1/*	$OpenBSD: sha1.c,v 1.27 2019/06/07 22:56:36 dtucker Exp $	*/
2
3/*
4 * SHA-1 in C
5 * By Steve Reid <steve@edmweb.com>
6 * 100% Public Domain
7 *
8 * Test Vectors (from FIPS PUB 180-1)
9 * "abc"
10 *   A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
11 * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
12 *   84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
13 * A million repetitions of "a"
14 *   34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
15 */
16
17#include <sys/types.h>
18#include <string.h>
19#include <sha1.h>
20
21#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
22
23/*
24 * blk0() and blk() perform the initial expand.
25 * I got the idea of expanding during the round function from SSLeay
26 */
27#if BYTE_ORDER == LITTLE_ENDIAN
28# define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \
29    |(rol(block->l[i],8)&0x00FF00FF))
30#else
31# define blk0(i) block->l[i]
32#endif
33#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
34    ^block->l[(i+2)&15]^block->l[i&15],1))
35
36/*
37 * (R0+R1), R2, R3, R4 are the different operations (rounds) used in SHA1
38 */
39#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
40#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
41#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
42#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
43#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
44
45typedef union {
46	u_int8_t c[64];
47	u_int32_t l[16];
48} CHAR64LONG16;
49
50/*
51 * Hash a single 512-bit block. This is the core of the algorithm.
52 */
53void
54SHA1Transform(u_int32_t state[5], const u_int8_t buffer[SHA1_BLOCK_LENGTH])
55{
56	u_int32_t a, b, c, d, e;
57	u_int8_t workspace[SHA1_BLOCK_LENGTH];
58	CHAR64LONG16 *block = (CHAR64LONG16 *)workspace;
59
60	(void)memcpy(block, buffer, SHA1_BLOCK_LENGTH);
61
62	/* Copy context->state[] to working vars */
63	a = state[0];
64	b = state[1];
65	c = state[2];
66	d = state[3];
67	e = state[4];
68
69	/* 4 rounds of 20 operations each. Loop unrolled. */
70	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);
71	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);
72	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);
73	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);
74	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);
75	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);
76	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);
77	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);
78	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);
79	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);
80	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);
81	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);
82	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);
83	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);
84	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);
85	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);
86	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);
87	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);
88	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);
89	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);
90
91	/* Add the working vars back into context.state[] */
92	state[0] += a;
93	state[1] += b;
94	state[2] += c;
95	state[3] += d;
96	state[4] += e;
97
98	/* Wipe variables */
99	a = b = c = d = e = 0;
100}
101DEF_WEAK(SHA1Transform);
102
103
104/*
105 * SHA1Init - Initialize new context
106 */
107void
108SHA1Init(SHA1_CTX *context)
109{
110
111	/* SHA1 initialization constants */
112	context->count = 0;
113	context->state[0] = 0x67452301;
114	context->state[1] = 0xEFCDAB89;
115	context->state[2] = 0x98BADCFE;
116	context->state[3] = 0x10325476;
117	context->state[4] = 0xC3D2E1F0;
118}
119DEF_WEAK(SHA1Init);
120
121
122/*
123 * Run your data through this.
124 */
125void
126SHA1Update(SHA1_CTX *context, const u_int8_t *data, size_t len)
127{
128	size_t i, j;
129
130	j = (size_t)((context->count >> 3) & 63);
131	context->count += ((u_int64_t)len << 3);
132	if ((j + len) > 63) {
133		(void)memcpy(&context->buffer[j], data, (i = 64-j));
134		SHA1Transform(context->state, context->buffer);
135		for ( ; i + 63 < len; i += 64)
136			SHA1Transform(context->state, (u_int8_t *)&data[i]);
137		j = 0;
138	} else {
139		i = 0;
140	}
141	(void)memcpy(&context->buffer[j], &data[i], len - i);
142}
143DEF_WEAK(SHA1Update);
144
145
146/*
147 * Add padding and return the message digest.
148 */
149void
150SHA1Pad(SHA1_CTX *context)
151{
152	u_int8_t finalcount[8];
153	u_int i;
154
155	for (i = 0; i < 8; i++) {
156		finalcount[i] = (u_int8_t)((context->count >>
157		    ((7 - (i & 7)) * 8)) & 255);	/* Endian independent */
158	}
159	SHA1Update(context, (u_int8_t *)"\200", 1);
160	while ((context->count & 504) != 448)
161		SHA1Update(context, (u_int8_t *)"\0", 1);
162	SHA1Update(context, finalcount, 8); /* Should cause a SHA1Transform() */
163}
164DEF_WEAK(SHA1Pad);
165
166void
167SHA1Final(u_int8_t digest[SHA1_DIGEST_LENGTH], SHA1_CTX *context)
168{
169	u_int i;
170
171	SHA1Pad(context);
172	for (i = 0; i < SHA1_DIGEST_LENGTH; i++) {
173		digest[i] = (u_int8_t)
174		   ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
175	}
176	explicit_bzero(context, sizeof(*context));
177}
178DEF_WEAK(SHA1Final);
179