oppset is set correctly. */ set_pipe_handle_offset(real_max_open_files); } /**************************************************************************** Close files open by a specified vuid. ****************************************************************************/ void file_close_user(int vuid) { files_struct *fsp, *next; for (fsp=Files;fsp;fsp=next) { next=fsp->next; if (fsp->vuid == vuid) { close_file(fsp,SHUTDOWN_CLOSE); } } } /**************************************************************************** Debug to enumerate all open files in the smbd. ****************************************************************************/ void file_dump_open_table(void) { int count=0; files_struct *fsp; for (fsp=Files;fsp;fsp=fsp->next,count++) { DEBUG(10,("Files[%d], fnum = %d, name %s, fd = %d, gen = %lu, fileid=%s\n", count, fsp->fnum, fsp->fsp_name, fsp->fh->fd, (unsigned long)fsp->fh->gen_id, file_id_string_tos(&fsp->file_id))); } } /**************************************************************************** Find a fsp given a file descriptor. ****************************************************************************/ files_struct *file_find_fd(int fd) { int count=0; files_struct *fsp; for (fsp=Files;fsp;fsp=fsp->next,count++) { if (fsp->fh->fd == fd) { if (count > 10) { DLIST_PROMOTE(Files, fsp); } return fsp; } } return NULL; } /**************************************************************************** Find a fsp given a device, inode and file_id. ****************************************************************************/ files_struct *file_find_dif(struct file_id id, unsigned long gen_id) { int count=0; files_struct *fsp; for (fsp=Files;fsp;fsp=fsp->next,count++) { /* We can have a fsp->fh->fd == -1 here as it could be a stat open. */ if (file_id_equal(&fsp->file_id, &id) && fsp->fh->gen_id == gen_id ) { if (count > 10) { DLIST_PROMOTE(Files, fsp); } /* Paranoia check. */ if ((fsp->fh->fd == -1) && (fsp->oplock_type != NO_OPLOCK) && (fsp->oplock_type != FAKE_LEVEL_II_OPLOCK)) { DEBUG(0,("file_find_dif: file %s file_id = %s, gen = %u \ oplock_type = %u is a stat open with oplock type !\n", fsp->fsp_name, file_id_string_tos(&fsp->file_id), (unsigned int)fsp->fh->gen_id, (unsigned int)fsp->oplock_type )); smb_panic("file_find_dif"); } return fsp; } } return NULL; } /**************************************************************************** Check if an fsp still exists. ****************************************************************************/ files_struct *file_find_fsp(files_struct *orig_fsp) { files_struct *fsp; for (fsp=Files;fsp;fsp=fsp->next) { if (fsp == orig_fsp) return fsp; } return NULL; } /**************************************************************************** Find the first fsp given a device and inode. We use a singleton cache here to speed up searching from getfilepathinfo calls. ****************************************************************************/ files_struct *file_find_di_first(struct file_id id) { files_struct *fsp; if (file_id_equal(&fsp_fi_cache.id, &id)) { /* Positive or negative cache hit. */ return fsp_fi_cache.fsp; } fsp_fi_cache.id = id; for (fsp=Files;fsp;fsp=fsp->next) { if ( fsp->fh->fd != -1 && file_id_equal(&fsp->file_id, &id)) { /* Setup positive cache. */ fsp_fi_cache.fsp = fsp; return fsp; } } /* Setup negative cache. */ fsp_fi_cache.fsp = NULL; return NULL; } /**************************************************************************** Find the next fsp having the same device and inode. ****************************************************************************/ files_struct *file_find_di_next(files_struct *start_fsp) { files_struct *fsp; for (fsp = start_fsp->next;fsp;fsp=fsp->next) { if ( fsp->fh->fd != -1 && file_id_equal(&fsp->file_id, &start_fsp->file_id)) { return fsp; } } return NULL; } /**************************************************************************** Find a fsp that is open for printing. ****************************************************************************/ files_struct *file_find_print(void) { files_struct *fsp; for (fsp=Files;fsp;fsp=fsp->next) { if (fsp->print_file) { return