def ccm_decrypt_binary(encrypted_blob, hex_preexisting_128_bit_key, hex_preexisting_104_bit_iv, hex_preexisting_aad):
    """ Function to decrypt a CCM encrypted binary.
    input:
    encrypted_blob: Encrypted Binary blob to decrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key

    hex_preexisting_iv: hex representarion of image IV

    hex_preexisting_aad: hex representation of Additional Authentication data needed by the algorithm

    output:
    plaintext_binary: Decrypted plaintext binary
    """
    if hex_preexisting_aad == None:
        raise RuntimeError('AAD must be supplied')

    if hex_preexisting_128_bit_key==None:
        raise RuntimeError('Key must be supplied')
    else:
        encryption_key=hex_preexisting_128_bit_key

    if hex_preexisting_104_bit_iv == None:
        raise RuntimeError('IV must be supplied')
    else:
        image_iv=hex_preexisting_104_bit_iv

    encrypted_blob_file=utility_functions.store_data_to_temp_file(encrypted_blob)
    plaintext_binary_file_name=utility_functions.store_data_to_temp_file('')

    command_list=[ccm_crypto_path, "--input-file", encrypted_blob_file, '--key', encryption_key, '--iv', image_iv, '--output', plaintext_binary_file_name, '--operation=decrypt', '--aad', hex_preexisting_aad]
    utility_functions.system_command_logged(command_list)
    with open(plaintext_binary_file_name,'rb') as plaintext_output_file:
        plaintext_binary=plaintext_output_file.read()
    os.unlink(plaintext_binary_file_name)
    return plaintext_binary
def cbc_decrypt_binary(encrypted_blob, hex_preexisting_128_bit_key, hex_preexisting_iv):
    """ Function to decrypt a CBC encrypted binary.
    input:
    encrypted_blob: Encrypted Binary blob to decrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key

    hex_preexisting_iv: hex representarion of image IV

    output:
    plaintext_binary: Decrypted plaintext binary
    """

    if hex_preexisting_128_bit_key==None:
        raise RuntimeError('Key must be supplied')
    else:
        encryption_key=hex_preexisting_128_bit_key

    if hex_preexisting_iv == None:
        raise RuntimeError('IV must be supplied')
    else:
        image_iv=hex_preexisting_iv

    encrypted_blob_file=utility_functions.store_data_to_temp_file(encrypted_blob)
    plaintext_binary_file_name=utility_functions.store_data_to_temp_file('')

    command_list=[openssl_binary_path,"enc", "-aes-128-cbc", "-d", "-in", encrypted_blob_file, "-K", encryption_key, "-iv", image_iv, "-out", plaintext_binary_file_name, "-nopad"]
    utility_functions.system_command_logged(command_list)
    with open(plaintext_binary_file_name,'rb') as plaintext_output_file:
        plaintext_binary=plaintext_output_file.read()
    os.unlink(plaintext_binary_file_name)
    return plaintext_binary
def ccm_encrypt_binary(binary_blob, hex_preexisting_128_bit_key,
                       hex_preexisting_104_bit_iv, hex_preexisting_aad):
    """ Function to encrypt binary with a CCM 128 bit cipher.
    input:
    binary_blob: Binary blob to encrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key | None,
    if None, the key is generated

    hex_preexisting_iv: hex representarion of image IV | None,
    if None, the IV is generated

    hex_preexisting_aad: hex representation of Additional Authentication data needed by the algorithm

    output:
    (encrypted_binary, encryption_key, image_iv, hex_preexisting_aad): Tuple with the encrypted binary, the key, the IV, and the AAD
    """

    if hex_preexisting_aad == None:
        raise RuntimeError('AAD must be supplied')

    if hex_preexisting_128_bit_key == None:
        encryption_key = os.urandom(16)
        encryption_key = binascii.hexlify(encryption_key)

    else:
        encryption_key = hex_preexisting_128_bit_key

    if hex_preexisting_104_bit_iv == None:
        image_iv = os.urandom(13)
        image_iv = binascii.hexlify(image_iv)
    else:
        image_iv = hex_preexisting_104_bit_iv

    binary_blob_file = utility_functions.store_data_to_temp_file(binary_blob)
    encrypted_image_file_name = utility_functions.store_data_to_temp_file('')

