Add verified boot information and test

Add a description of how to implement verified boot using signed FIT images,
and a simple test which verifies operation on sandbox.

The test signs a FIT image and verifies it, then signs a FIT configuration
and verifies it. Then it corrupts the signature to check that this is
detected.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/test/vboot/.gitignore b/test/vboot/.gitignore
new file mode 100644
index 0000000..4631242
--- /dev/null
+++ b/test/vboot/.gitignore
@@ -0,0 +1,3 @@
+/*.dtb
+/test.fit
+/dev-keys
diff --git a/test/vboot/sandbox-kernel.dts b/test/vboot/sandbox-kernel.dts
new file mode 100644
index 0000000..a1e853c
--- /dev/null
+++ b/test/vboot/sandbox-kernel.dts
@@ -0,0 +1,7 @@
+/dts-v1/;
+
+/ {
+	model = "Sandbox Verified Boot Test";
+	compatible = "sandbox";
+
+};
diff --git a/test/vboot/sandbox-u-boot.dts b/test/vboot/sandbox-u-boot.dts
new file mode 100644
index 0000000..a1e853c
--- /dev/null
+++ b/test/vboot/sandbox-u-boot.dts
@@ -0,0 +1,7 @@
+/dts-v1/;
+
+/ {
+	model = "Sandbox Verified Boot Test";
+	compatible = "sandbox";
+
+};
diff --git a/test/vboot/sign-configs.its b/test/vboot/sign-configs.its
new file mode 100644
index 0000000..db2ed79
--- /dev/null
+++ b/test/vboot/sign-configs.its
@@ -0,0 +1,45 @@
+/dts-v1/;
+
+/ {
+	description = "Chrome OS kernel image with one or more FDT blobs";
+	#address-cells = <1>;
+
+	images {
+		kernel@1 {
+			data = /incbin/("test-kernel.bin");
+			type = "kernel_noload";
+			arch = "sandbox";
+			os = "linux";
+			compression = "none";
+			load = <0x4>;
+			entry = <0x8>;
+			kernel-version = <1>;
+			hash@1 {
+				algo = "sha1";
+			};
+		};
+		fdt@1 {
+			description = "snow";
+			data = /incbin/("sandbox-kernel.dtb");
+			type = "flat_dt";
+			arch = "sandbox";
+			compression = "none";
+			fdt-version = <1>;
+			hash@1 {
+				algo = "sha1";
+			};
+		};
+	};
+	configurations {
+		default = "conf@1";
+		conf@1 {
+			kernel = "kernel@1";
+			fdt = "fdt@1";
+			signature@1 {
+				algo = "sha1,rsa2048";
+				key-name-hint = "dev";
+				sign-images = "fdt", "kernel";
+			};
+		};
+	};
+};
diff --git a/test/vboot/sign-images.its b/test/vboot/sign-images.its
new file mode 100644
index 0000000..f69326a
--- /dev/null
+++ b/test/vboot/sign-images.its
@@ -0,0 +1,42 @@
+/dts-v1/;
+
+/ {
+	description = "Chrome OS kernel image with one or more FDT blobs";
+	#address-cells = <1>;
+
+	images {
+		kernel@1 {
+			data = /incbin/("test-kernel.bin");
+			type = "kernel_noload";
+			arch = "sandbox";
+			os = "linux";
+			compression = "none";
+			load = <0x4>;
+			entry = <0x8>;
+			kernel-version = <1>;
+			signature@1 {
+				algo = "sha1,rsa2048";
+				key-name-hint = "dev";
+			};
+		};
+		fdt@1 {
+			description = "snow";
+			data = /incbin/("sandbox-kernel.dtb");
+			type = "flat_dt";
+			arch = "sandbox";
+			compression = "none";
+			fdt-version = <1>;
+			signature@1 {
+				algo = "sha1,rsa2048";
+				key-name-hint = "dev";
+			};
+		};
+	};
+	configurations {
+		default = "conf@1";
+		conf@1 {
+			kernel = "kernel@1";
+			fdt = "fdt@1";
+		};
+	};
+};
diff --git a/test/vboot/vboot_test.sh b/test/vboot/vboot_test.sh
new file mode 100755
index 0000000..c3cfade
--- /dev/null
+++ b/test/vboot/vboot_test.sh
@@ -0,0 +1,126 @@
+#!/bin/sh
+#
+# Copyright (c) 2013, Google Inc.
