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|
/**
* \file pkcs5.c
*
* \brief PKCS#5 functions
*
* \author Mathias Olsson <mathias@kompetensum.com>
*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
/*
* PKCS#5 includes PBKDF2 and more
*
* http://tools.ietf.org/html/rfc2898 (Specification)
* http://tools.ietf.org/html/rfc6070 (Test vectors)
*/
#include "common.h"
#if defined(MBEDTLS_PKCS5_C)
#include "mbedtls/pkcs5.h"
#include "mbedtls/error.h"
#if defined(MBEDTLS_ASN1_PARSE_C)
#include "mbedtls/asn1.h"
#if defined(MBEDTLS_CIPHER_C)
#include "mbedtls/cipher.h"
#endif /* MBEDTLS_CIPHER_C */
#include "mbedtls/oid.h"
#endif /* MBEDTLS_ASN1_PARSE_C */
#include <string.h>
#include "mbedtls/platform.h"
#include "psa_util_internal.h"
#if defined(MBEDTLS_ASN1_PARSE_C) && defined(MBEDTLS_CIPHER_C)
static int pkcs5_parse_pbkdf2_params(const mbedtls_asn1_buf *params,
mbedtls_asn1_buf *salt, int *iterations,
int *keylen, mbedtls_md_type_t *md_type)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
mbedtls_asn1_buf prf_alg_oid;
unsigned char *p = params->p;
const unsigned char *end = params->p + params->len;
if (params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
}
/*
* PBKDF2-params ::= SEQUENCE {
* salt OCTET STRING,
* iterationCount INTEGER,
* keyLength INTEGER OPTIONAL
* prf AlgorithmIdentifier DEFAULT algid-hmacWithSHA1
* }
*
*/
if ((ret = mbedtls_asn1_get_tag(&p, end, &salt->len,
MBEDTLS_ASN1_OCTET_STRING)) != 0) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_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_PKCS5_INVALID_FORMAT, ret);
}
if (p == end) {
return 0;
}
if ((ret = mbedtls_asn1_get_int(&p, end, keylen)) != 0) {
if (ret != MBEDTLS_ERR_ASN1_UNEXPECTED_TAG) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
}
}
if (p == end) {
return 0;
}
if ((ret = mbedtls_asn1_get_alg_null(&p, end, &prf_alg_oid)) != 0) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
}
if (mbedtls_oid_get_md_hmac(&prf_alg_oid, md_type) != 0) {
return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
}
if (p != end) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
MBEDTLS_ERR_ASN1_LENGTH_MISMATCH);
}
return 0;
}
#if !defined(MBEDTLS_CIPHER_PADDING_PKCS7)
int mbedtls_pkcs5_pbes2_ext(const mbedtls_asn1_buf *pbe_params, int mode,
const unsigned char *pwd, size_t pwdlen,
const unsigned char *data, size_t datalen,
unsigned char *output, size_t output_size,
size_t *output_len);
#endif
#if !defined(MBEDTLS_DEPRECATED_REMOVED)
int mbedtls_pkcs5_pbes2(const mbedtls_asn1_buf *pbe_params, int mode,
const unsigned char *pwd, size_t pwdlen,
const unsigned char *data, size_t datalen,
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_pkcs5_pbes2_ext(pbe_params, mode, pwd, pwdlen, data,
datalen, output, SIZE_MAX, &output_len);
}
#endif
int mbedtls_pkcs5_pbes2_ext(const mbedtls_asn1_buf *pbe_params, int mode,
const unsigned char *pwd, size_t pwdlen,
const unsigned char *data, size_t datalen,
unsigned char *output, size_t output_size,
size_t *output_len)
{
int ret, iterations = 0, keylen = 0;
unsigned char *p, *end;
mbedtls_asn1_buf kdf_alg_oid, enc_scheme_oid, kdf_alg_params, enc_scheme_params;
mbedtls_asn1_buf salt;
mbedtls_md_type_t md_type = MBEDTLS_MD_SHA1;
unsigned char key[32], iv[32];
const mbedtls_cipher_info_t *cipher_info;
mbedtls_cipher_type_t cipher_alg;
mbedtls_cipher_context_t cipher_ctx;
unsigned int padlen = 0;
p = pbe_params->p;
end = p + pbe_params->len;
/*
* PBES2-params ::= SEQUENCE {
* keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
* encryptionScheme AlgorithmIdentifier {{PBES2-Encs}}
* }
*/
if (pbe_params->tag != (MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE)) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT,
MBEDTLS_ERR_ASN1_UNEXPECTED_TAG);
