From 6e5f5405a2dd457aa2d46df2c22978229bbf536a Mon Sep 17 00:00:00 2001 From: Christian Hagau Date: Sun, 26 Nov 2017 00:00:00 +0000 Subject: [PATCH] Return encoded signature blob instead of a raw signature in SshAuthenticationService --- .../keychain/pgp/SshPublicKey.java | 38 +---- .../remote/SshAuthenticationService.java | 31 +++- .../ssh/signature/SshSignatureConverter.java | 138 ++++++++++++++++++ .../keychain/ssh/utils/SshUtils.java | 57 ++++++++ 4 files changed, 226 insertions(+), 38 deletions(-) create mode 100644 OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/signature/SshSignatureConverter.java create mode 100644 OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/utils/SshUtils.java diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/SshPublicKey.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/SshPublicKey.java index 94a20ba21..1bdc2774d 100644 --- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/SshPublicKey.java +++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/pgp/SshPublicKey.java @@ -27,6 +27,7 @@ import org.sufficientlysecure.keychain.ssh.key.SshDSAPublicKey; import org.sufficientlysecure.keychain.ssh.key.SshECDSAPublicKey; import org.sufficientlysecure.keychain.ssh.key.SshEd25519PublicKey; import org.sufficientlysecure.keychain.ssh.key.SshRSAPublicKey; +import org.sufficientlysecure.keychain.ssh.utils.SshUtils; public class SshPublicKey { private final static String TAG = "SshPublicKey"; @@ -66,48 +67,13 @@ public class SshPublicKey { private String encodeECKey(PGPPublicKey publicKey) { ECPublicBCPGKey publicBCPGKey = (ECPublicBCPGKey) publicKey.getPublicKeyPacket().getKey(); - String curveName = getCurveName(publicBCPGKey); + String curveName = SshUtils.getCurveName(mPublicKey.getCurveOid()); SshECDSAPublicKey sshECDSAPublicKey = new SshECDSAPublicKey(curveName, publicBCPGKey.getEncodedPoint()); return sshECDSAPublicKey.getPublicKeyBlob(); } - private String getCurveName(ECPublicBCPGKey publicBCPGKey) { - String curveOid = publicBCPGKey.getCurveOID().getId(); - // see RFC5656 section 10.{1,2} - switch (curveOid) { - // REQUIRED curves - case "1.2.840.10045.3.1.7": - return "nistp256"; - case "1.3.132.0.34": - return "nistp384"; - case "1.3.132.0.35": - return "nistp521"; - // RECOMMENDED curves - case "1.3.132.0.1": - return "1.3.132.0.1"; - case "1.2.840.10045.3.1.1": - return "1.2.840.10045.3.1.1"; - case "1.3.132.0.33": - return "1.3.132.0.33"; - case "1.3.132.0.26": - return "1.3.132.0.26"; - case "1.3.132.0.27": - return "1.3.132.0.27"; - case "1.3.132.0.16": - return "1.3.132.0.16"; - case "1.3.132.0.36": - return "1.3.132.0.36"; - case "1.3.132.0.37": - return "1.3.132.0.37"; - case "1.3.132.0.38": - return "1.3.132.0.38"; - - default: - return null; - } - } private String encodeEdDSAKey(PGPPublicKey publicKey) { EdDSAPublicBCPGKey publicBCPGKey = (EdDSAPublicBCPGKey) publicKey.getPublicKeyPacket().getKey(); diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/SshAuthenticationService.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/SshAuthenticationService.java index 4ef16eb72..8933b9f73 100644 --- a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/SshAuthenticationService.java +++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/remote/SshAuthenticationService.java @@ -23,6 +23,7 @@ import android.content.Intent; import android.os.IBinder; import android.util.Log; import org.bouncycastle.bcpg.HashAlgorithmTags; +import org.bouncycastle.bcpg.PublicKeyAlgorithmTags; import org.openintents.ssh.authentication.ISshAuthenticationService; import org.openintents.ssh.authentication.SshAuthenticationApi; import org.openintents.ssh.authentication.SshAuthenticationApiError; @@ -46,10 +47,14 @@ import org.sufficientlysecure.keychain.ssh.AuthenticationData; import org.sufficientlysecure.keychain.ssh.AuthenticationOperation; import org.sufficientlysecure.keychain.ssh.AuthenticationParcel; import org.sufficientlysecure.keychain.ssh.AuthenticationResult; +import org.sufficientlysecure.keychain.ssh.signature.SshSignatureConverter; import java.security.NoSuchAlgorithmException; import java.security.PublicKey; -import java.util.