source/include/vfs.h

   1 /*
   2    Unix SMB/CIFS implementation.
   3    VFS structures and parameters
   4    Copyright (C) Tim Potter                             1999
   5    Copyright (C) Alexander Bokovoy                      2002
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20
  21    This work was sponsored by Optifacio Software Services, Inc.
  22 */
  23
  24 #ifndef _VFS_H
  25 #define _VFS_H
  26
  27 /* Avoid conflict with an AIX include file */
  28
  29 #ifdef vfs_ops
  30 #undef vfs_ops
  31 #endif
  32
  33 /*
  34  * As we're now (thanks Andrew ! :-) using file_structs and connection
  35  * structs in the vfs - then anyone writing a vfs must include includes.h...
  36  */
  37
  38 /*
  39  * This next constant specifies the version number of the VFS interface
  40  * this smbd will load. Increment this if *ANY* changes are made to the
  41  * vfs_ops below. JRA.
  42  */
  43
  44 /* Changed to version 2 for CIFS UNIX extensions (mknod and link added). JRA. */
  45 /* Changed to version 3 for POSIX acl extensions. JRA. */
  46 /* Changed to version 4 for cascaded VFS interface. Alexander Bokovoy. */
  47 /* Changed to version 5 for sendfile addition. JRA. */
  48 #define SMB_VFS_INTERFACE_VERSION 5
  49
  50
  51 /* Version of supported cascaded interface backward compatibility.
  52    (version 5 corresponds to SMB_VFS_INTERFACE_VERSION 5)
  53    It is used in vfs_init_custom() to detect VFS modules which conform to cascaded
  54    VFS interface but implement elder version than current version of Samba uses.
  55    This allows to use old modules with new VFS interface as far as combined VFS operation
  56    set is coherent (will be in most cases).
  57 */
  58 #define SMB_VFS_INTERFACE_CASCADED 5
  59
  60 /*
  61     Each VFS module must provide following global functions:
  62     vfs_init    -- initialization function
  63     vfs_done    -- finalization function
  64
  65     vfs_init must return proper initialized vfs_op_tuple[] array
  66     which describes all operations this module claims to intercept. This function
  67     is called whenever module is loaded into smbd process using sys_dlopen().
  68
  69     vfs_init must store somewhere vfs_handle reference if module wants to store per-instance
  70     private information for further usage. vfs_handle->data should be used to
  71     store such information. Do not try to change other fields in this structure
  72     or results likely to be unpredictable.
  73
  74     vfs_done must perform finalization of the module. In particular,
  75     this function must free vfs_ops structure returned to module from smb_vfs_get_opaque_ops()
  76     function if it is used (see below). This function is called whenever module
  77     is unloaded from smbd process using sys_dlclose().
  78
  79     Prototypes:
  80     vfs_op_tuple *vfs_init(const struct vfs_ops *def_vfs_ops,
  81                             struct smb_vfs_handle_struct *vfs_handle);
  82     void          vfs_done(connection_struct *conn);
  83
  84     All intercepted VFS operations must be declared as static functions inside module source
  85     in order to keep smbd namespace unpolluted. See source of skel, audit, and recycle bin
  86     example VFS modules for more details.
  87
  88 */
  89
  90 /* VFS operations structure */
  91
  92 struct connection_struct;
  93 struct files_struct;
  94 struct security_descriptor_info;
  95
  96 struct vfs_ops {
  97
  98         /* Disk operations */
  99
 100         int (*connect)(struct connection_struct *conn, const char *service, const char *user);
 101         void (*disconnect)(struct connection_struct *conn);
 102         SMB_BIG_UINT (*disk_free)(struct connection_struct *conn, const char *path, BOOL small_query, SMB_BIG_UINT *bsize,
 103                 SMB_BIG_UINT *dfree, SMB_BIG_UINT *dsize);
 104
 105         /* Directory operations */
 106
 107         DIR *(*opendir)(struct connection_struct *conn, const char *fname);
 108         struct dirent *(*readdir)(struct connection_struct *conn, DIR *dirp);
