1 /*
2  *  FIPS-180-2 compliant SHA-256 implementation
3  *
4  *  Copyright (C) 2003-2006  Christophe Devine
5  *
6  *  This library is free software; you can redistribute it and/or
7  *  modify it under the terms of the GNU Lesser General Public
8  *  License, version 2.1 as published by the Free Software Foundation.
9  *
10  *  This library is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  *  Lesser General Public License for more details.
14  *
15  *  You should have received a copy of the GNU Lesser General Public
16  *  License along with this library; if not, write to the Free Software
17  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
18  *  MA  02110-1301  USA
19  */
20 /*
21  *  The SHA-256 standard was published by NIST in 2002.
22  *
23  *  http://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf
24  */
25 
26 #ifndef _CRT_SECURE_NO_DEPRECATE
27 #define _CRT_SECURE_NO_DEPRECATE 1
28 #endif
29 
30 #include <string.h>
31 #include <stdio.h>
32 
33 #include "sha2.h"
34 #include "filesys.h"
35 #include "../shared/shared.h"
36 
37 /**
38  * 32-bit integer manipulation macros (big endian)
39  */
40 #ifndef GET_UINT32_BE
41 #define GET_UINT32_BE(n,b,i)                    \
42 {                                               \
43     (n) = ( (uint64_t) (b)[(i)    ] << 24 )        \
44         | ( (uint64_t) (b)[(i) + 1] << 16 )        \
45         | ( (uint64_t) (b)[(i) + 2] <<  8 )        \
46         | ( (uint64_t) (b)[(i) + 3]       );       \
47 }
48 #endif
49 #ifndef PUT_UINT32_BE
50 #define PUT_UINT32_BE(n,b,i)                    \
51 {                                               \
52     (b)[(i)    ] = (byte) ( (n) >> 24 );       \
53     (b)[(i) + 1] = (byte) ( (n) >> 16 );       \
54     (b)[(i) + 2] = (byte) ( (n) >>  8 );       \
55     (b)[(i) + 3] = (byte) ( (n)       );       \
56 }
57 #endif
58 
59 /*
60  * Core SHA-256 functions
61  */
Com_SHA2Starts(sha2_context * ctx)62 void Com_SHA2Starts (sha2_context *ctx)
63 {
64 	ctx->total[0] = 0;
65 	ctx->total[1] = 0;
66 
67 	ctx->state[0] = 0x6A09E667;
68 	ctx->state[1] = 0xBB67AE85;
69 	ctx->state[2] = 0x3C6EF372;
70 	ctx->state[3] = 0xA54FF53A;
71 	ctx->state[4] = 0x510E527F;
72 	ctx->state[5] = 0x9B05688C;
73 	ctx->state[6] = 0x1F83D9AB;
74 	ctx->state[7] = 0x5BE0CD19;
75 }
76 
Com_SHA2Process(sha2_context * ctx,const byte data[64])77 static void Com_SHA2Process (sha2_context *ctx, const byte data[64])
78 {
79 	uint64_t temp1, temp2, W[64];
80 	uint64_t A, B, C, D, E, F, G, H;
81 
82 	GET_UINT32_BE(W[0], data, 0);
83 	GET_UINT32_BE(W[1], data, 4);
84 	GET_UINT32_BE(W[2], data, 8);
85 	GET_UINT32_BE(W[3], data, 12);
86 	GET_UINT32_BE(W[4], data, 16);
87 	GET_UINT32_BE(W[5], data, 20);
88 	GET_UINT32_BE(W[6], data, 24);
89 	GET_UINT32_BE(W[7], data, 28);
90 	GET_UINT32_BE(W[8], data, 32);
91 	GET_UINT32_BE(W[9], data, 36);
92 	GET_UINT32_BE(W[10], data, 40);
93 	GET_UINT32_BE(W[11], data, 44);
94 	GET_UINT32_BE(W[12], data, 48);
