1// Copyright 2014 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5package sha3
6
7// This file provides functions for creating instances of the SHA-3
8// and SHAKE hash functions, as well as utility functions for hashing
9// bytes.
10
11import (
12	"hash"
13)
14
15// New224 creates a new SHA3-224 hash.
16// Its generic security strength is 224 bits against preimage attacks,
17// and 112 bits against collision attacks.
18func New224() hash.Hash {
19	return new224()
20}
21
22// New256 creates a new SHA3-256 hash.
23// Its generic security strength is 256 bits against preimage attacks,
24// and 128 bits against collision attacks.
25func New256() hash.Hash {
26	return new256()
27}
28
29// New384 creates a new SHA3-384 hash.
30// Its generic security strength is 384 bits against preimage attacks,
31// and 192 bits against collision attacks.
32func New384() hash.Hash {
33	return new384()
34}
35
36// New512 creates a new SHA3-512 hash.
37// Its generic security strength is 512 bits against preimage attacks,
38// and 256 bits against collision attacks.
39func New512() hash.Hash {
40	return new512()
41}
42
43func new224Generic() *state {
44	return &state{rate: 144, outputLen: 28, dsbyte: 0x06}
45}
46
47func new256Generic() *state {
48	return &state{rate: 136, outputLen: 32, dsbyte: 0x06}
49}
50
51func new384Generic() *state {
52	return &state{rate: 104, outputLen: 48, dsbyte: 0x06}
53}
54
55func new512Generic() *state {
56	return &state{rate: 72, outputLen: 64, dsbyte: 0x06}
57}
58
59// NewLegacyKeccak256 creates a new Keccak-256 hash.
60//
61// Only use this function if you require compatibility with an existing cryptosystem
62// that uses non-standard padding. All other users should use New256 instead.
63func NewLegacyKeccak256() hash.Hash { return &state{rate: 136, outputLen: 32, dsbyte: 0x01} }
64
65// NewLegacyKeccak512 creates a new Keccak-512 hash.
66//
67// Only use this function if you require compatibility with an existing cryptosystem
68// that uses non-standard padding. All other users should use New512 instead.
69func NewLegacyKeccak512() hash.Hash { return &state{rate: 72, outputLen: 64, dsbyte: 0x01} }
70
71// Sum224 returns the SHA3-224 digest of the data.
72func Sum224(data []byte) (digest [28]byte) {
73	h := New224()
74	h.Write(data)
75	h.Sum(digest[:0])
76	return
77}
78
79// Sum256 returns the SHA3-256 digest of the data.
80func Sum256(data []byte) (digest [32]byte) {
81	h := New256()
82	h.Write(data)
83	h.Sum(digest[:0])
84	return
85}
86
87// Sum384 returns the SHA3-384 digest of the data.
88func Sum384(data []byte) (digest [48]byte) {
89	h := New384()
90	h.Write(data)
91	h.Sum(digest[:0])
92	return
93}
94
95// Sum512 returns the SHA3-512 digest of the data.
96func Sum512(data []byte) (digest [64]byte) {
97	h := New512()
98	h.Write(data)
99	h.Sum(digest[:0])
100	return
101}
102