static int
CIFSQueryMFSymLink(const int xid, struct cifs_tcon *tcon,
const unsigned char *searchName, char **symlinkinfo,
const struct nls_table *nls_codepage, int remap)
{
int rc;
int oplock = 0;
__u16 netfid = 0;
u8 *buf;
char *pbuf;
unsigned int bytes_read = 0;
int buf_type = CIFS_NO_BUFFER;
unsigned int link_len = 0;
struct cifs_io_parms io_parms;
FILE_ALL_INFO file_info;
rc = CIFSSMBOpen(xid, tcon, searchName, FILE_OPEN, GENERIC_READ,
CREATE_NOT_DIR, &netfid, &oplock, &file_info,
nls_codepage, remap);
if (rc != 0)
return rc;
if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
CIFSSMBClose(xid, tcon, netfid);
/* it's not a symlink */
return -EINVAL;
}
buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
pbuf = buf;
io_parms.netfid = netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
rc = CIFSSMBRead(xid, &io_parms, &bytes_read, &pbuf, &buf_type);
CIFSSMBClose(xid, tcon, netfid);
if (rc != 0) {
kfree(buf);
return rc;
}
rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, symlinkinfo);
kfree(buf);
if (rc != 0)
return rc;
return 0;
}
int
CIFSCheckMFSymlink(struct cifs_fattr *fattr,
const unsigned char *path,
struct cifs_sb_info *cifs_sb, int xid)
{
int rc;
int oplock = 0;
__u16 netfid = 0;
struct tcon_link *tlink;
struct cifsTconInfo *pTcon;
u8 *buf;
char *pbuf;
unsigned int bytes_read = 0;
int buf_type = CIFS_NO_BUFFER;
unsigned int link_len = 0;
FILE_ALL_INFO file_info;
if (!CIFSCouldBeMFSymlink(fattr))
/* it's not a symlink */
return 0;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
pTcon = tlink_tcon(tlink);
rc = CIFSSMBOpen(xid, pTcon, path, FILE_OPEN, GENERIC_READ,
CREATE_NOT_DIR, &netfid, &oplock, &file_info,
cifs_sb->local_nls,
cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR);
if (rc != 0)
goto out;
if (file_info.EndOfFile != CIFS_MF_SYMLINK_FILE_SIZE) {
CIFSSMBClose(xid, pTcon, netfid);
/* it's not a symlink */
goto out;
}
buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
if (!buf) {
rc = -ENOMEM;
goto out;
}
pbuf = buf;
rc = CIFSSMBRead(xid, pTcon, netfid,
CIFS_MF_SYMLINK_FILE_SIZE /* length */,
0 /* offset */,
&bytes_read, &pbuf, &buf_type);
CIFSSMBClose(xid, pTcon, netfid);
if (rc != 0) {
kfree(buf);
goto out;
}
rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, NULL);
kfree(buf);
if (rc == -EINVAL) {
/* it's not a symlink */
rc = 0;
goto out;
}
if (rc != 0)
goto out;
/* it is a symlink */
fattr->cf_eof = link_len;
fattr->cf_mode &= ~S_IFMT;
fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
fattr->cf_dtype = DT_LNK;
out:
cifs_put_tlink(tlink);
return rc;
}