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-rw-r--r--libraries/irrlicht-1.8/source/Irrlicht/aesGladman/prng.cpp292
1 files changed, 146 insertions, 146 deletions
diff --git a/libraries/irrlicht-1.8/source/Irrlicht/aesGladman/prng.cpp b/libraries/irrlicht-1.8/source/Irrlicht/aesGladman/prng.cpp
index d5800b3..708cb08 100644
--- a/libraries/irrlicht-1.8/source/Irrlicht/aesGladman/prng.cpp
+++ b/libraries/irrlicht-1.8/source/Irrlicht/aesGladman/prng.cpp
@@ -1,146 +1,146 @@
1/* 1/*
2 --------------------------------------------------------------------------- 2 ---------------------------------------------------------------------------
3 Copyright (c) 2002, Dr Brian Gladman < >, Worcester, UK. 3 Copyright (c) 2002, Dr Brian Gladman < >, Worcester, UK.
4 All rights reserved. 4 All rights reserved.
5 5
6 LICENSE TERMS 6 LICENSE TERMS
7 7
8 The free distribution and use of this software in both source and binary 8 The free distribution and use of this software in both source and binary
9 form is allowed (with or without changes) provided that: 9 form is allowed (with or without changes) provided that:
10 10
11 1. distributions of this source code include the above copyright 11 1. distributions of this source code include the above copyright
12 notice, this list of conditions and the following disclaimer; 12 notice, this list of conditions and the following disclaimer;
13 13
14 2. distributions in binary form include the above copyright 14 2. distributions in binary form include the above copyright
15 notice, this list of conditions and the following disclaimer 15 notice, this list of conditions and the following disclaimer
16 in the documentation and/or other associated materials; 16 in the documentation and/or other associated materials;
17 17
18 3. the copyright holder's name is not used to endorse products 18 3. the copyright holder's name is not used to endorse products
19 built using this software without specific written permission. 19 built using this software without specific written permission.
20 20
21 ALTERNATIVELY, provided that this notice is retained in full, this product 21 ALTERNATIVELY, provided that this notice is retained in full, this product
22 may be distributed under the terms of the GNU General Public License (GPL), 22 may be distributed under the terms of the GNU General Public License (GPL),
23 in which case the provisions of the GPL apply INSTEAD OF those given above. 23 in which case the provisions of the GPL apply INSTEAD OF those given above.
24 24
25 DISCLAIMER 25 DISCLAIMER
26 26
27 This software is provided 'as is' with no explicit or implied warranties 27 This software is provided 'as is' with no explicit or implied warranties
28 in respect of its properties, including, but not limited to, correctness 28 in respect of its properties, including, but not limited to, correctness
29 and/or fitness for purpose. 29 and/or fitness for purpose.
30 --------------------------------------------------------------------------- 30 ---------------------------------------------------------------------------
31 Issue Date: 24/01/2003 31 Issue Date: 24/01/2003
32 32
33 This file implements a random data pool based on the use of an external 33 This file implements a random data pool based on the use of an external
34 entropy function. It is based on the ideas advocated by Peter Gutmann in 34 entropy function. It is based on the ideas advocated by Peter Gutmann in
35 his work on pseudo random sequence generators. It is not a 'paranoid' 35 his work on pseudo random sequence generators. It is not a 'paranoid'
36 random sequence generator and no attempt is made to protect the pool 36 random sequence generator and no attempt is made to protect the pool
37 from prying eyes either by memory locking or by techniques to obscure 37 from prying eyes either by memory locking or by techniques to obscure
38 its location in memory. 38 its location in memory.
