[PATCH v2 1/2] security/keys/secure_key: Adds the secure key support based on CAAM.
Maik Otto
m.otto at phytec.de
Fri Jan 17 11:52:27 UTC 2020
Hi
I tested both patches in combination with
[RFC,2/2] dm-crypt: Use any key type which is registered from
https://patchwork.kernel.org/patch/10835633/ with bug fix
and an i.MX6Quad (logged device) with Mainline Kernel 4.19.88
The following tests were successful:
- key generation with CAAM
keyctl add secure kmk-master "new 64" @s
- export and import key blob with same controller
keyctl pipe 332995568 > secure_key.blob
reboot device
keyctl add secure kmk-master "load `cat secure_key.blob`" @s
- import keyblob with an other cpu and same keys for secure boot
caam_jr 2102000.jr1: caam op done err: 20000c1a
[ 185.788931] secure_key: key_blob decap fail (-22)
add_key: Invalid argument
=> failing import was expected: pass
- use key from keyring in dmcrypt with an sd-card
dmsetup create test --table "0 106496 crypt aes-xts-plain64
:64:secure:kmk-master 0 /dev/mmcblk0p3 0"
write,read reboot and read again
Tested-by: Maik Otto<m.otto at phytec.de>
Am 23.07.2018 um 13:14 schrieb Udit Agarwal:
> Secure keys are derieved using CAAM crypto block.
>
> Secure keys derieved are the random number symmetric keys from CAAM.
> Blobs corresponding to the key are formed using CAAM. User space
> will only be able to view the blob of the key.
>
> Signed-off-by: Udit Agarwal <udit.agarwal at nxp.com>
> Reviewed-by: Sahil Malhotra <sahil.malhotra at nxp.com>
> ---
> Changes in v2:
> Changes security/keys/Makefile to compile securekey module
> when CONFIG_SECURE_KEY is enabled as module.
>
> Documentation/security/keys/secure-key.rst | 67 +++
> MAINTAINERS | 11 +
> include/keys/secure-type.h | 33 ++
> security/keys/Kconfig | 11 +
> security/keys/Makefile | 5 +
> security/keys/secure_key.c | 339 ++++++++++++
> security/keys/securekey_desc.c | 608 +++++++++++++++++++++
> security/keys/securekey_desc.h | 141 +++++
> 8 files changed, 1215 insertions(+)
> create mode 100644 Documentation/security/keys/secure-key.rst
> create mode 100644 include/keys/secure-type.h
> create mode 100644 security/keys/secure_key.c
> create mode 100644 security/keys/securekey_desc.c
> create mode 100644 security/keys/securekey_desc.h
>
> diff --git a/Documentation/security/keys/secure-key.rst b/Documentation/security/keys/secure-key.rst
> new file mode 100644
> index 000000000000..a33ffd09d7bd
> --- /dev/null
> +++ b/Documentation/security/keys/secure-key.rst
> @@ -0,0 +1,67 @@
> +==========
> +Secure Key
> +==========
> +
> +Secure key is the new type added to kernel key ring service.
> +Secure key is a symmetric type key of minimum length 32 bytes
> +and with maximum possible length to be 128 bytes. It is produced
> +in kernel using the CAAM crypto engine. Userspace can only see
> +the blob for the corresponding key. All the blobs are displayed
> +or loaded in hex ascii.
> +
> +Secure key can be created on platforms which supports CAAM
> +hardware block. Secure key can also be used as a master key to
> +create the encrypted keys along with the existing key types in
> +kernel.
> +
> +Secure key uses CAAM hardware to generate the key and blobify its
> +content for userspace. Generated blobs are tied up with the hardware
> +secret key stored in CAAM, hence the same blob will not be able to
> +de-blobify with the different secret key on another machine.
> +
> +Usage::
> +
> + keyctl add secure <name> "new <keylen>" <ring>
> + keyctl load secure <name> "load <hex_blob>" <ring>
> + keyctl print <key_id>
> +
> +"keyctl add secure" option will create the random data of the
> +specified key len using CAAM and store it as a key in kernel.
> +Key contents will be displayed as blobs to the user in hex ascii.
> +User can input key len from 32 bytes to 128 bytes.
> +
> +"keyctl load secure" option will load the blob contents. In kernel,
> +key will be deirved using input blob and CAAM, along with the secret
> +key stored in CAAM.
> +
> +"keyctl print" will return the hex string of the blob corresponding to
> +key_id. Returned blob will be of key_len + 48 bytes. Extra 48 bytes are
> +the header bytes added by the CAAM.
> +
> +Example of secure key usage::
> +
> +1. Create the secure key with name kmk-master of length 32 bytes::
> +
> + $ keyctl add secure kmk-master "new 32" @u
> + 46001928
> +
> + $keyctl show
> + Session Keyring
> + 1030783626 --alswrv 0 65534 keyring: _uid_ses.0
> + 695927745 --alswrv 0 65534 \_ keyring: _uid.0
> + 46001928 --als-rv 0 0 \_ secure: kmk-master
> +
> +2. Print the blob contents for the kmk-master key::
> +
> + $ keyctl print 46001928
> + d9743445b640f3d59c1670dddc0bc9c2
> + 34fc9aab7dd05c965e6120025012f029b
> + 07faa4776c4f6ed02899e35a135531e9a
> + 6e5c2b51132f9d5aef28f68738e658296
> + 3fe583177cfe50d2542b659a13039
> +
> + $ keyctl pipe 46001928 > secure_key.blob
> +
> +3. Load the blob in the user key ring::
> +
> + $ keyctl load secure kmk-master "load 'cat secure_key.blob'" @u
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 9fd5e8808208..654be2ee4b0a 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -7939,6 +7939,17 @@ F: include/keys/trusted-type.h
> F: security/keys/trusted.c
> F: security/keys/trusted.h
>
> +KEYS-SECURE
> +M: Udit Agarwal <udit.agarwal at nxp.com>
> +R: Sahil Malhotra <sahil.malhotra at nxp.com>
> +L: linux-security-module at vger.kernel.org
> +L: keyrings at vger.kernel.org
> +S: Supported
> +F: include/keys/secure-type.h
> +F: security/keys/secure_key.c
> +F: security/keys/securekey_desc.c
> +F: security/keys/securekey_desc.h
> +
> KEYS/KEYRINGS:
> M: David Howells <dhowells at redhat.com>
> L: keyrings at vger.kernel.org
> diff --git a/include/keys/secure-type.h b/include/keys/secure-type.h
> new file mode 100644
> index 000000000000..5b7a5f144e41
> --- /dev/null
> +++ b/include/keys/secure-type.h
> @@ -0,0 +1,33 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2018 NXP.