95 	GET_UINT32_BE(W[13], data, 52);
96 	GET_UINT32_BE(W[14], data, 56);
97 	GET_UINT32_BE(W[15], data, 60);
98 
99 #define  SHR(x,n) ((x & 0xFFFFFFFF) >> n)
100 #define ROTR(x,n) (SHR(x,n) | (x << (32 - n)))
101 
102 #define S0(x) (ROTR(x, 7) ^ ROTR(x,18) ^  SHR(x, 3))
103 #define S1(x) (ROTR(x,17) ^ ROTR(x,19) ^  SHR(x,10))
104 
105 #define S2(x) (ROTR(x, 2) ^ ROTR(x,13) ^ ROTR(x,22))
106 #define S3(x) (ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x,25))
107 
108 #define F0(x,y,z) ((x & y) | (z & (x | y)))
109 #define F1(x,y,z) (z ^ (x & (y ^ z)))
110 
111 #define R(t)                                    \
112 (                                               \
113     W[t] = S1(W[t -  2]) + W[t -  7] +          \
114            S0(W[t - 15]) + W[t - 16]            \
115 )
116 
117 #define P(a,b,c,d,e,f,g,h,x,K)                  \
118 {                                               \
119     temp1 = h + S3(e) + F1(e,f,g) + K + x;      \
120     temp2 = S2(a) + F0(a,b,c);                  \
121     d += temp1; h = temp1 + temp2;              \
122 }
123 
124 	A = ctx->state[0];
125 	B = ctx->state[1];
126 	C = ctx->state[2];
127 	D = ctx->state[3];
128 	E = ctx->state[4];
129 	F = ctx->state[5];
130 	G = ctx->state[6];
131 	H = ctx->state[7];
132 
133 	P(A, B, C, D, E, F, G, H, W[0], 0x428A2F98);
134 	P(H, A, B, C, D, E, F, G, W[1], 0x71374491);
135 	P(G, H, A, B, C, D, E, F, W[2], 0xB5C0FBCF);
136 	P(F, G, H, A, B, C, D, E, W[3], 0xE9B5DBA5);
137 	P(E, F, G, H, A, B, C, D, W[4], 0x3956C25B);
138 	P(D, E, F, G, H, A, B, C, W[5], 0x59F111F1);
139 	P(C, D, E, F, G, H, A, B, W[6], 0x923F82A4);
140 	P(B, C, D, E, F, G, H, A, W[7], 0xAB1C5ED5);
141 	P(A, B, C, D, E, F, G, H, W[8], 0xD807AA98);
142 	P(H, A, B, C, D, E, F, G, W[9], 0x12835B01);
143 	P(G, H, A, B, C, D, E, F, W[10], 0x243185BE);
144 	P(F, G, H, A, B, C, D, E, W[11], 0x550C7DC3);
145 	P(E, F, G, H, A, B, C, D, W[12], 0x72BE5D74);
146 	P(D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE);
147 	P(C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7);
148 	P(B, C, D, E, F, G, H, A, W[15], 0xC19BF174);
149 	P(A, B, C, D, E, F, G, H, R(16), 0xE49B69C1);
150 	P(H, A, B, C, D, E, F, G, R(17), 0xEFBE4786);
151 	P(G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6);
152 	P(F, G, H, A, B, C, D, E, R(19), 0x240CA1CC);
153 	P(E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F);
154 	P(D, E, F, G, H, A, B, C, R(21), 0x4A7484AA);
155 	P(C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC);
156 	P(B, C, D, E, F, G, H, A, R(23), 0x76F988DA);
157 	P(A, B, C, D, E, F, G, H, R(24), 0x983E5152);
158 	P(H, A, B, C, D, E, F, G, R(25), 0xA831C66D);
159 	P(G, H, A, B, C, D, E, F, R(26), 0xB00327C8);
160 	P(F, G, H, A, B, C, D, E, R(27), 0xBF597FC7);
161 	P(E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3);
162 	P(D, E, F, G, H, A, B, C, R(29), 0xD5A79147);
163 	P(C, D, E, F, G, H, A, B, R(30), 0x06CA6351);
164 	P(B, C, D, E, F, G, H, A, R(31), 0x14292967);
