diff --git a/Makefile b/Makefile
index e5535a7..1273d80 100644
--- a/Makefile
+++ b/Makefile
@@ -339,6 +339,7 @@
 
 FWLIB20_SRCS = \
 	firmware/lib20/api.c \
+	firmware/lib20/api_kernel.c \
 	firmware/lib20/common.c \
 	firmware/lib20/kernel.c \
 	firmware/lib20/misc.c \
@@ -722,6 +723,7 @@
 
 TEST20_NAMES = \
 	tests/vb20_api_tests \
+	tests/vb20_api_kernel_tests \
 	tests/vb20_common_tests \
 	tests/vb20_common2_tests \
 	tests/vb20_verify_fw.c \
@@ -1389,6 +1391,7 @@
 	${RUNTEST} ${BUILD_RUN}/tests/vb2_secdatak_tests
 	${RUNTEST} ${BUILD_RUN}/tests/vb2_sha_tests
 	${RUNTEST} ${BUILD_RUN}/tests/vb20_api_tests
+	${RUNTEST} ${BUILD_RUN}/tests/vb20_api_kernel_tests
 	${RUNTEST} ${BUILD_RUN}/tests/vb20_common_tests
 	${RUNTEST} ${BUILD_RUN}/tests/vb20_common2_tests ${TEST_KEYS}
 	${RUNTEST} ${BUILD_RUN}/tests/vb20_common3_tests ${TEST_KEYS}
diff --git a/firmware/2lib/include/2api.h b/firmware/2lib/include/2api.h
index c7367b7..95af636 100644
--- a/firmware/2lib/include/2api.h
+++ b/firmware/2lib/include/2api.h
@@ -110,7 +110,13 @@
 	 * Verified boot has changed secdatak[].  Caller must save secdatak[]
 	 * back to its underlying storage, then may clear this flag.
 	 */
-	VB2_CONTEXT_SECDATAK_CHANGED = (1 << 11),
+	VB2_CONTEXT_SECDATAK_CHANGED = (1 << 10),
+
+	/*
+	 * Allow kernel verification to roll forward the version in secdatak[].
+	 * Caller may set this flag before calling vb2api_kernel_phase3().
+	 */
+	VB2_CONTEXT_ALLOW_KERNEL_ROLL_FORWARD = (1 << 11),
 
 	/* Boot optimistically: don't touch failure counters */
 	VB2_CONTEXT_NOFAIL_BOOT = (1 << 12),
@@ -279,7 +285,57 @@
  *
  * At this point, firmware verification is done, and vb2_context contains the
  * kernel key needed to verify the kernel.  That context should be preserved
- * and passed on to kernel selection.
+ * and passed on to kernel selection.  The kernel selection process may be
+ * done by the same firmware image, or may be done by the RW firmware.  The
+ * recommended order is:
+ *
+ *	Load secdatak from wherever you keep it.
+ *
+ *      	If it wasn't there at all (for example, this is the first boot
+ *		of a new system in the factory), call vb2api_secdatak_create()
+ *		to initialize the data.
+ *
+ *		If access to your storage is unreliable (reads/writes may
+ *		contain corrupt data), you may call vb2api_secdatak_check() to
+ *		determine if the data was valid, and retry reading if it
+ *		wasn't.  (In that case, you should also read back and check the
+ *		data after any time you write it, to make sure it was written
+ *		correctly.)
+ *
+ *	Call vb2api_kernel_phase1().  At present, this decides which key to
+ *	use to verify kernel data - the recovery key from the GBB, or the
+ *	kernel subkey from the firmware verification stage.
+ *
+ *	Kernel phase 2 is finding loading, and verifying the kernel partition.
+ *
+ *	Find a boot device (you're on your own here).
+ *
+ *	Call vb2api_load_kernel_vblock() for each kernel partition on the
+ *	boot device, until one succeeds.
+ *
+ *	When that succeeds, call vb2api_get_kernel_size() to determine where
+ *	the kernel is located in the stream and how big it is.  Load or map
+ *	the kernel.  (Again, you're on your own.  This is the responsibility of
+ *	the caller so that the caller can choose whether to allocate a buffer,
+ *	load the kernel data into a predefined area of RAM, or directly map a
+ *	kernel file into the address space.  Note that technically it doesn't
+ *	matter whether the kernel data is even in the same file or stream as
+ *	the vblock, as long as the caller loads the right data.
+ *
+ *	Call vb2api_verify_kernel_data() on the kernel data.
+ *
+ *	If you ran out of kernels before finding a good one, call vb2api_fail()
+ *	with an appropriate recovery reason.
+ *
+ *	Set the VB2_CONTEXT_ALLOW_KERNEL_ROLL_FORWARD flag if the current
+ *	kernel partition has the successful flag (that is, it's already known
+ *	or assumed to be a functional kernel partition).
+ *
+ *	Call vb2api_kernel_phase3().  This cleans up from kernel verification
+ *	and updates the secure data if needed.
+ *
+ *	Lock down wherever you keep secdatak.  It should no longer be writable
+ *	this boot.
  */
 
 /**
@@ -444,6 +500,70 @@
 			  uint8_t *dest,
 			  uint32_t *dest_size);
 
+/**
+ * Prepare for kernel verification stage.
