See also: Kernel Index, Init, System Services

This directory contains cryptographic algorithm implementations used by the kernel.

Components

MD5

md5.c — MD5 message-digest algorithm.

  • 16-byte (128-bit) digest output

  • 64-byte block size

  • MD5_Init(), MD5_Update(), MD5_Final() — Streaming API

  • MD5_Calculate() — Single-call hash

  • MD5_ToHex() — Digest to hex string

  • MD5_SelfTest() — Known-answer test

SHA1

sha1.c — SHA-1 secure hash algorithm.

  • 20-byte (160-bit) digest output

  • 64-byte block size

  • SHA1_Init(), SHA1_Update(), SHA1_Final() — Streaming API

  • SHA1_Calculate() — Single-call hash

  • SHA1_ToHex() — Digest to hex string

  • SHA1_SelfTest() — Known-answer test

Self-Test Runner

crypto.c — Crypto_SelfTest() is called during kernel initialization to verify both MD5 and SHA1 implementations.

Typical Work in This Area

  • Add additional algorithms (AES, SHA256, etc.)

  • Implement kernel entropy pool

  • Use hash functions for module integrity verification

Revision History

v1.0

Initial crypto subsystem documentation