 109         int (*mkdir)(struct connection_struct *conn, const char *path, mode_t mode);
 110         int (*rmdir)(struct connection_struct *conn, const char *path);
 111         int (*closedir)(struct connection_struct *conn, DIR *dir);
 112
 113         /* File operations */
 114
 115         int (*open)(struct connection_struct *conn, const char *fname, int flags, mode_t mode);
 116         int (*close)(struct files_struct *fsp, int fd);
 117         ssize_t (*read)(struct files_struct *fsp, int fd, void *data, size_t n);
 118         ssize_t (*write)(struct files_struct *fsp, int fd, const void *data, size_t n);
 119         SMB_OFF_T (*lseek)(struct files_struct *fsp, int filedes, SMB_OFF_T offset, int whence);
 120         ssize_t (*sendfile)(int tofd, files_struct *fsp, int fromfd, const DATA_BLOB *header, SMB_OFF_T offset, size_t count);
 121         int (*rename)(struct connection_struct *conn, const char *old, const char *new);
 122         int (*fsync)(struct files_struct *fsp, int fd);
 123         int (*stat)(struct connection_struct *conn, const char *fname, SMB_STRUCT_STAT *sbuf);
 124         int (*fstat)(struct files_struct *fsp, int fd, SMB_STRUCT_STAT *sbuf);
 125         int (*lstat)(struct connection_struct *conn, const char *path, SMB_STRUCT_STAT *sbuf);
 126         int (*unlink)(struct connection_struct *conn, const char *path);
 127         int (*chmod)(struct connection_struct *conn, const char *path, mode_t mode);
 128         int (*fchmod)(struct files_struct *fsp, int fd, mode_t mode);
 129         int (*chown)(struct connection_struct *conn, const char *path, uid_t uid, gid_t gid);
 130         int (*fchown)(struct files_struct *fsp, int fd, uid_t uid, gid_t gid);
 131         int (*chdir)(struct connection_struct *conn, const char *path);
 132         char *(*getwd)(struct connection_struct *conn, char *buf);
 133         int (*utime)(struct connection_struct *conn, const char *path, struct utimbuf *times);
 134         int (*ftruncate)(struct files_struct *fsp, int fd, SMB_OFF_T offset);
 135         BOOL (*lock)(struct files_struct *fsp, int fd, int op, SMB_OFF_T offset, SMB_OFF_T count, int type);
 136         int (*symlink)(struct connection_struct *conn, const char *oldpath, const char *newpath);
 137         int (*readlink)(struct connection_struct *conn, const char *path, char *buf, size_t bufsiz);
 138         int (*link)(struct connection_struct *conn, const char *oldpath, const char *newpath);
 139         int (*mknod)(struct connection_struct *conn, const char *path, mode_t mode, SMB_DEV_T dev);
 140         char *(*realpath)(struct connection_struct *conn, const char *path, char *resolved_path);
 141
 142         /* NT ACL operations. */
 143
 144         size_t (*fget_nt_acl)(struct files_struct *fsp, int fd, struct security_descriptor_info **ppdesc);
 145         size_t (*get_nt_acl)(struct files_struct *fsp, const char *name, struct security_descriptor_info **ppdesc);
 146         BOOL (*fset_nt_acl)(struct files_struct *fsp, int fd, uint32 security_info_sent, struct security_descriptor_info *psd);
 147         BOOL (*set_nt_acl)(struct files_struct *fsp, const char *name, uint32 security_info_sent, struct security_descriptor_info *psd);
 148
 149         /* POSIX ACL operations. */
 150
 151         int (*chmod_acl)(struct connection_struct *conn, const char *name, mode_t mode);
 152         int (*fchmod_acl)(struct files_struct *fsp, int fd, mode_t mode);
 153
 154         int (*sys_acl_get_entry)(struct connection_struct *conn, SMB_ACL_T theacl, int entry_id, SMB_ACL_ENTRY_T *entry_p);
 155         int (*sys_acl_get_tag_type)(struct connection_struct *conn, SMB_ACL_ENTRY_T entry_d, SMB_ACL_TAG_T *tag_type_p);
 156         int (*sys_acl_get_permset)(struct connection_struct *conn, SMB_ACL_ENTRY_T entry_d, SMB_ACL_PERMSET_T *permset_p);
 157         void * (*sys_acl_get_qualifier)(struct connection_struct *conn, SMB_ACL_ENTRY_T entry_d);
 158         SMB_ACL_T (*sys_acl_get_file)(struct connection_struct *conn, const char *path_p, SMB_ACL_TYPE_T type);
