2 files changed, 418 insertions, 0 deletions

diff --git a/src/Protocol/Authenticator.cpp b/src/Protocol/Authenticator.cpp
new file mode 100644
index 000000000..ba435e9ce
--- /dev/null
+++ b/src/Protocol/Authenticator.cpp
@@ -0,0 +1,325 @@
+
+#include "Globals.h"  // NOTE: MSVC stupidness requires this to be the same across all modules
+
+#include "Authenticator.h"
+#include "OSSupport/BlockingTCPLink.h"
+#include "Root.h"
+#include "Server.h"
+
+#include "inifile/iniFile.h"
+#include "json/json.h"
+
+#include "polarssl/config.h"
+#include "polarssl/net.h"
+#include "polarssl/ssl.h"
+#include "polarssl/entropy.h"
+#include "polarssl/ctr_drbg.h"
+#include "polarssl/error.h"
+#include "polarssl/certs.h"
+
+#include <sstream>
+#include <iomanip>
+
+
+
+
+
+#define DEFAULT_AUTH_SERVER "sessionserver.mojang.com"
+#define DEFAULT_AUTH_ADDRESS "/session/minecraft/hasJoined?username=%USERNAME%&serverId=%SERVERID%"
+#define MAX_REDIRECTS 10
+
+
+
+
+
+cAuthenticator::cAuthenticator(void) :
+super("cAuthenticator"),
+m_Server(DEFAULT_AUTH_SERVER),
+m_Address(DEFAULT_AUTH_ADDRESS),
+m_ShouldAuthenticate(true)
+{
+}
+
+
+
+
+
+cAuthenticator::~cAuthenticator()
+{
+	Stop();
+}
+
+
+
+
+
+void cAuthenticator::ReadINI(cIniFile & IniFile)
+{
+	m_Server = IniFile.GetValueSet("Authentication", "Server", DEFAULT_AUTH_SERVER);
+	m_Address = IniFile.GetValueSet("Authentication", "Address", DEFAULT_AUTH_ADDRESS);
+	m_ShouldAuthenticate = IniFile.GetValueSetB("Authentication", "Authenticate", true);
+}
+
+
+
+
+
+void cAuthenticator::Authenticate(int a_ClientID, const AString & a_UserName, const AString & a_ServerHash)
+{
+	if (!m_ShouldAuthenticate)
+	{
+		cRoot::Get()->AuthenticateUser(a_ClientID, a_UserName, Printf("%d", a_ClientID));
+		return;
+	}
+
+	cCSLock LOCK(m_CS);
+	m_Queue.push_back(cUser(a_ClientID, a_UserName, a_ServerHash));
+	m_QueueNonempty.Set();
+}
+
+
+
+
+
+void cAuthenticator::Start(cIniFile & IniFile)
+{
+	ReadINI(IniFile);
+	m_ShouldTerminate = false;
+	super::Start();
+}
+
+
+
+
+
+void cAuthenticator::Stop(void)
+{
+	m_ShouldTerminate = true;
+	m_QueueNonempty.Set();
+	Wait();
+}
+
+
+
+
+
+void cAuthenticator::Execute(void)
+{
+	for (;;)
+	{
+		cCSLock Lock(m_CS);
+		while (!m_ShouldTerminate && (m_Queue.size() == 0))
+		{
+			cCSUnlock Unlock(Lock);
+			m_QueueNonempty.Wait();
+		}
+		if (m_ShouldTerminate)
+		{
+			return;
+		}
+		ASSERT(!m_Queue.empty());
+
+		int ClientID = m_Queue.front().m_ClientID;
+		AString UserName = m_Queue.front().m_Name;
+		AString ServerID = m_Queue.front().m_ServerID;
+		m_Queue.pop_front();
+		Lock.Unlock();
+
+		AString NewUserName = UserName;
+		AString UUID;
+		if (AuthWithYggdrasil(NewUserName, ServerID, UUID))
+		{
+			LOGINFO("User %s authenticated with UUID '%s'", NewUserName.c_str(), UUID.c_str());
+			cRoot::Get()->AuthenticateUser(ClientID, NewUserName, UUID);
+		}
+		else
+		{
+			cRoot::Get()->KickUser(ClientID, "Failed to authenticate account!");
+		}
+	}  // for (-ever)
+}
+
+
+
+
+
+bool cAuthenticator::AuthWithYggdrasil(AString & a_UserName, const AString & a_ServerId, AString & a_UUID)
+{
+	AString REQUEST;
+	int ret, len, server_fd = -1;
+	unsigned char buf[1024];
