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Source file src/crypto/sha512/sha512.go

Documentation: crypto/sha512

     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  	"errors"
    16  	"hash"
    17  )
    18  
    19  func init() {
    20  	crypto.RegisterHash(crypto.SHA384, New384)
    21  	crypto.RegisterHash(crypto.SHA512, New)
    22  	crypto.RegisterHash(crypto.SHA512_224, New512_224)
    23  	crypto.RegisterHash(crypto.SHA512_256, New512_256)
    24  }
    25  
    26  const (
    27  	// Size is the size, in bytes, of a SHA-512 checksum.
    28  	Size = 64
    29  
    30  	// Size224 is the size, in bytes, of a SHA-512/224 checksum.
    31  	Size224 = 28
    32  
    33  	// Size256 is the size, in bytes, of a SHA-512/256 checksum.
    34  	Size256 = 32
    35  
    36  	// Size384 is the size, in bytes, of a SHA-384 checksum.
    37  	Size384 = 48
    38  
    39  	// BlockSize is the block size, in bytes, of the SHA-512/224,
    40  	// SHA-512/256, SHA-384 and SHA-512 hash functions.
    41  	BlockSize = 128
    42  )
    43  
    44  const (
    45  	chunk     = 128
    46  	init0     = 0x6a09e667f3bcc908
    47  	init1     = 0xbb67ae8584caa73b
    48  	init2     = 0x3c6ef372fe94f82b
    49  	init3     = 0xa54ff53a5f1d36f1
    50  	init4     = 0x510e527fade682d1
    51  	init5     = 0x9b05688c2b3e6c1f
    52  	init6     = 0x1f83d9abfb41bd6b
    53  	init7     = 0x5be0cd19137e2179
    54  	init0_224 = 0x8c3d37c819544da2
    55  	init1_224 = 0x73e1996689dcd4d6
    56  	init2_224 = 0x1dfab7ae32ff9c82
    57  	init3_224 = 0x679dd514582f9fcf
    58  	init4_224 = 0x0f6d2b697bd44da8
    59  	init5_224 = 0x77e36f7304c48942
    60  	init6_224 = 0x3f9d85a86a1d36c8
    61  	init7_224 = 0x1112e6ad91d692a1
    62  	init0_256 = 0x22312194fc2bf72c
    63  	init1_256 = 0x9f555fa3c84c64c2
    64  	init2_256 = 0x2393b86b6f53b151
    65  	init3_256 = 0x963877195940eabd
    66  	init4_256 = 0x96283ee2a88effe3
    67  	init5_256 = 0xbe5e1e2553863992
    68  	init6_256 = 0x2b0199fc2c85b8aa
    69  	init7_256 = 0x0eb72ddc81c52ca2
    70  	init0_384 = 0xcbbb9d5dc1059ed8
    71  	init1_384 = 0x629a292a367cd507
    72  	init2_384 = 0x9159015a3070dd17
    73  	init3_384 = 0x152fecd8f70e5939
    74  	init4_384 = 0x67332667ffc00b31
    75  	init5_384 = 0x8eb44a8768581511
    76  	init6_384 = 0xdb0c2e0d64f98fa7
    77  	init7_384 = 0x47b5481dbefa4fa4
    78  )
    79  
    80  // digest represents the partial evaluation of a checksum.
    81  type digest struct {
    82  	h        [8]uint64
    83  	x        [chunk]byte
    84  	nx       int
    85  	len      uint64
    86  	function crypto.Hash
    87  }
    88  
    89  func (d *digest) Reset() {
    90  	switch d.function {
    91  	case crypto.SHA384:
    92  		d.h[0] = init0_384
    93  		d.h[1] = init1_384
    94  		d.h[2] = init2_384
    95  		d.h[3] = init3_384
    96  		d.h[4] = init4_384
    97  		d.h[5] = init5_384
    98  		d.h[6] = init6_384
    99  		d.h[7] = init7_384
   100  	case crypto.SHA512_224:
   101  		d.h[0] = init0_224
   102  		d.h[1] = init1_224
   103  		d.h[2] = init2_224
   104  		d.h[3] = init3_224
   105  		d.h[4] = init4_224
   106  		d.h[5] = init5_224
   107  		d.h[6] = init6_224
   108  		d.h[7] = init7_224
   109  	case crypto.SHA512_256:
   110  		d.h[0] = init0_256
   111  		d.h[1] = init1_256
   112  		d.h[2] = init2_256
   113  		d.h[3] = init3_256
   114  		d.h[4] = init4_256
   115  		d.h[5] = init5_256
   116  		d.h[6] = init6_256
   117  		d.h[7] = init7_256
   118  	default:
   119  		d.h[0] = init0
   120  		d.h[1] = init1
   121  		d.h[2] = init2
   122  		d.h[3] = init3
   123  		d.h[4] = init4
   124  		d.h[5] = init5
   125  		d.h[6] = init6
   126  		d.h[7] = init7
   127  	}
   128  	d.nx = 0
   129  	d.len = 0
   130  }
   131  
   132  const (
   133  	magic384      = "sha\x04"
   134  	magic512_224  = "sha\x05"
   135  	magic512_256  = "sha\x06"
   136  	magic512      = "sha\x07"
   137  	marshaledSize = len(magic512) + 8*8 + chunk + 8
   138  )
   139  
   140  func (d *digest) MarshalBinary() ([]byte, error) {
   141  	b := make([]byte, 0, marshaledSize)
   142  	switch d.function {
   143  	case crypto.SHA384:
   144  		b = append(b, magic384...)
