library/pkcs12.c - third_party/github/ARMmbed/mbedtls - Git at Google

 /*
  *  PKCS#12 Personal Information Exchange Syntax
  *
  *  Copyright The Mbed TLS Contributors
  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
  */
 /*
  *  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
  */

 #include "common.h"

 #if defined(MBEDTLS_PKCS12_C)

 #include "mbedtls/pkcs12.h"
 #include "mbedtls/asn1.h"
 #if defined(MBEDTLS_CIPHER_C)
 #include "mbedtls/cipher.h"
 #endif /* MBEDTLS_CIPHER_C */
 #include "mbedtls/platform_util.h"
 #include "mbedtls/error.h"

 #include <string.h>

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

 #include "psa_util_internal.h"

 #if defined(MBEDTLS_ASN1_PARSE_C) && defined(MBEDTLS_CIPHER_C)

 static int pkcs12_parse_pbe_params(mbedtls_asn1_buf *params,
                                    mbedtls_asn1_buf *salt, int *iterations)
 {
     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     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_ERROR_ADD(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_ERROR_ADD(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_ERROR_ADD(MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT, ret);
     }

     if (*p != end) {
         return MBEDTLS_ERROR_ADD(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

 #if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
 int mbedtls_pkcs12_pbe_ext(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, size_t output_size,
                            size_t *output_len);
 #endif

 #if !defined(MBEDTLS_DEPRECATED_REMOVED)
 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)
 {
     size_t output_len = 0;

     /* We assume caller of the function is providing a big enough output buffer
      * so we pass output_size as SIZE_MAX to pass checks, However, no guarantees
      * for the output size actually being correct.
      */
     return mbedtls_pkcs12_pbe_ext(pbe_params, mode, cipher_type, md_type,
                                   pwd, pwdlen, data, len, output, SIZE_MAX,
                                   &output_len);
 }
 #endif

 int mbedtls_pkcs12_pbe_ext(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, size_t output_size,
                            size_t *output_len)
 {
     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 iv_len = 0;
     size_t finish_olen = 0;
     unsigned int padlen = 0;

     if (pwd == NULL && pwdlen != 0) {
         return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
     }

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

     keylen = (int) mbedtls_cipher_info_get_key_bitlen(cipher_info) / 8;

     if (mode == MBEDTLS_PKCS12_PBE_DECRYPT) {
         if (output_size < len) {
             return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
         }
     }

     if (mode == MBEDTLS_PKCS12_PBE_ENCRYPT) {
         padlen = cipher_info->block_size - (len % cipher_info->block_size);
         if (output_size < (len + padlen)) {
             return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
         }
     }

     iv_len = mbedtls_cipher_info_get_iv_size(cipher_info);
     if ((ret = pkcs12_pbe_derive_key_iv(pbe_params, md_type, pwd, pwdlen,
                                         key, keylen,
                                         iv, iv_len)) != 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 defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
     {
         /* PKCS12 uses CBC with PKCS7 padding */
         mbedtls_cipher_padding_t padding = MBEDTLS_PADDING_PKCS7;
 #if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
         /* For historical reasons, when decrypting, this function works when
          * decrypting even when support for PKCS7 padding is disabled. In this
          * case, it ignores the padding, and so will never report a
          * password mismatch.
          */
         if (mode == MBEDTLS_PKCS12_PBE_DECRYPT) {
             padding = MBEDTLS_PADDING_NONE;
         }
 #endif
         if ((ret = mbedtls_cipher_set_padding_mode(&cipher_ctx, padding)) != 0) {
             goto exit;
         }
     }
 #endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */

     ret = mbedtls_cipher_crypt(&cipher_ctx, iv, iv_len, data, len, output, &finish_olen);
     if (ret == MBEDTLS_ERR_CIPHER_INVALID_PADDING) {
         ret = MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH;
     }

     *output_len += finish_olen;

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

     return ret;
 }

 #endif /* MBEDTLS_ASN1_PARSE_C && MBEDTLS_CIPHER_C */

 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;

     if (filler != NULL && fill_len != 0) {
         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;
         }
     } else {
         /* If either of the above are not true then clearly there is nothing
          * that this function can do. The function should *not* be called
          * under either of those circumstances, as you could end up with an
          * incorrect output but for safety's sake, leaving the check in as
          * otherwise we could end up with memory corruption.*/
     }
 }


 static int calculate_hashes(mbedtls_md_type_t md_type, int iterations,
                             unsigned char *diversifier, unsigned char *salt_block,
                             unsigned char *pwd_block, unsigned char *hash_output, int use_salt,
                             int use_password, size_t hlen, size_t v)
 {
     int ret = -1;
     size_t i;
     const mbedtls_md_info_t *md_info;
     mbedtls_md_context_t md_ctx;
     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;
     }
     // 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 (use_salt != 0) {
         if ((ret = mbedtls_md_update(&md_ctx, salt_block, v)) != 0) {
             goto exit;
         }
     }

     if (use_password != 0) {
         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;
         }
     }

 exit:
     mbedtls_md_free(&md_ctx);
     return ret;
 }


 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 = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
     unsigned int j;

     unsigned char diversifier[128];
     unsigned char salt_block[128], pwd_block[128], hash_block[128] = { 0 };
     unsigned char hash_output[MBEDTLS_MD_MAX_SIZE];
     unsigned char *p;
     unsigned char c;
     int           use_password = 0;
     int           use_salt = 0;

     size_t hlen, use_len, v, i;

