1 /* $OpenBSD: asn1pars.c,v 1.11 2022/01/12 22:55:51 tb 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 /* A nice addition from Dr Stephen Henson <steve@openssl.org> to
60  * add the -strparse option which parses nested binary structures
61  */
62 
63 #include <stdio.h>
64 #include <stdlib.h>
65 #include <limits.h>
66 #include <string.h>
67 
68 #include "apps.h"
69 #include "progs.h"
70 
71 #include <openssl/err.h>
72 #include <openssl/evp.h>
73 #include <openssl/pem.h>
74 #include <openssl/x509.h>
75 
76 static struct {
77 	char *derfile;
78 	int dump;
79 	char *genconf;
80 	char *genstr;
81 	int indent;
82 	char *infile;
83 	int informat;
84 	unsigned int length;
85 	int noout;
86 	int offset;
87 	char *oidfile;
88 	STACK_OF(OPENSSL_STRING) *osk;
89 } asn1pars_config;
90 
91 static int
92 asn1pars_opt_dlimit(char *arg)
93 {
94 	const char *errstr;
95 
96 	asn1pars_config.dump = strtonum(arg, 1, INT_MAX, &errstr);
97 	if (errstr) {
98 		fprintf(stderr, "-dlimit must be from 1 to INT_MAX: %s\n",
99 		    errstr);
100 		return (-1);
101 	}
102 	return (0);
103 }
104 
105 static int
106 asn1pars_opt_length(char *arg)
107 {
108 	const char *errstr;
109 
110 	asn1pars_config.length = strtonum(arg, 1, UINT_MAX, &errstr);
111 	if (errstr) {
112 		fprintf(stderr, "-length must be from 1 to UINT_MAX: %s\n",
113 		    errstr);
114 		return (-1);
115 	}
116 	return (0);
117 }
118 
119 static int
120 asn1pars_opt_strparse(char *arg)
121 {
122 	if (sk_OPENSSL_STRING_push(asn1pars_config.osk, arg) == 0) {
123 		fprintf(stderr, "-strparse cannot add argument\n");
124 		return (-1);
125 	}
126 	return (0);
127 }
128 
129 static const struct option asn1pars_options[] = {
130 	{
131 		.name = "dump",
132 		.desc = "Dump unknown data in hex form",
133 		.type = OPTION_VALUE,
134 		.value = -1,
135 		.opt.value = &asn1pars_config.dump,
136 	},
137 	{
138 		.name = "dlimit",
139 		.argname = "num",
140 		.desc = "Dump the first num bytes of unknown data in hex form",
141 		.type = OPTION_ARG_FUNC,
142 		.opt.argfunc = asn1pars_opt_dlimit,
143 	},
144 	{
145 		.name = "genconf",
146 		.argname = "file",
147 		.desc = "File to generate ASN.1 structure from",
148 		.type = OPTION_ARG,
149 		.opt.arg = &asn1pars_config.genconf,
150 	},
151 	{
152 		.name = "genstr",
153 		.argname = "string",
154 		.desc = "String to generate ASN.1 structure from",
155 		.type = OPTION_ARG,
156 		.opt.arg = &asn1pars_config.genstr,
157 	},
158 	{
159 		.name = "i",
160 		.desc = "Indent output according to depth of structures",
161 		.type = OPTION_FLAG,
162 		.opt.flag = &asn1pars_config.indent,
163 	},
164 	{
165 		.name = "in",
166 		.argname = "file",
167 		.desc = "The input file (default stdin)",
168 		.type = OPTION_ARG,
169 		.opt.arg = &asn1pars_config.infile,
170 	},
171 	{
172 		.name = "inform",
173 		.argname = "fmt",
174 		.desc = "Input format (DER, TXT or PEM (default))",
175 		.type = OPTION_ARG_FORMAT,
176 		.opt.value = &asn1pars_config.informat,
177 	},
178 	{
179 		.name = "length",
180 		.argname = "num",
181 		.desc = "Number of bytes to parse (default until EOF)",
182 		.type = OPTION_ARG_FUNC,
183 		.opt.argfunc = asn1pars_opt_length,
184 	},
185 	{
186 		.name = "noout",
187 		.desc = "Do not produce any output",
188 		.type = OPTION_FLAG,
189 		.opt.flag = &asn1pars_config.noout,
190 	},
191 	{
192 		.name = "offset",
193 		.argname = "num",
194 		.desc = "Offset to begin parsing",
195 		.type = OPTION_ARG_INT,
196 		.opt.value = &asn1pars_config.offset,
197 	},
198 	{
199 		.name = "oid",
200 		.argname = "file",
201 		.desc = "File containing additional object identifiers (OIDs)",
202 		.type = OPTION_ARG,
203 		.opt.arg = &asn1pars_config.oidfile,
204 	},