39*/ 39*/
40 40
41#include <memory.h> 41#include <memory.h>
42#include "prng.h" 42#include "prng.h"
43 43
44/* mix a random data pool using the SHA1 compression function (as */ 44/* mix a random data pool using the SHA1 compression function (as */
45/* suggested by Peter Gutmann in his paper on random pools) */ 45/* suggested by Peter Gutmann in his paper on random pools) */
46 46
47static void prng_mix(unsigned char buf[]) 47static void prng_mix(unsigned char buf[])
48{ unsigned int i, len; 48{ unsigned int i, len;
49 sha1_ctx ctx[1]; 49 sha1_ctx ctx[1];
50 50
51 /*lint -e{663} unusual array to pointer conversion */ 51 /*lint -e{663} unusual array to pointer conversion */
52 for(i = 0; i < PRNG_POOL_SIZE; i += SHA1_DIGEST_SIZE) 52 for(i = 0; i < PRNG_POOL_SIZE; i += SHA1_DIGEST_SIZE)
53 { 53 {
54 /* copy digest size pool block into SHA1 hash block */ 54 /* copy digest size pool block into SHA1 hash block */
55 memcpy(ctx->hash, buf + (i ? i : PRNG_POOL_SIZE) 55 memcpy(ctx->hash, buf + (i ? i : PRNG_POOL_SIZE)
56 - SHA1_DIGEST_SIZE, SHA1_DIGEST_SIZE); 56 - SHA1_DIGEST_SIZE, SHA1_DIGEST_SIZE);
57 57
58 /* copy data from pool into the SHA1 data buffer */ 58 /* copy data from pool into the SHA1 data buffer */
59 len = PRNG_POOL_SIZE - i; 59 len = PRNG_POOL_SIZE - i;
60 memcpy(ctx->wbuf, buf + i, (len > SHA1_BLOCK_SIZE ? SHA1_BLOCK_SIZE : len)); 60 memcpy(ctx->wbuf, buf + i, (len > SHA1_BLOCK_SIZE ? SHA1_BLOCK_SIZE : len));
61 61
62 if(len < SHA1_BLOCK_SIZE) 62 if(len < SHA1_BLOCK_SIZE)
63 memcpy(((char*)ctx->wbuf) + len, buf, SHA1_BLOCK_SIZE - len); 63 memcpy(((char*)ctx->wbuf) + len, buf, SHA1_BLOCK_SIZE - len);
64 64
65 /* compress using the SHA1 compression function */ 65 /* compress using the SHA1 compression function */
66 sha1_compile(ctx); 66 sha1_compile(ctx);
67 67
68 /* put digest size block back into the random pool */ 68 /* put digest size block back into the random pool */
69 memcpy(buf + i, ctx->hash, SHA1_DIGEST_SIZE); 69 memcpy(buf + i, ctx->hash, SHA1_DIGEST_SIZE);
70 } 70 }
71} 71}
72 72
73/* refresh the output buffer and update the random pool by adding */ 73/* refresh the output buffer and update the random pool by adding */
74/* entropy and remixing */ 74/* entropy and remixing */
75 75
76static void update_pool(prng_ctx ctx[1]) 76static void update_pool(prng_ctx ctx[1])
77{ unsigned int i = 0; 77{ unsigned int i = 0;
78 78
79 /* transfer random pool data to the output buffer */ 79 /* transfer random pool data to the output buffer */
80 memcpy(ctx->obuf, ctx->rbuf, PRNG_POOL_SIZE); 80 memcpy(ctx->obuf, ctx->rbuf, PRNG_POOL_SIZE);
81 81
82 /* enter entropy data into the pool */ 82 /* enter entropy data into the pool */
83 while(i < PRNG_POOL_SIZE) 83 while(i < PRNG_POOL_SIZE)
84 i += ctx->entropy(ctx->rbuf + i, PRNG_POOL_SIZE - i); 84 i += ctx->entropy(ctx->rbuf + i, PRNG_POOL_SIZE - i);
85 85
86 /* invert and xor the original pool data into the pool */ 86 /* invert and xor the original pool data into the pool */
87 for(i = 0; i < PRNG_POOL_SIZE; ++i) 87 for(i = 0; i < PRNG_POOL_SIZE; ++i)
88 ctx->rbuf[i] ^= ~ctx->obuf[i]; 88 ctx->rbuf[i] ^= ~ctx->obuf[i];
89 89
90 /* mix the pool and the output buffer */ 90 /* mix the pool and the output buffer */
