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progs/perftest.c: Use from Glibc syscall numbers.
[catacomb] / symm / cmac.h
1 /* -*-c-*-
2 *
3 * The CMAC message-authentication code
4 *
5 * (c) 2017 Straylight/Edgeware
6 */
7
8 /*----- Licensing notice --------------------------------------------------*
9 *
10 * This file is part of Catacomb.
11 *
12 * Catacomb is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Library General Public License as
14 * published by the Free Software Foundation; either version 2 of the
15 * License, or (at your option) any later version.
16 *
17 * Catacomb is distributed in the hope that it will be useful,
18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20 * GNU Library General Public License for more details.
21 *
22 * You should have received a copy of the GNU Library General Public
23 * License along with Catacomb; if not, write to the Free
24 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
25 * MA 02111-1307, USA.
26 */
27
28 /*----- Notes on CMAC -----------------------------------------------------*
29 *
30 * CMAC was designed in 2003 by Tetsu Iwata and Kaoru Kurosawa as a reliable
31 * general purpose message-authentication code based on CBC-MAC. CBC-MAC's
32 * deficiencies have been well known since at least 2000 when Bellare,
33 * Kilian, and Rogaway proved its security on constant-length messages.
34 * Black and Rogaway in 2000 described a number of three-key constructions
35 * for extending CBC-MAC's domain securely to arbitrary strings, culminating
36 * in a mode they named `XCBC', which uses a blockcipher key and two XOR
37 * masks. Iwata and Kurosawa's original proposal, named `OMAC', refined XCBC
38 * by deriving the masks from the key, producing a `one-key MAC'. Bellare,
39 * Rogaway, and Wagner slightly simplified the way the masks were derived
40 * when they used OMAC as a part of their EAX authenticated-encryption mode,
41 * and this change was adopted by NIST when they standardized OMAC, under the
42 * name `CMAC', in SP800-38B.
43 *
44 * NIST specify CMAC only for 64- and 128-bit blockciphers. This
45 * implementation extends it to other lengths in the obvious way.
46 */
47
48 #ifndef CATACOMB_CMAC_H
49 #define CATACOMB_CMAC_H
50
51 #ifdef __cplusplus
52 extern "C" {
53 #endif
54
55 /*----- Header files ------------------------------------------------------*/
56
57 #include <stddef.h>
58
59 #include <mLib/bits.h>
60
61 #ifndef CATACOMB_GMAC_H
62 # include "gmac.h"
63 #endif
64
65 #ifndef CATACOMB_RSVR_H
66 # include "rsvr.h"
67 #endif
68
69 /*----- Low-level OMAC declarations ---------------------------------------*/
70
71 /* --- @OMAC_DECL@ --- *
72 *
73 * Arguments: @PRE@, @pre@ = prefixes for the underlying block cipher
74 *
75 * Use: Defines low-level implementation for the OMAC message-
76 * authentication mode.
77 */
78
79 #define OMAC_DECL(PRE, pre) \
80 \
81 /* Buffering policy for OMAC. */ \
82 extern const rsvr_policy pre##_omacpolicy; \
83 \
84 /* --- @pre_omacmasks@ --- * \
85 * \
86 * Arguments: @pre_ctx *k@ = pointer to expanded blockcipher key \
87 * @uint32 *m0, *m1@ = buffers to store the masks \
88 * \
89 * Returns: --- \
90 * \
91 * Use: Initialize the OMAC masks. The mask buffers are \
92 * @PRE_BLKSZ/4@ words long. The mmask @m0@ is applied to \
93 * messages which are a whole number of blocks long; @m1@ \
94 * is applied to messages with an incomplete final block, \
95 * following the 10* padding. \
96 */ \
97 \
98 extern void pre##_omacmasks(pre##_ctx */*k*/, \
99 uint32 */*m0*/, uint32 */*m1*/); \
100 \
101 /* --- @pre_omacdone@ --- * \
102 * \
103 * Arguments: @pre_ctx *k@ = pointer to expanded blockcipher key \
104 * @const uint32 *m0, *m1@ = masks \
105 * @uint32 *a@ = accumulator state to update \
106 * @octet *p@ = pointer to input buffer (clobbered) \
107 * @unsigned n@ = size of input buffer (no more than \
108 * @PRE_BLKSZ@) \
109 * \
110 * Returns: --- \
111 * \
112 * Use: Update and finalize the OMAC hash state with the last \
113 * few bytes of input. The final tag is left in @a@. \
114 */ \
115 \
116 extern void pre##_omacdone(pre##_ctx */*k*/, \
117 const uint32 */*m0*/, const uint32 */*m1*/, \
118 uint32 */*a*/, octet */*p*/, unsigned /*n*/);
119
120 /*----- Macros ------------------------------------------------------------*/
121
122 /* --- @CMAC_DECL@ --- *
123 *
124 * Arguments: @PRE@, @pre@ = prefixes for the underlying block cipher
125 *
126 * Use: Creates declarations for CMAC message-authentication mode.
