projects / u / mdw / catacomb / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Add an internal-representation no-op function.
[u/mdw/catacomb] / hash.h
1 /* -*-c-*-
2 *
3 * $Id: hash.h,v 1.3 2000/06/17 11:23:27 mdw Exp $
4 *
5 * Generic handling for message digest functions
6 *
7 * (c) 1998 Straylight/Edgeware
8 */
9
10 /*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of Catacomb.
13 *
14 * Catacomb is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
18 *
19 * Catacomb is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
25 * License along with Catacomb; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30 /*----- Revision history --------------------------------------------------*
31 *
32 * $Log: hash.h,v $
33 * Revision 1.3 2000/06/17 11:23:27 mdw
34 * Portability fix for broken compilers.
35 *
36 * Revision 1.2 1999/12/10 23:16:40 mdw
37 * Split mode macros into interface and implementation.
38 *
39 * Revision 1.1 1999/09/03 08:41:12 mdw
40 * Initial import.
41 *
42 */
43
44 #ifndef CATACOMB_HASH_H
45 #define CATACOMB_HASH_H
46
47 #ifdef __cplusplus
48 extern "C" {
49 #endif
50
51 /*----- Header files ------------------------------------------------------*/
52
53 #include <string.h>
54
55 #include <mLib/bits.h>
56
57 /*----- Macros ------------------------------------------------------------*/
58
59 /* --- @HASH_BUFFER@ --- *
60 *
61 * Arguments: @PRE@, @pre@ = prefixes for hash-specific definitions
62 * @ictx@ = pointer to context block for the hash
63 * @ibuf@ = pointer to input data to hash
64 * @isz@ = size of buffer
65 *
66 * Use: Handles buffering of input data to a hash function. The
67 * hash's compression function is called when the buffer is
68 * full. Note that the compression function can be called on
69 * data which is at odd alignments; it is expected to cope
70 * gracefully with this (possibly by copying the data into its
71 * internal buffer before starting).
72 */
73
74 #define HASH_BUFFER(PRE, pre, ictx, ibuf, isz) do { \
75 pre##_ctx *_bctx = (ictx); \
76 size_t _bsz = (isz); \
77 const octet *_bbuf = (octet *)(ibuf); \
78 \
79 /* --- Add on the size done so far --- * \
80 * \
81 * Messy, because trapping overflow is difficult when you don't know \
82 * how many bits you've actually got. \
83 */ \
84 \
85 { \
86 uint32 _l = U32(_bsz); \
87 uint32 _h = ((_bsz & ~MASK32) >> 16) >> 16; \
88 _bctx->nh += _h; \
89 _bctx->nl += _l; \
90 if (_bctx->nl < _l || _bctx->nl & ~MASK32) \
91 _bctx->nh++; \
92 } \
93 \
94 /* --- Handle very small contributions --- */ \
95 \
96 if (_bctx->off + _bsz < PRE##_BUFSZ) { \
97 memcpy(_bctx->buf + _bctx->off, _bbuf, _bsz); \
98 _bctx->off += _bsz; \
99 } else { \
100 \
101 /* --- Handle an initial partial buffer --- */ \
102 \
103 if (_bctx->off) { \
104 size_t s = PRE##_BUFSZ - _bctx->off; \
105 memcpy(_bctx->buf + _bctx->off, _bbuf, s); \
106 pre##_compress(_bctx, _bctx->buf); \
107 _bsz -= s; _bbuf += s; \
108 } \
109 \
110 /* --- Do whole buffers while we can --- */ \
111 \
112 while (_bsz >= PRE##_BUFSZ) { \
113 pre##_compress(_bctx, _bbuf); \
114 _bsz -= PRE##_BUFSZ; _bbuf += PRE##_BUFSZ; \
115 } \
116 \
117 /* --- And wrap up at the end --- */ \
118 \
119 if (_bsz) \
120 memcpy(_bctx->buf, _bbuf, _bsz); \
121 _bctx->off = _bsz; \
122 } \
123 } while (0)
124
125 /* --- @HASH_PAD@ --- *
126 *
127 * Arguments: @PRE@, @pre@ = prefixes for hash-specific definitions
128 * @ictx@ = pointer to context block for the hash
129 * @term@ = terminator character to write following the data
130 * @pad@ = pad character to fill with
131 * @diff@ = size of space to leave at the end of the last block
132 *
133 * Use: Does padding for message digest functions.
