[proxmark3-svn] / common / mbedtls / pkcs12.c

/*
 *  PKCS#12 Personal Information Exchange Syntax
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: GPL-2.0
 *
 *  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.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */
/*
 *  The PKCS #12 Personal Information Exchange Syntax Standard v1.1
 *
 *  http://www.rsa.com/rsalabs/pkcs/files/h11301-wp-pkcs-12v1-1-personal-information-exchange-syntax.pdf
 *  ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1-1.asn
 */

#if !defined(MBEDTLS_CONFIG_FILE)
#include "mbedtls/config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif

#if defined(MBEDTLS_PKCS12_C)

#include "mbedtls/pkcs12.h"
#include "mbedtls/asn1.h"
#include "mbedtls/cipher.h"
#include "mbedtls/platform_util.h"

#include <string.h>

#if defined(MBEDTLS_ARC4_C)
#include "mbedtls/arc4.h"
#endif

#if defined(MBEDTLS_DES_C)
#include "mbedtls/des.h"
#endif

static int pkcs12_parse_pbe_params( mbedtls_asn1_buf *params,
                                    mbedtls_asn1_buf *salt, int *iterations )
{
    int ret;
    unsigned char **p = &params->p;
    const unsigned char *end = params->p + params->len;

    /*
     *  pkcs-12PbeParams ::= SEQUENCE {
     *    salt          OCTET STRING,
     *    iterations    INTEGER
     *  }
     *
     */
    if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) )
        return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT +
                MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );

    if( ( ret = mbedtls_asn1_get_tag( p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
        return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT + ret );

    salt->p = *p;
    *p += salt->len;

    if( ( ret = mbedtls_asn1_get_int( p, end, iterations ) ) != 0 )
        return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT + ret );

    if( *p != end )
        return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT +
                MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );

    return( 0 );
}

#define PKCS12_MAX_PWDLEN 128

static int pkcs12_pbe_derive_key_iv( mbedtls_asn1_buf *pbe_params, mbedtls_md_type_t md_type,
                                     const unsigned char *pwd,  size_t pwdlen,
                                     unsigned char *key, size_t keylen,
                                     unsigned char *iv,  size_t ivlen )
{
    int ret, iterations = 0;
    mbedtls_asn1_buf salt;
    size_t i;
    unsigned char unipwd[PKCS12_MAX_PWDLEN * 2 + 2];

    if( pwdlen > PKCS12_MAX_PWDLEN )
        return( MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA );

    memset( &salt, 0, sizeof(mbedtls_asn1_buf) );
    memset( &unipwd, 0, sizeof(unipwd) );

    if( ( ret = pkcs12_parse_pbe_params( pbe_params, &salt,
                                         &iterations ) ) != 0 )
        return( ret );

    for( i = 0; i < pwdlen; i++ )
        unipwd[i * 2 + 1] = pwd[i];

    if( ( ret = mbedtls_pkcs12_derivation( key, keylen, unipwd, pwdlen * 2 + 2,
                                   salt.p, salt.len, md_type,
                                   MBEDTLS_PKCS12_DERIVE_KEY, iterations ) ) != 0 )
    {
        return( ret );
    }

    if( iv == NULL || ivlen == 0 )
        return( 0 );

    if( ( ret = mbedtls_pkcs12_derivation( iv, ivlen, unipwd, pwdlen * 2 + 2,
                                   salt.p, salt.len, md_type,
                                   MBEDTLS_PKCS12_DERIVE_IV, iterations ) ) != 0 )
    {
        return( ret );
    }
    return( 0 );
}