     // 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;
     }

     if (pwd == NULL && pwdlen != 0) {
         return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
     }

     if (salt == NULL && saltlen != 0) {
         return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
     }

     use_password = (pwd && pwdlen != 0);
     use_salt = (salt && saltlen != 0);

     hlen = mbedtls_md_get_size_from_type(md_type);

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

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

     if (use_salt != 0) {
         pkcs12_fill_buffer(salt_block, v, salt, saltlen);
     }

     if (use_password != 0) {
         pkcs12_fill_buffer(pwd_block,  v, pwd,  pwdlen);
     }

     p = data;
     while (datalen > 0) {
         if (calculate_hashes(md_type, iterations, diversifier, salt_block,
                              pwd_block, hash_output, use_salt, use_password, hlen,
                              v) != 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;
             }
         }

         if (use_salt != 0) {
             // salt_block += B
             c = 0;
             for (i = v; i > 0; i--) {
                 j = salt_block[i - 1] + hash_block[i - 1] + c;
                 c = MBEDTLS_BYTE_1(j);
                 salt_block[i - 1] = MBEDTLS_BYTE_0(j);
             }
         }

         if (use_password != 0) {
             // pwd_block  += B
             c = 0;
             for (i = v; i > 0; i--) {
                 j = pwd_block[i - 1] + hash_block[i - 1] + c;
                 c = MBEDTLS_BYTE_1(j);
                 pwd_block[i - 1] = MBEDTLS_BYTE_0(j);
             }
         }
     }

     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));

     return ret;
 }

 #endif /* MBEDTLS_PKCS12_C */
	/*
	* PKCS#12 Personal Information Exchange Syntax
	*
	* Copyright The Mbed TLS Contributors
	* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
	*/
	/*
	* 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
	*/

	#include "common.h"

	#if defined(MBEDTLS_PKCS12_C)

	#include "mbedtls/pkcs12.h"
	#include "mbedtls/asn1.h"
	#if defined(MBEDTLS_CIPHER_C)
	#include "mbedtls/cipher.h"
	#endif /* MBEDTLS_CIPHER_C */
	#include "mbedtls/platform_util.h"
	#include "mbedtls/error.h"

	#include <string.h>

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

	#include "psa_util_internal.h"

	#if defined(MBEDTLS_ASN1_PARSE_C) && defined(MBEDTLS_CIPHER_C)

	static int pkcs12_parse_pbe_params(mbedtls_asn1_buf *params,
	mbedtls_asn1_buf salt, int iterations)
	{
	int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
	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_ERROR_ADD(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_ERROR_ADD(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_ERROR_ADD(MBEDTLS_ERR_PKCS12_PBE_INVALID_FORMAT, ret);
	}

	if (*p != end) {
	return MBEDTLS_ERROR_ADD(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

	#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
	int mbedtls_pkcs12_pbe_ext(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, size_t output_size,
	size_t *output_len);
	#endif

	#if !defined(MBEDTLS_DEPRECATED_REMOVED)
	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)
	{
	size_t output_len = 0;

	/* We assume caller of the function is providing a big enough output buffer
	* so we pass output_size as SIZE_MAX to pass checks, However, no guarantees
	* for the output size actually being correct.
	*/
	return mbedtls_pkcs12_pbe_ext(pbe_params, mode, cipher_type, md_type,
	pwd, pwdlen, data, len, output, SIZE_MAX,
	&output_len);
	}
	#endif

	int mbedtls_pkcs12_pbe_ext(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, size_t output_size,
	size_t *output_len)
	{
	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 iv_len = 0;
	size_t finish_olen = 0;
	unsigned int padlen = 0;

	if (pwd == NULL && pwdlen != 0) {
	return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
	}

