| Message ID | c65e43cc6a8c60877a183cdea5c9f7e43b8a4434.1624364386.git-series.a.fatoum@pengutronix.de |
|---|---|
| State | Superseded |
| Headers | show |
| Series | KEYS: trusted: Introduce support for NXP CAAM-based trusted keys | expand |
Hello Horia, Hello Aymen, On 22.06.21 14:37, Ahmad Fatoum wrote: > The 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. Are you ok with this patch and security/keys/trusted-keys/trusted_caam.c introduced in the follow-up commit? Cheers, Ahmad > > 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: Udit Agarwal <udit.agarwal@nxp.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: 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; > + > + if (len > CAAM_DESC_BYTES_MAX) > + return NULL; > + > + return kzalloc(len, GFP_KERNEL | GFP_DMA); > +} > + > +int caam_encap_blob(struct caam_blob_priv *priv, const char *keymod, > + void *input, void *output, size_t length) > +{ > + u32 *desc; > + struct device *jrdev = &priv->jrdev; > + dma_addr_t dma_in, dma_out; > + struct caam_blob_job_result testres; > + size_t keymod_len = strlen(keymod); > + int ret; > + > + if (length <= CAAM_BLOB_OVERHEAD || keymod_len > CAAM_BLOB_KEYMOD_LENGTH) > + return -EINVAL; > + > + desc = caam_blob_alloc_desc(keymod_len); > + if (!desc) { > + dev_err(jrdev, "unable to allocate desc\n"); > + return -ENOMEM; > + } > + > + dma_in = dma_map_single(jrdev, input, length - CAAM_BLOB_OVERHEAD, DMA_TO_DEVICE); > + if (dma_mapping_error(jrdev, dma_in)) { > + dev_err(jrdev, "unable to map input DMA buffer\n"); > + ret = -ENOMEM; > + goto out_free; > + } > + > + dma_out = dma_map_single(jrdev, output, length, DMA_FROM_DEVICE); > + if (dma_mapping_error(jrdev, dma_out)) { > + dev_err(jrdev, "unable to map output DMA buffer\n"); > + ret = -ENOMEM; > + goto out_unmap_in; > + } > + > + /* > + * A data blob is encrypted using a blob key (BK); a random number. > + * The BK is used as an AES-CCM key. The initial block (B0) and the > + * initial counter (Ctr0) are generated automatically and stored in > + * Class 1 Context DWords 0+1+2+3. The random BK is stored in the > + * Class 1 Key Register. Operation Mode is set to AES-CCM. > + */ > + > + init_job_desc(desc, 0); > + append_key_as_imm(desc, keymod, keymod_len, keymod_len, > + CLASS_2 | KEY_DEST_CLASS_REG); > + append_seq_in_ptr_intlen(desc, dma_in, length - CAAM_BLOB_OVERHEAD, 0); > + append_seq_out_ptr_intlen(desc, dma_out, length, 0); > + append_operation(desc, OP_TYPE_ENCAP_PROTOCOL | OP_PCLID_BLOB); > + > + print_hex_dump_debug("data@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, input, > + length - CAAM_BLOB_OVERHEAD, false); > + print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, desc, > + desc_bytes(desc), false); > + > + testres.err = 0; > + init_completion(&testres.completion); > + > + ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres); > + if (ret == -EINPROGRESS) { > + wait_for_completion(&testres.completion); > + ret = testres.err; > + print_hex_dump_debug("output@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, output, > + length, false); > + } > + > + dma_unmap_single(jrdev, dma_out, length, DMA_FROM_DEVICE); > +out_unmap_in: > + dma_unmap_single(jrdev, dma_in, length - CAAM_BLOB_OVERHEAD, DMA_TO_DEVICE); > +out_free: > + kfree(desc); > + > + return ret; > +} > +EXPORT_SYMBOL(caam_encap_blob); > + > +int caam_decap_blob(struct caam_blob_priv *priv, const char *keymod, > + void *input, void *output, size_t length) > +{ > + u32 *desc; > + struct device *jrdev = &priv->jrdev; > + dma_addr_t dma_in, dma_out; > + struct caam_blob_job_result testres; > + size_t keymod_len = strlen(keymod); > + int ret; > + > + if (length <= CAAM_BLOB_OVERHEAD || keymod_len > CAAM_BLOB_KEYMOD_LENGTH) > + return -EINVAL; > + > + desc = caam_blob_alloc_desc(keymod_len); > + if (!desc) { > + dev_err(jrdev, "unable to allocate desc\n"); > + return -ENOMEM; > + } > + > + dma_in = dma_map_single(jrdev, input, length, DMA_TO_DEVICE); > + if (dma_mapping_error(jrdev, dma_in)) { > + dev_err(jrdev, "unable to map input DMA buffer\n"); > + ret = -ENOMEM; > + goto out_free; > + } > + > + dma_out = dma_map_single(jrdev, output, length - CAAM_BLOB_OVERHEAD, DMA_FROM_DEVICE); > + if (dma_mapping_error(jrdev, dma_out)) { > + dev_err(jrdev, "unable to map output DMA buffer\n"); > + ret = -ENOMEM; > + goto out_unmap_in; > + } > + > + /* > + * A data blob is encrypted using a blob key (BK); a random number. > + * The BK is used as an AES-CCM key. The initial block (B0) and the > + * initial counter (Ctr0) are generated automatically and stored in > + * Class 1 Context DWords 0+1+2+3. The random BK is stored in the > + * Class 1 Key Register. Operation Mode is set to AES-CCM. > + */ > + > + init_job_desc(desc, 0); > + append_key_as_imm(desc, keymod, keymod_len, keymod_len, > + CLASS_2 | KEY_DEST_CLASS_REG); > + append_seq_in_ptr(desc, dma_in, length, 0); > + append_seq_out_ptr(desc, dma_out, length - CAAM_BLOB_OVERHEAD, 0); > + append_operation(desc, OP_TYPE_DECAP_PROTOCOL | OP_PCLID_BLOB); > + > + print_hex_dump_debug("data@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, input, > + length, false); > + print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, desc, > + desc_bytes(desc), false); > + > + testres.err = 0; > + init_completion(&testres.completion); > + > + ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres); > + if (ret == -EINPROGRESS) { > + wait_for_completion(&testres.completion); > + ret = testres.err; > + print_hex_dump_debug("output@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, output, > + length - CAAM_BLOB_OVERHEAD, false); > + } > + > + dma_unmap_single(jrdev, dma_out, length - CAAM_BLOB_OVERHEAD, DMA_FROM_DEVICE); > +out_unmap_in: > + dma_unmap_single(jrdev, dma_in, length, DMA_TO_DEVICE); > +out_free: > + kfree(desc); > + > + return ret; > +} > +EXPORT_SYMBOL(caam_decap_blob); > + > +struct caam_blob_priv *caam_blob_gen_init(void) > +{ > + struct device *jrdev; > + > + jrdev = caam_jr_alloc(); > + if (IS_ERR(jrdev)) > + return ERR_CAST(jrdev); > + > + return container_of(jrdev, struct caam_blob_priv, jrdev); > +} > +EXPORT_SYMBOL(caam_blob_gen_init); > + > +void caam_blob_gen_exit(struct caam_blob_priv *priv) > +{ > + caam_jr_free(&priv->jrdev); > +} > +EXPORT_SYMBOL(caam_blob_gen_exit); > diff --git a/include/soc/fsl/caam-blob.h b/include/soc/fsl/caam-blob.h > new file mode 100644 > index 000000000000..aebbc9335f64 > --- /dev/null > +++ b/include/soc/fsl/caam-blob.h > @@ -0,0 +1,56 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> > + */ > + > +#ifndef __CAAM_BLOB_GEN > +#define __CAAM_BLOB_GEN > + > +#include <linux/types.h> > + > +#define CAAM_BLOB_KEYMOD_LENGTH 16 > +#define CAAM_BLOB_OVERHEAD (32 + 16) > +#define CAAM_BLOB_MAX_LEN 4096 > + > +struct caam_blob_priv; > + > +/** caam_blob_gen_init - initialize blob generation > + * > + * returns either pointer to new caam_blob_priv instance > + * or error pointer > + */ > +struct caam_blob_priv *caam_blob_gen_init(void); > + > +/** caam_blob_gen_init - free blob generation resources > + * > + * @priv: instance returned by caam_blob_gen_init > + */ > +void caam_blob_gen_exit(struct caam_blob_priv *priv); > + > +/** caam_encap_blob - encapsulate blob > + * > + * @priv: instance returned by caam_blob_gen_init > + * @keymod: string to use as key modifier for blob encapsulation > + * can't be longer than CAAM_BLOB_KEYMOD_LENGTH > + * @input: buffer which CAAM will DMA from > + * @output: buffer which CAAM will DMA to > + * @length: buffer length including blob overhead > + * CAAM_BLOB_OVERHEAD < length <= CAAM_BLOB_MAX_LEN > + */ > +int caam_encap_blob(struct caam_blob_priv *priv, const char *keymod, > + void *input, void *output, size_t length); > + > +/** caam_decap_blob - decapsulate blob > + * > + * @priv: instance returned by caam_blob_gen_init > + * @keymod: string to use as key modifier for blob decapsulation > + * can't be longer than CAAM_BLOB_KEYMOD_LENGTH > + * @input: buffer which CAAM will DMA from > + * @output: buffer which CAAM will DMA to > + * @length: buffer length including blob overhead > + * CAAM_BLOB_OVERHEAD < length <= CAAM_BLOB_MAX_LEN > + */ > +int caam_decap_blob(struct caam_blob_priv *priv, const char *keymod, > + void *input, void *output, size_t length); > + > +#endif > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
