MD4

warning

MD4 is long broken and should not be used. It is included for backwards compatibility with legacy systems

MD4 is a 128-bit cryptographic hash (RFC 1320). It is cryptographically broken and should not be used for security-sensitive applications; prefer SHA-256, SHA-3, or BLAKE2. This module is provided for compatibility with legacy systems only.

##What is MD4?

MD4 is a cryptographic hash function designed by Ron Rivest in 1990. It produces a 128-bit (16-byte) hash value from input data of arbitrary length.

Design Goals:

• Very fast in software
• Simple to implement
• Suitable for 32-bit processors

How MD4 Works:

• Processes input in 512-bit message blocks
• Uses 3 rounds of nonlinear functions
• Operates on 32-bit words with addition, rotation, and XOR operations

MD4 was one of the earliest widely-adopted hash functions and influenced later designs such as MD5 and the SHA-1 family.

MD4 is now considered cryptographically obsolete and should not be used as it has trivial collision attacks. It is included in the NoxTLS to maintain compatibility with protocls which may still use it.

You should instead use SHA-256 / SHA-384 or better

API

noxtls_md4_set_debug

void noxtls_md4_set_debug(uint8_t lvl);

Sets Module Debug level

Parameters:

• lvl — is the debug level

noxtls_md4_init

noxtls_return_t noxtls_md4_init(noxtls_sha_ctx_t * ctx);

Initialize the MD4 Context

Parameters:

• ctx — noxtls_sha_ctx_t to initialize for MD4

Returns: noxtls_return_t: NOXTLS_RETURN_SUCCESS on success.

noxtls_md4_round

noxtls_return_t noxtls_md4_round(noxtls_sha_ctx_t * ctx, const uint8_t * input);

Performs an MD4 round

Parameters:

• ctx — noxtls_sha_ctx_t (from noxtls_md4_init)
• input — 512-bit (64-byte) block to process

Returns: noxtls_return_t: NOXTLS_RETURN_SUCCESS on success, or another error code otherwise

noxtls_md4_finish

noxtls_return_t noxtls_md4_finish(noxtls_sha_ctx_t * ctx, uint8_t * hash);

Finish MD4 operation

Parameters:

• ctx — noxtls_sha_ctx_t (from noxtls_md4_init)
• hash — Output buffer for the 16-byte MD4 digest

Returns: noxtls_return_t: NOXTLS_RETURN_SUCCESS on success, or another error code otherwise

noxtls_md4_verify

noxtls_return_t noxtls_md4_verify(const uint8_t * data, uint32_t len, const uint8_t * expected);

Takes data and verifies it matches a MD4 Digest

Parameters:

• data — is the input data
• len — is the length of the input data
• expected — is the expected MD4 digest

Returns: noxtls_return_t: NOXTLS_RETURN_SUCCESS on success, or another error code otherwise