#undef PKCS12_MAX_PWDLEN

int mbedtls_pkcs12_pbe_sha1_rc4_128( mbedtls_asn1_buf *pbe_params, int mode,
                             const unsigned char *pwd,  size_t pwdlen,
                             const unsigned char *data, size_t len,
                             unsigned char *output )
{
#if !defined(MBEDTLS_ARC4_C)
    ((void) pbe_params);
    ((void) mode);
    ((void) pwd);
    ((void) pwdlen);
    ((void) data);
    ((void) len);
    ((void) output);
    return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );
#else
    int ret;
    unsigned char key[16];
    mbedtls_arc4_context ctx;
    ((void) mode);

    mbedtls_arc4_init( &ctx );

    if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, MBEDTLS_MD_SHA1,
                                          pwd, pwdlen,
                                          key, 16, NULL, 0 ) ) != 0 )
    {
        return( ret );
    }

    mbedtls_arc4_setup( &ctx, key, 16 );
    if( ( ret = mbedtls_arc4_crypt( &ctx, len, data, output ) ) != 0 )
        goto exit;

exit:
    mbedtls_platform_zeroize( key, sizeof( key ) );
    mbedtls_arc4_free( &ctx );

    return( ret );
#endif /* MBEDTLS_ARC4_C */
}

int mbedtls_pkcs12_pbe( mbedtls_asn1_buf *pbe_params, int mode,
                mbedtls_cipher_type_t cipher_type, mbedtls_md_type_t md_type,
                const unsigned char *pwd,  size_t pwdlen,
                const unsigned char *data, size_t len,
                unsigned char *output )
{
    int ret, keylen = 0;
    unsigned char key[32];
    unsigned char iv[16];
    const mbedtls_cipher_info_t *cipher_info;
    mbedtls_cipher_context_t cipher_ctx;
    size_t olen = 0;

    cipher_info = mbedtls_cipher_info_from_type( cipher_type );
    if( cipher_info == NULL )
        return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );

    keylen = cipher_info->key_bitlen / 8;

    if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, md_type, pwd, pwdlen,
                                          key, keylen,
                                          iv, cipher_info->iv_size ) ) != 0 )
    {
        return( ret );
    }

    mbedtls_cipher_init( &cipher_ctx );

    if( ( ret = mbedtls_cipher_setup( &cipher_ctx, cipher_info ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_cipher_setkey( &cipher_ctx, key, 8 * keylen, (mbedtls_operation_t) mode ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_cipher_set_iv( &cipher_ctx, iv, cipher_info->iv_size ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_cipher_reset( &cipher_ctx ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_cipher_update( &cipher_ctx, data, len,
                                output, &olen ) ) != 0 )
    {
        goto exit;
    }

    if( ( ret = mbedtls_cipher_finish( &cipher_ctx, output + olen, &olen ) ) != 0 )
        ret = MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH;

exit:
    mbedtls_platform_zeroize( key, sizeof( key ) );
    mbedtls_platform_zeroize( iv,  sizeof( iv  ) );
    mbedtls_cipher_free( &cipher_ctx );

    return( ret );
}

static void pkcs12_fill_buffer( unsigned char *data, size_t data_len,
                                const unsigned char *filler, size_t fill_len )
{
    unsigned char *p = data;
    size_t use_len;

    while( data_len > 0 )
    {
        use_len = ( data_len > fill_len ) ? fill_len : data_len;
        memcpy( p, filler, use_len );
        p += use_len;
        data_len -= use_len;
    }
}

int mbedtls_pkcs12_derivation( unsigned char *data, size_t datalen,
                       const unsigned char *pwd, size_t pwdlen,
                       const unsigned char *salt, size_t saltlen,
                       mbedtls_md_type_t md_type, int id, int iterations )
{
    int ret;
    unsigned int j;

    unsigned char diversifier[128];
    unsigned char salt_block[128], pwd_block[128], hash_block[128];
    unsigned char hash_output[MBEDTLS_MD_MAX_SIZE];
    unsigned char *p;
    unsigned char c;

    size_t hlen, use_len, v, i;

    const mbedtls_md_info_t *md_info;
    mbedtls_md_context_t md_ctx;

