andre@908: /* Copyright (C) 2014 by Bundesamt für Sicherheit in der Informationstechnik
andre@908:  * Software engineering by Intevation GmbH
andre@908:  *
andre@908:  * This file is Free Software under the GNU GPL (v>=2)
andre@908:  * and comes with ABSOLUTELY NO WARRANTY!
andre@908:  * See LICENSE.txt for details.
andre@908:  */
andre@908: /* TODO: Wrap ssl_session in a class for reuse.
andre@908:  * see programs/ssl/ssl_client2.c for example of session reuse */
andre@908: #include "sslconnection_bare.h"
andre@908: #include "sslhelp.h"
andre@908: 
andre@908: #include <QFile>
andre@910: #include <QSaveFile>
andre@908: #include <QUuid>
andre@908: #include <QApplication>
andre@908: 
andre@908: #define MAX_IO_TRIES 10
andre@908: #define MAX_RESETS 10
andre@908: 
andre@908: #ifdef CONNECTION_DEBUG
andre@908: static void my_debug(void *ctx, int level, const char *str)
andre@908: {
andre@908:     fprintf((FILE *) ctx, "%s", str);
andre@908:     fflush((FILE *) ctx);
andre@908: }
andre@908: #endif
andre@908: 
andre@908: SSLConnectionBare::SSLConnectionBare(const QString& url,
andre@908:                              const QByteArray& certificate):
andre@908:     SSLConnection (url, certificate)
andre@908: {
andre@908:     int ret = -1;
andre@908: 
andre@908:     memset(&mSSL, 0, sizeof(ssl_context));
andre@908:     memset(&mSavedSession, 0, sizeof( ssl_session ) );
andre@908: 
andre@908:     ret = init();
andre@908:     if (ret == 0) {
andre@908:         mInitialized = true;
andre@908:     } else {
andre@908:         qDebug() << "Initialization error: " + getPolarSSLErrorMsg(ret);
andre@908:     }
andre@908: }
andre@908: 
andre@908: int SSLConnectionBare::init()
andre@908: {
andre@908:     int ret = -1;
andre@908:     QUuid uuid = QUuid::createUuid();
andre@908:     QString personalString = QApplication::applicationName() + uuid.toString();
andre@908:     QByteArray personalBa = personalString.toLocal8Bit();
andre@908: 
andre@908:     x509_crt_init(&mX509PinnedCert);
andre@908:     entropy_init(&mEntropy);
andre@908: 
andre@908:     ret = ssl_init(&mSSL);
andre@908:     if (ret != 0) {
andre@908:         /* The only documented error is malloc failed */
andre@908:         mErrorState = ErrUnknown;
andre@908:         return ret;
andre@908:     }
andre@908: 
andre@908:     /*
andre@908:      * Initialize random generator.
andre@908:      * Personalisation string, does not need to be random but
andre@908:      * should be unique according to documentation.
andre@908:      *
andre@908:      * the ctr_drbg structure does not need to be freed explicitly.