   145  	case crypto.SHA512_224:
   146  		b = append(b, magic512_224...)
   147  	case crypto.SHA512_256:
   148  		b = append(b, magic512_256...)
   149  	case crypto.SHA512:
   150  		b = append(b, magic512...)
   151  	default:
   152  		return nil, errors.New("crypto/sha512: invalid hash function")
   153  	}
   154  	b = appendUint64(b, d.h[0])
   155  	b = appendUint64(b, d.h[1])
   156  	b = appendUint64(b, d.h[2])
   157  	b = appendUint64(b, d.h[3])
   158  	b = appendUint64(b, d.h[4])
   159  	b = appendUint64(b, d.h[5])
   160  	b = appendUint64(b, d.h[6])
   161  	b = appendUint64(b, d.h[7])
   162  	b = append(b, d.x[:d.nx]...)
   163  	b = b[:len(b)+len(d.x)-int(d.nx)] // already zero
   164  	b = appendUint64(b, d.len)
   165  	return b, nil
   166  }
   167  
   168  func (d *digest) UnmarshalBinary(b []byte) error {
   169  	if len(b) < len(magic512) {
   170  		return errors.New("crypto/sha512: invalid hash state identifier")
   171  	}
   172  	switch {
   173  	case d.function == crypto.SHA384 && string(b[:len(magic384)]) == magic384:
   174  	case d.function == crypto.SHA512_224 && string(b[:len(magic512_224)]) == magic512_224:
   175  	case d.function == crypto.SHA512_256 && string(b[:len(magic512_256)]) == magic512_256:
   176  	case d.function == crypto.SHA512 && string(b[:len(magic512)]) == magic512:
   177  	default:
   178  		return errors.New("crypto/sha512: invalid hash state identifier")
   179  	}
   180  	if len(b) != marshaledSize {
   181  		return errors.New("crypto/sha512: invalid hash state size")
   182  	}
   183  	b = b[len(magic512):]
   184  	b, d.h[0] = consumeUint64(b)
   185  	b, d.h[1] = consumeUint64(b)
   186  	b, d.h[2] = consumeUint64(b)
   187  	b, d.h[3] = consumeUint64(b)
   188  	b, d.h[4] = consumeUint64(b)
   189  	b, d.h[5] = consumeUint64(b)
   190  	b, d.h[6] = consumeUint64(b)
   191  	b, d.h[7] = consumeUint64(b)
   192  	b = b[copy(d.x[:], b):]
   193  	b, d.len = consumeUint64(b)
   194  	d.nx = int(d.len) % chunk
   195  	return nil
   196  }
   197  
   198  func putUint64(x []byte, s uint64) {
   199  	_ = x[7]
   200  	x[0] = byte(s >> 56)
   201  	x[1] = byte(s >> 48)
   202  	x[2] = byte(s >> 40)
   203  	x[3] = byte(s >> 32)
   204  	x[4] = byte(s >> 24)
   205  	x[5] = byte(s >> 16)
   206  	x[6] = byte(s >> 8)
   207  	x[7] = byte(s)
   208  }
   209  
   210  func appendUint64(b []byte, x uint64) []byte {
   211  	var a [8]byte
   212  	putUint64(a[:], x)
   213  	return append(b, a[:]...)
   214  }
   215  
   216  func consumeUint64(b []byte) ([]byte, uint64) {
   217  	_ = b[7]
   218  	x := uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
   219  		uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
   220  	return b[8:], x
   221  }
   222  
   223  // New returns a new hash.Hash computing the SHA-512 checksum.
   224  func New() hash.Hash {
   225  	d := &digest{function: crypto.SHA512}
   226  	d.Reset()
   227  	return d
   228  }
   229  
   230  // New512_224 returns a new hash.Hash computing the SHA-512/224 checksum.
   231  func New512_224() hash.Hash {
   232  	d := &digest{function: crypto.SHA512_224}
   233  	d.Reset()
   234  	return d
   235  }
   236  
   237  // New512_256 returns a new hash.Hash computing the SHA-512/256 checksum.
   238  func New512_256() hash.Hash {
   239  	d := &digest{function: crypto.SHA512_256}
   240  	d.Reset()
   241  	return d
   242  }
   243  
   244  // New384 returns a new hash.Hash computing the SHA-384 checksum.
