aboutsummaryrefslogtreecommitdiff
path: root/toys/sha1.c
blob: 4180f39c931d3e3ede72ef3913e86181ced5c508 (plain)
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
197
198
199
200
201
202
203
204
205
/*
 * Based on the public domain SHA-1 in C by Steve Reid <steve@edmweb.com>
 * from http://www.mirrors.wiretapped.net/security/cryptography/hashes/sha1/
 */

/* #define LITTLE_ENDIAN * This should be #define'd if true. */
/* #define SHA1HANDSOFF * Copies data before messing with it. */
#define	LITTLE_ENDIAN

#include <stdio.h>
#include <string.h>
#include <inttypes.h>

struct sha1 {
	uint32_t state[5];
	uint32_t count[2];
	unsigned char buffer[64];
};

void sha1_init(struct sha1 *this);
void sha1_transform(unsigned int state[5], unsigned char buffer[64]);
void sha1_update(struct sha1 *this, unsigned char *data, unsigned int len);
void sha1_final(struct sha1 *this, unsigned char digest[20]);

#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

/* blk0() and blk() perform the initial expand. */
/* I got the idea of expanding during the round function from SSLeay */
#ifdef LITTLE_ENDIAN
#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
	|(rol(block->l[i],8)&0x00FF00FF))
#else
#define blk0(i) block->l[i]
#endif
#define blk(i) (block->l[i&15] = 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+rol(v,5);w=rol(w,30);
#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);

void printy(unsigned char *this)
{
	int i;

	for (i = 0; i < 20; i++) printf("%02x", this[i]);
	putchar('\n');
}

/* Hash a single 512-bit block. This is the core of the algorithm. */

void sha1_transform(unsigned int state[5], unsigned char buffer[64])
{
	unsigned int a, b, c, d, e;

	typedef union {
		unsigned char c[64];
		unsigned int l[16];
	} CHAR64LONG16;
	CHAR64LONG16* block;
	unsigned char workspace[64];
	block = (CHAR64LONG16*)workspace;
	memcpy(block, buffer, 64);

	/* Copy context->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 context.state[] */
	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;
	state[4] += e;

	/* Wipe variables */
	a = b = c = d = e = 0;
}


/* SHA1Init - Initialize new context */

void sha1_init(struct sha1 *this)
{
	/* SHA1 initialization constants */
	this->state[0] = 0x67452301;
	this->state[1] = 0xEFCDAB89;
	this->state[2] = 0x98BADCFE;
	this->state[3] = 0x10325476;
	this->state[4] = 0xC3D2E1F0;
	this->count[0] = this->count[1] = 0;
}

/* Run your data through this function. */

void sha1_update(struct sha1 *this, unsigned char *data, unsigned int len)
{
	unsigned int i, j;

	j = (this->count[0] >> 3) & 63;
	if ((this->count[0] += len << 3) < (len << 3)) this->count[1]++;
	this->count[1] += (len >> 29);
	if ((j + len) > 63) {
		memcpy(this->buffer + j, data, (i = 64-j));
		sha1_transform(this->state, this->buffer);
		for ( ; i + 63 < len; i += 64)
			sha1_transform(this->state, data + i);
		j = 0;
	}
	else i = 0;
	memcpy(this->buffer + j, data + i, len - i);
}


/* Add padding and return the message digest. */

void sha1_final(struct sha1 *this, unsigned char digest[20])
{
	unsigned int i, j;
	unsigned char finalcount[8];

	for (i = 0; i < 8; i++) {
		finalcount[i] = (unsigned char)((this->count[(i >= 4 ? 0 : 1)]
		 >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
	}
	sha1_update(this, (unsigned char *)"\200", 1);
	while ((this->count[0] & 504) != 448) {
		sha1_update(this, (unsigned char *)"\0", 1);
	}
	sha1_update(this, finalcount, 8);  /* Should cause a SHA1Transform() */
	for (i = 0; i < 20; i++) {
		digest[i] = (unsigned char)
		 ((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
	}
	/* Wipe variables */
	i = j = 0;
	memset(this->buffer, 0, 64);
	memset(this->state, 0, 20);
	memset(this->count, 0, 8);
	memset(finalcount, 0, 8);
	/* make SHA1Transform overwrite it's own static vars */
	sha1_transform(this->state, this->buffer);
}


/*************************************************************/


int main(int argc, char** argv)
{
	int i, j;
	struct sha1 this;
	unsigned char digest[20], buffer[16384];
	FILE* file;

	if (argc > 2) {
		puts("Public domain SHA-1 implementation - by Steve Reid <steve@edmweb.com>");
		puts("Produces the SHA-1 hash of a file, or stdin if no file is specified.");
		exit(0);
	}
	if (argc < 2) {
		file = stdin;
	}
	else {
		if (!(file = fopen(argv[1], "rb"))) {
			fputs("Unable to open file.", stderr);
			exit(-1);
		}
	}
	sha1_init(&this);
	while (!feof(file)) {  /* note: what if ferror(file) */
		i = fread(buffer, 1, 16384, file);
		sha1_update(&this, buffer, i);
	}
	sha1_final(&this, digest);
	fclose(file);
	printy(digest);
	exit(0);
}