+ *
+ * Must be called before other vb2api kernel functions.
+ *
+ * @param ctx		Vboot context
+ * @return VB2_SUCCESS, or error code on error.
+ */
+int vb2api_kernel_phase1(struct vb2_context *ctx);
+
+/**
+ * Load the verified boot block (vblock) for a kernel.
+ *
+ * This function may be called multiple times, to load and verify the
+ * vblocks from multiple kernel partitions.
+ *
+ * @param ctx		Vboot context
+ * @param stream	Kernel stream
+ * @return VB2_SUCCESS, or error code on error.
+ */
+int vb2api_load_kernel_vblock(struct vb2_context *ctx);
+
+/**
+ * Get the size and offset of the kernel data for the most recent vblock.
+ *
+ * Valid after a successful call to vb2api_load_kernel_vblock().
+ *
+ * @param ctx		Vboot context
+ * @param offset_ptr	Destination for offset in bytes of kernel data as
+ *			reported by vblock.
+ * @param size_ptr      Destination for size of kernel data in bytes.
+ * @return VB2_SUCCESS, or error code on error.
+ */
+int vb2api_get_kernel_size(struct vb2_context *ctx,
+			   uint32_t *offset_ptr,
+			   uint32_t *size_ptr);
+
+/**
+ * Verify kernel data using the previously loaded kernel vblock.
+ *
+ * Valid after a successful call to vb2api_load_kernel_vblock().  This allows
+ * the caller to load or map the kernel data, as appropriate, and pass the
+ * pointer to the kernel data into vboot.
+ *
+ * @param ctx		Vboot context
+ * @param buf		Pointer to kernel data
+ * @param size		Size of kernel data in bytes
+ * @return VB2_SUCCESS, or error code on error.
+ */
+int vb2api_verify_kernel_data(struct vb2_context *ctx,
+			      const void *buf,
+			      uint32_t size);
+
+/**
+ * Clean up after kernel verification.
+ *
+ * Call this after successfully loading a vblock and verifying kernel data,
+ * or if you've run out of boot devices and/or kernel partitions.
+ *
+ * This cleans up intermediate data structures in the vboot context, and
+ * updates the version in the secure data if necessary.
+ */
+int vb2api_kernel_phase3(struct vb2_context *ctx);
+
 /*****************************************************************************/
 /* APIs provided by the caller to verified boot */
 
diff --git a/firmware/2lib/include/2recovery_reasons.h b/firmware/2lib/include/2recovery_reasons.h
index 1ced50e..7bc1f27 100644
--- a/firmware/2lib/include/2recovery_reasons.h
+++ b/firmware/2lib/include/2recovery_reasons.h
@@ -193,6 +193,12 @@
 	/* BCB related error in RW firmware */
 	VB2_RECOVERY_RW_BCB_ERROR    = 0x5c,
 
+	/* New error codes from VB2 */
+	/* TODO: may need to add strings for these in the original fwlib */
+
+	/* Secure data inititalization error */
+	VB2_RECOVERY_SECDATAK_INIT = 0x5d,
+
 	/* Unspecified/unknown error in rewritable firmware */
 	VB2_RECOVERY_RW_UNSPECIFIED  = 0x7f,
 
diff --git a/firmware/2lib/include/2return_codes.h b/firmware/2lib/include/2return_codes.h
index 848636a..40a4c28 100644
--- a/firmware/2lib/include/2return_codes.h
+++ b/firmware/2lib/include/2return_codes.h
@@ -502,6 +502,24 @@
 	/* Buffer size for the digest is too small for vb2api_get_pcr_digest */
 	VB2_ERROR_API_PCR_DIGEST_BUF,
 
+	/* Work buffer too small for recovery key in vb2api_kernel_phase1() */
+	VB2_ERROR_API_KPHASE1_WORKBUF_REC_KEY,
+
+	/* Firmware preamble not present for vb2api_kernel_phase1() */
+	VB2_ERROR_API_KPHASE1_PREAMBLE,
+
+	/* Wrong amount of kernel data in vb2api_verify_kernel_data() */
+	VB2_ERROR_API_VERIFY_KDATA_SIZE,
+
+	/* Kernel preamble not present for vb2api_verify_kernel_data() */
+	VB2_ERROR_API_VERIFY_KDATA_PREAMBLE,
+
+	/* Insufficient workbuf for hashing in vb2api_verify_kernel_data() */
+	VB2_ERROR_API_VERIFY_KDATA_WORKBUF,
+
+	/* Bad data key in vb2api_verify_kernel_data() */
+	VB2_ERROR_API_VERIFY_KDATA_KEY,
+
         /**********************************************************************
 	 * Errors which may be generated by implementations of vb2ex functions.
 	 * Implementation may also return its own specific errors, which should
diff --git a/firmware/lib20/api_kernel.c b/firmware/lib20/api_kernel.c
new file mode 100644
index 0000000..0c8b598
--- /dev/null
+++ b/firmware/lib20/api_kernel.c
@@ -0,0 +1,273 @@
+/* Copyright 2015 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.