91 prng_mix(ctx->rbuf); 91 prng_mix(ctx->rbuf);
92 prng_mix(ctx->obuf); 92 prng_mix(ctx->obuf);
93} 93}
94 94
95void prng_init(prng_entropy_fn fun, prng_ctx ctx[1]) 95void prng_init(prng_entropy_fn fun, prng_ctx ctx[1])
96{ int i; 96{ int i;
97 97
98 /* clear the buffers and the counter in the context */ 98 /* clear the buffers and the counter in the context */
99 memset(ctx, 0, sizeof(prng_ctx)); 99 memset(ctx, 0, sizeof(prng_ctx));
100 100
101 /* set the pointer to the entropy collection function */ 101 /* set the pointer to the entropy collection function */
102 ctx->entropy = fun; 102 ctx->entropy = fun;
103 103
104 /* initialise the random data pool */ 104 /* initialise the random data pool */
105 update_pool(ctx); 105 update_pool(ctx);
106 106
107 /* mix the pool a minimum number of times */ 107 /* mix the pool a minimum number of times */
108 for(i = 0; i < PRNG_MIN_MIX; ++i) 108 for(i = 0; i < PRNG_MIN_MIX; ++i)
109 prng_mix(ctx->rbuf); 109 prng_mix(ctx->rbuf);
110 110
111 /* update the pool to prime the pool output buffer */ 111 /* update the pool to prime the pool output buffer */
112 update_pool(ctx); 112 update_pool(ctx);
113} 113}
114 114
115/* provide random bytes from the random data pool */ 115/* provide random bytes from the random data pool */
116 116
117void prng_rand(unsigned char data[], unsigned int data_len, prng_ctx ctx[1]) 117void prng_rand(unsigned char data[], unsigned int data_len, prng_ctx ctx[1])
118{ unsigned char *rp = data; 118{ unsigned char *rp = data;
119 unsigned int len, pos = ctx->pos; 119 unsigned int len, pos = ctx->pos;
120 120
121 while(data_len) 121 while(data_len)
122 { 122 {
123 /* transfer 'data_len' bytes (or the number of bytes remaining */ 123 /* transfer 'data_len' bytes (or the number of bytes remaining */
124 /* the pool output buffer if less) into the output */ 124 /* the pool output buffer if less) into the output */
125 len = (data_len < PRNG_POOL_SIZE - pos ? data_len : PRNG_POOL_SIZE - pos); 125 len = (data_len < PRNG_POOL_SIZE - pos ? data_len : PRNG_POOL_SIZE - pos);
126 memcpy(rp, ctx->obuf + pos, len); 126 memcpy(rp, ctx->obuf + pos, len);
127 rp += len; /* update ouput buffer position pointer */ 127 rp += len; /* update ouput buffer position pointer */
128 pos += len; /* update pool output buffer pointer */ 128 pos += len; /* update pool output buffer pointer */
129 data_len -= len; /* update the remaining data count */ 129 data_len -= len; /* update the remaining data count */
130 130
131 /* refresh the random pool if necessary */ 131 /* refresh the random pool if necessary */
132 if(pos == PRNG_POOL_SIZE) 132 if(pos == PRNG_POOL_SIZE)
133 { 133 {
134 update_pool(ctx); pos = 0; 134 update_pool(ctx); pos = 0;
135 } 135 }
136 } 136 }
137 137
138 ctx->pos = pos; 138 ctx->pos = pos;
139} 139}
140 140
141void prng_end(prng_ctx ctx[1]) 141void prng_end(prng_ctx ctx[1])
142{ 142{
143 /* ensure the data in the context is destroyed */ 143 /* ensure the data in the context is destroyed */
144 memset(ctx, 0, sizeof(prng_ctx)); 144 memset(ctx, 0, sizeof(prng_ctx));
145} 145}
146 146
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