der_length_printable_string.c revision f7fc46c63fdc8f39234fea409b8dbe116d73ebf8 
1/* LibTomCrypt, modular cryptographic library -- Tom St Denis
2 *
3 * LibTomCrypt is a library that provides various cryptographic
4 * algorithms in a highly modular and flexible manner.
5 *
6 * The library is free for all purposes without any express
7 * guarantee it works.
8 *
9 * Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
10 */
11#include "tomcrypt.h"
12
13/**
14  @file der_length_printable_string.c
15  ASN.1 DER, get length of Printable STRING, Tom St Denis
16*/
17
18#ifdef LTC_DER
19
20static const struct {
21   int code, value;
22} printable_table[] = {
23{ ' ', 32 },
24{ '\'', 39 },
25{ '(', 40 },
26{ ')', 41 },
27{ '+', 43 },
28{ ',', 44 },
29{ '-', 45 },
30{ '.', 46 },
31{ '/', 47 },
32{ '0', 48 },
33{ '1', 49 },
34{ '2', 50 },
35{ '3', 51 },
36{ '4', 52 },
37{ '5', 53 },
38{ '6', 54 },
39{ '7', 55 },
40{ '8', 56 },
41{ '9', 57 },
42{ ':', 58 },
43{ '=', 61 },
44{ '?', 63 },
45{ 'A', 65 },
46{ 'B', 66 },
47{ 'C', 67 },
48{ 'D', 68 },
49{ 'E', 69 },
50{ 'F', 70 },
51{ 'G', 71 },
52{ 'H', 72 },
53{ 'I', 73 },
54{ 'J', 74 },
55{ 'K', 75 },
56{ 'L', 76 },
57{ 'M', 77 },
58{ 'N', 78 },
59{ 'O', 79 },
60{ 'P', 80 },
61{ 'Q', 81 },
62{ 'R', 82 },
63{ 'S', 83 },
64{ 'T', 84 },
65{ 'U', 85 },
66{ 'V', 86 },
67{ 'W', 87 },
68{ 'X', 88 },
69{ 'Y', 89 },
70{ 'Z', 90 },
71{ 'a', 97 },
72{ 'b', 98 },
73{ 'c', 99 },
74{ 'd', 100 },
75{ 'e', 101 },
76{ 'f', 102 },
77{ 'g', 103 },
78{ 'h', 104 },
79{ 'i', 105 },
80{ 'j', 106 },
81{ 'k', 107 },
82{ 'l', 108 },
83{ 'm', 109 },
84{ 'n', 110 },
85{ 'o', 111 },
86{ 'p', 112 },
87{ 'q', 113 },
88{ 'r', 114 },
89{ 's', 115 },
90{ 't', 116 },
91{ 'u', 117 },
92{ 'v', 118 },
93{ 'w', 119 },
94{ 'x', 120 },
95{ 'y', 121 },
96{ 'z', 122 },
97};
98
99int der_printable_char_encode(int c)
100{
101   int x;
102   for (x = 0; x < (int)(sizeof(printable_table)/sizeof(printable_table[0])); x++) {
103       if (printable_table[x].code == c) {
104          return printable_table[x].value;
105       }
106   }
107   return -1;
108}
109
110int der_printable_value_decode(int v)
111{
112   int x;
113   for (x = 0; x < (int)(sizeof(printable_table)/sizeof(printable_table[0])); x++) {
114       if (printable_table[x].value == v) {
115          return printable_table[x].code;
116       }
117   }
118   return -1;
119}
120
121/**
122  Gets length of DER encoding of Printable STRING
123  @param octets   The values you want to encode
124  @param noctets  The number of octets in the string to encode
125  @param outlen   [out] The length of the DER encoding for the given string
126  @return CRYPT_OK if successful
127*/
128int der_length_printable_string(const unsigned char *octets, unsigned long noctets, unsigned long *outlen)
129{
130   unsigned long x;
131
132   LTC_ARGCHK(outlen != NULL);
133   LTC_ARGCHK(octets != NULL);
134
135   /* scan string for validity */
136   for (x = 0; x < noctets; x++) {
137       if (der_printable_char_encode(octets[x]) == -1) {
138          return CRYPT_INVALID_ARG;
139       }
140   }
141
142   if (noctets < 128) {
143      /* 16 LL DD DD DD ... */
144      *outlen = 2 + noctets;
145   } else if (noctets < 256) {
146      /* 16 81 LL DD DD DD ... */
147      *outlen = 3 + noctets;
148   } else if (noctets < 65536UL) {
149      /* 16 82 LL LL DD DD DD ... */
150      *outlen = 4 + noctets;
151   } else if (noctets < 16777216UL) {
152      /* 16 83 LL LL LL DD DD DD ... */
153      *outlen = 5 + noctets;
154   } else {
155      return CRYPT_INVALID_ARG;
156   }
157
158   return CRYPT_OK;
159}
160
161#endif
162
163
164/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/printable_string/der_length_printable_string.c,v $ */
165/* $Revision: 1.2 $ */
166/* $Date: 2006/03/31 14:15:35 $ */
167