+ *
+ * Externally-callable APIs
+ * (Kernel portion)
+ */
+
+#include "2sysincludes.h"
+#include "2api.h"
+#include "2misc.h"
+#include "2nvstorage.h"
+#include "2secdata.h"
+#include "2sha.h"
+#include "2rsa.h"
+#include "vb2_common.h"
+
+int vb2api_kernel_phase1(struct vb2_context *ctx)
+{
+	struct vb2_shared_data *sd = vb2_get_sd(ctx);
+	struct vb2_workbuf wb;
+	uint8_t *key_data;
+	uint32_t key_size;
+	int rv;
+
+	vb2_workbuf_from_ctx(ctx, &wb);
+
+	/* Initialize secure kernel data and read version */
+	rv = vb2_secdatak_init(ctx);
+	if (!rv) {
+		rv = vb2_secdatak_get(ctx, VB2_SECDATAK_VERSIONS,
+				      &sd->kernel_version_secdatak);
+	}
+
+	if (rv) {
+		if (ctx->flags & VB2_CONTEXT_RECOVERY_MODE) {
+			/* Ignore failure to get kernel version in recovery */
+			sd->kernel_version_secdatak = 0;
+		} else {
+			vb2_fail(ctx, VB2_RECOVERY_SECDATAK_INIT, rv);
+			return rv;
+		}
+	}
+
+	/* Find the key to use to verify the kernel keyblock */
+	if (ctx->flags & VB2_CONTEXT_RECOVERY_MODE) {
+		/* Recovery key from GBB */
+		struct vb2_gbb_header *gbb;
+		uint32_t key_offset;
+
+		/* Read GBB header into next chunk of work buffer */
+		gbb = vb2_workbuf_alloc(&wb, sizeof(*gbb));
+		if (!gbb)
+			return VB2_ERROR_GBB_WORKBUF;
+
+		rv = vb2_read_gbb_header(ctx, gbb);
+		if (rv)
+			return rv;
+
+		/* Only need the recovery key position and size */
+		key_offset = gbb->recovery_key_offset;
+		key_size = gbb->recovery_key_size;
+
+		/* Free the GBB header */
+		vb2_workbuf_free(&wb, sizeof(*gbb));
+
+		/* Load the recovery key itself */
+		key_data = vb2_workbuf_alloc(&wb, key_size);
+		if (!key_data)
+			return VB2_ERROR_API_KPHASE1_WORKBUF_REC_KEY;
+
+		rv = vb2ex_read_resource(ctx, VB2_RES_GBB, key_offset,
+					 key_data, key_size);
+		if (rv)
+			return rv;
+	} else {
+		/* Kernel subkey from firmware preamble */
+		struct vb2_fw_preamble *pre;
+		struct vb2_packed_key *pre_key, *packed_key;
+
+		/* Make sure we have a firmware preamble loaded */
+		if (!sd->workbuf_preamble_size)
+			return VB2_ERROR_API_KPHASE1_PREAMBLE;
+
+		pre = (struct vb2_fw_preamble *)
+			(ctx->workbuf + sd->workbuf_preamble_offset);
+		pre_key = &pre->kernel_subkey;
+
+		/*
+		 * At this point, we no longer need the packed firmware
+		 * data key, firmware preamble, or hash data.  So move the
+		 * kernel key from the preamble down after the shared data.
+		 */
+		key_data = (uint8_t *)(sd + 1);
+		packed_key = (struct vb2_packed_key *)key_data;
+		memmove(packed_key, pre_key, sizeof(*packed_key));
+		packed_key->key_offset = sizeof(*packed_key);
+		memmove(key_data + packed_key->key_offset,
+			(uint8_t *)pre_key + pre_key->key_offset,
+			pre_key->key_size);
+
+		key_size = packed_key->key_offset + packed_key->key_size;
+	}
+
+	/* Firmware stage structs are no longer present */
+	sd->workbuf_data_key_size = 0;
+	sd->workbuf_preamble_size = 0;
+	sd->workbuf_hash_size = 0;
+
+	/*
+	 * Kernel key will persist in the workbuf after we return.
