Am Donnerstag, 16. Januar 2020, 01:14:35 CET schrieb Randy Dunlap: Hi Randy, > On 1/15/20 2:33 AM, Stephan Müller wrote: > > CC: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> > > CC: "Alexander E. Patrakov" <patrakov@xxxxxxxxx> > > CC: "Ahmed S. Darwish" <darwish.07@xxxxxxxxx> > > CC: "Theodore Y. Ts'o" <tytso@xxxxxxx> > > CC: Willy Tarreau <w@xxxxxx> > > CC: Matthew Garrett <mjg59@xxxxxxxxxxxxx> > > CC: Vito Caputo <vcaputo@xxxxxxxxxxx> > > CC: Andreas Dilger <adilger.kernel@xxxxxxxxx> > > CC: Jan Kara <jack@xxxxxxx> > > CC: Ray Strode <rstrode@xxxxxxxxxx> > > CC: William Jon McCann <mccann@xxxxxxx> > > CC: zhangjs <zachary@xxxxxxxxxxxxxxxx> > > CC: Andy Lutomirski <luto@xxxxxxxxxx> > > CC: Florian Weimer <fweimer@xxxxxxxxxx> > > CC: Lennart Poettering <mzxreary@xxxxxxxxxxx> > > CC: Nicolai Stange <nstange@xxxxxxx> > > Reviewed-by: Roman Drahtmueller <draht@xxxxxxxxxxxxxx> > > Tested-by: Roman Drahtmüller <draht@xxxxxxxxxxxxxx> > > Tested-by: Marcelo Henrique Cerri <marcelo.cerri@xxxxxxxxxxxxx> > > Tested-by: Neil Horman <nhorman@xxxxxxxxxx> > > Signed-off-by: Stephan Mueller <smueller@xxxxxxxxxx> > > --- > > > > drivers/char/lrng/Kconfig | 11 ++ > > drivers/char/lrng/Makefile | 1 + > > drivers/char/lrng/lrng_drbg.c | 260 ++++++++++++++++++++++++++++++++++ > > 3 files changed, 272 insertions(+) > > create mode 100644 drivers/char/lrng/lrng_drbg.c > > > > diff --git a/drivers/char/lrng/Kconfig b/drivers/char/lrng/Kconfig > > index cb701bb0b8b6..15fb623d9d1f 100644 > > --- a/drivers/char/lrng/Kconfig > > +++ b/drivers/char/lrng/Kconfig > > @@ -71,4 +71,15 @@ menuconfig LRNG_DRNG_SWITCH > > > > accessible via the external interfaces. With this configuration > > option other DRNGs can be selected and loaded at runtime. > > > > +if LRNG_DRNG_SWITCH > > +config LRNG_DRBG > > + tristate "SP800-90A support for the LRNG" > > + select CRYPTO_DRBG_MENU > > + select CRYPTO_CMAC if CRYPTO_DRBG_CTR > > Don't select these if CRYPTO is not already set/enabled. > It causes Kconfig warnings and possible build errors. I added "depends on CRYPTO" > > > + help > > + Enable the SP800-90A DRBG support for the LRNG. Once the > > + module is loaded, output from /dev/random, /dev/urandom, > > + getrandom(2), or get_random_bytes is provided by a DRBG. > > +endif # LRNG_DRNG_SWITCH > > + > > > > endif # LRNG > > > > diff --git a/drivers/char/lrng/lrng_drbg.c b/drivers/char/lrng/lrng_drbg.c > > new file mode 100644 > > index 000000000000..8bf2badb1fe0 > > --- /dev/null > > +++ b/drivers/char/lrng/lrng_drbg.c > > @@ -0,0 +1,260 @@ > > +// SPDX-License-Identifier: GPL-2.0 OR BSD-2-Clause > > +/* > > + * Backend for the LRNG providing the cryptographic primitives using the > > + * kernel crypto API and its DRBG. > > + * > > + * Copyright (C) 2016 - 2020, Stephan Mueller <smueller@xxxxxxxxxx> > > + */ > > + > > +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt > > + > > +#include <crypto/drbg.h> > > +#include <linux/init.h> > > +#include <linux/module.h> > > +#include <linux/lrng.h> > > + > > +/* > > + * Define a DRBG plus a hash / MAC used to extract data from the entropy > > pool. + * For LRNG_HASH_NAME you can use a hash or a MAC (HMAC or CMAC) > > of your choice + * (Note, you should use the suggested selections below > > -- using SHA-1 or MD5 + * is not wise). The idea is that the used cipher > > primitive can be selected to + * be the same as used for the DRBG. I.e. > > the LRNG only uses one cipher + * primitive using the same cipher > > implementation with the options offered in + * the following. This means, > > if the CTR DRBG is selected and AES-NI is present, + * both the CTR DRBG > > and the selected cmac(aes) use AES-NI. > > + * > > + * The security strengths of the DRBGs are all 256 bits according to > > + * SP800-57 section 5.6.1. > > + * > > + * This definition is allowed to be changed. > > + */ > > +#ifdef CONFIG_CRYPTO_DRBG_CTR > > +static unsigned int lrng_drbg_type = 0; > > +#elif defined CONFIG_CRYPTO_DRBG_HMAC > > +static unsigned int lrng_drbg_type = 1; > > +#elif defined CONFIG_CRYPTO_DRBG_HASH > > +static unsigned int lrng_drbg_type = 2; > > +#else > > +#error "Unknown DRBG in use" > > +#endif > > + > > +/* The parameter must be r/o in sysfs as otherwise races appear. */ > > +module_param(lrng_drbg_type, uint, 0444); > > +MODULE_PARM_DESC(lrng_drbg_type, "DRBG type used for LRNG (0->CTR_DRBG, " > > + "1->HMAC_DRBG, 2->Hash_DRBG)"); > > One line for the string, please, not split. Changed Thank you. Ciao Stephan