127 */
128
129 #define CMAC_DECL(PRE, pre) \
130 \
131 OMAC_DECL(PRE, pre) \
132 \
133 typedef struct pre##_cmackey { \
134 pre##_ctx ctx; /* Underlying cipher context */ \
135 uint32 m0[PRE##_BLKSZ/4], m1[PRE##_BLKSZ/4]; /* Final block masks */ \
136 } pre##_cmackey; \
137 \
138 typedef struct pre##_cmacctx { \
139 pre##_cmackey k; /* Processed key material */ \
140 uint32 a[PRE##_BLKSZ/4]; /* Chaining state */ \
141 octet b[PRE##_BLKSZ]; /* Input buffer */ \
142 unsigned off; /* Offset into buffered data */ \
143 } pre##_cmacctx; \
144 \
145 /* --- @pre_cmacsetkey@ --- * \
146 * \
147 * Arguments: @pre_cmackey *key@ = pointer to CMAC key block \
148 * @ocnst void *k@ = pointer to key material \
149 * @size_t ksz@ = size of key material \
150 * \
151 * Returns: --- \
152 * \
153 * Use: Initializes a CMAC key. This can be used for several \
154 * MAC operations. \
155 */ \
156 \
157 extern void pre##_cmacsetkey(pre##_cmackey */*key*/, \
158 const void */*k*/, size_t /*ksz*/); \
159 \
160 /* --- @pre##_cmacinit@ --- * \
161 * \
162 * Arguments: @pre_cmacctx *ctx@ = pointer to context block \
163 * @pre_cmackey *k@ = key block \
164 * \
165 * Returns: --- \
166 * \
167 * Use: Initializes a CMAC context ready to process a message. \
168 * It's not necessary to keep the key around. \
169 */ \
170 \
171 extern void pre##_cmacinit(pre##_cmacctx */*ctx*/, \
172 const pre##_cmackey */*k*/); \
173 \
174 /* --- @pre_cmachash@ --- * \
175 * \
176 * Arguments: @pre_cmacctx *ctx@ = pointer to CMAC context block \
177 * @ocnst void *p@ = pointer to message buffer \
178 * @size_t sz@ = size of message buffer \
179 * \
180 * Returns: --- \
181 * \
182 * Use: Hashes some input data. \
183 */ \
184 \
185 extern void pre##_cmachash(pre##_cmacctx */*ctx*/, \
186 const void */*p*/, size_t /*sz*/); \
187 \
188 /* --- @pre_cmacdone@ --- * \
189 * \
190 * Arguments: @pre_cmacctx *ctx@ = pointer to CMAC context block \
191 * @void *t@ = where to write the tag \
192 * \
193 * Returns: --- \
194 * \
195 * Use: Finishes a MAC operation and produces the tag. \
196 */ \
197 \
198 extern void pre##_cmacdone(pre##_cmacctx */*ctx*/, void */*t*/); \
199 \
200 /* --- Generic MAC interface --- */ \
201 \
202 extern const gcmac pre##_cmac;
203
204 /*----- That's all, folks -------------------------------------------------*/
205
206 #ifdef __cplusplus
207 }
208 #endif
209
210 #endif
Catacomb cryptographic library