    command_list = [
        ccm_crypto_path, "--input-file", binary_blob_file, '--key',
        encryption_key, '--iv', image_iv, '--output',
        encrypted_image_file_name, '--operation=encrypt', '--aad',
        hex_preexisting_aad
    ]
    utility_functions.system_command_logged(command_list)
    with open(encrypted_image_file_name, 'rb') as encrypted_output_file:
        encrypted_binary = encrypted_output_file.read()
    os.unlink(binary_blob_file)
    os.unlink(encrypted_image_file_name)
    return (encrypted_binary, encryption_key, image_iv, hex_preexisting_aad)
def _execute_openssl_certificate_command(command_list, key_pair, key_tempfile_name, shell=False):
    try:
        certificate_request = utility_functions.system_command_logged(command_list, stderr_to_temp=True, shell=shell)
    except subprocess.CalledProcessError, e:
        logger.critical("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) +
                                                                    " \nCommand = " + ' '.join(e.cmd))
def verify_certificate_chain(certificate_chain):
    """ Verify the certificate chain to be valid

    input:
    certificate_chain: [cert1,cert2,cert3]
    List of certificates (*in PEM FORMAT*) in the certificate chain. It assumes that the last certificate is the Root CA certificate.

    output:
    [True|False]
    Boolean value
    """
    CAfile_contents = _create_CAfile_contents_from_cert_chain(certificate_chain)

    CAfile_tempfile_name=utility_functions.store_data_to_temp_file(CAfile_contents)

    level1_cert_to_verify_contents = certificate_chain[0]

    level1_cert_to_verify_tempfile_name=utility_functions.store_data_to_temp_file(level1_cert_to_verify_contents)
    try:
        verify_level1_cert_command_out = utility_functions.system_command_logged([openssl_binary_path, 'verify', '-CAfile', CAfile_tempfile_name, level1_cert_to_verify_tempfile_name])
    except:
        logger.critical("verify_certificate_chain: OPENSSL could not verify cert chain")
    logger.debug("OpenSSL verify command output: " + verify_level1_cert_command_out)
    logger.debug("Deleting temporary files: " + CAfile_tempfile_name +", " + level1_cert_to_verify_tempfile_name)
    os.unlink(CAfile_tempfile_name)
    os.unlink(level1_cert_to_verify_tempfile_name)

    if verify_level1_cert_command_out.rstrip() == level1_cert_to_verify_tempfile_name + ": OK":
        logger.debug("The certificate chain is verified")
        return True
    else:
        logger.debug("The certificate chain is not verified")
        return False
def privkey_der_to_pem(der_privkey):
    """ Convert binary DER format PRIVATE key into base64 coded ASCII PEM format
    input:
    der_privkey: String containing binary PRIVATE KEY

    output
    pem_privkey: String containing base64 PEM PRIVATE KEY
    """
    pem_privkey = ''
    der_tempfile_name = utility_functions.store_data_to_temp_file(der_privkey)
    try:
        pem_privkey = utility_functions.system_command_logged(
            [
                openssl_binary_path, 'rsa', '-in', der_tempfile_name,
                '-inform', 'DER', '-outform', 'PEM'
            ],
            stderr_to_temp=True)
        logger.debug2("PEM Format Private Key: " + pem_privkey)
    except:
        logger.critical(
            "privkey_der_to_pem: OPENSSL Could not convert DER key to PEM")
    finally:
        os.unlink(der_tempfile_name)
        logger.debug("Deleting temporary file: " + der_tempfile_name)
    return pem_privkey
def privkey_pem_to_der(pem_privkey):
    """ Convert PEM format PRIVATE key into DER format
    input:
    pem_privkey: String containing base64 PEM Private key

    output
    der_privkey: String containing binary Private key
    """
    der_privkey = ''
    pem_tempfile_name = utility_functions.store_data_to_temp_file(pem_privkey)
    try:
        der_privkey = utility_functions.system_command_logged(
            [
                openssl_binary_path, 'rsa', '-in', pem_tempfile_name,
                '-inform', 'PEM', '-outform', 'DER'
            ],
            stderr_to_temp=True)
        logger.debug2("PEM Format private key: " + hexdump(der_privkey))
    except:
        logger.critical(
            "privkey_pem_to_der: OPENSSL Could not convert PEM key to DER key")
    finally:
        os.unlink(pem_tempfile_name)
        logger.debug("Deleting temporary file: " + pem_tempfile_name)
    return der_privkey
def cert_der_to_pem(der_certificate):
    """ Convert binary DER format certificate into base64 coded ASCII PEM format
    input:
    der_certificate: String containing binary certificate

    output
    pem_certificate: String containing base64 PEM certificate
    """

    der_tempfile_name = utility_functions.store_data_to_temp_file(
        der_certificate)
    try:
        pem_certificate = utility_functions.system_command_logged(
            [
                openssl_binary_path, 'x509', '-in', der_tempfile_name,
                '-inform', 'DER', '-outform', 'PEM'
            ],
            stderr_to_temp=True)
    except:
        logger.critical(
            "cert_der_to_pem: OPENSSL could not convert DER cert to PEM")
    logger.debug2("PEM Format certificate: " + pem_certificate)
    logger.debug("Deleting temporary file: " + der_tempfile_name)
    os.unlink(der_tempfile_name)
    return pem_certificate
def cert_pem_to_der(pem_certificate):
    """ Convert PEM format certificate into DER format
    input:
    pem_certificate: String containing base64 PEM certificate

