1/*
2 *  SHA-1 in C
3 *  By Steve Reid <steve@edmweb.com>
4 *  100% Public Domain
5 *
6 *  Version:	$Id: sha1.c,v 1.13 2008/06/05 12:07:22 aland Exp $
7 */
8
9
10#include "fr_sha1.h"
11#include <stdlib.h>
12#include <unistd.h>
13#include <string.h>
14
15#define EXTERN	__private_extern__
16
17#define blk0(i) (block->l[i] = htonl(block->l[i]))
18
19#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
20
21/* blk0() and blk() perform the initial expand. */
22/* I got the idea of expanding during the round function from SSLeay */
23
24#define blk0(i) (block->l[i] = htonl(block->l[i]))
25
26#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
27    ^block->l[(i+2)&15]^block->l[i&15],1))
28
29/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
30#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
31#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
32#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
33#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
34#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
35
36
37/* Hash a single 512-bit block. This is the core of the algorithm. */
38EXTERN
39void fr_SHA1Transform(fr_SHA1_CTX * context, const uint8_t buffer[64])
40{
41  uint32_t a, b, c, d, e;
42  typedef union {
43    uint8_t c[64];
44    uint32_t l[16];
45  } CHAR64LONG16;
46  CHAR64LONG16 *block;
47  CHAR64LONG16 workspace;
48  uint32_t * state = context->state;
49
50    block = &workspace;
51    memcpy(block, buffer, 64);
52    /* Copy context->state[] to working vars */
53    a = state[0];
54    b = state[1];
55    c = state[2];
56    d = state[3];
57    e = state[4];
58    /* 4 rounds of 20 operations each. Loop unrolled. */
59    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);
60    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);
61    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);
62    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);
63    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);
64    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);
65    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);
66    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);
67    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);
68    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);
69    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);
70    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);
71    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);
72    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);
73    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);
74    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);
75    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);
76    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);
77    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);
78    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);
79    /* Add the working vars back into context.state[] */
80    context->state[0] += a;
81    context->state[1] += b;
82    context->state[2] += c;
83    context->state[3] += d;
84    context->state[4] += e;
85    /* Wipe variables */
86    /* a = b = c = d = e = 0; */
87}
88
89
90/* fr_SHA1Init - Initialize new context */
91EXTERN
92void fr_SHA1Init(fr_SHA1_CTX* context)
93{
94    /* SHA1 initialization constants */
95    context->state[0] = 0x67452301;
96    context->state[1] = 0xEFCDAB89;
97    context->state[2] = 0x98BADCFE;
98    context->state[3] = 0x10325476;
99    context->state[4] = 0xC3D2E1F0;
100    context->count[0] = context->count[1] = 0;
101}
102
103
104/* Run your data through this. */
105#if 0
106void fr_SHA1Update(fr_SHA1_CTX* context, const uint8_t* data, unsigned int len)
107{
108unsigned int i, j;
109
110    j = (context->count[0] >> 3) & 63;
111    if ((context->count[0] += len << 3) < (len << 3)) context->count[1]++;
112    context->count[1] += (len >> 29);
113    if ((j + len) > 63) {
114        memcpy(&context->buffer[j], data, (i = 64-j));
115        fr_SHA1Transform(context, context->buffer);
116        for ( ; i + 63 < len; i += 64) {
117            fr_SHA1Transform(context, &data[i]);
118        }
119        j = 0;
120    }
121    else i = 0;
122    memcpy(&context->buffer[j], &data[i], len - i);
123}
124
125
126/* Add padding and return the message digest. */
127
128void fr_SHA1Final(uint8_t digest[20], fr_SHA1_CTX* context)
129{
130uint32_t i, j;
131uint8_t finalcount[8];
132
133    for (i = 0; i < 8; i++) {
134        finalcount[i] = (uint8_t)((context->count[(i >= 4 ? 0 : 1)]
135         >> ((3-(i & 3)) * 8) ) & 255);  /* Endian independent */
136    }
137    fr_SHA1Update(context, (const unsigned char *) "\200", 1);
138    while ((context->count[0] & 504) != 448) {
139        fr_SHA1Update(context, (const unsigned char *) "\0", 1);
140    }
141    fr_SHA1Update(context, finalcount, 8);  /* Should cause a fr_SHA1Transform() */
142    for (i = 0; i < 20; i++) {
143        digest[i] = (uint8_t)
144         ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
145    }
146    /* Wipe variables */
147    i = j = 0;
148    memset(context->buffer, 0, 64);
149    memset(context->state, 0, 20);
150    memset(context->count, 0, 8);
151    memset(&finalcount, 0, 8);
152}
153#endif /* 0 */
154
155EXTERN
156void fr_SHA1FinalNoLen(uint8_t digest[20], fr_SHA1_CTX* context)
157{
158    uint32_t i;
159
160    for (i = 0; i < 20; i++) {
161        digest[i] = (uint8_t)
162         ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
163    }
164
165    /* Wipe variables */
166    memset(context->buffer, 0, 64);
167    memset(context->state, 0, 20);
168    memset(context->count, 0, 8);
169}
170