separated sha1_prf implementation from sha1_hasher
[strongswan.git] / src / libstrongswan / plugins / sha1 / sha1_hasher.c
1 /*
2 * Copyright (C) 2005-2006 Martin Willi
3 * Copyright (C) 2005 Jan Hutter
4 * Hochschule fuer Technik Rapperswil
5 *
6 * Ported from Steve Reid's <steve@edmweb.com> implementation
7 * "SHA1 in C" found in strongSwan.
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2 of the License, or (at your
12 * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
16 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 * for more details.
18 *
19 * $Id$
20 */
21
22 #include <string.h>
23 #include <arpa/inet.h>
24
25 #include "sha1_hasher.h"
26
27 /*
28 * ugly macro stuff
29 */
30 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
31
32 #if BYTE_ORDER == LITTLE_ENDIAN
33 #define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) |(rol(block->l[i],8)&0x00FF00FF))
34 #elif BYTE_ORDER == BIG_ENDIAN
35 #define blk0(i) block->l[i]
36 #else
37 #error "Endianness not defined!"
38 #endif
39 #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))
40
41 /* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */
42 #define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30);
43 #define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
44 #define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
45 #define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
46 #define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);
47
48
49 typedef struct private_sha1_hasher_t private_sha1_hasher_t;
50
51 /**
52 * Private data structure with hasing context.
53 */
54 struct private_sha1_hasher_t {
55 /**
56 * Public interface for this hasher.
57 */
58 sha1_hasher_t public;
59
60 /*
61 * State of the hasher. Shared with sha1_prf.c, do not change it!!!
62 */
63 u_int32_t state[5];
64 u_int32_t count[2];
65 u_int8_t buffer[64];
66 };
67
68 /*
69 * Hash a single 512-bit block. This is the core of the algorithm. *
70 */
71 static void SHA1Transform(u_int32_t state[5], const unsigned char buffer[64])
72 {
73 u_int32_t a, b, c, d, e;
74 typedef union {
75 u_int8_t c[64];
76 u_int32_t l[16];
77 } CHAR64LONG16;
78 CHAR64LONG16 block[1]; /* use array to appear as a pointer */
79 memcpy(block, buffer, 64);
80
81 /* Copy context->state[] to working vars */
82 a = state[0];
83 b = state[1];
84 c = state[2];
85 d = state[3];
86 e = state[4];
87 /* 4 rounds of 20 operations each. Loop unrolled. */
88 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);
89 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);
90 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);
91 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);
92 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);
93 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);
94 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);
95 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);
96 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);
97 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);
98 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);
99 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);
100 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);
101 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);
102 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);
103 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);
104 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);
105 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);
106 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);
107 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);
108 /* Add the working vars back into context.state[] */
109 state[0] += a;
110 state[1] += b;
111 state[2] += c;
112 state[3] += d;
113 state[4] += e;
114 /* Wipe variables */
115 a = b = c = d = e = 0;
116 memset(block, '\0', sizeof(block));
117 }
118
119 /**
120 * Run your data through this. Also used in sha1_prf.
121 */
122 void SHA1Update(private_sha1_hasher_t* this, u_int8_t *data, u_int32_t len)
123 {
124 u_int32_t i;
125 u_int32_t j;
126
127 j = this->count[0];
128 if ((this->count[0] += len << 3) < j)
129 {
130 this->count[1]++;
131 }
132 this->count[1] += (len>>29);
133 j = (j >> 3) & 63;
134 if ((j + len) > 63)
135 {
136 memcpy(&this->buffer[j], data, (i = 64-j));
137 SHA1Transform(this->state, this->buffer);
138 for ( ; i + 63 < len; i += 64)
139 {
140 SHA1Transform(this->state, &data[i]);
141 }
142 j = 0;
143 }
144 else
145 {
146 i = 0;
147 }
148 memcpy(&this->buffer[j], &data[i], len - i);
149 }
150
151
152 /*
153 * Add padding and return the message digest.
154 */
155 static void SHA1Final(private_sha1_hasher_t *this, u_int8_t *digest)
156 {
157 u_int32_t i;
158 u_int8_t finalcount[8];
159 u_int8_t c;
160
161 for (i = 0; i < 8; i++)
162 {
163 finalcount[i] = (u_int8_t)((this->count[(i >= 4 ? 0 : 1)]
164 >> ((3-(i & 3)) * 8) ) & 255); /* Endian independent */
165 }
166 c = 0200;
167 SHA1Update(this, &c, 1);
168 while ((this->count[0] & 504) != 448)
169 {
170 c = 0000;
171 SHA1Update(this, &c, 1);
172 }
173 SHA1Update(this, finalcount, 8); /* Should cause a SHA1Transform() */
174 for (i = 0; i < 20; i++)
175 {
176 digest[i] = (u_int8_t)((this->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
177 }
178 }
179
180 /**
181 * Implementation of hasher_t.reset.
182 */
183 static void reset(private_sha1_hasher_t *this)
184 {
185 this->state[0] = 0x67452301;
186 this->state[1] = 0xEFCDAB89;
187 this->state[2] = 0x98BADCFE;
188 this->state[3] = 0x10325476;
189 this->state[4] = 0xC3D2E1F0;
190 this->count[0] = 0;
191 this->count[1] = 0;
192 }
193
194 /**
195 * Implementation of hasher_t.get_hash.
196 */
197 static void get_hash(private_sha1_hasher_t *this, chunk_t chunk, u_int8_t *buffer)
198 {
199 SHA1Update(this, chunk.ptr, chunk.len);
200 if (buffer != NULL)
201 {
202 SHA1Final(this, buffer);
203 reset(this);
204 }
205 }
206
207 /**
208 * Implementation of hasher_t.allocate_hash.
209 */
210 static void allocate_hash(private_sha1_hasher_t *this, chunk_t chunk, chunk_t *hash)
211 {
212 SHA1Update(this, chunk.ptr, chunk.len);
213 if (hash != NULL)
214 {
215 hash->ptr = malloc(HASH_SIZE_SHA1);
216 hash->len = HASH_SIZE_SHA1;
217
218 SHA1Final(this, hash->ptr);
219 reset(this);
220 }
221 }
222
223 /**
224 * Implementation of hasher_t.get_hash_size.
225 */
226 static size_t get_hash_size(private_sha1_hasher_t *this)
227 {
228 return HASH_SIZE_SHA1;
229 }
230
231 /**
232 * Implementation of hasher_t.destroy.
233 */
234 static void destroy(private_sha1_hasher_t *this)
235 {
236 free(this);
237 }
238
239 /*
240 * Described in header.
241 */
242 sha1_hasher_t *sha1_hasher_create(hash_algorithm_t algo)
243 {
244 private_sha1_hasher_t *this;
245 if (algo != HASH_SHA1)
246 {
247 return NULL;
248 }
249 this = malloc_thing(private_sha1_hasher_t);
250 this->public.hasher_interface.get_hash = (void (*) (hasher_t*, chunk_t, u_int8_t*))get_hash;
251 this->public.hasher_interface.allocate_hash = (void (*) (hasher_t*, chunk_t, chunk_t*))allocate_hash;
252 this->public.hasher_interface.get_hash_size = (size_t (*) (hasher_t*))get_hash_size;
253 this->public.hasher_interface.reset = (void (*) (hasher_t*))reset;
254 this->public.hasher_interface.destroy = (void (*) (hasher_t*))destroy;
255
256 /* initialize */
257 reset(this);
258
259 return &(this->public);
260 }
261