+	const char *pers = "cAuthenticator";
+
+	entropy_context entropy;
+	ctr_drbg_context ctr_drbg;
+	ssl_context ssl;
+	x509_crt cacert;
+
+	/* Initialize the RNG and the session data */
+	memset(&ssl, 0, sizeof(ssl_context));
+	x509_crt_init(&cacert);
+
+	entropy_init(&entropy);
+	if ((ret = ctr_drbg_init(&ctr_drbg, entropy_func, &entropy, (const unsigned char *)pers, strlen(pers))) != 0)
+	{
+		LOGERROR("cAuthenticator: ctr_drbg_init returned %d", ret);
+		return false;
+	}
+
+	/* Initialize certificates */
+
+#if defined(POLARSSL_CERTS_C)
+	ret = x509_crt_parse(&cacert, (const unsigned char *)test_ca_list, strlen(test_ca_list));
+#else
+	ret = 1;
+	LOGWARNING("cAuthenticator: POLARSSL_CERTS_C is not defined.");
+#endif
+
+	if (ret < 0)
+	{
+		LOGERROR("cAuthenticator: x509_crt_parse returned -0x%x", -ret);
+		return false;
+	}
+
+	/* Connect */
+	if ((ret = net_connect(&server_fd, m_Server.c_str(), 443)) != 0)
+	{
+		LOGERROR("cAuthenticator: Can't connect to %s: %d", m_Server.c_str(), ret);
+		return false;
+	}
+
+	/* Setup */
+	if ((ret = ssl_init(&ssl)) != 0)
+	{
+		LOGERROR("cAuthenticator: ssl_init returned %d", ret);
+		return false;
+	}
+	ssl_set_endpoint(&ssl, SSL_IS_CLIENT);
+	ssl_set_authmode(&ssl, SSL_VERIFY_OPTIONAL);
+	ssl_set_ca_chain(&ssl, &cacert, NULL, "PolarSSL Server 1");
+	ssl_set_rng(&ssl, ctr_drbg_random, &ctr_drbg);
+	ssl_set_bio(&ssl, net_recv, &server_fd, net_send, &server_fd);
+
+	/* Handshake */
+	while ((ret = ssl_handshake(&ssl)) != 0)
+	{
+		if (ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE)
+		{
+			LOGERROR("cAuthenticator: ssl_handshake returned -0x%x", -ret);
+			return false;
+		}
+	}
+
+	/* Write the GET request */
+	AString ActualAddress = m_Address;
+	ReplaceString(ActualAddress, "%USERNAME%", a_UserName);
+	ReplaceString(ActualAddress, "%SERVERID%", a_ServerId);
+
+	REQUEST += "GET " + ActualAddress + " HTTP/1.1\r\n";
+	REQUEST += "Host: " + m_Server + "\r\n";
+	REQUEST += "User-Agent: MCServer\r\n";
+	REQUEST += "Connection: close\r\n";
+	REQUEST += "\r\n";
+
+	len = sprintf_s((char *)buf, sizeof(buf), REQUEST.c_str());
+
+	while ((ret = ssl_write(&ssl, buf, len)) <= 0)
+	{
+		if (ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE)
+		{
+			LOGERROR("cAuthenticator: ssl_write returned %d", ret);
+			return false;
+		}
+	}
+
+	/* Read the HTTP response */
+	std::string Builder;
+	for (;;)
+	{
+		len = sizeof(buf)-1;
+		memset(buf, 0, sizeof(buf));
+		ret = ssl_read(&ssl, buf, len);
+		if (ret > 0)
+		{
+			buf[ret] = '\0';
+		}
+
+		if (ret == POLARSSL_ERR_NET_WANT_READ || ret == POLARSSL_ERR_NET_WANT_WRITE)
+			continue;
+		if (ret == POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY)
+			break;
+		if (ret < 0)
+		{
+			LOGERROR("cAuthenticator: ssl_read returned %d", ret);
+			break;
+		}
+		if (ret == 0)
+		{
+			LOGERROR("cAuthenticator: EOF");
+			break;
+		}
+
+		std::string str;
+		str.append(reinterpret_cast<const char*>(buf));
+		Builder += str;
+	} 
+
+	ssl_close_notify(&ssl);
+	x509_crt_free(&cacert);
+	net_close(server_fd);
+	ssl_free(&ssl);
+	entropy_free(&entropy);
+	memset(&ssl, 0, sizeof(ssl));
+
+	std::string prefix("HTTP/1.1 200 OK");
