xref: /openbsd-src/gnu/usr.bin/perl/cpan/Digest-SHA/src/sha.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*
2  * sha.c: routines to compute SHA-1/224/256/384/512 digests
3  *
4  * Ref: NIST FIPS PUB 180-2 Secure Hash Standard
5  *
6  * Copyright (C) 2003-2013 Mark Shelor, All Rights Reserved
7  *
8  * Version: 5.84
9  * Sat Mar  9 17:36:08 MST 2013
10  *
11  */
12 
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <stddef.h>
16 #include <string.h>
17 #include <ctype.h>
18 #include "sha.h"
19 #include "sha64bit.h"
20 
21 #define W32	SHA32			/* useful abbreviations */
22 #define C32	SHA32_CONST
23 #define SR32	SHA32_SHR
24 #define SL32	SHA32_SHL
25 #define LO32	SHA_LO32
26 #define UCHR	unsigned char
27 #define UINT	unsigned int
28 #define ULNG	unsigned long
29 #define VP	void *
30 
31 #define ROTR(x, n)	(SR32(x, n) | SL32(x, 32-(n)))
32 #define ROTL(x, n)	(SL32(x, n) | SR32(x, 32-(n)))
33 
34 #define Ch(x, y, z)	((z) ^ ((x) & ((y) ^ (z))))
35 #define Pa(x, y, z)	((x) ^ (y) ^ (z))
36 #define Ma(x, y, z)	(((x) & (y)) | ((z) & ((x) | (y))))
37 
38 #define SIGMA0(x)	(ROTR(x,  2) ^ ROTR(x, 13) ^ ROTR(x, 22))
39 #define SIGMA1(x)	(ROTR(x,  6) ^ ROTR(x, 11) ^ ROTR(x, 25))
40 #define sigma0(x)	(ROTR(x,  7) ^ ROTR(x, 18) ^ SR32(x,  3))
41 #define sigma1(x)	(ROTR(x, 17) ^ ROTR(x, 19) ^ SR32(x, 10))
42 
43 #define K1	C32(0x5a827999)		/* SHA-1 constants */
44 #define K2	C32(0x6ed9eba1)
45 #define K3	C32(0x8f1bbcdc)
46 #define K4	C32(0xca62c1d6)
47 
48 static W32 K256[64] =			/* SHA-224/256 constants */
49 {
50 	C32(0x428a2f98), C32(0x71374491), C32(0xb5c0fbcf), C32(0xe9b5dba5),
51 	C32(0x3956c25b), C32(0x59f111f1), C32(0x923f82a4), C32(0xab1c5ed5),
52 	C32(0xd807aa98), C32(0x12835b01), C32(0x243185be), C32(0x550c7dc3),
53 	C32(0x72be5d74), C32(0x80deb1fe), C32(0x9bdc06a7), C32(0xc19bf174),
54 	C32(0xe49b69c1), C32(0xefbe4786), C32(0x0fc19dc6), C32(0x240ca1cc),
55 	C32(0x2de92c6f), C32(0x4a7484aa), C32(0x5cb0a9dc), C32(0x76f988da),
56 	C32(0x983e5152), C32(0xa831c66d), C32(0xb00327c8), C32(0xbf597fc7),
57 	C32(0xc6e00bf3), C32(0xd5a79147), C32(0x06ca6351), C32(0x14292967),
58 	C32(0x27b70a85), C32(0x2e1b2138), C32(0x4d2c6dfc), C32(0x53380d13),
59 	C32(0x650a7354), C32(0x766a0abb), C32(0x81c2c92e), C32(0x92722c85),
60 	C32(0xa2bfe8a1), C32(0xa81a664b), C32(0xc24b8b70), C32(0xc76c51a3),
61 	C32(0xd192e819), C32(0xd6990624), C32(0xf40e3585), C32(0x106aa070),
62 	C32(0x19a4c116), C32(0x1e376c08), C32(0x2748774c), C32(0x34b0bcb5),
63 	C32(0x391c0cb3), C32(0x4ed8aa4a), C32(0x5b9cca4f), C32(0x682e6ff3),
64 	C32(0x748f82ee), C32(0x78a5636f), C32(0x84c87814), C32(0x8cc70208),
65 	C32(0x90befffa), C32(0xa4506ceb), C32(0xbef9a3f7), C32(0xc67178f2)
66 };
67 
68 static W32 H01[5] =			/* SHA-1 initial hash value */
69 {
70 	C32(0x67452301), C32(0xefcdab89), C32(0x98badcfe),
71 	C32(0x10325476), C32(0xc3d2e1f0)
72 };
73 
74 static W32 H0224[8] =			/* SHA-224 initial hash value */
75 {
76 	C32(0xc1059ed8), C32(0x367cd507), C32(0x3070dd17), C32(0xf70e5939),
77 	C32(0xffc00b31), C32(0x68581511), C32(0x64f98fa7), C32(0xbefa4fa4)
78 };
79 
80 static W32 H0256[8] =			/* SHA-256 initial hash value */
81 {
82 	C32(0x6a09e667), C32(0xbb67ae85), C32(0x3c6ef372), C32(0xa54ff53a),
83 	C32(0x510e527f), C32(0x9b05688c), C32(0x1f83d9ab), C32(0x5be0cd19)
84 };
85 
86 static void sha1(SHA *s, UCHR *block)		/* SHA-1 transform */
87 {
88 	W32 a, b, c, d, e;
89 	W32 W[16];
90 	W32 *wp = W;
91 	W32 *H = (W32 *) s->H;
92 
93 	SHA32_SCHED(W, block);
94 
95 /*
96  * Use SHA-1 alternate method from FIPS PUB 180-2 (ref. 6.1.3)
97  *
98  * To improve performance, unroll the loop and consolidate assignments
99  * by changing the roles of variables "a" through "e" at each step.
