fs/cifs/xattr.c

   1 /*
   2  *   fs/cifs/xattr.c
   3  *
   4  *   Copyright (c) International Business Machines  Corp., 2003, 2007
   5  *   Author(s): Steve French (sfrench@us.ibm.com)
   6  *
   7  *   This library is free software; you can redistribute it and/or modify
   8  *   it under the terms of the GNU Lesser General Public License as published
   9  *   by the Free Software Foundation; either version 2.1 of the License, or
  10  *   (at your option) any later version.
  11  *
  12  *   This library 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
  15  *   the GNU Lesser General Public License for more details.
  16  *
  17  *   You should have received a copy of the GNU Lesser General Public License
  18  *   along with this library; if not, write to the Free Software
  19  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  */
  21
  22 #include <linux/fs.h>
  23 #include <linux/posix_acl_xattr.h>
  24 #include "cifsfs.h"
  25 #include "cifspdu.h"
  26 #include "cifsglob.h"
  27 #include "cifsproto.h"
  28 #include "cifs_debug.h"
  29
  30 #define MAX_EA_VALUE_SIZE 65535
  31 #define CIFS_XATTR_DOS_ATTRIB "user.DosAttrib"
  32 #define CIFS_XATTR_USER_PREFIX "user."
  33 #define CIFS_XATTR_SYSTEM_PREFIX "system."
  34 #define CIFS_XATTR_OS2_PREFIX "os2."
  35 #define CIFS_XATTR_SECURITY_PREFIX ".security"
  36 #define CIFS_XATTR_TRUSTED_PREFIX "trusted."
  37 #define XATTR_TRUSTED_PREFIX_LEN  8
  38 #define XATTR_SECURITY_PREFIX_LEN 9
  39 /* BB need to add server (Samba e.g) support for security and trusted prefix */
  40
  41
  42
  43 int cifs_removexattr(struct dentry *direntry, const char *ea_name)
  44 {
  45         int rc = -EOPNOTSUPP;
  46 #ifdef CONFIG_CIFS_XATTR
  47         int xid;
  48         struct cifs_sb_info *cifs_sb;
  49         struct cifsTconInfo *pTcon;
  50         struct super_block *sb;
  51         char *full_path;
  52
  53         if (direntry == NULL)
  54                 return -EIO;
  55         if (direntry->d_inode == NULL)
  56                 return -EIO;
  57         sb = direntry->d_inode->i_sb;
  58         if (sb == NULL)
  59                 return -EIO;
  60         xid = GetXid();
  61
  62         cifs_sb = CIFS_SB(sb);
  63         pTcon = cifs_sb->tcon;
  64
  65         full_path = build_path_from_dentry(direntry);
  66         if (full_path == NULL) {
  67                 FreeXid(xid);
  68                 return -ENOMEM;
  69         }
  70         if (ea_name == NULL) {
  71                 cFYI(1, ("Null xattr names not supported"));
  72         } else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5)
  73                 && (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4))) {
  74                 cFYI(1,
  75                     ("illegal xattr request %s (only user namespace supported)",
  76                         ea_name));
  77                 /* BB what if no namespace prefix? */
  78                 /* Should we just pass them to server, except for
  79                 system and perhaps security prefixes? */
  80         } else {
  81                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
  82                         goto remove_ea_exit;
  83
  84                 ea_name += 5; /* skip past user. prefix */
  85                 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, NULL,
  86                         (__u16)0, cifs_sb->local_nls,
  87                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
  88         }
  89 remove_ea_exit:
  90         kfree(full_path);
  91         FreeXid(xid);
  92 #endif
  93         return rc;
  94 }
  95
  96 int cifs_setxattr(struct dentry *direntry, const char *ea_name,
  97                   const void *ea_value, size_t value_size, int flags)
  98 {
  99         int rc = -EOPNOTSUPP;
 100 #ifdef CONFIG_CIFS_XATTR
 101         int xid;
 102         struct cifs_sb_info *cifs_sb;
 103         struct cifsTconInfo *pTcon;
 104         struct super_block *sb;
 105         char *full_path;
 106
 107         if (direntry == NULL)
 108                 return -EIO;
 109         if (direntry->d_inode == NULL)
 110                 return -EIO;
 111         sb = direntry->d_inode->i_sb;
 112         if (sb == NULL)
 113                 return -EIO;
 114         xid = GetXid();
 115
 116         cifs_sb = CIFS_SB(sb);
 117         pTcon = cifs_sb->tcon;
 118
 119         full_path = build_path_from_dentry(direntry);
 120         if (full_path == NULL) {
 121                 FreeXid(xid);
 122                 return -ENOMEM;
 123         }
 124         /* return dos attributes as pseudo xattr */
 125         /* return alt name if available as pseudo attr */
 126
 127         /* if proc/fs/cifs/streamstoxattr is set then
 128                 search server for EAs or streams to
 129                 returns as xattrs */
 130         if (value_size > MAX_EA_VALUE_SIZE) {
 131                 cFYI(1, ("size of EA value too large"));
 132                 kfree(full_path);
 133                 FreeXid(xid);
 134                 return -EOPNOTSUPP;
 135         }
 136
 137         if (ea_name == NULL) {
 138                 cFYI(1, ("Null xattr names not supported"));
 139         } else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5) == 0) {
 140                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 141                         goto set_ea_exit;
