[Review] core: add interface to load and decrypt/authenticate user TAs

Address Etienne's comments.

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>

core/arch/arm/include/kernel/user_ta.h

@@ -95,7 +95,7 @@ static inline TEE_Result tee_ta_init_user_ta_session(
 static inline TEE_Result tee_ta_register_ta_store(
 			const struct user_ta_store_ops *ops __unused)
 {
-	return TEE_SUCCESS;
+	return TEE_ERROR_NOT_SUPPORTED;
 }
 #endif
 

core/arch/arm/kernel/ree_fs_ta.c

@@ -153,10 +153,8 @@ static TEE_Result rpc_load(const TEE_UUID *uuid, struct shdr **ta,
 		return TEE_ERROR_OUT_OF_MEMORY;
 
 	*ta = phys_to_virt(phta, MEM_AREA_NSEC_SHM);
-	if (!*ta) {
-		res = TEE_ERROR_GENERIC;
-		goto out;
-	}
+	/* We don't expect NULL as thread_rpc_alloc_payload() was successful */
+	assert(*ta);
 	*cookie_ta = cta;
 	*ta_size = params[1].u.tmem.size;
 

core/arch/arm/kernel/user_ta.c

@@ -301,7 +301,7 @@ static TEE_Result ta_load(const TEE_UUID *uuid,
 	/* check input flags bitmask consistency and save flags */
 	if ((ta_head->flags & optional_flags) != ta_head->flags ||
 	    (ta_head->flags & mandatory_flags) != mandatory_flags) {
-		EMSG("TA flag issue: flags=%x optional=%X mandatory=%X",
+		EMSG("TA flag issue: flags=%x optional=%x mandatory=%x",
 		     ta_head->flags, optional_flags, mandatory_flags);
 		res = TEE_ERROR_BAD_FORMAT;
 		goto error_return;
@@ -480,7 +480,8 @@ static TEE_Result init_session_with_ta_store(const TEE_UUID *uuid,
 	res = ta_load(uuid, ta_store, &s->ctx);
 	if (res != TEE_SUCCESS)
 		return res;
-	assert(!memcmp(uuid, &s->ctx->uuid, sizeof(TEE_UUID)));
+	if (memcmp(uuid, &s->ctx->uuid, sizeof(TEE_UUID)));
+		panic();
 	return res;
 }
 

core/sub.mk

@@ -2,7 +2,7 @@ subdirs-y += kernel
 subdirs-y += tee
 subdirs-y += drivers
 
-ifeq ($(CFG_WITH_USER_TA)$(CFG_REE_FS_TA),yy)
+ifeq ($(CFG_WITH_USER_TA)-$(CFG_REE_FS_TA),y-y)
 gensrcs-y += ta_pub_key
 produce-ta_pub_key = ta_pub_key.c
 depends-ta_pub_key = $(TA_SIGN_KEY)