ObjFW  Check-in [d310aeee30]

Overview
Comment:Rewrite OFSHA1Hash

The old one was based on a public domain implementation, which is
optimized for old compilers and quite unreadable. The new one is written
from scratch and designed to be readable and to exploit optimizations of
modern compilers.

Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA3-256: d310aeee302d5cd61d5b543e4509dd846fe4e7411e3d7742250c12dbd1879a7a
User & Date: js on 2014-08-31 17:59:31
Other Links: manifest | tags
Context
2014-09-01
10:47
OF{MD5,SHA1}Hash: Zero _buffer when done check-in: 23dc2c7ff8 user: js tags: trunk
2014-08-31
17:59
Rewrite OFSHA1Hash check-in: d310aeee30 user: js tags: trunk
17:59
Rewrite OFMD5Hash check-in: c4d2f177cb user: js tags: trunk
Changes

Modified src/OFSHA1Hash.h from [f14987e748] to [19853167ae].

20
21
22
23
24
25
26
27



28
29
30
31
32
 * @class OFSHA1Hash OFSHA1Hash.h ObjFW/OFSHA1Hash.h
 *
 * @brief A class which provides functions to create an SHA1 hash.
 */
@interface OFSHA1Hash: OFObject <OFHash>
{
	uint32_t _state[5];
	uint64_t _count;



	char	 _buffer[64];
	uint8_t	 _digest[20];
	bool	 _calculated;
}
@end







|
>
>
>
|
|
|


20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
 * @class OFSHA1Hash OFSHA1Hash.h ObjFW/OFSHA1Hash.h
 *
 * @brief A class which provides functions to create an SHA1 hash.
 */
@interface OFSHA1Hash: OFObject <OFHash>
{
	uint32_t _state[5];
	uint64_t _bits;
	union {
		uint8_t bytes[64];
		uint32_t words[80];
	} _buffer;
	size_t _bufferLength;
	bool _calculated;
}
@end

Modified src/OFSHA1Hash.m from [8ad65dbc27] to [61d6c59846].

18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36


37

38
39
40
41
42
43
44
45
46
47
48
49

50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74

75





76
77
78

79
80
81
82
83
84
85
86

87
88
89
90
91
92
93
94
95

96

97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133

#include <string.h>

#import "OFSHA1Hash.h"

#import "OFHashAlreadyCalculatedException.h"

/* blk0() and blk() perform the initial expand. */
#ifndef OF_BIG_ENDIAN
#define blk0(i)							\
	(block.l[i] = (OF_ROL(block.l[i], 24) & 0xFF00FF00) |	\
	    (OF_ROL(block.l[i], 8) & 0x00FF00FF))
#else
#define blk0(i) block.l[i]
#endif
#define blk(i) \
	(block.l[i & 15] = OF_ROL(block.l[(i + 13) & 15] ^	\
	    block.l[(i + 8) & 15] ^ block.l[(i + 2) & 15] ^	\
	    block.l[i & 15], 1))




/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
#define R0(v, w, x, y, z, i)						\
	z += ((w & (x ^ y)) ^ y) + blk0(i) + 0x5A827999 + OF_ROL(v, 5);	\
	w = OF_ROL(w, 30);
#define R1(v, w, x, y, z, i)						\
	z += ((w & (x ^ y)) ^ y) + blk(i) +  0x5A827999 + OF_ROL(v, 5);	\
	w = OF_ROL(w, 30);
#define R2(v, w, x, y, z, i)						\
	z += (w ^ x ^ y) + blk(i) + 0x6ED9EBA1 + OF_ROL(v, 5);		\
	w = OF_ROL(w, 30);
#define R3(v, w, x, y, z, i)						     \
	z += (((w | x) & y) | (w & x)) + blk(i) + 0x8F1BBCDC + OF_ROL(v, 5); \

	w = OF_ROL(w, 30);
#define R4(v, w, x, y, z, i)						\
	z += (w ^ x ^ y) + blk(i) + 0xCA62C1D6 + OF_ROL(v, 5);		\
	w = OF_ROL(w, 30);

typedef union {
	char	 c[64];
	uint32_t l[16];
} sha1_c64l16_t;

static inline void
sha1_transform(uint32_t state[5], const char buffer[64])
{
	uint32_t      a, b, c, d, e;
	sha1_c64l16_t block;

	memcpy(block.c, buffer, 64);

