fs/cifs/xattr.c

   1 /*
   2  *   fs/cifs/xattr.c
   3  *
   4  *   Copyright (c) International Business Machines  Corp., 2003
   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         down(&sb->s_vfs_rename_sem);
  66         full_path = build_path_from_dentry(direntry);
  67         up(&sb->s_vfs_rename_sem);
  68         if(full_path == NULL) {
  69                 FreeXid(xid);
  70                 return -ENOMEM;
  71         }
  72         if(ea_name == NULL) {
  73                 cFYI(1,("Null xattr names not supported"));
  74         } else if(strncmp(ea_name,CIFS_XATTR_USER_PREFIX,5)
  75                 && (strncmp(ea_name,CIFS_XATTR_OS2_PREFIX,4))) {
  76                 cFYI(1,("illegal xattr namespace %s (only user namespace supported)",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         if (full_path)
  91                 kfree(full_path);
  92         FreeXid(xid);
  93 #endif
  94         return rc;
  95 }
  96
  97 int cifs_setxattr(struct dentry * direntry, const char * ea_name,
  98         const void * ea_value, size_t value_size, int flags)
  99 {
 100         int rc = -EOPNOTSUPP;
 101 #ifdef CONFIG_CIFS_XATTR
 102         int xid;
 103         struct cifs_sb_info *cifs_sb;
 104         struct cifsTconInfo *pTcon;
 105         struct super_block * sb;
 106         char * full_path;
 107
 108         if(direntry == NULL)
 109                 return -EIO;
 110         if(direntry->d_inode == NULL)
 111                 return -EIO;
 112         sb = direntry->d_inode->i_sb;
 113         if(sb == NULL)
 114                 return -EIO;
 115         xid = GetXid();
 116
 117         cifs_sb = CIFS_SB(sb);
 118         pTcon = cifs_sb->tcon;
 119
 120         down(&sb->s_vfs_rename_sem);
 121         full_path = build_path_from_dentry(direntry);
 122         up(&sb->s_vfs_rename_sem);
 123         if(full_path == NULL) {
 124                 FreeXid(xid);
 125                 return -ENOMEM;
 126         }
 127         /* return dos attributes as pseudo xattr */
 128         /* return alt name if available as pseudo attr */
 129
 130         /* if proc/fs/cifs/streamstoxattr is set then
 131                 search server for EAs or streams to
 132                 returns as xattrs */
 133         if(value_size > MAX_EA_VALUE_SIZE) {
 134                 cFYI(1,("size of EA value too large"));
 135                 if(full_path)
 136                         kfree(full_path);
 137                 FreeXid(xid);
 138                 return -EOPNOTSUPP;
 139         }
 140
 141         if(ea_name == NULL) {
 142                 cFYI(1,("Null xattr names not supported"));
 143         } else if(strncmp(ea_name,CIFS_XATTR_USER_PREFIX,5) == 0) {
 144                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 145                         goto set_ea_exit;
 146                 if(strncmp(ea_name,CIFS_XATTR_DOS_ATTRIB,14) == 0) {
 147                         cFYI(1,("attempt to set cifs inode metadata"));
 148                 }
 149                 ea_name += 5; /* skip past user. prefix */
 150                 rc = CIFSSMBSetEA(xid,pTcon,full_path,ea_name,ea_value,
 151                         (__u16)value_size, cifs_sb->local_nls,
 152                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 153         } else if(strncmp(ea_name, CIFS_XATTR_OS2_PREFIX,4) == 0) {
 154                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 155                         goto set_ea_exit;
 156
 157                 ea_name += 4; /* skip past os2. prefix */
 158                 rc = CIFSSMBSetEA(xid,pTcon,full_path,ea_name,ea_value,
 159                         (__u16)value_size, cifs_sb->local_nls,
 160                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 161         } else {
 162                 int temp;
 163                 temp = strncmp(ea_name,POSIX_ACL_XATTR_ACCESS,
 164                         strlen(POSIX_ACL_XATTR_ACCESS));
 165                 if (temp == 0) {
 166 #ifdef CONFIG_CIFS_POSIX
 167                         if(sb->s_flags & MS_POSIXACL)
 168                                 rc = CIFSSMBSetPosixACL(xid, pTcon,full_path,
