2 * Copyright (c) 1997 - 2007 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
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27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 RCSID("$Id: der_get.c 21369 2007-06-27 10:14:39Z lha $");
41 * All decoding functions take a pointer `p' to first position in
42 * which to read, from the left, `len' which means the maximum number
43 * of characters we are able to read, `ret' were the value will be
44 * returned and `size' where the number of used bytes is stored.
45 * Either 0 or an error code is returned.
49 der_get_unsigned (const unsigned char *p, size_t len,
50 unsigned *ret, size_t *size)
55 if (len == sizeof(unsigned) + 1 && p[0] == 0)
57 else if (len > sizeof(unsigned))
61 val = val * 256 + *p++;
63 if(size) *size = oldlen;
68 der_get_integer (const unsigned char *p, size_t len,
69 int *ret, size_t *size)
74 if (len > sizeof(int))
78 val = (signed char)*p++;
80 val = val * 256 + *p++;
83 if(size) *size = oldlen;
88 der_get_length (const unsigned char *p, size_t len,
89 size_t *val, size_t *size)
106 *val = ASN1_INDEFINITE;
113 e = der_get_unsigned (p, v, &tmp, &l);
116 if(size) *size = l + 1;
122 der_get_boolean(const unsigned char *p, size_t len, int *data, size_t *size)
135 der_get_general_string (const unsigned char *p, size_t len,
136 heim_general_string *str, size_t *size)
138 const unsigned char *p1;
141 p1 = memchr(p, 0, len);
144 * Allow trailing NULs. We allow this since MIT Kerberos sends
145 * an strings in the NEED_PREAUTH case that includes a
148 while (p1 - p < len && *p1 == '\0')
151 return ASN1_BAD_CHARACTER;
154 return ASN1_BAD_LENGTH;
156 s = malloc (len + 1);
162 if(size) *size = len;
167 der_get_utf8string (const unsigned char *p, size_t len,
168 heim_utf8_string *str, size_t *size)
170 return der_get_general_string(p, len, str, size);
174 der_get_printable_string (const unsigned char *p, size_t len,
175 heim_printable_string *str, size_t *size)
177 return der_get_general_string(p, len, str, size);
181 der_get_ia5_string (const unsigned char *p, size_t len,
182 heim_ia5_string *str, size_t *size)
184 return der_get_general_string(p, len, str, size);
188 der_get_bmp_string (const unsigned char *p, size_t len,
189 heim_bmp_string *data, size_t *size)
194 return ASN1_BAD_FORMAT;
195 data->length = len / 2;
196 if (data->length > UINT_MAX/sizeof(data->data[0]))
198 data->data = malloc(data->length * sizeof(data->data[0]));
199 if (data->data == NULL && data->length != 0)
202 for (i = 0; i < data->length; i++) {
203 data->data[i] = (p[0] << 8) | p[1];
206 if (size) *size = len;
212 der_get_universal_string (const unsigned char *p, size_t len,
213 heim_universal_string *data, size_t *size)
218 return ASN1_BAD_FORMAT;
219 data->length = len / 4;
220 if (data->length > UINT_MAX/sizeof(data->data[0]))
222 data->data = malloc(data->length * sizeof(data->data[0]));
223 if (data->data == NULL && data->length != 0)
226 for (i = 0; i < data->length; i++) {
227 data->data[i] = (p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3];
230 if (size) *size = len;
235 der_get_visible_string (const unsigned char *p, size_t len,
236 heim_visible_string *str, size_t *size)
238 return der_get_general_string(p, len, str, size);
242 der_get_octet_string (const unsigned char *p, size_t len,
243 heim_octet_string *data, size_t *size)
246 data->data = malloc(len);
247 if (data->data == NULL && data->length != 0)
249 memcpy (data->data, p, len);
250 if(size) *size = len;
255 der_get_heim_integer (const unsigned char *p, size_t len,
256 heim_integer *data, size_t *size)
278 data->data = malloc(data->length);
279 if (data->data == NULL) {
285 q = &((unsigned char*)data->data)[data->length - 1];
286 p += data->length - 1;
287 while (q >= (unsigned char*)data->data) {
302 data->data = malloc(data->length);
303 if (data->data == NULL && data->length != 0) {
309 memcpy(data->data, p, data->length);
