1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
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
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
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
|
/* sha1.c - an implementation of Secure Hash Algorithm 1 (SHA1)
* based on RFC 3174.
*
* Copyright: 2008-2012 Aleksey Kravchenko <rhash.admin@gmail.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. Use this program at your own risk!
*/
#include <string.h>
#include "byte_order.h"
#include "sha1.h"
/**
* Initialize context before calculaing hash.
*
* @param ctx context to initialize
*/
void rhash_sha1_init(sha1_ctx *ctx)
{
ctx->length = 0;
/* initialize algorithm state */
ctx->hash[0] = 0x67452301;
ctx->hash[1] = 0xefcdab89;
ctx->hash[2] = 0x98badcfe;
ctx->hash[3] = 0x10325476;
ctx->hash[4] = 0xc3d2e1f0;
}
/**
* The core transformation. Process a 512-bit block.
* The function has been taken from RFC 3174 with little changes.
*
* @param hash algorithm state
* @param block the message block to process
*/
static void rhash_sha1_process_block(unsigned* hash, const unsigned* block)
{
int t; /* Loop counter */
uint32_t temp; /* Temporary word value */
uint32_t W[80]; /* Word sequence */
uint32_t A, B, C, D, E; /* Word buffers */
/* initialize the first 16 words in the array W */
for (t = 0; t < 16; t++) {
/* note: it is much faster to apply be2me here, then using be32_copy */
W[t] = be2me_32(block[t]);
}
/* initialize the rest */
for (t = 16; t < 80; t++) {
W[t] = ROTL32(W[t - 3] ^ W[t - 8] ^ W[t - 14] ^ W[t - 16], 1);
}
A = hash[0];
B = hash[1];
C = hash[2];
D = hash[3];
E = hash[4];
for (t = 0; t < 20; t++) {
/* the following is faster than ((B & C) | ((~B) & D)) */
temp = ROTL32(A, 5) + (((C ^ D) & B) ^ D)
+ E + W[t] + 0x5A827999;
E = D;
D = C;
C = ROTL32(B, 30);
B = A;
A = temp;
}
for (t = 20; t < 40; t++) {
temp = ROTL32(A, 5) + (B ^ C ^ D) + E + W[t] + 0x6ED9EBA1;
E = D;
D = C;
C = ROTL32(B, 30);
B = A;
A = temp;
}
for (t = 40; t < 60; t++) {
temp = ROTL32(A, 5) + ((B & C) | (B & D) | (C & D))
+ E + W[t] + 0x8F1BBCDC;
E = D;
D = C;
C = ROTL32(B, 30);
B = A;
A = temp;
}
for (t = 60; t < 80; t++) {
temp = ROTL32(A, 5) + (B ^ C ^ D) + E + W[t] + 0xCA62C1D6;
E = D;
D = C;
C = ROTL32(B, 30);
B = A;
A = temp;
}
hash[0] += A;
hash[1] += B;
hash[2] += C;
hash[3] += D;
hash[4] += E;
}
/**
* Calculate message hash.
* Can be called repeatedly with chunks of the message to be hashed.
*
* @param ctx the algorithm context containing current hashing state
* @param msg message chunk
* @param size length of the message chunk
*/
void rhash_sha1_update(sha1_ctx *ctx, const unsigned char* msg, size_t size)
{
unsigned index = (unsigned)ctx->length & 63;
ctx->length += size;
/* fill partial block */
if (index) {
unsigned left = sha1_block_size - index;
memcpy(ctx->message + index, msg, (size < left ? size : left));
if (size < left) return;
/* process partial block */
rhash_sha1_process_block(ctx->hash, (unsigned*)ctx->message);
msg += left;
size -= left;
}
while (size >= sha1_block_size) {
unsigned* aligned_message_block;
if (IS_ALIGNED_32(msg)) {
/* the most common case is processing of an already aligned message
without copying it */
aligned_message_block = (unsigned*)msg;
} else {
memcpy(ctx->message, msg, sha1_block_size);
aligned_message_block = (unsigned*)ctx->message;
}
rhash_sha1_process_block(ctx->hash, aligned_message_block);
msg += sha1_block_size;
size -= sha1_block_size;
}
if (size) {
/* save leftovers */
memcpy(ctx->message, msg, size);
}
}
/**
* Store calculated hash into the given array.
*
* @param ctx the algorithm context containing current hashing state
* @param result calculated hash in binary form
*/
void rhash_sha1_final(sha1_ctx *ctx, unsigned char* result)
{
unsigned index = (unsigned)ctx->length & 63;
unsigned* msg32 = (unsigned*)ctx->message;
/* pad message and run for last block */
ctx->message[index++] = 0x80;
while ((index & 3) != 0) {
ctx->message[index++] = 0;
}
index >>= 2;
/* if no room left in the message to store 64-bit message length */
if (index > 14) {
/* then fill the rest with zeros and process it */
while (index < 16) {
msg32[index++] = 0;
}
rhash_sha1_process_block(ctx->hash, msg32);
index = 0;
}
while (index < 14) {
msg32[index++] = 0;
}
msg32[14] = be2me_32( (unsigned)(ctx->length >> 29) );
msg32[15] = be2me_32( (unsigned)(ctx->length << 3) );
rhash_sha1_process_block(ctx->hash, msg32);
if (result) be32_copy(result, 0, &ctx->hash, sha1_hash_size);
}
|