 159         SMB_ACL_T (*sys_acl_get_fd)(struct files_struct *fsp, int fd);
 160         int (*sys_acl_clear_perms)(struct connection_struct *conn, SMB_ACL_PERMSET_T permset);
 161         int (*sys_acl_add_perm)(struct connection_struct *conn, SMB_ACL_PERMSET_T permset, SMB_ACL_PERM_T perm);
 162         char * (*sys_acl_to_text)(struct connection_struct *conn, SMB_ACL_T theacl, ssize_t *plen);
 163         SMB_ACL_T (*sys_acl_init)(struct connection_struct *conn, int count);
 164         int (*sys_acl_create_entry)(struct connection_struct *conn, SMB_ACL_T *pacl, SMB_ACL_ENTRY_T *pentry);
 165         int (*sys_acl_set_tag_type)(struct connection_struct *conn, SMB_ACL_ENTRY_T entry, SMB_ACL_TAG_T tagtype);
 166         int (*sys_acl_set_qualifier)(struct connection_struct *conn, SMB_ACL_ENTRY_T entry, void *qual);
 167         int (*sys_acl_set_permset)(struct connection_struct *conn, SMB_ACL_ENTRY_T entry, SMB_ACL_PERMSET_T permset);
 168         int (*sys_acl_valid)(struct connection_struct *conn, SMB_ACL_T theacl );
 169         int (*sys_acl_set_file)(struct connection_struct *conn, const char *name, SMB_ACL_TYPE_T acltype, SMB_ACL_T theacl);
 170         int (*sys_acl_set_fd)(struct files_struct *fsp, int fd, SMB_ACL_T theacl);
 171         int (*sys_acl_delete_def_file)(struct connection_struct *conn, const char *path);
 172         int (*sys_acl_get_perm)(struct connection_struct *conn, SMB_ACL_PERMSET_T permset, SMB_ACL_PERM_T perm);
 173         int (*sys_acl_free_text)(struct connection_struct *conn, char *text);
 174         int (*sys_acl_free_acl)(struct connection_struct *conn, SMB_ACL_T posix_acl);
 175         int (*sys_acl_free_qualifier)(struct connection_struct *conn, void *qualifier, SMB_ACL_TAG_T tagtype);
 176 };
 177
 178 struct vfs_options {
 179     struct vfs_options *prev, *next;
 180     char *name;
 181     char *value;
 182 };
 183
 184 /*
 185     Available VFS operations. These values must be in sync with vfs_ops struct.
 186     In particular, if new operations are added to vfs_ops, appropriate constants
 187     should be added to vfs_op_type so that order of them kept same as in vfs_ops.
 188 */
 189
 190 typedef enum _vfs_op_type {
 191
 192         SMB_VFS_OP_NOOP = -1,
 193
 194         /* Disk operations */
 195
 196         SMB_VFS_OP_CONNECT = 0,
 197         SMB_VFS_OP_DISCONNECT,
 198         SMB_VFS_OP_DISK_FREE,
 199
 200         /* Directory operations */
 201
 202         SMB_VFS_OP_OPENDIR,
 203         SMB_VFS_OP_READDIR,
 204         SMB_VFS_OP_MKDIR,
 205         SMB_VFS_OP_RMDIR,
 206         SMB_VFS_OP_CLOSEDIR,
 207
 208         /* File operations */
 209
 210         SMB_VFS_OP_OPEN,
 211         SMB_VFS_OP_CLOSE,
 212         SMB_VFS_OP_READ,
 213         SMB_VFS_OP_WRITE,
 214         SMB_VFS_OP_LSEEK,
 215         SMB_VFS_OP_SENDFILE,
 216         SMB_VFS_OP_RENAME,
 217         SMB_VFS_OP_FSYNC,
 218         SMB_VFS_OP_STAT,
 219         SMB_VFS_OP_FSTAT,
 220         SMB_VFS_OP_LSTAT,
 221         SMB_VFS_OP_UNLINK,
 222         SMB_VFS_OP_CHMOD,
 223         SMB_VFS_OP_FCHMOD,
 224         SMB_VFS_OP_CHOWN,
 225         SMB_VFS_OP_FCHOWN,
 226         SMB_VFS_OP_CHDIR,
 227         SMB_VFS_OP_GETWD,
 228         SMB_VFS_OP_UTIME,
 229         SMB_VFS_OP_FTRUNCATE,
 230         SMB_VFS_OP_LOCK,
 231         SMB_VFS_OP_SYMLINK,
 232         SMB_VFS_OP_READLINK,
 233         SMB_VFS_OP_LINK,
 234         SMB_VFS_OP_MKNOD,
 235         SMB_VFS_OP_REALPATH,
 236
 237         /* NT ACL operations. */
 238
 239         SMB_VFS_OP_FGET_NT_ACL,
 240         SMB_VFS_OP_GET_NT_ACL,
 241         SMB_VFS_OP_FSET_NT_ACL,
 242         SMB_VFS_OP_SET_NT_ACL,
 243
 244         /* POSIX ACL operations. */
 245
 246         SMB_VFS_OP_CHMOD_ACL,
 247         SMB_VFS_OP_FCHMOD_ACL,
 248
 249         SMB_VFS_OP_SYS_ACL_GET_ENTRY,
 250         SMB_VFS_OP_SYS_ACL_GET_TAG_TYPE,
 251         SMB_VFS_OP_SYS_ACL_GET_PERMSET,
 252         SMB_VFS_OP_SYS_ACL_GET_QUALIFIER,
 253         SMB_VFS_OP_SYS_ACL_GET_FILE,