> + *
> + */
> +
> +#ifndef _KEYS_SECURE_TYPE_H
> +#define _KEYS_SECURE_TYPE_H
> +
> +#include <linux/key.h>
> +#include <linux/rcupdate.h>
> +
> +/* Minimum key size to be used is 32 bytes and maximum key size fixed
> + * is 128 bytes.
> + * Blob size to be kept is Maximum key size + blob header added by CAAM.
> + */
> +
> +#define MIN_KEY_SIZE 32
> +#define MAX_KEY_SIZE 128
> +#define BLOB_HEADER_SIZE 48
> +
> +#define MAX_BLOB_SIZE (MAX_KEY_SIZE + BLOB_HEADER_SIZE)
> +
> +struct secure_key_payload {
> + struct rcu_head rcu;
> + unsigned int key_len;
> + unsigned int blob_len;
> + unsigned char key[MAX_KEY_SIZE + 1];
> + unsigned char blob[MAX_BLOB_SIZE];
> +};
> +
> +extern struct key_type key_type_secure;
> +#endif
> diff --git a/security/keys/Kconfig b/security/keys/Kconfig
> index 6462e6654ccf..7eb138b5a54f 100644
> --- a/security/keys/Kconfig
> +++ b/security/keys/Kconfig
> @@ -71,6 +71,17 @@ config TRUSTED_KEYS
>
> If you are unsure as to whether this is required, answer N.
>
> +config SECURE_KEYS
> + tristate "SECURE_KEYS"
> + depends on KEYS && CRYPTO_DEV_FSL_CAAM && CRYPTO_DEV_FSL_CAAM_JR
> + help
> + This option provide support for creating secure-type key and blobs
> + in kernel. Secure keys are random number symmetric keys generated
> + from CAAM. The CAAM creates the blobs for the random key.
> + Userspace will only be able to see the blob.
> +
> + If you are unsure as to whether this is required, answer N.
> +
> config ENCRYPTED_KEYS
> tristate "ENCRYPTED KEYS"
> depends on KEYS
> diff --git a/security/keys/Makefile b/security/keys/Makefile
> index ef1581b337a3..eec1c350e922 100644
> --- a/security/keys/Makefile
> +++ b/security/keys/Makefile
> @@ -28,4 +28,9 @@ obj-$(CONFIG_KEY_DH_OPERATIONS) += dh.o
> #
> obj-$(CONFIG_BIG_KEYS) += big_key.o
> obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
> +CFLAGS_secure_key.o += -I$(obj)/../../drivers/crypto/caam/
> +CFLAGS_securekey_desc.o += -I$(obj)/../../drivers/crypto/caam/
> +obj-$(CONFIG_SECURE_KEYS) += securekey.o
> +securekey-y := securekey_desc.o \
> + secure_key.o
> obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted-keys/
> diff --git a/security/keys/secure_key.c b/security/keys/secure_key.c
> new file mode 100644
> index 000000000000..ec8ad4394549
> --- /dev/null
> +++ b/security/keys/secure_key.c
> @@ -0,0 +1,339 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (C) 2018 NXP
> + * Secure key is generated using NXP CAAM hardware block. CAAM generates the
> + * random number (used as a key) and creates its blob for the user.
> + */
> +
> +#include <linux/slab.h>
> +#include <linux/parser.h>
> +#include <linux/string.h>
> +#include <linux/key-type.h>
> +#include <linux/rcupdate.h>
> +#include <keys/secure-type.h>
> +#include <linux/completion.h>
> +
> +#include "securekey_desc.h"
> +
> +static const char hmac_alg[] = "hmac(sha1)";
> +static const char hash_alg[] = "sha1";
> +
> +static struct crypto_shash *hashalg;
> +static struct crypto_shash *hmacalg;
> +
> +enum {
> + error = -1,
> + new_key,
> + load_blob,
> +};
> +
> +static const match_table_t key_tokens = {
> + {new_key, "new"},
> + {load_blob, "load"},
> + {error, NULL}
> +};
> +
> +static struct secure_key_payload *secure_payload_alloc(struct key *key)
> +{
> + struct secure_key_payload *sec_key = NULL;
> + int ret = 0;
> +
> + ret = key_payload_reserve(key, sizeof(*sec_key));
> + if (ret < 0)
> + goto out;
> +
> + sec_key = kzalloc(sizeof(*sec_key), GFP_KERNEL);
> + if (!sec_key)
> + goto out;
> +
> +out:
> + return sec_key;
> +}
> +
> +/*
> + * parse_inputdata - parse the keyctl input data and fill in the
> + * payload structure for key or its blob.
> + * param[in]: data pointer to the data to be parsed for creating key.
> + * param[in]: p pointer to secure key payload structure to fill parsed data
> + * On success returns 0, otherwise -EINVAL.
