Added support for determining SmartCard Reader associated with a certificate (if any)

This patch implements monitoring for SmartCard ejection. This is done by periodically (currently every second) polling smart card reader for the smart card status. If the smart card status becomes "absent" or "unknown" (an error to query the smartcard), the TLS session is aborted. This usually results in an attempt to reestablish TLS which will pop up "please insert the smart card" dialog. License: This patch is BSD-licensed, see Documentation/Licenses/BSD-simplified.txt for details.
author: Alexey Melnikov <alexey.melnikov@isode.com> 2012-03-09 20:19:19 (GMT)
committer: Kevin Smith <git@kismith.co.uk> 2012-04-11 10:25:16 (GMT)
commit: d5f885dd9aa65d18145a99826a1c30aeb62aca8e (patch)
tree: bef9f1478f3dcc602d3aa8595ab27eb7356d4da8 /Swiften
parent: 1e61cace31a3395f5470a03c3bcf2b7f32d79d03 (diff)
download: swift-d5f885dd9aa65d18145a99826a1c30aeb62aca8e.zip
swift-d5f885dd9aa65d18145a99826a1c30aeb62aca8e.tar.bz2
4 files changed, 227 insertions, 6 deletions
diff --git a/Swiften/TLS/CAPICertificate.cpp b/Swiften/TLS/CAPICertificate.cpp
index 0dc3009..b33ebcf 100644
--- a/Swiften/TLS/CAPICertificate.cpp
+++ b/Swiften/TLS/CAPICertificate.cpp
@@ -5,9 +5,11 @@
  */
 #pragma once
 
+#include <Swiften/Network/TimerFactory.h>
 #include <Swiften/TLS/CAPICertificate.h>
 #include <Swiften/StringCodecs/Hexify.h>
 
+#include <boost/bind.hpp>
 #include <boost/algorithm/string/predicate.hpp>
 
 // Size of the SHA1 hash
@@ -15,15 +17,39 @@
 
 
 namespace Swift {
-CAPICertificate::CAPICertificate(const std::string& capiUri)
-			  		 : valid_(false), uri_(capiUri), certStoreHandle_(0), certStore_(), certName_() {
+
+CAPICertificate::CAPICertificate(const std::string& capiUri, TimerFactory* timerFactory)
+	: valid_(false),
+	uri_(capiUri),
+	certStoreHandle_(0),
+	scardContext_(0),
+	cardHandle_(0),
+	certStore_(),
+	certName_(),
+	smartCardReaderName_(),
+	timerFactory_(timerFactory) {
+
 	setUri(capiUri);
 }
 
 CAPICertificate::~CAPICertificate() {
+	if (smartCardTimer_) {
+		smartCardTimer_->stop();
+		smartCardTimer_->onTick.disconnect(boost::bind(&CAPICertificate::handleSmartCardTimerTick, this));
+		smartCardTimer_.reset();
+	}
+
 	if (certStoreHandle_) {
 		CertCloseStore(certStoreHandle_, 0);
 	}
+
+	if (cardHandle_) {
+		(void) SCardDisconnect(cardHandle_, SCARD_LEAVE_CARD);
+	}
+
+	if (scardContext_) {
+		SCardReleaseContext(scardContext_);
+	}
 }
 
 bool CAPICertificate::isNull() const {
@@ -38,6 +64,10 @@ const std::string& CAPICertificate::getCertName() const {
 	return certName_;
 }
 
+const std::string& CAPICertificate::getSmartCardReaderName() const {
+	return smartCardReaderName_;
+}
+
 PCCERT_CONTEXT findCertificateInStore (HCERTSTORE certStoreHandle, const std::string &certName) {
 	PCCERT_CONTEXT pCertContext = NULL;
 
@@ -170,6 +200,30 @@ void CAPICertificate::setUri (const std::string& capiUri) {
 		return;
 	}
 
