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/*
* Copyright (C) 2009 Martin Willi
* Hochschule fuer Technik Rapperswil
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*/
#include "pgp_encoder.h"
#include <debug.h>
/**
* Build a PGPv3 fingerprint
*/
static bool build_v3_fingerprint(chunk_t *encoding, va_list args)
{
hasher_t *hasher;
chunk_t n, e;
if (cred_encoding_args(args, CRED_PART_RSA_MODULUS, &n,
CRED_PART_RSA_PUB_EXP, &e, CRED_PART_END))
{
hasher = lib->crypto->create_hasher(lib->crypto, HASH_MD5);
if (!hasher)
{
DBG1(DBG_LIB, "MD5 hash algorithm not supported, PGP"
" fingerprinting failed");
return FALSE;
}
/* remove leading zero bytes before hashing modulus and exponent */
while (n.len > 0 && n.ptr[0] == 0x00)
{
n = chunk_skip(n, 1);
}
while (e.len > 0 && e.ptr[0] == 0x00)
{
e = chunk_skip(e, 1);
}
if (!hasher->allocate_hash(hasher, n, NULL) ||
!hasher->allocate_hash(hasher, e, encoding))
{
hasher->destroy(hasher);
return FALSE;
}
hasher->destroy(hasher);
return TRUE;
}
return FALSE;
}
/**
* See header.
*/
bool pgp_encoder_encode(cred_encoding_type_t type, chunk_t *encoding,
va_list args)
{
switch (type)
{
case KEYID_PGPV3:
return build_v3_fingerprint(encoding, args);
default:
return FALSE;
}
}
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