1 /*
2  * Copyright 2000-2018 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the OpenSSL license (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 #include <stdio.h>
11 #include <string.h>
12 #include "internal/cryptlib.h"
13 #include "crypto/asn1.h"
14 #include <openssl/crypto.h>
15 #include <openssl/x509.h>
16 #include <openssl/asn1.h>
17 
18 #include "charmap.h"
19 
20 /*
21  * ASN1_STRING_print_ex() and X509_NAME_print_ex(). Enhanced string and name
22  * printing routines handling multibyte characters, RFC2253 and a host of
23  * other options.
24  */
25 
26 #define CHARTYPE_BS_ESC         (ASN1_STRFLGS_ESC_2253 | CHARTYPE_FIRST_ESC_2253 | CHARTYPE_LAST_ESC_2253)
27 
28 #define ESC_FLAGS (ASN1_STRFLGS_ESC_2253 | \
29                   ASN1_STRFLGS_ESC_2254 | \
30                   ASN1_STRFLGS_ESC_QUOTE | \
31                   ASN1_STRFLGS_ESC_CTRL | \
32                   ASN1_STRFLGS_ESC_MSB)
33 
34 /*
35  * Three IO functions for sending data to memory, a BIO and and a FILE
36  * pointer.
37  */
send_bio_chars(void * arg,const void * buf,int len)38 static int send_bio_chars(void *arg, const void *buf, int len)
39 {
40     if (!arg)
41         return 1;
42     if (BIO_write(arg, buf, len) != len)
43         return 0;
44     return 1;
45 }
46 
47 #ifndef OPENSSL_NO_STDIO
send_fp_chars(void * arg,const void * buf,int len)48 static int send_fp_chars(void *arg, const void *buf, int len)
49 {
50     if (!arg)
51         return 1;
52     if (fwrite(buf, 1, len, arg) != (unsigned int)len)
53         return 0;
54     return 1;
55 }
56 #endif
57 
58 typedef int char_io (void *arg, const void *buf, int len);
59 
60 /*
61  * This function handles display of strings, one character at a time. It is
62  * passed an unsigned long for each character because it could come from 2 or
63  * even 4 byte forms.
64  */
65 
do_esc_char(unsigned long c,unsigned short flags,char * do_quotes,char_io * io_ch,void * arg)66 static int do_esc_char(unsigned long c, unsigned short flags, char *do_quotes,
67                        char_io *io_ch, void *arg)
68 {
69     unsigned short chflgs;
70     unsigned char chtmp;
71     char tmphex[HEX_SIZE(long) + 3];
72 
73     if (c > 0xffffffffL)
74         return -1;
75     if (c > 0xffff) {
76         BIO_snprintf(tmphex, sizeof(tmphex), "\\W%08lX", c);
77         if (!io_ch(arg, tmphex, 10))
78             return -1;
79         return 10;
80     }
81     if (c > 0xff) {
82         BIO_snprintf(tmphex, sizeof(tmphex), "\\U%04lX", c);
83         if (!io_ch(arg, tmphex, 6))
84             return -1;
85         return 6;
86     }
87     chtmp = (unsigned char)c;
88     if (chtmp > 0x7f)
89         chflgs = flags & ASN1_STRFLGS_ESC_MSB;
90     else
91         chflgs = char_type[chtmp] & flags;
92     if (chflgs & CHARTYPE_BS_ESC) {
93         /* If we don't escape with quotes, signal we need quotes */
94         if (chflgs & ASN1_STRFLGS_ESC_QUOTE) {
95             if (do_quotes)
96                 *do_quotes = 1;
97             if (!io_ch(arg, &chtmp, 1))
98                 return -1;
99             return 1;
100         }
101         if (!io_ch(arg, "\\", 1))
102             return -1;
103         if (!io_ch(arg, &chtmp, 1))
104             return -1;
105         return 2;
106     }
107     if (chflgs & (ASN1_STRFLGS_ESC_CTRL
108                   | ASN1_STRFLGS_ESC_MSB
109                   | ASN1_STRFLGS_ESC_2254)) {
110         BIO_snprintf(tmphex, 11, "\\%02X", chtmp);
111         if (!io_ch(arg, tmphex, 3))
112             return -1;
113         return 3;
114     }
115     /*
116      * If we get this far and do any escaping at all must escape the escape
117      * character itself: backslash.