 142                 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0)
 143                         cFYI(1, ("attempt to set cifs inode metadata"));
 144
 145                 ea_name += 5; /* skip past user. prefix */
 146                 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
 147                         (__u16)value_size, cifs_sb->local_nls,
 148                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 149         } else if (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4) == 0) {
 150                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 151                         goto set_ea_exit;
 152
 153                 ea_name += 4; /* skip past os2. prefix */
 154                 rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
 155                         (__u16)value_size, cifs_sb->local_nls,
 156                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 157         } else {
 158                 int temp;
 159                 temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
 160                         strlen(POSIX_ACL_XATTR_ACCESS));
 161                 if (temp == 0) {
 162 #ifdef CONFIG_CIFS_POSIX
 163                         if (sb->s_flags & MS_POSIXACL)
 164                                 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
 165                                         ea_value, (const int)value_size,
 166                                         ACL_TYPE_ACCESS, cifs_sb->local_nls,
 167                                         cifs_sb->mnt_cifs_flags &
 168                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 169                         cFYI(1, ("set POSIX ACL rc %d", rc));
 170 #else
 171                         cFYI(1, ("set POSIX ACL not supported"));
 172 #endif
 173                 } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
 174                                    strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
 175 #ifdef CONFIG_CIFS_POSIX
 176                         if (sb->s_flags & MS_POSIXACL)
 177                                 rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
 178                                         ea_value, (const int)value_size,
 179                                         ACL_TYPE_DEFAULT, cifs_sb->local_nls,
 180                                         cifs_sb->mnt_cifs_flags &
 181                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 182                         cFYI(1, ("set POSIX default ACL rc %d", rc));
 183 #else
 184                         cFYI(1, ("set default POSIX ACL not supported"));
 185 #endif
 186                 } else {
 187                         cFYI(1, ("illegal xattr request %s (only user namespace"
 188                                  " supported)", ea_name));
 189                   /* BB what if no namespace prefix? */
 190                   /* Should we just pass them to server, except for
 191                   system and perhaps security prefixes? */
 192                 }
 193         }
 194
 195 set_ea_exit:
 196         kfree(full_path);
 197         FreeXid(xid);
 198 #endif
 199         return rc;
 200 }
 201
 202 ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
 203         void *ea_value, size_t buf_size)
 204 {
 205         ssize_t rc = -EOPNOTSUPP;
 206 #ifdef CONFIG_CIFS_XATTR
 207         int xid;
 208         struct cifs_sb_info *cifs_sb;
 209         struct cifsTconInfo *pTcon;
 210         struct super_block *sb;
 211         char *full_path;
 212
 213         if (direntry == NULL)
 214                 return -EIO;
 215         if (direntry->d_inode == NULL)
 216                 return -EIO;
 217         sb = direntry->d_inode->i_sb;
 218         if (sb == NULL)
 219                 return -EIO;
 220
 221         xid = GetXid();
 222
 223         cifs_sb = CIFS_SB(sb);
 224         pTcon = cifs_sb->tcon;
 225
 226         full_path = build_path_from_dentry(direntry);
 227         if (full_path == NULL) {
 228                 FreeXid(xid);
 229                 return -ENOMEM;
 230         }
 231         /* return dos attributes as pseudo xattr */
 232         /* return alt name if available as pseudo attr */
 233         if (ea_name == NULL) {
 234                 cFYI(1, ("Null xattr names not supported"));
 235         } else if (strncmp(ea_name, CIFS_XATTR_USER_PREFIX, 5) == 0) {
 236                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 237                         goto get_ea_exit;
 238
 239                 if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
 240                         cFYI(1, ("attempt to query cifs inode metadata"));
 241                         /* revalidate/getattr then populate from inode */
 242                 } /* BB add else when above is implemented */
 243                 ea_name += 5; /* skip past user. prefix */
 244                 rc = CIFSSMBQueryEA(xid, pTcon, full_path, ea_name, ea_value,
 245                         buf_size, cifs_sb->local_nls,
 246                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 247         } else if (strncmp(ea_name, CIFS_XATTR_OS2_PREFIX, 4) == 0) {
 248                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 249                         goto get_ea_exit;
 250
 251                 ea_name += 4; /* skip past os2. prefix */