+	if (Builder.compare(0, prefix.size(), prefix))
+		return false;
+
+	std::stringstream ResponseBuilder;
+	bool NewLine = false;
+	bool IsNewLine = false;
+	for (std::string::const_iterator i = Builder.begin(); i <= Builder.end(); ++i)
+	{
+		if (NewLine)
+		{
+			ResponseBuilder << *i;
+		}
+		else if (!NewLine && *i == '\n')
+		{
+			if (IsNewLine)
+			{
+				NewLine = true;
+			}
+			else
+			{
+				IsNewLine = true;
+			}
+		}
+		else if (*i != '\r')
+		{
+			IsNewLine = false;
+		}
+	}
+
+	AString RESPONSE = ResponseBuilder.str();
+
+	if (RESPONSE.empty())
+		return false;
+
+	Json::Value root;
+	Json::Reader reader;
+	if (!reader.parse(RESPONSE, root, false))
+	{
+		LOGWARNING("cAuthenticator: Cannot parse Received Data to json!");
+		return false;
+	}
+
+	a_UserName = root.get("name", "Unknown").asString();
+	a_UUID = root.get("id", "").asString();
+	return true;
+}
+
+
+
+
+
diff --git a/src/Protocol/Authenticator.h b/src/Protocol/Authenticator.h
new file mode 100644
index 000000000..211f51394
--- /dev/null
+++ b/src/Protocol/Authenticator.h
@@ -0,0 +1,93 @@
+
+// cAuthenticator.h
+
+// Interfaces to the cAuthenticator class representing the thread that authenticates users against the official MC server
+// Authentication prevents "hackers" from joining with an arbitrary username (possibly impersonating the server admins)
+// For more info, see http://wiki.vg/Session#Server_operation
+// In MCS, authentication is implemented as a single thread that receives queued auth requests and dispatches them one by one.
+
+
+
+
+
+#pragma once
+#ifndef CAUTHENTICATOR_H_INCLUDED
+#define CAUTHENTICATOR_H_INCLUDED
+
+#include "../OSSupport/IsThread.h"
+
+
+
+
+
+// fwd: "cRoot.h"
+class cRoot;
+
+
+
+
+
+class cAuthenticator :
+	public cIsThread
+{
+	typedef cIsThread super;
+
+public:
+	cAuthenticator(void);
+	~cAuthenticator();
+
+	/** (Re-)read server and address from INI: */
+	void ReadINI(cIniFile & IniFile);
+
+	/** Queues a request for authenticating a user. If the auth fails, the user will be kicked */
+	void Authenticate(int a_ClientID, const AString & a_UserName, const AString & a_ServerHash);
+
+	/** Starts the authenticator thread. The thread may be started and stopped repeatedly */
+	void Start(cIniFile & IniFile);
+
+	/** Stops the authenticator thread. The thread may be started and stopped repeatedly */
+	void Stop(void);
+
+private:
+
+	class cUser
+	{
+	public:
+		int     m_ClientID;
+		AString m_Name;
+		AString m_ServerID;
+
+		cUser(int a_ClientID, const AString & a_Name, const AString & a_ServerID) :
+			m_ClientID(a_ClientID),
+			m_Name(a_Name),
+			m_ServerID(a_ServerID)
+		{
+		}
+	};
+
+	typedef std::deque<cUser> cUserList;
+
+	cCriticalSection m_CS;
+	cUserList        m_Queue;
+	cEvent           m_QueueNonempty;
+
+	AString m_Server;
+	AString m_Address;
+	bool    m_ShouldAuthenticate;
+
+	/** cIsThread override: */
+	virtual void Execute(void) override;
+
+	/** Returns true if the user authenticated okay, false on error; iLevel is the recursion deptht (bails out if too deep) */
+	bool AuthWithYggdrasil(AString & a_UserName, const AString & a_ServerId, AString & a_UUID);
+};
+
+
+
+
+
+#endif  // CAUTHENTICATOR_H_INCLUDED
+
+
+
+