    output
    der_certificate: String containing binary certificate
    """

    pem_tempfile_name = utility_functions.store_data_to_temp_file(
        pem_certificate)
    try:
        der_certificate = utility_functions.system_command_logged(
            [
                openssl_binary_path, 'x509', '-in', pem_tempfile_name,
                '-inform', 'PEM', '-outform', 'DER'
            ],
            stderr_to_temp=True)
    except:
        logger.critical(
            "cert_pem_to_der: OPENSSL could not convert PEM cert to DER")
    logger.debug2("PEM Format certificate: " + hexdump(der_certificate))
    logger.debug("Deleting temporary file: " + pem_tempfile_name)
    os.unlink(pem_tempfile_name)
    return der_certificate
def encrypt_with_private_key(message, private_key):
    """ Encrypt a message with a private key
    input:
        message: String representing message
        private_key: String representing the private key

    output:
        signature: String representing encrypted message
    """

    private_key_tempfile_name = utility_functions.store_data_to_temp_file(
        private_key)
    message_tempfile_name = utility_functions.store_data_to_temp_file(message)

    command_list = [
        openssl_binary_path, "rsautl", "-sign", "-pkcs", "-inkey",
        private_key_tempfile_name, '-in', message_tempfile_name
    ]
    try:
        encrypted_message = utility_functions.system_command_logged(
            command_list, stderr_to_temp=True)
    except:
        logger.critical(
            "encrypt_with_private_key: OPENSSL could not perform RSA sign operation"
        )

    return encrypted_message
def decrypt_with_public_key(encrypted_message, public_key):
    """ Decrypt an encrypted message with a public key
    input:
        encrypted_message = String representation of encrypted message
        public_key = String representation of public key

    output:
        message = String representing decrypted message
    """
    public_key_tempfile_name = utility_functions.store_data_to_temp_file(
        public_key)
    encrypted_message_tempfile_name = utility_functions.store_data_to_temp_file(
        encrypted_message)

    command_list = [
        openssl_binary_path, 'rsautl', '-inkey', public_key_tempfile_name,
        '-pubin', '-in', encrypted_message_tempfile_name
    ]
    try:
        message = utility_functions.system_command_logged(command_list,
                                                          stderr_to_temp=True)
    except:
        logger.critical(
            "decrypt_with_public_key: OPENSSL could not decrypt with public key"
        )
    return message
def decrypt_with_private_der_key(encrypted_message, private_key):
    """ Decrypt an encrypted message with a private key
    input:
        encrypted_message = String representation of encrypted message
        private_key = String representation of private key

    output:
        message = String representing decrypted message
    """
    private_key_tempfile_name = utility_functions.store_data_to_temp_file(
        private_key)
    encrypted_message_tempfile_name = utility_functions.store_data_to_temp_file(
        encrypted_message)
    pt_tempfile_name = utility_functions.store_data_to_temp_file('')
    command_list = [
        openssl_binary_path, 'rsautl', '-decrypt', '-inkey',
        private_key_tempfile_name, '-in', encrypted_message_tempfile_name,
        '-keyform', 'DER'
    ]
    try:
        message = utility_functions.system_command_logged(command_list,
                                                          stderr_to_temp=True)
        return message
    except:
        logger.debug2(
            "decrypt_with_private_der_key: OPENSSL could not decrypt with private key"
        )
def cbc_encrypt_binary(binary_blob, hex_preexisting_128_bit_key,
                       hex_preexisting_iv):
    """ Function to encrypt binary with a CBC 128 bit cipher.
    input:
    binary_blob: Binary blob to encrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key | None,
    if None, the key is generated

    hex_preexisting_iv: hex representarion of image IV | None,
    if None, the IV is generated

    output:
    (encrypted_binary, encryption_key, image_iv): Tuple with the encrypted binary, the key, and the IV
    """

    if hex_preexisting_128_bit_key == None:
        encryption_key = os.urandom(16)
        encryption_key = binascii.hexlify(encryption_key)

    else:
        encryption_key = hex_preexisting_128_bit_key

    if hex_preexisting_iv == None:
        image_iv = os.urandom(16)
        image_iv = binascii.hexlify(image_iv)
    else:
        image_iv = hex_preexisting_iv

    binary_blob_file = utility_functions.store_data_to_temp_file(binary_blob)
    encrypted_image_file_name = utility_functions.store_data_to_temp_file('')

