| /* |
| * fs/cifs/xattr.c |
| * |
| * Copyright (c) International Business Machines Corp., 2003, 2007 |
| * Author(s): Steve French (sfrench@us.ibm.com) |
| * |
| * This library is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Lesser General Public License as published |
| * by the Free Software Foundation; either version 2.1 of the License, or |
| * (at your option) any later version. |
| * |
| * This library 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 Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public License |
| * along with this library; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/fs.h> |
| #include <linux/posix_acl_xattr.h> |
| #include <linux/slab.h> |
| #include <linux/xattr.h> |
| #include "cifsfs.h" |
| #include "cifspdu.h" |
| #include "cifsglob.h" |
| #include "cifsproto.h" |
| #include "cifs_debug.h" |
| #include "cifs_fs_sb.h" |
| #include "cifs_unicode.h" |
| |
| #define MAX_EA_VALUE_SIZE CIFSMaxBufSize |
| #define CIFS_XATTR_CIFS_ACL "system.cifs_acl" |
| #define CIFS_XATTR_ATTRIB "cifs.dosattrib" /* full name: user.cifs.dosattrib */ |
| #define CIFS_XATTR_CREATETIME "cifs.creationtime" /* user.cifs.creationtime */ |
| /* |
| * Although these three are just aliases for the above, need to move away from |
| * confusing users and using the 20+ year old term 'cifs' when it is no longer |
| * secure, replaced by SMB2 (then even more highly secure SMB3) many years ago |
| */ |
| #define SMB3_XATTR_CIFS_ACL "system.smb3_acl" |
| #define SMB3_XATTR_ATTRIB "smb3.dosattrib" /* full name: user.smb3.dosattrib */ |
| #define SMB3_XATTR_CREATETIME "smb3.creationtime" /* user.smb3.creationtime */ |
| /* BB need to add server (Samba e.g) support for security and trusted prefix */ |
| |
| enum { XATTR_USER, XATTR_CIFS_ACL, XATTR_ACL_ACCESS, XATTR_ACL_DEFAULT }; |
| |
| static int cifs_xattr_set(const struct xattr_handler *handler, |
| struct dentry *dentry, struct inode *inode, |
| const char *name, const void *value, |
| size_t size, int flags) |
| { |
| int rc = -EOPNOTSUPP; |
| unsigned int xid; |
| struct super_block *sb = dentry->d_sb; |
| struct cifs_sb_info *cifs_sb = CIFS_SB(sb); |
| struct tcon_link *tlink; |
| struct cifs_tcon *pTcon; |
| char *full_path; |
| |
| tlink = cifs_sb_tlink(cifs_sb); |
| if (IS_ERR(tlink)) |
| return PTR_ERR(tlink); |
| pTcon = tlink_tcon(tlink); |
| |
| xid = get_xid(); |
| |
| full_path = build_path_from_dentry(dentry); |
| if (full_path == NULL) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| /* return dos attributes as pseudo xattr */ |
| /* return alt name if available as pseudo attr */ |
| |
| /* if proc/fs/cifs/streamstoxattr is set then |
| search server for EAs or streams to |
| returns as xattrs */ |
| if (size > MAX_EA_VALUE_SIZE) { |
| cifs_dbg(FYI, "size of EA value too large\n"); |
| rc = -EOPNOTSUPP; |
| goto out; |
| } |
| |
| switch (handler->flags) { |
| case XATTR_USER: |
| if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR) |
| goto out; |
| |
| if (pTcon->ses->server->ops->set_EA) |
| rc = pTcon->ses->server->ops->set_EA(xid, pTcon, |
| full_path, name, value, (__u16)size, |
| cifs_sb->local_nls, cifs_sb); |
| break; |
| |
| case XATTR_CIFS_ACL: { |
| struct cifs_ntsd *pacl; |
| |
| if (!value) |
| goto out; |
| pacl = kmalloc(size, GFP_KERNEL); |
| if (!pacl) { |
| rc = -ENOMEM; |
| } else { |
| memcpy(pacl, value, size); |
| if (value && |
| pTcon->ses->server->ops->set_acl) |
| rc = pTcon->ses->server->ops->set_acl(pacl, |
| size, inode, |
| full_path, CIFS_ACL_DACL); |
| else |
| rc = -EOPNOTSUPP; |
| if (rc == 0) /* force revalidate of the inode */ |
| CIFS_I(inode)->time = 0; |
| kfree(pacl); |
| } |
| break; |
| } |
| |
| case XATTR_ACL_ACCESS: |
| #ifdef CONFIG_CIFS_POSIX |
| if (!value) |
| goto out; |
