[PATCH v2 06/10] ufs: host: wrapped keys support in ufs qcom

[Gaurav Kashyap <quic_gaurkash@quicinc.com>]

1. Implement derive software secret defined in ufs core.
2. Use the wrapped keys quirk when hwkm is supported. The assumption
   here is that if Qualcomm ICE supports HWKM, then all ICE keys
   will be treated as hardware wrapped keys.

Signed-off-by: Gaurav Kashyap <quic_gaurkash@quicinc.com>
---
 drivers/ufs/host/ufs-qcom.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/ufs/host/ufs-qcom.c b/drivers/ufs/host/ufs-qcom.c
index a04aafad4f48..9a7c5d46dbf4 100644
--- a/drivers/ufs/host/ufs-qcom.c
+++ b/drivers/ufs/host/ufs-qcom.c
@@ -82,6 +82,8 @@ static int ufs_qcom_ice_init(struct ufs_qcom_host *host)
 
 	host->ice = ice;
 	hba->caps |= UFSHCD_CAP_CRYPTO;
+	if (qcom_ice_hwkm_supported(host->ice))
+		hba->quirks |= UFSHCD_QUIRK_USES_WRAPPED_CRYPTO_KEYS;
 
 	return 0;
 }
@@ -119,7 +121,11 @@ static int ufs_qcom_ice_program_key(struct ufs_hba *hba,
 	    cap.key_size != UFS_CRYPTO_KEY_SIZE_256)
 		return -EINVAL;
 
-	ice_key_size = QCOM_ICE_CRYPTO_KEY_SIZE_256;
+	if (bkey->crypto_cfg.key_type == BLK_CRYPTO_KEY_TYPE_HW_WRAPPED)
+		ice_key_size = QCOM_ICE_CRYPTO_KEY_SIZE_WRAPPED;
+	else
+		ice_key_size = QCOM_ICE_CRYPTO_KEY_SIZE_256;
+
 	if (config_enable)
 		return qcom_ice_program_key(host->ice,
 					    QCOM_ICE_CRYPTO_ALG_AES_XTS,
@@ -129,9 +135,24 @@ static int ufs_qcom_ice_program_key(struct ufs_hba *hba,
 		return qcom_ice_evict_key(host->ice, slot);
 }
 
+/*
+ * Derive a SW secret from the wrapped key. The key is unwrapped in Trustzone
+ * and a SW key is then derived from it.
+ */
+int ufs_qcom_ice_derive_sw_secret(struct ufs_hba *hba, const u8 wrapped_key[],
+				  unsigned int wrapped_key_size,
+				  u8 sw_secret[BLK_CRYPTO_SW_SECRET_SIZE])
+{
+	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+
+	return qcom_ice_derive_sw_secret(host->ice, wrapped_key,
+					wrapped_key_size, sw_secret);
+}
+
 #else
 
 #define ufs_qcom_ice_program_key NULL
+#define ufs_qcom_ice_derive_sw_secret NULL
 
 static inline void ufs_qcom_ice_enable(struct ufs_qcom_host *host)
 {
@@ -1747,6 +1768,7 @@ static const struct ufs_hba_variant_ops ufs_hba_qcom_vops = {
 	.device_reset		= ufs_qcom_device_reset,
 	.config_scaling_param = ufs_qcom_config_scaling_param,
 	.program_key		= ufs_qcom_ice_program_key,
+	.derive_sw_secret	= ufs_qcom_ice_derive_sw_secret,
 	.reinit_notify		= ufs_qcom_reinit_notify,
 	.mcq_config_resource	= ufs_qcom_mcq_config_resource,
 	.get_hba_mac		= ufs_qcom_get_hba_mac,
-- 
2.25.1