    command_list = [
        openssl_binary_path, "enc", "-aes-128-cbc", "-in", binary_blob_file,
        "-K", encryption_key, "-iv", image_iv, "-out",
        encrypted_image_file_name, "-nopad"
    ]
    utility_functions.system_command_logged(command_list)
    with open(encrypted_image_file_name, 'rb') as encrypted_output_file:
        encrypted_binary = encrypted_output_file.read()
    os.unlink(binary_blob_file)
    os.unlink(encrypted_image_file_name)
    return (encrypted_binary, encryption_key, image_iv)
def ccm_encrypt_binary(binary_blob, hex_preexisting_128_bit_key, hex_preexisting_104_bit_iv, hex_preexisting_aad):
    """ Function to encrypt binary with a CCM 128 bit cipher.
    input:
    binary_blob: Binary blob to encrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key | None,
    if None, the key is generated

    hex_preexisting_iv: hex representarion of image IV | None,
    if None, the IV is generated

    hex_preexisting_aad: hex representation of Additional Authentication data needed by the algorithm

    output:
    (encrypted_binary, encryption_key, image_iv, hex_preexisting_aad): Tuple with the encrypted binary, the key, the IV, and the AAD
    """

    if hex_preexisting_aad == None:
        raise RuntimeError('AAD must be supplied')

    if hex_preexisting_128_bit_key==None:
        encryption_key = os.urandom(16)
        encryption_key = binascii.hexlify(encryption_key)

    else:
        encryption_key=hex_preexisting_128_bit_key

    if hex_preexisting_104_bit_iv == None:
        image_iv=os.urandom(13)
        image_iv=binascii.hexlify(image_iv)
    else:
        image_iv=hex_preexisting_104_bit_iv

    binary_blob_file=utility_functions.store_data_to_temp_file(binary_blob)
    encrypted_image_file_name=utility_functions.store_data_to_temp_file('')


    command_list=[ccm_crypto_path, "--input-file", binary_blob_file, '--key', encryption_key, '--iv', image_iv, '--output', encrypted_image_file_name, '--operation=encrypt', '--aad', hex_preexisting_aad]
    utility_functions.system_command_logged(command_list)
    with open(encrypted_image_file_name,'rb') as encrypted_output_file:
        encrypted_binary=encrypted_output_file.read()
    os.unlink(encrypted_image_file_name)
    return (encrypted_binary, encryption_key, image_iv, hex_preexisting_aad)
def gen_rsa_key_pair(key_size_in_bits, key_exponent, priv_key_output_file,
                     pub_key_output_file):
    """ Generate RSA Key pair

        input:

        key_size_in_bits: Size of the key in bits.
        key_exponent: [3, 65537]
                      Exponent used in key calculation.
        priv_key_output_file: File name for storing private key
        pub_key_output_file: File name for storing public key

        output:

        returned value: {"public_key": [Generated public key],
                         "private_key": [Generated private key] }
                         Dictionary holding the values of public and private keys
    """

    logger.debug("the openssl_binary is:{0}".format(openssl_binary_path))
    if key_exponent == 3:
        exponent_str = "-3"
    elif key_exponent == 65537:
        exponent_str = "-f4"
    else:
        logger.warning(
            "Exponent value supplied is INVALID! going with default exponent of 65537."
        )
        exponent_str = "-f4"

    key_size_str = str(key_size_in_bits)

    if priv_key_output_file is not None:
        pk_file = open(priv_key_output_file, "wb")
    else:
        pk_file = tempfile.NamedTemporaryFile(delete=False)
        logger.debug(
            "No output file specified for private key storage, so creating temp file: "
            + pk_file.name)

    try:
        private_key = utility_functions.system_command_logged(
            [openssl_binary_path, "genrsa", exponent_str, key_size_str],
            stderr_to_temp=True)
    except subprocess.CalledProcessError, e:
        os.unlink(pk_file.name)
        logger.critical(
            "gen_rsa_key_pair: OPENSSL Errored out on generation of RSA key.")
        logger.critical(
            "call to OpenSSL binary returned an error!: retval = " +
            str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError(
            "call to OpenSSL binary returned an error!: retval = " +
            str(e.returncode) + " Command = " + str(e.cmd))
def cbc_cts_encrypt_binary(binary_blob, hex_preexisting_128_bit_key, hex_preexisting_iv):
    """ Function to encrypt binary with a CBC 128 bit cipher.
    input:
    binary_blob: Binary blob to encrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key | None,
    if None, the key is generated

    hex_preexisting_iv: hex representarion of image IV | None,
    if None, the IV is generated

    output:
    (encrypted_binary, encryption_key, image_iv): Tuple with the encrypted binary, the key, and the IV
    """

