BACKPORT: FROMLIST: scsi: ufs: UFS crypto API

Introduce functions to manipulate UFS inline encryption hardware
in line with the JEDEC UFSHCI v2.1 specification and to work with the
block keyslot manager.

Bug: 137270441
Test: tested as series; see I26aac0ac7845a9064f28bb1421eb2522828a6dec
Change-Id: I4c6ba30f30eaea83da6822381ae2aa85b40e7b90
Signed-off-by: Satya Tangirala <satyat@google.com>
Link: https://patchwork.kernel.org/patch/11214745/
This commit is contained in:
Satya Tangirala 2019-10-24 14:44:27 -07:00 committed by Alistair Delva
parent e00aafeeaa
commit eedb625131
5 changed files with 501 additions and 0 deletions

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@ -109,3 +109,12 @@ config SCSI_UFS_HISI
Select this if you have UFS controller on Hisilicon chipset.
If unsure, say N.
config SCSI_UFS_CRYPTO
bool "UFS Crypto Engine Support"
depends on SCSI_UFSHCD && BLK_INLINE_ENCRYPTION
help
Enable Crypto Engine Support in UFS.
Enabling this makes it possible for the kernel to use the crypto
capabilities of the UFS device (if present) to perform crypto
operations on data being transferred to/from the device.

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@ -8,3 +8,4 @@ ufshcd-core-objs := ufshcd.o ufs-sysfs.o
obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o
obj-$(CONFIG_SCSI_UFS_HISI) += ufs-hisi.o
ufshcd-core-$(CONFIG_SCSI_UFS_CRYPTO) += ufshcd-crypto.o