+	 *
+	 * Work buffer now contains:
+	 *   - vb2_shared_data
+	 *   - kernel key
+	 */
+	sd->workbuf_kernel_key_offset =
+		vb2_offset_of(ctx->workbuf, key_data);
+	sd->workbuf_kernel_key_size = key_size;
+	ctx->workbuf_used = sd->workbuf_kernel_key_offset +
+		sd->workbuf_kernel_key_size;
+
+	return VB2_SUCCESS;
+}
+
+int vb2api_load_kernel_vblock(struct vb2_context *ctx)
+{
+	int rv;
+
+	/* Verify kernel keyblock */
+	rv = vb2_load_kernel_keyblock(ctx);
+	if (rv)
+		return rv;
+
+	/* Verify kernel preamble */
+	rv = vb2_load_kernel_preamble(ctx);
+	if (rv)
+		return rv;
+
+	return VB2_SUCCESS;
+}
+
+int vb2api_get_kernel_size(struct vb2_context *ctx,
+			   uint32_t *offset_ptr,
+			   uint32_t *size_ptr)
+{
+	struct vb2_shared_data *sd = vb2_get_sd(ctx);
+	const struct vb2_kernel_preamble *pre;
+
+	/* Get preamble pointer */
+	if (!sd->workbuf_preamble_size)
+		return VB2_ERROR_API_GET_KERNEL_SIZE_PREAMBLE;
+
+	pre = (const struct vb2_kernel_preamble *)
+		(ctx->workbuf + sd->workbuf_preamble_offset);
+
+	if (offset_ptr) {
+		/* The kernel implicitly follows the preamble */
+		*offset_ptr = sd->vblock_preamble_offset +
+			sd->workbuf_preamble_size;
+	}
+
+	if (size_ptr) {
+		/* Expect the kernel to be the size of data we signed */
+		*size_ptr = pre->body_signature.data_size;
+	}
+
+	return VB2_SUCCESS;
+}
+
+int vb2api_verify_kernel_data(struct vb2_context *ctx,
+			      const void *buf,
+			      uint32_t size)
+{
+	struct vb2_shared_data *sd = vb2_get_sd(ctx);
+	struct vb2_kernel_preamble *pre;
+	struct vb2_digest_context *dc;
+	struct vb2_public_key key;
+	struct vb2_workbuf wb;
+
+	uint8_t *digest;
+	uint32_t digest_size;
+
+	int rv;
+
+	vb2_workbuf_from_ctx(ctx, &wb);
+
+	/* Get preamble pointer */
+	if (!sd->workbuf_preamble_size)
+		return VB2_ERROR_API_VERIFY_KDATA_PREAMBLE;
+
+	pre = (struct vb2_kernel_preamble *)
+		(ctx->workbuf + sd->workbuf_preamble_offset);
+
+	/* Make sure we were passed the right amount of data */
+	if (size != pre->body_signature.data_size)
+		return VB2_ERROR_API_VERIFY_KDATA_SIZE;
+
+	/* Allocate workbuf space for the hash */
+	dc = vb2_workbuf_alloc(&wb, sizeof(*dc));
+	if (!dc)
+		return VB2_ERROR_API_VERIFY_KDATA_WORKBUF;
+
+	/*
+	 * Unpack the kernel data key to see which hashing algorithm we
+	 * should use.
+	 *
+	 * TODO: really, the kernel body should be hashed, and not signed,
+	 * because the signature we're checking is already signed as part of
+	 * the kernel preamble.  But until we can change the signing scripts,
+	 * we're stuck with a signature here instead of a hash.
+	 */
+	if (!sd->workbuf_data_key_size)
+		return VB2_ERROR_API_VERIFY_KDATA_KEY;
+
+	rv = vb2_unpack_key(&key,
+			    ctx->workbuf + sd->workbuf_data_key_offset,
+			    sd->workbuf_data_key_size);
+	if (rv)
+		return rv;
+
+	rv = vb2_digest_init(dc, key.hash_alg);
+	if (rv)
+		return rv;
+
+	rv = vb2_digest_extend(dc, buf, size);
+	if (rv)
+		return rv;
+
+	digest_size = vb2_digest_size(key.hash_alg);
+	digest = vb2_workbuf_alloc(&wb, digest_size);
+	if (!digest)
+		return VB2_ERROR_API_CHECK_HASH_WORKBUF_DIGEST;
+
+	rv = vb2_digest_finalize(dc, digest, digest_size);
+	if (rv)
+		return rv;
+
+	/*
+	 * The body signature is currently a *signature* of the body data, not
+	 * just its hash.  So we need to verify the signature.
+	 */
+
+	/*
+	 * Check digest vs. signature.  Note that this destroys the signature.
+	 * That's ok, because we only check each signature once per boot.
+	 */
+	return vb2_verify_digest(&key, &pre->body_signature, digest, &wb);
+}
+
+int vb2api_kernel_phase3(struct vb2_context *ctx)
+{
+	struct vb2_shared_data *sd = vb2_get_sd(ctx);
+	int rv;
+
+	/*
+	 * If the kernel is a newer version than in secure storage, and the
+	 * kernel signature is valid, and we're not in recovery mode, and we're
+	 * allowed to, roll forward the version in secure storage.
+	 */
+	if (sd->kernel_version > sd->kernel_version_secdatak &&
+	    (sd->flags & VB2_SD_FLAG_KERNEL_SIGNED) &&
+	    !(ctx->flags & VB2_CONTEXT_RECOVERY_MODE) &&
+	    (ctx->flags & VB2_CONTEXT_ALLOW_KERNEL_ROLL_FORWARD)) {
+		rv = vb2_secdatak_set(ctx, VB2_SECDATAK_VERSIONS,
+				      sd->kernel_version);
+		if (rv)
+			return rv;
+		sd->kernel_version_secdatak = sd->kernel_version;
+	}
+
+	return VB2_SUCCESS;
+}
diff --git a/firmware/lib20/include/vb2_struct.h b/firmware/lib20/include/vb2_struct.h
index 1e39061..f644a5f 100644
--- a/firmware/lib20/include/vb2_struct.h
+++ b/firmware/lib20/include/vb2_struct.h
@@ -219,9 +219,11 @@
 
 	/* Load address for kernel body */
 	uint64_t body_load_address;
+	/* TODO (vboot 2.1): we never used that */
 
 	/* Address of bootloader, after body is loaded at body_load_address */
 	uint64_t bootloader_address;
+	/* TODO (vboot 2.1): should be a 32-bit offset */
 
 	/* Size of bootloader in bytes */
 	uint32_t bootloader_size;
@@ -231,6 +233,14 @@
 	struct vb2_signature body_signature;
 
 	/*
+	 * TODO (vboot 2.1): fields for kernel offset and size.  Right now the
+	 * size is implicitly the same as the size of data signed by the body
+	 * signature, and the offset is implicitly at the end of the preamble.