    if hex_preexisting_128_bit_key==None:
        encryption_key = os.urandom(16)
        encryption_key = binascii.hexlify(encryption_key)

    else:
        encryption_key=hex_preexisting_128_bit_key

    if hex_preexisting_iv == None:
        image_iv=os.urandom(16)
        image_iv=binascii.hexlify(image_iv)
    else:
        image_iv=hex_preexisting_iv

    binary_blob_file=utility_functions.store_data_to_temp_file(binary_blob)
    encrypted_image_file_name=utility_functions.store_data_to_temp_file('')


    command_list=[cbc_crypto_path, "--input-file", binary_blob_file, '--key', encryption_key, '--iv', image_iv, '--output', encrypted_image_file_name, '--operation=encrypt']
    utility_functions.system_command_logged(command_list)
    with open(encrypted_image_file_name,'rb') as encrypted_output_file:
        encrypted_binary=encrypted_output_file.read()
    os.unlink(encrypted_image_file_name)
    return (encrypted_binary, encryption_key, image_iv)
Пример #17
0
def cbc_cts_decrypt_binary(encrypted_blob, hex_preexisting_128_bit_key,
                           hex_preexisting_iv):
    """ Function to decrypt a CBC encrypted binary.
    input:
    encrypted_blob: Encrypted Binary blob to decrypt
    hex_preexisting_128_bit_key: hex representarion of 128bit key

    hex_preexisting_iv: hex representarion of image IV

    output:
    plaintext_binary: Decrypted plaintext binary
    """

    if hex_preexisting_128_bit_key == None:
        raise RuntimeError('Key must be supplied')
    else:
        encryption_key = hex_preexisting_128_bit_key

    if hex_preexisting_iv == None:
        raise RuntimeError('IV must be supplied')
    else:
        image_iv = hex_preexisting_iv

    encrypted_blob_file = utility_functions.store_data_to_temp_file(
        encrypted_blob)
    plaintext_binary_file_name = "plaintext_binary.bin"

    command_list = [
        cbc_crypto_path, "--input-file", encrypted_blob_file, '--key',
        encryption_key, '--iv', image_iv, '--output',
        plaintext_binary_file_name, '--operation=decrypt'
    ]
    utility_functions.system_command_logged(command_list)
    with open(plaintext_binary_file_name, 'rb') as plaintext_output_file:
        plaintext_binary = plaintext_output_file.read()
    os.unlink(plaintext_binary_file_name)
    return plaintext_binary
def _sign_csr_with_CA_certificate(certificate_signing_request, CA_certificate,
                                  CA_key_pair, days, serial_num, extfile_name):
    """ Sign a Certificate signing request with a higher level CA certificate
    input:
    certificate_signing_request: String form of CSR
    CA_certificate: String representation of a higher level CA certificate

    CA_key_pair : {"public_key": [Generated public key],
                "private_key": [Generated private key] }
    The key pair of the CA_certificate

    days = validity period of certificate in days

    serial_num = Serial number of certificate

    extfile_name = Name of the extensions file to be used by openssl

    output:
    CA_signed_certificate: String representation of CA Signed certificate (PEM)
    CA_key_pair: {"public_key": CA public key,
                  "private_key": CA private key }
    """

    CA_certificate_tempfile_name = utility_functions.store_data_to_temp_file(
        CA_certificate)
    CA_privkey_tempfile_name = utility_functions.store_data_to_temp_file(
        CA_key_pair['private_key'])
    certificate_signing_request_tempfile_name = utility_functions.store_data_to_temp_file(
        certificate_signing_request)

    command_list = [
        openssl_binary_path, "x509", "-req", "-in",
        certificate_signing_request_tempfile_name, "-CAkey",
        CA_privkey_tempfile_name, "-CA", CA_certificate_tempfile_name, "-days",
        str(days), "-set_serial",
        str(serial_num), "-extfile", extfile_name, "-sha256"
    ]
    logger.debug("Command_list = " + repr(command_list))

    CA_signed_certificate = utility_functions.system_command_logged(
        command_list, stderr_to_temp=True)
    logger.debug("Generated Output of openssl certificate command: " +
                 CA_signed_certificate)

    os.unlink(CA_certificate_tempfile_name)
    os.unlink(CA_privkey_tempfile_name)
    os.unlink(certificate_signing_request_tempfile_name)

    return (CA_signed_certificate, CA_key_pair)
def get_public_key_from_private_key(private_key):
    """ Extracts public key from provided private key
    input:
    private_key: String representation of private key

    output:
    public key: String representation of public key
    """

