Handle EdDSA & DSA SSH signatures separately in SshSignatureConverter

This commit is contained in:
Christian Hagau
2018-04-27 00:00:00 +00:00
parent ff6c4d50e3
commit ba03969f7c
3 changed files with 19 additions and 36 deletions

View File

@@ -195,16 +195,18 @@ public class SshAuthenticationService extends Service {
byte[] sshSignature; byte[] sshSignature;
try { try {
switch (authSubKeyAlgorithm) { switch (authSubKeyAlgorithm) {
case PublicKeyAlgorithmTags.ECDSA: case PublicKeyAlgorithmTags.EDDSA:
sshSignature = SshSignatureConverter.getSshSignatureEcDsa(rawSignature, authSubKeyCurveOid); sshSignature = SshSignatureConverter.getSshSignatureEdDsa(rawSignature);
break; break;
case PublicKeyAlgorithmTags.RSA_SIGN: case PublicKeyAlgorithmTags.RSA_SIGN:
case PublicKeyAlgorithmTags.RSA_GENERAL: case PublicKeyAlgorithmTags.RSA_GENERAL:
sshSignature = SshSignatureConverter.getSshSignatureRsa(rawSignature, hashAlgorithmTag); sshSignature = SshSignatureConverter.getSshSignatureRsa(rawSignature, hashAlgorithmTag);
break; break;
case PublicKeyAlgorithmTags.ECDSA:
sshSignature = SshSignatureConverter.getSshSignatureEcDsa(rawSignature, authSubKeyCurveOid);
break;
case PublicKeyAlgorithmTags.DSA: case PublicKeyAlgorithmTags.DSA:
case PublicKeyAlgorithmTags.EDDSA: sshSignature = SshSignatureConverter.getSshSignatureDsa(rawSignature);
sshSignature = SshSignatureConverter.getSshSignature(rawSignature, authSubKeyAlgorithm);
break; break;
default: default:
throw new NoSuchAlgorithmException("Unknown algorithm"); throw new NoSuchAlgorithmException("Unknown algorithm");

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@@ -21,7 +21,6 @@ import org.bouncycastle.asn1.ASN1Integer;
import org.bouncycastle.asn1.ASN1Primitive; import org.bouncycastle.asn1.ASN1Primitive;
import org.bouncycastle.asn1.ASN1Sequence; import org.bouncycastle.asn1.ASN1Sequence;
import org.bouncycastle.bcpg.HashAlgorithmTags; import org.bouncycastle.bcpg.HashAlgorithmTags;
import org.bouncycastle.bcpg.PublicKeyAlgorithmTags;
import org.bouncycastle.util.BigIntegers; import org.bouncycastle.util.BigIntegers;
import org.sufficientlysecure.keychain.ssh.key.SshEncodedData; import org.sufficientlysecure.keychain.ssh.key.SshEncodedData;
import org.sufficientlysecure.keychain.ssh.utils.SshUtils; import org.sufficientlysecure.keychain.ssh.utils.SshUtils;
@@ -49,32 +48,6 @@ public class SshSignatureConverter {
} }
} }
private static String getSignatureFormatId(int algorithm) throws NoSuchAlgorithmException {
switch (algorithm) {
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.EDDSA:
return rawSignature;
case PublicKeyAlgorithmTags.DSA:
return getDsaSignatureBlob(rawSignature);
default:
throw new NoSuchAlgorithmException("Unknown algorithm");
}
}
private static byte[] getEcDsaSignatureBlob(byte[] rawSignature) { private static byte[] getEcDsaSignatureBlob(byte[] rawSignature) {
BigInteger r = getR(rawSignature); BigInteger r = getR(rawSignature);
BigInteger s = getS(rawSignature); BigInteger s = getS(rawSignature);
@@ -130,10 +103,18 @@ public class SshSignatureConverter {
} }
} }
public static byte[] getSshSignature(byte[] rawSignature, int algorithm) throws NoSuchAlgorithmException { public static byte[] getSshSignatureEdDsa(byte[] rawSignature) {
SshEncodedData signature = new SshEncodedData(); SshEncodedData signature = new SshEncodedData();
signature.putString(getSignatureFormatId(algorithm)); signature.putString("ssh-ed25519");
signature.putString(getSignatureBlob(rawSignature, algorithm)); signature.putString(rawSignature);
return signature.getBytes();
}
public static byte[] getSshSignatureDsa(byte[] rawSignature) {
SshEncodedData signature = new SshEncodedData();
signature.putString("ssh-dss");
signature.putString(getDsaSignatureBlob(rawSignature));
return signature.getBytes(); return signature.getBytes();
} }

View File

@@ -242,14 +242,14 @@ public class SshSignatureConverterTest {
@Test @Test
public void testEdDsa() throws Exception { public void testEdDsa() throws Exception {
byte[] out = SshSignatureConverter.getSshSignature(RAW_EDDSA_SIGNATURE, PublicKeyAlgorithmTags.EDDSA); byte[] out = SshSignatureConverter.getSshSignatureEdDsa(RAW_EDDSA_SIGNATURE);
Assert.assertArrayEquals(SSH_EDDSA_SIGNATURE, out); Assert.assertArrayEquals(SSH_EDDSA_SIGNATURE, out);
} }
@Test @Test
public void testDsa() throws Exception { public void testDsa() throws Exception {
byte[] out = SshSignatureConverter.getSshSignature(RAW_DSA_SIGNATURE, PublicKeyAlgorithmTags.DSA); byte[] out = SshSignatureConverter.getSshSignatureDsa(RAW_DSA_SIGNATURE);
Assert.assertArrayEquals(SSH_DSA_SIGNATURE, out); Assert.assertArrayEquals(SSH_DSA_SIGNATURE, out);
} }