def verify(local_skt, auth_method):
"""
Verify client
"""
try:
plt_head = local_skt.recv(2)
ver, nmethods = struct.unpack("!BB", plt_head)
except struct.error as e:
logger.error(e)
return False
all_methods = [ord(local_skt.recv(1)) for _ in range(nmethods)]
ensure_socks_version(SOCKS_VERSION, ver)
if auth_method not in all_methods:
raise ex.ProtocolException("no matched authentication method")
local_skt.sendall(struct.pack("!BB", ver, auth_method))
if auth_method == USERNAME_PASSWORD:
if verify_credentials(local_skt, USERNAME, PASSWORD):
# verify success
pass
else:
raise ex.ProtocolException("username/password verify failed")
logger.info("verify success...")
return True
def check_version(version):
""" check protocol version
:param version: protocol version
"""
if version != VERSION:
raise ex.ProtocolException('mismatched protocol version')
def handle_protocol(self):
head = self.proxy_skt.recv(8)
ver, conn_type, ip, port = struct.unpack("!BBIH", head)
raw.check_version(ver)
ip = socket.inet_ntoa(struct.pack("!I", ip))
glogger.debug("ver: %s, type: %s, addr: %s:%s", ver, conn_type, ip,
port)
if conn_type == raw.NEW_CONN:
target_skt = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
target_skt.settimeout(3)
target_skt.connect((ip, port))
except (ConnectionRefusedError, socket.timeout):
raise ex.ProtocolException("connect to target server failed")
self.target_skt = target_skt
return target_skt
raise ex.ProtocolException("proxy protocol resolution failed")
def handle_protocol(self, proxy_addr, target_addr):
"""
:param target_addr: (ip, port)
:returns: bool, connect success|failed
:rtype:
"""
ip, port = target_addr
ip = ip2int(ip)
head = struct.pack("!BBIH", 1, 1, ip, port)
try:
self.proxy_skt.connect(proxy_addr)
except ConnectionRefusedError:
raise ex.ProtocolException("proxy socket connect failed")
self.proxy_skt.sendall(head)
return True
def handle_protocol(self):
ok, target_addr = socks5.serve(self.local_skt)
if ok:
self.target_addr = target_addr
else:
raise ex.ProtocolException("socks5 resolution falied")
def ensure_socks_version(expected, actual):
if expected != actual:
raise ex.ProtocolException("SOCKS version is not 5")