Get raw secret from secure world

Use secure world to generate and maintain the file name
encryption key.

Test: vts-kernel-encryption test.

Change-Id: I3a2c093a6fdc622b106b22d324cae0519c8de7c0
Signed-off-by: Neeraj Soni <neersoni@codeaurora.org>

drivers/mmc/host/cmdq_hci-crypto-qti.c

@@ -131,19 +131,9 @@ static int cmdq_crypto_qti_derive_raw_secret(struct keyslot_manager *ksm,
 {
 	int err = 0;
 
-	if (wrapped_key_size <= RAW_SECRET_SIZE) {
-		pr_err("%s: Invalid wrapped_key_size: %u\n", __func__,
-			wrapped_key_size);
-		err = -EINVAL;
-		return err;
-	}
-	if (secret_size != RAW_SECRET_SIZE) {
-		pr_err("%s: Invalid secret size: %u\n", __func__, secret_size);
-		err = -EINVAL;
-		return err;
-	}
-	memcpy(secret, wrapped_key, secret_size);
-	return 0;
+	err = crypto_qti_derive_raw_secret(wrapped_key, wrapped_key_size,
+					   secret, secret_size);
+	return err;
 }
 
 static const struct keyslot_mgmt_ll_ops cmdq_crypto_qti_ksm_ops = {

drivers/soc/qcom/crypto-qti-common.c

@@ -461,7 +461,11 @@ int crypto_qti_derive_raw_secret(const u8 *wrapped_key,
 		return err;
 	}
 
-	memcpy(secret, wrapped_key, secret_size);
+	if (wrapped_key_size > 64)
+		err = crypto_qti_tz_raw_secret(wrapped_key, wrapped_key_size,
+				secret, secret_size);
+	else
+		memcpy(secret, wrapped_key, secret_size);
 
 	return err;
 }

drivers/soc/qcom/crypto-qti-platform.h

@@ -24,6 +24,9 @@ int crypto_qti_program_key(struct crypto_vops_qti_entry *ice_entry,
 			   unsigned int data_unit_mask, int capid);
 int crypto_qti_invalidate_key(struct crypto_vops_qti_entry *ice_entry,
 			      unsigned int slot);
+int crypto_qti_tz_raw_secret(const u8 *wrapped_key,
+			     unsigned int wrapped_key_size, u8 *secret,
+			     unsigned int secret_size);
 #else
 static inline int crypto_qti_program_key(
 				struct crypto_vops_qti_entry *ice_entry,
@@ -38,6 +41,12 @@ static inline int crypto_qti_invalidate_key(
 {
 	return 0;
 }
+static int crypto_qti_tz_raw_secret(u8 *wrapped_key,
+				    unsigned int wrapped_key_size, u8 *secret,
+				    unsigned int secret_size)
+{
+	return 0;
+}
 #endif /* CONFIG_QTI_CRYPTO_TZ */
 
 static inline void crypto_qti_disable_platform(

drivers/soc/qcom/crypto-qti-tz.c

@@ -25,6 +25,7 @@ unsigned int storage_type = SDCC_CE;
 #define ICE_BUFFER_SIZE 128
 
 static uint8_t ice_buffer[ICE_BUFFER_SIZE];
+static uint8_t secret_buffer[32];
 
 int crypto_qti_program_key(struct crypto_vops_qti_entry *ice_entry,
 			   const struct blk_crypto_key *key,
@@ -45,7 +46,7 @@ int crypto_qti_program_key(struct crypto_vops_qti_entry *ice_entry,
 	desc.arginfo = TZ_ES_CONFIG_SET_ICE_KEY_PARAM_ID;
 	desc.args[0] = slot;
 	desc.args[1] = virt_to_phys(tzbuf);
-	desc.args[2] = ICE_BUFFER_SIZE;
+	desc.args[2] = key->size;
 	desc.args[3] = ICE_CIPHER_MODE_XTS_256;
 	desc.args[4] = data_unit_mask;
 