+#
+# Simple Verified Boot Test Script
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+
+set -e
+
+# Run U-Boot and report the result
+# Args:
+#	$1:	Test message
+run_uboot() {
+	echo -n "Test Verified Boot Run: $1: "
+	${uboot} -d sandbox-u-boot.dtb >${tmp} -c '
+sb load host 0 100 test.fit;
+fdt addr 100;
+bootm 100;
+reset'
+	if ! grep -q "$2" ${tmp}; then
+		echo
+		echo "Verified boot key check failed, output follows:"
+		cat ${tmp}
+		false
+	else
+		echo "OK"
+	fi
+}
+
+echo "Simple Verified Boot Test"
+echo "========================="
+echo
+echo "Please see doc/uImage.FIT/verified-boot.txt for more information"
+echo
+
+err=0
+tmp=/tmp/vboot_test.$$
+
+dir=$(dirname $0)
+
+if [ -z ${O} ]; then
+	O=.
+fi
+O=$(readlink -f ${O})
+
+dtc="-I dts -O dtb -p 2000"
+uboot="${O}/u-boot"
+mkimage="${O}/tools/mkimage"
+keys="${dir}/dev-keys"
+echo ${mkimage} -D "${dtc}"
+
+echo "Build keys"
+mkdir -p ${keys}
+
+# Create an RSA key pair
+openssl genrsa -F4 -out ${keys}/dev.key 2048 2>/dev/null
+
+# Create a certificate containing the public key
+openssl req -batch -new -x509 -key ${keys}/dev.key -out ${keys}/dev.crt
+
+pushd ${dir} >/dev/null
+
+# Compile our device tree files for kernel and U-Boot (CONFIG_OF_CONTROL)
+dtc -p 0x1000 sandbox-kernel.dts -O dtb -o sandbox-kernel.dtb
+dtc -p 0x1000 sandbox-u-boot.dts -O dtb -o sandbox-u-boot.dtb
+
+# Create a number kernel image with zeroes
+head -c 5000 /dev/zero >test-kernel.bin
+
+# Build the FIT, but don't sign anything yet
+echo Build FIT with signed images
+${mkimage} -D "${dtc}" -f sign-images.its test.fit >${tmp}
+
+run_uboot "unsigned signatures:" "dev-"
+
+# Sign images with our dev keys
+echo Sign images
+${mkimage} -D "${dtc}" -F -k dev-keys -K sandbox-u-boot.dtb -r test.fit >${tmp}
+
+run_uboot "signed images" "dev+"
+
+
+# Create a fresh .dtb without the public keys
+dtc -p 0x1000 sandbox-u-boot.dts -O dtb -o sandbox-u-boot.dtb
+
+echo Build FIT with signed configuration
+${mkimage} -D "${dtc}" -f sign-configs.its test.fit >${tmp}
+
+run_uboot "unsigned config" "sha1+ OK"
+
+# Sign images with our dev keys
+echo Sign images
+${mkimage} -D "${dtc}" -F -k dev-keys -K sandbox-u-boot.dtb -r test.fit >${tmp}
+
+run_uboot "signed config" "dev+"
+
+# Increment the first byte of the signature, which should cause failure
+sig=$(fdtget -t bx test.fit /configurations/conf@1/signature@1 value)
+newbyte=$(printf %x $((0x${sig:0:2} + 1)))
+sig="${newbyte} ${sig:2}"
+fdtput -t bx test.fit /configurations/conf@1/signature@1 value ${sig}
+
+run_uboot "signed config with bad hash" "Bad Data Hash"
+
+popd >/dev/null
+
+echo
+if ${ok}; then
+	echo "Test passed"
+else
+	echo "Test failed"
+fi