100  * Note that the variable "T" is no longer needed.
101  */
102 
103 #define M1(a, b, c, d, e, f, k, w)		\
104 	e += ROTL(a, 5) + f(b, c, d) + k + w;	\
105 	b =  ROTL(b, 30)
106 
107 #define M11(f, k, w)	M1(a, b, c, d, e, f, k, w);
108 #define M12(f, k, w)	M1(e, a, b, c, d, f, k, w);
109 #define M13(f, k, w)	M1(d, e, a, b, c, f, k, w);
110 #define M14(f, k, w)	M1(c, d, e, a, b, f, k, w);
111 #define M15(f, k, w)	M1(b, c, d, e, a, f, k, w);
112 
113 #define W11(s)	W[(s+ 0) & 0xf]
114 #define W12(s)	W[(s+13) & 0xf]
115 #define W13(s)	W[(s+ 8) & 0xf]
116 #define W14(s)	W[(s+ 2) & 0xf]
117 
118 #define A1(s)	(W11(s) = ROTL(W11(s) ^ W12(s) ^ W13(s) ^ W14(s), 1))
119 
120 	a = H[0]; b = H[1]; c = H[2]; d = H[3]; e = H[4];
121 
122 	M11(Ch, K1,  *wp++); M12(Ch, K1,  *wp++); M13(Ch, K1,  *wp++);
123 	M14(Ch, K1,  *wp++); M15(Ch, K1,  *wp++); M11(Ch, K1,  *wp++);
124 	M12(Ch, K1,  *wp++); M13(Ch, K1,  *wp++); M14(Ch, K1,  *wp++);
125 	M15(Ch, K1,  *wp++); M11(Ch, K1,  *wp++); M12(Ch, K1,  *wp++);
126 	M13(Ch, K1,  *wp++); M14(Ch, K1,  *wp++); M15(Ch, K1,  *wp++);
127 	M11(Ch, K1,  *wp  ); M12(Ch, K1, A1( 0)); M13(Ch, K1, A1( 1));
128 	M14(Ch, K1, A1( 2)); M15(Ch, K1, A1( 3)); M11(Pa, K2, A1( 4));
129 	M12(Pa, K2, A1( 5)); M13(Pa, K2, A1( 6)); M14(Pa, K2, A1( 7));
130 	M15(Pa, K2, A1( 8)); M11(Pa, K2, A1( 9)); M12(Pa, K2, A1(10));
131 	M13(Pa, K2, A1(11)); M14(Pa, K2, A1(12)); M15(Pa, K2, A1(13));
132 	M11(Pa, K2, A1(14)); M12(Pa, K2, A1(15)); M13(Pa, K2, A1( 0));
133 	M14(Pa, K2, A1( 1)); M15(Pa, K2, A1( 2)); M11(Pa, K2, A1( 3));
134 	M12(Pa, K2, A1( 4)); M13(Pa, K2, A1( 5)); M14(Pa, K2, A1( 6));
135 	M15(Pa, K2, A1( 7)); M11(Ma, K3, A1( 8)); M12(Ma, K3, A1( 9));
136 	M13(Ma, K3, A1(10)); M14(Ma, K3, A1(11)); M15(Ma, K3, A1(12));
137 	M11(Ma, K3, A1(13)); M12(Ma, K3, A1(14)); M13(Ma, K3, A1(15));
138 	M14(Ma, K3, A1( 0)); M15(Ma, K3, A1( 1)); M11(Ma, K3, A1( 2));
139 	M12(Ma, K3, A1( 3)); M13(Ma, K3, A1( 4)); M14(Ma, K3, A1( 5));
140 	M15(Ma, K3, A1( 6)); M11(Ma, K3, A1( 7)); M12(Ma, K3, A1( 8));
141 	M13(Ma, K3, A1( 9)); M14(Ma, K3, A1(10)); M15(Ma, K3, A1(11));
142 	M11(Pa, K4, A1(12)); M12(Pa, K4, A1(13)); M13(Pa, K4, A1(14));
143 	M14(Pa, K4, A1(15)); M15(Pa, K4, A1( 0)); M11(Pa, K4, A1( 1));
144 	M12(Pa, K4, A1( 2)); M13(Pa, K4, A1( 3)); M14(Pa, K4, A1( 4));
145 	M15(Pa, K4, A1( 5)); M11(Pa, K4, A1( 6)); M12(Pa, K4, A1( 7));
146 	M13(Pa, K4, A1( 8)); M14(Pa, K4, A1( 9)); M15(Pa, K4, A1(10));
147 	M11(Pa, K4, A1(11)); M12(Pa, K4, A1(12)); M13(Pa, K4, A1(13));
148 	M14(Pa, K4, A1(14)); M15(Pa, K4, A1(15));
149 
150 	H[0] += a; H[1] += b; H[2] += c; H[3] += d; H[4] += e;
151 }
152 
153 static void sha256(SHA *s, UCHR *block)		/* SHA-224/256 transform */
154 {
155 	W32 a, b, c, d, e, f, g, h, T1;
156 	W32 W[16];
157 	W32 *kp = K256;
158 	W32 *wp = W;
159 	W32 *H = (W32 *) s->H;
160 
161 	SHA32_SCHED(W, block);
162 
163 /*
