xref: /openssl/crypto/asn1/a_mbstr.c (revision 33847508)
1 /*
2  * Copyright 1999-2021 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (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 "crypto/ctype.h"
12 #include "internal/cryptlib.h"
13 #include "internal/unicode.h"
14 #include <openssl/asn1.h>
15 
16 static int traverse_string(const unsigned char *p, int len, int inform,
17                            int (*rfunc) (unsigned long value, void *in),
18                            void *arg);
19 static int in_utf8(unsigned long value, void *arg);
20 static int out_utf8(unsigned long value, void *arg);
21 static int type_str(unsigned long value, void *arg);
22 static int cpy_asc(unsigned long value, void *arg);
23 static int cpy_bmp(unsigned long value, void *arg);
24 static int cpy_univ(unsigned long value, void *arg);
25 static int cpy_utf8(unsigned long value, void *arg);
26 
27 /*
28  * These functions take a string in UTF8, ASCII or multibyte form and a mask
29  * of permissible ASN1 string types. It then works out the minimal type
30  * (using the order Numeric < Printable < IA5 < T61 < BMP < Universal < UTF8)
31  * and creates a string of the correct type with the supplied data. Yes this is
32  * horrible: it has to be :-( The 'ncopy' form checks minimum and maximum
33  * size limits too.
34  */
35 
ASN1_mbstring_copy(ASN1_STRING ** out,const unsigned char * in,int len,int inform,unsigned long mask)36 int ASN1_mbstring_copy(ASN1_STRING **out, const unsigned char *in, int len,
37                        int inform, unsigned long mask)
38 {
39     return ASN1_mbstring_ncopy(out, in, len, inform, mask, 0, 0);
40 }
41 
ASN1_mbstring_ncopy(ASN1_STRING ** out,const unsigned char * in,int len,int inform,unsigned long mask,long minsize,long maxsize)42 int ASN1_mbstring_ncopy(ASN1_STRING **out, const unsigned char *in, int len,
43                         int inform, unsigned long mask,
44                         long minsize, long maxsize)
45 {
46     int str_type;
47     int ret;
48     char free_out;
49     int outform, outlen = 0;
50     ASN1_STRING *dest;
51     unsigned char *p;
52     int nchar;
53     int (*cpyfunc) (unsigned long, void *) = NULL;
54     if (len == -1)
55         len = strlen((const char *)in);
56     if (!mask)
57         mask = DIRSTRING_TYPE;
58     if (len < 0)
59         return -1;
60 
61     /* First do a string check and work out the number of characters */
62     switch (inform) {
63 
64     case MBSTRING_BMP:
65         if (len & 1) {
66             ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_BMPSTRING_LENGTH);
67             return -1;
68         }
69         nchar = len >> 1;
70         break;
71 
72     case MBSTRING_UNIV:
73         if (len & 3) {
74             ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_UNIVERSALSTRING_LENGTH);
75             return -1;
76         }
77         nchar = len >> 2;
78         break;
79 
80     case MBSTRING_UTF8:
81         nchar = 0;
82         /* This counts the characters and does utf8 syntax checking */
83         ret = traverse_string(in, len, MBSTRING_UTF8, in_utf8, &nchar);
84         if (ret < 0) {
85             ERR_raise(ERR_LIB_ASN1, ASN1_R_INVALID_UTF8STRING);
86             return -1;
87         }
88         break;
89 
90     case MBSTRING_ASC:
91         nchar = len;
92         break;
93 
94     default:
