1 /* $OpenBSD: a_strex.c,v 1.28 2018/05/19 10:46:28 tb Exp $ */
2 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
3  * project 2000.
4  */
5 /* ====================================================================
6  * Copyright (c) 2000 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in
17  *    the documentation and/or other materials provided with the
18  *    distribution.
19  *
20  * 3. All advertising materials mentioning features or use of this
21  *    software must display the following acknowledgment:
22  *    "This product includes software developed by the OpenSSL Project
23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
24  *
25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26  *    endorse or promote products derived from this software without
27  *    prior written permission. For written permission, please contact
28  *    licensing@OpenSSL.org.
29  *
30  * 5. Products derived from this software may not be called "OpenSSL"
31  *    nor may "OpenSSL" appear in their names without prior written
32  *    permission of the OpenSSL Project.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50  * OF THE POSSIBILITY OF SUCH DAMAGE.
51  * ====================================================================
52  *
53  * This product includes cryptographic software written by Eric Young
54  * (eay@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 #include <stdio.h>
60 #include <string.h>
61 
62 #include <openssl/asn1.h>
63 #include <openssl/crypto.h>
64 #include <openssl/x509.h>
65 
66 #include "asn1_locl.h"
67 
68 #include "charmap.h"
69 
70 /* ASN1_STRING_print_ex() and X509_NAME_print_ex().
71  * Enhanced string and name printing routines handling
72  * multibyte characters, RFC2253 and a host of other
73  * options.
74  */
75 
76 #define CHARTYPE_BS_ESC		(ASN1_STRFLGS_ESC_2253 | CHARTYPE_FIRST_ESC_2253 | CHARTYPE_LAST_ESC_2253)
77 
78 #define ESC_FLAGS (ASN1_STRFLGS_ESC_2253 | \
79 		  ASN1_STRFLGS_ESC_QUOTE | \
80 		  ASN1_STRFLGS_ESC_CTRL | \
81 		  ASN1_STRFLGS_ESC_MSB)
82 
83 
84 /* Three IO functions for sending data to memory, a BIO and
85  * and a FILE pointer.
86  */
87 static int
88 send_bio_chars(void *arg, const void *buf, int len)
89 {
90 	if (!arg)
91 		return 1;
92 	if (BIO_write(arg, buf, len) != len)
93 		return 0;
94 	return 1;
95 }
96 
97 static int
98 send_fp_chars(void *arg, const void *buf, int len)
99 {
100 	if (!arg)
101 		return 1;
102 	if (fwrite(buf, 1, (size_t)len, arg) != (size_t)len)
103 		return 0;
104 	return 1;
105 }
106 
107 typedef int char_io(void *arg, const void *buf, int len);
108 
109 /* This function handles display of
110  * strings, one character at a time.
111  * It is passed an unsigned long for each
112  * character because it could come from 2 or even
113  * 4 byte forms.
114  */
115 
116 static int
117 do_esc_char(unsigned long c, unsigned char flags, char *do_quotes,
118     char_io *io_ch, void *arg)
119 {
120 	unsigned char chflgs, chtmp;
121 	char tmphex[sizeof(long) * 2 + 3];
122 
123 	if (c > 0xffffffffL)
124 		return -1;
125 	if (c > 0xffff) {
126 		snprintf(tmphex, sizeof tmphex, "\\W%08lX", c);
127 		if (!io_ch(arg, tmphex, 10))
128 			return -1;
129 		return 10;
130 	}
131 	if (c > 0xff) {
132 		snprintf(tmphex, sizeof tmphex, "\\U%04lX", c);
133 		if (!io_ch(arg, tmphex, 6))
134 			return -1;
135 		return 6;
136 	}
137 	chtmp = (unsigned char)c;
138 	if (chtmp > 0x7f)
139 		chflgs = flags & ASN1_STRFLGS_ESC_MSB;
140 	else
141 		chflgs = char_type[chtmp] & flags;
142 	if (chflgs & CHARTYPE_BS_ESC) {
143 		/* If we don't escape with quotes, signal we need quotes */
144 		if (chflgs & ASN1_STRFLGS_ESC_QUOTE) {
145 			if (do_quotes)
146 				*do_quotes = 1;
147 			if (!io_ch(arg, &chtmp, 1))
148 				return -1;
149 			return 1;
150 		}
151 		if (!io_ch(arg, "\\", 1))
152 			return -1;
153 		if (!io_ch(arg, &chtmp, 1))
154 			return -1;
155 		return 2;
156 	}
157 	if (chflgs & (ASN1_STRFLGS_ESC_CTRL|ASN1_STRFLGS_ESC_MSB)) {
158 		snprintf(tmphex, sizeof tmphex, "\\%02X", chtmp);
159 		if (!io_ch(arg, tmphex, 3))
160 			return -1;
161 		return 3;
162 	}
163 	/* If we get this far and do any escaping at all must escape
164 	 * the escape character itself: backslash.
