man pages section 3: Library Interfaces and Headers

libmd(3LIB)

Name

libmd - Message Digest library

Synopsis

cc [ flag... ] file... –lmd [ library... ]
#include <md4.h>
#include <md5.h>
#include <sha1.h>
#include <sha2.h>
#include <sha3.h>

Description

Functions in this library provide hashing routines for MD4 (RFC1320), MD5 (RFC1321), SHA1 (RFC3174), SHA224 (FIPS 180-2), SHA256 (FIPS 180-2), SHA384 (FIPS 180-2), SHA512 (FIPS 180-2), and SHA512/t (FIPS 180-4) for t = 224 and 256 and the SHA3 (FIPS 202) family of hash functions (224, 256, 384 and 512-bit versions).

INTERFACES

The shared object libmd.so.1 provides the public interfaces defined below. See intro(3) for additional information on shared object interfaces.

MD4Final MD4Init MD4Update md5_calc MD5Final MD5Init MD5Update SHA1Final SHA1Init SHA1Update SHA224Final SHA224Init SHA224Update SHA256Final SHA256Init SHA256Update SHA2Final SHA2Init SHA2Update SHA384Final SHA384Init SHA384Update SHA512Final SHA512Init SHA512Update SHA3Init SHA3Update SHA3Final

The shared object libmd.so.1 also provides these public interfaces that implement variants of SHA-2 and may perform faster on some 64-bit processors:

SHA512_t_Final SHA512_t_Init SHA512_t_Update

The digest values produced by the SHA512/224 and SHA512/256 functions are not the same as those digest values produced by the corresponding SHA2 functions.

Security

The MD4 and MD5 algorithms are currently considered weak for cryptographic use. The algorithms should be used only for compatibility with legacy systems or protocols.

The SHA1 algorithm is also believed to have some weaknesses. Migration to one of the SHA2 algorithms—including SHA224, SHA256, SHA386 or SHA512— or a member of the SHA3 family is highly recommended when compatibility with data formats and on wire protocols permit doing so.

Files

/lib/libmd.so.1

shared object

/lib/64/libmd.so.1

64-bit shared object

Attributes

See attributes(7) for descriptions of the following attributes:

ATTRIBUTE TYPE ATTRIBUTE VALUE Availability system/library/security/crypto Interface Stability Committed MT-Level MT-Safe