1 /*
2 * SHA-1 in C
3 * By Steve Reid <sreid@sea-to-sky.net>
4 * 100% Public Domain
5 *
6 * -----------------
7 * Modified 7/98
8 * By James H. Brown <jbrown@burgoyne.com>
9 * Still 100% Public Domain
10 *
11 * Corrected a problem which generated improper hash values on 16 bit machines
12 * Routine SHA1Update changed from
13 * void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned int
14 * len)
15 * to
16 * void SHA1Update(SHA1_CTX* context, unsigned char* data, unsigned
17 * long len)
18 *
19 * The 'len' parameter was declared an int which works fine on 32 bit machines.
20 * However, on 16 bit machines an int is too small for the shifts being done
21 * against
22 * it. This caused the hash function to generate incorrect values if len was
23 * greater than 8191 (8K - 1) due to the 'len << 3' on line 3 of SHA1Update().
24 *
25 * Since the file IO in main() reads 16K at a time, any file 8K or larger would
26 * be guaranteed to generate the wrong hash (e.g. Test Vector #3, a million
27 * "a"s).
28 *
29 * I also changed the declaration of variables i & j in SHA1Update to
30 * unsigned long from unsigned int for the same reason.
31 *
32 * These changes should make no difference to any 32 bit implementations since
33 * an
34 * int and a long are the same size in those environments.
35 *
36 * --
37 * I also corrected a few compiler warnings generated by Borland C.
38 * 1. Added #include <process.h> for exit() prototype
39 * 2. Removed unused variable 'j' in SHA1Final
40 * 3. Changed exit(0) to return(0) at end of main.
41 *
42 * ALL changes I made can be located by searching for comments containing 'JHB'
43 * -----------------
44 * Modified 8/98
45 * By Steve Reid <sreid@sea-to-sky.net>
46 * Still 100% public domain
47 *
48 * 1- Removed #include <process.h> and used return() instead of exit()
49 * 2- Fixed overwriting of finalcount in SHA1Final() (discovered by Chris Hall)
50 * 3- Changed email address from steve@edmweb.com to sreid@sea-to-sky.net
51 *
52 * -----------------
53 * Modified 4/01
54 * By Saul Kravitz <Saul.Kravitz@celera.com>
55 * Still 100% PD
56 * Modified to run on Compaq Alpha hardware.
57 *
58 * -----------------
59 * Modified 07/2002
60 * By Ralph Giles <giles@ghostscript.com>
61 * Still 100% public domain
62 * modified for use with stdint types, autoconf
63 * code cleanup, removed attribution comments
64 * switched SHA1Final() argument order for consistency
65 * use SHA1_ prefix for public api
66 * move public api to sha1.h
67 *
68 * -----------------
69 * Modified 02/2012
70 * By Justin Uberti <juberti@google.com>
71 * Remove underscore from SHA1 prefix to avoid conflict with OpenSSL
72 * Remove test code
73 * Untabify
74 *
75 * -----------------
76 * Modified 03/2012
77 * By Ronghua Wu <ronghuawu@google.com>
78 * Change the typedef of uint32(8)_t to uint32(8). We need this because in the
79 * chromium android build, the stdio.h will include stdint.h which already
80 * defined uint32(8)_t.
81 *
82 * -----------------
83 * Modified 04/2012
84 * By Frank Barchard <fbarchard@google.com>
85 * Ported to C++, Google style, change len to size_t, enable SHA1HANDSOFF
86 *
87 * Test Vectors (from FIPS PUB 180-1)
88 * "abc"
89 * A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D
90 * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
91 * 84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1
92 * A million repetitions of "a"
93 * 34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F
94 */
95
96 // Enabling SHA1HANDSOFF preserves the caller's data buffer.
97 // Disabling SHA1HANDSOFF the buffer will be modified (end swapped).
98 #define SHA1HANDSOFF
99
100 #include "webrtc/base/sha1.h"
101
102 #include <stdio.h>
103 #include <string.h>
104
105 namespace rtc {
106
107 void SHA1Transform(uint32 state[5], const uint8 buffer[64]);
108
109 #define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))
110
111 // blk0() and blk() perform the initial expand.
112 // I got the idea of expanding during the round function from SSLeay
113 // FIXME: can we do this in an endian-proof way?
114 #ifdef ARCH_CPU_BIG_ENDIAN
115 #define blk0(i) block->l[i]
116 #else
117 #define blk0(i) (block->l[i] = (rol(block->l[i], 24) & 0xFF00FF00) | \
118 (rol(block->l[i], 8) & 0x00FF00FF))
119 #endif
120 #define blk(i) (block->l[i & 15] = rol(block->l[(i + 13) & 15] ^ \
121 block->l[(i + 8) & 15] ^ block->l[(i + 2) & 15] ^ block->l[i & 15], 1))
122
123 // (R0+R1), R2, R3, R4 are the different operations used in SHA1.
124 #define R0(v, w, x, y, z, i) \
125 z += ((w & (x ^ y)) ^ y) + blk0(i) + 0x5A827999 + rol(v, 5); \
126 w = rol(w, 30);
127 #define R1(v, w, x, y, z, i) \
128 z += ((w & (x ^ y)) ^ y) + blk(i) + 0x5A827999 + rol(v, 5); \
129 w = rol(w, 30);
130 #define R2(v, w, x, y, z, i) \
131 z += (w ^ x ^ y) + blk(i) + 0x6ED9EBA1 + rol(v, 5);\
132 w = rol(w, 30);
133 #define R3(v, w, x, y, z, i) \
134 z += (((w | x) & y) | (w & x)) + blk(i) + 0x8F1BBCDC + rol(v, 5); \
135 w = rol(w, 30);
136 #define R4(v, w, x, y, z, i) \
137 z += (w ^ x ^ y) + blk(i) + 0xCA62C1D6 + rol(v, 5); \
138 w = rol(w, 30);
139
140 #ifdef VERBOSE // SAK
SHAPrintContext(SHA1_CTX * context,char * msg)141 void SHAPrintContext(SHA1_CTX *context, char *msg) {
142 printf("%s (%d,%d) %x %x %x %x %x\n",
143 msg,
144 context->count[0], context->count[1],
145 context->state[0],
146 context->state[1],
147 context->state[2],
148 context->state[3],
149 context->state[4]);
150 }
151 #endif /* VERBOSE */
152
153 // Hash a single 512-bit block. This is the core of the algorithm.