    // This version only allows max of 64 bytes of password or salt
    if( datalen > 128 || pwdlen > 64 || saltlen > 64 )
        return( MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA );

    md_info = mbedtls_md_info_from_type( md_type );
    if( md_info == NULL )
        return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );

    mbedtls_md_init( &md_ctx );

    if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
        return( ret );
    hlen = mbedtls_md_get_size( md_info );

    if( hlen <= 32 )
        v = 64;
    else
        v = 128;

    memset( diversifier, (unsigned char) id, v );

    pkcs12_fill_buffer( salt_block, v, salt, saltlen );
    pkcs12_fill_buffer( pwd_block,  v, pwd,  pwdlen  );

    p = data;
    while( datalen > 0 )
    {
        // Calculate hash( diversifier || salt_block || pwd_block )
        if( ( ret = mbedtls_md_starts( &md_ctx ) ) != 0 )
            goto exit;

        if( ( ret = mbedtls_md_update( &md_ctx, diversifier, v ) ) != 0 )
            goto exit;

        if( ( ret = mbedtls_md_update( &md_ctx, salt_block, v ) ) != 0 )
            goto exit;

        if( ( ret = mbedtls_md_update( &md_ctx, pwd_block, v ) ) != 0 )
            goto exit;

        if( ( ret = mbedtls_md_finish( &md_ctx, hash_output ) ) != 0 )
            goto exit;

        // Perform remaining ( iterations - 1 ) recursive hash calculations
        for( i = 1; i < (size_t) iterations; i++ )
        {
            if( ( ret = mbedtls_md( md_info, hash_output, hlen, hash_output ) ) != 0 )
                goto exit;
        }

        use_len = ( datalen > hlen ) ? hlen : datalen;
        memcpy( p, hash_output, use_len );
        datalen -= use_len;
        p += use_len;

        if( datalen == 0 )
            break;

        // Concatenating copies of hash_output into hash_block (B)
        pkcs12_fill_buffer( hash_block, v, hash_output, hlen );

        // B += 1
        for( i = v; i > 0; i-- )
            if( ++hash_block[i - 1] != 0 )
                break;

        // salt_block += B
        c = 0;
        for( i = v; i > 0; i-- )
        {
            j = salt_block[i - 1] + hash_block[i - 1] + c;
            c = (unsigned char) (j >> 8);
            salt_block[i - 1] = j & 0xFF;
        }

        // pwd_block  += B
        c = 0;
        for( i = v; i > 0; i-- )
        {
            j = pwd_block[i - 1] + hash_block[i - 1] + c;
            c = (unsigned char) (j >> 8);
            pwd_block[i - 1] = j & 0xFF;
        }
    }

    ret = 0;

exit:
    mbedtls_platform_zeroize( salt_block, sizeof( salt_block ) );
    mbedtls_platform_zeroize( pwd_block, sizeof( pwd_block ) );
    mbedtls_platform_zeroize( hash_block, sizeof( hash_block ) );
    mbedtls_platform_zeroize( hash_output, sizeof( hash_output ) );

    mbedtls_md_free( &md_ctx );

