1 /* $OpenBSD: asn1_par.c,v 1.27 2019/03/24 16:07:25 beck Exp $ */
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 
61 #include <openssl/asn1.h>
62 #include <openssl/buffer.h>
63 #include <openssl/objects.h>
64 
65 static int asn1_print_info(BIO *bp, int tag, int xclass, int constructed,
66     int indent);
67 static int asn1_parse2(BIO *bp, const unsigned char **pp, long length,
68     int offset, int depth, int indent, int dump);
69 
70 static int
71 asn1_print_info(BIO *bp, int tag, int xclass, int constructed,
72     int indent)
73 {
74 	char str[128];
75 	const char *p;
76 
77 	if (constructed & V_ASN1_CONSTRUCTED)
78 		p="cons: ";
79 	else
80 		p="prim: ";
81 	if (BIO_write(bp, p, 6) < 6)
82 		goto err;
83 	BIO_indent(bp, indent, 128);
84 
85 	p = str;
86 	if ((xclass & V_ASN1_PRIVATE) == V_ASN1_PRIVATE)
87 		snprintf(str, sizeof str, "priv [ %d ] ", tag);
88 	else if ((xclass & V_ASN1_CONTEXT_SPECIFIC) == V_ASN1_CONTEXT_SPECIFIC)
89 		snprintf(str, sizeof str, "cont [ %d ]", tag);
90 	else if ((xclass & V_ASN1_APPLICATION) == V_ASN1_APPLICATION)
91 		snprintf(str, sizeof str, "appl [ %d ]", tag);
92 	else if (tag > 30)
93 		snprintf(str, sizeof str, "<ASN1 %d>", tag);
94 	else
95 		p = ASN1_tag2str(tag);
96 
97 	if (BIO_printf(bp, "%-18s", p) <= 0)
98 		goto err;
99 	return (1);
100 err:
101 	return (0);
102 }
103 
104 int
105 ASN1_parse(BIO *bp, const unsigned char *pp, long len, int indent)
106 {
107 	return (asn1_parse2(bp, &pp, len, 0, 0, indent, 0));
108 }
109 
110 int
111 ASN1_parse_dump(BIO *bp, const unsigned char *pp, long len, int indent, int dump)
112 {
113 	return (asn1_parse2(bp, &pp, len, 0, 0, indent, dump));
114 }
115 
116 static int
117 asn1_parse2(BIO *bp, const unsigned char **pp, long length, int offset,
118     int depth, int indent, int dump)
119 {
120 	const unsigned char *p, *ep, *tot, *op, *opp;
121 	long len;
122 	int tag, xclass, ret = 0;
123 	int nl, hl, j, r;
124 	ASN1_OBJECT *o = NULL;
125 	ASN1_OCTET_STRING *os = NULL;
126 	/* ASN1_BMPSTRING *bmp=NULL;*/
127 	int dump_indent;
128 
129 	dump_indent = 6;	/* Because we know BIO_dump_indent() */
130 	p = *pp;
131 	tot = p + length;
132 	op = p - 1;
133 	if (depth > 128) {
134 		BIO_printf(bp, "Max depth exceeded\n");
135 		goto end;
136 	}
137 	while ((p < tot) && (op < p)) {
138 		op = p;
139 		j = ASN1_get_object(&p, &len, &tag, &xclass, length);
140 
141 		if (j & 0x80) {
142 			if (BIO_write(bp, "Error in encoding\n", 18) <= 0)
143 				goto end;
144 			ret = 0;
145 			goto end;
146 		}
147 		hl = (p - op);
148 		length -= hl;
149 		/* if j == 0x21 it is a constructed indefinite length object */
150 		if (BIO_printf(bp, "%5ld:", (long)offset +
151 		    (long)(op - *pp)) <= 0)
152 		    goto end;
153 
154 		if (j != (V_ASN1_CONSTRUCTED | 1)) {
155 			if (BIO_printf(bp, "d=%-2d hl=%ld l=%4ld ",
156 			    depth, (long)hl, len) <= 0)
157 				goto end;
158 		} else {
159 			if (BIO_printf(bp, "d=%-2d hl=%ld l=inf  ",
160 			    depth, (long)hl) <= 0)
161 				goto end;
162 		}
163 		if (!asn1_print_info(bp, tag, xclass, j, (indent) ? depth : 0))
164 			goto end;
165 		if (j & V_ASN1_CONSTRUCTED) {
166 			ep = p + len;
167 			if (BIO_write(bp, "\n", 1) <= 0)
168 				goto end;
169 			if (len > length) {
170 				BIO_printf(bp, "length is greater than %ld\n",
171 				    length);
172 				ret = 0;