118      */
119     if (chtmp == '\\' && (flags & ESC_FLAGS)) {
120         if (!io_ch(arg, "\\\\", 2))
121             return -1;
122         return 2;
123     }
124     if (!io_ch(arg, &chtmp, 1))
125         return -1;
126     return 1;
127 }
128 
129 #define BUF_TYPE_WIDTH_MASK     0x7
130 #define BUF_TYPE_CONVUTF8       0x8
131 
132 /*
133  * This function sends each character in a buffer to do_esc_char(). It
134  * interprets the content formats and converts to or from UTF8 as
135  * appropriate.
136  */
137 
do_buf(unsigned char * buf,int buflen,int type,unsigned short flags,char * quotes,char_io * io_ch,void * arg)138 static int do_buf(unsigned char *buf, int buflen,
139                   int type, unsigned short flags, char *quotes, char_io *io_ch,
140                   void *arg)
141 {
142     int i, outlen, len, charwidth;
143     unsigned short orflags;
144     unsigned char *p, *q;
145     unsigned long c;
146 
147     p = buf;
148     q = buf + buflen;
149     outlen = 0;
150     charwidth = type & BUF_TYPE_WIDTH_MASK;
151 
152     switch (charwidth) {
153     case 4:
154         if (buflen & 3) {
155             ASN1err(ASN1_F_DO_BUF, ASN1_R_INVALID_UNIVERSALSTRING_LENGTH);
156             return -1;
157         }
158         break;
159     case 2:
160         if (buflen & 1) {
161             ASN1err(ASN1_F_DO_BUF, ASN1_R_INVALID_BMPSTRING_LENGTH);
162             return -1;
163         }
164         break;
165     default:
166         break;
167     }
168 
169     while (p != q) {
170         if (p == buf && flags & ASN1_STRFLGS_ESC_2253)
171             orflags = CHARTYPE_FIRST_ESC_2253;
172         else
173             orflags = 0;
174 
175         switch (charwidth) {
176         case 4:
177             c = ((unsigned long)*p++) << 24;
178             c |= ((unsigned long)*p++) << 16;
179             c |= ((unsigned long)*p++) << 8;
180             c |= *p++;
181             break;
182 
183         case 2:
184             c = ((unsigned long)*p++) << 8;
185             c |= *p++;
186             break;
187 
188         case 1:
189             c = *p++;
190             break;
191 
192         case 0:
193             i = UTF8_getc(p, buflen, &c);
194             if (i < 0)
195                 return -1;      /* Invalid UTF8String */
196             buflen -= i;
197             p += i;
198             break;
199         default:
200             return -1;          /* invalid width */
201         }
202         if (p == q && flags & ASN1_STRFLGS_ESC_2253)
203             orflags = CHARTYPE_LAST_ESC_2253;
204         if (type & BUF_TYPE_CONVUTF8) {
205             unsigned char utfbuf[6];
206             int utflen;
207             utflen = UTF8_putc(utfbuf, sizeof(utfbuf), c);
208             for (i = 0; i < utflen; i++) {
209                 /*
210                  * We don't need to worry about setting orflags correctly
211                  * because if utflen==1 its value will be correct anyway
212                  * otherwise each character will be > 0x7f and so the
213                  * character will never be escaped on first and last.
