Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 621BFC433EF for ; Wed, 24 Nov 2021 07:48:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240693AbhKXHvk (ORCPT ); Wed, 24 Nov 2021 02:51:40 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44056 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240644AbhKXHvj (ORCPT ); Wed, 24 Nov 2021 02:51:39 -0500 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE24DC061574 for ; Tue, 23 Nov 2021 23:48:29 -0800 (PST) Received: from gallifrey.ext.pengutronix.de ([2001:67c:670:201:5054:ff:fe8d:eefb] helo=[127.0.0.1]) by metis.ext.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1mpn0y-0000Fa-Da; Wed, 24 Nov 2021 08:48:24 +0100 Subject: Re: [PATCH v4 4/5] crypto: caam - add in-kernel interface for blob generator From: Ahmad Fatoum To: =?UTF-8?Q?Horia_Geant=c4=83?= , Aymen Sghaier , Herbert Xu , "David S. Miller" Cc: linux-security-module@vger.kernel.org, Eric Biggers , David Gstir , Sumit Garg , Jan Luebbe , Richard Weinberger , James Bottomley , Franck LENORMAND , James Morris , Mimi Zohar , linux-kernel@vger.kernel.org, David Howells , Jarkko Sakkinen , keyrings@vger.kernel.org, linux-crypto@vger.kernel.org, kernel@pengutronix.de, Udit Agarwal , linux-integrity@vger.kernel.org, Tim Harvey , "Serge E. Hallyn" References: <3ea6e5c37559eddfdc51f26c4dff0abbbc894839.1633946449.git-series.a.fatoum@pengutronix.de> <41c73628-e687-c72d-9753-b778cb398ddc@pengutronix.de> Message-ID: <4df10810-dd74-93ad-5a42-89b7b6133567@pengutronix.de> Date: Wed, 24 Nov 2021 08:48:16 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.14.0 MIME-Version: 1.0 In-Reply-To: <41c73628-e687-c72d-9753-b778cb398ddc@pengutronix.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 2001:67c:670:201:5054:ff:fe8d:eefb X-SA-Exim-Mail-From: a.fatoum@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-crypto@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org Hello again, On 01.11.21 09:00, Ahmad Fatoum wrote: > Hello Horia, Aymen, > > On 11.10.21 12:02, 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. > > Did you have time to look at this again? Ping. > > I have incorporated the changes request in v1 and the > code has since been reviewed and tested by others. > > Thanks, > Ahmad > >> Reviewed-by: David Gstir >> Tested-By: Tim Harvey >> Signed-off-by: Steffen Trumtrar >> Signed-off-by: Ahmad Fatoum >> --- >> To: "Horia Geantă" >> To: Aymen Sghaier >> To: Herbert Xu >> To: "David S. Miller" >> Cc: James Bottomley >> Cc: Jarkko Sakkinen >> Cc: Mimi Zohar >> Cc: David Howells >> Cc: James Morris >> Cc: Eric Biggers >> Cc: "Serge E. Hallyn" >> Cc: Udit Agarwal >> Cc: Jan Luebbe >> Cc: David Gstir >> Cc: Richard Weinberger >> Cc: Franck LENORMAND >> Cc: Sumit Garg >> 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 >> + * Copyright (C) 2021 Pengutronix, Ahmad Fatoum >> + */ >> + >> +#include >> +#include >> + >> +#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..83fd990ebdce >> --- /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 >> + */ >> + >> +#ifndef __CAAM_BLOB_GEN >> +#define __CAAM_BLOB_GEN >> + >> +#include >> + >> +#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_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 |