173 				goto end;
174 			}
175 			if ((j == 0x21) && (len == 0)) {
176 				for (;;) {
177 					r = asn1_parse2(bp, &p, (long)(tot - p),
178 					    offset + (p - *pp), depth + 1,
179 					    indent, dump);
180 					if (r == 0) {
181 						ret = 0;
182 						goto end;
183 					}
184 					if ((r == 2) || (p >= tot)) {
185 						len = (long)(p - ep);
186 						break;
187 					}
188 				}
189 			} else {
190 				while (p < ep) {
191 					r = asn1_parse2(bp, &p, (long)(ep - p),
192 					    offset + (p - *pp), depth + 1,
193 					    indent, dump);
194 					if (r == 0) {
195 						ret = 0;
196 						goto end;
197 					}
198 				}
199 			}
200 		} else if (xclass != 0) {
201 			p += len;
202 			if (BIO_write(bp, "\n", 1) <= 0)
203 				goto end;
204 		} else {
205 			nl = 0;
206 			if ((tag == V_ASN1_PRINTABLESTRING) ||
207 			    (tag == V_ASN1_T61STRING) ||
208 			    (tag == V_ASN1_IA5STRING) ||
209 			    (tag == V_ASN1_VISIBLESTRING) ||
210 			    (tag == V_ASN1_NUMERICSTRING) ||
211 			    (tag == V_ASN1_UTF8STRING) ||
212 			    (tag == V_ASN1_UTCTIME) ||
213 			    (tag == V_ASN1_GENERALIZEDTIME)) {
214 				if (BIO_write(bp, ":", 1) <= 0)
215 					goto end;
216 				if ((len > 0) &&
217 				    BIO_write(bp, (const char *)p, (int)len) !=
218 				    (int)len)
219 					goto end;
220 			} else if (tag == V_ASN1_OBJECT) {
221 				opp = op;
222 				if (d2i_ASN1_OBJECT(&o, &opp, len + hl) !=
223 				    NULL) {
224 					if (BIO_write(bp, ":", 1) <= 0)
225 						goto end;
226 					i2a_ASN1_OBJECT(bp, o);
227 				} else {
228 					if (BIO_write(bp, ":BAD OBJECT",
229 					    11) <= 0)
230 						goto end;
231 				}
232 			} else if (tag == V_ASN1_BOOLEAN) {
233 				int ii;
234 
235 				opp = op;
236 				ii = d2i_ASN1_BOOLEAN(NULL, &opp, len + hl);
237 				if (ii < 0) {
238 					if (BIO_write(bp, "Bad boolean\n",
239 					    12) <= 0)
240 						goto end;
241 				}
242 				BIO_printf(bp, ":%d", ii);
243 			} else if (tag == V_ASN1_BMPSTRING) {
244 				/* do the BMP thang */
245 			} else if (tag == V_ASN1_OCTET_STRING) {
246 				int i, printable = 1;
247 
248 				opp = op;
249 				os = d2i_ASN1_OCTET_STRING(NULL, &opp, len + hl);
250 				if (os != NULL && os->length > 0) {
251 					opp = os->data;
252 					/* testing whether the octet string is
253 					 * printable */
254 					for (i = 0; i < os->length; i++) {
255 						if (((opp[i] < ' ') &&
256 						    (opp[i] != '\n') &&
257 						    (opp[i] != '\r') &&
258 						    (opp[i] != '\t')) ||
259 						    (opp[i] > '~')) {
260 							printable = 0;
261 							break;
262 						}
263 					}
264 					if (printable) {
265 						/* printable string */
266 						if (BIO_write(bp, ":", 1) <= 0)
267 							goto end;
268 						if (BIO_write(bp, (const char *)opp,
269 							    os->length) <= 0)
270 							goto end;
271 					} else if (!dump) {
272 						/* not printable => print octet string
273 						 * as hex dump */
274 						if (BIO_write(bp, "[HEX DUMP]:", 11) <= 0)
275 							goto end;
276 						for (i = 0; i < os->length; i++) {
277 							if (BIO_printf(bp,
278 							    "%02X", opp[i]) <= 0)
279 								goto end;
280 						}
281 					} else {
282 						/* print the normal dump */
283 						if (!nl) {
284 							if (BIO_write(bp, "\n", 1) <= 0)
285 								goto end;
286 						}
287 						if (BIO_dump_indent(bp,
288 						    (const char *)opp,
