1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
|
/* $OpenBSD: prf.c,v 1.14 2004/05/23 18:17:56 hshoexer Exp $ */
/* $EOM: prf.c,v 1.7 1999/05/02 12:50:29 niklas Exp $ */
/*
* Copyright (c) 1998 Niels Provos. All rights reserved.
* Copyright (c) 1999 Niklas Hallqvist. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This code was written under funding by Ericsson Radio Systems.
*/
#include <sys/param.h>
#include <stdlib.h>
#include <string.h>
#include "sysdep.h"
#include "hash.h"
#include "log.h"
#include "prf.h"
void prf_hash_init(struct prf_hash_ctx *);
void prf_hash_update(struct prf_hash_ctx *, unsigned char *, unsigned int);
void prf_hash_final(unsigned char *, struct prf_hash_ctx *);
/* PRF behaves likes a hash */
void
prf_hash_init(struct prf_hash_ctx *ctx)
{
memcpy(ctx->hash->ctx, ctx->ctx, ctx->hash->ctxsize);
memcpy(ctx->hash->ctx2, ctx->ctx2, ctx->hash->ctxsize);
}
void
prf_hash_update(struct prf_hash_ctx *ctx, unsigned char *data,
unsigned int len)
{
ctx->hash->Update(ctx->hash->ctx, data, len);
}
void
prf_hash_final(unsigned char *digest, struct prf_hash_ctx *ctx)
{
ctx->hash->HMACFinal(digest, ctx->hash);
}
/*
* Obtain a Pseudo-Random Function for us. At the moment this is
* the HMAC version of a hash. See RFC-2104 for reference.
*/
struct prf *
prf_alloc(enum prfs type, int subtype, unsigned char *shared,
unsigned int sharedsize)
{
struct hash *hash;
struct prf *prf;
struct prf_hash_ctx *prfctx;
switch (type) {
case PRF_HMAC:
hash = hash_get(subtype);
if (!hash) {
log_print("prf_alloc: unknown hash type %d", subtype);
return 0;
}
break;
default:
log_print("prf_alloc: unknown PRF type %d", type);
return 0;
}
prf = malloc(sizeof *prf);
if (!prf) {
log_error("prf_alloc: malloc (%lu) failed",
(unsigned long)sizeof *prf);
return 0;
}
if (type == PRF_HMAC) {
/* Obtain needed memory. */
prfctx = malloc(sizeof *prfctx);
if (!prfctx) {
log_error("prf_alloc: malloc (%lu) failed",
(unsigned long)sizeof *prfctx);
goto cleanprf;
}
prf->prfctx = prfctx;
prfctx->ctx = malloc(hash->ctxsize);
if (!prfctx->ctx) {
log_error("prf_alloc: malloc (%d) failed",
hash->ctxsize);
goto cleanprfctx;
}
prfctx->ctx2 = malloc(hash->ctxsize);
if (!prfctx->ctx2) {
log_error("prf_alloc: malloc (%d) failed",
hash->ctxsize);
free(prfctx->ctx);
goto cleanprfctx;
}
prf->type = PRF_HMAC;
prf->blocksize = hash->hashsize;
prfctx->hash = hash;
/* Use the correct function pointers. */
prf->Init = (void(*)(void *))prf_hash_init;
prf->Update = (void(*)(void *, unsigned char *,
unsigned int))prf_hash_update;
prf->Final = (void(*)(unsigned char *, void *))prf_hash_final;
/* Init HMAC contexts. */
hash->HMACInit(hash, shared, sharedsize);
/* Save contexts. */
memcpy(prfctx->ctx, hash->ctx, hash->ctxsize);
memcpy(prfctx->ctx2, hash->ctx2, hash->ctxsize);
}
return prf;
cleanprfctx:
free(prf->prfctx);
cleanprf:
free(prf);
return 0;
}
/* Deallocate the PRF pointed to by PRF. */
void
prf_free(struct prf *prf)
{
struct prf_hash_ctx *prfctx = prf->prfctx;
if (prf->type == PRF_HMAC) {
free(prfctx->ctx2);
free(prfctx->ctx);
}
free(prf->prfctx);
free(prf);
}
|