+	 * But that forces us to pad the preamble to 64KB rather than just
+	 * having a tiny preamble and an offset field.
+	 */
+
+	/*
 	 * Fields added in header version 2.1.  You must verify the header
 	 * version before reading these fields!
 	 */
diff --git a/tests/vb20_api_kernel_tests.c b/tests/vb20_api_kernel_tests.c
new file mode 100644
index 0000000..0c8cb59
--- /dev/null
+++ b/tests/vb20_api_kernel_tests.c
@@ -0,0 +1,446 @@
+/* Copyright 2015 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.
+ *
+ * Tests for kernel verification library, api layer
+ */
+
+#include <stdio.h>
+
+#include "2sysincludes.h"
+#include "2api.h"
+#include "2common.h"
+#include "2misc.h"
+#include "2nvstorage.h"
+#include "2rsa.h"
+#include "2secdata.h"
+#include "vb2_common.h"
+#include "test_common.h"
+
+/* Common context for tests */
+static uint8_t workbuf[VB2_KERNEL_WORKBUF_RECOMMENDED_SIZE]
+	__attribute__ ((aligned (VB2_WORKBUF_ALIGN)));
+static struct vb2_workbuf wb;
+static struct vb2_context cc;
+static struct vb2_shared_data *sd;
+static struct vb2_fw_preamble *fwpre;
+static struct vb2_kernel_preamble *kpre;
+static struct vb2_packed_key *kdkey;
+static const char fw_kernel_key_data[36] = "Test kernel key data";
+static char kernel_data[0x4008] = "Sure it's a kernel...";
+
+/* Mocked function data */
+
+static struct {
+	struct vb2_gbb_header h;
+	struct vb2_packed_key recovery_key;
+	char recovery_key_data[32];
+} mock_gbb;
+
+static int mock_read_res_fail_on_call;
+static int mock_unpack_key_retval;
+static int mock_read_gbb_header_retval;
+static int mock_load_kernel_keyblock_retval;
+static int mock_load_kernel_preamble_retval;
+
+/* Type of test to reset for */
+enum reset_type {
+	FOR_PHASE1,
+	FOR_PHASE2,
+	FOR_PHASE3,
+};
+
+static void reset_common_data(enum reset_type t)
+{
+	struct vb2_packed_key *k;
+
+	memset(workbuf, 0xaa, sizeof(workbuf));
+
+	memset(&cc, 0, sizeof(cc));
+	cc.workbuf = workbuf;
+	cc.workbuf_size = sizeof(workbuf);
+	vb2_workbuf_from_ctx(&cc, &wb);
+
+	vb2_init_context(&cc);
+	sd = vb2_get_sd(&cc);
+
+	vb2_nv_init(&cc);
+
+	vb2_secdatak_create(&cc);
+	vb2_secdatak_init(&cc);
+	vb2_secdatak_set(&cc, VB2_SECDATAK_VERSIONS, 0x20002);
+
+	mock_read_res_fail_on_call = 0;
+	mock_unpack_key_retval = VB2_SUCCESS;
+	mock_read_gbb_header_retval = VB2_SUCCESS;
+	mock_load_kernel_keyblock_retval = VB2_SUCCESS;
+	mock_load_kernel_preamble_retval = VB2_SUCCESS;
+
+	/* Recovery key in mock GBB */
+	mock_gbb.recovery_key.algorithm = 11;
+	mock_gbb.recovery_key.key_offset =
+		vb2_offset_of(&mock_gbb.recovery_key,
+			      &mock_gbb.recovery_key_data);
+	mock_gbb.recovery_key.key_size = sizeof(mock_gbb.recovery_key_data);
+	strcpy(mock_gbb.recovery_key_data, "The recovery key");
+	mock_gbb.h.recovery_key_offset =
+		vb2_offset_of(&mock_gbb, &mock_gbb.recovery_key);
+	mock_gbb.h.recovery_key_size =
+		mock_gbb.recovery_key.key_offset +
+		mock_gbb.recovery_key.key_size;
+
+	if (t == FOR_PHASE1) {
+		uint8_t *kdata;
+
+		/* Create mock firmware preamble in the context */
+		sd->workbuf_preamble_offset = cc.workbuf_used;
+		fwpre = (struct vb2_fw_preamble *)
+			(cc.workbuf + sd->workbuf_preamble_offset);
+		k = &fwpre->kernel_subkey;
+		kdata = (uint8_t *)fwpre + sizeof(*fwpre);
+		memcpy(kdata, fw_kernel_key_data, sizeof(fw_kernel_key_data));
+		k->algorithm = 7;
+		k->key_offset = vb2_offset_of(k, kdata);
+		k->key_size = sizeof(fw_kernel_key_data);
+		sd->workbuf_preamble_size = sizeof(*fwpre) + k->key_size;
+		cc.workbuf_used += sd->workbuf_preamble_size;
+
+	} else if (t == FOR_PHASE2) {
+		struct vb2_signature *sig;
+		struct vb2_digest_context dc;
+		uint8_t *sdata;
+
+		/* Create mock kernel data key */
