Move dumpkey tool to the recovery repo.
The dumpkey tool is used to dump encryption keys in a custom format
used by the recovery code. Nobody else uses this format AFAICT, so
it's more appropriate to keep the code of the tool alongside the
recovery code instead of next to mincrypt.
BUG:27326256
Change-Id: I30176845617972be1d6e46e9a9218e161fbf0680
diff --git a/tools/dumpkey/Android.mk b/tools/dumpkey/Android.mk
new file mode 100644
index 0000000..bbd0656
--- /dev/null
+++ b/tools/dumpkey/Android.mk
@@ -0,0 +1,32 @@
+# Copyright (C) 2008 The Android Open Source Project
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+LOCAL_PATH := $(call my-dir)
+
+# Determine whether to build dumpkey from system/core/libmincrypt or from
+# bootable/recovery/tools. The dumpkey source is temporarily present in both
+# locations during the process of moving the tool to the recovery repository.
+# TODO(mnissler): Remove the guard after the transition is complete.
+ifndef BUILD_DUMPKEY_FROM_RECOVERY
+BUILD_DUMPKEY_FROM_RECOVERY := true
+endif
+
+ifeq ($(BUILD_DUMPKEY_FROM_RECOVERY),true)
+include $(CLEAR_VARS)
+LOCAL_MODULE := dumpkey
+LOCAL_SRC_FILES := DumpPublicKey.java
+LOCAL_JAR_MANIFEST := DumpPublicKey.mf
+LOCAL_STATIC_JAVA_LIBRARIES := bouncycastle-host
+include $(BUILD_HOST_JAVA_LIBRARY)
+endif
diff --git a/tools/dumpkey/DumpPublicKey.java b/tools/dumpkey/DumpPublicKey.java
new file mode 100644
index 0000000..3eb1398
--- /dev/null
+++ b/tools/dumpkey/DumpPublicKey.java
@@ -0,0 +1,270 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.dumpkey;
+
+import org.bouncycastle.jce.provider.BouncyCastleProvider;
+
+import java.io.FileInputStream;
+import java.math.BigInteger;
+import java.security.cert.CertificateFactory;
+import java.security.cert.X509Certificate;
+import java.security.KeyStore;
+import java.security.Key;
+import java.security.PublicKey;
+import java.security.Security;
+import java.security.interfaces.ECPublicKey;
+import java.security.interfaces.RSAPublicKey;
+import java.security.spec.ECPoint;
+
+/**
+ * Command line tool to extract RSA public keys from X.509 certificates
+ * and output source code with data initializers for the keys.
+ * @hide
+ */
+class DumpPublicKey {
+ /**
+ * @param key to perform sanity checks on
+ * @return version number of key. Supported versions are:
+ * 1: 2048-bit RSA key with e=3 and SHA-1 hash
+ * 2: 2048-bit RSA key with e=65537 and SHA-1 hash
+ * 3: 2048-bit RSA key with e=3 and SHA-256 hash
+ * 4: 2048-bit RSA key with e=65537 and SHA-256 hash
+ * @throws Exception if the key has the wrong size or public exponent
+ */
+ static int checkRSA(RSAPublicKey key, boolean useSHA256) throws Exception {
+ BigInteger pubexp = key.getPublicExponent();
+ BigInteger modulus = key.getModulus();
+ int version;
+
+ if (pubexp.equals(BigInteger.valueOf(3))) {
+ version = useSHA256 ? 3 : 1;
+ } else if (pubexp.equals(BigInteger.valueOf(65537))) {
+ version = useSHA256 ? 4 : 2;
+ } else {
+ throw new Exception("Public exponent should be 3 or 65537 but is " +
+ pubexp.toString(10) + ".");
+ }
+
+ if (modulus.bitLength() != 2048) {
+ throw new Exception("Modulus should be 2048 bits long but is " +
+ modulus.bitLength() + " bits.");
+ }
+
+ return version;
+ }
+
+ /**
+ * @param key to perform sanity checks on
+ * @return version number of key. Supported versions are:
+ * 5: 256-bit EC key with curve NIST P-256
+ * @throws Exception if the key has the wrong size or public exponent
+ */
+ static int checkEC(ECPublicKey key) throws Exception {
+ if (key.getParams().getCurve().getField().getFieldSize() != 256) {
+ throw new Exception("Curve must be NIST P-256");
+ }
+
+ return 5;
+ }
+
+ /**
+ * Perform sanity check on public key.
+ */
+ static int check(PublicKey key, boolean useSHA256) throws Exception {
+ if (key instanceof RSAPublicKey) {
+ return checkRSA((RSAPublicKey) key, useSHA256);
+ } else if (key instanceof ECPublicKey) {
+ if (!useSHA256) {
+ throw new Exception("Must use SHA-256 with EC keys!");
+ }
+ return checkEC((ECPublicKey) key);
+ } else {
+ throw new Exception("Unsupported key class: " + key.getClass().getName());
+ }
+ }
+
+ /**
+ * @param key to output
+ * @return a String representing this public key. If the key is a
+ * version 1 key, the string will be a C initializer; this is
+ * not true for newer key versions.
