diff --git a/mtprotoproxy.py b/mtprotoproxy.py
index 741591a..0ac2dac 100755
--- a/mtprotoproxy.py
+++ b/mtprotoproxy.py
@@ -1345,15 +1345,19 @@ def get_middleproxy_aes_key_and_iv(nonce_srv, nonce_clt, clt_ts, srv_ip, clt_por
     return key, iv
 
 
-async def middleproxy_handshake_after_connect(host, port, reader_tgt, writer_tgt):
-    """ The first stage of middleproxy handshake """
+async def middleproxy_handshake(host, port, reader_tgt, writer_tgt):
+    """ The most logic of middleproxy handshake, launched in pool """
     START_SEQ_NO = -2
     NONCE_LEN = 16
 
+    RPC_HANDSHAKE = b"\xf5\xee\x82\x76"
     RPC_NONCE = b"\xaa\x87\xcb\x7a"
+    # pass as consts to simplify code
+    RPC_FLAGS = b"\x00\x00\x00\x00"
     CRYPTO_AES = b"\x01\x00\x00\x00"
 
     RPC_NONCE_ANS_LEN = 32
+    RPC_HANDSHAKE_ANS_LEN = 32
 
     writer_tgt = MTProtoFrameStreamWriter(writer_tgt, START_SEQ_NO)
     key_selector = PROXY_SECRET[:4]
@@ -1379,49 +1383,12 @@ async def middleproxy_handshake_after_connect(host, port, reader_tgt, writer_tgt
     if rpc_type != RPC_NONCE or rpc_key_selector != key_selector or rpc_schema != CRYPTO_AES:
         raise ConnectionAbortedError("bad rpc answer")
 
-    return reader_tgt, writer_tgt, nonce, rpc_nonce, crypto_ts
-
-
-async def do_middleproxy_handshake(proto_tag, dc_idx, cl_ip, cl_port):
-    RPC_HANDSHAKE = b"\xf5\xee\x82\x76"
-    # pass as consts to simplify code
-    RPC_FLAGS = b"\x00\x00\x00\x00"
-
-    RPC_HANDSHAKE_ANS_LEN = 32
-
-    global my_ip_info
-    global tg_connection_pool
-
-    use_ipv6_tg = (my_ip_info["ipv6"] and (config.PREFER_IPV6 or not my_ip_info["ipv4"]))
-    use_ipv6_clt = (":" in cl_ip)
-
-    if use_ipv6_tg:
-        if dc_idx not in TG_MIDDLE_PROXIES_V6:
-            return False
-        addr, port = myrandom.choice(TG_MIDDLE_PROXIES_V6[dc_idx])
-    else:
-        if dc_idx not in TG_MIDDLE_PROXIES_V4:
-            return False
-        addr, port = myrandom.choice(TG_MIDDLE_PROXIES_V4[dc_idx])
-
-    try:
-        ret = await tg_connection_pool.get_connection(addr, port,
-                                                      middleproxy_handshake_after_connect)
-        reader_tgt, writer_tgt, nonce, rpc_nonce, crypto_ts = ret
-    except ConnectionRefusedError as E:
-        print_err("The Telegram server %d (%s %s) is refusing connections" % (dc_idx, addr, port))
-        return False
-    except ConnectionAbortedError as E:
-        print_err("The Telegram server connection is bad: %d (%s %s) %s" % (dc_idx, addr, port, E))
-        return False
-    except (OSError, asyncio.TimeoutError) as E:
-        print_err("Unable to connect to the Telegram server %d (%s %s)" % (dc_idx, addr, port))
-        return False
-
     # get keys
     tg_ip, tg_port = writer_tgt.upstream.get_extra_info('peername')[:2]
     my_ip, my_port = writer_tgt.upstream.get_extra_info('sockname')[:2]
 
+    use_ipv6_tg = (":" in tg_ip)
+
     if not use_ipv6_tg:
         if my_ip_info["ipv4"]:
             # prefer global ip settings to work behind NAT
@@ -1472,11 +1439,42 @@ async def do_middleproxy_handshake(proto_tag, dc_idx, cl_ip, cl_port):
 
     handshake_ans = await reader_tgt.read(1)
     if len(handshake_ans) != RPC_HANDSHAKE_ANS_LEN:
-        return False
+        raise ConnectionAbortedError("bad rpc handshake answer length")
 
     handshake_type, handshake_flags, handshake_sender_pid, handshake_peer_pid = (
         handshake_ans[:4], handshake_ans[4:8], handshake_ans[8:20], handshake_ans[20:32])
     if handshake_type != RPC_HANDSHAKE or handshake_peer_pid != SENDER_PID:
+        raise ConnectionAbortedError("bad rpc handshake answer")
+
+    return reader_tgt, writer_tgt, my_ip, my_port
+
+
+async def do_middleproxy_handshake(proto_tag, dc_idx, cl_ip, cl_port):
+    global my_ip_info
+    global tg_connection_pool
+
+    use_ipv6_tg = (my_ip_info["ipv6"] and (config.PREFER_IPV6 or not my_ip_info["ipv4"]))
+
+    if use_ipv6_tg:
+        if dc_idx not in TG_MIDDLE_PROXIES_V6:
+            return False
+        addr, port = myrandom.choice(TG_MIDDLE_PROXIES_V6[dc_idx])
+    else:
+        if dc_idx not in TG_MIDDLE_PROXIES_V4:
+            return False
+        addr, port = myrandom.choice(TG_MIDDLE_PROXIES_V4[dc_idx])
+
+    try:
+        ret = await tg_connection_pool.get_connection(addr, port, middleproxy_handshake)
+        reader_tgt, writer_tgt, my_ip, my_port = ret
+    except ConnectionRefusedError as E:
+        print_err("The Telegram server %d (%s %s) is refusing connections" % (dc_idx, addr, port))
+        return False
+    except ConnectionAbortedError as E:
+        print_err("The Telegram server connection is bad: %d (%s %s) %s" % (dc_idx, addr, port, E))
+        return False
+    except (OSError, asyncio.TimeoutError) as E:
+        print_err("Unable to connect to the Telegram server %d (%s %s)" % (dc_idx, addr, port))
         return False
 
     writer_tgt = ProxyReqStreamWriter(writer_tgt, cl_ip, cl_port, my_ip, my_port, proto_tag)