164  * Use same technique as in sha1()
165  *
166  * To improve performance, unroll the loop and consolidate assignments
167  * by changing the roles of variables "a" through "h" at each step.
168  * Note that the variable "T2" is no longer needed.
169  */
170 
171 #define M2(a, b, c, d, e, f, g, h, w)				\
172 	T1 = h  + SIGMA1(e) + Ch(e, f, g) + (*kp++) + w;	\
173 	h  = T1 + SIGMA0(a) + Ma(a, b, c); d += T1;
174 
175 #define W21(s)	W[(s+ 0) & 0xf]
176 #define W22(s)	W[(s+14) & 0xf]
177 #define W23(s)	W[(s+ 9) & 0xf]
178 #define W24(s)	W[(s+ 1) & 0xf]
179 
180 #define A2(s)	(W21(s) += sigma1(W22(s)) + W23(s) + sigma0(W24(s)))
181 
182 #define M21(w)	M2(a, b, c, d, e, f, g, h, w)
183 #define M22(w)	M2(h, a, b, c, d, e, f, g, w)
184 #define M23(w)	M2(g, h, a, b, c, d, e, f, w)
185 #define M24(w)	M2(f, g, h, a, b, c, d, e, w)
186 #define M25(w)	M2(e, f, g, h, a, b, c, d, w)
187 #define M26(w)	M2(d, e, f, g, h, a, b, c, w)
188 #define M27(w)	M2(c, d, e, f, g, h, a, b, w)
189 #define M28(w)	M2(b, c, d, e, f, g, h, a, w)
190 
191 	a = H[0]; b = H[1]; c = H[2]; d = H[3];
192 	e = H[4]; f = H[5]; g = H[6]; h = H[7];
193 
194 	M21( *wp++); M22( *wp++); M23( *wp++); M24( *wp++);
195 	M25( *wp++); M26( *wp++); M27( *wp++); M28( *wp++);
196 	M21( *wp++); M22( *wp++); M23( *wp++); M24( *wp++);
197 	M25( *wp++); M26( *wp++); M27( *wp++); M28( *wp  );
198 	M21(A2( 0)); M22(A2( 1)); M23(A2( 2)); M24(A2( 3));
199 	M25(A2( 4)); M26(A2( 5)); M27(A2( 6)); M28(A2( 7));
200 	M21(A2( 8)); M22(A2( 9)); M23(A2(10)); M24(A2(11));
201 	M25(A2(12)); M26(A2(13)); M27(A2(14)); M28(A2(15));
202 	M21(A2( 0)); M22(A2( 1)); M23(A2( 2)); M24(A2( 3));
203 	M25(A2( 4)); M26(A2( 5)); M27(A2( 6)); M28(A2( 7));
204 	M21(A2( 8)); M22(A2( 9)); M23(A2(10)); M24(A2(11));
205 	M25(A2(12)); M26(A2(13)); M27(A2(14)); M28(A2(15));
206 	M21(A2( 0)); M22(A2( 1)); M23(A2( 2)); M24(A2( 3));
207 	M25(A2( 4)); M26(A2( 5)); M27(A2( 6)); M28(A2( 7));
208 	M21(A2( 8)); M22(A2( 9)); M23(A2(10)); M24(A2(11));
209 	M25(A2(12)); M26(A2(13)); M27(A2(14)); M28(A2(15));
210 
211 	H[0] += a; H[1] += b; H[2] += c; H[3] += d;
212 	H[4] += e; H[5] += f; H[6] += g; H[7] += h;
213 }
214 
215 #include "sha64bit.c"
216 
217 #define SETBIT(s, pos)	s[(pos) >> 3] |=  (0x01 << (7 - (pos) % 8))
218 #define CLRBIT(s, pos)	s[(pos) >> 3] &= ~(0x01 << (7 - (pos) % 8))
219 #define NBYTES(nbits)	(((nbits) + 7) >> 3)
220 #define HEXLEN(nbytes)	((nbytes) << 1)
221 #define B64LEN(nbytes)	(((nbytes) % 3 == 0) ? ((nbytes) / 3) * 4 \
222 			: ((nbytes) / 3) * 4 + ((nbytes) % 3) + 1)
223 
224 /* w32mem: writes 32-bit word to memory in big-endian order */
225 static void w32mem(UCHR *mem, W32 w32)
226 {
227 	int i;
228 
229 	for (i = 0; i < 4; i++)
230 		*mem++ = (UCHR) (SR32(w32, 24-i*8) & 0xff);
231 }
232 
233 /* digcpy: writes current state to digest buffer */
234 static void digcpy(SHA *s)
235 {