+
+	char smartcard_reader[1024];
+	DWORD buflen;
+
+	buflen = sizeof(smartcard_reader);
+	if (!CryptGetProvParam(hprov, PP_SMARTCARD_READER, (BYTE *)&smartcard_reader, &buflen, 0)) {
+		DWORD error;
+
+		error = GetLastError();
+		smartCardReaderName_ = "";
+	} else {
+		LONG       lRet;
+
+		smartCardReaderName_ = smartcard_reader;
+
+		lRet = SCardEstablishContext(SCARD_SCOPE_USER, NULL, NULL, &scardContext_);
+		if (SCARD_S_SUCCESS == lRet) {
+			// Initiate monitoring for smartcard ejection
+			smartCardTimer_ = timerFactory_->createTimer(SMARTCARD_EJECTION_CHECK_FREQ);
+		} else {
+			///Need to handle an error here
+		}
+	}
+
 	if (!CryptGetUserKey(hprov, pinfo->dwKeySpec, &key)) {
 		CryptReleaseContext(hprov, 0);
 		free(pinfo);
@@ -180,7 +234,133 @@ void CAPICertificate::setUri (const std::string& capiUri) {
 	CryptReleaseContext(hprov, 0);
 	free(pinfo);
 
+	if (smartCardTimer_) {
+		smartCardTimer_->onTick.connect(boost::bind(&CAPICertificate::handleSmartCardTimerTick, this));
+		smartCardTimer_->start();
+	}
+
 	valid_ = true;
 }
 
+static void smartcard_check_status (SCARDCONTEXT  hContext,
+				    const char * pReader,
+				    SCARDHANDLE hCardHandle,     // Can be 0 on the first call
+				    SCARDHANDLE * newCardHandle, // The handle returned
+				    DWORD * pdwState) {
+	LONG            lReturn;
+	DWORD           dwAP;
+	char            szReader[200];
+	DWORD           cch = sizeof(szReader);
+	BYTE            bAttr[32];
+	DWORD           cByte = 32;
+
+	if (hCardHandle == 0) {
+		lReturn = SCardConnect(hContext,
+					pReader,
+					SCARD_SHARE_SHARED,
+					SCARD_PROTOCOL_T0 | SCARD_PROTOCOL_T1,
+					&hCardHandle,
+					&dwAP);
+		if ( SCARD_S_SUCCESS != lReturn ) {
+			hCardHandle = 0;
+			if (SCARD_E_NO_SMARTCARD == lReturn || SCARD_W_REMOVED_CARD == lReturn) {
+				*pdwState = SCARD_ABSENT;
+			} else {
+				*pdwState = SCARD_UNKNOWN;
+			}
+			goto done;
+		}
+	}
+
+	lReturn = SCardStatus(hCardHandle,
+				szReader,	// Unfortunately we can't use NULL here
+				&cch,
+				pdwState,
+				NULL,
+				(LPBYTE)&bAttr,
+				&cByte);
+
+	if ( SCARD_S_SUCCESS != lReturn ) {
+		if (SCARD_E_NO_SMARTCARD == lReturn || SCARD_W_REMOVED_CARD == lReturn) {
+			*pdwState = SCARD_ABSENT;
+		} else {
+			*pdwState = SCARD_UNKNOWN;
+		}
+	}
+
+done:
+	if (newCardHandle == NULL) {
+		(void) SCardDisconnect(hCardHandle, SCARD_LEAVE_CARD);
+		hCardHandle = 0;
+	} else {
+		*newCardHandle = hCardHandle;
+	}
+}
+
+bool CAPICertificate::checkIfSmartCardPresent () {
+
+	DWORD dwState;
+
+	if (!smartCardReaderName_.empty()) {
+		smartcard_check_status (scardContext_,
+					smartCardReaderName_.c_str(),
+					cardHandle_,
+					&cardHandle_,
+					&dwState);
+////DEBUG
+		switch ( dwState ) {
+		case SCARD_ABSENT:
+		    printf("Card absent.\n");
+		    break;
+		case SCARD_PRESENT:
+		    printf("Card present.\n");
+		    break;
+		case SCARD_SWALLOWED:
+		    printf("Card swallowed.\n");
+		    break;
+		case SCARD_POWERED:
+		    printf("Card has power.\n");
+		    break;
+		case SCARD_NEGOTIABLE:
+		    printf("Card reset and waiting PTS negotiation.\n");
+		    break;
+		case SCARD_SPECIFIC:
+		    printf("Card has specific communication protocols set.\n");
+		    break;
+		default:
+		    printf("Unknown or unexpected card state.\n");
+		    break;
+		}
+
+
+
+		switch ( dwState ) {
+		case SCARD_ABSENT:
+		    return false;
+
+		case SCARD_PRESENT:
+		case SCARD_SWALLOWED:
+		case SCARD_POWERED:
+		case SCARD_NEGOTIABLE:
+		case SCARD_SPECIFIC:
+		    return true;
+
+		default:
+		    return false;
+		}
+	} else {
+		return false;
+	}
+}
+
+void CAPICertificate::handleSmartCardTimerTick() {
+
+	if (checkIfSmartCardPresent() == false) {
+		smartCardTimer_->stop();
+		onCertificateCardRemoved();
+	} else {
+		smartCardTimer_->start();
+	}
+}
+
 }
diff --git a/Swiften/TLS/CAPICertificate.h b/Swiften/TLS/CAPICertificate.h
index 4204a6b..c8c00fe 100644
--- a/Swiften/TLS/CAPICertificate.h
+++ b/Swiften/TLS/CAPICertificate.h
@@ -6,17 +6,26 @@
 