andre@908:      */
andre@908:     ret = ctr_drbg_init(&mCtr_drbg, entropy_func, &mEntropy,
andre@908:                         (const unsigned char*) personalBa.constData(),
andre@908:                         personalBa.size());
andre@908:     if (ret != 0) {
andre@908:         ssl_free(&mSSL);
andre@908:         mErrorState = ErrUnknown;
andre@908:         return ret;
andre@908:     }
andre@908: 
andre@908:     ret = x509_crt_parse(&mX509PinnedCert,
andre@908:                          (const unsigned char*) mPinnedCert.constData(),
andre@908:                          mPinnedCert.size());
andre@908:     if (ret != 0){
andre@908:         ssl_free(&mSSL);
andre@908:         mErrorState = InvalidPinnedCertificate;
andre@908:         return ret;
andre@908:     }
andre@908: 
andre@908:     ssl_set_endpoint(&mSSL, SSL_IS_CLIENT);
andre@908:     ssl_set_authmode(&mSSL, SSL_VERIFY_OPTIONAL);
andre@908:     ssl_set_ca_chain(&mSSL, &mX509PinnedCert, NULL, NULL);
andre@908:     ssl_set_renegotiation(&mSSL, SSL_RENEGOTIATION_DISABLED);
andre@908:     ssl_set_rng(&mSSL, ctr_drbg_random, &mCtr_drbg);
andre@908: #ifdef RELEASE_BUILD
andre@908:     ssl_set_min_version(&mSSL, SSL_MAJOR_VERSION_3, SSL_MINOR_VERSION_3);
andre@908: #endif
andre@908: 
andre@908: #ifdef CONNECTION_DEBUG
andre@908:     ssl_set_dbg(&mSSL, my_debug, stdout);
andre@908: #endif
andre@908: 
andre@908:     return 0;
andre@908: }
andre@908: 
andre@908: SSLConnectionBare::~SSLConnectionBare() {
andre@908:     disconnect();
andre@908:     x509_crt_free(&mX509PinnedCert);
andre@908:     entropy_free(&mEntropy);
andre@908:     if (mInitialized) {
andre@908:         ssl_free(&mSSL);
andre@908:     }
andre@908: }
andre@908: 
andre@908: void SSLConnectionBare::disconnect() {
andre@908:     if (mConnected) {
andre@908:         ssl_close_notify(&mSSL);
andre@908:         if (mServerFD != -1) {
andre@908:             net_close(mServerFD);
andre@908:             mServerFD = -1;
andre@908:         }
andre@908:         ssl_session_free(&mSavedSession);
andre@908:         mConnected = false;
andre@908:     }
andre@908: }
andre@908: 
andre@908: int SSLConnectionBare::connect() {
andre@908:     int ret = -1;
andre@908: 
andre@908:     if (!mInitialized) {
andre@908:         mErrorState = ErrUnknown;
andre@908:         return -1;
andre@908:     }
andre@908: 
andre@908:     ret = net_connect(&mServerFD, mUrl.host().toLatin1().constData(),
andre@908:                   mUrl.port(443));
andre@908: 
andre@908:     if (ret != 0) {
andre@908:         qDebug() << "Connect failed: " << getPolarSSLErrorMsg(ret);
andre@908:         mErrorState = NoConnection;
andre@908:         return ret;
andre@908:     }
andre@908: 
andre@908:     ssl_set_bio(&mSSL, net_recv, &mServerFD,
andre@908:                        net_send, &mServerFD);
andre@908: 
andre@908:     while ((ret = ssl_handshake(&mSSL)) != 0) {
andre@908:         if (ret != POLARSSL_ERR_NET_WANT_READ &&
andre@908:                 ret != POLARSSL_ERR_NET_WANT_WRITE) {
andre@908:             qDebug() << "SSL Handshake failed: " << getPolarSSLErrorMsg(ret);
andre@908:             mErrorState = SSLHandshakeFailed;
andre@908:             return ret;
andre@908:         }
andre@908:     }
andre@908: 
andre@908:     ret = ssl_get_session(&mSSL, &mSavedSession);
andre@908:     if (ret != 0) {
andre@908:         qDebug() << "SSL get session failed: " << getPolarSSLErrorMsg(ret);
andre@908: 
andre@908:         mErrorState = NoConnection;
andre@908:         return ret;
andre@908:     }
andre@908:     printf( " ok\n    [ Ciphersuite is %s ]\n",