165 	 */
166 	if (chtmp == '\\' && flags & ESC_FLAGS) {
167 		if (!io_ch(arg, "\\\\", 2))
168 			return -1;
169 		return 2;
170 	}
171 	if (!io_ch(arg, &chtmp, 1))
172 		return -1;
173 	return 1;
174 }
175 
176 #define BUF_TYPE_WIDTH_MASK	0x7
177 #define BUF_TYPE_CONVUTF8	0x8
178 
179 /* This function sends each character in a buffer to
180  * do_esc_char(). It interprets the content formats
181  * and converts to or from UTF8 as appropriate.
182  */
183 
184 static int
185 do_buf(unsigned char *buf, int buflen, int type, unsigned char flags,
186     char *quotes, char_io *io_ch, void *arg)
187 {
188 	int i, outlen, len;
189 	unsigned char orflags, *p, *q;
190 	unsigned long c;
191 
192 	p = buf;
193 	q = buf + buflen;
194 	outlen = 0;
195 	while (p != q) {
196 		if (p == buf && flags & ASN1_STRFLGS_ESC_2253)
197 			orflags = CHARTYPE_FIRST_ESC_2253;
198 		else
199 			orflags = 0;
200 		switch (type & BUF_TYPE_WIDTH_MASK) {
201 		case 4:
202 			c = ((unsigned long)*p++) << 24;
203 			c |= ((unsigned long)*p++) << 16;
204 			c |= ((unsigned long)*p++) << 8;
205 			c |= *p++;
206 			if (c > UNICODE_MAX || UNICODE_IS_SURROGATE(c))
207 				return -1;
208 			break;
209 
210 		case 2:
211 			c = ((unsigned long)*p++) << 8;
212 			c |= *p++;
213 			if (UNICODE_IS_SURROGATE(c))
214 				return -1;
215 			break;
216 
217 		case 1:
218 			c = *p++;
219 			break;
220 
221 		case 0:
222 			i = UTF8_getc(p, q - p, &c);
223 			if (i < 0)
224 				return -1;	/* Invalid UTF8String */
225 			p += i;
226 			break;
227 		default:
228 			return -1;		/* invalid width */
229 		}
230 		if (p == q && flags & ASN1_STRFLGS_ESC_2253)
231 			orflags = CHARTYPE_LAST_ESC_2253;
232 		if (type & BUF_TYPE_CONVUTF8) {
233 			unsigned char utfbuf[6];
234 			int utflen;
235 
236 			utflen = UTF8_putc(utfbuf, sizeof utfbuf, c);
237 			if (utflen < 0)
238 				return -1;
239 			for (i = 0; i < utflen; i++) {
240 				/* We don't need to worry about setting orflags correctly
241 				 * because if utflen==1 its value will be correct anyway
242 				 * otherwise each character will be > 0x7f and so the
243 				 * character will never be escaped on first and last.
244 				 */
245 				len = do_esc_char(utfbuf[i],
246 				    (unsigned char)(flags | orflags), quotes,
247 				    io_ch, arg);
248 				if (len < 0)
249 					return -1;
250 				outlen += len;
251 			}
252 		} else {
253 			len = do_esc_char(c, (unsigned char)(flags | orflags),
254 			    quotes, io_ch, arg);
255 			if (len < 0)
256 				return -1;
257 			outlen += len;
258 		}
259 	}
260 	return outlen;
261 }
262 
263 /* This function hex dumps a buffer of characters */
264 
265 static int
266 do_hex_dump(char_io *io_ch, void *arg, unsigned char *buf, int buflen)
267 {
268 	static const char hexdig[] = "0123456789ABCDEF";
269 	unsigned char *p, *q;
270 	char hextmp[2];
271 	if (arg) {
272 		p = buf;
273 		q = buf + buflen;
274 		while (p != q) {
275 			hextmp[0] = hexdig[*p >> 4];
276 			hextmp[1] = hexdig[*p & 0xf];
277 			if (!io_ch(arg, hextmp, 2))
278 				return -1;
279 			p++;
280 		}
281 	}
282 	return buflen << 1;
283 }
284 
285 /* "dump" a string. This is done when the type is unknown,
286  * or the flags request it. We can either dump the content
287  * octets or the entire DER encoding. This uses the RFC2253
288  * #01234 format.
