1 /* $OpenBSD: x_bignum.c,v 1.12 2022/07/30 13:42:25 jsing Exp $ */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3 * project 2000.
4 */
5 /* ====================================================================
6 * Copyright (c) 2000 The OpenSSL Project. 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
17 * the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24 *
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * licensing@OpenSSL.org.
29 *
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
33 *
34 * 6. Redistributions of any form whatsoever must retain the following
35 * acknowledgment:
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38 *
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
52 *
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
56 *
57 */
58
59 #include <stdio.h>
60
61 #include <openssl/asn1t.h>
62 #include <openssl/bn.h>
63
64 #include "asn1_locl.h"
65 #include "bytestring.h"
66
67 /*
68 * Custom primitive type for that reads an ASN.1 INTEGER into a BIGNUM.
69 */
70
71 static int bn_new(ASN1_VALUE **pval, const ASN1_ITEM *it);
72 static void bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it);
73 static void bn_clear(ASN1_VALUE **pval, const ASN1_ITEM *it);
74
75 static int bn_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype,
76 const ASN1_ITEM *it);
77 static int bn_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,
78 int utype, char *free_cont, const ASN1_ITEM *it);
79 static int bn_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it,
80 int indent, const ASN1_PCTX *pctx);
81
82 static ASN1_PRIMITIVE_FUNCS bignum_pf = {
83 .app_data = NULL,
84 .flags = 0,
85 .prim_new = bn_new,
86 .prim_free = bn_free,
87 .prim_clear = bn_clear,
88 .prim_c2i = bn_c2i,
89 .prim_i2c = bn_i2c,
90 .prim_print = bn_print,
91 };
92
93 const ASN1_ITEM BIGNUM_it = {
94 .itype = ASN1_ITYPE_PRIMITIVE,
95 .utype = V_ASN1_INTEGER,
96 .templates = NULL,
97 .tcount = 0,
98 .funcs = &bignum_pf,
99 .size = 0,
100 .sname = "BIGNUM",
101 };
102
103 const ASN1_ITEM CBIGNUM_it = {
104 .itype = ASN1_ITYPE_PRIMITIVE,
105 .utype = V_ASN1_INTEGER,
106 .templates = NULL,
107 .tcount = 0,
108 .funcs = &bignum_pf,
109 .size = 0,
110 .sname = "BIGNUM",
111 };
112
113 static int
bn_new(ASN1_VALUE ** pval,const ASN1_ITEM * it)114 bn_new(ASN1_VALUE **pval, const ASN1_ITEM *it)
115 {
116 if ((*pval = (ASN1_VALUE *)BN_new()) == NULL)
117 return 0;
118
119 return 1;
120 }
121
122 static void
bn_clear(ASN1_VALUE ** pval,const ASN1_ITEM * it)123 bn_clear(ASN1_VALUE **pval, const ASN1_ITEM *it)
124 {
125 BN_free((BIGNUM *)*pval);
126 *pval = NULL;
127 }
128
129 static void
bn_free(ASN1_VALUE ** pval,const ASN1_ITEM * it)130 bn_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
131 {
132 if (*pval == NULL)
133 return;
134
135 bn_clear(pval, it);
136 }
137
138 static int
bn_i2c(ASN1_VALUE ** pval,unsigned char * content,int * putype,const ASN1_ITEM * it)139 bn_i2c(ASN1_VALUE **pval, unsigned char *content, int *putype, const ASN1_ITEM *it)
140 {
141 ASN1_INTEGER *aint = NULL;
142 unsigned char **pp = NULL;
143 const BIGNUM *bn;
144 int ret;
145
146 if (*pval == NULL)
147 return -1;
148
149 bn = (const BIGNUM *)*pval;
150
151 if ((aint = BN_to_ASN1_INTEGER(bn, NULL)) == NULL)
152 return -1;
153
154 if (content != NULL)
155 pp = &content;
156
157 ret = i2c_ASN1_INTEGER(aint, pp);
158
159 ASN1_INTEGER_free(aint);
160
161 return ret;
162 }
163
164 static int
bn_c2i(ASN1_VALUE ** pval,const unsigned char * content,int len,int utype,char * free_content,const ASN1_ITEM * it)165 bn_c2i(ASN1_VALUE **pval, const unsigned char *content, int len, int utype,
166 char *free_content, const ASN1_ITEM *it)
167 {
168 ASN1_INTEGER *aint = NULL;
169 BIGNUM *bn;
170 CBS cbs;
171 int ret = 0;
172
173 bn_clear(pval, it);
174
175 if (len < 0)
176 goto err;
177 CBS_init(&cbs, content, len);
178 if (!c2i_ASN1_INTEGER_cbs(&aint, &cbs))
179 goto err;
180
181 if ((bn = ASN1_INTEGER_to_BN(aint, NULL)) == NULL)
182 goto err;
183 *pval = (ASN1_VALUE *)bn;
184
185 ret = 1;
186
187 err:
188 ASN1_INTEGER_free(aint);
189
190 return ret;
191 }
192
193 static int
bn_print(BIO * out,ASN1_VALUE ** pval,const ASN1_ITEM * it,int indent,const ASN1_PCTX * pctx)194 bn_print(BIO *out, ASN1_VALUE **pval, const ASN1_ITEM *it, int indent,
195 const ASN1_PCTX *pctx)
196 {
197 const BIGNUM *bn = (BIGNUM *)*pval;
198
199 if (!BN_print(out, bn))
200 return 0;
201 if (BIO_printf(out, "\n") <= 0)
202 return 0;
203
204 return 1;
205 }
206