Signature (Checksum) Documentation
Signature (Checksum) Generation Documentation#
This document outlines the technical mechanism for generating a secure signature (checksum) for API requests. This process ensures data integrity and authenticity by combining the request payload with a random salt, hashing the result, and encrypting the final string.
1. Core Logic Workflow#
The signature generation process consists of four main stages:String Payload: If the input is a direct string (e.g., a JSON request body), it is used as is.
Dictionary/Array Payload: If the input is a key-value dictionary, the parameters are first sorted alphabetically by their keys (Ordinal sort). The values are then concatenated, separated by a pipe character |, with the trailing pipe removed.
B. Random Salt Generation & Concatenation#
A random string of exactly 4 characters is generated.
The characters are randomly picked from a specific predefined charset:
@#!abcdefghijklmonpqrstuvwxyz#@01234567890123456789#@ABCDEFGHIJKLMNOPQRSTUVWXYZ#@
The original input string is concatenated with a pipe | and the random string:
Format: input + "|" + randomString
C. Hashing (SHA-256)#
The concatenated string from the previous step is converted to a byte array using UTF-8 encoding.
It is hashed using the SHA-256 algorithm.
The resulting hash is converted to a lowercase Hexadecimal string (without any dashes).
D. Final Encryption (AES-CBC)#
The generated Hex hash is concatenated with the 4-character random string:
Format: hash + randomString
Encryption Key: The provided secret key is hashed using SHA-256 (with ASCII encoding) to produce a 256-bit key for AES.
Encryption Process: The concatenated string is encrypted using the AES (Rijndael) algorithm with the following parameters:Mode: CBC (Cipher Block Chaining)
IV (Initialization Vector): A static 16-byte array: "@@@@&&&&####$$$$"
Finally, the encrypted byte array is converted into a Base64 string. This Base64 string is the final Signature.
2. Code Implementations#
Below are practical code examples in multiple languages to generate the signature.Modified at 2026-05-19 15:45:01
