/* LibTomCrypt, modular cryptographic library -- Tom St Denis
*
* LibTomCrypt is a library that provides various cryptographic
* algorithms in a highly modular and flexible manner.
*
* The library is free for all purposes without any express
* guarantee it works.
*
* Tom St Denis, tomstdenis@gmail.com, http://libtomcrypt.com
*/
#include "tomcrypt.h"
/**
@file der_decode_choice.c
ASN.1 DER, decode a CHOICE, Tom St Denis
*/
#ifdef LTC_DER
/**
Decode a CHOICE
@param in The DER encoded input
@param inlen [in/out] The size of the input and resulting size of read type
@param list The list of items to decode
@param outlen The number of items in the list
@return CRYPT_OK on success
*/
int der_decode_choice(const unsigned char *in, unsigned long *inlen,
ltc_asn1_list *list, unsigned long outlen)
{
unsigned long size, x, z;
void *data;
LTC_ARGCHK(in != NULL);
LTC_ARGCHK(inlen != NULL);
LTC_ARGCHK(list != NULL);
/* get blk size */
if (*inlen < 2) {
return CRYPT_INVALID_PACKET;
}
/* set all of the "used" flags to zero */
for (x = 0; x < outlen; x++) {
list[x].used = 0;
}
/* now scan until we have a winner */
for (x = 0; x < outlen; x++) {
size = list[x].size;
data = list[x].data;
switch (list[x].type) {
case LTC_ASN1_INTEGER:
if (der_decode_integer(in, *inlen, data) == CRYPT_OK) {
if (der_length_integer(data, &z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_SHORT_INTEGER:
if (der_decode_short_integer(in, *inlen, data) == CRYPT_OK) {
if (der_length_short_integer(size, &z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_BIT_STRING:
if (der_decode_bit_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_bit_string(size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_OCTET_STRING:
if (der_decode_octet_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_octet_string(size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_NULL:
if (*inlen == 2 && in[x] == 0x05 && in[x+1] == 0x00) {
*inlen = 2;
list[x].used = 1;
return CRYPT_OK;
}
break;
case LTC_ASN1_OBJECT_IDENTIFIER:
if (der_decode_object_identifier(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_object_identifier(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_IA5_STRING:
if (der_decode_ia5_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_ia5_string(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_PRINTABLE_STRING:
if (der_decode_printable_string(in, *inlen, data, &size) == CRYPT_OK) {
if (der_length_printable_string(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
list[x].size = size;
*inlen = z;
return CRYPT_OK;
}
}
break;
case LTC_ASN1_UTCTIME:
z = *inlen;
if (der_decode_utctime(in, &z, data) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
break;
case LTC_ASN1_SET:
case LTC_ASN1_SETOF:
case LTC_ASN1_SEQUENCE:
if (der_decode_sequence(in, *inlen, data, size) == CRYPT_OK) {
if (der_length_sequence(data, size, &z) == CRYPT_OK) {
list[x].used = 1;
*inlen = z;
return CRYPT_OK;
}
}
break;
default:
return CRYPT_INVALID_ARG;
}
}
return CRYPT_INVALID_PACKET;
}
#endif
/* $Source: /cvs/libtom/libtomcrypt/src/pk/asn1/der/choice/der_decode_choice.c,v $ */
/* $Revision: 1.7 $ */
/* $Date: 2006/03/31 14:15:35 $ */
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