gRPC-Web koristi Content-Type: application/grpc-web-text u zahtevima koji su vrste protobuf u kodiranom obliku base64, možete koristiti gprc-coder alat, a takođe možete instalirati i njegov Burp Suite Extension.
Možete koristiti gRPC-Web Coder Burp Suite ekstenziju u gRPC-Web Pentest Suite koja je jednostavnija. Uputstva za instalaciju i upotrebu možete pročitati na njegovom repozitorijumu.
Analiziranje gRPC-Web Javascript fajlova
U svakoj gRPC-Web aplikaciji postoji barem jedan Javascript fajl. Možete analizirati fajl kako biste pronašli nove poruke, endpointe i servise. Pokušajte koristiti gRPC-Scan alat.
Preuzmite Javascript gRPC-Web fajl
Skenirajte ga pomoću grpc-scan.py:
python3grpc-scan.py--filemain.js
Analizirajte izlaz i testirajte nove krajnje tačke i nove servise:
Output:
Found Endpoints:
/grpc.gateway.testing.EchoService/Echo
/grpc.gateway.testing.EchoService/EchoAbort
/grpc.gateway.testing.EchoService/NoOp
/grpc.gateway.testing.EchoService/ServerStreamingEcho
/grpc.gateway.testing.EchoService/ServerStreamingEchoAbort
Found Messages:
grpc.gateway.testing.EchoRequest:
+------------+--------------------+--------------+
| Field Name | Field Type | Field Number |
+============+====================+==============+
| Message | Proto3StringField | 1 |
+------------+--------------------+--------------+
| Name | Proto3StringField | 2 |
+------------+--------------------+--------------+
| Age | Proto3IntField | 3 |
+------------+--------------------+--------------+
| IsAdmin | Proto3BooleanField | 4 |
+------------+--------------------+--------------+
| Weight | Proto3FloatField | 5 |
+------------+--------------------+--------------+
| Test | Proto3StringField | 6 |
+------------+--------------------+--------------+
| Test2 | Proto3StringField | 7 |
+------------+--------------------+--------------+
| Test3 | Proto3StringField | 16 |
+------------+--------------------+--------------+
| Test4 | Proto3StringField | 20 |
+------------+--------------------+--------------+
grpc.gateway.testing.EchoResponse:
+--------------+--------------------+--------------+
| Field Name | Field Type | Field Number |
+==============+====================+==============+
| Message | Proto3StringField | 1 |
+--------------+--------------------+--------------+
| Name | Proto3StringField | 2 |
+--------------+--------------------+--------------+
| Age | Proto3IntField | 3 |
+--------------+--------------------+--------------+
| IsAdmin | Proto3BooleanField | 4 |
+--------------+--------------------+--------------+
| Weight | Proto3FloatField | 5 |
+--------------+--------------------+--------------+
| Test | Proto3StringField | 6 |
+--------------+--------------------+--------------+
| Test2 | Proto3StringField | 7 |
+--------------+--------------------+--------------+
| Test3 | Proto3StringField | 16 |
+--------------+--------------------+--------------+
| Test4 | Proto3StringField | 20 |
+--------------+--------------------+--------------+
| MessageCount | Proto3IntField | 8 |
+--------------+--------------------+--------------+
grpc.gateway.testing.ServerStreamingEchoRequest:
+-----------------+-------------------+--------------+
| Field Name | Field Type | Field Number |
+=================+===================+==============+
| Message | Proto3StringField | 1 |
+-----------------+-------------------+--------------+
| MessageCount | Proto3IntField | 2 |
+-----------------+-------------------+--------------+
| MessageInterval | Proto3IntField | 3 |
+-----------------+-------------------+--------------+
grpc.gateway.testing.ServerStreamingEchoResponse:
+------------+-------------------+--------------+
| Field Name | Field Type | Field Number |
+============+===================+==============+
| Message | Proto3StringField | 1 |
+------------+-------------------+--------------+
grpc.gateway.testing.ClientStreamingEchoRequest:
+------------+-------------------+--------------+
| Field Name | Field Type | Field Number |
+============+===================+==============+
| Message | Proto3StringField | 1 |
+------------+-------------------+--------------+
grpc.gateway.testing.ClientStreamingEchoResponse:
+--------------+----------------+--------------+
| Field Name | Field Type | Field Number |
+==============+================+==============+
| MessageCount | Proto3IntField | 1 |
+--------------+----------------+--------------+