> + */
> +static int parse_inputdata(char *data, struct secure_key_payload *p)
> +{
> + substring_t args[MAX_OPT_ARGS];
> + long keylen = 0;
> + int ret = -EINVAL;
> + int key_cmd = -EINVAL;
> + char *c = NULL;
> +
> + c = strsep(&data, " \t");
> + if (!c) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + /* Get the keyctl command i.e. new_key or load_blob etc */
> + key_cmd = match_token(c, key_tokens, args);
> +
> + switch (key_cmd) {
> + case new_key:
> + /* first argument is key size */
> + c = strsep(&data, " \t");
> + if (!c) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + ret = kstrtol(c, 10, &keylen);
> + if (ret < 0 || keylen < MIN_KEY_SIZE ||
> + keylen > MAX_KEY_SIZE) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + p->key_len = keylen;
> + ret = new_key;
> +
> + break;
> + case load_blob:
> + /* first argument is blob data for CAAM*/
> + c = strsep(&data, " \t");
> + if (!c) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + /* Blob_len = No of characters in blob/2 */
> + p->blob_len = strlen(c) / 2;
> + if (p->blob_len > MAX_BLOB_SIZE) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + ret = hex2bin(p->blob, c, p->blob_len);
> + if (ret < 0) {
> + ret = -EINVAL;
> + goto out;
> + }
> + ret = load_blob;
> +
> + break;
> + case error:
> + ret = -EINVAL;
> + break;
> + }
> +
> +out:
> + return ret;
> +}
> +
> +/*
> + * secure_instantiate - create a new secure type key.
> + * Supports the operation to generate a new key. A random number
> + * is generated from CAAM as key data and the corresponding red blob
> + * is formed and stored as key_blob.
> + * Also supports the operation to load the blob and key is derived using
> + * that blob from CAAM.
> + * On success, return 0. Otherwise return errno.
> + */
> +static int secure_instantiate(struct key *key,
> + struct key_preparsed_payload *prep)
> +{
> + struct secure_key_payload *payload = NULL;
> + size_t datalen = prep->datalen;
> + char *data = NULL;
> + int key_cmd = 0;
> + int ret = 0;
> + enum sk_req_type sk_op_type;
> + struct device *dev = NULL;
> +
> + if (datalen <= 0 || datalen > 32767 || !prep->data) {
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + data = kmalloc(datalen + 1, GFP_KERNEL);
> + if (!data) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + memcpy(data, prep->data, datalen);
> + data[datalen] = '\0';
> +
> + payload = secure_payload_alloc(key);
> + if (!payload) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + /* Allocate caam job ring for operation to be performed from CAAM */
> + dev = caam_jr_alloc();
> + if (!dev) {
> + pr_info("caam_jr_alloc failed\n");
> + ret = -ENODEV;
> + goto out;
> + }
> +
> + key_cmd = parse_inputdata(data, payload);
> + if (key_cmd < 0) {
> + ret = key_cmd;
> + goto out;
> + }
> +
> + switch (key_cmd) {
> + case load_blob:
> + /*
> + * Red blob decryption to be done for load operation
> + * to derive the key.
> + */
> + sk_op_type = sk_red_blob_dec;
> + ret = key_deblob(payload, sk_op_type, dev);
> + if (ret != 0) {
> + pr_info("secure_key: key_blob decap fail (%d)\n", ret);
> + goto out;
> + }
> + break;
> + case new_key:
> + /* Get Random number from caam of the specified length */
> + sk_op_type = sk_get_random;
> + ret = caam_get_random(payload, sk_op_type, dev);
> + if (ret != 0) {
> + pr_info("secure_key: get_random fail (%d)\n", ret);
> + goto out;
> + }
> +
> + /* Generate red blob of key random bytes with CAAM */
> + sk_op_type = sk_red_blob_enc;
> + ret = key_blob(payload, sk_op_type, dev);
> + if (ret != 0) {
> + pr_info("secure_key: key_blob encap fail (%d)\n", ret);
> + goto out;
> + }
> + break;
> + default:
> + ret = -EINVAL;
> + goto out;
> + }
> +out:
> + if (data)
> + kzfree(data);
> + if (dev)
> + caam_jr_free(dev);
> +
> + if (!ret)
> + rcu_assign_keypointer(key, payload);
> + else
> + kzfree(payload);
> +
> + return ret;
> +}
> +
> +/*
> + * secure_read - copy the blob data to userspace in hex.
> + * param[in]: key pointer to key struct
> + * param[in]: buffer pointer to user data for creating key
> + * param[in]: buflen is the length of the buffer
> + * On success, return to userspace the secure key data size.
