library_manager: auth: Add library authentication mechanizm

This patch adds usage of authentication API to check
library signature. If feature enabled it will block loading of
library without valid signature.

Signed-off-by: Jaroslaw Stelter <Jaroslaw.Stelter@intel.com>

src/include/sof/lib_manager.h

@@ -64,6 +64,9 @@
 
 #include <stdint.h>
 #include <rimage/sof/user/manifest.h>
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+#include <sof/auth_api_iface.h>
+#endif
 
 #define LIB_MANAGER_MAX_LIBS				16
 #define LIB_MANAGER_LIB_ID_SHIFT			12
@@ -86,6 +89,10 @@ struct ext_library {
 	uint32_t lib_notif_count;
 
 	void *runtime_data;
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+	struct auth_api_ctx auth_ctx;
+	void *auth_buffer;
+#endif
 };
 
 /* lib manager context, used by lib_notification */

src/library_manager/Kconfig

@@ -13,4 +13,14 @@ config LIBRARY_MANAGER
 	  Externally developed modules both for SOF and Zephyr
 	  could be used if enabled.
 	  If unsure say N.
+
+config LIBRARY_AUTH_SUPPORT
+	bool "Library Authentication Support"
+	default n
+	help
+	  This is support for dynamic modules authentication.
+	  Externally developed modules both for SOF and Zephyr
+	  could be used if enabled.
+	  If unsure say N.
+
 endmenu

src/library_manager/lib_manager.c

@@ -25,6 +25,10 @@
 #include <zephyr/cache.h>
 #include <zephyr/drivers/mm/system_mm.h>
 
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+#include <auth/auth_api.h>
+#endif
+
 #include <errno.h>
 #include <stdbool.h>
 #include <stddef.h>
@@ -47,6 +51,74 @@ struct lib_manager_dma_ext {
 
 static struct ext_library loader_ext_lib;
 
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+static int lib_manager_auth_init(void)
+{
+	struct ext_library *ext_lib = ext_lib_get();
+	int ret;
+
+	if (auth_api_version().major != AUTH_API_VERSION_MAJOR)
+		return -EINVAL;
+
+	ext_lib->auth_buffer = rballoc_align(0, SOF_MEM_CAPS_RAM,
+					     AUTH_SCRATCH_BUFF_SZ, CONFIG_MM_DRV_PAGE_SIZE);
+	if (!ext_lib->auth_buffer)
+		return -ENOMEM;
+
+	ret = auth_api_init(&ext_lib->auth_ctx, ext_lib->auth_buffer,
+			    AUTH_SCRATCH_BUFF_SZ, IMG_TYPE_LIB);
+	if (ret != 0) {
+		tr_err(&lib_manager_tr, "lib_manager_auth_init() failed with error: %d", ret);
+		rfree(ext_lib->auth_buffer);
+		ret = -EACCES;
+	}
+
+	return ret;
+}
+
+static void lib_manager_auth_deinit(void)
+{
+	struct ext_library *ext_lib = ext_lib_get();
+
+	if (ext_lib->auth_buffer)
+		memset(ext_lib->auth_buffer, 0, AUTH_SCRATCH_BUFF_SZ);
+
+	rfree(ext_lib->auth_buffer);
+	ext_lib->auth_buffer = NULL;
+	memset(&ext_lib->auth_ctx, 0, sizeof(struct auth_api_ctx));
+}
+
+static int lib_manager_auth_proc(const void *buffer_data,
+				 size_t buffer_size, enum auth_phase phase)
+{
+	struct ext_library *ext_lib = ext_lib_get();
+	int ret;
+
+	ret = auth_api_init_auth_proc(&ext_lib->auth_ctx, buffer_data, buffer_size, phase);
+
+	if (ret != 0) {
+		tr_err(&lib_manager_tr, "lib_manager_auth_proc() failed with error: %d", ret);
+		return -ENOTSUP;
+	}
+
+	/* The auth_api_busy() will timeouts internally in case of failure */
+	while (auth_api_busy(&ext_lib->auth_ctx))
+		;
+
+	ret = auth_api_result(&ext_lib->auth_ctx);
+
+	if (ret != AUTH_IMAGE_TRUSTED) {
+		tr_err(&lib_manager_tr, "lib_manager_auth_proc() Untrasted library!");
+		return -EACCES;
+	}
+
+	if (phase == AUTH_PHASE_LAST)
+		auth_api_cleanup(&ext_lib->auth_ctx);
+
+	return 0;
+}
+#endif /* CONFIG_LIBRARY_AUTH_SUPPORT */
+
 #if IS_ENABLED(CONFIG_MM_DRV)
 