*; +import java.util.Collections; +import java.util.Date; +import java.util.HashSet; +import java.util.List; public class SshAuthenticationService extends Service { @@ -141,12 +146,22 @@ public class SshAuthenticationService extends Service { CachedPublicKeyRing cachedPublicKeyRing = mKeyRepository.getCachedPublicKeyRing(masterKeyId); long authSubKeyId; + int authSubKeyAlgorithm; + String authSubKeyCurveOid = null; try { // get first usable subkey capable of authentication authSubKeyId = cachedPublicKeyRing.getSecretAuthenticationId(); + // needed for encoding the resulting signature + authSubKeyAlgorithm = getPublicKey(masterKeyId).getAlgorithm(); + if (authSubKeyAlgorithm == PublicKeyAlgorithmTags.ECDSA) { + authSubKeyCurveOid = getPublicKey(masterKeyId).getCurveOid(); + } } catch (PgpKeyNotFoundException e) { return createExceptionErrorResult(SshAuthenticationApiError.NO_AUTH_KEY, "authentication key for master key id not found in keychain", e); + } catch (KeyRepository.NotFoundException e) { + return createExceptionErrorResult(SshAuthenticationApiError.NO_SUCH_KEY, + "Key for master key id not found", e); } authData.setAuthenticationSubKeyId(authSubKeyId); @@ -175,7 +190,19 @@ public class SshAuthenticationService extends Service { // return PendingIntent to be executed by client return packagePendingIntent(pi); } else if (authResult.success()) { - return new SigningResponse(authResult.getSignature()).toIntent(); + byte[] rawSignature = authResult.getSignature(); + byte[] sshSignature; + if (authSubKeyAlgorithm == PublicKeyAlgorithmTags.ECDSA) { + sshSignature = SshSignatureConverter.getSshSignatureEcDsa(rawSignature, authSubKeyCurveOid); + } else { + try { + sshSignature = SshSignatureConverter.getSshSignature(rawSignature, authSubKeyAlgorithm); + } catch (NoSuchAlgorithmException e) { + return createExceptionErrorResult(SshAuthenticationApiError.INTERNAL_ERROR, + "Error converting signature", e); + } + } + return new SigningResponse(sshSignature).toIntent(); } else { LogEntryParcel errorMsg = authResult.getLog().getLast(); return createErrorResult(SshAuthenticationApiError.INTERNAL_ERROR, getString(errorMsg.mType.getMsgId())); diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/signature/SshSignatureConverter.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/signature/SshSignatureConverter.java new file mode 100644 index 000000000..f08a0da31 --- /dev/null +++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/signature/SshSignatureConverter.java @@ -0,0 +1,138 @@ +/* + * Copyright (C) 2017 Christian Hagau + * + * 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 3 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, see . + */ + +package org.sufficientlysecure.keychain.ssh.signature; + +import org.bouncycastle.asn1.ASN1Integer; +import org.bouncycastle.asn1.ASN1Primitive; +import org.bouncycastle.asn1.ASN1Sequence; +import org.bouncycastle.bcpg.PublicKeyAlgorithmTags; +import org.bouncycastle.util.BigIntegers; +import org.sufficientlysecure.keychain.ssh.key.SshEncodedData; +import org.sufficientlysecure.keychain.ssh.utils.SshUtils; + +import java.io.IOException; +import java.math.BigInteger; +import java.security.NoSuchAlgorithmException; + +public class SshSignatureConverter { + + private static String getSignatureType(int algorithm) throws NoSuchAlgorithmException { + switch (algorithm) { + case PublicKeyAlgorithmTags.RSA_SIGN: + case PublicKeyAlgorithmTags.RSA_GENERAL: + return "ssh-rsa"; + + case PublicKeyAlgorithmTags.EDDSA: + return "ssh-ed25519"; + + case PublicKeyAlgorithmTags.DSA: + return "ssh-dss"; + + default: + throw new NoSuchAlgorithmException("Unknown algorithm"); + } + } + + private static byte[] getSignatureBlob(byte[] rawSignature, int algorithm) throws NoSuchAlgorithmException { + switch (algorithm) { + case PublicKeyAlgorithmTags.RSA_SIGN: + case