| Message ID | 20220222195819.2313913-6-a.fatoum@pengutronix.de (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | KEYS: trusted: Introduce support for NXP CAAM-based trusted keys | expand |
Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> > -----Original Message----- > From: Ahmad Fatoum <a.fatoum@pengutronix.de> > Sent: Wednesday, February 23, 2022 1:28 AM > To: Jonathan Corbet <corbet@lwn.net>; David Howells > <dhowells@redhat.com>; Jarkko Sakkinen <jarkko@kernel.org>; James > Bottomley <jejb@linux.ibm.com>; Mimi Zohar <zohar@linux.ibm.com> > Cc: kernel@pengutronix.de; David Gstir <david@sigma-star.at>; > tharvey@gateworks.com; Matthias Schiffer <matthias.schiffer@ew.tq- > group.com>; Ahmad Fatoum <a.fatoum@pengutronix.de>; James Morris > <jmorris@namei.org>; Serge E. Hallyn <serge@hallyn.com>; 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>; > Eric Biggers <ebiggers@kernel.org>; Jan Luebbe <j.luebbe@pengutronix.de>; > Richard Weinberger <richard@nod.at>; Franck Lenormand > <franck.lenormand@nxp.com>; Sumit Garg <sumit.garg@linaro.org>; Pankaj > Gupta <pankaj.gupta@nxp.com>; keyrings@vger.kernel.org; linux- > crypto@vger.kernel.org; linux-doc@vger.kernel.org; linux- > integrity@vger.kernel.org; linux-kernel@vger.kernel.org; linux-security- > module@vger.kernel.org > Subject: [EXT] [PATCH v5 5/5] KEYS: trusted: Introduce support for NXP CAAM- > based trusted keys > > Caution: EXT Email > > The Cryptographic Acceleration and Assurance Module (CAAM) is an IP core built > into many newer i.MX and QorIQ SoCs by NXP. > > The CAAM does crypto acceleration, hardware number generation and has a > blob mechanism for encapsulation/decapsulation of sensitive material. > > This blob mechanism depends on a device specific random 256-bit One Time > Programmable Master Key that is fused in each SoC at manufacturing time. This > key is unreadable and can only be used by the CAAM for AES > encryption/decryption of user data. > > This makes it a suitable backend (source) for kernel trusted keys. > > Previous commits generalized trusted keys to support multiple backends and > added an API to access the CAAM blob mechanism. Based on these, provide the > necessary glue to use the CAAM for trusted keys. > > Reviewed-by: David Gstir <david@sigma-star.at> > Tested-By: Tim Harvey <tharvey@gateworks.com> > Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > --- > To: Jonathan Corbet <corbet@lwn.net> > To: David Howells <dhowells@redhat.com> > To: Jarkko Sakkinen <jarkko@kernel.org> > To: James Bottomley <jejb@linux.ibm.com> > To: Mimi Zohar <zohar@linux.ibm.com> > Cc: James Morris <jmorris@namei.org> > Cc: "Serge E. Hallyn" <serge@hallyn.com> > Cc: "Horia Geantă" <horia.geanta@nxp.com> > Cc: Aymen Sghaier <aymen.sghaier@nxp.com> > Cc: Herbert Xu <herbert@gondor.apana.org.au> > Cc: "David S. Miller" <davem@davemloft.net> > Cc: Eric Biggers <ebiggers@kernel.org> > 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: keyrings@vger.kernel.org > Cc: linux-crypto@vger.kernel.org > Cc: linux-doc@vger.kernel.org > Cc: linux-integrity@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: linux-security-module@vger.kernel.org > --- > .../admin-guide/kernel-parameters.txt | 1 + > .../security/keys/trusted-encrypted.rst | 40 +++++++++- > MAINTAINERS | 9 +++ > include/keys/trusted_caam.h | 11 +++ > security/keys/trusted-keys/Kconfig | 11 ++- > security/keys/trusted-keys/Makefile | 2 + > security/keys/trusted-keys/trusted_caam.c | 74 +++++++++++++++++++ > security/keys/trusted-keys/trusted_core.c | 6 +- > 8 files changed, 151 insertions(+), 3 deletions(-) create mode 100644 > include/keys/trusted_caam.h create mode 100644 security/keys/trusted- > keys/trusted_caam.c > > diff --git a/Documentation/admin-guide/kernel-parameters.txt > b/Documentation/admin-guide/kernel-parameters.txt > index 844c883ca9d8..9e7ef4c6585d 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -5875,6 +5875,7 @@ > sources: > - "tpm" > - "tee" > + - "caam" > If not specified then it defaults to iterating through > the trust source list starting with TPM and assigns the > first trust source as a backend which is initialized diff --git > a/Documentation/security/keys/trusted-encrypted.rst > b/Documentation/security/keys/trusted-encrypted.rst > index 99cf34d7c025..ed60c48cb692 100644 > --- a/Documentation/security/keys/trusted-encrypted.rst > +++ b/Documentation/security/keys/trusted-encrypted.rst > @@ -35,6 +35,13 @@ safe. > Rooted to Hardware Unique Key (HUK) which is generally burnt in on-chip > fuses and is accessible to TEE only. > > + (3) CAAM (Cryptographic Acceleration and Assurance Module: IP on > + NXP SoCs) > + > + When High Assurance Boot (HAB) is enabled and the CAAM is in secure > + mode, trust is rooted to the OTPMK, a never-disclosed 256-bit key > + randomly generated and fused into each SoC at manufacturing time. > + Otherwise, a common fixed test key is used instead. > + > * Execution isolation > > (1) TPM > @@ -46,6 +53,10 @@ safe. > Customizable set of operations running in isolated execution > environment verified via Secure/Trusted boot process. > > + (3) CAAM > + > + Fixed set of operations running in isolated execution environment. > + > * Optional binding to platform integrity state > > (1) TPM > @@ -63,6 +74,11 @@ safe. > Relies on Secure/Trusted boot process for platform integrity. It can > be extended with TEE based measured boot process. > > + (3) CAAM > + > + Relies on the High Assurance Boot (HAB) mechanism of NXP SoCs > + for platform integrity. > + > * Interfaces and APIs > > (1) TPM > @@ -74,10 +90,13 @@ safe. > TEEs have well-documented, standardized client interface and APIs. For > more details refer to ``Documentation/staging/tee.rst``. > > + (3) CAAM > + > + Interface is specific to silicon vendor. > > * Threat model > > - The strength and appropriateness of a particular TPM or TEE for a given > + The strength and appropriateness of a particular trust source for > + a given > purpose must be assessed when using them to protect security-relevant data. > > > @@ -104,6 +123,12 @@ selected trust source: > from platform