289  */
290 
291 static int
292 do_dump(unsigned long lflags, char_io *io_ch, void *arg, const ASN1_STRING *str)
293 {
294 	/* Placing the ASN1_STRING in a temp ASN1_TYPE allows
295 	 * the DER encoding to readily obtained
296 	 */
297 	ASN1_TYPE t;
298 	unsigned char *der_buf, *p;
299 	int outlen, der_len;
300 
301 	if (!io_ch(arg, "#", 1))
302 		return -1;
303 	/* If we don't dump DER encoding just dump content octets */
304 	if (!(lflags & ASN1_STRFLGS_DUMP_DER)) {
305 		outlen = do_hex_dump(io_ch, arg, str->data, str->length);
306 		if (outlen < 0)
307 			return -1;
308 		return outlen + 1;
309 	}
310 	t.type = str->type;
311 	t.value.ptr = (char *)str;
312 	der_len = i2d_ASN1_TYPE(&t, NULL);
313 	der_buf = malloc(der_len);
314 	if (!der_buf)
315 		return -1;
316 	p = der_buf;
317 	i2d_ASN1_TYPE(&t, &p);
318 	outlen = do_hex_dump(io_ch, arg, der_buf, der_len);
319 	free(der_buf);
320 	if (outlen < 0)
321 		return -1;
322 	return outlen + 1;
323 }
324 
325 /* Lookup table to convert tags to character widths,
326  * 0 = UTF8 encoded, -1 is used for non string types
327  * otherwise it is the number of bytes per character
328  */
329 
330 static const signed char tag2nbyte[] = {
331 	-1, -1, -1, -1, -1,	/* 0-4 */
332 	-1, -1, -1, -1, -1,	/* 5-9 */
333 	-1, -1, 0, -1,		/* 10-13 */
334 	-1, -1, -1, -1,		/* 15-17 */
335 	-1, 1, 1,		/* 18-20 */
336 	-1, 1, 1, 1,		/* 21-24 */
337 	-1, 1, -1,		/* 25-27 */
338 	4, -1, 2		/* 28-30 */
339 };
340 
341 /* This is the main function, print out an
342  * ASN1_STRING taking note of various escape
343  * and display options. Returns number of
344  * characters written or -1 if an error
345  * occurred.
346  */
347 
348 static int
349 do_print_ex(char_io *io_ch, void *arg, unsigned long lflags,
350     const ASN1_STRING *str)
351 {
352 	int outlen, len;
353 	int type;
354 	char quotes;
355 	unsigned char flags;
356 
357 	quotes = 0;
358 	/* Keep a copy of escape flags */
359 	flags = (unsigned char)(lflags & ESC_FLAGS);
360 	type = str->type;
361 	outlen = 0;
362 
363 	if (lflags & ASN1_STRFLGS_SHOW_TYPE) {
364 		const char *tagname;
365 		tagname = ASN1_tag2str(type);
366 		outlen += strlen(tagname);
367 		if (!io_ch(arg, tagname, outlen) || !io_ch(arg, ":", 1))
368 			return -1;
369 		outlen++;
370 	}
371 
372 	/* Decide what to do with type, either dump content or display it */
373 
374 	/* Dump everything */
375 	if (lflags & ASN1_STRFLGS_DUMP_ALL)
376 		type = -1;
377 	/* Ignore the string type */
378 	else if (lflags & ASN1_STRFLGS_IGNORE_TYPE)
379 		type = 1;
380 	else {
381 		/* Else determine width based on type */
382 		if ((type > 0) && (type < 31))
383 			type = tag2nbyte[type];
384 		else
385 			type = -1;
386 		if ((type == -1) && !(lflags & ASN1_STRFLGS_DUMP_UNKNOWN))
387 			type = 1;
388 	}
389 
390 	if (type == -1) {
391 		len = do_dump(lflags, io_ch, arg, str);
392 		if (len < 0)
393 			return -1;
394 		outlen += len;
395 		return outlen;
396 	}
397 
398 	if (lflags & ASN1_STRFLGS_UTF8_CONVERT) {
399 		/* Note: if string is UTF8 and we want
400 		 * to convert to UTF8 then we just interpret
401 		 * it as 1 byte per character to avoid converting
402 		 * twice.
