cbfstool: Support CONFIG_CBFS_VERIFICATION and metadata hash anchor

This patch adds support for the new CONFIG_CBFS_VERIFICATION feature to
cbfstool. When CBFS verification is enabled, cbfstool must automatically
add a hash attribute to every CBFS file it adds (with a handful of
exceptions like bootblock and "header" pseudofiles that are never read
by coreboot code itself). It must also automatically update the metadata
hash that is embedded in the bootblock code. It will automatically find
the metadata hash by scanning the bootblock for its magic number and use
its presence to auto-detect whether CBFS verification is enabled for an
image (and which hash algorithm to use).

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I61a84add8654f60c683ef213b844a11b145a5cb7
Reviewed-on: https://review.coreboot.org/c/coreboot/+/41121
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/util/cbfstool/cbfs_glue.h b/util/cbfstool/cbfs_glue.h
new file mode 100644
index 000000000000..11786bece419
--- /dev/null
+++ b/util/cbfstool/cbfs_glue.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef _CBFS_GLUE_H_
+#define _CBFS_GLUE_H_
+
+#include "cbfs_image.h"
+
+#define CBFS_ENABLE_HASHING 1
+
+typedef const struct cbfs_image *cbfs_dev_t;
+
+static inline ssize_t cbfs_dev_read(cbfs_dev_t dev, void *buffer, size_t offset, size_t size)
+{
+	if (buffer_size(&dev->buffer) < offset ||
+	    buffer_size(&dev->buffer) - offset < size)
+		return -1;
+
+	memcpy(buffer, buffer_get(&dev->buffer) + offset, size);
+	return size;
+}
+
+static inline size_t cbfs_dev_size(cbfs_dev_t dev)
+{
+	return buffer_size(&dev->buffer);
+}
+
+#endif	/* _CBFS_GLUE_H_ */