+		sd->workbuf_data_key_offset = cc.workbuf_used;
+		kdkey = (struct vb2_packed_key *)
+			(cc.workbuf + sd->workbuf_data_key_offset);
+		kdkey->algorithm = VB2_ALG_RSA2048_SHA256;
+		sd->workbuf_data_key_size = sizeof(*kdkey);
+		cc.workbuf_used += sd->workbuf_data_key_size;
+
+		/* Create mock kernel preamble in the context */
+		sd->workbuf_preamble_offset = cc.workbuf_used;
+		kpre = (struct vb2_kernel_preamble *)
+			(cc.workbuf + sd->workbuf_preamble_offset);
+		sdata = (uint8_t *)kpre + sizeof(*kpre);
+
+		sig = &kpre->body_signature;
+		sig->data_size = sizeof(kernel_data);
+		sig->sig_offset = vb2_offset_of(sig, sdata);
+		sig->sig_size = VB2_SHA512_DIGEST_SIZE;
+
+		vb2_digest_init(&dc, VB2_HASH_SHA256);
+		vb2_digest_extend(&dc, (const uint8_t *)kernel_data,
+				  sizeof(kernel_data));
+		vb2_digest_finalize(&dc, sdata, sig->sig_size);
+
+		sd->workbuf_preamble_size = sizeof(*kpre) + sig->sig_size;
+		sd->vblock_preamble_offset =
+			0x10000 - sd->workbuf_preamble_size;
+		cc.workbuf_used += sd->workbuf_preamble_size;
+
+	} else {
+		/* Set flags and versions for roll-forward */
+		sd->kernel_version = 0x20004;
+		sd->kernel_version_secdatak = 0x20002;
+		sd->flags |= VB2_SD_FLAG_KERNEL_SIGNED;
+		cc.flags |= VB2_CONTEXT_ALLOW_KERNEL_ROLL_FORWARD;
+	}
+};
+
+/* Mocked functions */
+
+int vb2ex_read_resource(struct vb2_context *ctx,
+			enum vb2_resource_index index,
+			uint32_t offset,
+			void *buf,
+			uint32_t size)
+{
+	uint8_t *rptr;
+	uint32_t rsize;
+
+	if (--mock_read_res_fail_on_call == 0)
+		return VB2_ERROR_MOCK;
+
+	switch(index) {
+	case VB2_RES_GBB:
+		rptr = (uint8_t *)&mock_gbb;
+		rsize = sizeof(mock_gbb);
+		break;
+	default:
+		return VB2_ERROR_EX_READ_RESOURCE_INDEX;
+	}
+
+	if (offset > rsize || offset + size > rsize)
+		return VB2_ERROR_EX_READ_RESOURCE_SIZE;
+
+	memcpy(buf, rptr + offset, size);
+	return VB2_SUCCESS;
+}
+
+int vb2_read_gbb_header(struct vb2_context *ctx, struct vb2_gbb_header *gbb)
+{
+	memcpy(gbb, &mock_gbb.h, sizeof(*gbb));
+	return mock_read_gbb_header_retval;
+}
+
+int vb2_load_kernel_keyblock(struct vb2_context *ctx)
+{
+	return mock_load_kernel_keyblock_retval;
+}
+
+int vb2_load_kernel_preamble(struct vb2_context *ctx)
+{
+	return mock_load_kernel_preamble_retval;
+}
+
+int vb2_unpack_key(struct vb2_public_key *key,
+		   const uint8_t *buf,
+		   uint32_t size)
+{
+	const struct vb2_packed_key *k = (const struct vb2_packed_key *)buf;
+
+	key->arrsize = 0;
+	key->hash_alg = vb2_crypto_to_hash(k->algorithm);
+	return mock_unpack_key_retval;
+}
+
+int vb2_verify_digest(const struct vb2_public_key *key,
+		      struct vb2_signature *sig,
+		      const uint8_t *digest,
+		      const struct vb2_workbuf *wb)
+{
+	if (memcmp(digest, (uint8_t *)sig + sig->sig_offset, sig->sig_size))
+		return VB2_ERROR_VDATA_VERIFY_DIGEST;
+
+	return VB2_SUCCESS;
+}
+
+/* Tests */
+
+static void phase1_tests(void)
+{
+	struct vb2_packed_key *k;
+	uint32_t old_preamble_offset;
+
+	/* Test successful call */
+	reset_common_data(FOR_PHASE1);
+	old_preamble_offset = sd->workbuf_preamble_offset;
+	TEST_SUCC(vb2api_kernel_phase1(&cc), "phase1 good");
+	TEST_EQ(sd->workbuf_preamble_size, 0, "  no more fw preamble");
+	/* Make sure normal key was loaded */
+	TEST_EQ(sd->workbuf_kernel_key_offset, old_preamble_offset,
+		"  workbuf key offset");
+	k = (struct vb2_packed_key *)
+		(cc.workbuf + sd->workbuf_kernel_key_offset);
+	TEST_EQ(sd->workbuf_kernel_key_size, k->key_offset + k->key_size,
+		"  workbuf key size");
+	TEST_EQ(cc.workbuf_used, sd->workbuf_kernel_key_offset +
+		sd->workbuf_kernel_key_size, "  workbuf used");
+	TEST_EQ(k->algorithm, 7, "  key algorithm");