    privkey_tempfile = utility_functions.store_data_to_temp_file(private_key)
    try:
        public_key = utility_functions.system_command_logged([openssl_binary_path, "rsa", "-in", privkey_tempfile, "-pubout"], stderr_to_temp=True)
    except subprocess.CalledProcessError, e:
        logger.critical("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
def get_public_key_from_certificate(certificate):
    if 'BEGIN CERTIFICATE' not in certificate:
        certificate = cert_der_to_pem(certificate)



    pubkey=_extract_public_key_from_certificate(certificate)
    pubkey_file_name=utility_functions.store_data_to_temp_file(pubkey)
    command_list=[openssl_binary_path,'rsa','-pubin','-inform','PEM','-text','-noout','<',pubkey_file_name]
    logger.debug("Command_list = " + repr(command_list))

    pubkey_text = utility_functions.system_command_logged(command_list, stderr_to_temp=True)
    logger.debug2("Pubkey text: " + pubkey_text)


    os.unlink(pubkey_file_name)
def privkey_der_to_pem(der_privkey):
    """ Convert binary DER format PRIVATE key into base64 coded ASCII PEM format
    input:
    der_privkey: String containing binary PRIVATE KEY

    output
    pem_privkey: String containing base64 PEM PRIVATE KEY
    """
    der_tempfile_name = utility_functions.store_data_to_temp_file(der_privkey)
    try:
        pem_privkey = utility_functions.system_command_logged([openssl_binary_path, 'rsa', '-in', der_tempfile_name, '-inform', 'DER', '-outform', 'PEM'], stderr_to_temp=True)
    except:
        logger.critical("privkey_der_to_pem: OPENSSL Could not convert DER key to PEM")
    logger.debug2("PEM Format Private Key: " + pem_privkey)
    logger.debug("Deleting temporary file: " + der_tempfile_name)
    os.unlink(der_tempfile_name)
    return pem_privkey
def privkey_pem_to_der(pem_privkey):
    """ Convert PEM format PRIVATE key into DER format
    input:
    pem_privkey: String containing base64 PEM Private key

    output
    der_privkey: String containing binary Private key
    """
    pem_tempfile_name = utility_functions.store_data_to_temp_file(pem_privkey)
    try:
        der_privkey = utility_functions.system_command_logged([openssl_binary_path, 'rsa', '-in', pem_tempfile_name, '-inform', 'PEM', '-outform', 'DER'], stderr_to_temp=True)
    except:
        logger.critical("privkey_pem_to_der: OPENSSL Could not convert PEM key to DER key")
    logger.debug2("PEM Format private key: " + hexdump(der_privkey))
    logger.debug("Deleting temporary file: " + pem_tempfile_name)
    os.unlink(pem_tempfile_name)
    return der_privkey
def _extract_public_key_from_certificate(certificate):
    """ Pulls out public key stored in certificate.
    input:
        certificate = String representation of PEM certificate

    output:
        public_key = String representation of public key in certificate
    """
    certificate_tempfile_name=utility_functions.store_data_to_temp_file(certificate)

    command_list = [openssl_binary_path, 'x509', '-in', certificate_tempfile_name, '-pubkey', '-noout', '-inform', 'PEM']
    try:
        public_key = utility_functions.system_command_logged(command_list)
    except:
        logger.critical("_extract_public_key_from_certificate: OPENSSL could not extract public key from cert")

    return public_key
def cert_der_to_pem(der_certificate):
    """ Convert binary DER format certificate into base64 coded ASCII PEM format
    input:
    der_certificate: String containing binary certificate

    output
    pem_certificate: String containing base64 PEM certificate
    """

    der_tempfile_name = utility_functions.store_data_to_temp_file(der_certificate)
    try:
        pem_certificate = utility_functions.system_command_logged([openssl_binary_path, 'x509', '-in', der_tempfile_name, '-inform', 'DER', '-outform', 'PEM'], stderr_to_temp=True)
    except:
        logger.critical("cert_der_to_pem: OPENSSL could not convert DER cert to PEM")
    logger.debug2("PEM Format certificate: " + pem_certificate)
    logger.debug("Deleting temporary file: " + der_tempfile_name)
    os.unlink(der_tempfile_name)
    return pem_certificate
def cert_pem_to_der(pem_certificate):
    """ Convert PEM format certificate into DER format
    input:
    pem_certificate: String containing base64 PEM certificate

    output
    der_certificate: String containing binary certificate
    """

    pem_tempfile_name = utility_functions.store_data_to_temp_file(pem_certificate)
    try:
        der_certificate = utility_functions.system_command_logged([openssl_binary_path, 'x509', '-in', pem_tempfile_name, '-inform', 'PEM', '-outform', 'DER'], stderr_to_temp=True)
    except:
        logger.critical("cert_pem_to_der: OPENSSL could not convert PEM cert to DER")
    logger.debug2("PEM Format certificate: " + hexdump(der_certificate))
    logger.debug("Deleting temporary file: " + pem_tempfile_name)
    os.unlink(pem_tempfile_name)
    return der_certificate
def decrypt_with_public_key(encrypted_message, public_key):
    """ Decrypt an encrypted message with a public key
    input:
        encrypted_message = String representation of encrypted message
        public_key = String representation of public key