@@ -76,6 +77,43 @@ int crypto_qti_invalidate_key(
 	return err;
 }
 
+int crypto_qti_tz_raw_secret(const u8 *wrapped_key,
+			     unsigned int wrapped_key_size, u8 *secret,
+			     unsigned int secret_size)
+{
+	int err = 0;
+	uint32_t smc_id = 0;
+
+	struct scm_desc desc = {0};
+	char *tzbuf_key, *secret_key;
+
+	tzbuf_key = ice_buffer;
+	secret_key = secret_buffer;
+	memcpy(tzbuf_key, wrapped_key, wrapped_key_size);
+	dmac_flush_range(tzbuf_key, tzbuf_key + wrapped_key_size);
+
+	smc_id = TZ_ES_RETRIEVE_RAW_SECRET_CE_TYPE_ID;
+	desc.arginfo = TZ_ES_RETRIEVE_RAW_SECRET_CE_TYPE_PARAM_ID;
+	desc.args[0] = virt_to_phys(tzbuf_key);
+	desc.args[1] = wrapped_key_size;
+	desc.args[2] = virt_to_phys(secret_key);
+	desc.args[3] = secret_size;
+
+	memset(secret_key, 0, secret_size);
+	dmac_flush_range(secret_key, secret_key + secret_size);
+
+	err = scm_call2_noretry(smc_id, &desc);
+	if (err) {
+		pr_err("%s failed to retrieve raw secret\n", __func__, err);
+		return err;
+	}
+
+	dmac_inv_range(secret_key, secret_key + secret_size);
+	memcpy(secret, secret_key, secret_size);
+
+	return err;
+}
+
 static int crypto_qti_storage_type(unsigned int *s_type)
 {
 	char boot[20] = {'\0'};

drivers/soc/qcom/crypto-qti-tz.h

@@ -19,6 +19,7 @@
 #define TZ_ES_CONFIG_SET_ICE_KEY 0x4
 #define TZ_ES_CONFIG_SET_ICE_KEY_CE_TYPE 0x5
 #define TZ_ES_INVALIDATE_ICE_KEY_CE_TYPE 0x6
+#define TZ_ES_RETRIEVE_RAW_SECRET_CE_TYPE 0x7
 
 #define TZ_ES_CONFIG_SET_ICE_KEY_CE_TYPE_ID \
 	TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_SIP, TZ_SVC_ES, \
@@ -32,6 +33,10 @@
 	TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_SIP, \
 	TZ_SVC_ES, TZ_ES_INVALIDATE_ICE_KEY_CE_TYPE)
 
+#define TZ_ES_RETRIEVE_RAW_SECRET_CE_TYPE_ID \
+	TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_SIP, \
+	TZ_SVC_ES, TZ_ES_RETRIEVE_RAW_SECRET_CE_TYPE)
+
 #define TZ_ES_INVALIDATE_ICE_KEY_ID \
 	TZ_SYSCALL_CREATE_SMC_ID(TZ_OWNER_SIP, \
 	TZ_SVC_ES, TZ_ES_INVALIDATE_ICE_KEY)
@@ -57,6 +62,11 @@
 	TZ_SYSCALL_PARAM_TYPE_VAL, TZ_SYSCALL_PARAM_TYPE_VAL, \
 	TZ_SYSCALL_PARAM_TYPE_VAL)
 
+#define TZ_ES_RETRIEVE_RAW_SECRET_CE_TYPE_PARAM_ID \
+	TZ_SYSCALL_CREATE_PARAM_ID_4( \
+	TZ_SYSCALL_PARAM_TYPE_BUF_RW, TZ_SYSCALL_PARAM_TYPE_VAL, \
+	TZ_SYSCALL_PARAM_TYPE_BUF_RW, TZ_SYSCALL_PARAM_TYPE_VAL)
+
 enum {
 	ICE_CIPHER_MODE_XTS_128 = 0,
 	ICE_CIPHER_MODE_CBC_128 = 1,