+	TEST_EQ(k->key_size, sizeof(fw_kernel_key_data), "  key_size");
+	TEST_EQ(memcmp((uint8_t *)k + k->key_offset, fw_kernel_key_data,
+		       k->key_size), 0, "  key data");
+	TEST_EQ(sd->kernel_version_secdatak, 0x20002, "  secdatak version");
+
+	/* Test successful call in recovery mode */
+	reset_common_data(FOR_PHASE1);
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	/* No preamble loaded in recovery mode */
+	cc.workbuf_used = old_preamble_offset = sd->workbuf_preamble_offset;
+	sd->workbuf_preamble_offset = sd->workbuf_preamble_size = 0;
+	TEST_SUCC(vb2api_kernel_phase1(&cc), "phase1 rec good");
+	TEST_EQ(sd->workbuf_preamble_size, 0, "no more fw preamble");
+	/* Make sure recovery key was loaded */
+	TEST_EQ(sd->workbuf_kernel_key_offset, old_preamble_offset,
+		"  workbuf key offset");
+	k = (struct vb2_packed_key *)
+		(cc.workbuf + sd->workbuf_kernel_key_offset);
+	TEST_EQ(sd->workbuf_kernel_key_size, k->key_offset + k->key_size,
+		"  workbuf key size");
+	TEST_EQ(cc.workbuf_used, sd->workbuf_kernel_key_offset +
+		sd->workbuf_kernel_key_size, "  workbuf used");
+	TEST_EQ(k->algorithm, 11, "  key algorithm");
+	TEST_EQ(k->key_size, sizeof(mock_gbb.recovery_key_data), "  key_size");
+	TEST_EQ(memcmp((uint8_t *)k + k->key_offset,
+		       mock_gbb.recovery_key_data, k->key_size), 0,
+		"  key data");
+	TEST_EQ(sd->kernel_version_secdatak, 0x20002, "  secdatak version");
+
+	/* Bad secdatak causes failure in normal mode only */
+	reset_common_data(FOR_PHASE1);
+	cc.secdatak[0] ^= 0x33;
+	TEST_EQ(vb2api_kernel_phase1(&cc), VB2_ERROR_SECDATAK_CRC,
+		"phase1 bad secdata");
+	reset_common_data(FOR_PHASE1);
+
+	cc.secdatak[0] ^= 0x33;
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	TEST_SUCC(vb2api_kernel_phase1(&cc), "phase1 bad secdata rec");
+	TEST_EQ(sd->kernel_version_secdatak, 0, "  secdatak version");
+
+	/* Failures while reading recovery key */
+	reset_common_data(FOR_PHASE1);
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	cc.workbuf_used = cc.workbuf_size - sizeof(struct vb2_gbb_header) + 1;
+	TEST_EQ(vb2api_kernel_phase1(&cc), VB2_ERROR_GBB_WORKBUF,
+		"phase1 rec workbuf gbb header");
+
+	reset_common_data(FOR_PHASE1);
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	mock_read_gbb_header_retval = VB2_ERROR_MOCK;
+	TEST_EQ(vb2api_kernel_phase1(&cc), VB2_ERROR_MOCK,
+		"phase1 rec gbb read header");
+
+	reset_common_data(FOR_PHASE1);
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	mock_gbb.h.recovery_key_size = cc.workbuf_size - 1;
+	TEST_EQ(vb2api_kernel_phase1(&cc), VB2_ERROR_API_KPHASE1_WORKBUF_REC_KEY,
+		"phase1 rec workbuf key");
+
+	reset_common_data(FOR_PHASE1);
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	mock_read_res_fail_on_call = 1;
+	TEST_EQ(vb2api_kernel_phase1(&cc), VB2_ERROR_MOCK,
+		"phase1 rec gbb read key");
+
+	/* Failures while parsing subkey from firmware preamble */
+	reset_common_data(FOR_PHASE1);
+	sd->workbuf_preamble_size = 0;
+	TEST_EQ(vb2api_kernel_phase1(&cc), VB2_ERROR_API_KPHASE1_PREAMBLE,
+		"phase1 fw preamble");
+}
+
+static void load_kernel_vblock_tests(void)
+{
+	reset_common_data(FOR_PHASE1);
+	TEST_SUCC(vb2api_load_kernel_vblock(&cc), "load vblock good");
+
+	reset_common_data(FOR_PHASE1);
+	mock_load_kernel_keyblock_retval = VB2_ERROR_MOCK;
+	TEST_EQ(vb2api_load_kernel_vblock(&cc), VB2_ERROR_MOCK,
+		"load vblock bad keyblock");
+
+	reset_common_data(FOR_PHASE1);
+	mock_load_kernel_preamble_retval = VB2_ERROR_MOCK;
+	TEST_EQ(vb2api_load_kernel_vblock(&cc), VB2_ERROR_MOCK,
+		"load vblock bad preamble");
+}
+
+static void get_kernel_size_tests(void)
+{
+	uint32_t offs, size;
+
+	reset_common_data(FOR_PHASE2);