> + */
> +static long secure_read(const struct key *key, char __user *buffer,
> + size_t buflen)
> +{
> + const struct secure_key_payload *p = NULL;
> + char *ascii_buf;
> + char *bufp;
> + int i;
> +
> + p = dereference_key_locked(key);
> + if (!p)
> + return -EINVAL;
> +
> + if (buffer && buflen >= 2 * p->blob_len) {
> + ascii_buf = kmalloc(2 * p->blob_len, GFP_KERNEL);
> + if (!ascii_buf)
> + return -ENOMEM;
> +
> + bufp = ascii_buf;
> + for (i = 0; i < p->blob_len; i++)
> + bufp = hex_byte_pack(bufp, p->blob[i]);
> + if (copy_to_user(buffer, ascii_buf, 2 * p->blob_len) != 0) {
> + kzfree(ascii_buf);
> + return -EFAULT;
> + }
> + kzfree(ascii_buf);
> + }
> + return 2 * p->blob_len;
> +}
> +
> +/*
> + * secure_destroy - clear and free the key's payload
> + */
> +static void secure_destroy(struct key *key)
> +{
> + kzfree(key->payload.data[0]);
> +}
> +
> +struct key_type key_type_secure = {
> + .name = "secure",
> + .instantiate = secure_instantiate,
> + .destroy = secure_destroy,
> + .read = secure_read,
> +};
> +EXPORT_SYMBOL_GPL(key_type_secure);
> +
> +static void secure_shash_release(void)
> +{
> + if (hashalg)
> + crypto_free_shash(hashalg);
> + if (hmacalg)
> + crypto_free_shash(hmacalg);
> +}
> +
> +static int __init secure_shash_alloc(void)
> +{
> + int ret;
> +
> + hmacalg = crypto_alloc_shash(hmac_alg, 0, CRYPTO_ALG_ASYNC);
> + if (IS_ERR(hmacalg)) {
> + pr_info("secure_key: could not allocate crypto %s\n",
> + hmac_alg);
> + return PTR_ERR(hmacalg);
> + }
> +
> + hashalg = crypto_alloc_shash(hash_alg, 0, CRYPTO_ALG_ASYNC);
> + if (IS_ERR(hashalg)) {
> + pr_info("secure_key: could not allocate crypto %s\n",
> + hash_alg);
> + ret = PTR_ERR(hashalg);
> + goto hashalg_fail;
> + }
> +
> + return 0;
> +
> +hashalg_fail:
> + crypto_free_shash(hmacalg);
> + return ret;
> +}
> +
> +static int __init init_secure_key(void)
> +{
> + int ret;
> +
> + ret = secure_shash_alloc();
> + if (ret < 0)
> + return ret;
> +
> + ret = register_key_type(&key_type_secure);
> + if (ret < 0)
> + secure_shash_release();
> + return ret;
> +}
> +
> +static void __exit cleanup_secure_key(void)
> +{
> + secure_shash_release();
> + unregister_key_type(&key_type_secure);
> +}
> +
> +late_initcall(init_secure_key);
> +module_exit(cleanup_secure_key);
> +
> +MODULE_LICENSE("GPL");
> diff --git a/security/keys/securekey_desc.c b/security/keys/securekey_desc.c
> new file mode 100644
> index 000000000000..03a57cb93a74
> --- /dev/null
> +++ b/security/keys/securekey_desc.c
> @@ -0,0 +1,608 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2018 NXP
> + *
> + */
> +
> +#include <keys/secure-type.h>
> +#include "securekey_desc.h"
> +
> +/* key modifier for blob encapsulation & decapsulation descriptor */
> +u8 key_modifier[] = "SECURE_KEY";
> +u32 key_modifier_len = 10;
> +
> +void caam_sk_rng_desc(struct sk_req *skreq, struct sk_desc *skdesc)
> +{
> + struct sk_fetch_rnd_data *fetch_rnd_data = NULL;
> + struct random_desc *rnd_desc = NULL;
> + size_t len = 0;
> + u32 *desc = skreq->hwdesc;
> +
> + init_job_desc(desc, 0);
> +
> + fetch_rnd_data = &skreq->req_u.sk_fetch_rnd_data;
> + rnd_desc = &skdesc->dma_u.random_descp;
> + len = fetch_rnd_data->key_len;
> +
> + /* command 0x82500000 */
> + append_cmd(desc, CMD_OPERATION | OP_TYPE_CLASS1_ALG |
> + OP_ALG_ALGSEL_RNG);
> + /* command 0x60340000 | len */
> + append_cmd(desc, CMD_FIFO_STORE | FIFOST_TYPE_RNGSTORE | len);
> + append_ptr(desc, rnd_desc->rnd_data);
> +}
> +
> +void caam_sk_redblob_encap_desc(struct sk_req *skreq, struct sk_desc *skdesc)
> +{
> + struct redblob_encap_desc *red_blob_desc =
> + &skdesc->dma_u.redblob_encapdesc;
> + struct sk_red_blob_encap *red_blob_req =
> + &skreq->req_u.sk_red_blob_encap;
> + u32 *desc = skreq->hwdesc;
> +
> + init_job_desc(desc, 0);
> +
> + /* Load class 2 key with key modifier. */
> + append_key_as_imm(desc, key_modifier, key_modifier_len,
> + key_modifier_len, CLASS_2 | KEY_DEST_CLASS_REG);
> +
> + /* SEQ IN PTR Command. */
> + append_seq_in_ptr(desc, red_blob_desc->in_data, red_blob_req->data_sz,
> + 0);
> +
> + /* SEQ OUT PTR Command. */
> + append_seq_out_ptr(desc, red_blob_desc->redblob,
> + red_blob_req->redblob_sz, 0);
> +
> + /* RedBlob encapsulation PROTOCOL Command. */
> + append_operation(desc, OP_TYPE_ENCAP_PROTOCOL | OP_PCLID_BLOB);
> +}
> +
> +/* void caam_sk_redblob_decap_desc(struct sk_req *skreq, struct sk_desc *skdesc)
> + * brief CAAM Descriptor creator from redblob to plaindata.
> + * param[in] skreq Pointer to secure key request structure
> + * param[in] skdesc Pointer to secure key descriptor structure
> + */
> +void caam_sk_redblob_decap_desc(struct sk_req *skreq, struct sk_desc *skdesc)
> +{
> + struct redblob_decap_desc *red_blob_desc =
> + &skdesc->dma_u.redblob_decapdesc;
> + struct sk_red_blob_decap *red_blob_req =
> + &skreq->req_u.sk_red_blob_decap;
> + u32 *desc = skreq->hwdesc;
> +
> + init_job_desc(desc, 0);
> +
> + /* Load class 2 key with key modifier. */
> + append_key_as_imm(desc, key_modifier, key_modifier_len,
> + key_modifier_len, CLASS_2 | KEY_DEST_CLASS_REG);
> +
> + /* SEQ IN PTR Command. */
> + append_seq_in_ptr(desc, red_blob_desc->redblob,
> + red_blob_req->redblob_sz, 0);
> +
> + /* SEQ OUT PTR Command. */
> + append_seq_out_ptr(desc, red_blob_desc->out_data,
> + red_blob_req->data_sz, 0);
> +
> + /* RedBlob decapsulation PROTOCOL Command. */
> + append_operation(desc, OP_TYPE_DECAP_PROTOCOL | OP_PCLID_BLOB);
> +}
> +
> +/* int caam_sk_get_random_map(struct device *dev, struct sk_req *req,
> + * struct sk_desc *skdesc)
> + * brief DMA map the buffer virtual pointers to physical address.