95         ERR_raise(ERR_LIB_ASN1, ASN1_R_UNKNOWN_FORMAT);
96         return -1;
97     }
98 
99     if ((minsize > 0) && (nchar < minsize)) {
100         ERR_raise_data(ERR_LIB_ASN1, ASN1_R_STRING_TOO_SHORT,
101                        "minsize=%ld", minsize);
102         return -1;
103     }
104 
105     if ((maxsize > 0) && (nchar > maxsize)) {
106         ERR_raise_data(ERR_LIB_ASN1, ASN1_R_STRING_TOO_LONG,
107                        "maxsize=%ld", maxsize);
108         return -1;
109     }
110 
111     /* Now work out minimal type (if any) */
112     if (traverse_string(in, len, inform, type_str, &mask) < 0) {
113         ERR_raise(ERR_LIB_ASN1, ASN1_R_ILLEGAL_CHARACTERS);
114         return -1;
115     }
116 
117     /* Now work out output format and string type */
118     outform = MBSTRING_ASC;
119     if (mask & B_ASN1_NUMERICSTRING)
120         str_type = V_ASN1_NUMERICSTRING;
121     else if (mask & B_ASN1_PRINTABLESTRING)
122         str_type = V_ASN1_PRINTABLESTRING;
123     else if (mask & B_ASN1_IA5STRING)
124         str_type = V_ASN1_IA5STRING;
125     else if (mask & B_ASN1_T61STRING)
126         str_type = V_ASN1_T61STRING;
127     else if (mask & B_ASN1_BMPSTRING) {
128         str_type = V_ASN1_BMPSTRING;
129         outform = MBSTRING_BMP;
130     } else if (mask & B_ASN1_UNIVERSALSTRING) {
131         str_type = V_ASN1_UNIVERSALSTRING;
132         outform = MBSTRING_UNIV;
133     } else {
134         str_type = V_ASN1_UTF8STRING;
135         outform = MBSTRING_UTF8;
136     }
137     if (!out)
138         return str_type;
139     if (*out) {
140         free_out = 0;
141         dest = *out;
142         ASN1_STRING_set0(dest,  NULL, 0);
143         dest->type = str_type;
144     } else {
145         free_out = 1;
146         dest = ASN1_STRING_type_new(str_type);
147         if (dest == NULL) {
148             ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
149             return -1;
150         }
151         *out = dest;
152     }
153     /* If both the same type just copy across */
154     if (inform == outform) {
155         if (!ASN1_STRING_set(dest, in, len)) {
156             ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
157             return -1;
158         }
159         return str_type;
160     }
161 
162     /* Work out how much space the destination will need */
163     switch (outform) {
164     case MBSTRING_ASC:
165         outlen = nchar;
166         cpyfunc = cpy_asc;
167         break;
168 
169     case MBSTRING_BMP:
170         outlen = nchar << 1;
171         cpyfunc = cpy_bmp;
172         break;
173 
174     case MBSTRING_UNIV:
175         outlen = nchar << 2;
176         cpyfunc = cpy_univ;
177         break;
178 
179     case MBSTRING_UTF8:
180         outlen = 0;
181         traverse_string(in, len, inform, out_utf8, &outlen);
182         cpyfunc = cpy_utf8;
183         break;
184     }
185     if ((p = OPENSSL_malloc(outlen + 1)) == NULL) {
186         if (free_out)
187             ASN1_STRING_free(dest);
188         ERR_raise(ERR_LIB_ASN1, ERR_R_MALLOC_FAILURE);
189         return -1;
190     }
191     dest->length = outlen;
192     dest->data = p;
193     p[outlen] = 0;
194     traverse_string(in, len, inform, cpyfunc, &p);
195     return str_type;
196 }
197 
198 /*
199  * This function traverses a string and passes the value of each character to
200  * an optional function along with a void * argument.