+	offs = size = 0;
+	TEST_SUCC(vb2api_get_kernel_size(&cc, &offs, &size), "get size good");
+	TEST_EQ(offs, 0x10000, "  offset");
+	TEST_EQ(size, sizeof(kernel_data), "  size");
+
+	/* Don't need to pass pointers */
+	reset_common_data(FOR_PHASE2);
+	TEST_SUCC(vb2api_get_kernel_size(&cc, NULL, NULL), "get size null");
+
+	reset_common_data(FOR_PHASE2);
+	sd->workbuf_preamble_size = 0;
+	TEST_EQ(vb2api_get_kernel_size(&cc, &offs, &size),
+		VB2_ERROR_API_GET_KERNEL_SIZE_PREAMBLE,
+		"get size no preamble");
+}
+
+static void verify_kernel_data_tests(void)
+{
+	reset_common_data(FOR_PHASE2);
+	TEST_SUCC(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		  "verify data good");
+
+	reset_common_data(FOR_PHASE2);
+	sd->workbuf_preamble_size = 0;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_API_VERIFY_KDATA_PREAMBLE, "verify no preamble");
+
+	reset_common_data(FOR_PHASE2);
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data) + 1),
+		VB2_ERROR_API_VERIFY_KDATA_SIZE, "verify size");
+
+	reset_common_data(FOR_PHASE2);
+	cc.workbuf_used = cc.workbuf_size - sizeof(struct vb2_digest_context) + 1;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_API_VERIFY_KDATA_WORKBUF, "verify workbuf");
+
+	reset_common_data(FOR_PHASE2);
+	sd->workbuf_data_key_size = 0;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_API_VERIFY_KDATA_KEY, "verify no key");
+
+	reset_common_data(FOR_PHASE2);
+	mock_unpack_key_retval = VB2_ERROR_MOCK;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_MOCK, "verify unpack key");
+
+	reset_common_data(FOR_PHASE2);
+	kdkey->algorithm = VB2_ALG_COUNT;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_SHA_INIT_ALGORITHM, "verify hash init");
+
+	reset_common_data(FOR_PHASE2);
+	cc.workbuf_used = cc.workbuf_size - sizeof(struct vb2_digest_context) - 4;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_API_CHECK_HASH_WORKBUF_DIGEST, "verify hash workbuf");
+
+	reset_common_data(FOR_PHASE2);
+	kernel_data[3] ^= 0xd0;
+	TEST_EQ(vb2api_verify_kernel_data(&cc, kernel_data, sizeof(kernel_data)),
+		VB2_ERROR_VDATA_VERIFY_DIGEST, "verify hash digest");
+	kernel_data[3] ^= 0xd0;
+}
+
+static void phase3_tests(void)
+{
+	uint32_t v;
+
+	reset_common_data(FOR_PHASE3);
+	TEST_SUCC(vb2api_kernel_phase3(&cc), "phase3 good");
+	vb2_secdatak_get(&cc, VB2_SECDATAK_VERSIONS, &v);
+	TEST_EQ(v, 0x20004, "  version");
+
+	reset_common_data(FOR_PHASE3);
+	sd->kernel_version = 0x20001;
+	TEST_SUCC(vb2api_kernel_phase3(&cc), "phase3 no rollback");
+	vb2_secdatak_get(&cc, VB2_SECDATAK_VERSIONS, &v);
+	TEST_EQ(v, 0x20002, "  version");
+
+	reset_common_data(FOR_PHASE3);
+	sd->flags &= ~VB2_SD_FLAG_KERNEL_SIGNED;
+	TEST_SUCC(vb2api_kernel_phase3(&cc), "phase3 unsigned kernel");
+	vb2_secdatak_get(&cc, VB2_SECDATAK_VERSIONS, &v);
+	TEST_EQ(v, 0x20002, "  version");
+
+	reset_common_data(FOR_PHASE3);
+	cc.flags |= VB2_CONTEXT_RECOVERY_MODE;
+	TEST_SUCC(vb2api_kernel_phase3(&cc), "phase3 recovery");
+	vb2_secdatak_get(&cc, VB2_SECDATAK_VERSIONS, &v);
+	TEST_EQ(v, 0x20002, "  version");
+
+	reset_common_data(FOR_PHASE3);
+	cc.flags &= ~VB2_CONTEXT_ALLOW_KERNEL_ROLL_FORWARD;
+	TEST_SUCC(vb2api_kernel_phase3(&cc), "phase3 no rollforward");
+	vb2_secdatak_get(&cc, VB2_SECDATAK_VERSIONS, &v);
+	TEST_EQ(v, 0x20002, "  version");
+
+	reset_common_data(FOR_PHASE3);
+	sd->status &= ~VB2_SD_STATUS_SECDATAK_INIT;
+	TEST_EQ(vb2api_kernel_phase3(&cc),
+		VB2_ERROR_SECDATAK_SET_UNINITIALIZED, "phase3 set fail");
+}
+
+int main(int argc, char* argv[])
+{
+	phase1_tests();
+	load_kernel_vblock_tests();
+	get_kernel_size_tests();
+	verify_kernel_data_tests();
+	phase3_tests();
+
+	return gTestSuccess ? 0 : 255;
+}