    return( ret );
}

#endif /* MBEDTLS_PKCS12_C */
Commit	Line	Data
700d8687 OM	1	/*
	2	* PKCS#12 Personal Information Exchange Syntax
	3	*
	4	* Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
	5	* SPDX-License-Identifier: GPL-2.0
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License along
	18	* with this program; if not, write to the Free Software Foundation, Inc.,
	19	* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
	20	*
	21	* This file is part of mbed TLS (https://tls.mbed.org)
	22	*/
	23	/*
	24	* The PKCS #12 Personal Information Exchange Syntax Standard v1.1
	25	*
	26	* http://www.rsa.com/rsalabs/pkcs/files/h11301-wp-pkcs-12v1-1-personal-information-exchange-syntax.pdf
	27	* ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1-1.asn
	28	*/
	29
	30	#if !defined(MBEDTLS_CONFIG_FILE)
	31	#include "mbedtls/config.h"
	32	#else
	33	#include MBEDTLS_CONFIG_FILE
	34	#endif
	35
	36	#if defined(MBEDTLS_PKCS12_C)
	37
	38	#include "mbedtls/pkcs12.h"
	39	#include "mbedtls/asn1.h"
	40	#include "mbedtls/cipher.h"
	41	#include "mbedtls/platform_util.h"
	42
	43	#include <string.h>
	44
	45	#if defined(MBEDTLS_ARC4_C)
	46	#include "mbedtls/arc4.h"
	47	#endif
	48
	49	#if defined(MBEDTLS_DES_C)
	50	#include "mbedtls/des.h"
	51	#endif
	52
	53	static int pkcs12_parse_pbe_params( mbedtls_asn1_buf *params,
	54	mbedtls_asn1_buf salt, int iterations )
	55	{
	56	int ret;
	57	unsigned char **p = &params->p;
	58	const unsigned char *end = params->p + params->len;
	59
	60	/*
	61	* pkcs-12PbeParams ::= SEQUENCE {
	62	* salt OCTET STRING,
	63	* iterations INTEGER
	64	* }
65	*
66	*/
67	if( params->tag != ( MBEDTLS_ASN1_CONSTRUCTED \| MBEDTLS_ASN1_SEQUENCE ) )
68	return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT +
69	MBEDTLS_ERR_ASN1_UNEXPECTED_TAG );
70
71	if( ( ret = mbedtls_asn1_get_tag( p, end, &salt->len, MBEDTLS_ASN1_OCTET_STRING ) ) != 0 )
72	return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT + ret );
73
74	salt->p = *p;
75	*p += salt->len;
76
77	if( ( ret = mbedtls_asn1_get_int( p, end, iterations ) ) != 0 )
78	return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT + ret );
79
80	if( *p != end )
81	return( MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT +
82	MBEDTLS_ERR_ASN1_LENGTH_MISMATCH );
83
84	return( 0 );
85	}
86
87	#define PKCS12_MAX_PWDLEN 128
88
89	static int pkcs12_pbe_derive_key_iv( mbedtls_asn1_buf *pbe_params, mbedtls_md_type_t md_type,
90	const unsigned char *pwd, size_t pwdlen,
91	unsigned char *key, size_t keylen,
92	unsigned char *iv, size_t ivlen )
93	{
94	int ret, iterations = 0;
95	mbedtls_asn1_buf salt;
96	size_t i;
97	unsigned char unipwd[PKCS12_MAX_PWDLEN * 2 + 2];
98
99	if( pwdlen > PKCS12_MAX_PWDLEN )
100	return( MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA );
101
102	memset( &salt, 0, sizeof(mbedtls_asn1_buf) );
103	memset( &unipwd, 0, sizeof(unipwd) );
104
105	if( ( ret = pkcs12_parse_pbe_params( pbe_params, &salt,
106	&iterations ) ) != 0 )
107	return( ret );
108
109	for( i = 0; i < pwdlen; i++ )
110	unipwd[i * 2 + 1] = pwd[i];
111
112	if( ( ret = mbedtls_pkcs12_derivation( key, keylen, unipwd, pwdlen * 2 + 2,
113	salt.p, salt.len, md_type,
114	MBEDTLS_PKCS12_DERIVE_KEY, iterations ) ) != 0 )
115	{
116	return( ret );
117	}
118
119	if( iv == NULL \|\| ivlen == 0 )
120	return( 0 );
121
