cbfs/vboot: Adapt to new vb2_digest API

CL:3825558 changes all vb2_digest and vb2_hash functions to take a new
hwcrypto_allowed argument, to potentially let them try to call the
vb2ex_hwcrypto API for hash calculation. This change will open hardware
crypto acceleration up to all hash calculations in coreboot (most
notably CBFS verification). As part of this change, the
vb2_digest_buffer() function has been removed, so replace existing
instances in coreboot with the newer vb2_hash_calculate() API.

Due to the circular dependency of these changes with vboot, this patch
also needs to update the vboot submodule:

Updating from commit id 18cb85b5:
    2load_kernel.c: Expose load kernel as vb2_api

to commit id b827ddb9:
    tests: Ensure auxfw sync runs after EC sync

This brings in 15 new commits.

Signed-off-by: Julius Werner <jwerner@chromium.org>
Change-Id: I287d8dac3c49ad7ea3e18a015874ce8d610ec67e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/66561
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jakub Czapiga <jacz@semihalf.com>

payloads/libpayload/include/cbfs_glue.h

@@ -5,9 +5,11 @@
 
 #include <libpayload-config.h>
 #include <boot_device.h>
+#include <stdbool.h>
 #include <stdio.h>
 
 #define CBFS_ENABLE_HASHING CONFIG(LP_CBFS_VERIFICATION)
+#define CBFS_HASH_HWCRYPTO cbfs_hwcrypto_allowed()
 
 #define ERROR(...) printf("CBFS ERROR: " __VA_ARGS__)
 #define LOG(...) printf("CBFS: " __VA_ARGS__)
@@ -43,4 +45,6 @@ static inline size_t cbfs_dev_size(cbfs_dev_t dev)
 	return dev->size;
 }
 
+bool cbfs_hwcrypto_allowed(void);
+
 #endif /* _CBFS_CBFS_GLUE_H */

payloads/libpayload/libcbfs/cbfs.c

@@ -89,7 +89,7 @@ static bool cbfs_file_hash_mismatch(const void *buffer, size_t size,
 		ERROR("'%s' does not have a file hash!\n", mdata->h.filename);
 		return true;
 	}
-	if (vb2_hash_verify(buffer, size, hash) != VB2_SUCCESS) {
+	if (vb2_hash_verify(cbfs_hwcrypto_allowed(), buffer, size, hash) != VB2_SUCCESS) {
 		ERROR("'%s' file hash mismatch!\n", mdata->h.filename);
 		return true;
 	}
@@ -223,3 +223,10 @@ void *_cbfs_unverified_area_load(const char *area, const char *name, void *buf,
 
 	return do_load(&mdata, dev.offset + data_offset, buf, size_inout, true);
 }
+
+/* This should be overridden by payloads that want to enforce more explicit
+   policy on using HW crypto. */
+__weak bool cbfs_hwcrypto_allowed(void)
+{
+	return true;
+}

payloads/libpayload/tests/libcbfs/cbfs-verification-test.c

@@ -23,8 +23,10 @@ size_t vb2_digest_size(enum vb2_hash_algorithm hash_alg)
 	return VB2_SHA256_DIGEST_SIZE;
 }
 
-vb2_error_t vb2_hash_verify(const void *buf, uint32_t size, const struct vb2_hash *hash)
+vb2_error_t vb2_hash_verify(bool allow_hwcrypto, const void *buf, uint32_t size,
+			    const struct vb2_hash *hash)
 {
+	assert_true(allow_hwcrypto);
 	check_expected_ptr(buf);
 	check_expected(size);