Source file src/crypto/sha512/sha512.go

     1	// Copyright 2009 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	
     5	// Package sha512 implements the SHA-384, SHA-512, SHA-512/224, and SHA-512/256
     6	// hash algorithms as defined in FIPS 180-4.
     7	//
     8	// All the hash.Hash implementations returned by this package also
     9	// implement encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
    10	// marshal and unmarshal the internal state of the hash.
    11	package sha512
    12	
    13	import (
    14		"crypto"
    15		"encoding/binary"
    16		"errors"
    17		"hash"
    18	)
    19	
    20	func init() {
    21		crypto.RegisterHash(crypto.SHA384, New384)
    22		crypto.RegisterHash(crypto.SHA512, New)
    23		crypto.RegisterHash(crypto.SHA512_224, New512_224)
    24		crypto.RegisterHash(crypto.SHA512_256, New512_256)
    25	}
    26	
    27	const (
    28		// Size is the size, in bytes, of a SHA-512 checksum.
    29		Size = 64
    30	
    31		// Size224 is the size, in bytes, of a SHA-512/224 checksum.
    32		Size224 = 28
    33	
    34		// Size256 is the size, in bytes, of a SHA-512/256 checksum.
    35		Size256 = 32
    36	
    37		// Size384 is the size, in bytes, of a SHA-384 checksum.
    38		Size384 = 48
    39	
    40		// BlockSize is the block size, in bytes, of the SHA-512/224,
    41		// SHA-512/256, SHA-384 and SHA-512 hash functions.
    42		BlockSize = 128
    43	)
    44	
    45	const (
    46		chunk     = 128
    47		init0     = 0x6a09e667f3bcc908
    48		init1     = 0xbb67ae8584caa73b
    49		init2     = 0x3c6ef372fe94f82b
    50		init3     = 0xa54ff53a5f1d36f1
    51		init4     = 0x510e527fade682d1
    52		init5     = 0x9b05688c2b3e6c1f
    53		init6     = 0x1f83d9abfb41bd6b
    54		init7     = 0x5be0cd19137e2179
    55		init0_224 = 0x8c3d37c819544da2
    56		init1_224 = 0x73e1996689dcd4d6
    57		init2_224 = 0x1dfab7ae32ff9c82
    58		init3_224 = 0x679dd514582f9fcf
    59		init4_224 = 0x0f6d2b697bd44da8
    60		init5_224 = 0x77e36f7304c48942
    61		init6_224 = 0x3f9d85a86a1d36c8
    62		init7_224 = 0x1112e6ad91d692a1
    63		init0_256 = 0x22312194fc2bf72c
    64		init1_256 = 0x9f555fa3c84c64c2
    65		init2_256 = 0x2393b86b6f53b151
    66		init3_256 = 0x963877195940eabd
    67		init4_256 = 0x96283ee2a88effe3
    68		init5_256 = 0xbe5e1e2553863992
    69		init6_256 = 0x2b0199fc2c85b8aa
    70		init7_256 = 0x0eb72ddc81c52ca2
    71		init0_384 = 0xcbbb9d5dc1059ed8
    72		init1_384 = 0x629a292a367cd507
    73		init2_384 = 0x9159015a3070dd17
    74		init3_384 = 0x152fecd8f70e5939
    75		init4_384 = 0x67332667ffc00b31
    76		init5_384 = 0x8eb44a8768581511
    77		init6_384 = 0xdb0c2e0d64f98fa7
    78		init7_384 = 0x47b5481dbefa4fa4
    79	)
    80	
    81	// digest represents the partial evaluation of a checksum.
    82	type digest struct {
    83		h        [8]uint64
    84		x        [chunk]byte
    85		nx       int
    86		len      uint64
    87		function crypto.Hash
    88	}
    89	
    90	func (d *digest) Reset() {
    91		switch d.function {
    92		case crypto.SHA384:
    93			d.h[0] = init0_384
    94			d.h[1] = init1_384
    95			d.h[2] = init2_384
    96			d.h[3] = init3_384
    97			d.h[4] = init4_384
    98			d.h[5] = init5_384
    99			d.h[6] = init6_384
   100			d.h[7] = init7_384
   101		case crypto.SHA512_224:
   102			d.h[0] = init0_224
   103			d.h[1] = init1_224
   104			d.h[2] = init2_224
   105			d.h[3] = init3_224
   106			d.h[4] = init4_224
   107			d.h[5] = init5_224
   108			d.h[6] = init6_224
   109			d.h[7] = init7_224
   110		case crypto.SHA512_256:
   111			d.h[0] = init0_256
   112			d.h[1] = init1_256
   113			d.h[2] = init2_256
   114			d.h[3] = init3_256
   115			d.h[4] = init4_256
   116			d.h[5] = init5_256
   117			d.h[6] = init6_256
   118			d.h[7] = init7_256
   119		default:
   120			d.h[0] = init0
   121			d.h[1] = init1
   122			d.h[2] = init2
   123			d.h[3] = init3
   124			d.h[4] = init4
   125			d.h[5] = init5
   126			d.h[6] = init6
   127			d.h[7] = init7
   128		}
   129		d.nx = 0
   130		d.len = 0
   131	}
   132	
   133	const (
   134		magic384      = "sha\x04"
   135		magic512_224  = "sha\x05"
   136		magic512_256  = "sha\x06"
   137		magic512      = "sha\x07"
   138		marshaledSize = len(magic512) + 8*8 + chunk + 8
   139	)
   140	
   141	func (d *digest) MarshalBinary() ([]byte, error) {
   142		b := make([]byte, 0, marshaledSize)
   143		switch d.function {
   144		case crypto.SHA384:
   145			b = append(b, magic384...)