andre@908:             ssl_get_ciphersuite( &mSSL) );
andre@908:     ret = validateCertificate();
andre@908: 
andre@908:     if (ret == 0) {
andre@908:         mConnected = true;
andre@908:     }
andre@908:     return ret;
andre@908: }
andre@908: 
andre@908: int SSLConnectionBare::validateCertificate()
andre@908: {
andre@908:     int ret = -1;
andre@908:     const x509_crt *peerCert = NULL;
andre@908: 
andre@908:     /* we might want to set the verify function
andre@908:      * with ssl_set_verify before to archive the
andre@908:      * certificate pinning. */
andre@908: 
andre@908:     ret = ssl_get_verify_result(&mSSL);
andre@908: 
andre@908:     if (ret != 0 ) {
andre@908:         if((ret & BADCERT_EXPIRED) != 0)
andre@908:            qDebug() << "server certificate has expired";
andre@908:         if((ret & BADCERT_REVOKED) != 0)
andre@908:            qDebug() << "server certificate has been revoked";
andre@908:         if((ret & BADCERT_CN_MISMATCH) != 0)
andre@908:            qDebug() << "CN mismatch";
andre@908:         if((ret & BADCERT_NOT_TRUSTED) != 0)
andre@908:             qDebug() << "self-signed or not signed by a trusted CA";
andre@908:         ret = -1;
andre@908: #ifdef RELEASE_BUILD
andre@908:         mErrorState = InvalidCertificate;
andre@908:         return -1;
andre@908: #endif
andre@908:     }
andre@908: 
andre@908:     peerCert = ssl_get_peer_cert(&mSSL);
andre@908: 
andre@908:     if (!peerCert) {
andre@908:         mErrorState = InvalidCertificate;
andre@908:         qDebug() << "Failed to get peer cert";
andre@908:         return -1;
andre@908:     }
andre@908: 
andre@908:     if (peerCert->raw.len == 0 ||
andre@908:         peerCert->raw.len != mX509PinnedCert.raw.len) {
andre@908:         mErrorState = InvalidCertificate;
andre@908:         qDebug() << "Certificate length mismatch";
andre@908:         return -1;
andre@908:     }
andre@908: 
andre@908:     /* You can never be sure what those c++ operators do..
andre@908:     if (mPinnedCert != QByteArray::fromRawData(
andre@908:                 (const char*) peerCert->raw.p,
andre@908:             peerCert->raw.len)) {
andre@908:         qDebug() << "Certificate content mismatch";
andre@908:     }
andre@908:     */
andre@908: 
andre@908:     for (unsigned int i = 0; i < peerCert->raw.len; i++) {
andre@908:         if (peerCert->raw.p[i] != mX509PinnedCert.raw.p[i]) {
andre@908:             qDebug() << "Certificate content mismatch";
andre@908:             mErrorState = InvalidCertificate;
andre@908:             return -1;
andre@908:         }
andre@908:     }
andre@908:     return 0;
andre@908: }
andre@908: 
andre@908: int SSLConnectionBare::write (const QByteArray& request)
andre@908: {
andre@908:     unsigned int tries = 0;
andre@908:     int ret = -1;
andre@908: 
andre@908:     const unsigned char *buf = (const unsigned char *) request.constData();
andre@908:     size_t len = (size_t) request.size();
andre@908: 
andre@908:     if (mNeedsReset) {
andre@908:         ret = reset();
andre@908:         if (ret != 0) {
andre@908:             qDebug() << "Reset failed: " << getPolarSSLErrorMsg(ret);
andre@908:             return ret;
andre@908:         }
andre@908:     }
andre@908: 
andre@908:     qDebug() << "Sending request: " << request;
andre@908:     /* According to doc for ssl_write:
andre@908:      *
andre@908:      * When this function returns POLARSSL_ERR_NET_WANT_WRITE,
andre@908:      * it must be called later with the same arguments,
andre@908:      * until it returns a positive value.