 254         SMB_VFS_OP_SYS_ACL_GET_FD,
 255         SMB_VFS_OP_SYS_ACL_CLEAR_PERMS,
 256         SMB_VFS_OP_SYS_ACL_ADD_PERM,
 257         SMB_VFS_OP_SYS_ACL_TO_TEXT,
 258         SMB_VFS_OP_SYS_ACL_INIT,
 259         SMB_VFS_OP_SYS_ACL_CREATE_ENTRY,
 260         SMB_VFS_OP_SYS_ACL_SET_TAG_TYPE,
 261         SMB_VFS_OP_SYS_ACL_SET_QUALIFIER,
 262         SMB_VFS_OP_SYS_ACL_SET_PERMSET,
 263         SMB_VFS_OP_SYS_ACL_VALID,
 264         SMB_VFS_OP_SYS_ACL_SET_FILE,
 265         SMB_VFS_OP_SYS_ACL_SET_FD,
 266         SMB_VFS_OP_SYS_ACL_DELETE_DEF_FILE,
 267         SMB_VFS_OP_SYS_ACL_GET_PERM,
 268         SMB_VFS_OP_SYS_ACL_FREE_TEXT,
 269         SMB_VFS_OP_SYS_ACL_FREE_ACL,
 270         SMB_VFS_OP_SYS_ACL_FREE_QUALIFIER,
 271
 272         /* This should always be last enum value */
 273
 274         SMB_VFS_OP_LAST
 275 } vfs_op_type;
 276
 277 /*
 278     Possible VFS operation layers (per-operation)
 279
 280     These values are used by VFS subsystem when building vfs_ops for connection
 281     from multiple VFS modules. Internally, Samba differentiates only opaque and
 282     transparent layers at this process. Other types are used for providing better
 283     diagnosing facilities.
 284
 285     Most modules will provide transparent layers. Opaque layer is for modules
 286     which implement actual file system calls (like DB-based VFS). For example,
 287     default POSIX VFS which is built in into Samba is an opaque VFS module.
 288
 289     Other layer types (audit, splitter, scanner) were designed to provide different
 290     degree of transparency and for diagnosing VFS module behaviour.
 291
 292     Each module can implement several layers at the same time provided that only
 293     one layer is used per each operation.
 294
 295 */
 296
 297 typedef enum _vfs_op_layer {
 298         SMB_VFS_LAYER_NOOP = -1,        /* - For using in VFS module to indicate end of array */
 299                                         /*   of operations description */
 300         SMB_VFS_LAYER_OPAQUE = 0,       /* - Final level, does not call anything beyond itself */
 301         SMB_VFS_LAYER_TRANSPARENT,      /* - Normal operation, calls underlying layer after */
 302                                         /*   possibly changing passed data */
 303         SMB_VFS_LAYER_LOGGER,           /* - Logs data, calls underlying layer, logging does not */
 304                                         /*   use Samba VFS */
 305         SMB_VFS_LAYER_SPLITTER,         /* - Splits operation, calls underlying layer _and_ own facility, */
 306                                         /*   then combines result */
 307         SMB_VFS_LAYER_SCANNER           /* - Checks data and possibly initiates additional */
 308                                         /*   file activity like logging to files _inside_ samba VFS */
 309 } vfs_op_layer;
 310
 311 /*
 312     VFS operation description. Each VFS module initialization function returns to VFS subsystem
 313     an array of vfs_op_tuple which describes all operations this module is willing to intercept.
 314     VFS subsystem initializes then vfs_ops using this information and passes it
 315     to next VFS module as underlying vfs_ops and to connection after all VFS modules are initialized.
 316 */
 317
 318 typedef struct _vfs_op_tuple {
 319         void* op;
 320         vfs_op_type type;
 321         vfs_op_layer layer;
 322 } vfs_op_tuple;
 323
 324 /*
 325     Return vfs_ops filled with current opaque VFS operations. This function is designed to
 326     be called from VFS module initialization function for those modules which needs 'direct' VFS
 327     access (loggers or initiators of file operations other than connection asks for).
 328
 329     Returned vfs_ops must be cleaned up in VFS module's finalizer function (vfs_done_<module_name>)
 330     using safe_free().
 331
 332     Prototype:
 333     struct vfs_ops *smb_vfs_get_opaque_ops();
 334
 335     This prototype will be available via include/proto.h
 336 */
 337
 338 #endif /* _VFS_H */