> + * param[in] dev Pointer to job ring device structure
> + * param[in] req Pointer to secure key request structure
> + * param[in] skdesc Pointer to secure key descriptor structure
> + * return 0 on success, error value otherwise.
> + */
> +int caam_sk_get_random_map(struct device *dev, struct sk_req *req,
> + struct sk_desc *skdesc)
> +{
> + struct sk_fetch_rnd_data *fetch_rnd_data;
> + struct random_desc *rnd_desc;
> +
> + fetch_rnd_data = &req->req_u.sk_fetch_rnd_data;
> + rnd_desc = &skdesc->dma_u.random_descp;
> +
> + rnd_desc->rnd_data = dma_map_single(dev, fetch_rnd_data->data,
> + fetch_rnd_data->key_len, DMA_FROM_DEVICE);
> +
> + if (dma_mapping_error(dev, rnd_desc->rnd_data)) {
> + dev_err(dev, "Unable to map memory\n");
> + goto sk_random_map_fail;
> + }
> + return 0;
> +
> +sk_random_map_fail:
> + return -ENOMEM;
> +}
> +
> +/* int caam_sk_redblob_encap_map(struct device *dev, struct sk_req *req,
> + * struct sk_desc *skdesc)
> + * brief DMA map the buffer virtual pointers to physical address.
> + * param[in] dev Pointer to job ring device structure
> + * param[in] req Pointer to secure key request structure
> + * param[in] skdesc Pointer to secure key descriptor structure
> + * return 0 on success, error value otherwise.
> + */
> +int caam_sk_redblob_encap_map(struct device *dev, struct sk_req *req,
> + struct sk_desc *skdesc)
> +{
> + struct sk_red_blob_encap *red_blob_encap;
> + struct redblob_encap_desc *red_blob_desc;
> +
> + red_blob_encap = &req->req_u.sk_red_blob_encap;
> + red_blob_desc = &skdesc->dma_u.redblob_encapdesc;
> +
> + red_blob_desc->in_data = dma_map_single(dev, red_blob_encap->data,
> + red_blob_encap->data_sz, DMA_TO_DEVICE);
> + if (dma_mapping_error(dev, red_blob_desc->in_data)) {
> + dev_err(dev, "Unable to map memory\n");
> + goto sk_data_fail;
> + }
> +
> + red_blob_desc->redblob = dma_map_single(dev, red_blob_encap->redblob,
> + red_blob_encap->redblob_sz, DMA_FROM_DEVICE);
> + if (dma_mapping_error(dev, red_blob_desc->redblob)) {
> + dev_err(dev, "Unable to map memory\n");
> + goto sk_redblob_fail;
> + }
> +
> + return 0;
> +
> +sk_redblob_fail:
> + dma_unmap_single(dev, red_blob_desc->in_data, red_blob_encap->data_sz,
> + DMA_TO_DEVICE);
> +sk_data_fail:
> + return -ENOMEM;
> +}
> +
> +/* static int caam_sk_redblob_decap_map(struct device *dev,
> + * struct sk_req *req,
> + * struct sk_desc *skdesc)
> + * brief DMA map the buffer virtual pointers to physical address.
> + * param[in] dev Pointer to job ring device structure
> + * param[in] req Pointer to secure key request structure
> + * param[in] skdesc Pointer to secure key descriptor structure
> + * return 0 on success, error value otherwise.
> + */
> +int caam_sk_redblob_decap_map(struct device *dev, struct sk_req *req,
> + struct sk_desc *skdesc)
> +{
> + struct sk_red_blob_decap *red_blob_decap;
> + struct redblob_decap_desc *red_blob_desc;
> +
> + red_blob_decap = &req->req_u.sk_red_blob_decap;
> + red_blob_desc = &skdesc->dma_u.redblob_decapdesc;
> +
> + red_blob_desc->redblob = dma_map_single(dev, red_blob_decap->redblob,
> + red_blob_decap->redblob_sz, DMA_TO_DEVICE);
> + if (dma_mapping_error(dev, red_blob_desc->redblob)) {
> + dev_err(dev, "Unable to map memory\n");
> + goto sk_redblob_fail;
> + }
> +
> + red_blob_desc->out_data = dma_map_single(dev, red_blob_decap->data,
> + red_blob_decap->data_sz, DMA_FROM_DEVICE);
> + if (dma_mapping_error(dev, red_blob_desc->out_data)) {
> + dev_err(dev, "Unable to map memory\n");
> + goto sk_data_fail;
> + }
> +
> + return 0;
> +
> +sk_data_fail:
> + dma_unmap_single(dev, red_blob_desc->redblob,
> + red_blob_decap->redblob_sz, DMA_TO_DEVICE);
> +sk_redblob_fail:
> + return -ENOMEM;
> +}
> +
> +/* @fn void securekey_unmap(struct device *dev,
> + * struct sk_desc *skdesc, struct sk_req *req)
> + * @brief DMA unmap the buffer pointers.