andre@908:      */
andre@908:     do {
andre@908:         ret = ssl_write(&mSSL, buf, len);
andre@908:         if (ret >= 0) {
andre@908:             if ((unsigned int) ret == len) {
andre@908:                 return 0;
andre@908:             } else {
andre@908:                 qDebug() << "Write failed to write everything";
andre@908:                 return -1;
andre@908:             }
andre@908:         }
andre@908:         if (ret != POLARSSL_ERR_NET_WANT_WRITE &&
andre@908:                 ret != POLARSSL_ERR_NET_WANT_READ) {
andre@908:             return ret;
andre@908:         }
andre@908:         tries++;
andre@908:         net_usleep(100000); /* sleep 100ms to give the socket a chance
andre@908:                                to clean up. */
andre@908:     } while (tries < MAX_IO_TRIES);
andre@908: 
andre@908:     return ret;
andre@908: }
andre@908: 
andre@908: 
andre@908: int SSLConnectionBare::reset()
andre@908: {
andre@908:     int ret = -1;
andre@908:     ssl_close_notify(&mSSL);
andre@908: 
andre@908:     ret = ssl_session_reset(&mSSL);
andre@908:     if (ret != 0)
andre@908:     {
andre@908:         qDebug() << "SSL Connection reset failed: "
andre@908:                  << getPolarSSLErrorMsg(ret);
andre@908:         return ret;
andre@908:     }
andre@908: 
andre@908:     ssl_set_session(&mSSL, &mSavedSession);
andre@908: 
andre@908:     ret = net_connect(&mServerFD, mUrl.host().toLatin1().constData(),
andre@908:                   mUrl.port(443));
andre@908: 
andre@908:     if (ret != 0) {
andre@908:         mErrorState = NoConnection;
andre@908:         qDebug() << "Connection failed." << getPolarSSLErrorMsg(ret);
andre@908:         return ret;
andre@908:     }
andre@908: 
andre@908:     while ((ret = ssl_handshake(&mSSL)) != 0) {
andre@908:         if (ret != POLARSSL_ERR_NET_WANT_READ &&
andre@908:                 ret != POLARSSL_ERR_NET_WANT_WRITE) {
andre@908:             qDebug() << "SSL Handshake failed: "
andre@908:                  << getPolarSSLErrorMsg(ret);
andre@908:             mErrorState = SSLHandshakeFailed;
andre@908:             return ret;
andre@908:         }
andre@908:     }
andre@908: 
andre@908:     qDebug() << "Reset connection. ";
andre@908:     /* Validation should not be necessary as we reused a saved
andre@908:      * session. But just to be sure. */
andre@908:     return validateCertificate();
andre@908: }
andre@908: 
andre@908: QByteArray SSLConnectionBare::read(size_t len)
andre@908: {
andre@908:     unsigned char buf[len];
andre@908:     QByteArray retval("");
andre@908:     int ret = -1;
andre@908:     unsigned int tries = 0;
andre@908: 
andre@908:     mNeedsReset = true;
andre@908:     do {
andre@908:         memset (buf, 0, sizeof(buf));
andre@908:         ret = ssl_read(&mSSL, buf, len);
andre@908:         if (ret == 0 ||
andre@908:             ret == POLARSSL_ERR_SSL_CONN_EOF ||
andre@908:             ret == POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY) {
andre@908:             /* EOF */
andre@908:             return retval;
andre@908:         }
andre@908:         if (ret == POLARSSL_ERR_NET_WANT_WRITE ||
andre@908:                 ret == POLARSSL_ERR_NET_WANT_READ) {
andre@908:             net_usleep(100000); /* sleep 100ms to give the socket a chance
andre@908:                                    to recover */
andre@908:             tries++;
andre@908:         }
andre@908:         if (ret <= 0) {
andre@908:             qDebug() << "Read failed: " << getPolarSSLErrorMsg(ret);
andre@908:             return QByteArray();
andre@908:         }
andre@908:         if (len < (len - (unsigned int) ret)) {
andre@908:             /* Should never happen if ssl_read behaves */
andre@908:             qDebug() << "integer overflow in polarSSLRead";
andre@908:             return QByteArray();
andre@908:         }
andre@908:         len -= (unsigned int) ret;
andre@908:         retval.append((const char *)buf, ret);
andre@908:     } while (len > 0 && tries < MAX_IO_TRIES);
andre@908: 
andre@908:     return retval;
andre@908: }
andre@908: 
andre@910: QMap<QString, QString> SSLConnectionBare::parseHeaders(QByteArray *data)
andre@910: {
andre@910:     int bodyStart = data->indexOf("\r\n\r\n");
andre@910:     QMap<QString, QString> retval;
andre@910:     QByteArray headers;
andre@910:     QString response(*data);