fsp; } } return NULL; } /**************************************************************************** Sync open files on a connection. ****************************************************************************/ void file_sync_all(connection_struct *conn) { files_struct *fsp, *next; for (fsp=Files;fsp;fsp=next) { next=fsp->next; if ((conn == fsp->conn) && (fsp->fh->fd != -1)) { sync_file(conn, fsp, True /* write through */); } } } /**************************************************************************** Free up a fsp. ****************************************************************************/ void file_free(files_struct *fsp) { DLIST_REMOVE(Files, fsp); string_free(&fsp->fsp_name); if (fsp->fake_file_handle) { destroy_fake_file_handle(&fsp->fake_file_handle); } if (fsp->fh->ref_count == 1) { SAFE_FREE(fsp->fh); } else { fsp->fh->ref_count--; } if (fsp->notify) { notify_remove(fsp->conn->notify_ctx, fsp); TALLOC_FREE(fsp->notify); } /* Ensure this event will never fire. */ TALLOC_FREE(fsp->oplock_timeout); /* Ensure this event will never fire. */ TALLOC_FREE(fsp->update_write_time_event); bitmap_clear(file_bmap, fsp->fnum - FILE_HANDLE_OFFSET); files_used--; DEBUG(5,("freed files structure %d (%d used)\n", fsp->fnum, files_used)); /* this is paranoia, just in case someone tries to reuse the information */ ZERO_STRUCTP(fsp); if (fsp == chain_fsp) { chain_fsp = NULL; } /* Closing a file can invalidate the positive cache. */ if (fsp == fsp_fi_cache.fsp) { ZERO_STRUCT(fsp_fi_cache); } /* Drop all remaining extensions. */ while (fsp->vfs_extension) { vfs_remove_fsp_extension(fsp->vfs_extension->owner, fsp); } SAFE_FREE(fsp); } /**************************************************************************** Get an fsp from a 16 bit fnum. ****************************************************************************/ files_struct *file_fnum(uint16 fnum) { files_struct *fsp; int count=0; for (fsp=Files;fsp;fsp=fsp->next, count++) { if (fsp->fnum == fnum) { if (count > 10) { DLIST_PROMOTE(Files, fsp); } return fsp; } } return NULL; } /**************************************************************************** Get an fsp from a packet given the offset of a 16 bit fnum. ****************************************************************************/ files_struct *file_fsp(uint16 fid) { files_struct *fsp; if (chain_fsp) { return chain_fsp; } fsp = file_fnum(fid); if (fsp) { chain_fsp = fsp; } return fsp; } /**************************************************************************** Reset the chained fsp - done at the start of a packet reply. ****************************************************************************/ void file_chain_reset(void) { chain_fsp = NULL; } /**************************************************************************** Duplicate the file handle part for a DOS or FCB open. ****************************************************************************/ NTSTATUS dup_file_fsp(files_struct *fsp, uint32 access_mask, uint32 share_access, uint32 create_options, files_struct **result) { NTSTATUS status; files_struct *dup_fsp; status = file_new(fsp->conn, &dup_fsp); if (!NT_STATUS_IS_OK(status)) { return status; } SAFE_FREE(dup_fsp->fh); dup_fsp->fh = fsp->fh; dup_fsp->fh->ref_count++; dup_fsp->file_id = fsp->file_id; dup_fsp->initial_allocation_size = fsp->initial_allocation_size; dup_fsp->mode = fsp->mode; dup_fsp->file_pid = fsp->file_pid; dup_fsp->vuid = fsp->vuid; dup_fsp->open_time = fsp->open_time; dup_fsp->access_mask = access_mask; dup_fsp->share_access = share_access; dup_fsp->oplock_type = fsp->oplock_type; dup_fsp->can_lock = fsp->can_lock; dup_fsp->can_read = (access_mask & (FILE_READ_DATA)) ? True : False; if (!CAN_WRITE(fsp->conn)) { dup_fsp->can_write = False; } else { dup_fsp->can_write = (access_mask & (FILE_WRITE_DATA | FILE_APPEND_DATA)) ? True : False; } dup_fsp->print_file = fsp->print_file; dup_fsp->modified = fsp->modified; dup_fsp->is_directory = fsp->is_directory; dup_fsp->is_stat = fsp->is_stat; dup_fsp->aio_write_behind = fsp->aio_write_behind; string_set(&dup_fsp->fsp_name,fsp->fsp_name); *result = dup_fsp; return NT_STATUS_OK; }