236 	UINT i;
237 	UCHR *d = s->digest;
238 	W32 *p32 = (W32 *) s->H;
239 	W64 *p64 = (W64 *) s->H;
240 
241 	if (s->alg <= SHA256)
242 		for (i = 0; i < 8; i++, d += 4)
243 			w32mem(d, *p32++);
244 	else
245 		for (i = 0; i < 8; i++, d += 8) {
246 			w32mem(d, (W32) ((*p64 >> 16) >> 16));
247 			w32mem(d+4, (W32) (*p64++ & SHA32_MAX));
248 		}
249 }
250 
251 #define SHA_INIT(algo, transform) 					\
252 	do {								\
253 		memset(s, 0, sizeof(SHA));				\
254 		s->alg = algo; s->sha = sha ## transform;		\
255 		memcpy(s->H, H0 ## algo, sizeof(H0 ## algo));		\
256 		s->blocksize = SHA ## algo ## _BLOCK_BITS;		\
257 		s->digestlen = SHA ## algo ## _DIGEST_BITS >> 3;	\
258 	} while (0)
259 
260 /* sharewind: re-initializes the digest object */
261 static void sharewind(SHA *s)
262 {
263 	if      (s->alg == SHA1)   SHA_INIT(1, 1);
264 	else if (s->alg == SHA224) SHA_INIT(224, 256);
265 	else if (s->alg == SHA256) SHA_INIT(256, 256);
266 	else if (s->alg == SHA384) SHA_INIT(384, 512);
267 	else if (s->alg == SHA512) SHA_INIT(512, 512);
268 	else if (s->alg == SHA512224) SHA_INIT(512224, 512);
269 	else if (s->alg == SHA512256) SHA_INIT(512256, 512);
270 }
271 
272 /* shaopen: creates a new digest object */
273 static SHA *shaopen(int alg)
274 {
275 	SHA *s = NULL;
276 
277 	if (alg != SHA1 && alg != SHA224 && alg != SHA256 &&
278 		alg != SHA384    && alg != SHA512 &&
279 		alg != SHA512224 && alg != SHA512256)
280 		return(NULL);
281 	if (alg >= SHA384 && !sha_384_512)
282 		return(NULL);
283 	SHA_newz(0, s, 1, SHA);
284 	if (s == NULL)
285 		return(NULL);
286 	s->alg = alg;
287 	sharewind(s);
288 	return(s);
289 }
290 
291 /* shaclose: de-allocates digest object */
292 static int shaclose(SHA *s)
293 {
294 	if (s != NULL) {
295 		memset(s, 0, sizeof(SHA));
296 		SHA_free(s);
297 	}
298 	return(0);
299 }
300 
301 /* shadirect: updates state directly (w/o going through s->block) */
302 static ULNG shadirect(UCHR *bitstr, ULNG bitcnt, SHA *s)
303 {
304 	ULNG savecnt = bitcnt;
305 
306 	while (bitcnt >= s->blocksize) {
307 		s->sha(s, bitstr);
308 		bitstr += (s->blocksize >> 3);
309 		bitcnt -= s->blocksize;
310 	}
311 	if (bitcnt > 0) {
312 		memcpy(s->block, bitstr, NBYTES(bitcnt));
313 		s->blockcnt = bitcnt;
314 	}
315 	return(savecnt);
316 }
317 
318 /* shabytes: updates state for byte-aligned input data */
319 static ULNG shabytes(UCHR *bitstr, ULNG bitcnt, SHA *s)
320 {
321 	UINT offset;
322 	UINT nbits;
323 	ULNG savecnt = bitcnt;
324 
325 	offset = s->blockcnt >> 3;
326 	if (s->blockcnt + bitcnt >= s->blocksize) {
327 		nbits = s->blocksize - s->blockcnt;
328 		memcpy(s->block+offset, bitstr, nbits>>3);
329 		bitcnt -= nbits;
330 		bitstr += (nbits >> 3);
331 		s->sha(s, s->block), s->blockcnt = 0;
332 		shadirect(bitstr, bitcnt, s);
333 	}
334 	else {
335 		memcpy(s->block+offset, bitstr, NBYTES(bitcnt));
