efi_loader: implement ConvertDeviceNodeToText

Move the logic for converting a node to text from
efi_convert_device_path_to_text to convert_device_node_to_text.

Provide a wrapper function convert_device_node_to_text_ext.

As we use only shallow device paths so we can call
directly call efi_device_node_to_text from efi_device_path_to_text.

Add output for MAC addresses.

Add output for not yet supported types/subtypes.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Signed-off-by: Alexander Graf <agraf@suse.de>

lib/efi_loader/efi_device_path_to_text.c

@@ -9,59 +9,120 @@
 #include <common.h>
 #include <efi_loader.h>
 
-#define MEDIA_DEVICE_PATH 4
-#define FILE_PATH_MEDIA_DEVICE_PATH 4
+#define MAC_OUTPUT_LEN 22
+#define UNKNOWN_OUTPUT_LEN 23
 
 const efi_guid_t efi_guid_device_path_to_text_protocol =
 		EFI_DEVICE_PATH_TO_TEXT_PROTOCOL_GUID;
 
-uint16_t *efi_convert_device_node_to_text(
+static uint16_t *efi_convert_device_node_to_text(
 		struct efi_device_path_protocol *device_node,
 		bool display_only,
 		bool allow_shortcuts)
 {
-	EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
-
-	EFI_EXIT(EFI_UNSUPPORTED);
-	return NULL;
-}
-
-uint16_t *efi_convert_device_path_to_text(
-		struct efi_device_path_protocol *device_path,
-		bool display_only,
-		bool allow_shortcuts)
-{
-	EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
-
 	unsigned long buffer_size;
 	efi_status_t r;
 	uint16_t *buffer = NULL;
+	int i;
+
+	switch (device_node->type) {
+	case DEVICE_PATH_TYPE_END:
+		return NULL;
+	case DEVICE_PATH_TYPE_MESSAGING_DEVICE:
+		switch (device_node->sub_type) {
+		case DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR: {
+			struct efi_device_path_mac_addr *dp =
+				(struct efi_device_path_mac_addr *)device_node;
 
-	switch (device_path->type) {
-	case MEDIA_DEVICE_PATH:
-		switch (device_path->sub_type) {
-		case FILE_PATH_MEDIA_DEVICE_PATH:
-			buffer_size = device_path->length - 4;
+			if (dp->if_type != 0 && dp->if_type != 1)
+				break;
+			r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES,
+					      2 * MAC_OUTPUT_LEN,
+					      (void **)&buffer);
+			if (r != EFI_SUCCESS)
+				return NULL;
+			sprintf((char *)buffer,
+				"MAC(%02x%02x%02x%02x%02x%02x,0x%1x)",
+				dp->mac.addr[0], dp->mac.addr[1],
+				dp->mac.addr[2], dp->mac.addr[3],
+				dp->mac.addr[4], dp->mac.addr[5],
+				dp->if_type);
+			for (i = MAC_OUTPUT_LEN - 1; i >= 0; --i)
+				buffer[i] = ((uint8_t *)buffer)[i];
+			break;
+			}
+		}
+	case DEVICE_PATH_TYPE_MEDIA_DEVICE:
+		switch (device_node->sub_type) {
+		case DEVICE_PATH_SUB_TYPE_FILE_PATH:
+			buffer_size = device_node->length - 4;
 			r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES,
 					      buffer_size, (void **) &buffer);
-			if (r == EFI_SUCCESS)
-				memcpy(buffer, device_path->data, buffer_size);
+			if (r != EFI_SUCCESS)
+				return NULL;
+			memcpy(buffer, device_node->data, buffer_size);
 			break;
 		}
 	}
 
-	if (buffer) {
-		EFI_EXIT(EFI_SUCCESS);
-	} else {
-		debug("type %d, subtype %d\n",
-		      device_path->type, device_path->sub_type);
-		EFI_EXIT(EFI_UNSUPPORTED);
+	/*
+	 * For all node types that we do not yet support return
+	 * 'UNKNOWN(type,subtype)'.
+	 */
+	if (!buffer) {
+		r = efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES,
+				      2 * UNKNOWN_OUTPUT_LEN,
+				      (void **)&buffer);
+		if (r != EFI_SUCCESS)
+			return NULL;
+		sprintf((char *)buffer,
+			"UNKNOWN(%04x,%04x)",
+			device_node->type,
+			device_node->sub_type);
+		for (i = UNKNOWN_OUTPUT_LEN - 1; i >= 0; --i)
+			buffer[i] = ((uint8_t *)buffer)[i];
 	}
 
 	return buffer;
 }
 
+static uint16_t EFIAPI *efi_convert_device_node_to_text_ext(
+		struct efi_device_path_protocol *device_node,
+		bool display_only,
+		bool allow_shortcuts)
+{
+	uint16_t *buffer;
+
+	EFI_ENTRY("%p, %d, %d", device_node, display_only, allow_shortcuts);
+
+	buffer = efi_convert_device_node_to_text(device_node, display_only,
+						 allow_shortcuts);
+
+	EFI_EXIT(EFI_SUCCESS);
+	return buffer;
+}
+
+static uint16_t EFIAPI *efi_convert_device_path_to_text(
+		struct efi_device_path_protocol *device_path,
+		bool display_only,
+		bool allow_shortcuts)
+{
+	uint16_t *buffer;
+
+	EFI_ENTRY("%p, %d, %d", device_path, display_only, allow_shortcuts);
+
+	/*
+	 * Our device paths are all of depth one. So its is sufficient to
+	 * to convert the first node.
+	 */
+	buffer = efi_convert_device_node_to_text(device_path, display_only,
+						 allow_shortcuts);
+
+	EFI_EXIT(EFI_SUCCESS);
+	return buffer;
+}
+
 const struct efi_device_path_to_text_protocol efi_device_path_to_text = {
-	.convert_device_node_to_text = efi_convert_device_node_to_text,
+	.convert_device_node_to_text = efi_convert_device_node_to_text_ext,
 	.convert_device_path_to_text = efi_convert_device_path_to_text,
 };