165 	P(A, B, C, D, E, F, G, H, R(32), 0x27B70A85);
166 	P(H, A, B, C, D, E, F, G, R(33), 0x2E1B2138);
167 	P(G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC);
168 	P(F, G, H, A, B, C, D, E, R(35), 0x53380D13);
169 	P(E, F, G, H, A, B, C, D, R(36), 0x650A7354);
170 	P(D, E, F, G, H, A, B, C, R(37), 0x766A0ABB);
171 	P(C, D, E, F, G, H, A, B, R(38), 0x81C2C92E);
172 	P(B, C, D, E, F, G, H, A, R(39), 0x92722C85);
173 	P(A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1);
174 	P(H, A, B, C, D, E, F, G, R(41), 0xA81A664B);
175 	P(G, H, A, B, C, D, E, F, R(42), 0xC24B8B70);
176 	P(F, G, H, A, B, C, D, E, R(43), 0xC76C51A3);
177 	P(E, F, G, H, A, B, C, D, R(44), 0xD192E819);
178 	P(D, E, F, G, H, A, B, C, R(45), 0xD6990624);
179 	P(C, D, E, F, G, H, A, B, R(46), 0xF40E3585);
180 	P(B, C, D, E, F, G, H, A, R(47), 0x106AA070);
181 	P(A, B, C, D, E, F, G, H, R(48), 0x19A4C116);
182 	P(H, A, B, C, D, E, F, G, R(49), 0x1E376C08);
183 	P(G, H, A, B, C, D, E, F, R(50), 0x2748774C);
184 	P(F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5);
185 	P(E, F, G, H, A, B, C, D, R(52), 0x391C0CB3);
186 	P(D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A);
187 	P(C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F);
188 	P(B, C, D, E, F, G, H, A, R(55), 0x682E6FF3);
189 	P(A, B, C, D, E, F, G, H, R(56), 0x748F82EE);
190 	P(H, A, B, C, D, E, F, G, R(57), 0x78A5636F);
191 	P(G, H, A, B, C, D, E, F, R(58), 0x84C87814);
192 	P(F, G, H, A, B, C, D, E, R(59), 0x8CC70208);
193 	P(E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA);
194 	P(D, E, F, G, H, A, B, C, R(61), 0xA4506CEB);
195 	P(C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7);
196 	P(B, C, D, E, F, G, H, A, R(63), 0xC67178F2);
197 
198 	ctx->state[0] += A;
199 	ctx->state[1] += B;
200 	ctx->state[2] += C;
201 	ctx->state[3] += D;
202 	ctx->state[4] += E;
203 	ctx->state[5] += F;
204 	ctx->state[6] += G;
205 	ctx->state[7] += H;
206 }
207 
Com_SHA2Update(sha2_context * ctx,const byte * input,uint32_t length)208 void Com_SHA2Update (sha2_context *ctx, const byte* input, uint32_t length)
209 {
210 	if (!length)
211 		return;
212 
213 	uint64_t left = ctx->total[0] & 0x3F;
214 	const uint64_t fill = 64 - left;
215 
216 	ctx->total[0] += length;
217 	ctx->total[0] &= 0xFFFFFFFF;
218 
219 	if (ctx->total[0] < length)
220 		ctx->total[1]++;
221 
222 	if (left && length >= fill) {
223 		memcpy((void*) (ctx->buffer + left), (const void*) input, fill);
224 		Com_SHA2Process(ctx, ctx->buffer);
225 		length -= fill;
226 		input += fill;
227 		left = 0;
228 	}
229 
230 	while (length >= 64) {
231 		Com_SHA2Process(ctx, input);
232 		length -= 64;
233 		input += 64;
234 	}
235 
236 	if (length) {
237 		memcpy((void*) (ctx->buffer + left), (const void*) input, length);
238 	}
239 }
240 
241 static const byte sha2_padding[64] =
242 		{ 0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
243 				0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