   146		case crypto.SHA512_224:
   147			b = append(b, magic512_224...)
   148		case crypto.SHA512_256:
   149			b = append(b, magic512_256...)
   150		case crypto.SHA512:
   151			b = append(b, magic512...)
   152		default:
   153			return nil, errors.New("crypto/sha512: invalid hash function")
   154		}
   155		b = appendUint64(b, d.h[0])
   156		b = appendUint64(b, d.h[1])
   157		b = appendUint64(b, d.h[2])
   158		b = appendUint64(b, d.h[3])
   159		b = appendUint64(b, d.h[4])
   160		b = appendUint64(b, d.h[5])
   161		b = appendUint64(b, d.h[6])
   162		b = appendUint64(b, d.h[7])
   163		b = append(b, d.x[:d.nx]...)
   164		b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
   165		b = appendUint64(b, d.len)
   166		return b, nil
   167	}
   168	
   169	func (d *digest) UnmarshalBinary(b []byte) error {
   170		if len(b) < len(magic512) {
   171			return errors.New("crypto/sha512: invalid hash state identifier")
   172		}
   173		switch {
   174		case d.function == crypto.SHA384 && string(b[:len(magic384)]) == magic384:
   175		case d.function == crypto.SHA512_224 && string(b[:len(magic512_224)]) == magic512_224:
   176		case d.function == crypto.SHA512_256 && string(b[:len(magic512_256)]) == magic512_256:
   177		case d.function == crypto.SHA512 && string(b[:len(magic512)]) == magic512:
   178		default:
   179			return errors.New("crypto/sha512: invalid hash state identifier")
   180		}
   181		if len(b) != marshaledSize {
   182			return errors.New("crypto/sha512: invalid hash state size")
   183		}
   184		b = b[len(magic512):]
   185		b, d.h[0] = consumeUint64(b)
   186		b, d.h[1] = consumeUint64(b)
   187		b, d.h[2] = consumeUint64(b)
   188		b, d.h[3] = consumeUint64(b)
   189		b, d.h[4] = consumeUint64(b)
   190		b, d.h[5] = consumeUint64(b)
   191		b, d.h[6] = consumeUint64(b)
   192		b, d.h[7] = consumeUint64(b)
   193		b = b[copy(d.x[:], b):]
   194		b, d.len = consumeUint64(b)
   195		d.nx = int(d.len % chunk)
   196		return nil
   197	}
   198	
   199	func appendUint64(b []byte, x uint64) []byte {
   200		var a [8]byte
   201		binary.BigEndian.PutUint64(a[:], x)
   202		return append(b, a[:]...)
   203	}
   204	
   205	func consumeUint64(b []byte) ([]byte, uint64) {
   206		_ = b[7]
   207		x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
   208			uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
   209		return b[8:], x
   210	}
   211	
   212	// New returns a new hash.Hash computing the SHA-512 checksum.
   213	func New() hash.Hash {
   214		d := &digest{function: crypto.SHA512}
   215		d.Reset()
   216		return d
   217	}
   218	
   219	// New512_224 returns a new hash.Hash computing the SHA-512/224 checksum.
   220	func New512_224() hash.Hash {
   221		d := &digest{function: crypto.SHA512_224}
   222		d.Reset()
   223		return d
   224	}
   225	
   226	// New512_256 returns a new hash.Hash computing the SHA-512/256 checksum.
   227	func New512_256() hash.Hash {
   228		d := &digest{function: crypto.SHA512_256}
   229		d.Reset()
   230		return d
   231	}
   232	
   233	// New384 returns a new hash.Hash computing the SHA-384 checksum.