205 	{
206 		.name = "out",
207 		.argname = "file",
208 		.desc = "Output file in DER format",
209 		.type = OPTION_ARG,
210 		.opt.arg = &asn1pars_config.derfile,
211 	},
212 	{
213 		.name = "strparse",
214 		.argname = "offset",
215 		.desc = "Parse the content octets of ASN.1 object starting at"
216 		" offset",
217 		.type = OPTION_ARG_FUNC,
218 		.opt.argfunc = asn1pars_opt_strparse,
219 	},
220 	{ NULL },
221 };
222 
223 static void
224 asn1pars_usage()
225 {
226 	fprintf(stderr,
227 	    "usage: asn1parse [-i] [-dlimit num] [-dump] [-genconf file] "
228 	    "[-genstr string]\n"
229 	    "    [-in file] [-inform fmt] [-length num] [-noout] [-offset num] "
230 	    "[-oid file]\n"
231 	    "    [-out file] [-strparse offset]\n\n");
232 	options_usage(asn1pars_options);
233 }
234 
235 static int do_generate(BIO *bio, char *genstr, char *genconf, BUF_MEM *buf);
236 
237 int
238 asn1parse_main(int argc, char **argv)
239 {
240 	int i, j, ret = 1;
241 	long num, tmplen;
242 	BIO *in = NULL, *out = NULL, *b64 = NULL, *derout = NULL;
243 	char *str = NULL;
244 	const char *errstr = NULL;
245 	unsigned char *tmpbuf;
246 	const unsigned char *ctmpbuf;
247 	BUF_MEM *buf = NULL;
248 	ASN1_TYPE *at = NULL;
249 
250 	if (single_execution) {
251 		if (pledge("stdio cpath wpath rpath", NULL) == -1) {
252 			perror("pledge");
253 			exit(1);
254 		}
255 	}
256 
257 	memset(&asn1pars_config, 0, sizeof(asn1pars_config));
258 
259 	asn1pars_config.informat = FORMAT_PEM;
260 	if ((asn1pars_config.osk = sk_OPENSSL_STRING_new_null()) == NULL) {
261 		BIO_printf(bio_err, "Memory allocation failure\n");
262 		goto end;
263 	}
264 
265 	if (options_parse(argc, argv, asn1pars_options, NULL, NULL) != 0) {
266 		asn1pars_usage();
267 		return (1);
268 	}
269 
270 	in = BIO_new(BIO_s_file());
271 	out = BIO_new(BIO_s_file());
272 	if ((in == NULL) || (out == NULL)) {
273 		ERR_print_errors(bio_err);
274 		goto end;
275 	}
276 	BIO_set_fp(out, stdout, BIO_NOCLOSE | BIO_FP_TEXT);
277 
278 	if (asn1pars_config.oidfile != NULL) {
279 		if (BIO_read_filename(in, asn1pars_config.oidfile) <= 0) {
280 			BIO_printf(bio_err, "problems opening %s\n",
281 			    asn1pars_config.oidfile);
282 			ERR_print_errors(bio_err);
283 			goto end;
284 		}
285 		OBJ_create_objects(in);
286 	}
287 	if (asn1pars_config.infile == NULL)
288 		BIO_set_fp(in, stdin, BIO_NOCLOSE);
289 	else {
290 		if (BIO_read_filename(in, asn1pars_config.infile) <= 0) {
291 			perror(asn1pars_config.infile);
292 			goto end;
293 		}
294 	}
295 
296 	if (asn1pars_config.derfile) {
297 		if (!(derout = BIO_new_file(asn1pars_config.derfile, "wb"))) {
298 			BIO_printf(bio_err, "problems opening %s\n",
299 			    asn1pars_config.derfile);
300 			ERR_print_errors(bio_err);
301 			goto end;
302 		}
303 	}
304 	if ((buf = BUF_MEM_new()) == NULL)
305 		goto end;
306 	if (!BUF_MEM_grow(buf, BUFSIZ * 8))
307 		goto end;	/* Pre-allocate :-) */
308 
309 	if (asn1pars_config.genstr || asn1pars_config.genconf) {
310 		num = do_generate(bio_err, asn1pars_config.genstr,
311 		    asn1pars_config.genconf, buf);
312 		if (num < 0) {
313 			ERR_print_errors(bio_err);
314 			goto end;
315 		}
316 	} else {
317 
318 		if (asn1pars_config.informat == FORMAT_PEM) {
319 			BIO *tmp;
320 
321 			if ((b64 = BIO_new(BIO_f_base64())) == NULL)
322 				goto end;
323 			BIO_push(b64, in);
324 			tmp = in;
325 			in = b64;
326 			b64 = tmp;
327 		}
328 		num = 0;
329 		for (;;) {
330 			if (!BUF_MEM_grow(buf, (int) num + BUFSIZ))
331 				goto end;
332 			i = BIO_read(in, &(buf->data[num]), BUFSIZ);
333 			if (i <= 0)
334 				break;
335 			num += i;
336 		}
337 	}
338 	str = buf->data;
339 
340 	/* If any structs to parse go through in sequence */
