Added script to extract the digest and mrenclave from a signed enclav…

…e binary (#221)

firmware/build/extract-mrenclave

@@ -0,0 +1,67 @@
+#! /usr/bin/env bash
+
+function print_usage() {
+    echo "Usage: $0 <signed_enclave>"
+    echo "  or   $0 <unsigned_enclave> <config_file>"
+    echo ""
+    echo "Options:"
+    echo "  signed_enclave:    path of a signed enclave binary file (MUST end with '.signed' extension)."
+    echo "  unsigned_enclave:  path of an unsigned enclave binary file."
+    echo "  config_file:       configuration file specifying the enclave properties."
+    echo "                     refer to the oesign sign --help for the list of properties."
+    echo "                     this option is only required for unsigned enclaves."
+    echo ""
+    echo "Description:"
+    echo "  This script extracts the MRENCLAVE and the DIGEST values from the enclave"
+    echo "  binary and prints them to stdout. The script can be used both for unsigned"
+    echo "  and signed enclave binaries."
+    echo ""
+    echo "  Signed binaries:"
+    echo "    The MRENCLAVE and DIGEST are calculated from the signed enclave binary."
+    echo "    Both values are printed in hexadecimal format to stdout."
+    echo ""
+    echo "  Unsigned binaries:"
+    echo "    The DIGEST is calculated from the unsigned enclave binary and the enclave"
+    echo "    properties specified in the configuration file. The MRENCLAVE is set to zero."
+    echo "    Both values are printed in hexadecimal format to stdout."
+}
+
+if [[ $# -lt 1 ]]; then
+    print_usage
+    exit 1
+fi
+
+pushd $(dirname $0) > /dev/null
+BUILD_ROOT=$(pwd)
+popd > /dev/null
+
+HSM_ROOT=$(realpath $BUILD_ROOT/../../)
+
+DOCKER_IMAGE=hsm:sgx
+source $BUILD_ROOT/../../docker/check-image
+
+ENCLAVE_BIN=$(realpath $1 --relative-to=$HSM_ROOT)
+if [[ ! -f $ENCLAVE_BIN ]]; then
+    echo "Invalid enclave path: $ENCLAVE_BIN"
+    exit 1
+else
+    ENCLAVE_ARG="-e $ENCLAVE_BIN"
+fi
+
+if [[ $ENCLAVE_BIN == *.signed ]]; then
+    CONFIG_ARG=""
+elif [[ $# -ge 2 ]]; then
+    CONFIG_ARG="-c $(realpath $2 --relative-to=$HSM_ROOT)"
+else
+    echo "Invalid usage"
+    print_usage
+    exit 1
+fi
+
+DIGEST_CMD="oesign digest $ENCLAVE_ARG $CONFIG_ARG -d /tmp/enclave_digest > /dev/null && hexdump -v -e '/1 \"%02x\"' /tmp/enclave_digest"
+MRENCLAVE_CMD="oesign dump $ENCLAVE_ARG | grep mrenclave | cut -d '=' -f 2"
+EXTRACT_CMD="\$SGX_ENVSETUP && echo digest: \$($DIGEST_CMD) && echo mrenclave: \$($MRENCLAVE_CMD)"
+
+DOCKER_USER="$(id -u):$(id -g)"
+
+docker run -t --rm --user $DOCKER_USER -w /hsm2 -v ${HSM_ROOT}:/hsm2 ${DOCKER_IMAGE} /bin/bash -c "$EXTRACT_CMD"