336 		s->blockcnt += bitcnt;
337 	}
338 	return(savecnt);
339 }
340 
341 /* shabits: updates state for bit-aligned input data */
342 static ULNG shabits(UCHR *bitstr, ULNG bitcnt, SHA *s)
343 {
344 	UINT i;
345 	UINT gap;
346 	ULNG nbits;
347 	UCHR buf[1<<9];
348 	UINT bufsize = sizeof(buf);
349 	ULNG bufbits = (ULNG) bufsize << 3;
350 	UINT nbytes = NBYTES(bitcnt);
351 	ULNG savecnt = bitcnt;
352 
353 	gap = 8 - s->blockcnt % 8;
354 	s->block[s->blockcnt>>3] &= ~0 << gap;
355 	s->block[s->blockcnt>>3] |= *bitstr >> (8 - gap);
356 	s->blockcnt += bitcnt < gap ? bitcnt : gap;
357 	if (bitcnt < gap)
358 		return(savecnt);
359 	if (s->blockcnt == s->blocksize)
360 		s->sha(s, s->block), s->blockcnt = 0;
361 	if ((bitcnt -= gap) == 0)
362 		return(savecnt);
363 	while (nbytes > bufsize) {
364 		for (i = 0; i < bufsize; i++)
365 			buf[i] = bitstr[i] << gap | bitstr[i+1] >> (8-gap);
366 		nbits = bitcnt < bufbits ? bitcnt : bufbits;
367 		shabytes(buf, nbits, s);
368 		bitcnt -= nbits, bitstr += bufsize, nbytes -= bufsize;
369 	}
370 	for (i = 0; i < nbytes - 1; i++)
371 		buf[i] = bitstr[i] << gap | bitstr[i+1] >> (8-gap);
372 	buf[nbytes-1] = bitstr[nbytes-1] << gap;
373 	shabytes(buf, bitcnt, s);
374 	return(savecnt);
375 }
376 
377 /* shawrite: triggers a state update using data in bitstr/bitcnt */
378 static ULNG shawrite(UCHR *bitstr, ULNG bitcnt, SHA *s)
379 {
380 	if (bitcnt < 1)
381 		return(0);
382 	if (SHA_LO32(s->lenll += bitcnt) < bitcnt)
383 		if (SHA_LO32(++s->lenlh) == 0)
384 			if (SHA_LO32(++s->lenhl) == 0)
385 				s->lenhh++;
386 	if (s->blockcnt == 0)
387 		return(shadirect(bitstr, bitcnt, s));
388 	else if (s->blockcnt % 8 == 0)
389 		return(shabytes(bitstr, bitcnt, s));
390 	else
391 		return(shabits(bitstr, bitcnt, s));
392 }
393 
394 /* shafinish: pads remaining block(s) and computes final digest state */
395 static void shafinish(SHA *s)
396 {
397 	UINT lenpos, lhpos, llpos;
398 
399 	lenpos = s->blocksize == SHA1_BLOCK_BITS ? 448 : 896;
400 	lhpos  = s->blocksize == SHA1_BLOCK_BITS ?  56 : 120;
401 	llpos  = s->blocksize == SHA1_BLOCK_BITS ?  60 : 124;
402 	SETBIT(s->block, s->blockcnt), s->blockcnt++;
403 	while (s->blockcnt > lenpos)
404 		if (s->blockcnt < s->blocksize)
405 			CLRBIT(s->block, s->blockcnt), s->blockcnt++;
406 		else
407 			s->sha(s, s->block), s->blockcnt = 0;
408 	while (s->blockcnt < lenpos)
409 		CLRBIT(s->block, s->blockcnt), s->blockcnt++;
410 	if (s->blocksize > SHA1_BLOCK_BITS) {
411 		w32mem(s->block + 112, s->lenhh);
412 		w32mem(s->block + 116, s->lenhl);
413 	}
414 	w32mem(s->block + lhpos, s->lenlh);
415 	w32mem(s->block + llpos, s->lenll);
416 	s->sha(s, s->block);
417 }
418 
419 /* shadigest: returns pointer to current digest (binary) */
420 static UCHR *shadigest(SHA *s)
421 {
422 	digcpy(s);
423 	return(s->digest);
424 }
425 
426 /* shahex: returns pointer to current digest (hexadecimal) */
