@Override
public Boolean doAuth(Buffer buffer, boolean init) throws Exception {
ValidateUtils.checkTrue(init, "Instance not initialized");
boolean hasSig = buffer.getBoolean();
String alg = buffer.getString();
int oldLim = buffer.wpos();
int oldPos = buffer.rpos();
int len = buffer.getInt();
buffer.wpos(buffer.rpos() + len);
PublicKey key = buffer.getRawPublicKey();
ServerFactoryManager manager = session.getFactoryManager();
Signature verif =
ValidateUtils.checkNotNull(
NamedFactory.Utils.create(manager.getSignatureFactories(), alg),
"No verifier located for algorithm=%s",
alg);
verif.initVerifier(key);
buffer.wpos(oldLim);
byte[] sig = hasSig ? buffer.getBytes() : null;
PublickeyAuthenticator authenticator =
ValidateUtils.checkNotNull(
manager.getPublickeyAuthenticator(), "No PublickeyAuthenticator configured");
if (!authenticator.authenticate(username, key, session)) {
return Boolean.FALSE;
}
if (!hasSig) {
Buffer buf = session.createBuffer(SshConstants.SSH_MSG_USERAUTH_PK_OK);
buf.putString(alg);
buf.putRawBytes(buffer.array(), oldPos, 4 + len);
session.writePacket(buf);
return null;
} else {
Buffer buf = new ByteArrayBuffer();
buf.putBytes(session.getKex().getH());
buf.putByte(SshConstants.SSH_MSG_USERAUTH_REQUEST);
buf.putString(username);
buf.putString(service);
buf.putString(UserAuthPublicKeyFactory.NAME);
buf.putBoolean(true);
buf.putString(alg);
buffer.rpos(oldPos);
buffer.wpos(oldPos + 4 + len);
buf.putBuffer(buffer);
verif.update(buf.array(), buf.rpos(), buf.available());
if (!verif.verify(sig)) {
throw new Exception("Key verification failed");
}
return Boolean.TRUE;
}
}
// TODO add 'insertXXX' methods to the Buffer class
protected Buffer insertCharacter(Buffer org, int c) {
int remaining = org.capacity();
int readPos = org.rpos();
// see if can accommodate the character in the original buffer
if ((remaining > 0) && (readPos > 0)) {
int writePos = org.wpos();
org.wpos(readPos - 1);
org.putByte((byte) c);
org.wpos(writePos);
org.rpos(readPos - 1);
return org;
} else {
Buffer buf = new ByteArrayBuffer(org.available() + Byte.SIZE, false);
buf.putByte((byte) c);
buf.putBuffer(org);
return buf;
}
}