e9026a0a |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: gdsa.h,v 1.1 2004/04/04 19:42:59 mdw Exp $ |
4 | * |
5 | * Generalized version of DSA |
6 | * |
7 | * (c) 2004 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: gdsa.h,v $ |
33 | * Revision 1.1 2004/04/04 19:42:59 mdw |
34 | * Add set -e. |
35 | * |
36 | */ |
37 | |
38 | #ifndef CATACOMB_GDSA_H |
39 | #define CATACOMB_GDSA_H |
40 | |
41 | #ifdef __cplusplus |
42 | extern "C" { |
43 | #endif |
44 | |
45 | /*----- Header files ------------------------------------------------------*/ |
46 | |
47 | #ifndef CATACOMB_GHASH_H |
48 | # include "ghash.h" |
49 | #endif |
50 | |
51 | #ifndef CATACOMB_GROUP_H |
52 | # include "group.h" |
53 | #endif |
54 | |
55 | /*----- Data structures ---------------------------------------------------*/ |
56 | |
57 | /* --- GDSA context --- * |
58 | * |
59 | * You don't need to fill in all of this stuff. See the description of the |
60 | * function you want to use to find out what members are needed. |
61 | */ |
62 | |
63 | typedef struct gdsa { |
64 | group *g; /* The group we work in */ |
65 | mp *u; /* Private key, for signing */ |
66 | ge *p; /* Public key, for verifying */ |
67 | grand *r; /* Random number source */ |
68 | const gchash *h; /* Hash function */ |
69 | } gdsa; |
70 | |
71 | /* --- GDSA signatures --- */ |
72 | |
73 | typedef struct gdsa_sig { mp *r, *s; } gdsa_sig; |
74 | #define GDSA_SIG_INIT { MP_NEW, MP_NEW } |
75 | |
76 | /*----- Functions provided ------------------------------------------------*/ |
77 | |
78 | /* --- @gdsa_beginhash@ --- * |
79 | * |
80 | * Arguments: @const gdsa *c@ = pointer to the context structure |
81 | * |
82 | * Returns: A hashing context for you to hash the message. |
83 | * |
84 | * Use: Initializes a hash function correctly for you to hash a |
85 | * message. Requires @h@. |
86 | */ |
87 | |
88 | extern ghash *gdsa_beginhash(const gdsa */*c*/); |
89 | |
90 | /* --- @gdsa_endhash@ --- * |
91 | * |
92 | * Arguments: @const gdsa *c@ = pointer to the context structure |
93 | * @ghash *h@ = the hashing context |
94 | * |
95 | * Returns: --- |
96 | * |
97 | * Use: Does any final thing that DSA wants to do when hashing a |
98 | * message. (Actually, there's nothing.) The hashing context |
99 | * isn't finalized. |
100 | */ |
101 | |
102 | extern void gdsa_endhash(gdsa */*c*/, ghash */*h*/); |
103 | |
104 | /* --- @gdsa_sign@ --- * |
105 | * |
106 | * Arguments: @const gdsa *c@ = my context structure |
107 | * @gdsa_sig *s@ = where to put the signature (initialized) |
108 | * @const void *m@ = pointer to message hash |
109 | * @mp *k@ = random exponent for this message or null |
110 | * |
111 | * Returns: --- |
112 | * |
113 | * Use: Signs a message. Requires @g@, @u@, @h@, and @r@ if @k@ is |
114 | * null. This is a better idea than inventing @k@ yourself. |
115 | */ |
116 | |
117 | extern void gdsa_sign(const gdsa */*c*/, gdsa_sig */*s*/, |
118 | const void */*m*/, mp */*k*/); |
119 | |
120 | /* --- @gdsa_verify@ --- * |
121 | * |
122 | * Arguments: @const gdsa *c@ = my context structure |
123 | * @const gdsa_sig *s@ = the signature to verify |
124 | * @const void *m@ = pointer to message hash |
125 | * |
126 | * Returns: Zero if OK, negative on failure. |
127 | * |
128 | * Use: Checks a signature on a message, Requires @g@, @p@, @h@. |
129 | */ |
130 | |
131 | extern int gdsa_verify(const gdsa */*c*/, const gdsa_sig */*s*/, |
132 | const void */*m*/); |
133 | |
134 | /*----- That's all, folks -------------------------------------------------*/ |
135 | |
136 | #ifdef __cplusplus |
137 | } |
138 | #endif |
139 | |
140 | #endif |