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@ -0,0 +1,391 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Copyright 2019 Google LLC
*/
#include <crypto/algapi.h>
#include "ufshcd.h"
#include "ufshcd-crypto.h"
static bool ufshcd_cap_idx_valid(struct ufs_hba *hba, unsigned int cap_idx)
{
return cap_idx < hba->crypto_capabilities.num_crypto_cap;
}
static u8 get_data_unit_size_mask(unsigned int data_unit_size)
{
if (data_unit_size < 512 || data_unit_size > 65536 ||
!is_power_of_2(data_unit_size))
return 0;
return data_unit_size / 512;
}
static size_t get_keysize_bytes(enum ufs_crypto_key_size size)
{
switch (size) {
case UFS_CRYPTO_KEY_SIZE_128: return 16;
case UFS_CRYPTO_KEY_SIZE_192: return 24;
case UFS_CRYPTO_KEY_SIZE_256: return 32;
case UFS_CRYPTO_KEY_SIZE_512: return 64;
default: return 0;
}
}
static int ufshcd_crypto_cap_find(void *hba_p,
enum blk_crypto_mode_num crypto_mode,
unsigned int data_unit_size)
{
struct ufs_hba *hba = hba_p;
enum ufs_crypto_alg ufs_alg;
u8 data_unit_mask;
int cap_idx;
enum ufs_crypto_key_size ufs_key_size;
union ufs_crypto_cap_entry *ccap_array = hba->crypto_cap_array;
if (!ufshcd_hba_is_crypto_supported(hba))
return -EINVAL;
switch (crypto_mode) {
case BLK_ENCRYPTION_MODE_AES_256_XTS:
ufs_alg = UFS_CRYPTO_ALG_AES_XTS;
ufs_key_size = UFS_CRYPTO_KEY_SIZE_256;
break;
default: return -EINVAL;
}
data_unit_mask = get_data_unit_size_mask(data_unit_size);
for (cap_idx = 0; cap_idx < hba->crypto_capabilities.num_crypto_cap;
cap_idx++) {
if (ccap_array[cap_idx].algorithm_id == ufs_alg &&
(ccap_array[cap_idx].sdus_mask & data_unit_mask) &&
ccap_array[cap_idx].key_size == ufs_key_size)
return cap_idx;
}
return -EINVAL;
}
/**
* ufshcd_crypto_cfg_entry_write_key - Write a key into a crypto_cfg_entry
*
* Writes the key with the appropriate format - for AES_XTS,
* the first half of the key is copied as is, the second half is
* copied with an offset halfway into the cfg->crypto_key array.
* For the other supported crypto algs, the key is just copied.
*
* @cfg: The crypto config to write to
* @key: The key to write
* @cap: The crypto capability (which specifies the crypto alg and key size)
*
* Returns 0 on success, or -EINVAL
*/
static int ufshcd_crypto_cfg_entry_write_key(union ufs_crypto_cfg_entry *cfg,
const u8 *key,
union ufs_crypto_cap_entry cap)
{
size_t key_size_bytes = get_keysize_bytes(cap.key_size);
if (key_size_bytes == 0)
return -EINVAL;
switch (cap.algorithm_id) {
case UFS_CRYPTO_ALG_AES_XTS:
key_size_bytes *= 2;
if (key_size_bytes > UFS_CRYPTO_KEY_MAX_SIZE)
return -EINVAL;
memcpy(cfg->crypto_key, key, key_size_bytes/2);
memcpy(cfg->crypto_key + UFS_CRYPTO_KEY_MAX_SIZE/2,
key + key_size_bytes/2, key_size_bytes/2);
return 0;
case UFS_CRYPTO_ALG_BITLOCKER_AES_CBC: // fallthrough
case UFS_CRYPTO_ALG_AES_ECB: // fallthrough
case UFS_CRYPTO_ALG_ESSIV_AES_CBC:
memcpy(cfg->crypto_key, key, key_size_bytes);
return 0;
}
return -EINVAL;
}
static void program_key(struct ufs_hba *hba,
const union ufs_crypto_cfg_entry *cfg,
int slot)
{
int i;
u32 slot_offset = hba->crypto_cfg_register + slot * sizeof(*cfg);
/* Clear the dword 16 */
ufshcd_writel(hba, 0, slot_offset + 16 * sizeof(cfg->reg_val[0]));
/* Ensure that CFGE is cleared before programming the key */
wmb();
for (i = 0; i < 16; i++) {
ufshcd_writel(hba, le32_to_cpu(cfg->reg_val[i]),
slot_offset + i * sizeof(cfg->reg_val[0]));
/* Spec says each dword in key must be written sequentially */
wmb();
}
/* Write dword 17 */
ufshcd_writel(hba, le32_to_cpu(cfg->reg_val[17]),
slot_offset + 17 * sizeof(cfg->reg_val[0]));
/* Dword 16 must be written last */
wmb();
/* Write dword 16 */
ufshcd_writel(hba, le32_to_cpu(cfg->reg_val[16]),
slot_offset + 16 * sizeof(cfg->reg_val[0]));
wmb();
}
static int ufshcd_crypto_keyslot_program(void *hba_p, const u8 *key,
enum blk_crypto_mode_num crypto_mode,
unsigned int data_unit_size,
unsigned int slot)
{
struct ufs_hba *hba = hba_p;
int err = 0;
u8 data_unit_mask;
union ufs_crypto_cfg_entry cfg;
union ufs_crypto_cfg_entry *cfg_arr = hba->crypto_cfgs;
int cap_idx;
cap_idx = ufshcd_crypto_cap_find(hba_p, crypto_mode,
data_unit_size);
if (!ufshcd_is_crypto_enabled(hba) ||
!ufshcd_keyslot_valid(hba, slot) ||
!ufshcd_cap_idx_valid(hba, cap_idx))
return -EINVAL;
data_unit_mask = get_data_unit_size_mask(data_unit_size);
if (!(data_unit_mask & hba->crypto_cap_array[cap_idx].sdus_mask))
return -EINVAL;
memset(&cfg, 0, sizeof(cfg));
cfg.data_unit_size = data_unit_mask;
cfg.crypto_cap_idx = cap_idx;
cfg.config_enable |= UFS_CRYPTO_CONFIGURATION_ENABLE;
err = ufshcd_crypto_cfg_entry_write_key(&cfg, key,
hba->crypto_cap_array[cap_idx]);
if (err)
return err;
program_key(hba, &cfg, slot);
memcpy(&cfg_arr[slot], &cfg, sizeof(cfg));
memzero_explicit(&cfg, sizeof(cfg));
return 0;
}
static int ufshcd_crypto_keyslot_find(void *hba_p,
const u8 *key,
enum blk_crypto_mode_num crypto_mode,
unsigned int data_unit_size)
{
struct ufs_hba *hba = hba_p;
int err = 0;
int slot;
u8 data_unit_mask;
union ufs_crypto_cfg_entry cfg;
union ufs_crypto_cfg_entry *cfg_arr = hba->crypto_cfgs;
int cap_idx;
cap_idx = ufshcd_crypto_cap_find(hba_p, crypto_mode,
data_unit_size);
if (!ufshcd_is_crypto_enabled(hba) ||
!ufshcd_cap_idx_valid(hba, cap_idx))
return -EINVAL;
data_unit_mask = get_data_unit_size_mask(data_unit_size);
if (!(data_unit_mask & hba->crypto_cap_array[cap_idx].sdus_mask))
return -EINVAL;
memset(&cfg, 0, sizeof(cfg));
err = ufshcd_crypto_cfg_entry_write_key(&cfg, key,
hba->crypto_cap_array[cap_idx]);
if (err)
return -EINVAL;
for (slot = 0; slot < NUM_KEYSLOTS(hba); slot++) {
if ((cfg_arr[slot].config_enable &
UFS_CRYPTO_CONFIGURATION_ENABLE) &&
data_unit_mask == cfg_arr[slot].data_unit_size &&
cap_idx == cfg_arr[slot].crypto_cap_idx &&
!crypto_memneq(&cfg.crypto_key, cfg_arr[slot].crypto_key,
UFS_CRYPTO_KEY_MAX_SIZE)) {
memzero_explicit(&cfg, sizeof(cfg));
return slot;
}
}
memzero_explicit(&cfg, sizeof(cfg));
return -ENOKEY;
}
static int ufshcd_crypto_keyslot_evict(void *hba_p, const u8 *key,
enum blk_crypto_mode_num crypto_mode,
unsigned int data_unit_size,
unsigned int slot)
{
struct ufs_hba *hba = hba_p;
int i = 0;
u32 reg_base;
union ufs_crypto_cfg_entry *cfg_arr = hba->crypto_cfgs;
if (!ufshcd_is_crypto_enabled(hba) ||
!ufshcd_keyslot_valid(hba, slot))
return -EINVAL;
memset(&cfg_arr[slot], 0, sizeof(cfg_arr[slot]));
reg_base = hba->crypto_cfg_register + slot * sizeof(cfg_arr[0]);
/*
* Clear the crypto cfg on the device. Clearing CFGE
* might not be sufficient, so just clear the entire cfg.
*/
for (i = 0; i < sizeof(cfg_arr[0]); i += sizeof(__le32))
ufshcd_writel(hba, 0, reg_base + i);
wmb();
return 0;
}
static bool ufshcd_crypto_mode_supported(void *hba_p,
enum blk_crypto_mode_num crypto_mode,
unsigned int data_unit_size)
{
return ufshcd_crypto_cap_find(hba_p, crypto_mode, data_unit_size) >= 0;
}
void ufshcd_crypto_enable(struct ufs_hba *hba)
{
union ufs_crypto_cfg_entry *cfg_arr = hba->crypto_cfgs;
int slot;
if (!ufshcd_hba_is_crypto_supported(hba))
return;
hba->caps |= UFSHCD_CAP_CRYPTO;
/*
* Reset might clear all keys, so reprogram all the keys.
* Also serves to clear keys on driver init.
*/
for (slot = 0; slot < NUM_KEYSLOTS(hba); slot++)
program_key(hba, &cfg_arr[slot], slot);
}
void ufshcd_crypto_disable(struct ufs_hba *hba)
{
hba->caps &= ~UFSHCD_CAP_CRYPTO;
}
static const struct keyslot_mgmt_ll_ops ufshcd_ksm_ops = {
.keyslot_program = ufshcd_crypto_keyslot_program,
.keyslot_evict = ufshcd_crypto_keyslot_evict,
.keyslot_find = ufshcd_crypto_keyslot_find,
.crypto_mode_supported = ufshcd_crypto_mode_supported,
};
/**
* ufshcd_hba_init_crypto - Read crypto capabilities, init crypto fields in hba
* @hba: Per adapter instance
*
* Returns 0 on success. Returns -ENODEV if such capabilities don't exist, and
* -ENOMEM upon OOM.
*/
int ufshcd_hba_init_crypto(struct ufs_hba *hba)
{
int cap_idx = 0;
int err = 0;
/* Default to disabling crypto */
hba->caps &= ~UFSHCD_CAP_CRYPTO;
if (!(hba->capabilities & MASK_CRYPTO_SUPPORT)) {
err = -ENODEV;
goto out;
}
/*
* Crypto Capabilities should never be 0, because the
* config_array_ptr > 04h. So we use a 0 value to indicate that
* crypto init failed, and can't be enabled.
*/
hba->crypto_capabilities.reg_val =
cpu_to_le32(ufshcd_readl(hba, REG_UFS_CCAP));
hba->crypto_cfg_register =
(u32)hba->crypto_capabilities.config_array_ptr * 0x100;
hba->crypto_cap_array =
devm_kcalloc(hba->dev,
hba->crypto_capabilities.num_crypto_cap,
sizeof(hba->crypto_cap_array[0]),
GFP_KERNEL);
if (!hba->crypto_cap_array) {
err = -ENOMEM;
goto out;
}
hba->crypto_cfgs =
devm_kcalloc(hba->dev,
NUM_KEYSLOTS(hba),
sizeof(hba->crypto_cfgs[0]),
GFP_KERNEL);
if (!hba->crypto_cfgs) {
err = -ENOMEM;
goto out_free_cfg_mem;
}
/*
* Store all the capabilities now so that we don't need to repeatedly
* access the device each time we want to know its capabilities
*/
for (cap_idx = 0; cap_idx < hba->crypto_capabilities.num_crypto_cap;
cap_idx++) {
hba->crypto_cap_array[cap_idx].reg_val =
cpu_to_le32(ufshcd_readl(hba,
REG_UFS_CRYPTOCAP +
cap_idx * sizeof(__le32)));
}
hba->ksm = keyslot_manager_create(NUM_KEYSLOTS(hba), &ufshcd_ksm_ops,
hba);
if (!hba->ksm) {
err = -ENOMEM;
goto out_free_crypto_cfgs;
}
return 0;
out_free_crypto_cfgs:
devm_kfree(hba->dev, hba->crypto_cfgs);
out_free_cfg_mem:
devm_kfree(hba->dev, hba->crypto_cap_array);
out:
// TODO: print error?
/* Indicate that init failed by setting crypto_capabilities to 0 */
hba->crypto_capabilities.reg_val = 0;
return err;
}
void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
struct request_queue *q)
{
if (!ufshcd_hba_is_crypto_supported(hba) || !q)
return;
q->ksm = hba->ksm;
}
void ufshcd_crypto_destroy_rq_keyslot_manager(struct ufs_hba *hba,
struct request_queue *q)
{
keyslot_manager_destroy(hba->ksm);
}