    output:
        message = String representing decrypted message
    """
    public_key_tempfile_name =utility_functions.store_data_to_temp_file(public_key)
    encrypted_message_tempfile_name = utility_functions.store_data_to_temp_file(encrypted_message)

    command_list=[openssl_binary_path, 'rsautl', '-inkey', public_key_tempfile_name, '-pubin', '-in', encrypted_message_tempfile_name]
    try:
        message = utility_functions.system_command_logged(command_list, stderr_to_temp=True)
    except:
        logger.critical("decrypt_with_public_key: OPENSSL could not decrypt with public key")
    return message
def decrypt_with_private_der_key(encrypted_message, private_key):
    """ Decrypt an encrypted message with a private key
    input:
        encrypted_message = String representation of encrypted message
        private_key = String representation of private key

    output:
        message = String representing decrypted message
    """
    private_key_tempfile_name =utility_functions.store_data_to_temp_file(private_key)
    encrypted_message_tempfile_name = utility_functions.store_data_to_temp_file(encrypted_message)
    pt_tempfile_name=utility_functions.store_data_to_temp_file('')
    command_list=[openssl_binary_path, 'rsautl', '-decrypt', '-inkey', private_key_tempfile_name, '-in', encrypted_message_tempfile_name, '-keyform','DER']
    try:
        message = utility_functions.system_command_logged(command_list, stderr_to_temp=True)
        return message
    except:
        logger.debug2("decrypt_with_private_der_key: OPENSSL could not decrypt with private key")
def encrypt_with_private_key(message, private_key):
    """ Encrypt a message with a private key
    input:
        message: String representing message
        private_key: String representing the private key

    output:
        signature: String representing encrypted message
    """

    private_key_tempfile_name =utility_functions.store_data_to_temp_file(private_key)
    message_tempfile_name = utility_functions.store_data_to_temp_file(message)

    command_list = [openssl_binary_path, "rsautl", "-sign", "-pkcs", "-inkey", private_key_tempfile_name, '-in', message_tempfile_name]
    try:
        encrypted_message = utility_functions.system_command_logged(command_list, stderr_to_temp=True)
    except:
        logger.critical("encrypt_with_private_key: OPENSSL could not perform RSA sign operation")

    return encrypted_message
def generate_hash(hashing_algorithm, file_to_hash):
    """ Function to generate hashes of input file using the standard hashing algoritm specified

        input:  hashing_algorithm: ["SHA1"|"SHA256"]
                file_to_hash: The file to calculate the hash of.

        output: string representing hash of file_to_hash

    """
    if hashing_algorithm.lower() not in ["sha1", "sha256"]:
        logger.warning("The algorithm specified is invalid! Using SHA256 as default.")
        hashing_algorithm="-sha256"
    else:
        hashing_algorithm = "-" + hashing_algorithm

    try:
        generated_hash = utility_functions.system_command_logged([openssl_binary_path, "dgst", hashing_algorithm, file_to_hash]).rstrip().split("= ")[1]
    except:
        logger.critical("generate_hash: OPENSSL Hash generation failed")
    return generated_hash
def gen_rsa_key_pair(key_size_in_bits, key_exponent, priv_key_output_file, pub_key_output_file):
    """ Generate RSA Key pair

        input:

        key_size_in_bits: Size of the key in bits.
        key_exponent: [3, 65537]
                      Exponent used in key calculation.
        priv_key_output_file: File name for storing private key
        pub_key_output_file: File name for storing public key

        output:

        returned value: {"public_key": [Generated public key],
                         "private_key": [Generated private key] }
                         Dictionary holding the values of public and private keys
    """

    logger.debug("the openssl_binary is:{0}".format(openssl_binary_path))
    if key_exponent==3:
        exponent_str="-3"
    elif key_exponent == 65537:
        exponent_str="-f4"
    else:
        logger.warning("Exponent value supplied is INVALID! going with default exponent of 65537.")
        exponent_str="-f4"

    key_size_str=str(key_size_in_bits)

    if priv_key_output_file is not None:
        pk_file=open(priv_key_output_file,"wb")
    else:
        pk_file=tempfile.NamedTemporaryFile(delete=False)
        logger.debug("No output file specified for private key storage, so creating temp file: " + pk_file.name)

    try:
        private_key = utility_functions.system_command_logged([openssl_binary_path, "genrsa", exponent_str, key_size_str], stderr_to_temp=True)
    except subprocess.CalledProcessError, e:
        logger.critical("gen_rsa_key_pair: OPENSSL Errored out on generation of RSA key.")
        logger.critical("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
def _sign_csr_with_CA_certificate(certificate_signing_request, CA_certificate, CA_key_pair, days, serial_num, extfile_name):
    """ Sign a Certificate signing request with a higher level CA certificate
    input:
    certificate_signing_request: String form of CSR
    CA_certificate: String representation of a higher level CA certificate

