1 /* crypto/asn1/a_bitstr.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to. The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 * notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 * notice, this list of conditions and the following disclaimer in the
30 * documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 * must display the following acknowledgement:
33 * "This product includes cryptographic software written by
34 * Eric Young (eay@cryptsoft.com)"
35 * The word 'cryptographic' can be left out if the rouines from the library
36 * being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 * the apps directory (application code) you must include an acknowledgement:
39 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed. i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59 #include <stdio.h>
60 #include "cryptlib.h"
61 #include <openssl/asn1.h>
62
63 int ASN1_BIT_STRING_set(ASN1_BIT_STRING *x, unsigned char *d, int len)
64 { return M_ASN1_BIT_STRING_set(x, d, len); }
65
66 int i2c_ASN1_BIT_STRING(ASN1_BIT_STRING *a, unsigned char **pp)
67 {
68 int ret,j,bits,len;
69 unsigned char *p,*d;
70
71 if (a == NULL) return(0);
72
73 len=a->length;
74
75 if (len > 0)
76 {
77 if (a->flags & ASN1_STRING_FLAG_BITS_LEFT)
78 {
79 bits=(int)a->flags&0x07;
80 }
81 else
82 {
83 for ( ; len > 0; len--)
84 {
85 if (a->data[len-1]) break;
86 }
87 j=a->data[len-1];
88 if (j & 0x01) bits=0;
89 else if (j & 0x02) bits=1;
90 else if (j & 0x04) bits=2;
91 else if (j & 0x08) bits=3;
92 else if (j & 0x10) bits=4;
93 else if (j & 0x20) bits=5;
94 else if (j & 0x40) bits=6;
95 else if (j & 0x80) bits=7;
96 else bits=0; /* should not happen */
97 }
98 }
99 else
100 bits=0;
101
102 ret=1+len;
103 if (pp == NULL) return(ret);
104
105 p= *pp;
106
107 *(p++)=(unsigned char)bits;
108 d=a->data;
109 memcpy(p,d,len);
110 p+=len;
111 if (len > 0) p[-1]&=(0xff<<bits);
112 *pp=p;
113 return(ret);
114 }
115
116 ASN1_BIT_STRING *c2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a,
117 const unsigned char **pp, long len)
118 {
119 ASN1_BIT_STRING *ret=NULL;
120 const unsigned char *p;
121 unsigned char *s;
122 int i;
123
124 if (len < 1)
125 {
126 i=ASN1_R_STRING_TOO_SHORT;
127 goto err;
128 }
129
130 if ((a == NULL) || ((*a) == NULL))
131 {
132 if ((ret=M_ASN1_BIT_STRING_new()) == NULL) return(NULL);
133 }
134 else
135 ret=(*a);
136
137 p= *pp;
138 i= *(p++);
139 /* We do this to preserve the settings. If we modify
140 * the settings, via the _set_bit function, we will recalculate
141 * on output */
142 ret->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear */
143 ret->flags|=(ASN1_STRING_FLAG_BITS_LEFT|(i&0x07)); /* set */
144
145 if (len-- > 1) /* using one because of the bits left byte */
146 {
147 s=(unsigned char *)OPENSSL_malloc((int)len);
148 if (s == NULL)
149 {
150 i=ERR_R_MALLOC_FAILURE;
151 goto err;
152 }
153 memcpy(s,p,(int)len);
154 s[len-1]&=(0xff<<i);
155 p+=len;
156 }
157 else
158 s=NULL;
159
160 ret->length=(int)len;
161 if (ret->data != NULL) OPENSSL_free(ret->data);
162 ret->data=s;
163 ret->type=V_ASN1_BIT_STRING;
164 if (a != NULL) (*a)=ret;
165 *pp=p;
166 return(ret);
167 err:
168 ASN1err(ASN1_F_C2I_ASN1_BIT_STRING,i);
169 if ((ret != NULL) && ((a == NULL) || (*a != ret)))
170 M_ASN1_BIT_STRING_free(ret);
171 return(NULL);
172 }
173
174 /* These next 2 functions from Goetz Babin-Ebell <babinebell@trustcenter.de>
175 */
176 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value)
177 {
178 int w,v,iv;
179 unsigned char *c;
180
181 w=n/8;
182 v=1<<(7-(n&0x07));
183 iv= ~v;
184 if (!value) v=0;
185
186 if (a == NULL)
187 return 0;
188
189 a->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear, set on write */
190
191 if ((a->length < (w+1)) || (a->data == NULL))
192 {
193 if (!value) return(1); /* Don't need to set */
194 if (a->data == NULL)
195 c=(unsigned char *)OPENSSL_malloc(w+1);
196 else
197 c=(unsigned char *)OPENSSL_realloc_clean(a->data,
198 a->length,
199 w+1);
200 if (c == NULL)
201 {
202 ASN1err(ASN1_F_ASN1_BIT_STRING_SET_BIT,ERR_R_MALLOC_FAILURE);
203 return 0;
204 }
205 if (w+1-a->length > 0) memset(c+a->length, 0, w+1-a->length);
206 a->data=c;
207 a->length=w+1;
208 }
209 a->data[w]=((a->data[w])&iv)|v;
210 while ((a->length > 0) && (a->data[a->length-1] == 0))
211 a->length--;
212 return(1);
213 }
214
215 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n)
216 {
217 int w,v;
218
219 w=n/8;
220 v=1<<(7-(n&0x07));
221 if ((a == NULL) || (a->length < (w+1)) || (a->data == NULL))
222 return(0);
223 return((a->data[w]&v) != 0);
224 }
225
226 /*
227 * Checks if the given bit string contains only bits specified by
228 * the flags vector. Returns 0 if there is at least one bit set in 'a'
229 * which is not specified in 'flags', 1 otherwise.
230 * 'len' is the length of 'flags'.
231 */
232 int ASN1_BIT_STRING_check(ASN1_BIT_STRING *a,
233 unsigned char *flags, int flags_len)
234 {
235 int i, ok;
236 /* Check if there is one bit set at all. */
237 if (!a || !a->data) return 1;
238
239 /* Check each byte of the internal representation of the bit string. */
240 ok = 1;
241 for (i = 0; i < a->length && ok; ++i)
242 {
243 unsigned char mask = i < flags_len ? ~flags[i] : 0xff;
244 /* We are done if there is an unneeded bit set. */
245 ok = (a->data[i] & mask) == 0;
246 }
247 return ok;
248 }