427 static char *shahex(SHA *s)
428 {
429 	int i;
430 
431 	digcpy(s);
432 	s->hex[0] = '\0';
433 	if (HEXLEN((size_t) s->digestlen) >= sizeof(s->hex))
434 		return(s->hex);
435 	for (i = 0; i < s->digestlen; i++)
436 		sprintf(s->hex+i*2, "%02x", s->digest[i]);
437 	return(s->hex);
438 }
439 
440 /* map: translation map for Base 64 encoding */
441 static char map[] =
442 	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
443 
444 /* encbase64: encodes input (0 to 3 bytes) into Base 64 */
445 static void encbase64(UCHR *in, int n, char *out)
446 {
447 	UCHR byte[3] = {0, 0, 0};
448 
449 	out[0] = '\0';
450 	if (n < 1 || n > 3)
451 		return;
452 	memcpy(byte, in, n);
453 	out[0] = map[byte[0] >> 2];
454 	out[1] = map[((byte[0] & 0x03) << 4) | (byte[1] >> 4)];
455 	out[2] = map[((byte[1] & 0x0f) << 2) | (byte[2] >> 6)];
456 	out[3] = map[byte[2] & 0x3f];
457 	out[n+1] = '\0';
458 }
459 
460 /* shabase64: returns pointer to current digest (Base 64) */
461 static char *shabase64(SHA *s)
462 {
463 	int n;
464 	UCHR *q;
465 	char out[5];
466 
467 	digcpy(s);
468 	s->base64[0] = '\0';
469 	if (B64LEN((size_t) s->digestlen) >= sizeof(s->base64))
470 		return(s->base64);
471 	for (n = s->digestlen, q = s->digest; n > 3; n -= 3, q += 3) {
472 		encbase64(q, 3, out);
473 		strcat(s->base64, out);
474 	}
475 	encbase64(q, n, out);
476 	strcat(s->base64, out);
477 	return(s->base64);
478 }
479 
480 /* shadsize: returns length of digest in bytes */
481 static int shadsize(SHA *s)
482 {
483 	return(s->digestlen);
484 }
485 
486 /* shaalg: returns which SHA algorithm is being used */
487 static int shaalg(SHA *s)
488 {
489 	return(s->alg);
490 }
491 
492 /* shadup: duplicates current digest object */
493 static SHA *shadup(SHA *s)
494 {
495 	SHA *p;
496 
497 	SHA_new(0, p, 1, SHA);
498 	if (p == NULL)
499 		return(NULL);
500 	memcpy(p, s, sizeof(SHA));
501 	return(p);
502 }
503 
504 /* shadump: dumps digest object to a human-readable ASCII file */
505 static int shadump(char *file, SHA *s)
506 {
507 	int i, j;
508 	SHA_FILE *f;
509 	UCHR *p = shadigest(s);
510 
511 	if (file == NULL || strlen(file) == 0)
512 		f = SHA_stdout();
513 	else if ((f = SHA_open(file, "w")) == NULL)
514 		return(0);
515 	SHA_fprintf(f, "alg:%d\nH", s->alg);
516 	for (i = 0; i < 8; i++)
517 		for (j = 0; j < (s->alg <= 256 ? 4 : 8); j++)
518 			SHA_fprintf(f, "%s%02x", j==0 ? ":" : "", *p++);
519 	SHA_fprintf(f, "\nblock");
520 	for (i = 0; i < (int) (s->blocksize >> 3); i++)
521 		SHA_fprintf(f, ":%02x", s->block[i]);
522 	SHA_fprintf(f, "\nblockcnt:%u\n", s->blockcnt);
523 	SHA_fprintf(f, "lenhh:%lu\nlenhl:%lu\nlenlh:%lu\nlenll:%lu\n",
524 		(ULNG) LO32(s->lenhh), (ULNG) LO32(s->lenhl),
525 		(ULNG) LO32(s->lenlh), (ULNG) LO32(s->lenll));
526 	if (f != SHA_stdout())
527 		SHA_close(f);
528 	return(1);
529 }
530 