 169                                         ea_value, (const int)value_size,
 170                                         ACL_TYPE_ACCESS,cifs_sb->local_nls,
 171                                         cifs_sb->mnt_cifs_flags &
 172                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 173                         cFYI(1,("set POSIX ACL rc %d",rc));
 174 #else
 175                         cFYI(1,("set POSIX ACL not supported"));
 176 #endif
 177                 } else if(strncmp(ea_name,POSIX_ACL_XATTR_DEFAULT,strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
 178 #ifdef CONFIG_CIFS_POSIX
 179                         if(sb->s_flags & MS_POSIXACL)
 180                                 rc = CIFSSMBSetPosixACL(xid, pTcon,full_path,
 181                                         ea_value, (const int)value_size,
 182                                         ACL_TYPE_DEFAULT, cifs_sb->local_nls,
 183                                         cifs_sb->mnt_cifs_flags &
 184                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 185                         cFYI(1,("set POSIX default ACL rc %d",rc));
 186 #else
 187                         cFYI(1,("set default POSIX ACL not supported"));
 188 #endif
 189                 } else {
 190                         cFYI(1,("illegal xattr request %s (only user namespace supported)",ea_name));
 191                   /* BB what if no namespace prefix? */
 192                   /* Should we just pass them to server, except for
 193                   system and perhaps security prefixes? */
 194                 }
 195         }
 196
 197 set_ea_exit:
 198         if (full_path)
 199                 kfree(full_path);
 200         FreeXid(xid);
 201 #endif
 202         return rc;
 203 }
 204
 205 ssize_t cifs_getxattr(struct dentry * direntry, const char * ea_name,
 206          void * ea_value, size_t buf_size)
 207 {
 208         ssize_t rc = -EOPNOTSUPP;
 209 #ifdef CONFIG_CIFS_XATTR
 210         int xid;
 211         struct cifs_sb_info *cifs_sb;
 212         struct cifsTconInfo *pTcon;
 213         struct super_block * sb;
 214         char * full_path;
 215
 216         if(direntry == NULL)
 217                 return -EIO;
 218         if(direntry->d_inode == NULL)
 219                 return -EIO;
 220         sb = direntry->d_inode->i_sb;
 221         if(sb == NULL)
 222                 return -EIO;
 223
 224         xid = GetXid();
 225
 226         cifs_sb = CIFS_SB(sb);
 227         pTcon = cifs_sb->tcon;
 228
 229         down(&sb->s_vfs_rename_sem);
 230         full_path = build_path_from_dentry(direntry);
 231         up(&sb->s_vfs_rename_sem);
 232         if(full_path == NULL) {
 233                 FreeXid(xid);
 234                 return -ENOMEM;
 235         }
 236         /* return dos attributes as pseudo xattr */
 237         /* return alt name if available as pseudo attr */
 238         if(ea_name == NULL) {
 239                 cFYI(1,("Null xattr names not supported"));
 240         } else if(strncmp(ea_name,CIFS_XATTR_USER_PREFIX,5) == 0) {
 241                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 242                         goto get_ea_exit;
 243
 244                 if(strncmp(ea_name,CIFS_XATTR_DOS_ATTRIB,14) == 0) {
 245                         cFYI(1,("attempt to query cifs inode metadata"));
 246                         /* revalidate/getattr then populate from inode */
 247                 } /* BB add else when above is implemented */
 248                 ea_name += 5; /* skip past user. prefix */
 249                 rc = CIFSSMBQueryEA(xid,pTcon,full_path,ea_name,ea_value,
 250                         buf_size, cifs_sb->local_nls,
 251                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 252         } else if(strncmp(ea_name, CIFS_XATTR_OS2_PREFIX,4) == 0) {
 253                 if(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
 254                         goto get_ea_exit;
 255
 256                 ea_name += 4; /* skip past os2. prefix */
 257                 rc = CIFSSMBQueryEA(xid,pTcon,full_path,ea_name,ea_value,
