About SHA512/256 hash
SHA-512/256 is a variant of the SHA-2 (Secure Hash Algorithm 2) family of cryptographic hash functions. It is based on the SHA-512 algorithm but produces a truncated 256-bit (32-byte) hash value, typically represented as a 64-character hexadecimal number.
How SHA-512/256 Works:
- Padding: The input message is padded so that its length is a multiple of 1024 bits, leaving space for the message length.
- Appending Length: The original message length (in bits) is appended to the end of the padded message.
- Initializing Variables: SHA-512/256 initializes eight variables to specific constants. These variables serve as the initial hash values for the algorithm.
- Processing Message in Blocks: The padded message is processed in 1024-bit blocks. Each block undergoes multiple rounds of hashing using logical and bitwise operations.
- Truncation: After processing all blocks, the full 512-bit hash value is computed. SHA-512/256 then truncates this value to a 256-bit hash value.
- Final Hash Value: The resulting 256-bit hash value is the SHA-512/256 hash of the input message.
SHA-512/256 provides a balance between the stronger security of SHA-512 and a shorter hash length suitable for certain applications. It is used in scenarios where a stronger hash function than SHA-256 is desired, but the full SHA-512 output length is not necessary.