Hi Ahmad, Suggested to define macro with more details. Please find comments in-line. Regards Pankaj > -----Original Message----- > From: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> > Sent: Wednesday, March 16, 2022 10:14 PM > To: Horia Geanta <horia.geanta@xxxxxxx>; Pankaj Gupta > <pankaj.gupta@xxxxxxx>; Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>; David > S. Miller <davem@xxxxxxxxxxxxx> > Cc: kernel@xxxxxxxxxxxxxx; David Gstir <david@xxxxxxxxxxxxx>; > tharvey@xxxxxxxxxxxxx; Matthias Schiffer <matthias.schiffer@xxxxx- > group.com>; Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>; James Bottomley > <jejb@xxxxxxxxxxxxx>; Jarkko Sakkinen <jarkko@xxxxxxxxxx>; Mimi Zohar > <zohar@xxxxxxxxxxxxx>; David Howells <dhowells@xxxxxxxxxx>; James Morris > <jmorris@xxxxxxxxx>; Eric Biggers <ebiggers@xxxxxxxxxx>; Serge E. Hallyn > <serge@xxxxxxxxxx>; Jan Luebbe <j.luebbe@xxxxxxxxxxxxxx>; Richard > Weinberger <richard@xxxxxx>; Franck Lenormand > <franck.lenormand@xxxxxxx>; Sumit Garg <sumit.garg@xxxxxxxxxx>; linux- > integrity@xxxxxxxxxxxxxxx; keyrings@xxxxxxxxxxxxxxx; linux- > crypto@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; linux-security- > module@xxxxxxxxxxxxxxx > Subject: [EXT] [PATCH v6 3/4] crypto: caam - add in-kernel interface for blob > generator > > Caution: EXT Email > > 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@xxxxxxxxxxxxx> > Reviewed-by: Pankaj Gupta <pankaj.gupta@xxxxxxx> > Tested-By: Tim Harvey <tharvey@xxxxxxxxxxxxx> > Tested-by: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx> > Signed-off-by: Steffen Trumtrar <s.trumtrar@xxxxxxxxxxxxxx> > Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx> > --- > v5 -> v6: > - Dropped caam_blob_alloc_desc() in favor of kzalloc() with fixed size. > This simplifies code and wastes at most 12 bytes which are freed > at the end of the function anyway. > - Factored out common code between caam_encap_blob and > caam_decap_blob > as both functions were largely identical > - use append_seq_(in|out)_ptr_intlen for both encap/decap as a result > - use reverse christmas tree order for caam_process_blob variable > definitions. > v4 -> v5: > - Collected Reviewed-by's and Tested-by's > - Note in CAAM patch what CAAM is (Jarkko) > v3 -> v4: > - Collected Acked-by's, Reviewed-by's and Tested-by > - Fixed typo spotted by David > v2 -> v3: > - No change > v1 -> v2: > - Enforce maximum keymod size (Horia) > - Use append_seq_(in|out)_ptr_intlen instead of append_seq_(in|out)_ptr > (Horia) > - Make blobifier handle private to CAAM glue code file (Horia) > > To: "Horia Geantă" <horia.geanta@xxxxxxx> > To: Pankaj Gupta <pankaj.gupta@xxxxxxx> > To: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx> > To: "David S. Miller" <davem@xxxxxxxxxxxxx> > Cc: James Bottomley <jejb@xxxxxxxxxxxxx> > Cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx> > Cc: Mimi Zohar <zohar@xxxxxxxxxxxxx> > Cc: David Howells <dhowells@xxxxxxxxxx> > Cc: James Morris <jmorris@xxxxxxxxx> > Cc: Eric Biggers <ebiggers@xxxxxxxxxx> > Cc: "Serge E. Hallyn" <serge@xxxxxxxxxx> > Cc: Jan Luebbe <j.luebbe@xxxxxxxxxxxxxx> > Cc: David Gstir <david@xxxxxxxxxxxxx> > Cc: Richard Weinberger <richard@xxxxxx> > Cc: Franck LENORMAND <franck.lenormand@xxxxxxx> > Cc: Matthias Schiffer <matthias.schiffer@xxxxxxxxxxxxxxx> > Cc: Sumit Garg <sumit.garg@xxxxxxxxxx> > Cc: linux-integrity@xxxxxxxxxxxxxxx > Cc: keyrings@xxxxxxxxxxxxxxx > Cc: linux-crypto@xxxxxxxxxxxxxxx > Cc: linux-kernel@xxxxxxxxxxxxxxx > Cc: linux-security-module@xxxxxxxxxxxxxxx > --- > drivers/crypto/caam/Kconfig | 3 + > drivers/crypto/caam/Makefile | 1 + > drivers/crypto/caam/blob_gen.c | 160 +++++++++++++++++++++++++++++++++ > include/soc/fsl/caam-blob.h | 79 ++++++++++++++++ > 4 files changed, 243 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..2564e63c8fe0 > --- /dev/null > +++ b/drivers/crypto/caam/blob_gen.c > @@ -0,0 +1,160 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2015 Pengutronix, Steffen Trumtrar > +<kernel@xxxxxxxxxxxxxx> > + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum <kernel@xxxxxxxxxxxxxx> > +*/ > + > +#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" > + len = 4 + (4 + ALIGN(keymod_len, 4)) + 2*(4 + 4 + >>>> + CAAM_PTR_SZ_MAX) + 4; > +/* header + (key mod immediate) + 2x seq_intlen pointers + op */ > +#define CAAM_BLOB_DESC_BYTES_MAX \ > + (CAAM_CMD_SZ + \ > + CAAM_CMD_SZ + CAAM_BLOB_KEYMOD_LENGTH + \ > + 2 * (CAAM_CMD_SZ + CAAM_PTR_SZ_MAX) + \ > + CAAM_CMD_SZ) > + Suggested to replace the above macro like below: +#define CAAM_BLOB_DESC_BYTES_MAX \ + (CAAM_CMD_SZ + \ /* Command to initialize & stating length of descriptor */ + CAAM_CMD_SZ + CAAM_BLOB_KEYMOD_LENGTH + \ /* Command to append the key-modifier + followed by the key-modifier data */ + (CAAM_CMD_SZ + CAAM_PTR_SZ_MAX) + \ /* Command to include input plain key and pointer to the input key */ + (CAAM_CMD_SZ + CAAM_PTR_SZ_MAX) + \ /* Command to include output-key blob and pointer to the output-key blob */ + CAAM_CMD_SZ) /* Command describing the Operation to perform */ > +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); > +} > + > +int caam_process_blob(struct caam_blob_priv *priv, bool encap, > + const char *keymod, void *input, void *output, > + size_t length) > +{ > + size_t in_len = length, out_len = length; > + struct caam_blob_job_result testres; > + struct device *jrdev = &priv->jrdev; > + dma_addr_t dma_in, dma_out; > + int op = OP_PCLID_BLOB; > + size_t keymod_len; > + u32 *desc; > + int ret; > + > + keymod_len = strlen(keymod); > + > + if (length <= CAAM_BLOB_OVERHEAD || keymod_len > > CAAM_BLOB_KEYMOD_LENGTH) > + return -EINVAL; > + > + if (encap) { > + op |= OP_TYPE_ENCAP_PROTOCOL; > + in_len -= CAAM_BLOB_OVERHEAD; > + } else { > + op |= OP_TYPE_DECAP_PROTOCOL; > + out_len -= CAAM_BLOB_OVERHEAD; > + } > + > + desc = kzalloc(CAAM_BLOB_DESC_BYTES_MAX, GFP_KERNEL | GFP_DMA); > + if (!desc) { > + dev_err(jrdev, "unable to allocate desc\n"); > + return -ENOMEM; > + } > + > + dma_in = dma_map_single(jrdev, input, in_len, 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, out_len, 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, in_len, 0); > + append_seq_out_ptr_intlen(desc, dma_out, out_len, 0); > + append_operation(desc, op); > + > + print_hex_dump_debug("data@"__stringify(__LINE__)": ", > + DUMP_PREFIX_ADDRESS, 16, 1, input, > + in_len, 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, > + out_len, false); > + } > + > + dma_unmap_single(jrdev, dma_out, out_len, DMA_FROM_DEVICE); > +out_unmap_in: > + dma_unmap_single(jrdev, dma_in, in_len, DMA_TO_DEVICE); > +out_free: > + kfree(desc); > + > + return ret; > +} > +EXPORT_SYMBOL(caam_process_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..2c4a05dc59cd > --- /dev/null > +++ b/include/soc/fsl/caam-blob.h > @@ -0,0 +1,79 @@ > +/* SPDX-License-Identifier: GPL-2.0-only */ > +/* > + * Copyright (C) 2020 Pengutronix, Ahmad Fatoum <kernel@xxxxxxxxxxxxxx> > +*/ > + > +#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_exit - free blob generation resources > + * > + * @priv: instance returned by caam_blob_gen_init */ void > +caam_blob_gen_exit(struct caam_blob_priv *priv); > + > +/** caam_process_blob - encapsulate or decapsulate blob > + * > + * @priv: instance returned by caam_blob_gen_init > + * @encap: true for encapsulation, false for decapsulation > + * @keymod: string to use as key modifier for blob capsulation > + * 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_process_blob(struct caam_blob_priv *priv, bool encap, > + const char *keymod, void *input, void *output, > + size_t length); > + > +/** 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 > + */ > +static inline int caam_encap_blob(struct caam_blob_priv *priv, > + const char *keymod, > + void *input, void *output, size_t > +length) { > + return caam_process_blob(priv, true, keymod, input, output, > +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 > + */ > +static inline int caam_decap_blob(struct caam_blob_priv *priv, > + const char *keymod, > + void *input, void *output, size_t > +length) { > + return caam_process_blob(priv, false, keymod, input, output, > +length); } > + > +#endif > -- > 2.30.2