SHA1Transform(uint32 state[5],const uint8 buffer[64])154 void SHA1Transform(uint32 state[5], const uint8 buffer[64]) {
155 union CHAR64LONG16 {
156 uint8 c[64];
157 uint32 l[16];
158 };
159 #ifdef SHA1HANDSOFF
160 static uint8 workspace[64];
161 memcpy(workspace, buffer, 64);
162 CHAR64LONG16* block = reinterpret_cast<CHAR64LONG16*>(workspace);
163 #else
164 // Note(fbarchard): This option does modify the user's data buffer.
165 CHAR64LONG16* block = const_cast<CHAR64LONG16*>(
166 reinterpret_cast<const CHAR64LONG16*>(buffer));
167 #endif
168
169 // Copy context->state[] to working vars.
170 uint32 a = state[0];
171 uint32 b = state[1];
172 uint32 c = state[2];
173 uint32 d = state[3];
174 uint32 e = state[4];
175
176 // 4 rounds of 20 operations each. Loop unrolled.
177 // Note(fbarchard): The following has lint warnings for multiple ; on
178 // a line and no space after , but is left as-is to be similar to the
179 // original code.
180 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);
181 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);
182 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);
183 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);
184 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);
185 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);
186 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);
187 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);
188 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);
189 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);
190 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);
191 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);
192 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);
193 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);
194 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);
195 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);
196 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);
197 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);
198 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);
199 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);
200
201 // Add the working vars back into context.state[].
202 state[0] += a;
203 state[1] += b;
204 state[2] += c;
205 state[3] += d;
206 state[4] += e;
207 }
208
209 // SHA1Init - Initialize new context.
SHA1Init(SHA1_CTX * context)210 void SHA1Init(SHA1_CTX* context) {
211 // SHA1 initialization constants.
212 context->state[0] = 0x67452301;
213 context->state[1] = 0xEFCDAB89;
214 context->state[2] = 0x98BADCFE;
215 context->state[3] = 0x10325476;
216 context->state[4] = 0xC3D2E1F0;
217 context->count[0] = context->count[1] = 0;
218 }
219
220 // Run your data through this.
SHA1Update(SHA1_CTX * context,const uint8 * data,size_t input_len)221 void SHA1Update(SHA1_CTX* context, const uint8* data, size_t input_len) {
222 size_t i = 0;
223
224 #ifdef VERBOSE
225 SHAPrintContext(context, "before");
226 #endif
227
228 // Compute number of bytes mod 64.
229 size_t index = (context->count[0] >> 3) & 63;
230
231 // Update number of bits.
232 // TODO: Use uint64 instead of 2 uint32 for count.
233 // count[0] has low 29 bits for byte count + 3 pad 0's making 32 bits for
234 // bit count.
235 // Add bit count to low uint32
236 context->count[0] += static_cast<uint32>(input_len << 3);
237 if (context->count[0] < static_cast<uint32>(input_len << 3)) {
238 ++context->count[1]; // if overlow (carry), add one to high word
239 }
240 context->count[1] += static_cast<uint32>(input_len >> 29);
241 if ((index + input_len) > 63) {
242 i = 64 - index;
243 memcpy(&context->buffer[index], data, i);
244 SHA1Transform(context->state, context->buffer);
245 for (; i + 63 < input_len; i += 64) {
246 SHA1Transform(context->state, data + i);
247 }
248 index = 0;
249 }
250 memcpy(&context->buffer[index], &data[i], input_len - i);
251
252 #ifdef VERBOSE
253 SHAPrintContext(context, "after ");
254 #endif
255 }
256
257 // Add padding and return the message digest.
SHA1Final(SHA1_CTX * context,uint8 digest[SHA1_DIGEST_SIZE])258 void SHA1Final(SHA1_CTX* context, uint8 digest[SHA1_DIGEST_SIZE]) {
259 uint8 finalcount[8];
260 for (int i = 0; i < 8; ++i) {
261 // Endian independent
262 finalcount[i] = static_cast<uint8>(
263 (context->count[(i >= 4 ? 0 : 1)] >> ((3 - (i & 3)) * 8) ) & 255);
264 }
265 SHA1Update(context, reinterpret_cast<const uint8*>("\200"), 1);
266 while ((context->count[0] & 504) != 448) {
267 SHA1Update(context, reinterpret_cast<const uint8*>("\0"), 1);
268 }
269 SHA1Update(context, finalcount, 8); // Should cause a SHA1Transform().
270 for (int i = 0; i < SHA1_DIGEST_SIZE; ++i) {
271 digest[i] = static_cast<uint8>(
272 (context->state[i >> 2] >> ((3 - (i & 3)) * 8) ) & 255);
273 }
274
275 // Wipe variables.
276 memset(context->buffer, 0, 64);
277 memset(context->state, 0, 20);
278 memset(context->count, 0, 8);
279 memset(finalcount, 0, 8); // SWR
280
281 #ifdef SHA1HANDSOFF // Make SHA1Transform overwrite its own static vars.
282 SHA1Transform(context->state, context->buffer);
283 #endif
284 }
285
286 } // namespace rtc
287