1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
2  * All rights reserved.
3  *
4  * This package is an SSL implementation written
5  * by Eric Young (eay@cryptsoft.com).
6  * The implementation was written so as to conform with Netscapes SSL.
7  *
8  * This library is free for commercial and non-commercial use as long as
9  * the following conditions are aheared to.  The following conditions
10  * apply to all code found in this distribution, be it the RC4, RSA,
11  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
12  * included with this distribution is covered by the same copyright terms
13  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
14  *
15  * Copyright remains Eric Young's, and as such any Copyright notices in
16  * the code are not to be removed.
17  * If this package is used in a product, Eric Young should be given attribution
18  * as the author of the parts of the library used.
19  * This can be in the form of a textual message at program startup or
20  * in documentation (online or textual) provided with the package.
21  *
22  * Redistribution and use in source and binary forms, with or without
23  * modification, are permitted provided that the following conditions
24  * are met:
25  * 1. Redistributions of source code must retain the copyright
26  *    notice, this list of conditions and the following disclaimer.
27  * 2. Redistributions in binary form must reproduce the above copyright
28  *    notice, this list of conditions and the following disclaimer in the
29  *    documentation and/or other materials provided with the distribution.
30  * 3. All advertising materials mentioning features or use of this software
31  *    must display the following acknowledgement:
32  *    "This product includes cryptographic software written by
33  *     Eric Young (eay@cryptsoft.com)"
34  *    The word 'cryptographic' can be left out if the rouines from the library
35  *    being used are not cryptographic related :-).
36  * 4. If you include any Windows specific code (or a derivative thereof) from
37  *    the apps directory (application code) you must include an acknowledgement:
38  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
39  *
40  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
50  * SUCH DAMAGE.
51  *
52  * The licence and distribution terms for any publically available version or
53  * derivative of this code cannot be changed.  i.e. this code cannot simply be
54  * copied and put under another distribution licence
55  * [including the GNU Public Licence.] */
56 
57 #include <openssl/asn1.h>
58 
59 #include <string.h>
60 
61 #include <openssl/err.h>
62 #include <openssl/mem.h>
63 
64 
ASN1_BIT_STRING_set(ASN1_BIT_STRING * x,unsigned char * d,int len)65 int ASN1_BIT_STRING_set(ASN1_BIT_STRING *x, unsigned char *d, int len)
66 { return M_ASN1_BIT_STRING_set(x, d, len); }
67 
i2c_ASN1_BIT_STRING(ASN1_BIT_STRING * a,unsigned char ** pp)68 int i2c_ASN1_BIT_STRING(ASN1_BIT_STRING *a, unsigned char **pp)
69 	{
70 	int ret,j,bits,len;
71 	unsigned char *p,*d;
72 
73 	if (a == NULL) return(0);
74 
75 	len=a->length;
76 
77 	if (len > 0)
78 		{
79 		if (a->flags & ASN1_STRING_FLAG_BITS_LEFT)
80 			{
81 			bits=(int)a->flags&0x07;
82 			}
83 		else
84 			{
85 			for ( ; len > 0; len--)
86 				{
87 				if (a->data[len-1]) break;
88 				}
89 			j=a->data[len-1];
90 			if      (j & 0x01) bits=0;
91 			else if (j & 0x02) bits=1;
92 			else if (j & 0x04) bits=2;
93 			else if (j & 0x08) bits=3;
94 			else if (j & 0x10) bits=4;
95 			else if (j & 0x20) bits=5;
96 			else if (j & 0x40) bits=6;
97 			else if (j & 0x80) bits=7;
98 			else bits=0; /* should not happen */
99 			}
100 		}
101 	else
102 		bits=0;
103 
104 	ret=1+len;
105 	if (pp == NULL) return(ret);
106 
107 	p= *pp;
108 
109 	*(p++)=(unsigned char)bits;
110 	d=a->data;
111 	memcpy(p,d,len);
112 	p+=len;
113 	if (len > 0) p[-1]&=(0xff<<bits);
114 	*pp=p;
115 	return(ret);
116 	}
117 
c2i_ASN1_BIT_STRING(ASN1_BIT_STRING ** a,const unsigned char ** pp,long len)118 ASN1_BIT_STRING *c2i_ASN1_BIT_STRING(ASN1_BIT_STRING **a,
