xref: /freebsd/crypto/heimdal/lib/asn1/der_length.c (revision daf1cffce2e07931f27c6c6998652e90df6ba87e)
1 /*
2  * Copyright (c) 1997, 1998, 1999 Kungliga Tekniska H�gskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
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.
16  *
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.
20  *
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
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "der_locl.h"
35 
36 RCSID("$Id: der_length.c,v 1.10 1999/12/02 17:05:01 joda Exp $");
37 
38 static size_t
39 length_unsigned (unsigned val)
40 {
41   size_t ret = 0;
42 
43   do {
44     ++ret;
45     val /= 256;
46   } while (val);
47   return ret;
48 }
49 
50 static size_t
51 length_int (int val)
52 {
53   size_t ret = 0;
54 
55   if (val == 0)
56     return 1;
57   while (val > 255 || val < -255) {
58     ++ret;
59     val /= 256;
60   }
61   if (val != 0) {
62     ++ret;
63     if ((signed char)val != val)
64       ++ret;
65     val /= 256;
66   }
67   return ret;
68 }
69 
70 size_t
71 length_len (size_t len)
72 {
73   if (len < 128)
74     return 1;
75   else
76     return length_unsigned (len) + 1;
77 }
78 
79 size_t
80 length_integer (const int *data)
81 {
82   size_t len = length_int (*data);
83 
84   return 1 + length_len(len) + len;
85 }
86 
87 size_t
88 length_general_string (const general_string *data)
89 {
90   char *str = *data;
91   size_t len = strlen(str);
92   return 1 + length_len(len) + len;
93 }
94 
95 size_t
96 length_octet_string (const octet_string *k)
97 {
98   return 1 + length_len(k->length) + k->length;
99 }
100 
101 size_t
102 length_generalized_time (const time_t *t)
103 {
104   octet_string k;
105   size_t ret;
106 
107   time2generalizedtime (*t, &k);
108   ret = 1 + length_len(k.length) + k.length;
109   free (k.data);
110   return ret;
111 }
112