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; + + if (len > CAAM_DESC_BYTES_MAX) + return NULL; + + return kzalloc(len, GFP_KERNEL | GFP_DMA); +} + +int caam_encap_blob(struct caam_blob_priv *priv, const char *keymod, + void *input, void *output, size_t length) +{ + u32 *desc; + struct device *jrdev = &priv->jrdev; + dma_addr_t dma_in, dma_out; + struct caam_blob_job_result testres; + size_t keymod_len = strlen(keymod); + int ret; + + if (length <= CAAM_BLOB_OVERHEAD || keymod_len > CAAM_BLOB_KEYMOD_LENGTH) + return -EINVAL; + + desc = caam_blob_alloc_desc(keymod_len); + if (!desc) { + dev_err(jrdev, "unable to allocate desc\n"); + return -ENOMEM; + } + + dma_in = dma_map_single(jrdev, input, length - CAAM_BLOB_OVERHEAD, DMA_TO_DEVICE); + if (dma_mapping_error(jrdev, dma_in)) { + dev_err(jrdev, "unable to map input DMA buffer\n"); + ret = -ENOMEM; + goto out_free; + } + + dma_out = dma_map_single(jrdev, output, length, DMA_FROM_DEVICE); + if (dma_mapping_error(jrdev, dma_out)) { + dev_err(jrdev, "unable to map output DMA buffer\n"); + ret = -ENOMEM; + goto out_unmap_in; + } + + /* + * A data blob is encrypted using a blob key (BK); a random number. + * The BK is used as an AES-CCM key. The initial block (B0) and the + * initial counter (Ctr0) are generated automatically and stored in + * Class 1 Context DWords 0+1+2+3. The random BK is stored in the + * Class 1 Key Register. Operation Mode is set to AES-CCM. + */ + + init_job_desc(desc, 0); + append_key_as_imm(desc, keymod, keymod_len, keymod_len, + CLASS_2 | KEY_DEST_CLASS_REG); + append_seq_in_ptr_intlen(desc, dma_in, length - CAAM_BLOB_OVERHEAD, 0); + append_seq_out_ptr_intlen(desc, dma_out, length, 0); + append_operation(desc, OP_TYPE_ENCAP_PROTOCOL | OP_PCLID_BLOB); + + print_hex_dump_debug("data@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, input, + length - CAAM_BLOB_OVERHEAD, false); + print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, desc, + desc_bytes(desc), false); + + testres.err = 0; + init_completion(&testres.completion); + + ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres); + if (ret == -EINPROGRESS) { + wait_for_completion(&testres.completion); + ret = testres.err; + print_hex_dump_debug("output@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, output, + length, false); + } + + dma_unmap_single(jrdev, dma_out, length, DMA_FROM_DEVICE); +out_unmap_in: + dma_unmap_single(jrdev, dma_in, length - CAAM_BLOB_OVERHEAD, DMA_TO_DEVICE); +out_free: + kfree(desc); + + return ret; +} +EXPORT_SYMBOL(caam_encap_blob); + +int caam_decap_blob(struct caam_blob_priv *priv, const char *keymod, + void *input, void *output, size_t length) +{ + u32 *desc; + struct device *jrdev = &priv->jrdev; + dma_addr_t dma_in, dma_out; + struct caam_blob_job_result testres; + size_t keymod_len = strlen(keymod); + int ret; + + if (length <= CAAM_BLOB_OVERHEAD || keymod_len > CAAM_BLOB_KEYMOD_LENGTH) + return -EINVAL; + + desc = caam_blob_alloc_desc(keymod_len); + if (!desc) { + dev_err(jrdev, "unable to allocate desc\n"); + return -ENOMEM; + } + + dma_in = dma_map_single(jrdev, input, length, DMA_TO_DEVICE); + if (dma_mapping_error(jrdev, dma_in)) { + dev_err(jrdev, "unable to map input DMA buffer\n"); + ret = -ENOMEM; + goto out_free; + } + + dma_out = dma_map_single(jrdev, output, length - CAAM_BLOB_OVERHEAD, DMA_FROM_DEVICE); + if (dma_mapping_error(jrdev, dma_out)) { + dev_err(jrdev, "unable to map output DMA buffer\n"); + ret = -ENOMEM; + goto out_unmap_in; + } + + /* + * A data blob is encrypted using a blob key (BK); a random