xref: /openbsd/lib/libc/hash/sha1.c (revision 73471bf0)
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 
45 typedef 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  */
53 void
54 SHA1Transform(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 }
101 DEF_WEAK(SHA1Transform);
102 
103 
104 /*
105  * SHA1Init - Initialize new context
106  */
107 void
108 SHA1Init(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 }
119 DEF_WEAK(SHA1Init);
120 
121 
122 /*
123  * Run your data through this.
124  */
125 void
126 SHA1Update(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 }
143 DEF_WEAK(SHA1Update);
144 
145 
146 /*
147  * Add padding and return the message digest.
148  */
149 void
150 SHA1Pad(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 }
164 DEF_WEAK(SHA1Pad);
165 
166 void
167 SHA1Final(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 }
178 DEF_WEAK(SHA1Final);
179