214                  */
215                 len = do_esc_char(utfbuf[i], flags | orflags, quotes,
216                                   io_ch, arg);
217                 if (len < 0)
218                     return -1;
219                 outlen += len;
220             }
221         } else {
222             len = do_esc_char(c, flags | orflags, quotes,
223                               io_ch, arg);
224             if (len < 0)
225                 return -1;
226             outlen += len;
227         }
228     }
229     return outlen;
230 }
231 
232 /* This function hex dumps a buffer of characters */
233 
do_hex_dump(char_io * io_ch,void * arg,unsigned char * buf,int buflen)234 static int do_hex_dump(char_io *io_ch, void *arg, unsigned char *buf,
235                        int buflen)
236 {
237     static const char hexdig[] = "0123456789ABCDEF";
238     unsigned char *p, *q;
239     char hextmp[2];
240     if (arg) {
241         p = buf;
242         q = buf + buflen;
243         while (p != q) {
244             hextmp[0] = hexdig[*p >> 4];
245             hextmp[1] = hexdig[*p & 0xf];
246             if (!io_ch(arg, hextmp, 2))
247                 return -1;
248             p++;
249         }
250     }
251     return buflen << 1;
252 }
253 
254 /*
255  * "dump" a string. This is done when the type is unknown, or the flags
256  * request it. We can either dump the content octets or the entire DER
257  * encoding. This uses the RFC2253 #01234 format.
258  */
259 
do_dump(unsigned long lflags,char_io * io_ch,void * arg,const ASN1_STRING * str)260 static int do_dump(unsigned long lflags, char_io *io_ch, void *arg,
261                    const ASN1_STRING *str)
262 {
263     /*
264      * Placing the ASN1_STRING in a temp ASN1_TYPE allows the DER encoding to
265      * readily obtained
266      */
267     ASN1_TYPE t;
268     unsigned char *der_buf, *p;
269     int outlen, der_len;
270 
271     if (!io_ch(arg, "#", 1))
272         return -1;
273     /* If we don't dump DER encoding just dump content octets */
274     if (!(lflags & ASN1_STRFLGS_DUMP_DER)) {
275         outlen = do_hex_dump(io_ch, arg, str->data, str->length);
276         if (outlen < 0)
277             return -1;
278         return outlen + 1;
279     }
280     t.type = str->type;
281     t.value.ptr = (char *)str;
282     der_len = i2d_ASN1_TYPE(&t, NULL);
283     if ((der_buf = OPENSSL_malloc(der_len)) == NULL) {
284         ASN1err(ASN1_F_DO_DUMP, ERR_R_MALLOC_FAILURE);
285         return -1;
286     }
287     p = der_buf;
288     i2d_ASN1_TYPE(&t, &p);
289     outlen = do_hex_dump(io_ch, arg, der_buf, der_len);
290     OPENSSL_free(der_buf);
291     if (outlen < 0)
292         return -1;
293     return outlen + 1;
294 }
295 
296 /*
297  * Lookup table to convert tags to character widths, 0 = UTF8 encoded, -1 is
298  * used for non string types otherwise it is the number of bytes per
299  * character
300  */
301 
302 static const signed char tag2nbyte[] = {
303     -1, -1, -1, -1, -1,         /* 0-4 */
304     -1, -1, -1, -1, -1,         /* 5-9 */
305     -1, -1,                     /* 10-11 */
306      0,                         /* 12 V_ASN1_UTF8STRING */
307     -1, -1, -1, -1, -1,         /* 13-17 */
308      1,                         /* 18 V_ASN1_NUMERICSTRING */
309      1,                         /* 19 V_ASN1_PRINTABLESTRING */
310      1,                         /* 20 V_ASN1_T61STRING */
311     -1,                         /* 21 */
312      1,                         /* 22 V_ASN1_IA5STRING */
313      1,                         /* 23 V_ASN1_UTCTIME */
314      1,                         /* 24 V_ASN1_GENERALIZEDTIME */
315     -1,                         /* 25 */
316      1,                         /* 26 V_ASN1_ISO64STRING */
317     -1,                         /* 27 */
318      4,                         /* 28 V_ASN1_UNIVERSALSTRING */
319     -1,                         /* 29 */
320      2                          /* 30 V_ASN1_BMPSTRING */
321 };
322 
323 /*
324  * This is the main function, print out an ASN1_STRING taking note of various
325  * escape and display options. Returns number of characters written or -1 if
326  * an error occurred.