403 		 */
404 		if (!type)
405 			type = 1;
406 		else
407 			type |= BUF_TYPE_CONVUTF8;
408 	}
409 
410 	len = do_buf(str->data, str->length, type, flags, &quotes, io_ch, NULL);
411 	if (len < 0)
412 		return -1;
413 	outlen += len;
414 	if (quotes)
415 		outlen += 2;
416 	if (!arg)
417 		return outlen;
418 	if (quotes && !io_ch(arg, "\"", 1))
419 		return -1;
420 	if (do_buf(str->data, str->length, type, flags, NULL, io_ch, arg) < 0)
421 		return -1;
422 	if (quotes && !io_ch(arg, "\"", 1))
423 		return -1;
424 	return outlen;
425 }
426 
427 /* Used for line indenting: print 'indent' spaces */
428 
429 static int
430 do_indent(char_io *io_ch, void *arg, int indent)
431 {
432 	int i;
433 	for (i = 0; i < indent; i++)
434 		if (!io_ch(arg, " ", 1))
435 			return 0;
436 	return 1;
437 }
438 
439 #define FN_WIDTH_LN	25
440 #define FN_WIDTH_SN	10
441 
442 static int
443 do_name_ex(char_io *io_ch, void *arg, const X509_NAME *n, int indent,
444     unsigned long flags)
445 {
446 	int i, prev = -1, orflags, cnt;
447 	int fn_opt, fn_nid;
448 	ASN1_OBJECT *fn;
449 	ASN1_STRING *val;
450 	X509_NAME_ENTRY *ent;
451 	char objtmp[80];
452 	const char *objbuf;
453 	int outlen, len;
454 	char *sep_dn, *sep_mv, *sep_eq;
455 	int sep_dn_len, sep_mv_len, sep_eq_len;
456 
457 	if (indent < 0)
458 		indent = 0;
459 	outlen = indent;
460 	if (!do_indent(io_ch, arg, indent))
461 		return -1;
462 
463 	switch (flags & XN_FLAG_SEP_MASK) {
464 	case XN_FLAG_SEP_MULTILINE:
465 		sep_dn = "\n";
466 		sep_dn_len = 1;
467 		sep_mv = " + ";
468 		sep_mv_len = 3;
469 		break;
470 
471 	case XN_FLAG_SEP_COMMA_PLUS:
472 		sep_dn = ",";
473 		sep_dn_len = 1;
474 		sep_mv = "+";
475 		sep_mv_len = 1;
476 		indent = 0;
477 		break;
478 
479 	case XN_FLAG_SEP_CPLUS_SPC:
480 		sep_dn = ", ";
481 		sep_dn_len = 2;
482 		sep_mv = " + ";
483 		sep_mv_len = 3;
484 		indent = 0;
485 		break;
486 
487 	case XN_FLAG_SEP_SPLUS_SPC:
488 		sep_dn = "; ";
489 		sep_dn_len = 2;
490 		sep_mv = " + ";
491 		sep_mv_len = 3;
492 		indent = 0;
493 		break;
494 
495 	default:
496 		return -1;
497 	}
498 
499 	if (flags & XN_FLAG_SPC_EQ) {
500 		sep_eq = " = ";
501 		sep_eq_len = 3;
502 	} else {
503 		sep_eq = "=";
504 		sep_eq_len = 1;
505 	}
506 
507 	fn_opt = flags & XN_FLAG_FN_MASK;
508 
509 	cnt = X509_NAME_entry_count(n);
510 	for (i = 0; i < cnt; i++) {
511 		if (flags & XN_FLAG_DN_REV)
512 			ent = X509_NAME_get_entry(n, cnt - i - 1);
513 		else
514 			ent = X509_NAME_get_entry(n, i);
515 		if (prev != -1) {
516 			if (prev == ent->set) {
517 				if (!io_ch(arg, sep_mv, sep_mv_len))
518 					return -1;
519 				outlen += sep_mv_len;
520 			} else {
521 				if (!io_ch(arg, sep_dn, sep_dn_len))
522 					return -1;
523 				outlen += sep_dn_len;
524 				if (!do_indent(io_ch, arg, indent))
525 					return -1;
526 				outlen += indent;
527 			}
528 		}
529 		prev = ent->set;
530 		fn = X509_NAME_ENTRY_get_object(ent);
531 		val = X509_NAME_ENTRY_get_data(ent);
532 		fn_nid = OBJ_obj2nid(fn);
533 		if (fn_opt != XN_FLAG_FN_NONE) {
534 			int objlen, fld_len;
535 			if ((fn_opt == XN_FLAG_FN_OID) ||
536 			    (fn_nid == NID_undef)) {
