Messages in this thread | | | From | Pankaj Gupta <> | Subject | RE: [EXT] Re: [PATCH v5 4/5] crypto: caam - add in-kernel interface for blob generator | Date | Fri, 25 Feb 2022 12:20:54 +0000 |
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> -----Original Message----- > From: Ahmad Fatoum <a.fatoum@pengutronix.de> > Sent: Wednesday, February 23, 2022 9:50 PM > To: Jarkko Sakkinen <jarkko@kernel.org> > Cc: Horia Geanta <horia.geanta@nxp.com>; Aymen Sghaier > <aymen.sghaier@nxp.com>; Herbert Xu <herbert@gondor.apana.org.au>; > David S. Miller <davem@davemloft.net>; kernel@pengutronix.de; David Gstir > <david@sigma-star.at>; Pankaj Gupta <pankaj.gupta@nxp.com>; > tharvey@gateworks.com; Matthias Schiffer <matthias.schiffer@ew.tq- > group.com>; James Bottomley <jejb@linux.ibm.com>; Mimi Zohar > <zohar@linux.ibm.com>; David Howells <dhowells@redhat.com>; James Morris > <jmorris@namei.org>; Eric Biggers <ebiggers@kernel.org>; Serge E. Hallyn > <serge@hallyn.com>; Jan Luebbe <j.luebbe@pengutronix.de>; Richard > Weinberger <richard@nod.at>; Franck Lenormand > <franck.lenormand@nxp.com>; Sumit Garg <sumit.garg@linaro.org>; linux- > integrity@vger.kernel.org; keyrings@vger.kernel.org; linux- > crypto@vger.kernel.org; linux-kernel@vger.kernel.org; linux-security- > module@vger.kernel.org > Subject: [EXT] Re: [PATCH v5 4/5] crypto: caam - add in-kernel interface for blob > generator > > Caution: EXT Email > > On 23.02.22 16:41, Jarkko Sakkinen wrote: > > On Tue, Feb 22, 2022 at 08:58:18PM +0100, Ahmad Fatoum wrote: > >> The NXP Cryptographic Acceleration and Assurance Module (CAAM) can be > >> used to protect user-defined data across system reboot: > >> > >> - When the system is fused and boots into secure state, the master > >> key is a unique never-disclosed device-specific key > >> - random key is encrypted by key derived from master key > >> - data is encrypted using the random key > >> - encrypted data and its encrypted random key are stored alongside > >> - This blob can now be safely stored in non-volatile memory > >> > >> On next power-on: > >> - blob is loaded into CAAM > >> - CAAM writes decrypted data either into memory or key register > >> > >> Add functions to realize encrypting and decrypting into memory > >> alongside the CAAM driver. > >> > >> They will be used in a later commit as a source for the trusted key > >> seal/unseal mechanism. > >> > >> Reviewed-by: David Gstir <david@sigma-star.at> > >> Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> > >> Tested-By: Tim Harvey <tharvey@gateworks.com> > >> Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > >> Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de> > >> Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > >> --- > >> To: "Horia Geantă" <horia.geanta@nxp.com> > >> To: Aymen Sghaier <aymen.sghaier@nxp.com> > >> To: Herbert Xu <herbert@gondor.apana.org.au> > >> To: "David S. Miller" <davem@davemloft.net> > >> Cc: James Bottomley <jejb@linux.ibm.com> > >> Cc: Jarkko Sakkinen <jarkko@kernel.org> > >> Cc: Mimi Zohar <zohar@linux.ibm.com> > >> Cc: David Howells <dhowells@redhat.com> > >> Cc: James Morris <jmorris@namei.org> > >> Cc: Eric Biggers <ebiggers@kernel.org> > >> Cc: "Serge E. Hallyn" <serge@hallyn.com> > >> Cc: Jan Luebbe <j.luebbe@pengutronix.de> > >> Cc: David Gstir <david@sigma-star.at> > >> Cc: Richard Weinberger <richard@nod.at> > >> Cc: Franck LENORMAND <franck.lenormand@nxp.com> > >> Cc: Sumit Garg <sumit.garg@linaro.org> > >> Cc: Tim Harvey <tharvey@gateworks.com> > >> Cc: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > >> Cc: Pankaj Gupta <pankaj.gupta@nxp.com> > >> Cc: linux-integrity@vger.kernel.org > >> Cc: keyrings@vger.kernel.org > >> Cc: linux-crypto@vger.kernel.org > >> Cc: linux-kernel@vger.kernel.org > >> Cc: linux-security-module@vger.kernel.org > >> --- > >> drivers/crypto/caam/Kconfig | 3 + > >> drivers/crypto/caam/Makefile | 1 + > >> drivers/crypto/caam/blob_gen.c | 230 > +++++++++++++++++++++++++++++++++ > >> include/soc/fsl/caam-blob.h | 56 ++++++++ > >> 4 files changed, 290 insertions(+) > >> create mode 100644 drivers/crypto/caam/blob_gen.c create mode > >> 100644 include/soc/fsl/caam-blob.h > >> > >> diff --git a/drivers/crypto/caam/Kconfig > >> b/drivers/crypto/caam/Kconfig index 84ea7cba5ee5..ea9f8b1ae981 