 #define PAGE_SZ		CONFIG_MM_DRV_PAGE_SIZE
@@ -578,6 +650,16 @@ static int lib_manager_store_library(struct lib_manager_dma_ext *dma_ext,
 	tr_dbg(&lib_manager_tr, "lib_manager_store_library(): pointer: %p",
 	       (__sparse_force void *)library_base_address);
 
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+	/* AUTH_PHASE_FIRST - checks library manifest only. */
+	ret = lib_manager_auth_proc((__sparse_force void *)man_buffer,
+				    MAN_MAX_SIZE_V1_8, AUTH_PHASE_FIRST);
+	if (ret < 0) {
+		rfree((__sparse_force void *)library_base_address);
+		return ret;
+	}
+#endif /* CONFIG_LIBRARY_AUTH_SUPPORT */
+
 	/* Copy data from temp_mft_buf to destination memory (pointed by library_base_address) */
 	memcpy_s((__sparse_force void *)library_base_address, MAN_MAX_SIZE_V1_8,
 		 (__sparse_force void *)man_buffer, MAN_MAX_SIZE_V1_8);
@@ -590,6 +672,16 @@ static int lib_manager_store_library(struct lib_manager_dma_ext *dma_ext,
 		return ret;
 	}
 
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+	/* AUTH_PHASE_LAST - do final library authentication checks */
+	ret = lib_manager_auth_proc((__sparse_force void *)library_base_address,
+				    preload_size - MAN_MAX_SIZE_V1_8, AUTH_PHASE_LAST);
+	if (ret < 0) {
+		rfree((__sparse_force void *)library_base_address);
+		return ret;
+	}
+#endif /* CONFIG_LIBRARY_AUTH_SUPPORT */
+
 	/* Now update sof context with new library */
 	lib_manager_update_sof_ctx((__sparse_force void *)library_base_address, lib_id);
 
@@ -699,7 +791,7 @@ int lib_manager_load_library(uint32_t dma_id, uint32_t lib_id, uint32_t type)
 	/* allocate temporary manifest buffer */
 	man_tmp_buffer = (__sparse_force void __sparse_cache *)
 			rballoc_align(0, SOF_MEM_CAPS_DMA,
-				      MAN_MAX_SIZE_V1_8, dma_ext->addr_align);
+				      MAN_MAX_SIZE_V1_8, CONFIG_MM_DRV_PAGE_SIZE);
 	if (!man_tmp_buffer) {
 		ret = -ENOMEM;
 		goto cleanup;
@@ -710,8 +802,19 @@ int lib_manager_load_library(uint32_t dma_id, uint32_t lib_id, uint32_t type)
 	if (ret < 0)
 		goto stop_dma;
 
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+	/* Initialize authentication support */
+	ret = lib_manager_auth_init();
+	if (ret < 0)
+		goto stop_dma;
+#endif /* CONFIG_LIBRARY_AUTH_SUPPORT */
+
 	ret = lib_manager_store_library(dma_ext, man_tmp_buffer, lib_id);
 
+#if CONFIG_LIBRARY_AUTH_SUPPORT
+	lib_manager_auth_deinit();
+#endif /* CONFIG_LIBRARY_AUTH_SUPPORT */
+
 stop_dma:
 	ret2 = dma_stop(dma_ext->chan->dma->z_dev, dma_ext->chan->index);
 	if (ret2 < 0) {