327  */
328 
do_print_ex(char_io * io_ch,void * arg,unsigned long lflags,const ASN1_STRING * str)329 static int do_print_ex(char_io *io_ch, void *arg, unsigned long lflags,
330                        const ASN1_STRING *str)
331 {
332     int outlen, len;
333     int type;
334     char quotes;
335     unsigned short flags;
336     quotes = 0;
337     /* Keep a copy of escape flags */
338     flags = (unsigned short)(lflags & ESC_FLAGS);
339 
340     type = str->type;
341 
342     outlen = 0;
343 
344     if (lflags & ASN1_STRFLGS_SHOW_TYPE) {
345         const char *tagname;
346         tagname = ASN1_tag2str(type);
347         outlen += strlen(tagname);
348         if (!io_ch(arg, tagname, outlen) || !io_ch(arg, ":", 1))
349             return -1;
350         outlen++;
351     }
352 
353     /* Decide what to do with type, either dump content or display it */
354 
355     /* Dump everything */
356     if (lflags & ASN1_STRFLGS_DUMP_ALL)
357         type = -1;
358     /* Ignore the string type */
359     else if (lflags & ASN1_STRFLGS_IGNORE_TYPE)
360         type = 1;
361     else {
362         /* Else determine width based on type */
363         if ((type > 0) && (type < 31))
364             type = tag2nbyte[type];
365         else
366             type = -1;
367         if ((type == -1) && !(lflags & ASN1_STRFLGS_DUMP_UNKNOWN))
368             type = 1;
369     }
370 
371     if (type == -1) {
372         len = do_dump(lflags, io_ch, arg, str);
373         if (len < 0)
374             return -1;
375         outlen += len;
376         return outlen;
377     }
378 
379     if (lflags & ASN1_STRFLGS_UTF8_CONVERT) {
380         /*
381          * Note: if string is UTF8 and we want to convert to UTF8 then we
382          * just interpret it as 1 byte per character to avoid converting
383          * twice.
384          */
385         if (!type)
386             type = 1;
387         else
388             type |= BUF_TYPE_CONVUTF8;
389     }
390 
391     len = do_buf(str->data, str->length, type, flags, &quotes, io_ch, NULL);
392     if (len < 0)
393         return -1;
394     outlen += len;
395     if (quotes)
396         outlen += 2;
397     if (!arg)
398         return outlen;
399     if (quotes && !io_ch(arg, "\"", 1))
400         return -1;
401     if (do_buf(str->data, str->length, type, flags, NULL, io_ch, arg) < 0)
402         return -1;
403     if (quotes && !io_ch(arg, "\"", 1))
404         return -1;
405     return outlen;
406 }
407 
408 /* Used for line indenting: print 'indent' spaces */
409 
do_indent(char_io * io_ch,void * arg,int indent)410 static int do_indent(char_io *io_ch, void *arg, int indent)
411 {
412     int i;
413     for (i = 0; i < indent; i++)
414         if (!io_ch(arg, " ", 1))
415             return 0;
416     return 1;
417 }
418 
419 #define FN_WIDTH_LN     25
420 #define FN_WIDTH_SN     10
421 
do_name_ex(char_io * io_ch,void * arg,const X509_NAME * n,int indent,unsigned long flags)422 static int do_name_ex(char_io *io_ch, void *arg, const X509_NAME *n,
423                       int indent, unsigned long flags)
424 {
425     int i, prev = -1, orflags, cnt;
426     int fn_opt, fn_nid;
427     ASN1_OBJECT *fn;
428     const ASN1_STRING *val;
429     const X509_NAME_ENTRY *ent;
430     char objtmp[80];
431     const char *objbuf;
432     int outlen, len;
433     char *sep_dn, *sep_mv, *sep_eq;
434     int sep_dn_len, sep_mv_len, sep_eq_len;
435     if (indent < 0)
436         indent = 0;
437     outlen = indent;
438     if (!do_indent(io_ch, arg, indent))
439         return -1;