number. + * The BK is used as an AES-CCM key. The initial block (B0) and the + * initial counter (Ctr0) are generated automatically and stored in + * Class 1 Context DWords 0+1+2+3. The random BK is stored in the + * Class 1 Key Register. Operation Mode is set to AES-CCM. + */ + + init_job_desc(desc, 0); + append_key_as_imm(desc, keymod, keymod_len, keymod_len, + CLASS_2 | KEY_DEST_CLASS_REG); + append_seq_in_ptr(desc, dma_in, length, 0); + append_seq_out_ptr(desc, dma_out, length - CAAM_BLOB_OVERHEAD, 0); + append_operation(desc, OP_TYPE_DECAP_PROTOCOL | OP_PCLID_BLOB); + + print_hex_dump_debug("data@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, input, + length, false); + print_hex_dump_debug("jobdesc@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, desc, + desc_bytes(desc), false); + + testres.err = 0; + init_completion(&testres.completion); + + ret = caam_jr_enqueue(jrdev, desc, caam_blob_job_done, &testres); + if (ret == -EINPROGRESS) { + wait_for_completion(&testres.completion); + ret = testres.err; + print_hex_dump_debug("output@"__stringify(__LINE__)": ", + DUMP_PREFIX_ADDRESS, 16, 1, output, + length - CAAM_BLOB_OVERHEAD, false); + } + + dma_unmap_single(jrdev, dma_out, length - CAAM_BLOB_OVERHEAD, DMA_FROM_DEVICE); +out_unmap_in: + dma_unmap_single(jrdev, dma_in, length, DMA_TO_DEVICE); +out_free: + kfree(desc); + + return ret; +} +EXPORT_SYMBOL(caam_decap_blob); + +struct caam_blob_priv *caam_blob_gen_init(void) +{ + struct device *jrdev; + + jrdev = caam_jr_alloc(); + if (IS_ERR(jrdev)) + return ERR_CAST(jrdev); + + return container_of(jrdev, struct caam_blob_priv, jrdev); +} +EXPORT_SYMBOL(caam_blob_gen_init); + +void caam_blob_gen_exit(struct caam_blob_priv *priv) +{ + caam_jr_free(&priv->jrdev); +} +EXPORT_SYMBOL(caam_blob_gen_exit); diff --git a/include/soc/fsl/caam-blob.h b/include/soc/fsl/caam-blob.h new file mode 100644 index 000000000000..aebbc9335f64 --- /dev/null +++ b/include/soc/fsl/caam-blob.h @@ -0,0 +1,56 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 Pengutronix, Ahmad Fatoum <kernel@pengutronix.de> + */ + +#ifndef __CAAM_BLOB_GEN +#define __CAAM_BLOB_GEN + +#include <linux/types.h> + +#define CAAM_BLOB_KEYMOD_LENGTH 16 +#define CAAM_BLOB_OVERHEAD (32 + 16) +#define CAAM_BLOB_MAX_LEN 4096 + +struct caam_blob_priv; + +/** caam_blob_gen_init - initialize blob generation + * + * returns either pointer to new caam_blob_priv instance + * or error pointer + */ +struct caam_blob_priv *caam_blob_gen_init(void); + +/** caam_blob_gen_init - free blob generation resources + * + * @priv: instance returned by caam_blob_gen_init + */ +void caam_blob_gen_exit(struct caam_blob_priv *priv); + +/** caam_encap_blob - encapsulate blob + * + * @priv: instance returned by caam_blob_gen_init + * @keymod: string to use as key modifier for blob encapsulation + * can't be longer than CAAM_BLOB_KEYMOD_LENGTH + * @input: buffer which CAAM will DMA from + * @output: buffer which CAAM will DMA to + * @length: buffer length including blob overhead + * CAAM_BLOB_OVERHEAD < length <= CAAM_BLOB_MAX_LEN + */ +int caam_encap_blob(struct caam_blob_priv *priv, const char *keymod, + void *input, void *output, size_t length); + +/** caam_decap_blob - decapsulate blob + * + * @priv: instance returned by caam_blob_gen_init + * @keymod: string to use as key modifier for blob decapsulation + * can't be longer than CAAM_BLOB_KEYMOD_LENGTH + * @input: buffer which CAAM will DMA from + * @output: buffer which CAAM will DMA to + * @length: buffer length including blob overhead + * CAAM_BLOB_OVERHEAD < length <= CAAM_BLOB_MAX_LEN + */ +int caam_decap_blob(struct caam_blob_priv *priv, const char *keymod, + void *input, void *output, size_t length); + +#endif
The 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. 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: Udit Agarwal <udit.agarwal@nxp.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: 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