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

	keylen = (int) mbedtls_cipher_info_get_key_bitlen(cipher_info) / 8;

	if (mode == MBEDTLS_PKCS12_PBE_DECRYPT) {
	if (output_size < len) {
	return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
	}
	}

	if (mode == MBEDTLS_PKCS12_PBE_ENCRYPT) {
	padlen = cipher_info->block_size - (len % cipher_info->block_size);
	if (output_size < (len + padlen)) {
	return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
	}
	}

	iv_len = mbedtls_cipher_info_get_iv_size(cipher_info);
	if ((ret = pkcs12_pbe_derive_key_iv(pbe_params, md_type, pwd, pwdlen,
	key, keylen,
	iv, iv_len)) != 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 defined(MBEDTLS_CIPHER_MODE_WITH_PADDING)
	{
	/* PKCS12 uses CBC with PKCS7 padding */
	mbedtls_cipher_padding_t padding = MBEDTLS_PADDING_PKCS7;
	#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
	/* For historical reasons, when decrypting, this function works when
	* decrypting even when support for PKCS7 padding is disabled. In this
	* case, it ignores the padding, and so will never report a
	* password mismatch.
	*/
	if (mode == MBEDTLS_PKCS12_PBE_DECRYPT) {
	padding = MBEDTLS_PADDING_NONE;
	}
	#endif
	if ((ret = mbedtls_cipher_set_padding_mode(&cipher_ctx, padding)) != 0) {
	goto exit;
	}
	}
	#endif /* MBEDTLS_CIPHER_MODE_WITH_PADDING */

	ret = mbedtls_cipher_crypt(&cipher_ctx, iv, iv_len, data, len, output, &finish_olen);
	if (ret == MBEDTLS_ERR_CIPHER_INVALID_PADDING) {
	ret = MBEDTLS_ERR_PKCS12_PASSWORD_MISMATCH;
	}

	*output_len += finish_olen;

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

	return ret;
	}

	#endif /* MBEDTLS_ASN1_PARSE_C && MBEDTLS_CIPHER_C */

	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;

	if (filler != NULL && fill_len != 0) {
	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;
	}
	} else {
	/* If either of the above are not true then clearly there is nothing
	* that this function can do. The function should not be called
	* under either of those circumstances, as you could end up with an
	* incorrect output but for safety's sake, leaving the check in as
	* otherwise we could end up with memory corruption.*/
	}
	}


	static int calculate_hashes(mbedtls_md_type_t md_type, int iterations,
	unsigned char diversifier, unsigned char salt_block,
	unsigned char pwd_block, unsigned char hash_output, int use_salt,
	int use_password, size_t hlen, size_t v)
	{
	int ret = -1;
	size_t i;
	const mbedtls_md_info_t *md_info;
	mbedtls_md_context_t md_ctx;
	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;
	}
	// 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 (use_salt != 0) {
	if ((ret = mbedtls_md_update(&md_ctx, salt_block, v)) != 0) {
	goto exit;
	}
	}

	if (use_password != 0) {
	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;
	}
	}

	exit:
	mbedtls_md_free(&md_ctx);
	return ret;
	}


	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 = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
	unsigned int j;

	unsigned char diversifier[128];
	unsigned char salt_block[128], pwd_block[128], hash_block[128] = { 0 };
	unsigned char hash_output[MBEDTLS_MD_MAX_SIZE];
	unsigned char *p;
	unsigned char c;
	int use_password = 0;
	int use_salt = 0;

	size_t hlen, use_len, v, i;

	// 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;
	}

	if (pwd == NULL && pwdlen != 0) {
	return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
	}

	if (salt == NULL && saltlen != 0) {
	return MBEDTLS_ERR_PKCS12_BAD_INPUT_DATA;
	}

	use_password = (pwd && pwdlen != 0);
	use_salt = (salt && saltlen != 0);

	hlen = mbedtls_md_get_size_from_type(md_type);

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

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

	if (use_salt != 0) {
	pkcs12_fill_buffer(salt_block, v, salt, saltlen);
	}

	if (use_password != 0) {
	pkcs12_fill_buffer(pwd_block, v, pwd, pwdlen);
	}

	p = data;
	while (datalen > 0) {
	if (calculate_hashes(md_type, iterations, diversifier, salt_block,
	pwd_block, hash_output, use_salt, use_password, hlen,
	v) != 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;
	}
	}

	if (use_salt != 0) {
	// salt_block += B
	c = 0;
	for (i = v; i > 0; i--) {
	j = salt_block[i - 1] + hash_block[i - 1] + c;
	c = MBEDTLS_BYTE_1(j);
	salt_block[i - 1] = MBEDTLS_BYTE_0(j);
	}
	}

	if (use_password != 0) {
	// pwd_block += B
	c = 0;
	for (i = v; i > 0; i--) {
	j = pwd_block[i - 1] + hash_block[i - 1] + c;
	c = MBEDTLS_BYTE_1(j);
	pwd_block[i - 1] = MBEDTLS_BYTE_0(j);
	}
	}
	}

	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));

	return ret;
	}

	#endif /* MBEDTLS_PKCS12_C */