1 /* $NetBSD: rand-w32.c,v 1.1.1.2 2014/04/24 12:45:30 pettai Exp $ */
2
3 /*
4 * Copyright (c) 2006 Kungliga Tekniska Högskolan
5 * (Royal Institute of Technology, Stockholm, Sweden).
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * 3. Neither the name of the Institute nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <config.h>
37 #include <krb5/roken.h>
38
39 #include <wincrypt.h>
40
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <rand.h>
44 #include <heim_threads.h>
45
46 #include "randi.h"
47
48 volatile static HCRYPTPROV g_cryptprovider = 0;
49
50 static HCRYPTPROV
_hc_CryptProvider(void)51 _hc_CryptProvider(void)
52 {
53 BOOL rv;
54 HCRYPTPROV cryptprovider = 0;
55
56 if (g_cryptprovider != 0)
57 return g_cryptprovider;
58
59 rv = CryptAcquireContext(&cryptprovider, NULL,
60 MS_ENHANCED_PROV, PROV_RSA_FULL,
61 CRYPT_VERIFYCONTEXT);
62
63 if (GetLastError() == NTE_BAD_KEYSET) {
64 rv = CryptAcquireContext(&cryptprovider, NULL,
65 MS_ENHANCED_PROV, PROV_RSA_FULL,
66 CRYPT_NEWKEYSET);
67 }
68
69 if (rv) {
70 /* try the default provider */
71 rv = CryptAcquireContext(&cryptprovider, NULL, 0, PROV_RSA_FULL,
72 CRYPT_VERIFYCONTEXT);
73
74 if (GetLastError() == NTE_BAD_KEYSET) {
75 rv = CryptAcquireContext(&cryptprovider, NULL,
76 MS_ENHANCED_PROV, PROV_RSA_FULL,
77 CRYPT_NEWKEYSET);
78 }
79 }
80
81 if (rv) {
82 /* try just a default random number generator */
83 rv = CryptAcquireContext(&cryptprovider, NULL, 0, PROV_RNG,
84 CRYPT_VERIFYCONTEXT);
85 }
86
87 if (rv &&
88 InterlockedCompareExchangePointer((PVOID *) &g_cryptprovider,
89 (PVOID) cryptprovider, 0) != 0) {
90
91 CryptReleaseContext(cryptprovider, 0);
92 cryptprovider = g_cryptprovider;
93 }
94
95 return cryptprovider;
96 }
97
98 /*
99 *
100 */
101
102
103 static void
w32crypto_seed(const void * indata,int size)104 w32crypto_seed(const void *indata, int size)
105 {
106 }
107
108
109 static int
w32crypto_bytes(unsigned char * outdata,int size)110 w32crypto_bytes(unsigned char *outdata, int size)
111 {
112 if (CryptGenRandom(_hc_CryptProvider(), size, outdata))
113 return 1;
114 return 0;
115 }
116
117 static void
w32crypto_cleanup(void)118 w32crypto_cleanup(void)
119 {
120 HCRYPTPROV cryptprovider;
121
122 if (InterlockedCompareExchangePointer((PVOID *) &cryptprovider,
123 0, (PVOID) g_cryptprovider) == 0) {
124 CryptReleaseContext(cryptprovider, 0);
125 }
126 }
127
128 static void
w32crypto_add(const void * indata,int size,double entropi)129 w32crypto_add(const void *indata, int size, double entropi)
130 {
131 }
132
133 static int
w32crypto_status(void)134 w32crypto_status(void)
135 {
136 if (_hc_CryptProvider() == 0)
137 return 0;
138 return 1;
139 }
140
141 const RAND_METHOD hc_rand_w32crypto_method = {
142 w32crypto_seed,
143 w32crypto_bytes,
144 w32crypto_cleanup,
145 w32crypto_add,
146 w32crypto_bytes,
147 w32crypto_status
148 };
149
150 const RAND_METHOD *
RAND_w32crypto_method(void)151 RAND_w32crypto_method(void)
152 {
153 return &hc_rand_w32crypto_method;
154 }
155