mfsymlinks support for SMB2.1/SMB3. Part 2 query symlink

Adds support on SMB2.1 and SMB3 mounts for emulation of symlinks
via the "Minshall/French" symlink format already used for cifs
mounts when mfsymlinks mount option is used (and also used by Apple).
  http://wiki.samba.org/index.php/UNIX_Extensions#Minshall.2BFrench_symlinks
This second patch adds support to query them (recognize them as symlinks
and read them).  Third version of patch makes minor corrections
to error handling.

Signed-off-by: Steve French <smfrench@gmail.com>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
This commit is contained in:
Steve French 2014-09-16 07:18:19 -05:00
parent 5ab97578cb
commit c22870ea2d
3 changed files with 75 additions and 1 deletions

View File

@ -28,7 +28,9 @@
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#ifdef CONFIG_CIFS_SMB2
#include "smb2proto.h"
#endif
/*
* M-F Symlink Functions - Begin
@ -401,6 +403,72 @@ cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
return rc;
}
/*
* SMB 2.1/SMB3 Protocol specific functions
*/
#ifdef CONFIG_CIFS_SMB2
int
smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char *pbuf, unsigned int *pbytes_read)
{
int rc;
struct cifs_fid fid;
struct cifs_open_parms oparms;
struct cifs_io_parms io_parms;
int buf_type = CIFS_NO_BUFFER;
__le16 *utf16_path;
__u8 oplock = SMB2_OPLOCK_LEVEL_II;
struct smb2_file_all_info *pfile_info = NULL;
oparms.tcon = tcon;
oparms.cifs_sb = cifs_sb;
oparms.desired_access = GENERIC_READ;
oparms.create_options = CREATE_NOT_DIR;
if (backup_cred(cifs_sb))
oparms.create_options |= CREATE_OPEN_BACKUP_INTENT;
oparms.disposition = FILE_OPEN;
oparms.fid = &fid;
oparms.reconnect = false;
utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
if (utf16_path == NULL)
return -ENOMEM;
pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
GFP_KERNEL);
if (pfile_info == NULL) {
kfree(utf16_path);
return -ENOMEM;
}
rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL);
if (rc)
goto qmf_out_open_fail;
if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
/* it's not a symlink */
rc = -ENOENT; /* Is there a better rc to return? */
goto qmf_out;
}
io_parms.netfid = fid.netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
io_parms.persistent_fid = fid.persistent_fid;
io_parms.volatile_fid = fid.volatile_fid;
rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
qmf_out:
SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
qmf_out_open_fail:
kfree(utf16_path);
kfree(pfile_info);
return rc;
}
int
smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
@ -461,7 +529,7 @@ smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
kfree(utf16_path);
return rc;
}
#endif /* CONFIG_CIFS_SMB2 */
/*
* M-F Symlink Functions - End

View File

@ -1452,6 +1452,7 @@ struct smb_version_operations smb21_operations = {
.rename = smb2_rename_path,
.create_hardlink = smb2_create_hardlink,
.query_symlink = smb2_query_symlink,
.query_mf_symlink = smb3_query_mf_symlink,
.create_mf_symlink = smb3_create_mf_symlink,
.open = smb2_open_file,
.set_fid = smb2_set_fid,
@ -1532,6 +1533,7 @@ struct smb_version_operations smb30_operations = {
.rename = smb2_rename_path,
.create_hardlink = smb2_create_hardlink,
.query_symlink = smb2_query_symlink,
.query_mf_symlink = smb3_query_mf_symlink,
.create_mf_symlink = smb3_create_mf_symlink,
.open = smb2_open_file,
.set_fid = smb2_set_fid,

View File

@ -85,6 +85,10 @@ extern int smb2_create_hardlink(const unsigned int xid, struct cifs_tcon *tcon,
extern int smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char *pbuf, unsigned int *pbytes_written);
extern int smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb,
const unsigned char *path, char *pbuf,
unsigned int *pbytes_read);
extern int smb2_open_file(const unsigned int xid,
struct cifs_open_parms *oparms,
__u32 *oplock, FILE_ALL_INFO *buf);