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@ -0,0 +1,86 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright 2019 Google LLC
*/
#ifndef _UFSHCD_CRYPTO_H
#define _UFSHCD_CRYPTO_H
struct ufs_hba;
#ifdef CONFIG_SCSI_UFS_CRYPTO
#include <linux/keyslot-manager.h>
#include "ufshci.h"
#define NUM_KEYSLOTS(hba) (hba->crypto_capabilities.config_count + 1)
static inline bool ufshcd_keyslot_valid(struct ufs_hba *hba, unsigned int slot)
{
/*
* The actual number of configurations supported is (CFGC+1), so slot
* numbers range from 0 to config_count inclusive.
*/
return slot < NUM_KEYSLOTS(hba);
}
static inline bool ufshcd_hba_is_crypto_supported(struct ufs_hba *hba)
{
return hba->crypto_capabilities.reg_val != 0;
}
static inline bool ufshcd_is_crypto_enabled(struct ufs_hba *hba)
{
return hba->caps & UFSHCD_CAP_CRYPTO;
}
void ufshcd_crypto_enable(struct ufs_hba *hba);
void ufshcd_crypto_disable(struct ufs_hba *hba);
int ufshcd_hba_init_crypto(struct ufs_hba *hba);
void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
struct request_queue *q);
void ufshcd_crypto_destroy_rq_keyslot_manager(struct ufs_hba *hba,
struct request_queue *q);
#else /* CONFIG_SCSI_UFS_CRYPTO */
static inline bool ufshcd_keyslot_valid(struct ufs_hba *hba,
unsigned int slot)
{
return false;
}
static inline bool ufshcd_hba_is_crypto_supported(struct ufs_hba *hba)
{
return false;
}
static inline bool ufshcd_is_crypto_enabled(struct ufs_hba *hba)
{
return false;
}
static inline void ufshcd_crypto_enable(struct ufs_hba *hba) { }
static inline void ufshcd_crypto_disable(struct ufs_hba *hba) { }
static inline int ufshcd_hba_init_crypto(struct ufs_hba *hba)
{
return 0;
}
static inline void ufshcd_crypto_setup_rq_keyslot_manager(
struct ufs_hba *hba,
struct request_queue *q) { }
static inline void ufshcd_crypto_destroy_rq_keyslot_manager(
struct ufs_hba *hba,
struct request_queue *q) { }
#endif /* CONFIG_SCSI_UFS_CRYPTO */
#endif /* _UFSHCD_CRYPTO_H */