289 						    ((dump == -1 || dump >
290 						    os->length) ? os->length : dump),
291 						    dump_indent) <= 0)
292 							goto end;
293 						nl = 1;
294 					}
295 				}
296 				ASN1_OCTET_STRING_free(os);
297 				os = NULL;
298 			} else if (tag == V_ASN1_INTEGER) {
299 				ASN1_INTEGER *bs;
300 				int i;
301 
302 				opp = op;
303 				bs = d2i_ASN1_INTEGER(NULL, &opp, len + hl);
304 				if (bs != NULL) {
305 					if (BIO_write(bp, ":", 1) <= 0)
306 						goto end;
307 					if (bs->type == V_ASN1_NEG_INTEGER)
308 						if (BIO_write(bp, "-", 1) <= 0)
309 							goto end;
310 					for (i = 0; i < bs->length; i++) {
311 						if (BIO_printf(bp, "%02X",
312 						    bs->data[i]) <= 0)
313 							goto end;
314 					}
315 					if (bs->length == 0) {
316 						if (BIO_write(bp, "00", 2) <= 0)
317 							goto end;
318 					}
319 				} else {
320 					if (BIO_write(bp, "BAD INTEGER", 11) <= 0)
321 						goto end;
322 				}
323 				ASN1_INTEGER_free(bs);
324 			} else if (tag == V_ASN1_ENUMERATED) {
325 				ASN1_ENUMERATED *bs;
326 				int i;
327 
328 				opp = op;
329 				bs = d2i_ASN1_ENUMERATED(NULL, &opp, len + hl);
330 				if (bs != NULL) {
331 					if (BIO_write(bp, ":", 1) <= 0)
332 						goto end;
333 					if (bs->type == V_ASN1_NEG_ENUMERATED)
334 						if (BIO_write(bp, "-", 1) <= 0)
335 							goto end;
336 					for (i = 0; i < bs->length; i++) {
337 						if (BIO_printf(bp, "%02X",
338 						    bs->data[i]) <= 0)
339 							goto end;
340 					}
341 					if (bs->length == 0) {
342 						if (BIO_write(bp, "00", 2) <= 0)
343 							goto end;
344 					}
345 				} else {
346 					if (BIO_write(bp, "BAD ENUMERATED", 14) <= 0)
347 						goto end;
348 				}
349 				ASN1_ENUMERATED_free(bs);
350 			} else if (len > 0 && dump) {
351 				if (!nl) {
352 					if (BIO_write(bp, "\n", 1) <= 0)
353 						goto end;
354 				}
355 				if (BIO_dump_indent(bp, (const char *)p,
356 				    ((dump == -1 || dump > len) ? len : dump),
357 				    dump_indent) <= 0)
358 					goto end;
359 				nl = 1;
360 			}
361 
362 			if (!nl) {
363 				if (BIO_write(bp, "\n", 1) <= 0)
364 					goto end;
365 			}
366 			p += len;
367 			if ((tag == V_ASN1_EOC) && (xclass == 0)) {
368 				ret = 2; /* End of sequence */
369 				goto end;
370 			}
371 		}
372 		length -= len;
373 	}
374 	ret = 1;
375 
376 end:
377 	if (o != NULL)
378 		ASN1_OBJECT_free(o);
379 	ASN1_OCTET_STRING_free(os);
380 	*pp = p;
381 	return (ret);
382 }
383 
384 const char *
385 ASN1_tag2str(int tag)
386 {
387 	static const char * const tag2str[] = {
388 		"EOC", "BOOLEAN", "INTEGER", "BIT STRING", "OCTET STRING", /* 0-4 */
389 		"NULL", "OBJECT", "OBJECT DESCRIPTOR", "EXTERNAL", "REAL", /* 5-9 */
390 		"ENUMERATED", "<ASN1 11>", "UTF8STRING", "<ASN1 13>", 	    /* 10-13 */
391 		"<ASN1 14>", "<ASN1 15>", "SEQUENCE", "SET", 		    /* 15-17 */
392 		"NUMERICSTRING", "PRINTABLESTRING", "T61STRING",	    /* 18-20 */
393 		"VIDEOTEXSTRING", "IA5STRING", "UTCTIME", "GENERALIZEDTIME", /* 21-24 */
394 		"GRAPHICSTRING", "VISIBLESTRING", "GENERALSTRING",	    /* 25-27 */
395 		"UNIVERSALSTRING", "<ASN1 29>", "BMPSTRING"		    /* 28-30 */
396 	};
397 
398 	if ((tag == V_ASN1_NEG_INTEGER) || (tag == V_ASN1_NEG_ENUMERATED))
399 		tag &= ~0x100;
400 
401 	if (tag < 0 || tag > 30)
402 		return "(unknown)";
403 	return tag2str[tag];
404 }
405