119 	const unsigned char **pp, long len)
120 	{
121 	ASN1_BIT_STRING *ret=NULL;
122 	const unsigned char *p;
123 	unsigned char *s;
124 	int padding;
125 
126 	if (len < 1)
127 		{
128 		OPENSSL_PUT_ERROR(ASN1, c2i_ASN1_BIT_STRING,
129 			ASN1_R_STRING_TOO_SHORT);
130 		goto err;
131 		}
132 
133 	if ((a == NULL) || ((*a) == NULL))
134 		{
135 		if ((ret=M_ASN1_BIT_STRING_new()) == NULL) return(NULL);
136 		}
137 	else
138 		ret=(*a);
139 
140 	p= *pp;
141 	padding = *(p++);
142 	if (padding > 7)
143 		{
144 		OPENSSL_PUT_ERROR(ASN1, c2i_ASN1_BIT_STRING,
145 			ASN1_R_INVALID_BIT_STRING_BITS_LEFT);
146 		goto err;
147 		}
148 
149 	/* We do this to preserve the settings.  If we modify
150 	 * the settings, via the _set_bit function, we will recalculate
151 	 * on output */
152 	ret->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear */
153 	ret->flags|=(ASN1_STRING_FLAG_BITS_LEFT|padding); /* set */
154 
155 	if (len-- > 1) /* using one because of the bits left byte */
156 		{
157 		s=(unsigned char *)OPENSSL_malloc((int)len);
158 		if (s == NULL)
159 			{
160 			OPENSSL_PUT_ERROR(ASN1, c2i_ASN1_BIT_STRING,
161 				ERR_R_MALLOC_FAILURE);
162 			goto err;
163 			}
164 		memcpy(s,p,(int)len);
165 		s[len-1]&=(0xff<<padding);
166 		p+=len;
167 		}
168 	else
169 		s=NULL;
170 
171 	ret->length=(int)len;
172 	if (ret->data != NULL) OPENSSL_free(ret->data);
173 	ret->data=s;
174 	ret->type=V_ASN1_BIT_STRING;
175 	if (a != NULL) (*a)=ret;
176 	*pp=p;
177 	return(ret);
178 err:
179 	if ((ret != NULL) && ((a == NULL) || (*a != ret)))
180 		M_ASN1_BIT_STRING_free(ret);
181 	return(NULL);
182 	}
183 
184 /* These next 2 functions from Goetz Babin-Ebell <babinebell@trustcenter.de>
185  */
ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING * a,int n,int value)186 int ASN1_BIT_STRING_set_bit(ASN1_BIT_STRING *a, int n, int value)
187 	{
188 	int w,v,iv;
189 	unsigned char *c;
190 
191 	w=n/8;
192 	v=1<<(7-(n&0x07));
193 	iv= ~v;
194 	if (!value) v=0;
195 
196 	if (a == NULL)
197 		return 0;
198 
199 	a->flags&= ~(ASN1_STRING_FLAG_BITS_LEFT|0x07); /* clear, set on write */
200 
201 	if ((a->length < (w+1)) || (a->data == NULL))
202 		{
203 		if (!value) return(1); /* Don't need to set */
204 		if (a->data == NULL)
205 			c=(unsigned char *)OPENSSL_malloc(w+1);
206 		else
207 			c=(unsigned char *)OPENSSL_realloc_clean(a->data,
208 								 a->length,
209 								 w+1);
210 		if (c == NULL)
211 			{
212 			OPENSSL_PUT_ERROR(ASN1, ASN1_BIT_STRING_set_bit, ERR_R_MALLOC_FAILURE);
213 			return 0;
214 			}
215   		if (w+1-a->length > 0) memset(c+a->length, 0, w+1-a->length);
216 		a->data=c;
217 		a->length=w+1;
218 	}
219 	a->data[w]=((a->data[w])&iv)|v;
220 	while ((a->length > 0) && (a->data[a->length-1] == 0))
221 		a->length--;
222 	return(1);
223 	}
224 
ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING * a,int n)225 int ASN1_BIT_STRING_get_bit(ASN1_BIT_STRING *a, int n)
226 	{
227 	int w,v;
228 
229 	w=n/8;
230 	v=1<<(7-(n&0x07));
231 	if ((a == NULL) || (a->length < (w+1)) || (a->data == NULL))
232 		return(0);
233 	return((a->data[w]&v) != 0);
234 	}
235 
236 /*
237  * Checks if the given bit string contains only bits specified by
238  * the flags vector. Returns 0 if there is at least one bit set in 'a'
239  * which is not specified in 'flags', 1 otherwise.
240  * 'len' is the length of 'flags'.
241  */
ASN1_BIT_STRING_check(ASN1_BIT_STRING * a,unsigned char * flags,int flags_len)242 int ASN1_BIT_STRING_check(ASN1_BIT_STRING *a,
243 			  unsigned char *flags, int flags_len)
244 	{
245 	int i, ok;
246 	/* Check if there is one bit set at all. */
247 	if (!a || !a->data) return 1;
248 
249 	/* Check each byte of the internal representation of the bit string. */
250 	ok = 1;
251 	for (i = 0; i < a->length && ok; ++i)
252 		{
253 		unsigned char mask = i < flags_len ? ~flags[i] : 0xff;
254 		/* We are done if there is an unneeded bit set. */
255 		ok = (a->data[i] & mask) == 0;
256 		}
257 	return ok;
258 	}
259