+ */
+ static String printRSA(RSAPublicKey key, boolean useSHA256) throws Exception {
+ int version = check(key, useSHA256);
+
+ BigInteger N = key.getModulus();
+
+ StringBuilder result = new StringBuilder();
+
+ int nwords = N.bitLength() / 32; // # of 32 bit integers in modulus
+
+ if (version > 1) {
+ result.append("v");
+ result.append(Integer.toString(version));
+ result.append(" ");
+ }
+
+ result.append("{");
+ result.append(nwords);
+
+ BigInteger B = BigInteger.valueOf(0x100000000L); // 2^32
+ BigInteger N0inv = B.subtract(N.modInverse(B)); // -1 / N[0] mod 2^32
+
+ result.append(",0x");
+ result.append(N0inv.toString(16));
+
+ BigInteger R = BigInteger.valueOf(2).pow(N.bitLength());
+ BigInteger RR = R.multiply(R).mod(N); // 2^4096 mod N
+
+ // Write out modulus as little endian array of integers.
+ result.append(",{");
+ for (int i = 0; i < nwords; ++i) {
+ long n = N.mod(B).longValue();
+ result.append(n);
+
+ if (i != nwords - 1) {
+ result.append(",");
+ }
+
+ N = N.divide(B);
+ }
+ result.append("}");
+
+ // Write R^2 as little endian array of integers.
+ result.append(",{");
+ for (int i = 0; i < nwords; ++i) {
+ long rr = RR.mod(B).longValue();
+ result.append(rr);
+
+ if (i != nwords - 1) {
+ result.append(",");
+ }
+
+ RR = RR.divide(B);
+ }
+ result.append("}");
+
+ result.append("}");
+ return result.toString();
+ }
+
+ /**
+ * @param key to output
+ * @return a String representing this public key. If the key is a
+ * version 1 key, the string will be a C initializer; this is
+ * not true for newer key versions.
+ */
+ static String printEC(ECPublicKey key) throws Exception {
+ int version = checkEC(key);
+
+ StringBuilder result = new StringBuilder();
+
+ result.append("v");
+ result.append(Integer.toString(version));
+ result.append(" ");
+
+ BigInteger X = key.getW().getAffineX();
+ BigInteger Y = key.getW().getAffineY();
+ int nbytes = key.getParams().getCurve().getField().getFieldSize() / 8; // # of 32 bit integers in X coordinate
+
+ result.append("{");
+ result.append(nbytes);
+
+ BigInteger B = BigInteger.valueOf(0x100L); // 2^8
+
+ // Write out Y coordinate as array of characters.
+ result.append(",{");
+ for (int i = 0; i < nbytes; ++i) {
+ long n = X.mod(B).longValue();
+ result.append(n);
+
+ if (i != nbytes - 1) {
+ result.append(",");
+ }
+
+ X = X.divide(B);
+ }
+ result.append("}");
+
+ // Write out Y coordinate as array of characters.
+ result.append(",{");
+ for (int i = 0; i < nbytes; ++i) {
+ long n = Y.mod(B).longValue();
+ result.append(n);
+
+ if (i != nbytes - 1) {
+ result.append(",");
+ }
+
+ Y = Y.divide(B);
+ }
+ result.append("}");
+
+ result.append("}");
+ return result.toString();
+ }
+
+ static String print(PublicKey key, boolean useSHA256) throws Exception {
+ if (key instanceof RSAPublicKey) {
+ return printRSA((RSAPublicKey) key, useSHA256);
+ } else if (key instanceof ECPublicKey) {
+ return printEC((ECPublicKey) key);
+ } else {
+ throw new Exception("Unsupported key class: " + key.getClass().getName());
+ }
+ }
+
+ public static void main(String[] args) {
+ if (args.length < 1) {
+ System.err.println("Usage: DumpPublicKey certfile ... > source.c");
+ System.exit(1);
+ }
+ Security.addProvider(new BouncyCastleProvider());
+ try {
+ for (int i = 0; i < args.length; i++) {
+ FileInputStream input = new FileInputStream(args[i]);
+ CertificateFactory cf = CertificateFactory.getInstance("X.509");
+ X509Certificate cert = (X509Certificate) cf.generateCertificate(input);
+
+ boolean useSHA256 = false;
+ String sigAlg = cert.getSigAlgName();
+ if ("SHA1withRSA".equals(sigAlg) || "MD5withRSA".equals(sigAlg)) {
+ // SignApk has historically accepted "MD5withRSA"
+ // certificates, but treated them as "SHA1withRSA"
+ // anyway. Continue to do so for backwards
+ // compatibility.
+ useSHA256 = false;
+ } else if ("SHA256withRSA".equals(sigAlg) || "SHA256withECDSA".equals(sigAlg)) {
+ useSHA256 = true;
+ } else {
+ System.err.println(args[i] + ": unsupported signature algorithm \"" +
+ sigAlg + "\"");
+ System.exit(1);
+ }
+
+ PublicKey key = cert.getPublicKey();
+ check(key, useSHA256);
+ System.out.print(print(key, useSHA256));
+ System.out.println(i < args.length - 1 ? "," : "");
+ }
+ } catch (Exception e) {
+ e.printStackTrace();
+ System.exit(1);
+ }
+ System.exit(0);
+ }
+}
diff --git a/tools/dumpkey/DumpPublicKey.mf b/tools/dumpkey/DumpPublicKey.mf
new file mode 100644
index 0000000..7bb3bc8
--- /dev/null
+++ b/tools/dumpkey/DumpPublicKey.mf
@@ -0,0 +1 @@
+Main-Class: com.android.dumpkey.DumpPublicKey