xref: /openbsd-src/lib/libcrypto/asn1/asn1_lib.c (revision db3296cf5c1dd9058ceecc3a29fe4aaa0bd26000)
1 /* crypto/asn1/asn1_lib.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 <limits.h>
61 #include "cryptlib.h"
62 #include <openssl/asn1.h>
63 #include <openssl/asn1_mac.h>
64 
65 static int asn1_get_length(unsigned char **pp,int *inf,long *rl,int max);
66 static void asn1_put_length(unsigned char **pp, int length);
67 const char *ASN1_version="ASN.1" OPENSSL_VERSION_PTEXT;
68 
69 int ASN1_check_infinite_end(unsigned char **p, long len)
70 	{
71 	/* If there is 0 or 1 byte left, the length check should pick
72 	 * things up */
73 	if (len <= 0)
74 		return(1);
75 	else if ((len >= 2) && ((*p)[0] == 0) && ((*p)[1] == 0))
76 		{
77 		(*p)+=2;
78 		return(1);
79 		}
80 	return(0);
81 	}
82 
83 
84 int ASN1_get_object(unsigned char **pp, long *plength, int *ptag, int *pclass,
85 	     long omax)
86 	{
87 	int i,ret;
88 	long l;
89 	unsigned char *p= *pp;
90 	int tag,xclass,inf;
91 	long max=omax;
92 
93 	if (!max) goto err;
94 	ret=(*p&V_ASN1_CONSTRUCTED);
95 	xclass=(*p&V_ASN1_PRIVATE);
96 	i= *p&V_ASN1_PRIMITIVE_TAG;
97 	if (i == V_ASN1_PRIMITIVE_TAG)
98 		{		/* high-tag */
99 		p++;
100 		if (--max == 0) goto err;
101 		l=0;
102 		while (*p&0x80)
103 			{
104 			l<<=7L;
105 			l|= *(p++)&0x7f;
106 			if (--max == 0) goto err;
107 			}
108 		l<<=7L;
109 		l|= *(p++)&0x7f;
110 		tag=(int)l;
111 		}
112 	else
113 		{
114 		tag=i;
115 		p++;
116 		if (--max == 0) goto err;
117 		}
118 	*ptag=tag;
119 	*pclass=xclass;
120 	if (!asn1_get_length(&p,&inf,plength,(int)max)) goto err;
121 
122 #if 0
123 	fprintf(stderr,"p=%d + *plength=%ld > omax=%ld + *pp=%d  (%d > %d)\n",
124 		(int)p,*plength,omax,(int)*pp,(int)(p+ *plength),
125 		(int)(omax+ *pp));
126 
127 #endif
128 	if (*plength > (omax - (p - *pp)))
129 		{
130 		ASN1err(ASN1_F_ASN1_GET_OBJECT,ASN1_R_TOO_LONG);
131 		/* Set this so that even if things are not long enough
132 		 * the values are set correctly */
133 		ret|=0x80;
134 		}
135 	*pp=p;
136 	return(ret|inf);
137 err:
138 	ASN1err(ASN1_F_ASN1_GET_OBJECT,ASN1_R_HEADER_TOO_LONG);
139 	return(0x80);
140 	}
141 
142 static int asn1_get_length(unsigned char **pp, int *inf, long *rl, int max)
143 	{
144 	unsigned char *p= *pp;
145 	unsigned long ret=0;
146 	int i;
147 
148 	if (max-- < 1) return(0);
149 	if (*p == 0x80)
150 		{
151 		*inf=1;
152 		ret=0;
153 		p++;
154 		}
155 	else
156 		{
157 		*inf=0;
158 		i= *p&0x7f;
159 		if (*(p++) & 0x80)
160 			{
161 			if (i > sizeof(long))
162 				return 0;
163 			if (max-- == 0) return(0);
164 			while (i-- > 0)
165 				{
166 				ret<<=8L;
167 				ret|= *(p++);
168 				if (max-- == 0) return(0);
169 				}
170 			}
171 		else
172 			ret=i;
173 		}
174 	if (ret > LONG_MAX)
175 		return 0;
176 	*pp=p;
