]>
Commit | Line | Data |
---|---|---|
9b141126 UM |
1 | /* crypto/bn/bn_ctx.c */ |
2 | /* Written by Ulf Moeller for the OpenSSL project. */ | |
3 | /* ==================================================================== | |
4 | * Copyright (c) 1998-2000 The OpenSSL Project. All rights reserved. | |
5 | * | |
6 | * Redistribution and use in source and binary forms, with or without | |
7 | * modification, are permitted provided that the following conditions | |
8 | * are met: | |
9 | * | |
10 | * 1. Redistributions of source code must retain the above copyright | |
11 | * notice, this list of conditions and the following disclaimer. | |
12 | * | |
13 | * 2. Redistributions in binary form must reproduce the above copyright | |
14 | * notice, this list of conditions and the following disclaimer in | |
15 | * the documentation and/or other materials provided with the | |
16 | * distribution. | |
17 | * | |
18 | * 3. All advertising materials mentioning features or use of this | |
19 | * software must display the following acknowledgment: | |
20 | * "This product includes software developed by the OpenSSL Project | |
21 | * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" | |
22 | * | |
23 | * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to | |
24 | * endorse or promote products derived from this software without | |
25 | * prior written permission. For written permission, please contact | |
26 | * openssl-core@openssl.org. | |
27 | * | |
28 | * 5. Products derived from this software may not be called "OpenSSL" | |
29 | * nor may "OpenSSL" appear in their names without prior written | |
30 | * permission of the OpenSSL Project. | |
31 | * | |
32 | * 6. Redistributions of any form whatsoever must retain the following | |
33 | * acknowledgment: | |
34 | * "This product includes software developed by the OpenSSL Project | |
35 | * for use in the OpenSSL Toolkit (http://www.openssl.org/)" | |
36 | * | |
37 | * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY | |
38 | * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
39 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
40 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR | |
41 | * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | |
42 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
43 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; | |
44 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
45 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, | |
46 | * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
47 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED | |
48 | * OF THE POSSIBILITY OF SUCH DAMAGE. | |
49 | * ==================================================================== | |
50 | * | |
51 | * This product includes cryptographic software written by Eric Young | |
52 | * (eay@cryptsoft.com). This product includes software written by Tim | |
53 | * Hudson (tjh@cryptsoft.com). | |
54 | * | |
55 | */ | |
56 | ||
37e48b88 BM |
57 | #ifndef BN_CTX_DEBUG |
58 | # undef NDEBUG /* avoid conflicting definitions */ | |
59 | # define NDEBUG | |
60 | #endif | |
61 | ||
9b141126 UM |
62 | #include <stdio.h> |
63 | #include <assert.h> | |
64 | #include "cryptlib.h" | |
65 | #include <openssl/bn.h> | |
66 | ||
67 | ||
68 | BN_CTX *BN_CTX_new(void) | |
69 | { | |
70 | BN_CTX *ret; | |
71 | ||
26a3a48d | 72 | ret=(BN_CTX *)OPENSSL_malloc(sizeof(BN_CTX)); |
9b141126 UM |
73 | if (ret == NULL) |
74 | { | |
75 | BNerr(BN_F_BN_CTX_NEW,ERR_R_MALLOC_FAILURE); | |
76 | return(NULL); | |
77 | } | |
78 | ||
79 | BN_CTX_init(ret); | |
80 | ret->flags=BN_FLG_MALLOCED; | |
81 | return(ret); | |
82 | } | |
83 | ||
84 | void BN_CTX_init(BN_CTX *ctx) | |
85 | { | |
86 | int i; | |
87 | ctx->tos = 0; | |
88 | ctx->flags = 0; | |
89 | ctx->depth = 0; | |
eb5a6a55 | 90 | ctx->too_many = 0; |
9b141126 UM |
91 | for (i = 0; i < BN_CTX_NUM; i++) |
92 | BN_init(&(ctx->bn[i])); | |
93 | } | |
94 | ||
95 | void BN_CTX_free(BN_CTX *ctx) | |
96 | { | |
97 | int i; | |
98 | ||
99 | if (ctx == NULL) return; | |
100 | assert(ctx->depth == 0); | |
101 | ||
102 | for (i=0; i < BN_CTX_NUM; i++) | |
103 | BN_clear_free(&(ctx->bn[i])); | |
104 | if (ctx->flags & BN_FLG_MALLOCED) | |
26a3a48d | 105 | OPENSSL_free(ctx); |
9b141126 UM |
106 | } |
107 | ||
108 | void BN_CTX_start(BN_CTX *ctx) | |
109 | { | |
37e48b88 BM |
110 | if (ctx->depth < BN_CTX_NUM_POS) |
111 | ctx->pos[ctx->depth] = ctx->tos; | |
112 | ctx->depth++; | |
9b141126 UM |
113 | } |
114 | ||
7f7b8d68 | 115 | |
9b141126 UM |
116 | BIGNUM *BN_CTX_get(BN_CTX *ctx) |
117 | { | |
7f7b8d68 BM |
118 | /* Note: If BN_CTX_get is ever changed to allocate BIGNUMs dynamically, |
119 | * make sure that if BN_CTX_get fails once it will return NULL again | |
120 | * until BN_CTX_end is called. (This is so that callers have to check | |
121 | * only the last return value.) | |
122 | */ | |
37e48b88 | 123 | if (ctx->depth > BN_CTX_NUM_POS || ctx->tos >= BN_CTX_NUM) |
9b141126 | 124 | { |
37e48b88 BM |
125 | if (!ctx->too_many) |
126 | { | |
127 | BNerr(BN_F_BN_CTX_GET,BN_R_TOO_MANY_TEMPORARY_VARIABLES); | |
cae55bfc | 128 | /* disable error code until BN_CTX_end is called: */ |
37e48b88 BM |
129 | ctx->too_many = 1; |
130 | } | |
9b141126 UM |
131 | return NULL; |
132 | } | |
133 | return (&(ctx->bn[ctx->tos++])); | |
134 | } | |
135 | ||
136 | void BN_CTX_end(BN_CTX *ctx) | |
137 | { | |
138 | if (ctx == NULL) return; | |
139 | assert(ctx->depth > 0); | |
37e48b88 BM |
140 | if (ctx->depth == 0) |
141 | /* should never happen, but we can tolerate it if not in | |
142 | * debug mode (could be a 'goto err' in the calling function | |
143 | * before BN_CTX_start was reached) */ | |
144 | BN_CTX_start(ctx); | |
145 | ||
146 | ctx->too_many = 0; | |
9b141126 | 147 | ctx->depth--; |
37e48b88 BM |
148 | if (ctx->depth < BN_CTX_NUM_POS) |
149 | ctx->tos = ctx->pos[ctx->depth]; | |
9b141126 | 150 | } |