| if (sb->s_flags & SB_POSIXACL) |
| rc = CIFSSMBSetPosixACL(xid, pTcon, full_path, |
| value, (const int)size, |
| ACL_TYPE_ACCESS, cifs_sb->local_nls, |
| cifs_remap(cifs_sb)); |
| #endif /* CONFIG_CIFS_POSIX */ |
| break; |
| |
| case XATTR_ACL_DEFAULT: |
| #ifdef CONFIG_CIFS_POSIX |
| if (!value) |
| goto out; |
| if (sb->s_flags & SB_POSIXACL) |
| rc = CIFSSMBSetPosixACL(xid, pTcon, full_path, |
| value, (const int)size, |
| ACL_TYPE_DEFAULT, cifs_sb->local_nls, |
| cifs_remap(cifs_sb)); |
| #endif /* CONFIG_CIFS_POSIX */ |
| break; |
| } |
| |
| out: |
| kfree(full_path); |
| free_xid(xid); |
| cifs_put_tlink(tlink); |
| return rc; |
| } |
| |
| static int cifs_attrib_get(struct dentry *dentry, |
| struct inode *inode, void *value, |
| size_t size) |
| { |
| ssize_t rc; |
| __u32 *pattribute; |
| |
| rc = cifs_revalidate_dentry_attr(dentry); |
| |
| if (rc) |
| return rc; |
| |
| if ((value == NULL) || (size == 0)) |
| return sizeof(__u32); |
| else if (size < sizeof(__u32)) |
| return -ERANGE; |
| |
| /* return dos attributes as pseudo xattr */ |
| pattribute = (__u32 *)value; |
| *pattribute = CIFS_I(inode)->cifsAttrs; |
| |
| return sizeof(__u32); |
| } |
| |
| static int cifs_creation_time_get(struct dentry *dentry, struct inode *inode, |
| void *value, size_t size) |
| { |
| ssize_t rc; |
| __u64 * pcreatetime; |
| |
| rc = cifs_revalidate_dentry_attr(dentry); |
| if (rc) |
| return rc; |
| |
| if ((value == NULL) || (size == 0)) |
| return sizeof(__u64); |
| else if (size < sizeof(__u64)) |
| return -ERANGE; |
| |
| /* return dos attributes as pseudo xattr */ |
| pcreatetime = (__u64 *)value; |
| *pcreatetime = CIFS_I(inode)->createtime; |
| return sizeof(__u64); |
| } |
| |
| |
| static int cifs_xattr_get(const struct xattr_handler *handler, |
| struct dentry *dentry, struct inode *inode, |
| const char *name, void *value, size_t size) |
| { |
| ssize_t rc = -EOPNOTSUPP; |
| unsigned int xid; |
| struct super_block *sb = dentry->d_sb; |
| struct cifs_sb_info *cifs_sb = CIFS_SB(sb); |
| struct tcon_link *tlink; |
| struct cifs_tcon *pTcon; |
| char *full_path; |
| |
| tlink = cifs_sb_tlink(cifs_sb); |
| if (IS_ERR(tlink)) |
| return PTR_ERR(tlink); |
| pTcon = tlink_tcon(tlink); |
| |
| xid = get_xid(); |
| |
| full_path = build_path_from_dentry(dentry); |
| if (full_path == NULL) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| /* return alt name if available as pseudo attr */ |
| switch (handler->flags) { |
| case XATTR_USER: |
| cifs_dbg(FYI, "%s:querying user xattr %s\n", __func__, name); |
| if ((strcmp(name, CIFS_XATTR_ATTRIB) == 0) || |
| (strcmp(name, SMB3_XATTR_ATTRIB) == 0)) { |
| rc = cifs_attrib_get(dentry, inode, value, size); |
| break; |
| } else if ((strcmp(name, CIFS_XATTR_CREATETIME) == 0) || |
| (strcmp(name, SMB3_XATTR_CREATETIME) == 0)) { |
| rc = cifs_creation_time_get(dentry, inode, value, size); |
| break; |
| } |
| |
| if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR) |
| goto out; |
| |
| if (pTcon->ses->server->ops->query_all_EAs) |
| rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon, |
| full_path, name, value, size, cifs_sb); |
| break; |
| |
| case XATTR_CIFS_ACL: { |
| u32 acllen; |
| struct cifs_ntsd *pacl; |
| |
| if (pTcon->ses->server->ops->get_acl == NULL) |
| goto out; /* rc already EOPNOTSUPP */ |
| |
| pacl = pTcon->ses->server->ops->get_acl(cifs_sb, |
| inode, full_path, &acllen); |
| if (IS_ERR(pacl)) { |
| rc = PTR_ERR(pacl); |
| cifs_dbg(VFS, "%s: error %zd getting sec desc\n", |
| __func__, rc); |
| } else { |
| if (value) { |
| if (acllen > size) |
| acllen = -ERANGE; |
| else |
| memcpy(value, pacl, acllen); |
| } |
| rc = acllen; |
| kfree(pacl); |
| } |
| break; |
| } |
| |
| case XATTR_ACL_ACCESS: |
| #ifdef CONFIG_CIFS_POSIX |