100644 > >> --- a/drivers/crypto/caam/Kconfig > >> +++ b/drivers/crypto/caam/Kconfig > >> @@ -151,6 +151,9 @@ config CRYPTO_DEV_FSL_CAAM_RNG_API > >> Selecting this will register the SEC4 hardware rng to > >> the hw_random API for supplying the kernel entropy pool. > >> > >> +config CRYPTO_DEV_FSL_CAAM_BLOB_GEN > >> + bool > >> + > >> endif # CRYPTO_DEV_FSL_CAAM_JR > >> > >> endif # CRYPTO_DEV_FSL_CAAM > >> diff --git a/drivers/crypto/caam/Makefile > >> b/drivers/crypto/caam/Makefile index 3570286eb9ce..25f7ae5a4642 > >> 100644 > >> --- a/drivers/crypto/caam/Makefile > >> +++ b/drivers/crypto/caam/Makefile > >> @@ -21,6 +21,7 @@ caam_jr- > $(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) > >> += caamalg_qi.o > >> caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_AHASH_API) += caamhash.o > >> caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_RNG_API) += caamrng.o > >> caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_PKC_API) += caampkc.o > >> pkc_desc.o > >> +caam_jr-$(CONFIG_CRYPTO_DEV_FSL_CAAM_BLOB_GEN) += blob_gen.o > >> > >> caam-$(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI) += qi.o ifneq > >> ($(CONFIG_CRYPTO_DEV_FSL_CAAM_CRYPTO_API_QI),) > >> diff --git a/drivers/crypto/caam/blob_gen.c > >> b/drivers/crypto/caam/blob_gen.c new file mode 100644 index > >> 000000000000..513d3f90e438 > >> --- /dev/null > >> +++ b/drivers/crypto/caam/blob_gen.c > >> @@ -0,0 +1,230 @@ > >> +// SPDX-License-Identifier: GPL-2.0-only > >> +/* > >> + * Copyright (C) 2015 Pengutronix, Steffen Trumtrar > >> +<kernel@pengutronix.de> > >> + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum > >> +<kernel@pengutronix.de> */ > >> + > >> +#include <linux/device.h> > >> +#include <soc/fsl/caam-blob.h> > >> + > >> +#include "compat.h" > >> +#include "desc_constr.h" > >> +#include "desc.h" > >> +#include "error.h" > >> +#include "intern.h" > >> +#include "jr.h" > >> +#include "regs.h" > >> + > >> +struct caam_blob_priv { > >> + struct device jrdev; > >> +}; > >> + > >> +struct caam_blob_job_result { > >> + int err; > >> + struct completion completion; > >> +}; > >> + > >> +static void caam_blob_job_done(struct device *dev, u32 *desc, u32 > >> +err, void *context) { > >> + struct caam_blob_job_result *res = context; > >> + int ecode = 0; > >> + > >> + dev_dbg(dev, "%s %d: err 0x%x\n", __func__, __LINE__, err); > >> + > >> + if (err) > >> + ecode = caam_jr_strstatus(dev, err); > >> + > >> + res->err = ecode; > >> + > >> + /* > >> + * Upon completion, desc points to a buffer containing a CAAM job > >> + * descriptor which encapsulates data into an externally-storable > >> + * blob. > >> + */ > >> + complete(&res->completion); > >> +} > >> + > >> +static u32 *caam_blob_alloc_desc(size_t keymod_len) { > >> + size_t len; > >> + > >> + /* header + (key mod immediate) + 2x pointers + op */ > >> + len = 4 + (4 + ALIGN(keymod_len, 4)) + 2*(4 + 4 + > >> + CAAM_PTR_SZ_MAX) + 4; > > > > Nit: the amount of magic numbers is overwhelming here. I neither > > understand the statement nor how that comment should help me to > understand it. > > header = 4 > (key mod immediate) = (4 + ALIGN(keymod_len, 4)) > 2x pointer = 2 * (4 + 4 + CAAM_PTR_SZ_MAX) > op = 4
Instead of the function caam_blob_alloc_desc(), it will be great if the caller functions caam_encap_blob()/caam_encap_blob (), could add local array: uint32_t desc[CAAM_DESC_BYTES_MAX];
> > I haven't heard back from the CAAM maintainers yet since v1. Perhaps now is a > good occasion to chime in? :-) > > @Jarkko, could you take a look at patch 5? That's the gist of the series and I > have yet to get maintainer feedback on that one. > > Cheers, > Ahmad > > > > > > BR, Jarkko > > > > > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | > https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.pen > gutronix.de%2F&data=04%7C01%7Cpankaj.gupta%40nxp.com%7Cc97e9d4 > aaf304124407908d9f6e87101%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0% > 7C0%7C637812300459173929%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wL > jAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&s > data=CvnfIXR68DPRCaYrOYQKSv2eSBSNSSJYx2BQJee4yLg%3D&reserved=0 > | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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