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) [Size384]byte {
   341  	d := digest{function: crypto.SHA384}
   342  	d.Reset()
   343  	d.Write(data)
   344  	sum := d.checkSum()
   345  	ap := (*[Size384]byte)(sum[:])
   346  	return *ap
   347  }
   348  
   349  // Sum512_224 returns the Sum512/224 checksum of the data.
   350  func Sum512_224(data []byte) [Size224]byte {
   351  	d := digest{function: crypto.SHA512_224}
   352  	d.Reset()
   353  	d.Write(data)
   354  	sum := d.checkSum()
   355  	ap := (*[Size224]byte)(sum[:])
   356  	return *ap
   357  }
   358  
   359  // Sum512_256 returns the Sum512/256 checksum of the data.
   360  func Sum512_256(data []byte) [Size256]byte {
   361  	d := digest{function: crypto.SHA512_256}
   362  	d.Reset()
   363  	d.Write(data)
   364  	sum := d.checkSum()
   365  	ap := (*[Size256]byte)(sum[:])
   366  	return *ap
   367  }
   368
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