244 
Com_SHA2Finish(sha2_context * ctx,byte digest[32])245 void Com_SHA2Finish (sha2_context *ctx, byte digest[32])
246 {
247 	byte msglen[8];
248 
249 	const uint64_t high = (ctx->total[0] >> 29) | (ctx->total[1] << 3);
250 	const uint64_t low = (ctx->total[0] << 3);
251 
252 	PUT_UINT32_BE(high, msglen, 0);
253 	PUT_UINT32_BE(low, msglen, 4);
254 
255 	const uint64_t last = ctx->total[0] & 0x3F;
256 	const uint64_t padn = (last < 56) ? (56 - last) : (120 - last);
257 
258 	Com_SHA2Update(ctx, sha2_padding, padn);
259 	Com_SHA2Update(ctx, msglen, 8);
260 
261 	PUT_UINT32_BE(ctx->state[0], digest, 0);
262 	PUT_UINT32_BE(ctx->state[1], digest, 4);
263 	PUT_UINT32_BE(ctx->state[2], digest, 8);
264 	PUT_UINT32_BE(ctx->state[3], digest, 12);
265 	PUT_UINT32_BE(ctx->state[4], digest, 16);
266 	PUT_UINT32_BE(ctx->state[5], digest, 20);
267 	PUT_UINT32_BE(ctx->state[6], digest, 24);
268 	PUT_UINT32_BE(ctx->state[7], digest, 28);
269 }
270 
Com_SHA2File(const char * filename,byte digest[32])271 bool Com_SHA2File (const char* filename, byte digest[32])
272 {
273 	ScopedFile f;
274 	const int filelen = FS_OpenFile(filename, &f, FILE_READ);
275 	if (filelen < 1)
276 		return false;
277 
278 	sha2_context ctx;
279 	Com_SHA2Starts(&ctx);
280 
281 	byte buf[1024];
282 	for (;;) {
283 		const int n = FS_Read(buf, sizeof(buf), &f);
284 		if (n < 1)
285 			break;
286 		Com_SHA2Update(&ctx, buf, (uint32_t) n);
287 	}
288 
289 	Com_SHA2Finish(&ctx, digest);
290 	return true;
291 }
292 
Com_SHA2Csum(const byte * buf,uint32_t buflen,byte digest[32])293 void Com_SHA2Csum (const byte* buf, uint32_t buflen, byte digest[32])
294 {
295 	sha2_context ctx;
296 
297 	Com_SHA2Starts(&ctx);
298 	Com_SHA2Update(&ctx, buf, buflen);
299 	Com_SHA2Finish(&ctx, digest);
300 }
301 
Com_SHA2ToHex(const byte digest[32],char final[65])302 void Com_SHA2ToHex (const byte digest[32], char final[65])
303 {
304 	final[0] = '\0';
305 	for (int i = 0; i < 32; i++)
306 		Q_strcat(final, 65, "%02x", digest[i]);
307 }
308 
Com_SHA2Hmac(const byte * buf,uint32_t buflen,const byte * key,uint32_t keylen,byte digest[32])309 void Com_SHA2Hmac (const byte* buf, uint32_t buflen, const byte* key, uint32_t keylen, byte digest[32])
310 {
311 	uint32_t i;
312 	sha2_context ctx;
313 	byte k_ipad[64];
314 	byte k_opad[64];
315 	byte tmpbuf[32];
316 
317 	memset(k_ipad, 0x36, 64);
318 	memset(k_opad, 0x5C, 64);
319 
320 	for (i = 0; i < keylen; i++) {
321 		if (i >= 64)
322 			break;
323 
324 		k_ipad[i] ^= key[i];
325 		k_opad[i] ^= key[i];
326 	}
327 
328 	Com_SHA2Starts(&ctx);
329 	Com_SHA2Update(&ctx, k_ipad, 64);
330 	Com_SHA2Update(&ctx, buf, buflen);
331 	Com_SHA2Finish(&ctx, tmpbuf);
332 
333 	Com_SHA2Starts(&ctx);
334 	Com_SHA2Update(&ctx, k_opad, 64);
335 	Com_SHA2Update(&ctx, tmpbuf, 32);
336 	Com_SHA2Finish(&ctx, digest);
337 
338 	memset(k_ipad, 0, 64);
339 	memset(k_opad, 0, 64);
340 	memset(tmpbuf, 0, 32);
341 	memset(&ctx, 0, sizeof(sha2_context));
342 }
343