177 	*rl=(long)ret;
178 	return(1);
179 	}
180 
181 /* class 0 is constructed
182  * constructed == 2 for indefinite length constructed */
183 void ASN1_put_object(unsigned char **pp, int constructed, int length, int tag,
184 	     int xclass)
185 	{
186 	unsigned char *p= *pp;
187 	int i, ttag;
188 
189 	i=(constructed)?V_ASN1_CONSTRUCTED:0;
190 	i|=(xclass&V_ASN1_PRIVATE);
191 	if (tag < 31)
192 		*(p++)=i|(tag&V_ASN1_PRIMITIVE_TAG);
193 	else
194 		{
195 		*(p++)=i|V_ASN1_PRIMITIVE_TAG;
196 		for(i = 0, ttag = tag; ttag > 0; i++) ttag >>=7;
197 		ttag = i;
198 		while(i-- > 0)
199 			{
200 			p[i] = tag & 0x7f;
201 			if(i != (ttag - 1)) p[i] |= 0x80;
202 			tag >>= 7;
203 			}
204 		p += ttag;
205 		}
206 	if ((constructed == 2) && (length == 0))
207 		*(p++)=0x80; /* der_put_length would output 0 instead */
208 	else
209 		asn1_put_length(&p,length);
210 	*pp=p;
211 	}
212 
213 static void asn1_put_length(unsigned char **pp, int length)
214 	{
215 	unsigned char *p= *pp;
216 	int i,l;
217 	if (length <= 127)
218 		*(p++)=(unsigned char)length;
219 	else
220 		{
221 		l=length;
222 		for (i=0; l > 0; i++)
223 			l>>=8;
224 		*(p++)=i|0x80;
225 		l=i;
226 		while (i-- > 0)
227 			{
228 			p[i]=length&0xff;
229 			length>>=8;
230 			}
231 		p+=l;
232 		}
233 	*pp=p;
234 	}
235 
236 int ASN1_object_size(int constructed, int length, int tag)
237 	{
238 	int ret;
239 
240 	ret=length;
241 	ret++;
242 	if (tag >= 31)
243 		{
244 		while (tag > 0)
245 			{
246 			tag>>=7;
247 			ret++;
248 			}
249 		}
250 	if ((length == 0) && (constructed == 2))
251 		ret+=2;
252 	ret++;
253 	if (length > 127)
254 		{
255 		while (length > 0)
256 			{
257 			length>>=8;
258 			ret++;
259 			}
260 		}
261 	return(ret);
262 	}
263 
264 int asn1_Finish(ASN1_CTX *c)
265 	{
266 	if ((c->inf == (1|V_ASN1_CONSTRUCTED)) && (!c->eos))
267 		{
268 		if (!ASN1_check_infinite_end(&c->p,c->slen))
269 			{
270 			c->error=ERR_R_MISSING_ASN1_EOS;
271 			return(0);
272 			}
273 		}
274 	if (	((c->slen != 0) && !(c->inf & 1)) ||
275 		((c->slen < 0) && (c->inf & 1)))
276 		{
277 		c->error=ERR_R_ASN1_LENGTH_MISMATCH;
278 		return(0);
279 		}
280 	return(1);
281 	}
282 
283 int asn1_GetSequence(ASN1_CTX *c, long *length)
284 	{
285 	unsigned char *q;
286 
287 	q=c->p;
288 	c->inf=ASN1_get_object(&(c->p),&(c->slen),&(c->tag),&(c->xclass),
289 		*length);
290 	if (c->inf & 0x80)
291 		{
292 		c->error=ERR_R_BAD_GET_ASN1_OBJECT_CALL;
293 		return(0);
294 		}
295 	if (c->tag != V_ASN1_SEQUENCE)
296 		{
297 		c->error=ERR_R_EXPECTING_AN_ASN1_SEQUENCE;
298 		return(0);
299 		}
300 	(*length)-=(c->p-q);
301 	if (c->max && (*length < 0))
302 		{
303 		c->error=ERR_R_ASN1_LENGTH_MISMATCH;
304 		return(0);
305 		}
306 	if (c->inf == (1|V_ASN1_CONSTRUCTED))
307 		c->slen= *length+ *(c->pp)-c->p;