specific hardware RNG or a software based Fortuna CSPRNG > which can be seeded via multiple entropy sources. > > + * CAAM: Kernel RNG > + > + The normal kernel random number generator is used. To seed it from the > + CAAM HWRNG, enable CRYPTO_DEV_FSL_CAAM_RNG_API and ensure the > device > + is probed. > + > Users may override this by specifying ``trusted.rng=kernel`` on the kernel > command-line to override the used RNG with the kernel's random number pool. > > @@ -192,6 +217,19 @@ Usage:: > specific to TEE device implementation. The key length for new keys is always in > bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). > > +Trusted Keys usage: CAAM > +------------------------ > + > +Usage:: > + > + keyctl add trusted name "new keylen" ring > + keyctl add trusted name "load hex_blob" ring > + keyctl print keyid > + > +"keyctl print" returns an ASCII hex copy of the sealed key, which is in > +format specific to CAAM device implementation. The key length for new > +keys is always in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). > + > Encrypted Keys usage > -------------------- > > diff --git a/MAINTAINERS b/MAINTAINERS > index f670002134e0..6eca4476bb76 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -10655,6 +10655,15 @@ S: Supported > F: include/keys/trusted_tee.h > F: security/keys/trusted-keys/trusted_tee.c > > +KEYS-TRUSTED-CAAM > +M: Ahmad Fatoum <a.fatoum@pengutronix.de> > +R: Pengutronix Kernel Team <kernel@pengutronix.de> > +L: linux-integrity@vger.kernel.org > +L: keyrings@vger.kernel.org > +S: Maintained > +F: include/keys/trusted_caam.h > +F: security/keys/trusted-keys/trusted_caam.c > + > KEYS/KEYRINGS > M: David Howells <dhowells@redhat.com> > M: Jarkko Sakkinen <jarkko@kernel.org> > diff --git a/include/keys/trusted_caam.h b/include/keys/trusted_caam.h new file > mode 100644 index 000000000000..2fba0996b0b0 > --- /dev/null > +++ b/include/keys/trusted_caam.h > @@ -0,0 +1,11 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> > +*/ > + > +#ifndef __CAAM_TRUSTED_KEY_H > +#define __CAAM_TRUSTED_KEY_H > + > +extern struct trusted_key_ops caam_trusted_key_ops; > + > +#endif > diff --git a/security/keys/trusted-keys/Kconfig b/security/keys/trusted- > keys/Kconfig > index fc4abd581abb..dbfdd8536468 100644 > --- a/security/keys/trusted-keys/Kconfig > +++ b/security/keys/trusted-keys/Kconfig > @@ -24,6 +24,15 @@ config TRUSTED_KEYS_TEE > Enable use of the Trusted Execution Environment (TEE) as trusted > key backend. > > -if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE > +config TRUSTED_KEYS_CAAM > + bool "CAAM-based trusted keys" > + depends on CRYPTO_DEV_FSL_CAAM_JR >= TRUSTED_KEYS > + select CRYPTO_DEV_FSL_CAAM_BLOB_GEN > + default y > + help > + Enable use of NXP's Cryptographic Accelerator and Assurance Module > + (CAAM) as trusted key backend. > + > +if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE && !TRUSTED_KEYS_CAAM > comment "No trust source selected!" > endif > diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted- > keys/Makefile > index 2e2371eae4d5..735aa0bc08ef 100644 > --- a/security/keys/trusted-keys/Makefile > +++ b/security/keys/trusted-keys/Makefile > @@ -12,3 +12,5 @@ trusted-$(CONFIG_TRUSTED_KEYS_TPM) += > trusted_tpm2.o > trusted-$(CONFIG_TRUSTED_KEYS_TPM) += tpm2key.asn1.o > > trusted-$(CONFIG_TRUSTED_KEYS_TEE) += trusted_tee.o > + > +trusted-$(CONFIG_TRUSTED_KEYS_CAAM) += trusted_caam.o > diff --git a/security/keys/trusted-keys/trusted_caam.c b/security/keys/trusted- > keys/trusted_caam.c > new file mode 100644 > index 000000000000..066f08d6eb2c > --- /dev/null > +++ b/security/keys/trusted-keys/trusted_caam.c > @@ -0,0 +1,74 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> > +*/ > + > +#include <keys/trusted_caam.h> > +#include <keys/trusted-type.h> > +#include <linux/build_bug.h> > +#include <linux/key-type.h> > +#include <soc/fsl/caam-blob.h> > + > +static struct caam_blob_priv *blobifier; > + > +#define KEYMOD "SECURE_KEY" > + > +static_assert(MAX_KEY_SIZE + CAAM_BLOB_OVERHEAD <= > CAAM_BLOB_MAX_LEN); > +static_assert(MAX_BLOB_SIZE <= CAAM_BLOB_MAX_LEN); > + > +static int trusted_caam_seal(struct trusted_key_payload *p, char > +*datablob) { > + int length = p->key_len + CAAM_BLOB_OVERHEAD; > + int ret; > + > + ret = caam_encap_blob(blobifier, KEYMOD, p->key, p->blob, length); > + if (ret) > + return ret; > + > + p->blob_len = length; > + return 0; > +} > + > +static int trusted_caam_unseal(struct trusted_key_payload *p, char > +*datablob) { > + int length = p->blob_len; > + int ret; > + > + ret = caam_decap_blob(blobifier, KEYMOD, p->blob, p->key, length); > + if (ret) > + return ret; > + > + p->key_len = length - CAAM_BLOB_OVERHEAD; > + return 0; > +} > + > +static int trusted_caam_init(void) > +{ > + int ret; > + > + blobifier = caam_blob_gen_init(); > + if (IS_ERR(blobifier)) { > + pr_err("Job Ring Device allocation for transform failed\n"); > + return PTR_ERR(blobifier); > + } > + > + ret = register_key_type(&key_type_trusted); > + if (ret) > + caam_blob_gen_exit(blobifier); > + > + return ret; > +} > + > +static void trusted_caam_exit(void) > +{ > + unregister_key_type(&key_type_trusted); > + caam_blob_gen_exit(blobifier); > +} > + > +struct trusted_key_ops caam_trusted_key_ops = { > + .migratable = 0, /* non-migratable */ > + .init = trusted_caam_init, > + .seal = trusted_caam_seal, > + .unseal = trusted_caam_unseal, > + .exit = trusted_caam_exit, > +}; > diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted- > keys/trusted_core.c > index 9235fb7d0ec9..640434cd437a 100644 > --- a/security/keys/trusted-keys/trusted_core.c > +++ b/security/keys/trusted-keys/trusted_core.c > @@ -9,6 +9,7 @@ > #include <keys/user-type.h> > #include <keys/trusted-type.h> > #include <keys/trusted_tee.h> > +#include <keys/trusted_caam.h> > #include <keys/trusted_tpm.h> > #include <linux/capability.h> > #include <linux/err.h> > @@ -29,7 +30,7 @@ MODULE_PARM_DESC(rng, "Select trusted key RNG"); > > static char *trusted_key_source; > module_param_named(source, trusted_key_source, charp, 0); - > MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)"); > +MODULE_PARM_DESC(source, "Select trusted keys source (tpm, tee or > +caam)"); > > static const struct trusted_key_source trusted_key_sources[] = { #if > defined(CONFIG_TRUSTED_KEYS_TPM) @@ -38,6 +39,9 @@ static const struct > trusted_key_source trusted_key_sources[] = { #if > defined(CONFIG_TRUSTED_KEYS_TEE) > { "tee", &trusted_key_tee_ops }, #endif > +#if defined(CONFIG_TRUSTED_KEYS_CAAM) > + { "caam", &caam_trusted_key_ops }, #endif > }; > > DEFINE_STATIC_CALL_NULL(trusted_key_init, *trusted_key_sources[0].ops- > >init); > -- > 2.30.2
Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> > -----Original Message----- > From: Ahmad Fatoum <a.fatoum@pengutronix.de> > Sent: Wednesday, February 23, 2022 1:28 AM > To: Jonathan Corbet <corbet@lwn.net>; David Howells > <dhowells@redhat.com>; Jarkko Sakkinen <jarkko@kernel.org>; James > Bottomley <jejb@linux.ibm.com>; Mimi Zohar <zohar@linux.ibm.com> > Cc: kernel@pengutronix.de; David Gstir <david@sigma-star.at>; > tharvey@gateworks.com; Matthias Schiffer <matthias.schiffer@ew.tq- > group.com>; Ahmad Fatoum <a.fatoum@pengutronix.de>; James Morris > <jmorris@namei.org>; Serge E. Hallyn <serge@hallyn.com>; 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>; Eric Biggers <ebiggers@kernel.org>; Jan Luebbe > <j.luebbe@pengutronix.de>; Richard Weinberger <richard@nod.at>; Franck > Lenormand <franck.lenormand@nxp.com>; Sumit Garg > <sumit.garg@linaro.org>; Pankaj Gupta <pankaj.gupta@nxp.com>; > keyrings@vger.kernel.org; linux-crypto@vger.kernel.org; linux- > doc@vger.kernel.org; linux-integrity@vger.kernel.org; linux- > kernel@vger.kernel.org; linux-security-module@vger.kernel.org > Subject: [EXT] [PATCH v5 5/5] KEYS: trusted: Introduce support for NXP > CAAM-based trusted keys > > Caution: EXT Email > > The Cryptographic Acceleration and Assurance Module (CAAM) is an IP core > built into many newer i.MX and QorIQ SoCs by NXP. > > The CAAM does crypto acceleration, hardware number generation and has a > blob mechanism for encapsulation/decapsulation of sensitive material. > > This blob mechanism depends on a device specific random 256-bit One Time > Programmable Master Key that is fused in each SoC at manufacturing time. > This key is unreadable and can only be used by the CAAM for AES > encryption/decryption of user data. > > This makes it a suitable backend (source) for kernel trusted keys. > > Previous commits generalized trusted keys to support multiple backends and > added an API to access the CAAM blob mechanism. Based on these, provide > the necessary glue to use the CAAM for trusted keys. > > Reviewed-by: David Gstir <david@sigma-star.at> > Tested-By: Tim Harvey <tharvey@gateworks.com> > Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > --- > To: Jonathan Corbet <corbet@lwn.net> > To: David Howells <dhowells@redhat.com> > To: Jarkko Sakkinen <jarkko@kernel.org> > To: James Bottomley <jejb@linux.ibm.com> > To: Mimi Zohar <zohar@linux.ibm.com> > Cc: James Morris <jmorris@namei.org> > Cc: "Serge E. Hallyn" <serge@hallyn.com> > Cc: "Horia Geantă" <horia.geanta@nxp.com> > Cc: Aymen Sghaier <aymen.sghaier@nxp.com> > Cc: Herbert Xu <herbert@gondor.apana.org.au> > Cc: "David S. Miller" <davem@davemloft.net> > Cc: Eric Biggers <ebiggers@kernel.org> > 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: keyrings@vger.kernel.org > Cc: linux-crypto@vger.kernel.org > Cc: linux-doc@vger.kernel.org > Cc: linux-integrity@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: linux-security-module@vger.kernel.org > --- > .../admin-guide/kernel-parameters.txt | 1 + > .../security/keys/trusted-encrypted.rst | 40 +++++++++- > MAINTAINERS | 9 +++ > include/keys/trusted_caam.h | 11 +++ > security/keys/trusted-keys/Kconfig | 11 ++- > security/keys/trusted-keys/Makefile | 2 + > security/keys/trusted-keys/trusted_caam.c | 74 +++++++++++++++++++ > security/keys/trusted-keys/trusted_core.c | 6 +- > 8 files changed, 151 insertions(+), 3 deletions(-) create mode 100644 > include/keys/trusted_caam.h create mode 100644 security/keys/trusted- > keys/trusted_caam.c > > diff --git a/Documentation/admin-guide/kernel-parameters.txt > b/Documentation/admin-guide/kernel-parameters.txt > index 844c883ca9d8..9e7ef4c6585d 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -5875,6 +5875,7 @@ > sources: > - "tpm" > - "tee" > + - "caam" > If not specified then it defaults to iterating through > the trust source list starting with TPM and assigns the > first trust source as a backend which is initialized diff --git > a/Documentation/security/keys/trusted-encrypted.rst > b/Documentation/security/keys/trusted-encrypted.rst > index 99cf34d7c025..ed60c48cb692 100644 > --- a/Documentation/security/keys/trusted-encrypted.rst > +++ b/Documentation/security/keys/trusted-encrypted.rst > @@ -35,6 +35,13 @@ safe. > Rooted to Hardware Unique Key (HUK) which is generally burnt in on- > chip > fuses and is accessible to TEE only. > > + (3) CAAM (Cryptographic Acceleration and Assurance Module: IP on > + NXP SoCs) > + > + When High Assurance Boot (HAB) is enabled and the CAAM is in secure > + mode, trust is rooted to the OTPMK, a never-disclosed 256-bit key > + randomly generated and fused into each SoC at manufacturing time. > + Otherwise, a common fixed test key is used instead. > + > * Execution isolation > > (1) TPM > @@ -46,6 +53,10 @@ safe. > Customizable set of operations running in isolated execution > environment verified via Secure/Trusted boot process. > > + (3) CAAM > + > + Fixed set of operations running in isolated execution environment. > + > * Optional binding to platform integrity state > > (1) TPM > @@ -63,6 +74,11 @@ safe. > Relies on Secure/Trusted boot process for platform integrity. It can > be extended with TEE based measured boot process. > > + (3) CAAM > + > + Relies on the High Assurance Boot (HAB) mechanism of NXP SoCs > + for platform integrity. > + > * Interfaces and APIs > > (1) TPM > @@ -74,10 +90,13 @@ safe. > TEEs have well-documented, standardized client interface and APIs. For > more details refer to ``Documentation/staging/tee.rst``. > > + (3) CAAM > + > + Interface is specific to silicon vendor. > > * Threat model > > - The strength and appropriateness of a particular TPM or TEE for a given > + The strength and appropriateness of a particular trust source for > + a given > purpose must be assessed when using them to protect security-relevant > data. > > > @@ -104,6 +123,12 @@ selected trust source: > from platform specific hardware RNG or a software based Fortuna > CSPRNG > which can be seeded via multiple entropy sources. > > + * CAAM: Kernel RNG > + > + The normal kernel random number generator is used. To seed it from the > + CAAM HWRNG, enable CRYPTO_DEV_FSL_CAAM_RNG_API and ensure > the device > + is probed. > + > Users may override this by specifying ``trusted.rng=kernel`` on the kernel > command-line to override the used RNG with the kernel's random number > pool. > > @@ -192,6 +217,19 @@ Usage:: > specific to TEE device implementation. The key length for new keys is always > in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). > > +Trusted Keys usage: CAAM > +------------------------ > + > +Usage:: > + > + keyctl add trusted name "new keylen" ring > + keyctl add trusted name "load hex_blob" ring > + keyctl print keyid > + > +"keyctl print" returns an ASCII hex copy of the sealed key, which is in > +format specific to CAAM device implementation. The key length for new > +keys is always in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). > + > Encrypted Keys usage > -------------------- > > diff --git a/MAINTAINERS b/MAINTAINERS > index f670002134e0..6eca4476bb76 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -10655,6 +10655,15 @@ S: Supported > F: include/keys/trusted_tee.h > F: security/keys/trusted-keys/trusted_tee.c > > +KEYS-TRUSTED-CAAM > +M: Ahmad Fatoum <a.fatoum@pengutronix.de> > +R: Pengutronix Kernel Team <kernel@pengutronix.de> > +L: linux-integrity@vger.kernel.org > +L: keyrings@vger.kernel.org > +S: Maintained > +F: include/keys/trusted_caam.h > +F: security/keys/trusted-keys/trusted_caam.c > + > KEYS/KEYRINGS > M: David Howells <dhowells@redhat.com> > M: Jarkko Sakkinen <jarkko@kernel.org> > diff --git a/include/keys/trusted_caam.h b/include/keys/trusted_caam.h > new file mode 100644 index 000000000000..2fba0996b0b0 > --- /dev/null > +++ b/include/keys/trusted_caam.h > @@ -0,0 +1,11 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> > +*/ > + > +#ifndef __CAAM_TRUSTED_KEY_H > +#define __CAAM_TRUSTED_KEY_H > + > +extern struct trusted_key_ops caam_trusted_key_ops; > + > +#endif > diff --git a/security/keys/trusted-keys/Kconfig b/security/keys/trusted- > keys/Kconfig > index fc4abd581abb..dbfdd8536468 100644 > --- a/security/keys/trusted-keys/Kconfig > +++ b/security/keys/trusted-keys/Kconfig > @@ -24,6 +24,15 @@ config TRUSTED_KEYS_TEE > Enable use of the Trusted Execution Environment (TEE) as trusted > key backend. > > -if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE > +config TRUSTED_KEYS_CAAM > + bool "CAAM-based trusted keys" > + depends on CRYPTO_DEV_FSL_CAAM_JR >= TRUSTED_KEYS > + select CRYPTO_DEV_FSL_CAAM_BLOB_GEN > + default y > + help > + Enable use of NXP's Cryptographic Accelerator and Assurance Module > + (CAAM) as trusted key backend. > + > +if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE > && !TRUSTED_KEYS_CAAM > comment "No trust source selected!" > endif > diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted- > keys/Makefile > index 2e2371eae4d5..735aa0bc08ef 100644 > --- a/security/keys/trusted-keys/Makefile > +++ b/security/keys/trusted-keys/Makefile > @@ -12,3 +12,5 @@ trusted-$(CONFIG_TRUSTED_KEYS_TPM) += > trusted_tpm2.o > trusted-$(CONFIG_TRUSTED_KEYS_TPM) += tpm2key.asn1.o > > trusted-$(CONFIG_TRUSTED_KEYS_TEE) += trusted_tee.o > + > +trusted-$(CONFIG_TRUSTED_KEYS_CAAM) += trusted_caam.o > diff --git a/security/keys/trusted-keys/trusted_caam.c > b/security/keys/trusted-keys/trusted_caam.c > new file mode 100644 > index 000000000000..066f08d6eb2c > --- /dev/null > +++ b/security/keys/trusted-keys/trusted_caam.c > @@ -0,0 +1,74 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> > +*/ > + > +#include <keys/trusted_caam.h> > +#include <keys/trusted-type.h> > +#include <linux/build_bug.h> > +#include <linux/key-type.h> > +#include <soc/fsl/caam-blob.h> > + > +static struct caam_blob_priv *blobifier; > + > +#define KEYMOD "SECURE_KEY" > + > +static_assert(MAX_KEY_SIZE + CAAM_BLOB_OVERHEAD <= > CAAM_BLOB_MAX_LEN); > +static_assert(MAX_BLOB_SIZE <= CAAM_BLOB_MAX_LEN); > + > +static int trusted_caam_seal(struct trusted_key_payload *p, char > +*datablob) { > + int length = p->key_len + CAAM_BLOB_OVERHEAD; > + int ret; > + > + ret = caam_encap_blob(blobifier, KEYMOD, p->key, p->blob, length); > + if (ret) > + return ret; > + > + p->blob_len = length; > + return 0; > +} > + > +static int trusted_caam_unseal(struct trusted_key_payload *p, char > +*datablob) { > + int length = p->blob_len; > + int ret; > + > + ret = caam_decap_blob(blobifier, KEYMOD, p->blob, p->key, length); > + if (ret) > + return ret; > + > + p->key_len = length - CAAM_BLOB_OVERHEAD; > + return 0; > +} > + > +static int trusted_caam_init(void) > +{ > + int ret; > + > + blobifier = caam_blob_gen_init(); > + if (IS_ERR(blobifier)) { > + pr_err("Job Ring Device allocation for transform failed\n"); > + return PTR_ERR(blobifier); > + } > + > + ret = register_key_type(&key_type_trusted); > + if (ret) > + caam_blob_gen_exit(blobifier); > + > + return ret; > +} > + > +static void trusted_caam_exit(void) > +{ > + unregister_key_type(&key_type_trusted); > + caam_blob_gen_exit(blobifier); > +} > + > +struct trusted_key_ops caam_trusted_key_ops = { > + .migratable = 0, /* non-migratable */ > + .init = trusted_caam_init, > + .seal = trusted_caam_seal, > + .unseal = trusted_caam_unseal, > + .exit = trusted_caam_exit, > +}; > diff --git a/security/keys/trusted-keys/trusted_core.c > b/security/keys/trusted-keys/trusted_core.c > index 9235fb7d0ec9..640434cd437a 100644 > --- a/security/keys/trusted-keys/trusted_core.c > +++ b/security/keys/trusted-keys/trusted_core.c > @@ -9,6 +9,7 @@ > #include <keys/user-type.h> > #include <keys/trusted-type.h> > #include <keys/trusted_tee.h> > +#include <keys/trusted_caam.h> > #include <keys/trusted_tpm.h> > #include <linux/capability.h> > #include <linux/err.h> > @@ -29,7 +30,7 @@ MODULE_PARM_DESC(rng, "Select trusted key RNG"); > > static char *trusted_key_source; > module_param_named(source, trusted_key_source, charp, 0); - > MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)"); > +MODULE_PARM_DESC(source, "Select trusted keys source (tpm, tee or > +caam)"); > > static const struct trusted_key_source trusted_key_sources[] = { #if > defined(CONFIG_TRUSTED_KEYS_TPM) @@ -38,6 +39,9 @@ static const > struct trusted_key_source trusted_key_sources[] = { #if > defined(CONFIG_TRUSTED_KEYS_TEE) > { "tee", &trusted_key_tee_ops }, #endif > +#if defined(CONFIG_TRUSTED_KEYS_CAAM) > + { "caam", &caam_trusted_key_ops }, #endif > }; > > DEFINE_STATIC_CALL_NULL(trusted_key_init, > *trusted_key_sources[0].ops->init); > -- > 2.30.2
Tested-by: Pankaj Gupta <pankaj.gupta@nxp.com> Testing Details with iMX8 platform: - Using command "keyctl", successfully able to create/load key from the @s keyring. - Able to use the key with DM-Crypt utility. - Across power cycle, Validated the decrypted content with correct key; as well as the incorrect key. Regards Pankaj > -----Original Message----- > From: Pankaj Gupta <pankaj.gupta@nxp.com> > Sent: Wednesday, March 2, 2022 10:08 AM > To: Ahmad Fatoum <a.fatoum@pengutronix.de>; Jonathan Corbet > <corbet@lwn.net>; David Howells <dhowells@redhat.com>; Jarkko Sakkinen > <jarkko@kernel.org>; James Bottomley <jejb@linux.ibm.com>; Mimi Zohar > <zohar@linux.ibm.com> > Cc: kernel@pengutronix.de; David Gstir <david@sigma-star.at>; > tharvey@gateworks.com; Matthias Schiffer <matthias.schiffer@ew.tq- > group.com>; James Morris <jmorris@namei.org>; Serge E. Hallyn > <serge@hallyn.com>; 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>; > Eric Biggers <ebiggers@kernel.org>; Jan Luebbe <j.luebbe@pengutronix.de>; > Richard Weinberger <richard@nod.at>; Franck Lenormand > <franck.lenormand@nxp.com>; Sumit Garg <sumit.garg@linaro.org>; > keyrings@vger.kernel.org; linux-crypto@vger.kernel.org; linux- > doc@vger.kernel.org; linux-integrity@vger.kernel.org; linux- > kernel@vger.kernel.org; linux-security-module@vger.kernel.org > Subject: RE: [EXT] [PATCH v5 5/5] KEYS: trusted: Introduce support for NXP > CAAM-based trusted keys > > Caution: EXT Email > > Reviewed-by: Pankaj Gupta <pankaj.gupta@nxp.com> > > > -----Original Message----- > > From: Ahmad Fatoum <a.fatoum@pengutronix.de> > > Sent: Wednesday, February 23, 2022 1:28 AM > > To: Jonathan Corbet <corbet@lwn.net>; David Howells > > <dhowells@redhat.com>; Jarkko Sakkinen <jarkko@kernel.org>; James > > Bottomley <jejb@linux.ibm.com>; Mimi Zohar <zohar@linux.ibm.com> > > Cc: kernel@pengutronix.de; David Gstir <david@sigma-star.at>; > > tharvey@gateworks.com; Matthias Schiffer <matthias.schiffer@ew.tq- > > group.com>; Ahmad Fatoum <a.fatoum@pengutronix.de>; James Morris > > <jmorris@namei.org>; Serge E. Hallyn <serge@hallyn.com>; 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>; Eric Biggers <ebiggers@kernel.org>; Jan Luebbe > > <j.luebbe@pengutronix.de>; Richard Weinberger <richard@nod.at>; > Franck > > Lenormand <franck.lenormand@nxp.com>; Sumit Garg > > <sumit.garg@linaro.org>; Pankaj Gupta <pankaj.gupta@nxp.com>; > > keyrings@vger.kernel.org; linux-crypto@vger.kernel.org; linux- > > doc@vger.kernel.org; linux-integrity@vger.kernel.org; linux- > > kernel@vger.kernel.org; linux-security-module@vger.kernel.org > > Subject: [EXT] [PATCH v5 5/5] KEYS: trusted: Introduce support for NXP > > CAAM-based trusted keys > > > > Caution: EXT Email > > > > The Cryptographic Acceleration and Assurance Module (CAAM) is an IP > > core built into many newer i.MX and QorIQ SoCs by NXP. > > > > The CAAM does crypto acceleration, hardware number generation and has > > a blob mechanism for encapsulation/decapsulation of sensitive material. > > > > This blob mechanism depends on a device specific random 256-bit One > > Time Programmable Master Key that is fused in each SoC at manufacturing > time. > > This key is unreadable and can only be used by the CAAM for AES > > encryption/decryption of user data. > > > > This makes it a suitable backend (source) for kernel trusted keys. > > > > Previous commits generalized trusted keys to support multiple backends > > and added an API to access the CAAM blob mechanism. Based on these, > > provide the necessary glue to use the CAAM for trusted keys. > > > > Reviewed-by: David Gstir <david@sigma-star.at> > > Tested-By: Tim Harvey <tharvey@gateworks.com> > > Tested-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com> > > Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de> > > --- > > To: Jonathan Corbet <corbet@lwn.net> > > To: David Howells <dhowells@redhat.com> > > To: Jarkko Sakkinen <jarkko@kernel.org> > > To: James Bottomley <jejb@linux.ibm.com> > > To: Mimi Zohar <zohar@linux.ibm.com> > > Cc: James Morris <jmorris@namei.org> > > Cc: "Serge E. Hallyn" <serge@hallyn.com> > > Cc: "Horia Geantă" <horia.geanta@nxp.com> > > Cc: Aymen Sghaier <aymen.sghaier@nxp.com> > > Cc: Herbert Xu <herbert@gondor.apana.org.au> > > Cc: "David S. Miller" <davem@davemloft.net> > > Cc: Eric Biggers <ebiggers@kernel.org> > > 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: keyrings@vger.kernel.org > > Cc: linux-crypto@vger.kernel.org > > Cc: linux-doc@vger.kernel.org > > Cc: linux-integrity@vger.kernel.org > > Cc: linux-kernel@vger.kernel.org > > Cc: linux-security-module@vger.kernel.org > > --- > > .../admin-guide/kernel-parameters.txt | 1 + > > .../security/keys/trusted-encrypted.rst | 40 +++++++++- > > MAINTAINERS | 9 +++ > > include/keys/trusted_caam.h | 11 +++ > > security/keys/trusted-keys/Kconfig | 11 ++- > > security/keys/trusted-keys/Makefile | 2 + > > security/keys/trusted-keys/trusted_caam.c | 74 > +++++++++++++++++++ > > security/keys/trusted-keys/trusted_core.c | 6 +- > > 8 files changed, 151 insertions(+), 3 deletions(-) create mode > > 100644 include/keys/trusted_caam.h create mode 