 252                 rc = CIFSSMBQueryEA(xid, pTcon, full_path, ea_name, ea_value,
 253                         buf_size, cifs_sb->local_nls,
 254                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 255         } else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
 256                           strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
 257 #ifdef CONFIG_CIFS_POSIX
 258                 if (sb->s_flags & MS_POSIXACL)
 259                         rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
 260                                 ea_value, buf_size, ACL_TYPE_ACCESS,
 261                                 cifs_sb->local_nls,
 262                                 cifs_sb->mnt_cifs_flags &
 263                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 264 #ifdef CONFIG_CIFS_EXPERIMENTAL
 265                 else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) {
 266                         __u16 fid;
 267                         int oplock = FALSE;
 268                         struct cifs_ntsd *pacl = NULL;
 269                         __u32 buflen = 0;
 270                         if (experimEnabled)
 271                                 rc = CIFSSMBOpen(xid, pTcon, full_path,
 272                                         FILE_OPEN, GENERIC_READ, 0, &fid,
 273                                         &oplock, NULL, cifs_sb->local_nls,
 274                                         cifs_sb->mnt_cifs_flags &
 275                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 276                         /* else rc is EOPNOTSUPP from above */
 277
 278                         if (rc == 0) {
 279                                 rc = CIFSSMBGetCIFSACL(xid, pTcon, fid, &pacl,
 280                                                       &buflen);
 281                                 CIFSSMBClose(xid, pTcon, fid);
 282                         }
 283                 }
 284 #endif /* EXPERIMENTAL */
 285 #else
 286                 cFYI(1, ("query POSIX ACL not supported yet"));
 287 #endif /* CONFIG_CIFS_POSIX */
 288         } else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
 289                           strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
 290 #ifdef CONFIG_CIFS_POSIX
 291                 if (sb->s_flags & MS_POSIXACL)
 292                         rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
 293                                 ea_value, buf_size, ACL_TYPE_DEFAULT,
 294                                 cifs_sb->local_nls,
 295                                 cifs_sb->mnt_cifs_flags &
 296                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 297 #else
 298                 cFYI(1, ("query POSIX default ACL not supported yet"));
 299 #endif
 300         } else if (strncmp(ea_name,
 301                   CIFS_XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
 302                 cFYI(1, ("Trusted xattr namespace not supported yet"));
 303         } else if (strncmp(ea_name,
 304                   CIFS_XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
 305                 cFYI(1, ("Security xattr namespace not supported yet"));
 306         } else
 307                 cFYI(1,
 308                     ("illegal xattr request %s (only user namespace supported)",
 309                         ea_name));
 310
 311         /* We could add an additional check for streams ie
 312             if proc/fs/cifs/streamstoxattr is set then
 313                 search server for EAs or streams to
 314                 returns as xattrs */
 315
 316         if (rc == -EINVAL)
 317                 rc = -EOPNOTSUPP;
 318
 319 get_ea_exit:
 320         kfree(full_path);
 321         FreeXid(xid);
 322 #endif
 323         return rc;
 324 }
 325
 326 ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
 327 {
 328         ssize_t rc = -EOPNOTSUPP;
 329 #ifdef CONFIG_CIFS_XATTR
 330         int xid;
 331         struct cifs_sb_info *cifs_sb;
 332         struct cifsTconInfo *pTcon;
 333         struct super_block *sb;
 334         char *full_path;
 335
 336         if (direntry == NULL)
 337                 return -EIO;
 338         if (direntry->d_inode == NULL)
 339                 return -EIO;
 340         sb = direntry->d_inode->i_sb;
 341         if (sb == NULL)
 342                 return -EIO;
 343
 344         cifs_sb = CIFS_SB(sb);
 345         pTcon = cifs_sb->tcon;
 346
 347         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 348                 return -EOPNOTSUPP;
 349
 350         xid = GetXid();
 351
 352         full_path = build_path_from_dentry(direntry);
 353         if (full_path == NULL) {
 354                 FreeXid(xid);
 355                 return -ENOMEM;
 356         }
 357         /* return dos attributes as pseudo xattr */
 358         /* return alt name if available as pseudo attr */
 359
 360         /* if proc/fs/cifs/streamstoxattr is set then
 361                 search server for EAs or streams to
 362                 returns as xattrs */
 363         rc = CIFSSMBQAllEAs(xid, pTcon, full_path, data, buf_size,
 364                                 cifs_sb->local_nls,
 365                                 cifs_sb->mnt_cifs_flags &
 366                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 367
 368         kfree(full_path);
 369         FreeXid(xid);
 370 #endif
 371         return rc;
 372 }