 #pragma once
 
+#include <Swiften/Base/boost_bsignals.h>
 #include <Swiften/Base/SafeByteArray.h>
 #include <Swiften/TLS/CertificateWithKey.h>
+#include <Swiften/Network/Timer.h>
 
 #define SECURITY_WIN32
 #include <Windows.h>
 #include <WinCrypt.h>
+#include <Winscard.h>
+
+/* In ms */
+#define SMARTCARD_EJECTION_CHECK_FREQ	1000
 
 namespace Swift {
+	class TimerFactory;
+
 	class CAPICertificate : public Swift::CertificateWithKey {
 		public:
-			CAPICertificate(const std::string& capiUri);
+////Allow timerFactory to be NULL?
+			CAPICertificate(const std::string& capiUri, TimerFactory* timerFactory);
 
 			virtual ~CAPICertificate();
 
@@ -26,18 +35,32 @@ namespace Swift {
 
 			const std::string& getCertName() const;
 
+			const std::string& getSmartCardReaderName() const;
+
+		public:
+			boost::signal<void ()> onCertificateCardRemoved;
+
 		private:
 			void setUri (const std::string& capiUri);
 
+			void handleSmartCardTimerTick();
+
+			bool checkIfSmartCardPresent();
+
 		private:
 			bool valid_;
 			std::string uri_;
 
 			HCERTSTORE certStoreHandle_;
+			SCARDCONTEXT  scardContext_;
+			SCARDHANDLE   cardHandle_;
 
 			/* Parsed components of the uri_ */
 			std::string certStore_;
 			std::string certName_;
+			std::string smartCardReaderName_;
+			boost::shared_ptr<Timer> smartCardTimer_;
+			TimerFactory* timerFactory_;
 	};
 
 PCCERT_CONTEXT findCertificateInStore (HCERTSTORE certStoreHandle, const std::string &certName);
diff --git a/Swiften/TLS/Schannel/SchannelContext.cpp b/Swiften/TLS/Schannel/SchannelContext.cpp
index 4f8f36f..8e952ea 100644
--- a/Swiften/TLS/Schannel/SchannelContext.cpp
+++ b/Swiften/TLS/Schannel/SchannelContext.cpp
@@ -4,8 +4,10 @@
  * See Documentation/Licenses/BSD-simplified.txt for more information.
  */
 