308 	c->eos=0;
309 	return(1);
310 	}
311 
312 ASN1_STRING *ASN1_STRING_dup(ASN1_STRING *str)
313 	{
314 	ASN1_STRING *ret;
315 
316 	if (str == NULL) return(NULL);
317 	if ((ret=ASN1_STRING_type_new(str->type)) == NULL)
318 		return(NULL);
319 	if (!ASN1_STRING_set(ret,str->data,str->length))
320 		{
321 		ASN1_STRING_free(ret);
322 		return(NULL);
323 		}
324 	ret->flags = str->flags;
325 	return(ret);
326 	}
327 
328 int ASN1_STRING_set(ASN1_STRING *str, const void *_data, int len)
329 	{
330 	unsigned char *c;
331 	const char *data=_data;
332 
333 	if (len < 0)
334 		{
335 		if (data == NULL)
336 			return(0);
337 		else
338 			len=strlen(data);
339 		}
340 	if ((str->length < len) || (str->data == NULL))
341 		{
342 		c=str->data;
343 		if (c == NULL)
344 			str->data=OPENSSL_malloc(len+1);
345 		else
346 			str->data=OPENSSL_realloc(c,len+1);
347 
348 		if (str->data == NULL)
349 			{
350 			str->data=c;
351 			return(0);
352 			}
353 		}
354 	str->length=len;
355 	if (data != NULL)
356 		{
357 		memcpy(str->data,data,len);
358 		/* an allowance for strings :-) */
359 		str->data[len]='\0';
360 		}
361 	return(1);
362 	}
363 
364 ASN1_STRING *ASN1_STRING_new(void)
365 	{
366 	return(ASN1_STRING_type_new(V_ASN1_OCTET_STRING));
367 	}
368 
369 
370 ASN1_STRING *ASN1_STRING_type_new(int type)
371 	{
372 	ASN1_STRING *ret;
373 
374 	ret=(ASN1_STRING *)OPENSSL_malloc(sizeof(ASN1_STRING));
375 	if (ret == NULL)
376 		{
377 		ASN1err(ASN1_F_ASN1_STRING_TYPE_NEW,ERR_R_MALLOC_FAILURE);
378 		return(NULL);
379 		}
380 	ret->length=0;
381 	ret->type=type;
382 	ret->data=NULL;
383 	ret->flags=0;
384 	return(ret);
385 	}
386 
387 void ASN1_STRING_free(ASN1_STRING *a)
388 	{
389 	if (a == NULL) return;
390 	if (a->data != NULL) OPENSSL_free(a->data);
391 	OPENSSL_free(a);
392 	}
393 
394 int ASN1_STRING_cmp(ASN1_STRING *a, ASN1_STRING *b)
395 	{
396 	int i;
397 
398 	i=(a->length-b->length);
399 	if (i == 0)
400 		{
401 		i=memcmp(a->data,b->data,a->length);
402 		if (i == 0)
403 			return(a->type-b->type);
404 		else
405 			return(i);
406 		}
407 	else
408 		return(i);
409 	}
410 
411 void asn1_add_error(unsigned char *address, int offset)
412 	{
413 	char buf1[DECIMAL_SIZE(address)+1],buf2[DECIMAL_SIZE(offset)+1];
414 
415 	snprintf(buf1,sizeof buf1,"%lu",(unsigned long)address);
416 	snprintf(buf2,sizeof buf2,"%d",offset);
417 	ERR_add_error_data(4,"address=",buf1," offset=",buf2);
418 	}
419 
420 int ASN1_STRING_length(ASN1_STRING *x)
421 { return M_ASN1_STRING_length(x); }
422 
423 void ASN1_STRING_length_set(ASN1_STRING *x, int len)
424 { M_ASN1_STRING_length_set(x, len); return; }
425 
426 int ASN1_STRING_type(ASN1_STRING *x)
427 { return M_ASN1_STRING_type(x); }
428 
429 unsigned char * ASN1_STRING_data(ASN1_STRING *x)
430 { return M_ASN1_STRING_data(x); }
431