531 /* fgetstr: reads (and returns pointer to) next line of file */
532 static char *fgetstr(char *line, UINT maxsize, SHA_FILE *f)
533 {
534 	char *p;
535 
536 	if (SHA_feof(f) || maxsize == 0)
537 		return(NULL);
538 	for (p = line; !SHA_feof(f) && maxsize > 1; maxsize--)
539 		if ((*p++ = SHA_getc(f)) == '\n')
540 			break;
541 	*p = '\0';
542 	return(line);
543 }
544 
545 /* empty: returns true if line contains only whitespace characters */
546 static int empty(char *line)
547 {
548 	char *p;
549 
550 	for (p = line; *p; p++)
551 		if (!isspace(*p))
552 			return(0);
553 	return(1);
554 }
555 
556 /* getval: null-terminates field value, and sets pointer to rest of line */
557 static char *getval(char *line, char **pprest)
558 {
559 	char *p, *v;
560 
561 	for (v = line; *v == ':' || isspace(*v); v++)
562 		;
563 	for (p = v; *p; p++) {
564 		if (*p == ':' || isspace(*p)) {
565 			*p++ = '\0';
566 			break;
567 		}
568 	}
569 	*pprest = p;
570 	return(p == v ? NULL : v);
571 }
572 
573 /* types of values present in dump file */
574 #define T_C 1			/* character */
575 #define T_I 2			/* normal integer */
576 #define T_L 3			/* 32-bit value */
577 #define T_Q 4			/* 64-bit value */
578 
579 /* ldvals: checks next line in dump file against tag, and loads values */
580 static int ldvals(
581 	SHA_FILE *f,
582 	const char *tag,
583 	int type,
584 	void *pval,
585 	int reps,
586 	int base)
587 {
588 	char *p, *pr, line[512];
589 	UCHR *pc = (UCHR *) pval; UINT *pi = (UINT *) pval;
590 	W32  *pl = (W32  *) pval; W64  *pq = (W64  *) pval;
591 
592 	while ((p = fgetstr(line, sizeof(line), f)) != NULL)
593 		if (line[0] != '#' && !empty(line))
594 			break;
595 	if (p == NULL || strcmp(getval(line, &pr), tag) != 0)
596 		return(0);
597 	while (reps-- > 0) {
598 		if ((p = getval(pr, &pr)) == NULL)
599 			return(1);
600 		switch (type) {
601 		case T_C: *pc++ = (UCHR) strtoul(p, NULL, base); break;
602 		case T_I: *pi++ = (UINT) strtoul(p, NULL, base); break;
603 		case T_L: *pl++ = (W32 ) strtoul(p, NULL, base); break;
604 		case T_Q: *pq++ = (W64 ) strto64(p            ); break;
605 		}
606 	}
607 	return(1);
608 }
609 
610 /* closeall: closes dump file and de-allocates digest object */
611 static SHA *closeall(SHA_FILE *f, SHA *s)
612 {
613 	if (f != NULL && f != SHA_stdin())
614 		SHA_close(f);
615 	if (s != NULL)
616 		shaclose(s);
617 	return(NULL);
618 }
619 
620 /* shaload: creates digest object corresponding to contents of dump file */
621 static SHA *shaload(char *file)
622 {
623 	int alg;
624 	SHA *s = NULL;
625 	SHA_FILE *f;
626 
627 	if (file == NULL || strlen(file) == 0)
628 		f = SHA_stdin();
629 	else if ((f = SHA_open(file, "r")) == NULL)
630 		return(NULL);
631 	if (
632 		/* avoid parens by exploiting precedence of (type)&-> */
633 		!ldvals(f,"alg",T_I,(VP)&alg,1,10)			||
634 		((s = shaopen(alg)) == NULL)				||