122	if( ( ret = mbedtls_pkcs12_derivation( iv, ivlen, unipwd, pwdlen * 2 + 2,
123	salt.p, salt.len, md_type,
124	MBEDTLS_PKCS12_DERIVE_IV, iterations ) ) != 0 )
125	{
126	return( ret );
127	}
128	return( 0 );
129	}
130
131	#undef PKCS12_MAX_PWDLEN
132
133	int mbedtls_pkcs12_pbe_sha1_rc4_128( mbedtls_asn1_buf *pbe_params, int mode,
134	const unsigned char *pwd, size_t pwdlen,
135	const unsigned char *data, size_t len,
136	unsigned char *output )
137	{
138	#if !defined(MBEDTLS_ARC4_C)
139	((void) pbe_params);
140	((void) mode);
141	((void) pwd);
142	((void) pwdlen);
143	((void) data);
144	((void) len);
145	((void) output);
146	return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );
147	#else
148	int ret;
149	unsigned char key[16];
150	mbedtls_arc4_context ctx;
151	((void) mode);
152
153	mbedtls_arc4_init( &ctx );
154
155	if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, MBEDTLS_MD_SHA1,
156	pwd, pwdlen,
157	key, 16, NULL, 0 ) ) != 0 )
158	{
159	return( ret );
160	}
161
162	mbedtls_arc4_setup( &ctx, key, 16 );
163	if( ( ret = mbedtls_arc4_crypt( &ctx, len, data, output ) ) != 0 )
164	goto exit;
165
166	exit:
167	mbedtls_platform_zeroize( key, sizeof( key ) );
168	mbedtls_arc4_free( &ctx );
169
170	return( ret );
171	#endif /* MBEDTLS_ARC4_C */
172	}
173
174	int mbedtls_pkcs12_pbe( mbedtls_asn1_buf *pbe_params, int mode,
175	mbedtls_cipher_type_t cipher_type, mbedtls_md_type_t md_type,
176	const unsigned char *pwd, size_t pwdlen,
177	const unsigned char *data, size_t len,
178	unsigned char *output )
179	{
180	int ret, keylen = 0;
181	unsigned char key[32];
182	unsigned char iv[16];
183	const mbedtls_cipher_info_t *cipher_info;
184	mbedtls_cipher_context_t cipher_ctx;
185	size_t olen = 0;
186
187	cipher_info = mbedtls_cipher_info_from_type( cipher_type );
188	if( cipher_info == NULL )
189	return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );
190
191	keylen = cipher_info->key_bitlen / 8;
192
193	if( ( ret = pkcs12_pbe_derive_key_iv( pbe_params, md_type, pwd, pwdlen,
194	key, keylen,
195	iv, cipher_info->iv_size ) ) != 0 )
196	{
197	return( ret );
198	}
199
200	mbedtls_cipher_init( &cipher_ctx );
201
202	if( ( ret = mbedtls_cipher_setup( &cipher_ctx, cipher_info ) ) != 0 )
203	goto exit;
204
205	if( ( ret = mbedtls_cipher_setkey( &cipher_ctx, key, 8 * keylen, (mbedtls_operation_t) mode ) ) != 0 )
206	goto exit;
207
208	if( ( ret = mbedtls_cipher_set_iv( &cipher_ctx, iv, cipher_info->iv_size ) ) != 0 )
209	goto exit;
210
211	if( ( ret = mbedtls_cipher_reset( &cipher_ctx ) ) != 0 )
212	goto exit;
213
214	if( ( ret = mbedtls_cipher_update( &cipher_ctx, data, len,
215	output, &olen ) ) != 0 )
216	{
217	goto exit;
218	}
219
220	if( ( ret = mbedtls_cipher_finish( &cipher_ctx, output + olen, &olen ) ) != 0 )
221	ret = MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH;
222
223	exit:
224	mbedtls_platform_zeroize( key, sizeof( key ) );
225	mbedtls_platform_zeroize( iv, sizeof( iv ) );
226	mbedtls_cipher_free( &cipher_ctx );
227
228	return( ret );
229	}
230
231	static void pkcs12_fill_buffer( unsigned char *data, size_t data_len,
232	const unsigned char *filler, size_t fill_len )
233	{
234	unsigned char *p = data;
235	size_t use_len;
236
237	while( data_len > 0 )
238	{
239	use_len = ( data_len > fill_len ) ? fill_len : data_len;
240	memcpy( p, filler, use_len );
