vboot: move general constants to a separate header

coreboot uses the C preprocessor on its linker scripts to
allow evaluation of macros when defining memory layout.

Move constants from 2api.h to an independent file in order
to allow for coreboot to use these constants in its memlayout
file, without needing to include the entire vboot API.

Note this commit creates two new header files:
- firmware/2lib/include/2constants.h: contains the constants
- firmware/include/vb2_constants.h: externally importable header

Also, rename VB2_WORKBUF_RECOMMENDED_SIZE to
VB2_FIRMWARE_WORKBUF_RECOMMENDED_SIZE for clarity.

BUG=b:124141368, b:124192753
TEST=Build locally
TEST=/work/vboot/src/repohooks/pre-upload.py
TEST=make clean && make runtests
TEST=make clean && COV=1 make coverage && make coverage_html
BRANCH=none

Change-Id: Id17c6955b67e51cb048b10b4be0901c0e9110a1f
Signed-off-by: Joel Kitching <kitching@google.com>
Reviewed-on: https://chromium-review.googlesource.com/1504490
Commit-Ready: Joel Kitching <kitching@chromium.org>
Tested-by: Joel Kitching <kitching@chromium.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

2 files changed, 51 insertions, 36 deletions

diff --git a/firmware/2lib/include/2api.h b/firmware/2lib/include/2api.h
index 34eb779d..f228fb30 100644
--- a/firmware/2lib/include/2api.h
+++ b/firmware/2lib/include/2api.h
@@ -22,48 +22,13 @@
 #include <stdint.h>
 
 #include "2common.h"
+#include "2constants.h"
 #include "2crypto.h"
 #include "2fw_hash_tags.h"
 #include "2id.h"
 #include "2recovery_reasons.h"
 #include "2return_codes.h"
 
-/*
- * Size of non-volatile data used by vboot.
- *
- * If you only support non-volatile data format V1, then use VB2_NVDATA_SIZE.
- * If you support V2, use VB2_NVDATA_SIZE_V2 and set context flag
- * VB2_CONTEXT_NVDATA_V2.
- */
-#define VB2_NVDATA_SIZE 16
-#define VB2_NVDATA_SIZE_V2 64
-
-/* Size of secure data spaces used by vboot */
-#define VB2_SECDATA_SIZE 10
-#define VB2_SECDATAK_SIZE 14
-
-/*
- * Recommended size of work buffer for firmware verification stage
- *
- * TODO: The recommended size really depends on which key algorithms are
- * used.  Should have a better / more accurate recommendation than this.
- */
-#define VB2_WORKBUF_RECOMMENDED_SIZE (12 * 1024)
-
-/*
- * Recommended size of work buffer for kernel verification stage
- *
- * This is bigger because vboot 2.0 kernel preambles are usually padded to
- * 64 KB.
- *
- * TODO: The recommended size really depends on which key algorithms are
- * used.  Should have a better / more accurate recommendation than this.
- */
-#define VB2_KERNEL_WORKBUF_RECOMMENDED_SIZE (80 * 1024)
-
-/* Recommended buffer size for vb2api_get_pcr_digest */
-#define VB2_PCR_DIGEST_RECOMMENDED_SIZE 32
-
 /* Flags for vb2_context.
  *
  * Unless otherwise noted, flags are set by verified boot and may be read (but
diff --git a/firmware/2lib/include/2constants.h b/firmware/2lib/include/2constants.h
new file mode 100644
index 00000000..aa9e99e2
--- /dev/null
+++ b/firmware/2lib/include/2constants.h
@@ -0,0 +1,50 @@
+/* Copyright 2019 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ * General vboot-related constants.
+ *
+ * Constants that need to be exposed to assembly files or linker scripts
+ * may be placed here and imported via vb2_constants.h.
+ */
+
+#ifndef VBOOT_REFERENCE_2CONSTANTS_H_
+#define VBOOT_REFERENCE_2CONSTANTS_H_
+
+/*
+ * Size of non-volatile data used by vboot.
+ *
+ * If you only support non-volatile data format V1, then use VB2_NVDATA_SIZE.
+ * If you support V2, use VB2_NVDATA_SIZE_V2 and set context flag
+ * VB2_CONTEXT_NVDATA_V2.
+ */
+#define VB2_NVDATA_SIZE 16
+#define VB2_NVDATA_SIZE_V2 64
+
+/* Size of secure data spaces used by vboot */
+#define VB2_SECDATA_SIZE 10
+#define VB2_SECDATAK_SIZE 14
+
+/*
+ * Recommended size of work buffer for firmware verification stage.
+ *
+ * TODO: The recommended size really depends on which key algorithms are
+ * used.  Should have a better / more accurate recommendation than this.
+ */
+#define VB2_FIRMWARE_WORKBUF_RECOMMENDED_SIZE (12 * 1024)
+
+/*
+ * Recommended size of work buffer for kernel verification stage.
+ *
+ * This is bigger because vboot 2.0 kernel preambles are usually padded to
+ * 64 KB.
+ *
+ * TODO: The recommended size really depends on which key algorithms are
+ * used.  Should have a better / more accurate recommendation than this.
+ */
+#define VB2_KERNEL_WORKBUF_RECOMMENDED_SIZE (80 * 1024)
+
+/* Recommended buffer size for vb2api_get_pcr_digest. */
+#define VB2_PCR_DIGEST_RECOMMENDED_SIZE 32
+
+#endif  /* VBOOT_REFERENCE_2CONSTANTS_H_ */