100644 > > security/keys/trusted- keys/trusted_caam.c > > > > diff --git a/Documentation/admin-guide/kernel-parameters.txt > > b/Documentation/admin-guide/kernel-parameters.txt > > index 844c883ca9d8..9e7ef4c6585d 100644 > > --- a/Documentation/admin-guide/kernel-parameters.txt > > +++ b/Documentation/admin-guide/kernel-parameters.txt > > @@ -5875,6 +5875,7 @@ > > sources: > > - "tpm" > > - "tee" > > + - "caam" > > If not specified then it defaults to iterating through > > the trust source list starting with TPM and assigns the > > first trust source as a backend which is > > initialized diff --git > > a/Documentation/security/keys/trusted-encrypted.rst > > b/Documentation/security/keys/trusted-encrypted.rst > > index 99cf34d7c025..ed60c48cb692 100644 > > --- a/Documentation/security/keys/trusted-encrypted.rst > > +++ b/Documentation/security/keys/trusted-encrypted.rst > > @@ -35,6 +35,13 @@ safe. > > Rooted to Hardware Unique Key (HUK) which is generally burnt > > in on- chip > > fuses and is accessible to TEE only. > > > > + (3) CAAM (Cryptographic Acceleration and Assurance Module: IP on > > + NXP SoCs) > > + > > + When High Assurance Boot (HAB) is enabled and the CAAM is in > secure > > + mode, trust is rooted to the OTPMK, a never-disclosed 256-bit key > > + randomly generated and fused into each SoC at manufacturing time. > > + Otherwise, a common fixed test key is used instead. > > + > > * Execution isolation > > > > (1) TPM > > @@ -46,6 +53,10 @@ safe. > > Customizable set of operations running in isolated execution > > environment verified via Secure/Trusted boot process. > > > > + (3) CAAM > > + > > + Fixed set of operations running in isolated execution environment. > > + > > * Optional binding to platform integrity state > > > > (1) TPM > > @@ -63,6 +74,11 @@ safe. > > Relies on Secure/Trusted boot process for platform integrity. It can > > be extended with TEE based measured boot process. > > > > + (3) CAAM > > + > > + Relies on the High Assurance Boot (HAB) mechanism of NXP SoCs > > + for platform integrity. > > + > > * Interfaces and APIs > > > > (1) TPM > > @@ -74,10 +90,13 @@ safe. > > TEEs have well-documented, standardized client interface and APIs. > For > > more details refer to ``Documentation/staging/tee.rst``. > > > > + (3) CAAM > > + > > + Interface is specific to silicon vendor. > > > > * Threat model > > > > - The strength and appropriateness of a particular TPM or TEE for a given > > + The strength and appropriateness of a particular trust source > > + for a given > > purpose must be assessed when using them to protect > > security-relevant data. > > > > > > @@ -104,6 +123,12 @@ selected trust source: > > from platform specific hardware RNG or a software based Fortuna > > CSPRNG > > which can be seeded via multiple entropy sources. > > > > + * CAAM: Kernel RNG > > + > > + The normal kernel random number generator is used. To seed it from > the > > + CAAM HWRNG, enable CRYPTO_DEV_FSL_CAAM_RNG_API and > ensure > > the device > > + is probed. > > + > > Users may override this by specifying ``trusted.rng=kernel`` on the > > kernel command-line to override the used RNG with the kernel's random > > number pool. > > > > @@ -192,6 +217,19 @@ Usage:: > > specific to TEE device implementation. The key length for new keys > > is always in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). > > > > +Trusted Keys usage: CAAM > > +------------------------ > > + > > +Usage:: > > + > > + keyctl add trusted name "new keylen" ring > > + keyctl add trusted name "load hex_blob" ring > > + keyctl print keyid > > + > > +"keyctl print" returns an ASCII hex copy of the sealed key, which is > > +in format specific to CAAM device implementation. The key length for > > +new keys is always in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 > bits). > > + > > Encrypted Keys usage > > -------------------- > > > > diff --git a/MAINTAINERS b/MAINTAINERS index > > f670002134e0..6eca4476bb76 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -10655,6 +10655,15 @@ S: Supported > > F: include/keys/trusted_tee.h > > F: security/keys/trusted-keys/trusted_tee.c > > > > +KEYS-TRUSTED-CAAM > > +M: Ahmad Fatoum <a.fatoum@pengutronix.de> > > +R: Pengutronix Kernel Team <kernel@pengutronix.de> > > +L: linux-integrity@vger.kernel.org > > +L: keyrings@vger.kernel.org > > +S: Maintained > > +F: include/keys/trusted_caam.h > > +F: security/keys/trusted-keys/trusted_caam.c > > + > > KEYS/KEYRINGS > > M: David Howells <dhowells@redhat.com> > > M: Jarkko Sakkinen <jarkko@kernel.org> > > diff --git a/include/keys/trusted_caam.h b/include/keys/trusted_caam.h > > new file mode 100644 index 000000000000..2fba0996b0b0 > > --- /dev/null > > +++ b/include/keys/trusted_caam.h > > @@ -0,0 +1,11 @@ > > +/* SPDX-License-Identifier: GPL-2.0-only */ > > +/* > > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum > > +<kernel@pengutronix.de> */ > > + > > +#ifndef __CAAM_TRUSTED_KEY_H > > +#define __CAAM_TRUSTED_KEY_H > > + > > +extern struct trusted_key_ops caam_trusted_key_ops; > > + > > +#endif > > diff --git a/security/keys/trusted-keys/Kconfig > > b/security/keys/trusted- keys/Kconfig index fc4abd581abb..dbfdd8536468 > > 100644 > > --- a/security/keys/trusted-keys/Kconfig > > +++ b/security/keys/trusted-keys/Kconfig > > @@ -24,6 +24,15 @@ config TRUSTED_KEYS_TEE > > Enable use of the Trusted Execution Environment (TEE) as trusted > > key backend. > > > > -if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE > > +config TRUSTED_KEYS_CAAM > > + bool "CAAM-based trusted keys" > > + depends on CRYPTO_DEV_FSL_CAAM_JR >= TRUSTED_KEYS > > + select CRYPTO_DEV_FSL_CAAM_BLOB_GEN > > + default y > > + help > > + Enable use of NXP's Cryptographic Accelerator and Assurance Module > > + (CAAM) as trusted key backend. > > + > > +if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE > > && !TRUSTED_KEYS_CAAM > > comment "No trust source selected!" > > endif > > diff --git a/security/keys/trusted-keys/Makefile > > b/security/keys/trusted- keys/Makefile index > > 2e2371eae4d5..735aa0bc08ef 100644 > > --- a/security/keys/trusted-keys/Makefile > > +++ b/security/keys/trusted-keys/Makefile > > @@ -12,3 +12,5 @@ trusted-$(CONFIG_TRUSTED_KEYS_TPM) += > trusted_tpm2.o > > trusted-$(CONFIG_TRUSTED_KEYS_TPM) += tpm2key.asn1.o > > > > trusted-$(CONFIG_TRUSTED_KEYS_TEE) += trusted_tee.o > > + > > +trusted-$(CONFIG_TRUSTED_KEYS_CAAM) += trusted_caam.o > > diff --git a/security/keys/trusted-keys/trusted_caam.c > > b/security/keys/trusted-keys/trusted_caam.c > > new file mode 100644 > > index 000000000000..066f08d6eb2c > > --- /dev/null > > +++ b/security/keys/trusted-keys/trusted_caam.c > > @@ -0,0 +1,74 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum > > +<kernel@pengutronix.de> */ > > + > > +#include <keys/trusted_caam.h> > > +#include <keys/trusted-type.h> > > +#include <linux/build_bug.h> > > +#include <linux/key-type.h> > > +#include <soc/fsl/caam-blob.h> > > + > > +static struct caam_blob_priv *blobifier; > > + > > +#define KEYMOD "SECURE_KEY" > > + > > +static_assert(MAX_KEY_SIZE + CAAM_BLOB_OVERHEAD <= > > CAAM_BLOB_MAX_LEN); > > +static_assert(MAX_BLOB_SIZE <= CAAM_BLOB_MAX_LEN); > > + > > +static int trusted_caam_seal(struct trusted_key_payload *p, char > > +*datablob) { > > + int length = p->key_len + CAAM_BLOB_OVERHEAD; > > + int ret; > > + > > + ret = caam_encap_blob(blobifier, KEYMOD, p->key, p->blob, length); > > + if (ret) > > + return ret; > > + > > + p->blob_len = length; > > + return 0; > > +} > > + > > +static int trusted_caam_unseal(struct trusted_key_payload *p, char > > +*datablob) { > > + int length = p->blob_len; > > + int ret; > > + > > + ret = caam_decap_blob(blobifier, KEYMOD, p->blob, p->key, length); > > + if (ret) > > + return ret; > > + > > + p->key_len = length - CAAM_BLOB_OVERHEAD; > > + return 0; > > +} > > + > > +static int trusted_caam_init(void) > > +{ > > + int ret; > > + > > + blobifier = caam_blob_gen_init(); > > + if (IS_ERR(blobifier)) { > > + pr_err("Job Ring Device allocation for transform failed\n"); > > + return PTR_ERR(blobifier); > > + } > > + > > + ret = register_key_type(&key_type_trusted); > > + if (ret) > > + caam_blob_gen_exit(blobifier); > > + > > + return ret; > > +} > > + > > +static void trusted_caam_exit(void) > > +{ > > + unregister_key_type(&key_type_trusted); > > + caam_blob_gen_exit(blobifier); } > > + > > +struct trusted_key_ops caam_trusted_key_ops = { > > + .migratable = 0, /* non-migratable */ > > + .init = trusted_caam_init, > > + .seal = trusted_caam_seal, > > + .unseal = trusted_caam_unseal, > > + .exit = trusted_caam_exit, > > +}; > > diff --git a/security/keys/trusted-keys/trusted_core.c > > b/security/keys/trusted-keys/trusted_core.c > > index 9235fb7d0ec9..640434cd437a 100644 > > --- a/security/keys/trusted-keys/trusted_core.c > > +++ b/security/keys/trusted-keys/trusted_core.c > > @@ -9,6 +9,7 @@ > > #include <keys/user-type.h> > > #include <keys/trusted-type.h> > > #include <keys/trusted_tee.h> > > +#include <keys/trusted_caam.h> > > #include <keys/trusted_tpm.h> > > #include <linux/capability.h> > > #include <linux/err.h> > > @@ -29,7 +30,7 @@ MODULE_PARM_DESC(rng, "Select trusted key RNG"); > > > > static char *trusted_key_source; > > module_param_named(source, trusted_key_source, charp, 0); - > > MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)"); > > +MODULE_PARM_DESC(source, "Select trusted keys source (tpm, tee or > > +caam)"); > > > > static const struct trusted_key_source trusted_key_sources[] = { #if > > defined(CONFIG_TRUSTED_KEYS_TPM) @@ -38,6 +39,9 @@ static const > struct > > trusted_key_source trusted_key_sources[] = { #if > > defined(CONFIG_TRUSTED_KEYS_TEE) > > { "tee", &trusted_key_tee_ops }, #endif > > +#if defined(CONFIG_TRUSTED_KEYS_CAAM) > > + { "caam", &caam_trusted_key_ops }, #endif > > }; > > > > DEFINE_STATIC_CALL_NULL(trusted_key_init, > > *trusted_key_sources[0].ops->init); > > -- > > 2.30.2
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 844c883ca9d8..9e7ef4c6585d 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5875,6 +5875,7 @@ sources: - "tpm" - "tee" + - "caam" If not specified then it defaults to iterating through the trust source list starting with TPM and assigns the first trust source as a backend which is initialized diff --git a/Documentation/security/keys/trusted-encrypted.rst b/Documentation/security/keys/trusted-encrypted.rst index 99cf34d7c025..ed60c48cb692 100644 --- a/Documentation/security/keys/trusted-encrypted.rst +++ b/Documentation/security/keys/trusted-encrypted.rst @@ -35,6 +35,13 @@ safe. Rooted to Hardware Unique Key (HUK) which is generally burnt in on-chip fuses and is accessible to TEE only. + (3) CAAM (Cryptographic Acceleration and Assurance Module: IP on NXP SoCs) + + When High Assurance Boot (HAB) is enabled and the CAAM is in secure + mode, trust is rooted to the OTPMK, a never-disclosed 256-bit key + randomly generated and fused into each SoC at manufacturing time. + Otherwise, a common fixed test key is used instead. + * Execution isolation (1) TPM @@ -46,6 +53,10 @@ safe. Customizable set of operations running in isolated execution environment verified via Secure/Trusted boot process. + (3) CAAM + + Fixed set of operations running in isolated execution environment. + * Optional binding to platform integrity state (1) TPM @@ -63,6 +74,11 @@ safe. Relies on Secure/Trusted boot process for platform integrity. It can be extended with TEE based measured boot process. + (3) CAAM + + Relies on the High Assurance Boot (HAB) mechanism of NXP SoCs + for platform integrity. + * Interfaces and APIs (1) TPM @@ -74,10 +90,13 @@ safe. TEEs have well-documented, standardized client interface and APIs. For more details refer to ``Documentation/staging/tee.rst``. + (3) CAAM + + Interface is specific to silicon vendor. * Threat model - The strength and appropriateness of a particular TPM or TEE for a given + The strength and appropriateness of a particular trust source for a given purpose must be assessed when using them to protect security-relevant data. @@ -104,6 +123,12 @@ selected trust source: from platform specific hardware RNG or a software based Fortuna CSPRNG which can be seeded via multiple