| if (sb->s_flags & SB_POSIXACL) |
| rc = CIFSSMBGetPosixACL(xid, pTcon, full_path, |
| value, size, ACL_TYPE_ACCESS, |
| cifs_sb->local_nls, |
| cifs_remap(cifs_sb)); |
| #endif /* CONFIG_CIFS_POSIX */ |
| break; |
| |
| case XATTR_ACL_DEFAULT: |
| #ifdef CONFIG_CIFS_POSIX |
| if (sb->s_flags & SB_POSIXACL) |
| rc = CIFSSMBGetPosixACL(xid, pTcon, full_path, |
| value, size, ACL_TYPE_DEFAULT, |
| cifs_sb->local_nls, |
| cifs_remap(cifs_sb)); |
| #endif /* CONFIG_CIFS_POSIX */ |
| break; |
| } |
| |
| /* We could add an additional check for streams ie |
| if proc/fs/cifs/streamstoxattr is set then |
| search server for EAs or streams to |
| returns as xattrs */ |
| |
| if (rc == -EINVAL) |
| rc = -EOPNOTSUPP; |
| |
| out: |
| kfree(full_path); |
| free_xid(xid); |
| cifs_put_tlink(tlink); |
| return rc; |
| } |
| |
| ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size) |
| { |
| ssize_t rc = -EOPNOTSUPP; |
| unsigned int xid; |
| struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb); |
| struct tcon_link *tlink; |
| struct cifs_tcon *pTcon; |
| char *full_path; |
| |
| if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR) |
| return -EOPNOTSUPP; |
| |
| tlink = cifs_sb_tlink(cifs_sb); |
| if (IS_ERR(tlink)) |
| return PTR_ERR(tlink); |
| pTcon = tlink_tcon(tlink); |
| |
| xid = get_xid(); |
| |
| full_path = build_path_from_dentry(direntry); |
| if (full_path == NULL) { |
| rc = -ENOMEM; |
| goto list_ea_exit; |
| } |
| /* return dos attributes as pseudo xattr */ |
| /* return alt name if available as pseudo attr */ |
| |
| /* if proc/fs/cifs/streamstoxattr is set then |
| search server for EAs or streams to |
| returns as xattrs */ |
| |
| if (pTcon->ses->server->ops->query_all_EAs) |
| rc = pTcon->ses->server->ops->query_all_EAs(xid, pTcon, |
| full_path, NULL, data, buf_size, cifs_sb); |
| list_ea_exit: |
| kfree(full_path); |
| free_xid(xid); |
| cifs_put_tlink(tlink); |
| return rc; |
| } |
| |
| static const struct xattr_handler cifs_user_xattr_handler = { |
| .prefix = XATTR_USER_PREFIX, |
| .flags = XATTR_USER, |
| .get = cifs_xattr_get, |
| .set = cifs_xattr_set, |
| }; |
| |
| /* os2.* attributes are treated like user.* attributes */ |
| static const struct xattr_handler cifs_os2_xattr_handler = { |
| .prefix = XATTR_OS2_PREFIX, |
| .flags = XATTR_USER, |
| .get = cifs_xattr_get, |
| .set = cifs_xattr_set, |
| }; |
| |
| static const struct xattr_handler cifs_cifs_acl_xattr_handler = { |
| .name = CIFS_XATTR_CIFS_ACL, |
| .flags = XATTR_CIFS_ACL, |
| .get = cifs_xattr_get, |
| .set = cifs_xattr_set, |
| }; |
| |
| /* |
| * Although this is just an alias for the above, need to move away from |
| * confusing users and using the 20 year old term 'cifs' when it is no |
| * longer secure and was replaced by SMB2/SMB3 a long time ago, and |
| * SMB3 and later are highly secure. |
| */ |
| static const struct xattr_handler smb3_acl_xattr_handler = { |
| .name = SMB3_XATTR_CIFS_ACL, |
| .flags = XATTR_CIFS_ACL, |
| .get = cifs_xattr_get, |
| .set = cifs_xattr_set, |
| }; |
| |
| static const struct xattr_handler cifs_posix_acl_access_xattr_handler = { |
| .name = XATTR_NAME_POSIX_ACL_ACCESS, |
| .flags = XATTR_ACL_ACCESS, |
| .get = cifs_xattr_get, |
| .set = cifs_xattr_set, |
| }; |
| |
| static const struct xattr_handler cifs_posix_acl_default_xattr_handler = { |
| .name = XATTR_NAME_POSIX_ACL_DEFAULT, |
| .flags = XATTR_ACL_DEFAULT, |
| .get = cifs_xattr_get, |
| .set = cifs_xattr_set, |
| }; |
| |
| const struct xattr_handler *cifs_xattr_handlers[] = { |
| &cifs_user_xattr_handler, |
| &cifs_os2_xattr_handler, |
| &cifs_cifs_acl_xattr_handler, |
| &smb3_acl_xattr_handler, /* alias for above since avoiding "cifs" */ |
| &cifs_posix_acl_access_xattr_handler, |
| &cifs_posix_acl_default_xattr_handler, |
| NULL |
| }; |