andre@910:     if (bodyStart == -1) {
andre@910:         qDebug() << "Could not find header end.";
andre@910:         return retval;
andre@910:     }
andre@908: 
andre@910:     /* Take the headers with one additional line break */
andre@910:     headers = data->left(bodyStart + 2);
andre@910:     /* Chop off the head */
andre@910: 
andre@910:     foreach (const QString& line, response.split("\r\n")) {
andre@910:         int sepPos = -1;
andre@910:         sepPos = line.indexOf(": ");
andre@910:         if (sepPos == -1) {
andre@910:             continue;
andre@910:         }
andre@910:         QString key = line.left(sepPos);
andre@910:         QString value = line.right(line.size() - sepPos - 2);
andre@910: 
andre@910:         retval.insert(key, value);
andre@910:     }
andre@910: 
andre@910:     *data = data->right(data->size() - bodyStart - 4);
andre@910:     return retval;
andre@910: }
andre@910: 
andre@910: QDateTime SSLConnectionBare::getLastModifiedHeader(const QString &resource) {
andre@910:     int ret = -1;
andre@910:     QByteArray response;
andre@910:     QLocale cLocale = QLocale::c();
andre@910:     QMap<QString, QString> headers;
andre@910:     QString headRequest =
andre@910:         QString::fromLatin1("HEAD %1 HTTP/1.0\r\n\r\n").arg(resource);
andre@910: 
andre@910:     ret = write(headRequest.toUtf8());
andre@910:     if (ret != 0) {
andre@910:         return QDateTime();
andre@910:     }
andre@910: 
andre@910:     response = read(1024);
andre@910: 
andre@910:     qDebug() << "Response from server was: " << response;
andre@910: 
andre@910:     if (response.isNull()) {
andre@910:         qDebug() << "No response";
andre@910:         return QDateTime();
andre@910:     }
andre@910: 
andre@910:     headers = parseHeaders(&response);
andre@910:     const QString lastModified = headers.value("Last-Modified");
andre@910:     if (!lastModified.isEmpty()) {
andre@910:         QDateTime candidate = cLocale.toDateTime(lastModified,
andre@910:                 "ddd, dd MMM yyyy HH:mm:ss' GMT'");
andre@910:         if (candidate.isValid()) {
andre@910:             return candidate;
andre@910:         }
andre@910:     }
andre@910:     return QDateTime();
andre@910: }
andre@910: 
andre@910: bool SSLConnectionBare::downloadFile(const QString &resource,
andre@910:                               const QString &fileName,
andre@910:                               size_t maxSize)
andre@910: {
andre@910:     int ret = -1;
andre@910:     size_t bytesRead = 0;
andre@910:     QString getRequest =
andre@910:         QString::fromLatin1("GET %1 HTTP/1.0\r\n\r\n").arg(resource);
andre@910: 
andre@910:     QSaveFile outputFile(fileName);
andre@910: 
andre@910:     ret = write(getRequest.toUtf8());
andre@910: 
andre@913:     if (ret != 0) {
andre@913:         qDebug() << "Failed to send request.";
andre@913:         return false;
andre@913:     }
andre@913: 
andre@910:     // Open / Create the file to write to.
andre@910:     if (!outputFile.open(QIODevice::WriteOnly)) {
andre@910:         qDebug() << "Failed to open file";
andre@910:         return false;
andre@910:     }
andre@910: 
andre@910:     bool inBody = false;
andre@910:     QMap <QString, QString> headers;
andre@910:     do {
andre@910:         /* Read the response in 8KiB chunks */
andre@910:         int responseSize = 0;
andre@910:         QByteArray response = read(8192);
andre@910:         if (response.isNull()) {
andre@910:             qDebug() << "Error reading response";
andre@910:             return false;
andre@910:         }
andre@910:         responseSize = response.size();
andre@910:         if (!inBody) {
andre@910:             headers = parseHeaders(&response);
andre@910:             inBody = true;
andre@910:         }
andre@910:         outputFile.write(response);
andre@910:         bytesRead += responseSize;
andre@910:         if (responseSize < 8192) {
andre@910:             /* Nothing more to read */
andre@910:             break;
andre@910:         }
andre@910:     } while (bytesRead < maxSize);
andre@910: 
andre@910:     return outputFile.commit();
andre@910: }
andre@910: 
andre@990: void SSLConnectionBare::setCiphersuites(int ciphers[]) {
andre@990:     if (mInitialized) {
andre@990:         ssl_set_ciphersuites(&mSSL, ciphers);
andre@990:     }
andre@990: }