341 
342 	if (sk_OPENSSL_STRING_num(asn1pars_config.osk)) {
343 		tmpbuf = (unsigned char *) str;
344 		tmplen = num;
345 		for (i = 0; i < sk_OPENSSL_STRING_num(asn1pars_config.osk);
346 		     i++) {
347 			ASN1_TYPE *atmp;
348 			int typ;
349 			j = strtonum(
350 			    sk_OPENSSL_STRING_value(asn1pars_config.osk, i),
351 			    1, INT_MAX, &errstr);
352 			if (errstr) {
353 				BIO_printf(bio_err,
354 				    "'%s' is an invalid number: %s\n",
355 				    sk_OPENSSL_STRING_value(asn1pars_config.osk,
356 				    i), errstr);
357 				continue;
358 			}
359 			tmpbuf += j;
360 			tmplen -= j;
361 			atmp = at;
362 			ctmpbuf = tmpbuf;
363 			at = d2i_ASN1_TYPE(NULL, &ctmpbuf, tmplen);
364 			ASN1_TYPE_free(atmp);
365 			if (!at) {
366 				BIO_printf(bio_err, "Error parsing structure\n");
367 				ERR_print_errors(bio_err);
368 				goto end;
369 			}
370 			typ = ASN1_TYPE_get(at);
371 			if ((typ == V_ASN1_OBJECT) ||
372 			    (typ == V_ASN1_NULL)) {
373 				BIO_printf(bio_err, "Can't parse %s type\n",
374 				    typ == V_ASN1_NULL ? "NULL" : "OBJECT");
375 				ERR_print_errors(bio_err);
376 				goto end;
377 			}
378 			/* hmm... this is a little evil but it works */
379 			tmpbuf = at->value.asn1_string->data;
380 			tmplen = at->value.asn1_string->length;
381 		}
382 		str = (char *) tmpbuf;
383 		num = tmplen;
384 	}
385 	if (asn1pars_config.offset >= num) {
386 		BIO_printf(bio_err, "Error: offset too large\n");
387 		goto end;
388 	}
389 	num -= asn1pars_config.offset;
390 
391 	if ((asn1pars_config.length == 0) ||
392 	    ((long)asn1pars_config.length > num))
393 		asn1pars_config.length = (unsigned int) num;
394 	if (derout) {
395 		if (BIO_write(derout, str + asn1pars_config.offset,
396 		    asn1pars_config.length) != (int)asn1pars_config.length) {
397 			BIO_printf(bio_err, "Error writing output\n");
398 			ERR_print_errors(bio_err);
399 			goto end;
400 		}
401 	}
402 	if (!asn1pars_config.noout &&
403 	    !ASN1_parse_dump(out,
404 	    (unsigned char *)&(str[asn1pars_config.offset]),
405 	    asn1pars_config.length, asn1pars_config.indent,
406 	    asn1pars_config.dump)) {
407 		ERR_print_errors(bio_err);
408 		goto end;
409 	}
410 	ret = 0;
411  end:
412 	BIO_free(derout);
413 	BIO_free(in);
414 	BIO_free_all(out);
415 	BIO_free(b64);
416 	if (ret != 0)
417 		ERR_print_errors(bio_err);
418 	BUF_MEM_free(buf);
419 	ASN1_TYPE_free(at);
420 	sk_OPENSSL_STRING_free(asn1pars_config.osk);
421 	OBJ_cleanup();
422 
423 	return (ret);
424 }
425 
426 static int
427 do_generate(BIO *bio, char *genstr, char *genconf, BUF_MEM *buf)
428 {
429 	CONF *cnf = NULL;
430 	int len;
431 	long errline;
432 	unsigned char *p;
433 	ASN1_TYPE *atyp = NULL;
434 
435 	if (genconf) {
436 		cnf = NCONF_new(NULL);
437 		if (!NCONF_load(cnf, genconf, &errline))
438 			goto conferr;
439 		if (!genstr)
440 			genstr = NCONF_get_string(cnf, "default", "asn1");
441 		if (!genstr) {
442 			BIO_printf(bio, "Can't find 'asn1' in '%s'\n", genconf);
443 			goto err;
444 		}
445 	}
446 	atyp = ASN1_generate_nconf(genstr, cnf);
447 	NCONF_free(cnf);
448 	cnf = NULL;
449 
450 	if (!atyp)
451 		return -1;
452 
453 	len = i2d_ASN1_TYPE(atyp, NULL);
454 	if (len <= 0)
455 		goto err;
456 
457 	if (!BUF_MEM_grow(buf, len))
458 		goto err;
459 
460 	p = (unsigned char *) buf->data;
461 
462 	i2d_ASN1_TYPE(atyp, &p);
463 
464 	ASN1_TYPE_free(atyp);
465 	return len;
466 
467  conferr:
468 
469 	if (errline > 0)
470 		BIO_printf(bio, "Error on line %ld of config file '%s'\n",
471 		    errline, genconf);
472 	else
473 		BIO_printf(bio, "Error loading config file '%s'\n", genconf);
474 
475  err:
476 	NCONF_free(cnf);
477 	ASN1_TYPE_free(atyp);
478 
479 	return -1;
480 
481 }
482