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.
Signed-off-by: Satya Tangirala <satyat@xxxxxxxxxx>
---
drivers/scsi/ufs/Kconfig | 10 +
drivers/scsi/ufs/Makefile | 1 +
drivers/scsi/ufs/ufshcd-crypto.c | 435 +++++++++++++++++++++++++++++++
drivers/scsi/ufs/ufshcd-crypto.h | 86 ++++++
drivers/scsi/ufs/ufshcd.h | 18 ++
5 files changed, 550 insertions(+)
create mode 100644 drivers/scsi/ufs/ufshcd-crypto.c
create mode 100644 drivers/scsi/ufs/ufshcd-crypto.h
diff --git a/drivers/scsi/ufs/Kconfig b/drivers/scsi/ufs/Kconfig
index 0b845ab7c3bf..861aabfe791b 100644
--- a/drivers/scsi/ufs/Kconfig
+++ b/drivers/scsi/ufs/Kconfig
@@ -150,3 +150,13 @@ config SCSI_UFS_BSG
Select this if you need a bsg device node for your UFS controller.
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.
+
diff --git a/drivers/scsi/ufs/Makefile b/drivers/scsi/ufs/Makefile
index 2a9097939bcb..094c39989a37 100644
--- a/drivers/scsi/ufs/Makefile
+++ b/drivers/scsi/ufs/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_SCSI_UFSHCD_PCI) += ufshcd-pci.o
obj-$(CONFIG_SCSI_UFSHCD_PLATFORM) += ufshcd-pltfrm.o
obj-$(CONFIG_SCSI_UFS_HISI) += ufs-hisi.o
obj-$(CONFIG_SCSI_UFS_MEDIATEK) += ufs-mediatek.o
+ufshcd-core-$(CONFIG_SCSI_UFS_CRYPTO) += ufshcd-crypto.o
diff --git a/drivers/scsi/ufs/ufshcd-crypto.c b/drivers/scsi/ufs/ufshcd-crypto.c
new file mode 100644
index 000000000000..834c57ca912a
--- /dev/null
+++ b/drivers/scsi/ufs/ufshcd-crypto.c
@@ -0,0 +1,435 @@
+// 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_crypt_mode_num crypt_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 (crypt_mode) {
+ case BLK_ENCRYPTION_MODE_AES_256_XTS:
+ ufs_alg = UFS_CRYPTO_ALG_AES_XTS;
+ ufs_key_size = UFS_CRYPTO_KEY_SIZE_256;
+ break;
+ /*
+ * case BLK_CRYPTO_ALG_BITLOCKER_AES_CBC:
+ * ufs_alg = UFS_CRYPTO_ALG_BITLOCKER_AES_CBC;
+ * break;
+ * case INLINECRYPT_ALG_AES_ECB:
+ * ufs_alg = UFS_CRYPTO_ALG_AES_ECB;
+ * break;
+ * case INLINECRYPT_ALG_ESSIV_AES_CBC:
+ * ufs_alg = UFS_CRYPTO_ALG_ESSIV_AES_CBC;
+ * break;
+ */
+ default: return -EINVAL;
+ }
+
+ data_unit_mask = get_data_unit_size_mask(data_unit_size);
+
+ /*
+ * TODO: We can replace this for loop entirely by constructing
+ * a table on init that translates blk_crypt_mode to
+ * ufs crypt alg numbers. (By assuming that each alg/keysize combo
+ * appears only once in the ufs crypto caps array.)
+ */
+ 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_crypt_mode_num crypt_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, crypt_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_crypt_mode_num crypt_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, crypt_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_crypt_mode_num crypt_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_crypt_mode_supported(void *hba_p,
+ enum blk_crypt_mode_num crypt_mode,
+ unsigned int data_unit_size)
+{
+ return ufshcd_crypto_cap_find(hba_p, crypt_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;
+}
+
+
+/**
+ * ufshcd_hba_init_crypto - Read crypto capabilities, init crypto fields in hba
+ * @hba: Per adapter instance
+ *
+ * Returns 0 on success. Returns -ENODEV if such capabilties 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,
+ hba->crypto_capabilities.config_count + 1,
+ sizeof(hba->crypto_cfgs[0]),
+ GFP_KERNEL);
+ if (!hba->crypto_cfgs) {
+ err = -ENOMEM;
+ goto out_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 = NULL;
+ mutex_init(&hba->ksm_lock);
+ hba->ksm_num_refs = 0;
+
+ return 0;
+out_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;
+}
+
+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,
+ .crypt_mode_supported = ufshcd_crypt_mode_supported,
+};
+
+void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
+ struct request_queue *q)
+{
+ if (!ufshcd_hba_is_crypto_supported(hba))
+ return;
+
+ if (q) {
+ mutex_lock(&hba->ksm_lock);
+ if (!hba->ksm) {
+ hba->ksm = keyslot_manager_create(
+ hba->crypto_capabilities.config_count + 1,
+ &ufshcd_ksm_ops, hba);
+ hba->ksm_num_refs = 0;
+ }
+ hba->ksm_num_refs++;
+ mutex_unlock(&hba->ksm_lock);
+ q->ksm = hba->ksm;
+ }
+ /*
+ * If we fail we make it look like
+ * crypto is not supported, which will avoid issues
+ * with reset
+ */
+ if (!q || !q->ksm) {
+ ufshcd_crypto_disable(hba);
+ hba->crypto_capabilities.reg_val = 0;
+ devm_kfree(hba->dev, hba->crypto_cap_array);
+ devm_kfree(hba->dev, hba->crypto_cfgs);
+ }
+}
+
+void ufshcd_crypto_destroy_rq_keyslot_manager(struct ufs_hba *hba,
+ struct request_queue *q)
+{
+ if (q && q->ksm) {
+ q->ksm = NULL;
+ mutex_lock(&hba->ksm_lock);
+ hba->ksm_num_refs--;
+ if (hba->ksm_num_refs == 0) {
+ keyslot_manager_destroy(hba->ksm);
+ hba->ksm = NULL;
+ }
+ mutex_unlock(&hba->ksm_lock);
+ }
+}
+
diff --git a/drivers/scsi/ufs/ufshcd-crypto.h b/drivers/scsi/ufs/ufshcd-crypto.h
new file mode 100644
index 000000000000..73ddc8e493fb
--- /dev/null
+++ b/drivers/scsi/ufs/ufshcd-crypto.h
@@ -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 */
diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h
index d3b6a6b57a37..ef62b3ba03fd 100644
--- a/drivers/scsi/ufs/ufshcd.h
+++ b/drivers/scsi/ufs/ufshcd.h
@@ -501,6 +501,13 @@ 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
+ * @ksm_lock: lock to protect initialization and refcount of ksm
+ * @ksm_num_refs: refcount for ksm
*/
struct ufs_hba {
void __iomem *mmio_base;
@@ -711,6 +718,17 @@ struct ufs_hba {
struct device bsg_dev;
struct request_queue *bsg_queue;
+
+#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;
+ struct mutex ksm_lock;
+ unsigned int ksm_num_refs;
+#endif /* CONFIG_SCSI_UFS_CRYPTO */
};
/* Returns true if clocks can be gated. Otherwise false */
--
2.22.0.410.gd8fdbe21b5-goog