   234	func New384() hash.Hash {
   235		d := &digest{function: crypto.SHA384}
   236		d.Reset()
   237		return d
   238	}
   239	
   240	func (d *digest) Size() int {
   241		switch d.function {
   242		case crypto.SHA512_224:
   243			return Size224
   244		case crypto.SHA512_256:
   245			return Size256
   246		case crypto.SHA384:
   247			return Size384
   248		default:
   249			return Size
   250		}
   251	}
   252	
   253	func (d *digest) BlockSize() int { return BlockSize }
   254	
   255	func (d *digest) Write(p []byte) (nn int, err error) {
   256		nn = len(p)
   257		d.len += uint64(nn)
   258		if d.nx > 0 {
   259			n := copy(d.x[d.nx:], p)
   260			d.nx += n
   261			if d.nx == chunk {
   262				block(d, d.x[:])
   263				d.nx = 0
   264			}
   265			p = p[n:]
   266		}
   267		if len(p) >= chunk {
   268			n := len(p) &^ (chunk - 1)
   269			block(d, p[:n])
   270			p = p[n:]
   271		}
   272		if len(p) > 0 {
   273			d.nx = copy(d.x[:], p)
   274		}
   275		return
   276	}
   277	
   278	func (d *digest) Sum(in []byte) []byte {
   279		// Make a copy of d so that caller can keep writing and summing.
   280		d0 := new(digest)
   281		*d0 = *d
   282		hash := d0.checkSum()
   283		switch d0.function {
   284		case crypto.SHA384:
   285			return append(in, hash[:Size384]...)
   286		case crypto.SHA512_224:
   287			return append(in, hash[:Size224]...)
   288		case crypto.SHA512_256:
   289			return append(in, hash[:Size256]...)
   290		default:
   291			return append(in, hash[:]...)
   292		}
   293	}
   294	
   295	func (d *digest) checkSum() [Size]byte {
   296		// Padding. Add a 1 bit and 0 bits until 112 bytes mod 128.
   297		len := d.len
   298		var tmp [128]byte
   299		tmp[0] = 0x80
   300		if len%128 < 112 {
   301			d.Write(tmp[0 : 112-len%128])
   302		} else {
   303			d.Write(tmp[0 : 128+112-len%128])
   304		}
   305	
   306		// Length in bits.
   307		len <<= 3
   308		binary.BigEndian.PutUint64(tmp[0:], 0) // upper 64 bits are always zero, because len variable has type uint64
   309		binary.BigEndian.PutUint64(tmp[8:], len)
   310		d.Write(tmp[0:16])
   311	
   312		if d.nx != 0 {
   313			panic("d.nx != 0")
   314		}
   315	
   316		var digest [Size]byte
   317		binary.BigEndian.PutUint64(digest[0:], d.h[0])
   318		binary.BigEndian.PutUint64(digest[8:], d.h[1])
   319		binary.BigEndian.PutUint64(digest[16:], d.h[2])
   320		binary.BigEndian.PutUint64(digest[24:], d.h[3])
   321		binary.BigEndian.PutUint64(digest[32:], d.h[4])
   322		binary.BigEndian.PutUint64(digest[40:], d.h[5])
   323		if d.function != crypto.SHA384 {
   324			binary.BigEndian.PutUint64(digest[48:], d.h[6])
   325			binary.BigEndian.PutUint64(digest[56:], d.h[7])
   326		}
   327	
   328		return digest
   329	}
   330	
   331	// Sum512 returns the SHA512 checksum of the data.
   332	func Sum512(data []byte) [Size]byte {
   333		d := digest{function: crypto.SHA512}
   334		d.Reset()
   335		d.Write(data)
   336		return d.checkSum()
   337	}
   338	
   339	// Sum384 returns the SHA384 checksum of the data.
   340	func Sum384(data []byte) (sum384 [Size384]byte) {
   341		d := digest{function: crypto.SHA384}
   342		d.Reset()
   343		d.Write(data)
   344		sum := d.checkSum()
   345		copy(sum384[:], sum[:Size384])
   346		return
   347	}
   348	
   349	// Sum512_224 returns the Sum512/224 checksum of the data.
   350	func Sum512_224(data []byte) (sum224 [Size224]byte) {
   351		d := digest{function: crypto.SHA512_224}
   352		d.Reset()
   353		d.Write(data)
   354		sum := d.checkSum()
   355		copy(sum224[:], sum[:Size224])
   356		return
   357	}
   358	
   359	// Sum512_256 returns the Sum512/256 checksum of the data.
   360	func Sum512_256(data []byte) (sum256 [Size256]byte) {
   361		d := digest{function: crypto.SHA512_256}
   362		d.Reset()
   363		d.Write(data)
   364		sum := d.checkSum()
   365		copy(sum256[:], sum[:Size256])
   366		return
   367	}
   368	

View as plain text