> + * @param[in] dev Pointer to job ring device structure
> + * @param[in] skdesc Pointer to secure key descriptor structure
> + * @param[in] req Pointer to secure key request structure
> + */
> +void securekey_unmap(struct device *dev,
> + struct sk_desc *skdesc, struct sk_req *req)
> +{
> +
> + switch (req->type) {
> + case sk_get_random:
> + {
> + struct sk_fetch_rnd_data *fetch_rnd_data;
> + struct random_desc *rnd_desc;
> +
> + fetch_rnd_data = &req->req_u.sk_fetch_rnd_data;
> + rnd_desc = &skdesc->dma_u.random_descp;
> +
> + /* Unmap Descriptor buffer pointers. */
> + dma_unmap_single(dev, rnd_desc->rnd_data,
> + fetch_rnd_data->key_len,
> + DMA_FROM_DEVICE);
> + break;
> + }
> + case sk_red_blob_enc:
> + {
> + struct sk_red_blob_encap *red_blob_encap;
> + struct redblob_encap_desc *red_blob_desc;
> +
> + red_blob_encap = &req->req_u.sk_red_blob_encap;
> + red_blob_desc = &skdesc->dma_u.redblob_encapdesc;
> +
> + /* Unmap Descriptor buffer pointers. */
> + dma_unmap_single(dev, red_blob_desc->in_data,
> + red_blob_encap->data_sz,
> + DMA_TO_DEVICE);
> +
> + dma_unmap_single(dev, red_blob_desc->redblob,
> + red_blob_encap->redblob_sz,
> + DMA_FROM_DEVICE);
> +
> + break;
> + }
> + case sk_red_blob_dec:
> + {
> + struct sk_red_blob_decap *red_blob_decap;
> + struct redblob_decap_desc *red_blob_desc;
> +
> + red_blob_decap = &req->req_u.sk_red_blob_decap;
> + red_blob_desc = &skdesc->dma_u.redblob_decapdesc;
> +
> + /* Unmap Descriptor buffer pointers. */
> + dma_unmap_single(dev, red_blob_desc->redblob,
> + red_blob_decap->redblob_sz,
> + DMA_TO_DEVICE);
> +
> + dma_unmap_single(dev, red_blob_desc->out_data,
> + red_blob_decap->data_sz,
> + DMA_FROM_DEVICE);
> +
> + break;
> + }
> + default:
> + dev_err(dev, "Unable to find request type\n");
> + break;
> + }
> + kfree(skdesc);
> +}
> +
> +/* int caam_securekey_desc_init(struct device *dev, struct sk_req *req)
> + * brief CAAM Descriptor creator for secure key operations.
> + * param[in] dev Pointer to job ring device structure
> + * param[in] req Pointer to secure key request structure
> + * return 0 on success, error value otherwise.
> + */
> +int caam_securekey_desc_init(struct device *dev, struct sk_req *req)
> +{
> + struct sk_desc *skdesc = NULL;
> + int ret = 0;
> +
> + switch (req->type) {
> + case sk_get_random:
> + {
> + skdesc = kmalloc(sizeof(*skdesc), GFP_DMA);
> + if (!skdesc) {
> + ret = -ENOMEM;
> + goto out;
> + }
> + skdesc->req_type = req->type;
> +
> + if (caam_sk_get_random_map(dev, req, skdesc)) {
> + dev_err(dev, "caam get_random map fail\n");
> + ret = -ENOMEM;
> + goto out;
> + }
> + caam_sk_rng_desc(req, skdesc);
> + break;
> + }
> + case sk_red_blob_enc:
> + {
> + skdesc = kmalloc(sizeof(*skdesc), GFP_DMA);
> + if (!skdesc) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + skdesc->req_type = req->type;
> +
> + if (caam_sk_redblob_encap_map(dev, req, skdesc)) {
> + dev_err(dev, "caam redblob_encap map fail\n");
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + /* Descriptor function to create redblob from data. */
> + caam_sk_redblob_encap_desc(req, skdesc);
> + break;
> + }
> +
> + case sk_red_blob_dec:
> + {
> + skdesc = kmalloc(sizeof(*skdesc), GFP_DMA);
> + if (!skdesc) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + skdesc->req_type = req->type;
> +
> + if (caam_sk_redblob_decap_map(dev, req, skdesc)) {
> + dev_err(dev, "caam redblob_decap map fail\n");
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + /* Descriptor function to decap data from redblob. */
> + caam_sk_redblob_decap_desc(req, skdesc);
> + break;
> + }
> + default:
> + pr_debug("Unknown request type\n");
> + ret = -EINVAL;
> + goto out;
> + }
> +
> + req->desc_pointer = (void *)skdesc;
> +
> +out:
> + return ret;
> +}
> +
> +/* static void caam_op_done (struct device *dev, u32 *desc, u32 ret,
> + * void *context)
> + * brief callback function to be called when descriptor executed.
> + * param[in] dev Pointer to device structure
> + * param[in] desc descriptor pointer
> + * param[in] ret return status of Job submitted
> + * param[in] context void pointer
> + */
> +static void caam_op_done(struct device *dev, u32 *desc, u32 ret,
> + void *context)
> +{
> + struct sk_req *req = context;
> +
> + if (ret) {
> + dev_err(dev, "caam op done err: %x\n", ret);
> + /* print the error source name. */
> + caam_jr_strstatus(dev, ret);
> + }
> + /* Call securekey_unmap function for unmapping the buffer pointers. */
> + securekey_unmap(dev, req->desc_pointer, req);
> +
> + req->ret = ret;
> + complete(&req->comp);
> +}
> +
> +
> +/* static int sk_job_submit(struct device *jrdev, struct sk_req *req)
> + * brief Enqueue a Job descriptor to Job ring and wait until SEC returns.
> + * param[in] jrdev Pointer to job ring device structure
> + * param[in] req Pointer to secure key request structure
> + * return 0 on success, error value otherwise.
