From 166310299a1e7824bbff17e1f016659d18b4a559 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Daniel=20P=2E=20Berrang=C3=A9?= Date: Tue, 20 Oct 2020 17:08:27 +0100 Subject: [PATCH] os: deprecate the -enable-fips option and QEMU's FIPS enforcement MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The -enable-fips option was added a long time ago to prevent the use of single DES when VNC when FIPS mode is enabled. It should never have been added, because apps are supposed to unconditionally honour FIPS mode based on the '/proc/sys/crypto/fips_enabled' file contents. In addition there is more to achieving FIPS compliance than merely blocking use of certain algorithms. Those algorithms which are used need to perform self-tests at runtime. QEMU's built-in cryptography provider has no support for self-tests, and neither does the nettle library. If QEMU is required to be used in a FIPS enabled host, then it must be built with the libgcrypt library enabled, which will unconditionally enforce FIPS compliance in any algorithm usage. Thus there is no need to keep either the -enable-fips option in QEMU, or QEMU's internal FIPS checking methods. Reviewed-by: John Snow Reviewed-by: Thomas Huth Signed-off-by: Daniel P. Berrangé --- docs/system/deprecated.rst | 12 ++++++++++++ os-posix.c | 3 +++ 2 files changed, 15 insertions(+) diff --git a/docs/system/deprecated.rst b/docs/system/deprecated.rst index 9de663526a..6ac757ed9f 100644 --- a/docs/system/deprecated.rst +++ b/docs/system/deprecated.rst @@ -134,6 +134,18 @@ Boolean options such as ``share=on``/``share=off`` could be written in short form as ``share`` and ``noshare``. This is now deprecated and will cause a warning. +``--enable-fips`` (since 6.0) +''''''''''''''''''''''''''''' + +This option restricts usage of certain cryptographic algorithms when +the host is operating in FIPS mode. + +If FIPS compliance is required, QEMU should be built with the ``libgcrypt`` +library enabled as a cryptography provider. + +Neither the ``nettle`` library, or the built-in cryptography provider are +supported on FIPS enabled hosts. + QEMU Machine Protocol (QMP) commands ------------------------------------ diff --git a/os-posix.c b/os-posix.c index 1de2839554..a6846f51c1 100644 --- a/os-posix.c +++ b/os-posix.c @@ -153,6 +153,9 @@ int os_parse_cmd_args(int index, const char *optarg) break; #if defined(CONFIG_LINUX) case QEMU_OPTION_enablefips: + warn_report("-enable-fips is deprecated, please build QEMU with " + "the `libgcrypt` library as the cryptography provider " + "to enable FIPS compliance"); fips_set_state(true); break; #endif