BLE Unlock API - SRP error: 0x82 Bad proof of key

XBee & XBee Gateway XBee - DigiMesh
1

Hi to all of you again. I am having a problem unlocking my BLE. I will describe step by step what I am performing:

  1. Bluetooth password:
password = "armiks"
username = "apiservice"
  1. Salt from XCTU:
s = "6fc39e80"
  1. Verifier from XCTU:
8055786FAC74B1A5AEC4631C7972FBBB688982B2708A90B519C93C20E0C2F02A066430E8B9E3459C80FE9F05DF0D579F21DB633F7936B79EC452968BA0BAFAA48B78606347992EE30F2A9EC2447D0729D46C24C96C30F849CC678E6D32DF32CAA708445E3269CA5BF7D4B65565BF3ACFA3FAF230BDB3BD46BB332839C99BC9D5
  1. SRP (Secure Remote Password) data:
    N value (from the 1024-bit group):
EEAF0AB9 ADB38DD6 9C33F80A FA8FC5E8 60726187 75FF3C0B 9EA2314C 9C256576 D674DF74 96EA81D3 383B4813 D692C6E0 E0D5D8E2 50B98BE4 8E495C1D 6089DAD1 5DC7D7B4 6154D6B6 CE8EF4AD 69B15D49 82559B29 7BCF1885 C529F566 660E57EC 68EDBC3C 05726CC0 2FD4CBF4 976EAA9A FD5138FE 8376435B 9FC61D2F C0EB06E3

Value of g:

2

Encryption type:

sha256
  1. My value of a:
a = "60975527 035CF2AD 1989806F 0407210B C81EDC04 E2762A56 AFD529DD DA2D4393"
  1. The generated value of A:
61d5e490f6f1b79547b0704c436f523dd0e560f0c64115bb72557ec44352e8903211c04692272d8b2d1a5358a2cf1b6e0bfcf99f921530ec8e39356179eae45e42ba92aeaced825171e1e8b9af6d9c03e1327f44be087ef06530e69f66615261eef54073ca11cf5858f0edfdfe15efeab349ef5d76988a3672fac47b0769447b
  1. Message to Digi Xbee (step 1):
7e00822c0161d5e490f6f1b79547b0704c436f523dd0e560f0c64115bb72557ec44352e8903211c04692272d8b2d1a5358a2cf1b6e0bfcf99f921530ec8e39356179eae45e42ba92aeaced825171e1e8b9af6d9c03e1327f44be087ef06530e69f66615261eef54073ca11cf5858f0edfdfe15efeab349ef5d76988a3672fac47b0769447b6b
  1. Answer (step 2):
7e0086ac026fc39e8023d1ee0477476df83e6b08c9d093cd5c0d86e44e90fd7754006f185edce0ed0218844ac83d77b5a97c203542abccc5e1d235c376cad53bb8b50798c4263232174f4fbc6f4597279a80c30663e88792564cbc824ddcdfc5dfe6347e0fd3b754ea43489bd17d64f1c76f6c7065bcb1cb8990ca267e59f7bcb46522706412aa611273
  1. Response analysis (salt: s=6fc39e80 - OK), value B:
23d1ee0477476df83e6b08c9d093cd5c0d86e44e90fd7754006f185edce0ed0218844ac83d77b5a97c203542abccc5e1d235c376cad53bb8b50798c4263232174f4fbc6f4597279a80c30663e88792564cbc824ddcdfc5dfe6347e0fd3b754ea43489bd17d64f1c76f6c7065bcb1cb8990ca267e59f7bcb46522706412aa6112
  1. Generate x sha256(s + sha256(username + “:” + password)) value:
ec1d9c0f48a03b6dce39ca465615a3f14bba74ab113f2446a634ac48ba37b4b4
  1. Generate the value of S (A, B, a, x):
24f1ae725e480a189380da811729e86128151ade0c0074c11caaa6b450d76b0070d6f70d44975420a23763538598e1d41a394e02ffc4c0b6f106de6c630e993ee5e9f6dd1412b9347c51a958d7364974967e1d24f91b55bdcac5022f615cffe2d94f3f4b31b4b4e4de03225810675a23cc7bf5a4f9fff339891299eab78dae38
  1. Generate the value of M1 (A, B, a, x):
7c0bbb465b264e830fd63e980a4c16f22893e3ebc8812301649f23eacb4af571
  1. Message to Digi Xbee (step 3):
7e00222c037c0bbb465b264e830fd63e980a4c16f22893e3ebc8812301649f23eacb4af5715c
  1. Error response from Digi Xbee (step 4 error)
7e0002ac82d1

I don’t know where to look for the error. I have run the generated SRP values on two scripts and the error comes out the same.
I would very much appreciate your help.

2

Have you tried to simply set the value via XCTU to see if you have the same issue?

3

Hi, thanks for your reply. I found a solution developed by kapetan in javascript that correctly establishes a connection with BLE.