entropy sources. + * CAAM: Kernel RNG + + The normal kernel random number generator is used. To seed it from the + CAAM HWRNG, enable CRYPTO_DEV_FSL_CAAM_RNG_API and ensure the device + is probed. + Users may override this by specifying ``trusted.rng=kernel`` on the kernel command-line to override the used RNG with the kernel's random number pool. @@ -192,6 +217,19 @@ Usage:: specific to TEE device implementation. The key length for new keys is always in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). +Trusted Keys usage: CAAM +------------------------ + +Usage:: + + keyctl add trusted name "new keylen" ring + keyctl add trusted name "load hex_blob" ring + keyctl print keyid + +"keyctl print" returns an ASCII hex copy of the sealed key, which is in format +specific to CAAM device implementation. The key length for new keys is always +in bytes. Trusted Keys can be 32 - 128 bytes (256 - 1024 bits). + Encrypted Keys usage -------------------- diff --git a/MAINTAINERS b/MAINTAINERS index f670002134e0..6eca4476bb76 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10655,6 +10655,15 @@ S: Supported F: include/keys/trusted_tee.h F: security/keys/trusted-keys/trusted_tee.c +KEYS-TRUSTED-CAAM +M: Ahmad Fatoum <a.fatoum@pengutronix.de> +R: Pengutronix Kernel Team <kernel@pengutronix.de> +L: linux-integrity@vger.kernel.org +L: keyrings@vger.kernel.org +S: Maintained +F: include/keys/trusted_caam.h +F: security/keys/trusted-keys/trusted_caam.c + KEYS/KEYRINGS M: David Howells <dhowells@redhat.com> M: Jarkko Sakkinen <jarkko@kernel.org> diff --git a/include/keys/trusted_caam.h b/include/keys/trusted_caam.h new file mode 100644 index 000000000000..2fba0996b0b0 --- /dev/null +++ b/include/keys/trusted_caam.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> + */ + +#ifndef __CAAM_TRUSTED_KEY_H +#define __CAAM_TRUSTED_KEY_H + +extern struct trusted_key_ops caam_trusted_key_ops; + +#endif diff --git a/security/keys/trusted-keys/Kconfig b/security/keys/trusted-keys/Kconfig index fc4abd581abb..dbfdd8536468 100644 --- a/security/keys/trusted-keys/Kconfig +++ b/security/keys/trusted-keys/Kconfig @@ -24,6 +24,15 @@ config TRUSTED_KEYS_TEE Enable use of the Trusted Execution Environment (TEE) as trusted key backend. -if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE +config TRUSTED_KEYS_CAAM + bool "CAAM-based trusted keys" + depends on CRYPTO_DEV_FSL_CAAM_JR >= TRUSTED_KEYS + select CRYPTO_DEV_FSL_CAAM_BLOB_GEN + default y + help + Enable use of NXP's Cryptographic Accelerator and Assurance Module + (CAAM) as trusted key backend. + +if !TRUSTED_KEYS_TPM && !TRUSTED_KEYS_TEE && !TRUSTED_KEYS_CAAM comment "No trust source selected!" endif diff --git a/security/keys/trusted-keys/Makefile b/security/keys/trusted-keys/Makefile index 2e2371eae4d5..735aa0bc08ef 100644 --- a/security/keys/trusted-keys/Makefile +++ b/security/keys/trusted-keys/Makefile @@ -12,3 +12,5 @@ trusted-$(CONFIG_TRUSTED_KEYS_TPM) += trusted_tpm2.o trusted-$(CONFIG_TRUSTED_KEYS_TPM) += tpm2key.asn1.o trusted-$(CONFIG_TRUSTED_KEYS_TEE) += trusted_tee.o + +trusted-$(CONFIG_TRUSTED_KEYS_CAAM) += trusted_caam.o diff --git a/security/keys/trusted-keys/trusted_caam.c b/security/keys/trusted-keys/trusted_caam.c new file mode 100644 index 000000000000..066f08d6eb2c --- /dev/null +++ b/security/keys/trusted-keys/trusted_caam.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> + */ + +#include <keys/trusted_caam.h> +#include <keys/trusted-type.h> +#include <linux/build_bug.h> +#include <linux/key-type.h> +#include <soc/fsl/caam-blob.h> + +static struct caam_blob_priv *blobifier; + +#define KEYMOD "SECURE_KEY" + +static_assert(MAX_KEY_SIZE + CAAM_BLOB_OVERHEAD <= CAAM_BLOB_MAX_LEN); +static_assert(MAX_BLOB_SIZE <= CAAM_BLOB_MAX_LEN); + +static int trusted_caam_seal(struct trusted_key_payload *p, char *datablob) +{ + int length = p->key_len + CAAM_BLOB_OVERHEAD; + int ret; + + ret = caam_encap_blob(blobifier, KEYMOD, p->key, p->blob, length); + if (ret) + return ret; + + p->blob_len = length; + return 0; +} + +static int trusted_caam_unseal(struct trusted_key_payload *p, char *datablob) +{ + int length = p->blob_len; + int ret; + + ret = caam_decap_blob(blobifier, KEYMOD, p->blob, p->key, length); + if (ret) + return ret; + + p->key_len = length - CAAM_BLOB_OVERHEAD; + return 0; +} + +static int trusted_caam_init(void) +{ + int ret; + + blobifier = caam_blob_gen_init(); + if (IS_ERR(blobifier)) { + pr_err("Job Ring Device allocation for transform failed\n"); + return PTR_ERR(blobifier); + } + + ret = register_key_type(&key_type_trusted); + if (ret) + caam_blob_gen_exit(blobifier); + + return ret; +} + +static void trusted_caam_exit(void) +{ + unregister_key_type(&key_type_trusted); + caam_blob_gen_exit(blobifier); +} + +struct trusted_key_ops caam_trusted_key_ops = { + .migratable = 0, /* non-migratable */ + .init = trusted_caam_init, + .seal = trusted_caam_seal, + .unseal = trusted_caam_unseal, + .exit = trusted_caam_exit, +}; diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c index 9235fb7d0ec9..640434cd437a 100644 --- a/security/keys/trusted-keys/trusted_core.c +++ b/security/keys/trusted-keys/trusted_core.c @@ -9,6 +9,7 @@ #include <keys/user-type.h> #include <keys/trusted-type.h> #include <keys/trusted_tee.h> +#include <keys/trusted_caam.h> #include <keys/trusted_tpm.h> #include <linux/capability.h> #include <linux/err.h> @@ -29,7 +30,7 @@ MODULE_PARM_DESC(rng, "Select trusted key RNG"); static char *trusted_key_source; module_param_named(source, trusted_key_source, charp, 0); -MODULE_PARM_DESC(source, "Select trusted keys source (tpm or tee)"); +MODULE_PARM_DESC(source, "Select trusted keys source (tpm, tee or caam)"); static const struct trusted_key_source trusted_key_sources[] = { #if defined(CONFIG_TRUSTED_KEYS_TPM) @@ -38,6 +39,9 @@ static const struct trusted_key_source trusted_key_sources[] = { #if defined(CONFIG_TRUSTED_KEYS_TEE) { "tee", &trusted_key_tee_ops }, #endif +#if defined(CONFIG_TRUSTED_KEYS_CAAM) + { "caam", &caam_trusted_key_ops }, +#endif }; DEFINE_STATIC_CALL_NULL(trusted_key_init, *trusted_key_sources[0].ops->init);