Immediately boot into original bootloader on missing md5sum.txt

* And also silence the related error.
pbatard · Feb 27, 2024 · cf00bb3 · cf00bb3
1 parent cd4c261
commit cf00bb3
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Showing 4 changed files with 23 additions and 12 deletions.
diff --git a/src/boot.c b/src/boot.c
@@ -173,14 +173,17 @@ STATIC EFI_STATUS ExitProcess(
 	// If we have a bootloader to chain load, try to launch it
 	if (DevicePath != NULL) {
 		if (EFI_ERROR(Status) && Status != EFI_ABORTED && !IsTestMode) {
-			// Ask the user if they want to continue
-			SetText(TEXT_YELLOW);
-			PrintCentered(L"Continue with boot? [y/N]", Console.Rows - 2);
-			gST->ConIn->Reset(gST->ConIn, FALSE);
-			while (gST->ConIn->ReadKeyStroke(gST->ConIn, &Key) == EFI_NOT_READY);
-			if (Key.UnicodeChar != L'y' && Key.UnicodeChar != L'Y') {
-				SafeFree(DevicePath);
-				return Status;
+			// Ask the user if they want to continue, unless md5sum.txt could
+			// not be found, in which case continue boot right away.
+			if (Status != EFI_NOT_FOUND) {
+				SetText(TEXT_YELLOW);
+				PrintCentered(L"Continue with boot? [y/N]", Console.Rows - 2);
+				gST->ConIn->Reset(gST->ConIn, FALSE);
+				while (gST->ConIn->ReadKeyStroke(gST->ConIn, &Key) == EFI_NOT_READY);
+				if (Key.UnicodeChar != L'y' && Key.UnicodeChar != L'Y') {
+					SafeFree(DevicePath);
+					return Status;
+				}
 			}
 			RunCountDown = FALSE;
 		}
@@ -266,7 +269,10 @@ EFI_STATUS EFIAPI efi_main(
 	if (SetPathCase(Root, LoaderPath) == EFI_SUCCESS)
 		DevicePath = FileDevicePath(DeviceHandle, LoaderPath);
 
-	// Parse md5sum.txt to construct a hash list
+	// Parse md5sum.txt to construct a hash list.
+	// We parse the full file, rather than process it line by line so that we
+	// can report progress and, unless md5sum_totalbytes is always specified at
+	// the beginning, progress requires knowing how many files we have to hash.
 	Status = Parse(Root, HASH_FILE, &HashList);
 	if (EFI_ERROR(Status))
 		goto out;

diff --git a/src/boot.h b/src/boot.h
@@ -345,6 +345,7 @@ BOOLEAN IsTestSystem(VOID);
   @retval EFI_SUCCESS           The file was successfully parsed and the hash list is populated.
   @retval EFI_INVALID_PARAMETER One or more of the input parameters are invalid.
   @retval EFI_OUT_OF_RESOURCES  A memory allocation error occurred.
+  @retval EFI_NOT_FOUND         The hash list file does not exist.
   @retval EFI_UNSUPPORTED       The hash list file is too small or too large.
   @retval EFI_END_OF_FILE       The hash list file could not be read.
   @retval EFI_ABORTED           The hash list file contains invalid data.

diff --git a/src/parse.c b/src/parse.c
@@ -31,6 +31,7 @@ STATIC CONST CHAR8 TotalBytesString[] = "md5sum_totalbytes";
   @retval EFI_SUCCESS           The file was successfully parsed and the hash list is populated.
   @retval EFI_INVALID_PARAMETER One or more of the input parameters are invalid.
   @retval EFI_OUT_OF_RESOURCES  A memory allocation error occurred.
+  @retval EFI_NOT_FOUND         The hash list file does not exist.
   @retval EFI_UNSUPPORTED       The hash list file is too small or too large.
   @retval EFI_END_OF_FILE       The hash list file could not be read.
   @retval EFI_ABORTED           The hash list file contains invalid data.
@@ -55,7 +56,10 @@ EFI_STATUS Parse(
 	// Look for the hash file on the boot partition
 	Status = Root->Open(Root, &File, (CHAR16*)Path, EFI_FILE_MODE_READ, EFI_FILE_READ_ONLY);
 	if (EFI_ERROR(Status)) {
-		PrintError(L"Unable to locate '%s'", Path);
+		// A missing md5sum.txt is not really an error, so don't
+		// report it, unless we're running in test mode.
+		if (Status != EFI_NOT_FOUND || IsTestMode)
+			PrintError(L"Unable to open '%s'", Path);
 		goto out;
 	}
 

diff --git a/tests/test_list.txt b/tests/test_list.txt
@@ -1,6 +1,6 @@
-# No Hash list
+# Missing Hash list
 > rm -f image/md5sum.txt
-[FAIL] Unable to locate 'md5sum.txt': [14] Not Found
+[FAIL] Unable to open 'md5sum.txt': [14] Not Found
 
 # Empty Hash list
 > rm -f image/md5sum.txt