}
if ((ret = mbedtls_asn1_get_alg(&p, end, &kdf_alg_oid,
&kdf_alg_params)) != 0) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
}
// Only PBKDF2 supported at the moment
//
if (MBEDTLS_OID_CMP(MBEDTLS_OID_PKCS5_PBKDF2, &kdf_alg_oid) != 0) {
return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
}
if ((ret = pkcs5_parse_pbkdf2_params(&kdf_alg_params,
&salt, &iterations, &keylen,
&md_type)) != 0) {
return ret;
}
if ((ret = mbedtls_asn1_get_alg(&p, end, &enc_scheme_oid,
&enc_scheme_params)) != 0) {
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_PKCS5_INVALID_FORMAT, ret);
}
if (mbedtls_oid_get_cipher_alg(&enc_scheme_oid, &cipher_alg) != 0) {
return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
}
cipher_info = mbedtls_cipher_info_from_type(cipher_alg);
if (cipher_info == NULL) {
return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
}
/*
* The value of keylen from pkcs5_parse_pbkdf2_params() is ignored
* since it is optional and we don't know if it was set or not
*/
keylen = (int) mbedtls_cipher_info_get_key_bitlen(cipher_info) / 8;
if (enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING ||
enc_scheme_params.len != mbedtls_cipher_info_get_iv_size(cipher_info)) {
return MBEDTLS_ERR_PKCS5_INVALID_FORMAT;
}
if (mode == MBEDTLS_PKCS5_DECRYPT) {
if (output_size < datalen) {
return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
}
}
if (mode == MBEDTLS_PKCS5_ENCRYPT) {
padlen = cipher_info->block_size - (datalen % cipher_info->block_size);
if (output_size < (datalen + padlen)) {
return MBEDTLS_ERR_ASN1_BUF_TOO_SMALL;
}
}
mbedtls_cipher_init(&cipher_ctx);
memcpy(iv, enc_scheme_params.p, enc_scheme_params.len);
if ((ret = mbedtls_pkcs5_pbkdf2_hmac_ext(md_type, pwd, pwdlen, salt.p,
salt.len, iterations, keylen,
key)) != 0) {
goto exit;
}
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)
{
/* PKCS5 uses CBC with PKCS7 padding (which is the same as
* "PKCS5 padding" except that it's typically only called PKCS5
* with 64-bit-block ciphers).
*/
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_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 */
if ((ret = mbedtls_cipher_crypt(&cipher_ctx, iv, enc_scheme_params.len,
data, datalen, output, output_len)) != 0) {
ret = MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH;
}
exit:
mbedtls_cipher_free(&cipher_ctx);
return ret;
}
#endif /* MBEDTLS_ASN1_PARSE_C && MBEDTLS_CIPHER_C */
static int pkcs5_pbkdf2_hmac(mbedtls_md_context_t *ctx,
const unsigned char *password,
size_t plen, const unsigned char *salt, size_t slen,
unsigned int iteration_count,
uint32_t key_length, unsigned char *output)
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned int i;
unsigned char md1[MBEDTLS_MD_MAX_SIZE];
unsigned char work[MBEDTLS_MD_MAX_SIZE];
unsigned char md_size = mbedtls_md_get_size(ctx->md_info);
size_t use_len;
unsigned char *out_p = output;
unsigned char counter[4];
memset(counter, 0, 4);
counter[3] = 1;
#if UINT_MAX > 0xFFFFFFFF
if (iteration_count > 0xFFFFFFFF) {
return MBEDTLS_ERR_PKCS5_BAD_INPUT_DATA;
}
#endif
if ((ret = mbedtls_md_hmac_starts(ctx, password, plen)) != 0) {
return ret;
}
while (key_length) {
// U1 ends up in work
//
if ((ret = mbedtls_md_hmac_update(ctx, salt, slen)) != 0) {
goto cleanup;
}
if ((ret = mbedtls_md_hmac_update(ctx, counter, 4)) != 0) {
goto cleanup;
}
if ((ret = mbedtls_md_hmac_finish(ctx, work)) != 0) {
goto cleanup;
}
if ((ret = mbedtls_md_hmac_reset(ctx)) != 0) {
goto cleanup;
}
memcpy(md1, work, md_size);
for (i = 1; i < iteration_count; i++) {
// U2 ends up in md1
//
if ((ret = mbedtls_md_hmac_update(ctx, md1, md_size)) != 0) {
goto cleanup;
}
if ((ret = mbedtls_md_hmac_finish(ctx, md1)) != 0) {
goto cleanup;
}
if ((ret = mbedtls_md_hmac_reset(ctx)) != 0) {
