d03ab969 |
1 | /* -*-c-*- |
2 | * |
099355bc |
3 | * $Id: noise.h,v 1.3 1999/12/22 15:57:55 mdw Exp $ |
d03ab969 |
4 | * |
099355bc |
5 | * Acquisition of environmental noise (Unix-specific) |
d03ab969 |
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: noise.h,v $ |
099355bc |
33 | * Revision 1.3 1999/12/22 15:57:55 mdw |
34 | * Label system-specific parts more clearly. |
35 | * |
b3f05084 |
36 | * Revision 1.2 1999/12/10 23:29:48 mdw |
37 | * Change header file guard names. |
38 | * |
d03ab969 |
39 | * Revision 1.1 1999/09/03 08:41:12 mdw |
40 | * Initial import. |
41 | * |
42 | */ |
43 | |
b3f05084 |
44 | #ifndef CATACOMB_NOISE_H |
45 | #define CATACOMB_NOISE_H |
d03ab969 |
46 | |
47 | #ifdef __cplusplus |
48 | extern "C" { |
49 | #endif |
50 | |
51 | /*----- Header files ------------------------------------------------------*/ |
52 | |
53 | #include <sys/types.h> |
54 | |
b3f05084 |
55 | #ifndef CATACOMB_RAND_H |
d03ab969 |
56 | # include "rand.h" |
57 | #endif |
58 | |
59 | /*----- Noise source definition -------------------------------------------*/ |
60 | |
61 | extern rand_source noise_source; |
62 | |
63 | /*----- Magic numbers -----------------------------------------------------*/ |
64 | |
65 | #define NOISE_NOSETUID ((uid_t)-1) |
66 | #define NOISE_NOSETGID ((gid_t)-1) |
67 | |
68 | /*----- Functions provided ------------------------------------------------*/ |
69 | |
70 | /* --- @noise_timer@ --- * |
71 | * |
72 | * Arguments: @rand_pool *r@ = pointer to a randomness pool |
73 | * |
74 | * Returns: Nonzero if some randomness was contributed. |
75 | * |
76 | * Use: Contributes the current time to the randomness pool. |
77 | * A guess at the number of useful bits contributed is made, |
78 | * based on first and second order bit differences. This isn't |
79 | * ever-so reliable, but it's better than nothing. |
80 | */ |
81 | |
82 | extern int noise_timer(rand_pool */*r*/); |
83 | |
84 | /* --- @noise_devrandom@ --- * |
85 | * |
86 | * Arguments: @rand_pool *r@ = pointer to a randomness pool |
87 | * |
88 | * Returns: Nonzero if some randomness was contributed. |
89 | * |
90 | * Use: Attempts to obtain some randomness from the system entropy |
91 | * pool. All bits from the device are assumed to be good. |
92 | */ |
93 | |
94 | extern int noise_devrandom(rand_pool */*r*/); |
95 | |
96 | /* --- @noise_setid@ --- * |
97 | * |
98 | * Arguments: @uid_t uid@ = uid to set |
99 | * @gid_t gid@ = gid to set |
100 | * |
101 | * Returns: --- |
102 | * |
103 | * Use: Sets the user and group ids to be used by @noise_filter@ |
104 | * when running child processes. This is useful to avoid |
105 | * giving shell commands (even carefully written ones) undue |
099355bc |
106 | * privileges. This interface is Unix-specific. |
d03ab969 |
107 | */ |
108 | |
109 | extern void noise_setid(uid_t /*uid*/, gid_t /*gid*/); |
110 | |
111 | /* --- @noise_filter@ --- * |
112 | * |
113 | * Arguments: @rand_pool *r@ = pointer to a randomness pool |
114 | * @int good@ = number of good bits per 1024 bits |
115 | * @const char *c@ = shell command to run |
116 | * |
117 | * Returns: Nonzero if some randomness was contributed. |
118 | * |
119 | * Use: Attempts to execute a shell command, and dump it into the |
120 | * randomness pool. A very rough estimate of the number of |
121 | * good bits is made, based on the size of the command's output. |
122 | * This function calls @waitpid@, so be careful. Before execing |
123 | * the command, the process uid and gid are set to the values |
124 | * given to @noise_setid@, and an attempt is made to reset the |
125 | * list of supplementary groups. The environment passed to |
126 | * the command has been severly lobotimized. If the command |
127 | * fails to complete within a short time period, it is killed. |
128 | * Paranoid use of close-on-exec flags for file descriptors is |
129 | * recommended. |
099355bc |
130 | * |
131 | * This interface is Unix-specific. |
d03ab969 |
132 | */ |
133 | |
134 | extern int noise_filter(rand_pool */*r*/, int /*good*/, const char */*c*/); |
135 | |
136 | /* --- @noise_acquire@ --- * |
137 | * |
138 | * Arguments: @rand_pool *r@ = pointer to a randomness pool |
139 | * |
140 | * Returns: --- |
141 | * |
142 | * Use: Acquires some randomness from somewhere. |
143 | */ |
144 | |
145 | extern void noise_acquire(rand_pool */*r*/); |
146 | |
147 | /*----- That's all, folks -------------------------------------------------*/ |
148 | |
149 | #ifdef __cplusplus |
150 | } |
151 | #endif |
152 | |
153 | #endif |