> + */
> +static int sk_job_submit(struct device *jrdev, struct sk_req *req)
> +{
> + int ret;
> +
> + init_completion(&req->comp);
> +
> + /* caam_jr_enqueue function for Enqueue a job descriptor */
> + ret = caam_jr_enqueue(jrdev, req->hwdesc, caam_op_done, req);
> + if (!ret)
> + wait_for_completion_interruptible(&req->comp);
> +
> + ret = req->ret;
> + return ret;
> +}
> +
> +/* caam_get_random(struct secure_key_payload *p, enum sk_req_type fetch_rnd,
> + * struct device *dev)
> + * Create the random number of the specified length using CAAM block
> + * param[in]: out pointer to place the random bytes
> + * param[in]: length for the random data bytes.
> + * param[in]: dev Pointer to job ring device structure
> + * If operation is successful return 0, otherwise error.
> + */
> +int caam_get_random(struct secure_key_payload *p, enum sk_req_type fetch_rnd,
> + struct device *dev)
> +{
> + struct sk_fetch_rnd_data *fetch_rnd_data = NULL;
> + struct sk_req *req = NULL;
> + int ret = 0;
> + void *temp = NULL;
> +
> + req = kmalloc(sizeof(struct sk_req), GFP_DMA);
> + if (!req) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + req->type = fetch_rnd;
> + fetch_rnd_data = &(req->req_u.sk_fetch_rnd_data);
> +
> + /* initialise with key length */
> + fetch_rnd_data->key_len = p->key_len;
> +
> + temp = kmalloc(fetch_rnd_data->key_len, GFP_DMA);
> + if (!temp) {
> + ret = -ENOMEM;
> + goto out;
> + }
> + fetch_rnd_data->data = temp;
> +
> + ret = caam_securekey_desc_init(dev, req);
> +
> + if (ret) {
> + pr_info("caam_securekey_desc_init failed\n");
> + goto out;
> + }
> +
> + ret = sk_job_submit(dev, req);
> + if (!ret) {
> + /*Copy output to key buffer. */
> + memcpy(p->key, fetch_rnd_data->data, p->key_len);
> + } else {
> + ret = -EINVAL;
> + }
> +
> +out:
> + if (req)
> + kfree(req);
> +
> + if (temp)
> + kfree(temp);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL(caam_get_random);
> +
> +/* key_deblob(struct secure_key_payload *p, enum sk_req_type decap_type
> + * struct device *dev)
> + * Deblobify the blob to get the key data and fill in secure key payload struct
> + * param[in] p pointer to the secure key payload
> + * param[in] decap_type operation to be done.
> + * param[in] dev dev Pointer to job ring device structure
> + * If operation is successful return 0, otherwise error.
> + */
> +int key_deblob(struct secure_key_payload *p, enum sk_req_type decap_type,
> + struct device *dev)
> +{
> + unsigned int blob_len;
> + struct sk_red_blob_decap *d_blob;
> + struct sk_req *req = NULL;
> + int total_sz = 0, *temp = NULL, ret = 0;
> +
> + req = kmalloc(sizeof(struct sk_req), GFP_DMA);
> + if (!req) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + d_blob = &(req->req_u.sk_red_blob_decap);
> + blob_len = p->blob_len;
> + req->type = decap_type;
> +
> + /*
> + * Red blob size is the blob_len filled in payload struct
> + * Data_sz i.e. key is the blob_len - blob header size
> + */
> +
> + d_blob->redblob_sz = blob_len;
> + d_blob->data_sz = blob_len - (SK_BLOB_KEY_SZ + SK_BLOB_MAC_SZ);
> + total_sz = d_blob->data_sz + d_blob->redblob_sz;
> +
> + temp = kmalloc(total_sz, GFP_DMA);
> + if (!temp) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + req->mem_pointer = temp;
> + d_blob->redblob = temp;
> + d_blob->data = d_blob->redblob + d_blob->redblob_sz;
> + memcpy(d_blob->redblob, p->blob, blob_len);
> +
> + ret = caam_securekey_desc_init(dev, req);
> +
> + if (ret) {
> + pr_info("caam_securekey_desc_init: Failed\n");
> + goto out;
> + }
> +
> + ret = sk_job_submit(dev, req);
> + if (!ret) {
> + /*Copy output to key buffer. */
> + p->key_len = d_blob->data_sz;
> + memcpy(p->key, d_blob->data, p->key_len);
> + } else {
> + ret = -EINVAL;
> + }
> +
> +out:
> + if (temp)
> + kfree(temp);
> + if (req)
> + kfree(req);
> + return ret;
> +}
> +EXPORT_SYMBOL(key_deblob);
> +
> +/* key_blob(struct secure_key_payload *p, enum sk_req_type encap_type,
> + * struct device *dev)
> + * To blobify the key data to get the blob. This blob can only be seen by
> + * userspace.
> + * param[in] p pointer to the secure key payload
> + * param[in] decap_type operation to be done.
> + * param[in] dev dev Pointer to job ring device structure
> + * If operation is successful return 0, otherwise error.
> + */
> +int key_blob(struct secure_key_payload *p, enum sk_req_type encap_type,
> + struct device *dev)
> +{
> + unsigned int key_len;
> + struct sk_red_blob_encap *k_blob;
> + struct sk_req *req = NULL;
> + int total_sz = 0, *temp = NULL, ret = 0;
> +
> + req = kmalloc(sizeof(struct sk_req), GFP_DMA);
> + if (!req) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + key_len = p->key_len;
> +
> + req->type = encap_type;
> + k_blob = &(req->req_u.sk_red_blob_encap);
> +
> + /*
> + * Data_sz i.e. key len and the corresponding blob_len is
> + * key_len + BLOB header size.