	/* Copy state[] to working vars */
	a = state[0];
	b = state[1];
	c = state[2];
	d = state[3];
	e = state[4];


	/* 4 rounds of 20 operations each. Loop unrolled. */





	R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
	R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
	R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);

	R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
	R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
	R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
	R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
	R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
	R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
	R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
	R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);

	R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
	R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
	R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
	R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
	R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
	R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
	R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
	R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
	R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);



	/* Add the working vars back into state[] */
	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;
	state[4] += e;
}

static inline void
sha1_update(uint32_t *state, uint64_t *count, char *buffer,
    const char *buf, size_t length)
{
	size_t i, j;

	j = (size_t)((*count >> 3) & 63);
	*count += (length << 3);

	if ((j + length) > 63) {
		memcpy(&buffer[j], buf, (i = 64 - j));

		sha1_transform(state, buffer);

		for (; i + 63 < length; i += 64)
			sha1_transform(state, &buf[i]);

		j = 0;
	} else
		i = 0;

	memcpy(&buffer[j], &buf[i], length - i);
}

@implementation OFSHA1Hash
+ (size_t)digestSize
{
	return 20;
}







|
<
|
<
<
<
|
<
|
|
<
<
>
>
|
>
|
<
<
|
<
<
|
<
<
<
<
<
>
<
<
<
<

<
<
<
<
<
|
|

|
<
|
<

<
|
|
|
|
|

>
|
>
>
>
>
>
|
|
<
>
|
|
|
|
|
|
|
|
>
|
<
|
|
|
|
|
|
|
>

>
|
|
|
|
|
|
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<
<







18
19
20
21
22
23
24
25

26



27

28
29


30
31
32
33
34


35


36





37




38





39
40
41
42

43

44

45
46
47
48
49
50
51
52
53
54
55
56
57
58
59

60
61
62
63
64
65
66
67
68
69
70

71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
























87
88
89
90
91
92
93

#include <string.h>

#import "OFSHA1Hash.h"

#import "OFHashAlreadyCalculatedException.h"

#define F(a, b, c, d) ((d) ^ ((b) & ((c) ^ (d))))

#define G(a, b, c, d) ((b) ^ (c) ^ (d))



#define H(a, b, c, d) (((b) & (c)) | ((d) & ((b) | (c))))

#define I(a, b, c, d) ((b) ^ (c) ^ (d))



static void
byteSwapVectorIfLE(uint32_t *vector, uint_fast8_t length)
{
	uint_fast8_t i;



	for (i = 0; i < length; i++)


		vector[i] = OF_BSWAP32_IF_LE(vector[i]);





}










static void
processBlock(uint32_t *state, uint32_t *buffer)
{
	uint32_t new[5];

	uint_fast8_t i;



	new[0] = state[0];
	new[1] = state[1];
	new[2] = state[2];
	new[3] = state[3];
	new[4] = state[4];

	byteSwapVectorIfLE(buffer, 16);

	for (i = 16; i < 80; i++) {
		uint32_t tmp = buffer[i - 3] ^ buffer[i - 8] ^
		    buffer[i - 14] ^ buffer[i - 16];
		buffer[i] = OF_ROL(tmp, 1);
	}

#define LOOP_BODY(f, k)							\

	{								\
		uint32_t tmp = OF_ROL(new[0], 5) +			\
		    f(new[0], new[1], new[2], new[3]) +			\
		    new[4] + k + buffer[i];				\
		new[4] = new[3];					\
		new[3] = new[2];					\
		new[2] = OF_ROL(new[1], 30);				\
		new[1] = new[0];					\
		new[0] = tmp;						\
	}


	for (i = 0; i < 20; i++)
		LOOP_BODY(F, 0x5A827999)
	for (; i < 40; i++)
		LOOP_BODY(G, 0x6ED9EBA1)
	for (; i < 60; i++)
		LOOP_BODY(H, 0x8F1BBCDC)
	for (; i < 80; i++)
		LOOP_BODY(I, 0xCA62C1D6)