635 		!ldvals(f,"H",alg<=SHA256?T_L:T_Q,(VP)s->H,8,16)	||
636 		!ldvals(f,"block",T_C,(VP)s->block,s->blocksize/8,16)	||
637 		!ldvals(f,"blockcnt",T_I,(VP)&s->blockcnt,1,10)		||
638 		(alg <= SHA256 && s->blockcnt >= SHA1_BLOCK_BITS)	||
639 		(alg >= SHA384 && s->blockcnt >= SHA384_BLOCK_BITS)	||
640 		!ldvals(f,"lenhh",T_L,(VP)&s->lenhh,1,10)		||
641 		!ldvals(f,"lenhl",T_L,(VP)&s->lenhl,1,10)		||
642 		!ldvals(f,"lenlh",T_L,(VP)&s->lenlh,1,10)		||
643 		!ldvals(f,"lenll",T_L,(VP)&s->lenll,1,10)
644 	)
645 		return(closeall(f, s));
646 	if (f != SHA_stdin())
647 		SHA_close(f);
648 	return(s);
649 }
650 
651 /* hmacopen: creates a new HMAC-SHA digest object */
652 static HMAC *hmacopen(int alg, UCHR *key, UINT keylen)
653 {
654 	UINT i;
655 	HMAC *h;
656 
657 	SHA_newz(0, h, 1, HMAC);
658 	if (h == NULL)
659 		return(NULL);
660 	if ((h->isha = shaopen(alg)) == NULL) {
661 		SHA_free(h);
662 		return(NULL);
663 	}
664 	if ((h->osha = shaopen(alg)) == NULL) {
665 		shaclose(h->isha);
666 		SHA_free(h);
667 		return(NULL);
668 	}
669 	if (keylen <= h->osha->blocksize / 8)
670 		memcpy(h->key, key, keylen);
671 	else {
672 		if ((h->ksha = shaopen(alg)) == NULL) {
673 			shaclose(h->isha);
674 			shaclose(h->osha);
675 			SHA_free(h);
676 			return(NULL);
677 		}
678 		shawrite(key, keylen * 8, h->ksha);
679 		shafinish(h->ksha);
680 		memcpy(h->key, shadigest(h->ksha), h->ksha->digestlen);
681 		shaclose(h->ksha);
682 	}
683 	for (i = 0; i < h->osha->blocksize / 8; i++)
684 		h->key[i] ^= 0x5c;
685 	shawrite(h->key, h->osha->blocksize, h->osha);
686 	for (i = 0; i < h->isha->blocksize / 8; i++)
687 		h->key[i] ^= (0x5c ^ 0x36);
688 	shawrite(h->key, h->isha->blocksize, h->isha);
689 	memset(h->key, 0, sizeof(h->key));
690 	return(h);
691 }
692 
693 /* hmacwrite: triggers a state update using data in bitstr/bitcnt */
694 static ULNG hmacwrite(UCHR *bitstr, ULNG bitcnt, HMAC *h)
695 {
696 	return(shawrite(bitstr, bitcnt, h->isha));
697 }
698 
699 /* hmacfinish: computes final digest state */
700 static void hmacfinish(HMAC *h)
701 {
702 	shafinish(h->isha);
703 	shawrite(shadigest(h->isha), h->isha->digestlen * 8, h->osha);
704 	shaclose(h->isha);
705 	shafinish(h->osha);
706 }
707 
708 /* hmacdigest: returns pointer to digest (binary) */
709 static UCHR *hmacdigest(HMAC *h)
710 {
711 	return(shadigest(h->osha));
712 }
713 
714 /* hmachex: returns pointer to digest (hexadecimal) */
715 static char *hmachex(HMAC *h)
716 {
717 	return(shahex(h->osha));
718 }
719 
720 /* hmacbase64: returns pointer to digest (Base 64) */
721 static char *hmacbase64(HMAC *h)
722 {
723 	return(shabase64(h->osha));
724 }
725 
726 /* hmacclose: de-allocates digest object */
727 static int hmacclose(HMAC *h)
728 {
729 	if (h != NULL) {
730 		shaclose(h->osha);
731 		memset(h, 0, sizeof(HMAC));
732 		SHA_free(h);
733 	}
734 	return(0);
735 }
736