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@ -501,6 +501,11 @@ struct ufs_stats {
* @is_urgent_bkops_lvl_checked: keeps track if the urgent bkops level for
* device is known or not.
* @scsi_block_reqs_cnt: reference counting for scsi block requests
* @crypto_capabilities: Content of crypto capabilities register (0x100)
* @crypto_cap_array: Array of crypto capabilities
* @crypto_cfg_register: Start of the crypto cfg array
* @crypto_cfgs: Array of crypto configurations (i.e. config for each slot)
* @ksm: the keyslot manager tied to this hba
*/
struct ufs_hba {
void __iomem *mmio_base;
@ -713,6 +718,15 @@ struct ufs_hba {
struct rw_semaphore clk_scaling_lock;
struct ufs_desc_size desc_size;
atomic_t scsi_block_reqs_cnt;
#ifdef CONFIG_SCSI_UFS_CRYPTO
/* crypto */
union ufs_crypto_capabilities crypto_capabilities;
union ufs_crypto_cap_entry *crypto_cap_array;
u32 crypto_cfg_register;
union ufs_crypto_cfg_entry *crypto_cfgs;
struct keyslot_manager *ksm;
#endif /* CONFIG_SCSI_UFS_CRYPTO */
};
/* Returns true if clocks can be gated. Otherwise false */