> + */
> +
> + k_blob->data_sz = key_len;
> + k_blob->redblob_sz = key_len + SK_BLOB_KEY_SZ + SK_BLOB_MAC_SZ;
> + total_sz = k_blob->data_sz + k_blob->redblob_sz;
> +
> + temp = kmalloc(total_sz, GFP_DMA);
> + if (!temp) {
> + ret = -ENOMEM;
> + goto out;
> + }
> +
> + req->mem_pointer = temp;
> + k_blob->data = temp;
> +
> + k_blob->redblob = k_blob->data + k_blob->data_sz;
> + memcpy(k_blob->data, p->key, key_len);
> +
> + ret = caam_securekey_desc_init(dev, req);
> +
> + if (ret) {
> + pr_info("caam_securekey_desc_init failed\n");
> + goto out;
> + }
> +
> + ret = sk_job_submit(dev, req);
> + if (!ret) {
> + /*Copy output to key buffer. */
> + p->blob_len = k_blob->redblob_sz;
> + memcpy(p->blob, k_blob->redblob, p->blob_len);
> + } else {
> + ret = -EINVAL;
> + }
> +
> +out:
> + if (temp)
> + kfree(req->mem_pointer);
> + if (req)
> + kfree(req);
> + return ret;
> +
> +}
> +EXPORT_SYMBOL(key_blob);
> diff --git a/security/keys/securekey_desc.h b/security/keys/securekey_desc.h
> new file mode 100644
> index 000000000000..0ee26e95b205
> --- /dev/null
> +++ b/security/keys/securekey_desc.h
> @@ -0,0 +1,141 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright 2018 NXP
> + *
> + */
> +#ifndef _SECUREKEY_DESC_H_
> +#define _SECUREKEY_DESC_H_
> +
> +#include "compat.h"
> +#include "regs.h"
> +#include "intern.h"
> +#include "desc.h"
> +#include "desc_constr.h"
> +#include "jr.h"
> +#include "error.h"
> +#include "pdb.h"
> +
> +#define SK_BLOB_KEY_SZ 32 /* Blob key size. */
> +#define SK_BLOB_MAC_SZ 16 /* Blob MAC size. */
> +
> +/*
> + * brief defines different kinds of operations supported by this module.
> + */
> +enum sk_req_type {
> + sk_get_random,
> + sk_red_blob_enc,
> + sk_red_blob_dec,
> +};
> +
> +
> +/*
> + * struct random_des
> + * param[out] rnd_data output buffer for random data.
> + */
> +struct random_desc {
> + dma_addr_t rnd_data;
> +};
> +
> +/* struct redblob_encap_desc
> + * details Structure containing dma address for redblob encapsulation.
> + * param[in] in_data input data to redblob encap descriptor.
> + * param[out] redblob output buffer for redblob.
> + */
> +struct redblob_encap_desc {
> + dma_addr_t in_data;
> + dma_addr_t redblob;
> +};
> +
> +/* struct redblob_decap_desc
> + * details Structure containing dma address for redblob decapsulation.
> + * param[in] redblob input buffer to redblob decap descriptor.
> + * param[out] out_data output data from redblob decap descriptor.
> + */
> +struct redblob_decap_desc {
> + dma_addr_t redblob;
> + dma_addr_t out_data;
> +};
> +
> +/* struct sk_desc
> + * details Structure for securekey descriptor creation.
> + * param[in] req_type operation supported.
> + * param[in] dma_u union of struct for supported operation.
> + */
> +struct sk_desc {
> + u32 req_type;
> + union {
> + struct redblob_encap_desc redblob_encapdesc;
> + struct redblob_decap_desc redblob_decapdesc;
> + struct random_desc random_descp;
> + } dma_u;
> +};
> +
> +/* struct sk_fetch_rnd_data
> + * decriptor structure containing key length.
> + */
> +struct sk_fetch_rnd_data {
> + void *data;
> + size_t key_len;
> +};
> +
> +/* struct sk_red_blob_encap
> + * details Structure containing buffer pointers for redblob encapsulation.
> + * param[in] data Input data.
> + * param[in] data_sz size of Input data.
> + * param[out] redblob output buffer for redblob.
> + * param[in] redblob_sz size of redblob.
> + */
> +struct sk_red_blob_encap {
> + void *data;
> + uint32_t data_sz;
> + void *redblob;
> + uint32_t redblob_sz;
> +};
> +
> +/* struct sk_red_blob_decap
> + * details Structure containing buffer pointers for redblob decapsulation.
> + * param[in] redblob Input redblob.
> + * param[in] redblob_sz size of redblob.
> + * param[out] data output buffer for data.
> + * param[in] data_sz size of output data.
> + */
> +struct sk_red_blob_decap {
> + void *redblob;
> + uint32_t redblob_sz;
> + void *data;
> + uint32_t data_sz;
> +};
> +
> +/* struct sk_req
> + * details Structure for securekey request creation.
> + * param[in] type operation supported.
> + * param[in] req_u union of struct for supported operation.
> + * param[out] ret return status of CAAM operation.
> + * param[in] mem_pointer memory pointer for allocated kernel memory.
> + * param[in] desc_pointer Pointer to securekey descriptor creation structure.
> + * param[in] comp struct completion object.
> + * param[in] hwdesc contains descriptor instructions.
> + */
> +struct sk_req {
> + enum sk_req_type type;
> + void *arg;
> + union {
> + struct sk_red_blob_encap sk_red_blob_encap;
> + struct sk_red_blob_decap sk_red_blob_decap;
> + struct sk_fetch_rnd_data sk_fetch_rnd_data;
> + } req_u;
> + int ret;
> + void *mem_pointer;
> + void *desc_pointer;
> + struct completion comp;
> + u32 hwdesc[MAX_CAAM_DESCSIZE];
> +};
> +
> +int caam_get_random(struct secure_key_payload *p, enum sk_req_type fetch_rnd,
> + struct device *dev);
> +int key_blob(struct secure_key_payload *p, enum sk_req_type encap_type,
> + struct device *dev);
> +int key_deblob(struct secure_key_payload *p, enum sk_req_type decap_type,
> + struct device *dev);
> +
> +#endif /*_SECUREKEY_DESC_H_*/
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