    CA_key_pair : {"public_key": [Generated public key],
                "private_key": [Generated private key] }
    The key pair of the CA_certificate

    days = validity period of certificate in days

    serial_num = Serial number of certificate

    extfile_name = Name of the extensions file to be used by openssl

    output:
    CA_signed_certificate: String representation of CA Signed certificate (PEM)
    CA_key_pair: {"public_key": CA public key,
                  "private_key": CA private key }
    """

    CA_certificate_tempfile_name =utility_functions.store_data_to_temp_file(CA_certificate)
    CA_privkey_tempfile_name = utility_functions.store_data_to_temp_file(CA_key_pair['private_key'])
    certificate_signing_request_tempfile_name = utility_functions.store_data_to_temp_file(certificate_signing_request)

    command_list=[openssl_binary_path, "x509", "-req", "-in", certificate_signing_request_tempfile_name, "-CAkey",
                  CA_privkey_tempfile_name, "-CA", CA_certificate_tempfile_name, "-days", str(days),
                  "-set_serial", str(serial_num), "-extfile", extfile_name, "-sha256"]
    logger.debug("Command_list = " + repr(command_list))

    CA_signed_certificate = utility_functions.system_command_logged(command_list, stderr_to_temp=True)
    logger.debug("Generated Output of openssl certificate command: " + CA_signed_certificate)


    os.unlink(CA_certificate_tempfile_name)
    os.unlink(CA_privkey_tempfile_name)
    os.unlink(certificate_signing_request_tempfile_name)

    return (CA_signed_certificate, CA_key_pair)
        logger.critical(
            "gen_rsa_key_pair: OPENSSL Errored out on generation of RSA key.")
        logger.critical(
            "call to OpenSSL binary returned an error!: retval = " +
            str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError(
            "call to OpenSSL binary returned an error!: retval = " +
            str(e.returncode) + " Command = " + str(e.cmd))

    logger.debug("Writing generated private key to PEM file:" + pk_file.name)
    pk_file.write(private_key)
    pk_file.close()

    try:
        public_key = utility_functions.system_command_logged(
            [openssl_binary_path, "rsa", "-in", pk_file.name, "-pubout"],
            stderr_to_temp=True)
    except subprocess.CalledProcessError, e:
        logger.critical("gen_rsa_key_pair: OPENSSL could not get public key")
        logger.critical(
            "call to OpenSSL binary returned an error!: retval = " +
            str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError(
            "call to OpenSSL binary returned an error!: retval = " +
            str(e.returncode) + " Command = " + str(e.cmd))

    if pub_key_output_file is not None:
        logger.debug("Writing public key to file: " + pub_key_output_file)
        pubk_file = open(pub_key_output_file, "wb")
        pubk_file.write(public_key)
        pubk_file.close()
        pk_file=tempfile.NamedTemporaryFile(delete=False)
        logger.debug("No output file specified for private key storage, so creating temp file: " + pk_file.name)

    try:
        private_key = utility_functions.system_command_logged([openssl_binary_path, "genrsa", exponent_str, key_size_str], stderr_to_temp=True)
    except subprocess.CalledProcessError, e:
        logger.critical("gen_rsa_key_pair: OPENSSL Errored out on generation of RSA key.")
        logger.critical("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))

    logger.debug("Writing generated private key to PEM file:" + pk_file.name)
    pk_file.write(private_key)
    pk_file.close()

    try:
        public_key = utility_functions.system_command_logged([openssl_binary_path, "rsa", "-in", pk_file.name, "-pubout"], stderr_to_temp=True)
    except subprocess.CalledProcessError, e:
        logger.critical("gen_rsa_key_pair: OPENSSL could not get public key")
        logger.critical("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))
        raise RuntimeError("call to OpenSSL binary returned an error!: retval = " + str(e.returncode) + " Command = " + str(e.cmd))

    if pub_key_output_file is not None:
        logger.debug("Writing public key to file: " + pub_key_output_file)
        pubk_file=open(pub_key_output_file,"wb")
        pubk_file.write(public_key)
        pubk_file.close()

    if priv_key_output_file is None:
        logger.debug("Since private key file is temporary, deleting: " + pk_file.name)
        os.unlink(pk_file.name)