440     switch (flags & XN_FLAG_SEP_MASK) {
441     case XN_FLAG_SEP_MULTILINE:
442         sep_dn = "\n";
443         sep_dn_len = 1;
444         sep_mv = " + ";
445         sep_mv_len = 3;
446         break;
447 
448     case XN_FLAG_SEP_COMMA_PLUS:
449         sep_dn = ",";
450         sep_dn_len = 1;
451         sep_mv = "+";
452         sep_mv_len = 1;
453         indent = 0;
454         break;
455 
456     case XN_FLAG_SEP_CPLUS_SPC:
457         sep_dn = ", ";
458         sep_dn_len = 2;
459         sep_mv = " + ";
460         sep_mv_len = 3;
461         indent = 0;
462         break;
463 
464     case XN_FLAG_SEP_SPLUS_SPC:
465         sep_dn = "; ";
466         sep_dn_len = 2;
467         sep_mv = " + ";
468         sep_mv_len = 3;
469         indent = 0;
470         break;
471 
472     default:
473         return -1;
474     }
475 
476     if (flags & XN_FLAG_SPC_EQ) {
477         sep_eq = " = ";
478         sep_eq_len = 3;
479     } else {
480         sep_eq = "=";
481         sep_eq_len = 1;
482     }
483 
484     fn_opt = flags & XN_FLAG_FN_MASK;
485 
486     cnt = X509_NAME_entry_count(n);
487     for (i = 0; i < cnt; i++) {
488         if (flags & XN_FLAG_DN_REV)
489             ent = X509_NAME_get_entry(n, cnt - i - 1);
490         else
491             ent = X509_NAME_get_entry(n, i);
492         if (prev != -1) {
493             if (prev == X509_NAME_ENTRY_set(ent)) {
494                 if (!io_ch(arg, sep_mv, sep_mv_len))
495                     return -1;
496                 outlen += sep_mv_len;
497             } else {
498                 if (!io_ch(arg, sep_dn, sep_dn_len))
499                     return -1;
500                 outlen += sep_dn_len;
501                 if (!do_indent(io_ch, arg, indent))
502                     return -1;
503                 outlen += indent;
504             }
505         }
506         prev = X509_NAME_ENTRY_set(ent);
507         fn = X509_NAME_ENTRY_get_object(ent);
508         val = X509_NAME_ENTRY_get_data(ent);
509         fn_nid = OBJ_obj2nid(fn);
510         if (fn_opt != XN_FLAG_FN_NONE) {
511             int objlen, fld_len;
512             if ((fn_opt == XN_FLAG_FN_OID) || (fn_nid == NID_undef)) {
513                 OBJ_obj2txt(objtmp, sizeof(objtmp), fn, 1);
514                 fld_len = 0;    /* XXX: what should this be? */
515                 objbuf = objtmp;
516             } else {
517                 if (fn_opt == XN_FLAG_FN_SN) {
518                     fld_len = FN_WIDTH_SN;
519                     objbuf = OBJ_nid2sn(fn_nid);
520                 } else if (fn_opt == XN_FLAG_FN_LN) {
521                     fld_len = FN_WIDTH_LN;
522                     objbuf = OBJ_nid2ln(fn_nid);
523                 } else {
524                     fld_len = 0; /* XXX: what should this be? */
525                     objbuf = "";
526                 }
527             }
528             objlen = strlen(objbuf);
529             if (!io_ch(arg, objbuf, objlen))
530                 return -1;
531             if ((objlen < fld_len) && (flags & XN_FLAG_FN_ALIGN)) {
532                 if (!do_indent(io_ch, arg, fld_len - objlen))
533                     return -1;
534                 outlen += fld_len - objlen;
535             }
536             if (!io_ch(arg, sep_eq, sep_eq_len))
537                 return -1;
538             outlen += objlen + sep_eq_len;
539         }
540         /*
541          * If the field name is unknown then fix up the DER dump flag. We
542          * might want to limit this further so it will DER dump on anything
543          * other than a few 'standard' fields.