goto cleanup;
}
// U1 xor U2
//
mbedtls_xor(work, work, md1, md_size);
}
use_len = (key_length < md_size) ? key_length : md_size;
memcpy(out_p, work, use_len);
key_length -= (uint32_t) use_len;
out_p += use_len;
for (i = 4; i > 0; i--) {
if (++counter[i - 1] != 0) {
break;
}
}
}
cleanup:
/* Zeroise buffers to clear sensitive data from memory. */
mbedtls_platform_zeroize(work, MBEDTLS_MD_MAX_SIZE);
mbedtls_platform_zeroize(md1, MBEDTLS_MD_MAX_SIZE);
return ret;
}
#if !defined(MBEDTLS_DEPRECATED_REMOVED)
int mbedtls_pkcs5_pbkdf2_hmac(mbedtls_md_context_t *ctx,
const unsigned char *password,
size_t plen, const unsigned char *salt, size_t slen,
unsigned int iteration_count,
uint32_t key_length, unsigned char *output)
{
return pkcs5_pbkdf2_hmac(ctx, password, plen, salt, slen, iteration_count,
key_length, output);
}
#endif
int mbedtls_pkcs5_pbkdf2_hmac_ext(mbedtls_md_type_t md_alg,
const unsigned char *password,
size_t plen, const unsigned char *salt, size_t slen,
unsigned int iteration_count,
uint32_t key_length, unsigned char *output)
{
mbedtls_md_context_t md_ctx;
const mbedtls_md_info_t *md_info = NULL;
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
md_info = mbedtls_md_info_from_type(md_alg);
if (md_info == NULL) {
return MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE;
}
mbedtls_md_init(&md_ctx);
if ((ret = mbedtls_md_setup(&md_ctx, md_info, 1)) != 0) {
goto exit;
}
ret = pkcs5_pbkdf2_hmac(&md_ctx, password, plen, salt, slen,
iteration_count, key_length, output);
exit:
mbedtls_md_free(&md_ctx);
return ret;
}
#if defined(MBEDTLS_SELF_TEST)
#if !defined(MBEDTLS_MD_CAN_SHA1)
int mbedtls_pkcs5_self_test(int verbose)
{
if (verbose != 0) {
mbedtls_printf(" PBKDF2 (SHA1): skipped\n\n");
}
return 0;
}
#else
#define MAX_TESTS 6
static const size_t plen_test_data[MAX_TESTS] =
{ 8, 8, 8, 24, 9 };
static const unsigned char password_test_data[MAX_TESTS][32] =
{
"password",
"password",
"password",
"passwordPASSWORDpassword",
"pass\0word",
};
static const size_t slen_test_data[MAX_TESTS] =
{ 4, 4, 4, 36, 5 };
static const unsigned char salt_test_data[MAX_TESTS][40] =
{
"salt",
"salt",
"salt",
"saltSALTsaltSALTsaltSALTsaltSALTsalt",
"sa\0lt",
};
static const uint32_t it_cnt_test_data[MAX_TESTS] =
{ 1, 2, 4096, 4096, 4096 };
static const uint32_t key_len_test_data[MAX_TESTS] =
{ 20, 20, 20, 25, 16 };
static const unsigned char result_key_test_data[MAX_TESTS][32] =
{
{ 0x0c, 0x60, 0xc8, 0x0f, 0x96, 0x1f, 0x0e, 0x71,
0xf3, 0xa9, 0xb5, 0x24, 0xaf, 0x60, 0x12, 0x06,
0x2f, 0xe0, 0x37, 0xa6 },
{ 0xea, 0x6c, 0x01, 0x4d, 0xc7, 0x2d, 0x6f, 0x8c,
0xcd, 0x1e, 0xd9, 0x2a, 0xce, 0x1d, 0x41, 0xf0,
0xd8, 0xde, 0x89, 0x57 },
{ 0x4b, 0x00, 0x79, 0x01, 0xb7, 0x65, 0x48, 0x9a,
0xbe, 0xad, 0x49, 0xd9, 0x26, 0xf7, 0x21, 0xd0,
0x65, 0xa4, 0x29, 0xc1 },
{ 0x3d, 0x2e, 0xec, 0x4f, 0xe4, 0x1c, 0x84, 0x9b,
0x80, 0xc8, 0xd8, 0x36, 0x62, 0xc0, 0xe4, 0x4a,
0x8b, 0x29, 0x1a, 0x96, 0x4c, 0xf2, 0xf0, 0x70,
0x38 },
{ 0x56, 0xfa, 0x6a, 0xa7, 0x55, 0x48, 0x09, 0x9d,
0xcc, 0x37, 0xd7, 0xf0, 0x34, 0x25, 0xe0, 0xc3 },
};
int mbedtls_pkcs5_self_test(int verbose)
{
int ret, i;
unsigned char key[64];
for (i = 0; i < MAX_TESTS; i++) {
if (verbose != 0) {
mbedtls_printf(" PBKDF2 (SHA1) #%d: ", i);
}
ret = mbedtls_pkcs5_pbkdf2_hmac_ext(MBEDTLS_MD_SHA1, password_test_data[i],
plen_test_data[i], salt_test_data[i],
slen_test_data[i], it_cnt_test_data[i],
key_len_test_data[i], key);
if (ret != 0 ||
memcmp(result_key_test_data[i], key, key_len_test_data[i]) != 0) {
if (verbose != 0) {
mbedtls_printf("failed\n");
}
ret = 1;
goto exit;
}
if (verbose != 0) {
mbedtls_printf("passed\n");
}
}
if (verbose != 0) {
mbedtls_printf("\n");
}
exit:
return ret;
}
#endif /* MBEDTLS_MD_CAN_SHA1 */
#endif /* MBEDTLS_SELF_TEST */
#endif /* MBEDTLS_PKCS5_C */
|