The hash-algorithms Library

The hash-algorithms library provides consistent access to a variety of hash algorithms:

• md5

• sha1

• sha224

• sha256

• sha384

• sha512

Hashing an entire string at once can be done via the functions named after each hash:

let digest = sha1("Some text");

If you want a printable digest, use hexdigest(<byte-vector>):

let hexdigest = hexdigest(sha1("Some text"));

If you want to hash multiple strings into a single digest (useful when streaming), you can use the update-hash and digest functions:

let hash = make(<sha1>);
update-hash(hash, "Some");
update-hash(hash, " ");
update-hash(hash, "text");
let digest = digest(hash);
// hexdigest works on hashes as well:
let hexdigest = hexdigest(hash);

The hash-algorithms Module

<hash> Class

Superclasses

<object>

digest-size Generic function

Returns the digest size of the hash algorithm.

Signature

digest-size (hash) => (digest-size)

Parameters

• hash – An instance of <hash>.

Values

• digest-size – An instance of <integer>.

block-size Generic function

Returns the block size of the hash algorithm.

Signature

block-size (hash) => (block-size)

Parameters

• hash – An instance of <hash>.

Values

• block-size – An instance of <integer>.

update-hash Generic function

Add more data to the hash.

Signature

update-hash (hash, input) => ()

Parameters

• hash – An instance of <hash>.

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Discussion

Add more data to the hash. This is useful when streaming data or the data is available in multiple strings and you wish to avoid the overhead of concatenation.

Calling update-hash multiple times is equivalent to calling it once with a concatenation of the arguments:

let hash-separate = make(<sha1>);
update-hash(hash-separate, "Some");
update-hash(hash-separate, " ");
update-hash(hash-separate, "text");
let digest-separate = digest(hash-separate);

let hash-combined = make(<sha1>);
update-hash(hash-combined, "Some text");
let digest-combined = digest(hash-combined);

// digest-separate and digest-combined will be the same

See also

• digest

• hexdigest(<hash>)

• hexdigest(<byte-vector>)

digest Generic function

Signature

digest (hash) => (digest)

Parameters

• hash – An instance of <hash>.

Values

• digest – An instance of <byte-vector>.

Discussion

The return value digest is binary data and may include null bytes. To display this result in text form, use hexdigest(<hash>) or hexdigest(<byte-vector>).

Use update-hash to add data to the hash.

See also

• update-hash

• hexdigest(<hash>)

• hexdigest(<byte-vector>)

hexdigest(<hash>) Method

Returns the digest for the given hash as a hexadecimal string.

Signature

hexdigest (hash) => (hexdigest)

Parameters

• hash – An instance of <hash>.

Values

• hexdigest – An instance of <byte-string>.

See also

• digest

• hexdigest(<byte-vector>)

hexdigest(<byte-vector>) Method

Returns the digest given as a hexadecimal string.

Signature

hexdigest (digest) => (hexdigest)

Parameters

• digest – An instance of <byte-vector>.

Values

• hexdigest – An instance of <byte-string>.

See also

• digest

• hexdigest(<hash>)

MD5

<md5> Class

Superclasses

<hash>

md5 Function

Signature

md5 (input) => (digest)

Parameters

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Values

• digest – An instance of <byte-vector>.

SHA-1

<sha1> Class

Superclasses

<hash>

sha1 Function

Signature

sha1 (input) => (digest)

Parameters

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Values

• digest – An instance of <byte-vector>.

SHA-2

<sha256> Class

Superclasses

<hash>

sha256 Function

Signature

sha256 (input) => (digest)

Parameters

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Values

• digest – An instance of <byte-vector>.

<sha224> Class

Superclasses

<hash>

sha224 Function

Signature

sha224 (input) => (digest)

Parameters

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Values

• digest – An instance of <byte-vector>.

<sha384> Class

Superclasses

<hash>

sha384 Function

Signature

sha384 (input) => (digest)

Parameters

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Values

• digest – An instance of <byte-vector>.

<sha512> Class

Superclasses

<hash>

sha512 Function

Signature

sha512 (input) => (digest)

Parameters

• input – An instance of <byte-string>, <buffer> or <byte-vector>.

Values

• digest – An instance of <byte-vector>.