   245  func New384() hash.Hash {
   246  	d := &digest{function: crypto.SHA384}
   247  	d.Reset()
   248  	return d
   249  }
   250  
   251  func (d *digest) Size() int {
   252  	switch d.function {
   253  	case crypto.SHA512_224:
   254  		return Size224
   255  	case crypto.SHA512_256:
   256  		return Size256
   257  	case crypto.SHA384:
   258  		return Size384
   259  	default:
   260  		return Size
   261  	}
   262  }
   263  
   264  func (d *digest) BlockSize() int { return BlockSize }
   265  
   266  func (d *digest) Write(p []byte) (nn int, err error) {
   267  	nn = len(p)
   268  	d.len += uint64(nn)
   269  	if d.nx > 0 {
   270  		n := copy(d.x[d.nx:], p)
   271  		d.nx += n
   272  		if d.nx == chunk {
   273  			block(d, d.x[:])
   274  			d.nx = 0
   275  		}
   276  		p = p[n:]
   277  	}
   278  	if len(p) >= chunk {
   279  		n := len(p) &^ (chunk - 1)
   280  		block(d, p[:n])
   281  		p = p[n:]
   282  	}
   283  	if len(p) > 0 {
   284  		d.nx = copy(d.x[:], p)
   285  	}
   286  	return
   287  }
   288  
   289  func (d *digest) Sum(in []byte) []byte {
   290  	// Make a copy of d so that caller can keep writing and summing.
   291  	d0 := new(digest)
   292  	*d0 = *d
   293  	hash := d0.checkSum()
   294  	switch d0.function {
   295  	case crypto.SHA384:
   296  		return append(in, hash[:Size384]...)
   297  	case crypto.SHA512_224:
   298  		return append(in, hash[:Size224]...)
   299  	case crypto.SHA512_256:
   300  		return append(in, hash[:Size256]...)
   301  	default:
   302  		return append(in, hash[:]...)
   303  	}
   304  }
   305  
   306  func (d *digest) checkSum() [Size]byte {
   307  	// Padding. Add a 1 bit and 0 bits until 112 bytes mod 128.
   308  	len := d.len
   309  	var tmp [128]byte
   310  	tmp[0] = 0x80
   311  	if len%128 < 112 {
   312  		d.Write(tmp[0 : 112-len%128])
   313  	} else {
   314  		d.Write(tmp[0 : 128+112-len%128])
   315  	}
   316  
   317  	// Length in bits.
   318  	len <<= 3
   319  	putUint64(tmp[0:], 0) // upper 64 bits are always zero, because len variable has type uint64
   320  	putUint64(tmp[8:], len)
   321  	d.Write(tmp[0:16])
   322  
   323  	if d.nx != 0 {
   324  		panic("d.nx != 0")
   325  	}
   326  
   327  	var digest [Size]byte
   328  	putUint64(digest[0:], d.h[0])
   329  	putUint64(digest[8:], d.h[1])
   330  	putUint64(digest[16:], d.h[2])
   331  	putUint64(digest[24:], d.h[3])
   332  	putUint64(digest[32:], d.h[4])
   333  	putUint64(digest[40:], d.h[5])
   334  	if d.function != crypto.SHA384 {
   335  		putUint64(digest[48:], d.h[6])
   336  		putUint64(digest[56:], d.h[7])
   337  	}
   338  
   339  	return digest
   340  }
   341  
   342  // Sum512 returns the SHA512 checksum of the data.
   343  func Sum512(data []byte) [Size]byte {
   344  	d := digest{function: crypto.SHA512}
   345  	d.Reset()
   346  	d.Write(data)
   347  	return d.checkSum()
   348  }
   349  
   350  // Sum384 returns the SHA384 checksum of the data.
   351  func Sum384(data []byte) (sum384 [Size384]byte) {
   352  	d := digest{function: crypto.SHA384}
   353  	d.Reset()
   354  	d.Write(data)
   355  	sum := d.checkSum()
   356  	copy(sum384[:], sum[:Size384])
   357  	return
   358  }
   359  
   360  // Sum512_224 returns the Sum512/224 checksum of the data.
   361  func Sum512_224(data []byte) (sum224 [Size224]byte) {
   362  	d := digest{function: crypto.SHA512_224}
   363  	d.Reset()
   364  	d.Write(data)
   365  	sum := d.checkSum()
   366  	copy(sum224[:], sum[:Size224])
   367  	return
   368  }
   369  
   370  // Sum512_256 returns the Sum512/256 checksum of the data.
   371  func Sum512_256(data []byte) (sum256 [Size256]byte) {
   372  	d := digest{function: crypto.SHA512_256}
   373  	d.Reset()
   374  	d.Write(data)
   375  	sum := d.checkSum()
   376  	copy(sum256[:], sum[:Size256])
   377  	return
   378  }
   379  

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