#!/bin/bash

#
# Calculate the boot_aggregate for each TPM bank, verifying that the
# boot_aggregate in the IMA measurement list matches one of them.
#
# A software TPM may be used to verify the boot_aggregate.  If a
# software TPM is not already running on the system, this test
# starts one and initializes the TPM PCR banks by walking the sample
# binary_bios_measurements event log, included in this directory, and
# extending the TPM PCRs.  The associated ascii_runtime_measurements
# for verifying the calculated boot_aggregate is included in this
# directory as well.

trap cleanup SIGINT SIGTERM EXIT

# Base VERBOSE on the environment variable, if set.
VERBOSE="${VERBOSE:-0}"

cd "$(dirname "$0")"
export PATH=../src:$PATH
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH
. ./functions.sh
_require evmctl
TSSDIR="$(dirname -- "$(which tssstartup)")"

if [ "$(id -u)" = 0 ] && [ -c "/dev/tpm0" ]; then
	ASCII_RUNTIME_MEASUREMENTS="/sys/kernel/security/ima/ascii_runtime_measurements"
else
	BINARY_BIOS_MEASUREMENTS="./sample-binary_bios_measurements-pcrs-8-9"
	ASCII_RUNTIME_MEASUREMENTS="./sample-ascii_runtime_measurements-pcrs-8-9"
	export TPM_INTERFACE_TYPE="socsim"
	export TPM_COMMAND_PORT=2321
fi

# Only stop this test's software TPM.  Preferred method: "tsstpmcmd -stop"
cleanup() {
	if [ ! -z "${SWTPM_PPID}" ]; then
		if [ -f "${TSSDIR}/tsstpmcmd" ]; then
			"${TSSDIR}/tsstpmcmd" -stop
		else
			pkill -P "${SWTPM_PPID}"
		fi
	fi
}

# Try to start a software TPM if needed.
swtpm_start() {
	local swtpm

	swtpm="$(which tpm_server)"
	if [ -z "${swtpm}" ]; then
		echo "SKIP: Softare TPM (tpm_server) not found"
		return "$SKIP"
	fi

	pgrep tpm_server
	if [ $? -eq 0 ]; then
		echo "INFO: Software TPM (tpm_server) already running"
		return 114
	else
		echo "INFO: Starting software TPM: ${swtpm}"
		${swtpm} > /dev/null 2>&1 &
		SWTPM_PPID=$!
	fi
	return 0
}

# Initialize the software TPM using the sample binary_bios_measurements log.
swtpm_init() {
	if [ ! -f "${TSSDIR}/tssstartup" ] || [ ! -f "${TSSDIR}/tsseventextend" ]; then
		echo "SKIP: tssstartup and tsseventextend needed for test"
		return "$SKIP"
	fi

	echo "INFO: Walking ${BINARY_BIOS_MEASUREMENTS} initializing the software TPM"
	"${TSSDIR}/tssstartup"
#	$(${TSSDIR}/tsseventextend -tpm -if "${BINARY_BIOS_MEASUREMENTS}" -v) 2>&1 > /dev/null
	"${TSSDIR}/tsseventextend" -tpm -if "${BINARY_BIOS_MEASUREMENTS}" -v > /dev/null 2>&1
}

# In VERBOSE mode, display the calculated TPM PCRs for the different banks.
display_pcrs() {
	local PCRMAX=7
	local banks=("sha1" "sha256")
	local i;

	for bank in "${banks[@]}"; do
		echo "INFO: Displaying ${bank} TPM bank (PCRs 0 - 7)"
		for i in $(seq 0 $PCRMAX); do
			rc=0
			pcr=$("${TSSDIR}/tsspcrread" -halg "${bank}" -ha "${i}" -ns)
			if [ $rc -ne 0 ]; then
				echo "INFO: tsspcrread failed: $pcr"
				break
			fi
			echo "$i: $pcr"
		done
	done
}

# The first entry in the IMA measuremnet list is the "boot_aggregate".
check() {
	echo "INFO: Calculating the boot_aggregate (PCRs 0 - 7) for multiple banks"
	bootaggr=$(evmctl ima_boot_aggregate)
	if [ $? -ne 0 ]; then
		echo "SKIP: evmctl ima_boot_aggregate: $bootaggr"
		exit "$SKIP"
	fi

	boot_aggr=( $bootaggr )

	echo "INFO: Searching for the boot_aggregate in ${ASCII_RUNTIME_MEASUREMENTS}"
	for hash in "${boot_aggr[@]}"; do
		if [ "$VERBOSE" != "0" ]; then
			echo "$hash"
		fi
		if grep -q "${hash}" "${ASCII_RUNTIME_MEASUREMENTS}"; then
			echo "SUCCESS: boot_aggregate ${hash} found"
			return "$OK"
		fi
	done
	echo "FAILURE: boot_aggregate not found"
	echo "$bootaggr"
	return "$FAIL"
}

# Start and initialize a software TPM as needed
if [ "$(id -u)" != 0 ] || [ ! -c "/dev/tpm0" ]; then
	swtpm_start
	error=$?
	if [ $error -eq "$SKIP" ]; then
		echo "skip: swtpm not installed"
		exit "$SKIP"
	fi

	if [ $error -eq 0 ]; then
		swtpm_init
		if [ $? -eq "$SKIP" ]; then
			echo "testing boot_aggregate without entries"
			exit "$SKIP"
		fi
	fi
	if [ "$VERBOSE" != "0" ]; then
		display_pcrs
	fi
fi

expect_pass check