201  */
202 
traverse_string(const unsigned char * p,int len,int inform,int (* rfunc)(unsigned long value,void * in),void * arg)203 static int traverse_string(const unsigned char *p, int len, int inform,
204                            int (*rfunc) (unsigned long value, void *in),
205                            void *arg)
206 {
207     unsigned long value;
208     int ret;
209     while (len) {
210         if (inform == MBSTRING_ASC) {
211             value = *p++;
212             len--;
213         } else if (inform == MBSTRING_BMP) {
214             value = *p++ << 8;
215             value |= *p++;
216             len -= 2;
217         } else if (inform == MBSTRING_UNIV) {
218             value = ((unsigned long)*p++) << 24;
219             value |= ((unsigned long)*p++) << 16;
220             value |= *p++ << 8;
221             value |= *p++;
222             len -= 4;
223         } else {
224             ret = UTF8_getc(p, len, &value);
225             if (ret < 0)
226                 return -1;
227             len -= ret;
228             p += ret;
229         }
230         if (rfunc) {
231             ret = rfunc(value, arg);
232             if (ret <= 0)
233                 return ret;
234         }
235     }
236     return 1;
237 }
238 
239 /* Various utility functions for traverse_string */
240 
241 /* Just count number of characters */
242 
in_utf8(unsigned long value,void * arg)243 static int in_utf8(unsigned long value, void *arg)
244 {
245     int *nchar;
246 
247     if (!is_unicode_valid(value))
248         return -2;
249     nchar = arg;
250     (*nchar)++;
251     return 1;
252 }
253 
254 /* Determine size of output as a UTF8 String */
255 
out_utf8(unsigned long value,void * arg)256 static int out_utf8(unsigned long value, void *arg)
257 {
258     int *outlen, len;
259 
260     len = UTF8_putc(NULL, -1, value);
261     if (len <= 0)
262         return len;
263     outlen = arg;
264     *outlen += len;
265     return 1;
266 }
267 
268 /*
269  * Determine the "type" of a string: check each character against a supplied
270  * "mask".
271  */
272 
type_str(unsigned long value,void * arg)273 static int type_str(unsigned long value, void *arg)
274 {
275     unsigned long types = *((unsigned long *)arg);
276     const int native = value > INT_MAX ? INT_MAX : ossl_fromascii(value);
277 
278     if ((types & B_ASN1_NUMERICSTRING) && !(ossl_isdigit(native)
279                                             || native == ' '))
280         types &= ~B_ASN1_NUMERICSTRING;
281     if ((types & B_ASN1_PRINTABLESTRING) && !ossl_isasn1print(native))
282         types &= ~B_ASN1_PRINTABLESTRING;
283     if ((types & B_ASN1_IA5STRING) && !ossl_isascii(native))
284         types &= ~B_ASN1_IA5STRING;
285     if ((types & B_ASN1_T61STRING) && (value > 0xff))
286         types &= ~B_ASN1_T61STRING;
287     if ((types & B_ASN1_BMPSTRING) && (value > 0xffff))
288         types &= ~B_ASN1_BMPSTRING;
289     if ((types & B_ASN1_UTF8STRING) && !is_unicode_valid(value))
290         types &= ~B_ASN1_UTF8STRING;
291     if (!types)
292         return -1;
293     *((unsigned long *)arg) = types;
294     return 1;
295 }
296 
297 /* Copy one byte per character ASCII like strings */
298 
cpy_asc(unsigned long value,void * arg)299 static int cpy_asc(unsigned long value, void *arg)
300 {
301     unsigned char **p, *q;
302     p = arg;
303     q = *p;
304     *q = (unsigned char)value;
305     (*p)++;
306     return 1;
307 }
308 
309 /* Copy two byte per character BMPStrings */
310 
cpy_bmp(unsigned long value,void * arg)311 static int cpy_bmp(unsigned long value, void *arg)
312 {
313     unsigned char **p, *q;
314     p = arg;
315     q = *p;
316     *q++ = (unsigned char)((value >> 8) & 0xff);
317     *q = (unsigned char)(value & 0xff);
318     *p += 2;
319     return 1;
320 }
321 
322 /* Copy four byte per character UniversalStrings */
323 
cpy_univ(unsigned long value,void * arg)324 static int cpy_univ(unsigned long value, void *arg)
325 {
326     unsigned char **p, *q;
327     p = arg;
328     q = *p;
329     *q++ = (unsigned char)((value >> 24) & 0xff);
330     *q++ = (unsigned char)((value >> 16) & 0xff);
331     *q++ = (unsigned char)((value >> 8) & 0xff);
332     *q = (unsigned char)(value & 0xff);
333     *p += 4;
334     return 1;
335 }
336 
337 /* Copy to a UTF8String */
338 
cpy_utf8(unsigned long value,void * arg)339 static int cpy_utf8(unsigned long value, void *arg)
340 {
341     unsigned char **p;
342     int ret;
343     p = arg;
344     /* We already know there is enough room so pass 0xff as the length */
345     ret = UTF8_putc(*p, 0xff, value);
346     *p += ret;
347     return 1;
348 }
349