317 generalizedtime2time (const char *s, time_t *t)
321 memset(&tm, 0, sizeof(tm));
322 if (sscanf (s, "%04d%02d%02d%02d%02d%02dZ",
323 &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &tm.tm_hour,
324 &tm.tm_min, &tm.tm_sec) != 6) {
325 if (sscanf (s, "%02d%02d%02d%02d%02d%02dZ",
326 &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &tm.tm_hour,
327 &tm.tm_min, &tm.tm_sec) != 6)
328 return ASN1_BAD_TIMEFORMAT;
336 *t = _der_timegm (&tm);
341 der_get_time (const unsigned char *p, size_t len,
342 time_t *data, size_t *size)
347 if (len > len + 1 || len == 0)
348 return ASN1_BAD_LENGTH;
350 times = malloc(len + 1);
353 memcpy(times, p, len);
355 e = generalizedtime2time(times, data);
357 if(size) *size = len;
362 der_get_generalized_time (const unsigned char *p, size_t len,
363 time_t *data, size_t *size)
365 return der_get_time(p, len, data, size);
369 der_get_utctime (const unsigned char *p, size_t len,
370 time_t *data, size_t *size)
372 return der_get_time(p, len, data, size);
376 der_get_oid (const unsigned char *p, size_t len,
377 heim_oid *data, size_t *size)
386 return ASN1_BAD_LENGTH;
388 if (len + 1 > UINT_MAX/sizeof(data->components[0]))
391 data->components = malloc((len + 1) * sizeof(data->components[0]));
392 if (data->components == NULL)
394 data->components[0] = (*p) / 40;
395 data->components[1] = (*p) % 40;
398 for (n = 2; len > 0; ++n) {
403 u1 = u * 128 + (*p++ % 128);
404 /* check that we don't overflow the element */
410 } while (len > 0 && p[-1] & 0x80);
411 data->components[n] = u;
413 if (n > 2 && p[-1] & 0x80) {
424 der_get_tag (const unsigned char *p, size_t len,
425 Der_class *class, Der_type *type,
426 unsigned int *tag, size_t *size)
431 *class = (Der_class)(((*p) >> 6) & 0x03);
432 *type = (Der_type)(((*p) >> 5) & 0x01);
436 unsigned int continuation;
442 continuation = *p & 128;
443 tag1 = *tag * 128 + (*p % 128);
444 /* check that we don't overflow the tag */
446 return ASN1_OVERFLOW;
449 } while(continuation);
451 if(size) *size = ret;
456 der_match_tag (const unsigned char *p, size_t len,
457 Der_class class, Der_type type,
458 unsigned int tag, size_t *size)
463 unsigned int thistag;
466 e = der_get_tag (p, len, &thisclass, &thistype, &thistag, &l);
468 if (class != thisclass || type != thistype)
471 return ASN1_MISPLACED_FIELD;
473 return ASN1_MISSING_FIELD;
479 der_match_tag_and_length (const unsigned char *p, size_t len,
480 Der_class class, Der_type type, unsigned int tag,
481 size_t *length_ret, size_t *size)
486 e = der_match_tag (p, len, class, type, tag, &l);
491 e = der_get_length (p, len, length_ret, &l);
496 if(size) *size = ret;
501 * Old versions of DCE was based on a very early beta of the MIT code,
502 * which used MAVROS for ASN.1 encoding. MAVROS had the interesting
503 * feature that it encoded data in the forward direction, which has
504 * it's problems, since you have no idea how long the data will be
505 * until after you're done. MAVROS solved this by reserving one byte
506 * for length, and later, if the actual length was longer, it reverted
507 * to indefinite, BER style, lengths. The version of MAVROS used by
508 * the DCE people could apparently generate correct X.509 DER encodings, and
509 * did this by making space for the length after encoding, but
510 * unfortunately this feature wasn't used with Kerberos.
514 _heim_fix_dce(size_t reallen, size_t *len)
516 if(reallen == ASN1_INDEFINITE)
525 der_get_bit_string (const unsigned char *p, size_t len,
526 heim_bit_string *data, size_t *size)
531 return ASN1_BAD_FORMAT;
532 if (len - 1 == 0 && p[0] != 0)
533 return ASN1_BAD_FORMAT;
534 /* check if any of the three upper bits are set
535 * any of them will cause a interger overrun */
536 if ((len - 1) >> (sizeof(len) * 8 - 3))
538 data->length = (len - 1) * 8;
539 data->data = malloc(len - 1);
540 if (data->data == NULL && (len - 1) != 0)
542 memcpy (data->data, p + 1, len - 1);
543 data->length -= p[0];
544 if(size) *size = len;