PublicKeyAlgorithmTags.RSA_GENERAL: + return rawSignature; + + case PublicKeyAlgorithmTags.EDDSA: + return rawSignature; + + case PublicKeyAlgorithmTags.DSA: + return getDsaSignatureBlob(rawSignature); + + default: + throw new NoSuchAlgorithmException("Unknown algorithm"); + } + } + + private static byte[] getEcDsaSignatureBlob(byte[] rawSignature) { + BigInteger r = getR(rawSignature); + BigInteger s = getS(rawSignature); + + SshEncodedData rsBlob = new SshEncodedData(); + rsBlob.putMPInt(r); + rsBlob.putMPInt(s); + + return rsBlob.getBytes(); + } + + private static BigInteger getR(byte[] rawSignature) { + ASN1Sequence asn1Sequence = getASN1Sequence(rawSignature); + return ASN1Integer.getInstance(asn1Sequence.getObjectAt(0)).getValue(); + } + + private static BigInteger getS(byte[] rawSignature) { + ASN1Sequence asn1Sequence = getASN1Sequence(rawSignature); + return ASN1Integer.getInstance(asn1Sequence.getObjectAt(1)).getValue(); + } + + private static ASN1Sequence getASN1Sequence(byte[] rawSignature) { + try { + return (ASN1Sequence) ASN1Primitive.fromByteArray(rawSignature); + } catch (IOException e) { + throw new IllegalArgumentException("Could not read ASN.1 object", e); + } + } + + private static byte[] getDsaSignatureBlob(byte[] rawSignature) { + BigInteger r = getR(rawSignature); + BigInteger s = getS(rawSignature); + + byte[] rByte = BigIntegers.asUnsignedByteArray(r); + byte[] sByte = BigIntegers.asUnsignedByteArray(s); + + int integerLength = getDsaSignatureLength(rByte.length > sByte.length ? rByte.length : sByte.length); + int rPaddingLength = integerLength - rByte.length; + int sPaddingLength = integerLength - sByte.length; + + byte[] rsBlob = new byte[2 * integerLength]; + System.arraycopy(rByte, 0, rsBlob, rPaddingLength, rByte.length); + System.arraycopy(sByte, 0, rsBlob, integerLength + sPaddingLength, sByte.length); + + return rsBlob; + } + + private static int getDsaSignatureLength(int inLength) { + if (inLength <= 20) { + return 20; + } else { + return 32; + } + } + + public static byte[] getSshSignature(byte[] rawSignature, int algorithm) throws NoSuchAlgorithmException { + SshEncodedData signature = new SshEncodedData(); + signature.putString(getSignatureType(algorithm)); + signature.putString(getSignatureBlob(rawSignature, algorithm)); + + return signature.getBytes(); + } + + public static byte[] getSshSignatureEcDsa(byte[] rawSignature, String curveOid) { + SshEncodedData signature = new SshEncodedData(); + signature.putString("ecdsa-sha2-" + SshUtils.getCurveName(curveOid)); + signature.putString(getEcDsaSignatureBlob(rawSignature)); + + return signature.getBytes(); + } +} diff --git a/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/utils/SshUtils.java b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/utils/SshUtils.java new file mode 100644 index 000000000..5869a2902 --- /dev/null +++ b/OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ssh/utils/SshUtils.java @@ -0,0 +1,57 @@ +/* + * Copyright (C) 2017 Christian Hagau + * + * 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 3 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, see . + */ + +package org.sufficientlysecure.keychain.ssh.utils; + +public class SshUtils { + + public static String getCurveName(String curveOid) { + // see RFC5656 section 10.{1,2} + switch (curveOid) { + // REQUIRED curves + case "1.2.840.10045.3.1.7": + return "nistp256"; + case "1.3.132.0.34": + return "nistp384"; + case "1.3.132.0.35": + return "nistp521"; + + // RECOMMENDED curves + case "1.3.132.0.1": + return "1.3.132.0.1"; + case "1.2.840.10045.3.1.1": + return "1.2.840.10045.3.1.1"; + case "1.3.132.0.33": + return "1.3.132.0.33"; + case "1.3.132.0.26": + return "1.3.132.0.26"; + case "1.3.132.0.27": + return "1.3.132.0.27"; + case "1.3.132.0.16": + return "1.3.132.0.16"; + case "1.3.132.0.36": + return "1.3.132.0.36"; + case "1.3.132.0.37": + return "1.3.132.0.37"; + case "1.3.132.0.38": + return "1.3.132.0.38"; + + default: + return null; + } + } +}