241	p += use_len;
242	data_len -= use_len;
243	}
244	}
245
246	int mbedtls_pkcs12_derivation( unsigned char *data, size_t datalen,
247	const unsigned char *pwd, size_t pwdlen,
248	const unsigned char *salt, size_t saltlen,
249	mbedtls_md_type_t md_type, int id, int iterations )
250	{
251	int ret;
252	unsigned int j;
253
254	unsigned char diversifier[128];
255	unsigned char salt_block[128], pwd_block[128], hash_block[128];
256	unsigned char hash_output[MBEDTLS_MD_MAX_SIZE];
257	unsigned char *p;
258	unsigned char c;
259
260	size_t hlen, use_len, v, i;
261
262	const mbedtls_md_info_t *md_info;
263	mbedtls_md_context_t md_ctx;
264
265	// This version only allows max of 64 bytes of password or salt
266	if( datalen > 128 \|\| pwdlen > 64 \|\| saltlen > 64 )
267	return( MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA );
268
269	md_info = mbedtls_md_info_from_type( md_type );
270	if( md_info == NULL )
271	return( MBEDTLS_ERR_PKCS12_FEATURE_UNAVAILABLE );
272
273	mbedtls_md_init( &md_ctx );
274
275	if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 0 ) ) != 0 )
276	return( ret );
277	hlen = mbedtls_md_get_size( md_info );
278
279	if( hlen <= 32 )
280	v = 64;
281	else
282	v = 128;
283
284	memset( diversifier, (unsigned char) id, v );
285
286	pkcs12_fill_buffer( salt_block, v, salt, saltlen );
287	pkcs12_fill_buffer( pwd_block, v, pwd, pwdlen );
288
289	p = data;
290	while( datalen > 0 )
291	{
292	// Calculate hash( diversifier \|\| salt_block \|\| pwd_block )
293	if( ( ret = mbedtls_md_starts( &md_ctx ) ) != 0 )
294	goto exit;
295
296	if( ( ret = mbedtls_md_update( &md_ctx, diversifier, v ) ) != 0 )
297	goto exit;
298
299	if( ( ret = mbedtls_md_update( &md_ctx, salt_block, v ) ) != 0 )
300	goto exit;
301
302	if( ( ret = mbedtls_md_update( &md_ctx, pwd_block, v ) ) != 0 )
303	goto exit;
304
305	if( ( ret = mbedtls_md_finish( &md_ctx, hash_output ) ) != 0 )
306	goto exit;
307
308	// Perform remaining ( iterations - 1 ) recursive hash calculations
309	for( i = 1; i < (size_t) iterations; i++ )
310	{
311	if( ( ret = mbedtls_md( md_info, hash_output, hlen, hash_output ) ) != 0 )
312	goto exit;
313	}
314
315	use_len = ( datalen > hlen ) ? hlen : datalen;
316	memcpy( p, hash_output, use_len );
317	datalen -= use_len;
318	p += use_len;
319
320	if( datalen == 0 )
321	break;
322
323	// Concatenating copies of hash_output into hash_block (B)
324	pkcs12_fill_buffer( hash_block, v, hash_output, hlen );
325
326	// B += 1
327	for( i = v; i > 0; i-- )
328	if( ++hash_block[i - 1] != 0 )
329	break;
330
331	// salt_block += B
332	c = 0;
333	for( i = v; i > 0; i-- )
334	{
335	j = salt_block[i - 1] + hash_block[i - 1] + c;
336	c = (unsigned char) (j >> 8);
337	salt_block[i - 1] = j & 0xFF;
338	}
339
340	// pwd_block += B
341	c = 0;
342	for( i = v; i > 0; i-- )
343	{
344	j = pwd_block[i - 1] + hash_block[i - 1] + c;
345	c = (unsigned char) (j >> 8);
346	pwd_block[i - 1] = j & 0xFF;
347	}
348	}
349
350	ret = 0;
351
352	exit:
353	mbedtls_platform_zeroize( salt_block, sizeof( salt_block ) );
354	mbedtls_platform_zeroize( pwd_block, sizeof( pwd_block ) );
355	mbedtls_platform_zeroize( hash_block, sizeof( hash_block ) );
356	mbedtls_platform_zeroize( hash_output, sizeof( hash_output ) );
357
358	mbedtls_md_free( &md_ctx );
359
360	return( ret );
361	}
362
363	#endif /* MBEDTLS_PKCS12_C */