544          */
545         if ((fn_nid == NID_undef) && (flags & XN_FLAG_DUMP_UNKNOWN_FIELDS))
546             orflags = ASN1_STRFLGS_DUMP_ALL;
547         else
548             orflags = 0;
549 
550         len = do_print_ex(io_ch, arg, flags | orflags, val);
551         if (len < 0)
552             return -1;
553         outlen += len;
554     }
555     return outlen;
556 }
557 
558 /* Wrappers round the main functions */
559 
X509_NAME_print_ex(BIO * out,const X509_NAME * nm,int indent,unsigned long flags)560 int X509_NAME_print_ex(BIO *out, const X509_NAME *nm, int indent,
561                        unsigned long flags)
562 {
563     if (flags == XN_FLAG_COMPAT)
564         return X509_NAME_print(out, nm, indent);
565     return do_name_ex(send_bio_chars, out, nm, indent, flags);
566 }
567 
568 #ifndef OPENSSL_NO_STDIO
X509_NAME_print_ex_fp(FILE * fp,const X509_NAME * nm,int indent,unsigned long flags)569 int X509_NAME_print_ex_fp(FILE *fp, const X509_NAME *nm, int indent,
570                           unsigned long flags)
571 {
572     if (flags == XN_FLAG_COMPAT) {
573         BIO *btmp;
574         int ret;
575         btmp = BIO_new_fp(fp, BIO_NOCLOSE);
576         if (!btmp)
577             return -1;
578         ret = X509_NAME_print(btmp, nm, indent);
579         BIO_free(btmp);
580         return ret;
581     }
582     return do_name_ex(send_fp_chars, fp, nm, indent, flags);
583 }
584 #endif
585 
ASN1_STRING_print_ex(BIO * out,const ASN1_STRING * str,unsigned long flags)586 int ASN1_STRING_print_ex(BIO *out, const ASN1_STRING *str, unsigned long flags)
587 {
588     return do_print_ex(send_bio_chars, out, flags, str);
589 }
590 
591 #ifndef OPENSSL_NO_STDIO
ASN1_STRING_print_ex_fp(FILE * fp,const ASN1_STRING * str,unsigned long flags)592 int ASN1_STRING_print_ex_fp(FILE *fp, const ASN1_STRING *str, unsigned long flags)
593 {
594     return do_print_ex(send_fp_chars, fp, flags, str);
595 }
596 #endif
597 
598 /*
599  * Utility function: convert any string type to UTF8, returns number of bytes
600  * in output string or a negative error code
601  */
602 
ASN1_STRING_to_UTF8(unsigned char ** out,const ASN1_STRING * in)603 int ASN1_STRING_to_UTF8(unsigned char **out, const ASN1_STRING *in)
604 {
605     ASN1_STRING stmp, *str = &stmp;
606     int mbflag, type, ret;
607     if (!in)
608         return -1;
609     type = in->type;
610     if ((type < 0) || (type > 30))
611         return -1;
612     mbflag = tag2nbyte[type];
613     if (mbflag == -1)
614         return -1;
615     mbflag |= MBSTRING_FLAG;
616     stmp.data = NULL;
617     stmp.length = 0;
618     stmp.flags = 0;
619     ret =
620         ASN1_mbstring_copy(&str, in->data, in->length, mbflag,
621                            B_ASN1_UTF8STRING);
622     if (ret < 0)
623         return ret;
624     *out = stmp.data;
625     return stmp.length;
626 }
627