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_decode_choice.c
15 ASN.1 DER, decode a CHOICE, Tom St Denis
16 */
17
18 #ifdef LTC_DER
19
20 /**
21 Decode a CHOICE
22 @param in The DER encoded input
23 @param inlen [in/out] The size of the input and resulting size of read type
24 @param list The list of items to decode
25 @param outlen The number of items in the list
26 @return CRYPT_OK on success
27 */
der_decode_choice(const unsigned char * in,unsigned long * inlen,ltc_asn1_list * list,unsigned long outlen)28 int der_decode_choice(const unsigned char *in, unsigned long *inlen,
29 ltc_asn1_list *list, unsigned long outlen)
30 {
31 unsigned long size, x, z;
32 void *data;
33
34 LTC_ARGCHK(in != NULL);
35 LTC_ARGCHK(inlen != NULL);
36 LTC_ARGCHK(list != NULL);
37
38 /* get blk size */
39 if (*inlen < 2) {
40 return CRYPT_INVALID_PACKET;
41 }
42
43 /* set all of the "used" flags to zero */
44 for (x = 0; x < outlen; x++) {
45 list[x].used = 0;
46 }
47
48 /* now scan until we have a winner */
49 for (x = 0; x < outlen; x++) {
50 size = list[x].size;
51 data = list[x].data;
52
53 switch (list[x].type) {
54 case LTC_ASN1_INTEGER:
55 if (der_decode_integer(in, *inlen, data) == CRYPT_OK) {
56 if (der_length_integer(data, &z) == CRYPT_OK) {
57 list[x].used = 1;
58 *inlen = z;
59 return CRYPT_OK;
60 }
61 }
62 break;
63
64 case LTC_ASN1_SHORT_INTEGER:
65 if (der_decode_short_integer(in, *inlen, data) == CRYPT_OK) {
66 if (der_length_short_integer(size, &z) == CRYPT_OK) {
67 list[x].used = 1;
68 *inlen = z;
69 return CRYPT_OK;
70 }
71 }
72 break;
73
74 case LTC_ASN1_BIT_STRING:
75 if (der_decode_bit_string(in, *inlen, data, &size) == CRYPT_OK) {
76 if (der_length_bit_string(size, &z) == CRYPT_OK) {
77 list[x].used = 1;
78 list[x].size = size;
79 *inlen = z;
80 return CRYPT_OK;
81 }
82 }
83 break;
84
85 case LTC_ASN1_OCTET_STRING:
86 if (der_decode_octet_string(in, *inlen, data, &size) == CRYPT_OK) {
87 if (der_length_octet_string(size, &z) == CRYPT_OK) {
88 list[x].used = 1;
89 list[x].size = size;
90 *inlen = z;
91 return CRYPT_OK;
92 }
93 }
94 break;
95
96 case LTC_ASN1_NULL:
97 if (*inlen == 2 && in[x] == 0x05 && in[x+1] == 0x00) {
98 *inlen = 2;
99 list[x].used = 1;
100 return CRYPT_OK;
101 }
102 break;
103
104 case LTC_ASN1_OBJECT_IDENTIFIER:
105 if (der_decode_object_identifier(in, *inlen, data, &size) == CRYPT_OK) {
106 if (der_length_object_identifier(data, size, &z) == CRYPT_OK) {
107 list[x].used = 1;
108 list[x].size = size;
109 *inlen = z;
110 return CRYPT_OK;
111 }
112 }
113 break;
114
115 case LTC_ASN1_IA5_STRING:
116 if (der_decode_ia5_string(in, *inlen, data, &size) == CRYPT_OK) {
117 if (der_length_ia5_string(data, size, &z) == CRYPT_OK) {
118 list[x].used = 1;
119 list[x].size = size;
120 *inlen = z;
121 return CRYPT_OK;
122 }
123 }
124 break;
125
126
127 case LTC_ASN1_PRINTABLE_STRING:
128 if (der_decode_printable_string(in, *inlen, data, &size) == CRYPT_OK) {
129 if (der_length_printable_string(data, size, &z) == CRYPT_OK) {
130 list[x].used = 1;
131 list[x].size = size;
132 *inlen = z;
133 return CRYPT_OK;
134 }
135 }
136 break;
137
138 case LTC_ASN1_UTF8_STRING:
139 if (der_decode_utf8_string(in, *inlen, data, &size) == CRYPT_OK) {
140 if (der_length_utf8_string(data, size, &z) == CRYPT_OK) {
141 list[x].used = 1;
142 list[x].size = size;
143 *inlen = z;
144 return CRYPT_OK;
145 }
146 }
147 break;
148
149 case LTC_ASN1_UTCTIME:
150 z = *inlen;
151 if (der_decode_utctime(in, &z, data) == CRYPT_OK) {
152 list[x].used = 1;
153 *inlen = z;
154 return CRYPT_OK;
155 }
156 break;
157
158 case LTC_ASN1_SET:
159 case LTC_ASN1_SETOF:
160 case LTC_ASN1_SEQUENCE:
161 if (der_decode_sequence(in, *inlen, data, size) == CRYPT_OK) {
162 if (der_length_sequence(data, size, &z) == CRYPT_OK) {
163 list[x].used = 1;
164 *inlen = z;
165 return CRYPT_OK;
166 }
167 }
168 break;
169
170 default:
171 return CRYPT_INVALID_ARG;
172 }
173 }
174
175 return CRYPT_INVALID_PACKET;
176 }
177
178 #endif
179
180 /* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/choice/der_decode_choice.c,v $ */
181 /* $Revision: 1.8 $ */
182 /* $Date: 2006/12/06 02:23:49 $ */
183