#undef LOOP_BODY

	state[0] += new[0];
	state[1] += new[1];
	state[2] += new[2];
	state[3] += new[3];
	state[4] += new[4];
























}

@implementation OFSHA1Hash
+ (size_t)digestSize
{
	return 20;
}
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169


170


171


172


173






174

175
176
177
178
179
180
181
182
183
184
185
186
187

188
189
190
191


192


193
194
195
196
197
198
199
200
201
202
	_state[2] = 0x98BADCFE;
	_state[3] = 0x10325476;
	_state[4] = 0xC3D2E1F0;

	return self;
}

- (void)updateWithBuffer: (const void*)buffer
		  length: (size_t)length
{
	if (length == 0)
		return;

	if (_calculated)
		@throw [OFHashAlreadyCalculatedException
		    exceptionWithHash: self];

	sha1_update(_state, &_count, _buffer, buffer, length);
}





- (const uint8_t*)digest


{


	size_t i;






	char finalcount[8];


	if (_calculated)
		return _digest;

	for (i = 0; i < 8; i++)
		/* Endian independent */
		finalcount[i] = (char)((_count >> ((7 - (i & 7)) * 8)) & 255);
	sha1_update(_state, &_count, _buffer, "\200", 1);

	while ((_count & 504) != 448)
		sha1_update(_state, &_count, _buffer, "\0", 1);
	/* Should cause a sha1_transform() */
	sha1_update(_state, &_count, _buffer, finalcount, 8);


	for (i = 0; i < 20; i++)
		_digest[i] = (char)((_state[i >> 2] >>
		    ((3 - (i & 3)) * 8)) & 255);





	_calculated = true;

	return _digest;
}

- (bool)isCalculated
{
	return _calculated;
}
@end







|


|
<





|
|
>
>

>
>
|
>
>
|
>
>
|
>
>
>
>
>
>
|
>
|

|

|
<
<
|

<
|
<
|
>
|
|
<
<
>
>

>
>


|







111
112
113
114
115
116
117
118
119
120
121

122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153


154
155

156

157
158
159
160


161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
	_state[2] = 0x98BADCFE;
	_state[3] = 0x10325476;
	_state[4] = 0xC3D2E1F0;

	return self;
}

- (void)updateWithBuffer: (const void*)buffer_
		  length: (size_t)length
{
	const uint8_t *buffer = buffer_;


	if (_calculated)
		@throw [OFHashAlreadyCalculatedException
		    exceptionWithHash: self];

	_bits += (length * 8);

	while (length > 0) {
		size_t min = 64 - _bufferLength;

		if (min > length)
			min = length;

		memcpy(_buffer.bytes + _bufferLength, buffer, min);
		_bufferLength += min;

		buffer += min;
		length -= min;

		if (_bufferLength == 64) {
			processBlock(_state, _buffer.words);
			_bufferLength = 0;
		}
	}
}

- (const uint8_t*)digest
{
	if (_calculated)
		return (const uint8_t*)_state;

	_buffer.bytes[_bufferLength] = 0x80;


	memset(_buffer.bytes + _bufferLength + 1, 0, 64 - _bufferLength - 1);


	if (_bufferLength >= 56) {

		processBlock(_state, _buffer.words);
		memset(_buffer.bytes, 0, 64);
	}



	_buffer.words[14] = OF_BSWAP32_IF_LE((uint32_t)(_bits >> 32));
	_buffer.words[15] = OF_BSWAP32_IF_LE((uint32_t)(_bits & 0xFFFFFFFF));

	processBlock(_state, _buffer.words);
	byteSwapVectorIfLE(_state, 5);
	_calculated = true;

	return (const uint8_t*)_state;
}

- (bool)isCalculated
{
	return _calculated;
}
@end