Пример #1
0
int pkcs5_pbes2( asn1_buf *pbe_params, int mode,
                 const unsigned char *pwd,  size_t pwdlen,
                 const unsigned char *data, size_t datalen,
                 unsigned char *output )
{
    int ret, iterations = 0, keylen = 0;
    unsigned char *p, *end, *end2;
    asn1_buf kdf_alg_oid, enc_scheme_oid, salt;
    md_type_t md_type = POLARSSL_MD_SHA1;
    unsigned char key[32], iv[32];
    size_t len = 0, olen = 0;
    const md_info_t *md_info;
    const cipher_info_t *cipher_info;
    md_context_t md_ctx;
    cipher_context_t cipher_ctx;

    p = pbe_params->p;
    end = p + pbe_params->len;

    /*
     *  PBES2-params ::= SEQUENCE {
     *    keyDerivationFunc AlgorithmIdentifier {{PBES2-KDFs}},
     *    encryptionScheme AlgorithmIdentifier {{PBES2-Encs}}
     *  }
     */
    if( ( ret = asn1_get_tag( &p, end, &len,
            ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
    {
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT + ret );
    }

    if( ( ret = asn1_get_tag( &p, end, &len,
            ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
    {
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT + ret );
    }

    end2 = p + len;

    if( ( ret = asn1_get_tag( &p, end2, &kdf_alg_oid.len, ASN1_OID ) ) != 0 )
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT + ret );

    kdf_alg_oid.p = p;
    p += kdf_alg_oid.len;

    // Only PBKDF2 supported at the moment
    //
    if( !OID_CMP( OID_PKCS5_PBKDF2, &kdf_alg_oid ) )
        return( POLARSSL_ERR_PKCS5_FEATURE_UNAVAILABLE );

    if( ( ret = pkcs5_parse_pbkdf2_params( &p, end2,
                                           &salt, &iterations, &keylen,
                                           &md_type ) ) != 0 )
    {
        return( ret );
    }

    md_info = md_info_from_type( md_type );
    if( md_info == NULL )
        return( POLARSSL_ERR_PKCS5_FEATURE_UNAVAILABLE );

    if( ( ret = asn1_get_tag( &p, end, &len,
            ASN1_CONSTRUCTED | ASN1_SEQUENCE ) ) != 0 )
    {
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT + ret );
    }

    end2 = p + len;

    if( ( ret = asn1_get_tag( &p, end2, &enc_scheme_oid.len, ASN1_OID ) ) != 0 )
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT + ret );

    enc_scheme_oid.p = p;
    p += enc_scheme_oid.len;

#if defined(POLARSSL_DES_C)
    // Only DES-CBC and DES-EDE3-CBC supported at the moment
    //
    if( OID_CMP( OID_DES_EDE3_CBC, &enc_scheme_oid ) )
    {
        cipher_info = cipher_info_from_type( POLARSSL_CIPHER_DES_EDE3_CBC );
    }
    else if( OID_CMP( OID_DES_CBC, &enc_scheme_oid ) )
    {
        cipher_info = cipher_info_from_type( POLARSSL_CIPHER_DES_CBC );
    }
    else
#endif /* POLARSSL_DES_C */
        return( POLARSSL_ERR_PKCS5_FEATURE_UNAVAILABLE );

    if( cipher_info == NULL )
        return( POLARSSL_ERR_PKCS5_FEATURE_UNAVAILABLE );

    keylen = cipher_info->key_length / 8;

    if( ( ret = asn1_get_tag( &p, end2, &len, ASN1_OCTET_STRING ) ) != 0 )
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT + ret );

    if( len != cipher_info->iv_size )
        return( POLARSSL_ERR_PKCS5_INVALID_FORMAT );

    memcpy( iv, p, len );

    if( ( ret = md_init_ctx( &md_ctx, md_info ) ) != 0 )
        return( ret );

    if( ( ret = cipher_init_ctx( &cipher_ctx, cipher_info ) ) != 0 )
        return( ret );

    if ( ( ret = pkcs5_pbkdf2_hmac( &md_ctx, pwd, pwdlen, salt.p, salt.len,
                                    iterations, keylen, key ) ) != 0 )
    {
        return( ret );
    }

    if( ( ret = cipher_setkey( &cipher_ctx, key, keylen, mode ) ) != 0 )
        return( ret );

    if( ( ret = cipher_reset( &cipher_ctx, iv ) ) != 0 )
        return( ret );

    if( ( ret = cipher_update( &cipher_ctx, data, datalen,
                                output, &olen ) ) != 0 )
    {
        return( ret );
    }

    if( ( ret = cipher_finish( &cipher_ctx, output + olen, &olen ) ) != 0 )
        return( POLARSSL_ERR_PKCS5_PASSWORD_MISMATCH );

    return( 0 );
}
Пример #2
0
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 )
{
    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];
    size_t olen = 0;
    const mbedtls_md_info_t *md_info;
    const mbedtls_cipher_info_t *cipher_info;
    mbedtls_md_context_t md_ctx;
    mbedtls_cipher_type_t cipher_alg;
    mbedtls_cipher_context_t cipher_ctx;

    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_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_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 );
    }

    md_info = mbedtls_md_info_from_type( md_type );
    if( md_info == NULL )
        return( MBEDTLS_ERR_PKCS5_FEATURE_UNAVAILABLE );

    if( ( ret = mbedtls_asn1_get_alg( &p, end, &enc_scheme_oid,
                              &enc_scheme_params ) ) != 0 )
    {
        return( 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 = cipher_info->key_bitlen / 8;

    if( enc_scheme_params.tag != MBEDTLS_ASN1_OCTET_STRING ||
        enc_scheme_params.len != cipher_info->iv_size )
    {
        return( MBEDTLS_ERR_PKCS5_INVALID_FORMAT );
    }

    mbedtls_md_init( &md_ctx );
    mbedtls_cipher_init( &cipher_ctx );

    memcpy( iv, enc_scheme_params.p, enc_scheme_params.len );

    if( ( ret = mbedtls_md_setup( &md_ctx, md_info, 1 ) ) != 0 )
        goto exit;

    if( ( ret = mbedtls_pkcs5_pbkdf2_hmac( &md_ctx, 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( ( ret = mbedtls_cipher_crypt( &cipher_ctx, iv, enc_scheme_params.len,
                              data, datalen, output, &olen ) ) != 0 )
        ret = MBEDTLS_ERR_PKCS5_PASSWORD_MISMATCH;

exit:
    mbedtls_md_free( &md_ctx );
    mbedtls_cipher_free( &cipher_ctx );

    return( ret );
}