134 */
135
136 #define HASH_PAD(PRE, pre, ictx, term, pad, diff) do { \
137 pre##_ctx *_pctx = (ictx); \
138 \
139 _pctx->buf[_pctx->off] = term; \
140 _pctx->off++; \
141 if (_pctx->off > PRE##_BUFSZ - diff) { \
142 if (_pctx->off < PRE##_BUFSZ) \
143 memset(_pctx->buf + _pctx->off, pad, PRE##_BUFSZ - _pctx->off); \
144 pre##_compress(_pctx, _pctx->buf); \
145 memset(_pctx->buf, pad, PRE##_BUFSZ - diff); \
146 } else \
147 memset(_pctx->buf + _pctx->off, pad, \
148 PRE##_BUFSZ - _pctx->off - diff); \
149 } while (0)
150
151 /* --- @HASH_MD5STRENGTH@ --- *
152 *
153 * Arguments: @PRE@, @pre@ = prefixes for hash-specific definitions
154 * @ictx@ = pointer to context block for the hash
155 *
156 * Use: Does MD5-style MD strengthening. The data is terminated
157 * by a single set bit, padded with zero bits, and then a 64-
158 * bit length is written, little-end first.
159 */
160
161 #define HASH_MD5STRENGTH(PRE, pre, ictx) do { \
162 pre##_ctx *_mctx = (ictx); \
163 HASH_PAD(PRE, pre, _mctx, 0x80u, 0, 8); \
164 STORE32_L(_mctx->buf + PRE##_BUFSZ - 8, _mctx->nl << 3); \
165 STORE32_L(_mctx->buf + PRE##_BUFSZ - 4, \
166 (_mctx->nl >> 29) | (_mctx->nh << 3)); \
167 pre##_compress(_mctx, _mctx->buf); \
168 } while (0)
169
170 /* --- @HASH_TEST@ --- *
171 *
172 * Arguments: @PRE@, @pre@ = prefixes for hash-specfic definitions
173 *
174 * Use: Standard test rig for hash functions.
175 */
176
177 #ifdef TEST_RIG
178
179 #include <mLib/quis.h>
180 #include <mLib/testrig.h>
181
182 #define HASH_TEST(PRE, pre) \
183 \
184 static int verify(dstr *v) \
185 { \
186 pre##_ctx ctx; \
187 int ok = 1; \
188 int i; \
189 octet *p; \
190 int szs[] = { 1, 7, 192, -1, 0 }, *ip; \
191 size_t sz; \
192 dstr d; \
193 \
194 dstr_create(&d); \
195 dstr_ensure(&d, PRE##_HASHSZ); \
196 d.len = PRE##_HASHSZ; \
197 \
198 for (ip = szs; *ip; ip++) { \
199 i = *ip; \
200 sz = v[0].len; \
201 if (i == -1) \
202 i = sz; \
203 if (i > sz) \
204 continue; \
205 p = (octet *)v[0].buf; \
206 pre##_init(&ctx); \
207 while (sz) { \
208 if (i > sz) \
209 i = sz; \
210 pre##_hash(&ctx, p, i); \
211 p += i; \
212 sz -= i; \
213 } \
214 pre##_done(&ctx, d.buf); \
215 if (memcmp(d.buf, v[1].buf, PRE##_HASHSZ) != 0) { \
216 printf("\nfail:\n\tstep = %i\n\tinput = `%s'\n\texpected = ", \
217 *ip, v[0].buf); \
218 type_hex.dump(&v[1], stdout); \
219 fputs("\n\tcomputed = ", stdout); \
220 type_hex.dump(&d, stdout); \
221 putchar('\n'); \
222 ok = 0; \
223 } \
224 } \
225 \
226 dstr_destroy(&d); \
227 return (ok); \
228 } \
229 \
230 static test_chunk defs[] = { \
231 { #pre, verify, { &type_string, &type_hex, 0 } }, \
232 { 0, 0, { 0 } } \
233 }; \
234 \
235 int main(int argc, char *argv[]) \
236 { \
237 ego(argv[0]); \
238 test_run(argc, argv, defs, SRCDIR"/tests/" #pre); \
239 return (0); \
240 }
241
242 #else
243 # define HASH_TEST(PRE, pre)
244 #endif
245
246 /*----- That's all, folks -------------------------------------------------*/
247
248 #ifdef __cplusplus
249 }
250 #endif
251
252 #endif
Catacomb cryptographic library (downstream of http://git.distorted.org.uk/~mdw/catacomb/)