 258                         buf_size, cifs_sb->local_nls,
 259                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 260         } else if(strncmp(ea_name,POSIX_ACL_XATTR_ACCESS,strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
 261 #ifdef CONFIG_CIFS_POSIX
 262                 if(sb->s_flags & MS_POSIXACL)
 263                         rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
 264                                 ea_value, buf_size, ACL_TYPE_ACCESS,
 265                                 cifs_sb->local_nls,
 266                                 cifs_sb->mnt_cifs_flags &
 267                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 268 #else
 269                 cFYI(1,("query POSIX ACL not supported yet"));
 270 #endif /* CONFIG_CIFS_POSIX */
 271         } else if(strncmp(ea_name,POSIX_ACL_XATTR_DEFAULT,strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
 272 #ifdef CONFIG_CIFS_POSIX
 273                 if(sb->s_flags & MS_POSIXACL)
 274                         rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
 275                                 ea_value, buf_size, ACL_TYPE_DEFAULT,
 276                                 cifs_sb->local_nls,
 277                                 cifs_sb->mnt_cifs_flags &
 278                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 279 #else
 280                 cFYI(1,("query POSIX default ACL not supported yet"));
 281 #endif
 282         } else if(strncmp(ea_name,
 283                   CIFS_XATTR_TRUSTED_PREFIX,XATTR_TRUSTED_PREFIX_LEN) == 0) {
 284                 cFYI(1,("Trusted xattr namespace not supported yet"));
 285         } else if(strncmp(ea_name,
 286                   CIFS_XATTR_SECURITY_PREFIX,XATTR_SECURITY_PREFIX_LEN) == 0) {
 287                 cFYI(1,("Security xattr namespace not supported yet"));
 288         } else {
 289                 cFYI(1,("illegal xattr name request %s (only user namespace supported)",ea_name));
 290         }
 291
 292         /* We could add an additional check for streams ie
 293             if proc/fs/cifs/streamstoxattr is set then
 294                 search server for EAs or streams to
 295                 returns as xattrs */
 296
 297         if(rc == -EINVAL)
 298                 rc = -EOPNOTSUPP;
 299
 300 get_ea_exit:
 301         if (full_path)
 302                 kfree(full_path);
 303         FreeXid(xid);
 304 #endif
 305         return rc;
 306 }
 307
 308 ssize_t cifs_listxattr(struct dentry * direntry, char * data, size_t buf_size)
 309 {
 310         ssize_t rc = -EOPNOTSUPP;
 311 #ifdef CONFIG_CIFS_XATTR
 312         int xid;
 313         struct cifs_sb_info *cifs_sb;
 314         struct cifsTconInfo *pTcon;
 315         struct super_block * sb;
 316         char * full_path;
 317
 318         if(direntry == NULL)
 319                 return -EIO;
 320         if(direntry->d_inode == NULL)
 321                 return -EIO;
 322         sb = direntry->d_inode->i_sb;
 323         if(sb == NULL)
 324                 return -EIO;
 325         xid = GetXid();
 326
 327         cifs_sb = CIFS_SB(sb);
 328         pTcon = cifs_sb->tcon;
 329
 330         down(&sb->s_vfs_rename_sem);
 331         full_path = build_path_from_dentry(direntry);
 332         up(&sb->s_vfs_rename_sem);
 333         if(full_path == NULL) {
 334                 FreeXid(xid);
 335                 return -ENOMEM;
 336         }
 337         /* return dos attributes as pseudo xattr */
 338         /* return alt name if available as pseudo attr */
 339
 340         /* if proc/fs/cifs/streamstoxattr is set then
 341                 search server for EAs or streams to
 342                 returns as xattrs */
 343         rc = CIFSSMBQAllEAs(xid,pTcon,full_path,data,buf_size,
 344                                 cifs_sb->local_nls,
 345                                 cifs_sb->mnt_cifs_flags &
 346                                         CIFS_MOUNT_MAP_SPECIAL_CHR);
 347
 348         if (full_path)
 349                 kfree(full_path);
 350         FreeXid(xid);
 351 #endif
 352         return rc;
 353 }