537 				OBJ_obj2txt(objtmp, sizeof objtmp, fn, 1);
538 				fld_len = 0; /* XXX: what should this be? */
539 				objbuf = objtmp;
540 			} else {
541 				if (fn_opt == XN_FLAG_FN_SN) {
542 					fld_len = FN_WIDTH_SN;
543 					objbuf = OBJ_nid2sn(fn_nid);
544 				} else if (fn_opt == XN_FLAG_FN_LN) {
545 					fld_len = FN_WIDTH_LN;
546 					objbuf = OBJ_nid2ln(fn_nid);
547 				} else {
548 					fld_len = 0; /* XXX: what should this be? */
549 					objbuf = "";
550 				}
551 			}
552 			objlen = strlen(objbuf);
553 			if (!io_ch(arg, objbuf, objlen))
554 				return -1;
555 			if ((objlen < fld_len) && (flags & XN_FLAG_FN_ALIGN)) {
556 				if (!do_indent(io_ch, arg, fld_len - objlen))
557 					return -1;
558 				outlen += fld_len - objlen;
559 			}
560 			if (!io_ch(arg, sep_eq, sep_eq_len))
561 				return -1;
562 			outlen += objlen + sep_eq_len;
563 		}
564 		/* If the field name is unknown then fix up the DER dump
565 		 * flag. We might want to limit this further so it will
566  		 * DER dump on anything other than a few 'standard' fields.
567 		 */
568 		if ((fn_nid == NID_undef) &&
569 		    (flags & XN_FLAG_DUMP_UNKNOWN_FIELDS))
570 			orflags = ASN1_STRFLGS_DUMP_ALL;
571 		else
572 			orflags = 0;
573 
574 		len = do_print_ex(io_ch, arg, flags | orflags, val);
575 		if (len < 0)
576 			return -1;
577 		outlen += len;
578 	}
579 	return outlen;
580 }
581 
582 /* Wrappers round the main functions */
583 
584 int
585 X509_NAME_print_ex(BIO *out, const X509_NAME *nm, int indent,
586     unsigned long flags)
587 {
588 	if (flags == XN_FLAG_COMPAT)
589 		return X509_NAME_print(out, nm, indent);
590 	return do_name_ex(send_bio_chars, out, nm, indent, flags);
591 }
592 
593 int
594 X509_NAME_print_ex_fp(FILE *fp, const X509_NAME *nm, int indent,
595     unsigned long flags)
596 {
597 	if (flags == XN_FLAG_COMPAT) {
598 		BIO *btmp;
599 		int ret;
600 		btmp = BIO_new_fp(fp, BIO_NOCLOSE);
601 		if (!btmp)
602 			return -1;
603 		ret = X509_NAME_print(btmp, nm, indent);
604 		BIO_free(btmp);
605 		return ret;
606 	}
607 	return do_name_ex(send_fp_chars, fp, nm, indent, flags);
608 }
609 
610 int
611 ASN1_STRING_print_ex(BIO *out, const ASN1_STRING *str, unsigned long flags)
612 {
613 	return do_print_ex(send_bio_chars, out, flags, str);
614 }
615 
616 int
617 ASN1_STRING_print_ex_fp(FILE *fp, const ASN1_STRING *str, unsigned long flags)
618 {
619 	return do_print_ex(send_fp_chars, fp, flags, str);
620 }
621 
622 /* Utility function: convert any string type to UTF8, returns number of bytes
623  * in output string or a negative error code
624  */
625 
626 int
627 ASN1_STRING_to_UTF8(unsigned char **out, const ASN1_STRING *in)
628 {
629 	ASN1_STRING stmp, *str = &stmp;
630 	int mbflag, type, ret;
631 
632 	if (!in)
633 		return -1;
634 	type = in->type;
635 	if ((type < 0) || (type > 30))
636 		return -1;
637 	mbflag = tag2nbyte[type];
638 	if (mbflag == -1)
639 		return -1;
640 	mbflag |= MBSTRING_FLAG;
641 	stmp.data = NULL;
642 	stmp.length = 0;
643 	ret = ASN1_mbstring_copy(&str, in->data, in->length, mbflag,
644 	    B_ASN1_UTF8STRING);
645 	if (ret < 0)
646 		return ret;
647 	*out = stmp.data;
648 	return stmp.length;
649 }
650