-#include "Swiften/TLS/Schannel/SchannelContext.h"
-#include "Swiften/TLS/Schannel/SchannelCertificate.h"
+#include <boost/bind.hpp>
+
+#include <Swiften/TLS/Schannel/SchannelContext.h>
+#include <Swiften/TLS/Schannel/SchannelCertificate.h>
 #include <Swiften/TLS/CAPICertificate.h>
 #include <WinHTTP.h> // For SECURITY_FLAG_IGNORE_CERT_CN_INVALID
 
@@ -19,6 +21,7 @@ SchannelContext::SchannelContext()
 , m_my_cert_store(NULL)
 , m_cert_store_name("MY")
 , m_cert_name()
+, m_smartcard_reader()
 {
 	m_ctxtFlags = ISC_REQ_ALLOCATE_MEMORY | 
 				  ISC_REQ_CONFIDENTIALITY |
@@ -639,10 +642,21 @@ bool SchannelContext::setClientCertificate(CertificateWithKey::ref certificate)
 	// are valid at this point
 	m_cert_store_name = capiCertificate->getCertStoreName();
 	m_cert_name = capiCertificate->getCertName();
+////At the moment this is only useful for logging:
+	m_smartcard_reader = capiCertificate->getSmartCardReaderName();
+
+	capiCertificate->onCertificateCardRemoved.connect(boost::bind(&SchannelContext::handleCertificateCardRemoved, this));
+
 	return true;
 }
 
 //------------------------------------------------------------------------
+void SchannelContext::handleCertificateCardRemoved() {
+	//ToDo: Might want to log the reason ("certificate card ejected")
+	indicateError();
+}
+
+//------------------------------------------------------------------------
 
 Certificate::ref SchannelContext::getPeerCertificate() const 
 {
diff --git a/Swiften/TLS/Schannel/SchannelContext.h b/Swiften/TLS/Schannel/SchannelContext.h
index 70b0694..bce7415 100644
--- a/Swiften/TLS/Schannel/SchannelContext.h
+++ b/Swiften/TLS/Schannel/SchannelContext.h
@@ -10,7 +10,7 @@
 
 #include "Swiften/TLS/TLSContext.h"
 #include "Swiften/TLS/Schannel/SchannelUtil.h"
-#include <Swiften/TLS/CertificateWithKey.h>
+#include "Swiften/TLS/CertificateWithKey.h"
 #include "Swiften/Base/ByteArray.h"
 
 #define SECURITY_WIN32
@@ -62,6 +62,8 @@ namespace Swift
 		void			appendNewData(const SafeByteArray& data);
 		SECURITY_STATUS validateServerCertificate();
 
+		void			handleCertificateCardRemoved();
+
 	private:
 		enum SchannelState
 		{
@@ -86,5 +88,7 @@ namespace Swift
 		HCERTSTORE		m_my_cert_store;
 		std::string		m_cert_store_name;
 		std::string		m_cert_name;
+////Not needed, most likely
+		std::string		m_smartcard_reader;	//Can be empty string for non SmartCard certificates
 	};
 }
author	Alexey Melnikov <alexey.melnikov@isode.com>	2012-03-09 20:19:19 (GMT)
committer	Kevin Smith <git@kismith.co.uk>	2012-04-11 10:25:16 (GMT)
commit	d5f885dd9aa65d18145a99826a1c30aeb62aca8e (patch)
tree	bef9f1478f3dcc602d3aa8595ab27eb7356d4da8 /Swiften
parent	1e61cace31a3395f5470a03c3bcf2b7f32d79d03 (diff)
download	swift-d5f885dd9aa65d18145a99826a1c30aeb62aca8e.zip swift-d5f885dd9aa65d18145a99826a1c30aeb62aca8e.tar.bz2