--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/Orthanc/Core/HttpClient.cpp	Fri Oct 14 15:39:01 2016 +0200
@@ -0,0 +1,834 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders of this
+ * program give permission to link the code of its release with the
+ * OpenSSL project's "OpenSSL" library (or with modified versions of it
+ * that use the same license as the "OpenSSL" library), and distribute
+ * the linked executables. You must obey the GNU General Public License
+ * in all respects for all of the code used other than "OpenSSL". If you
+ * modify file(s) with this exception, you may extend this exception to
+ * your version of the file(s), but you are not obligated to do so. If
+ * you do not wish to do so, delete this exception statement from your
+ * version. If you delete this exception statement from all source files
+ * in the program, then also delete it here.
+ * 
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#include "PrecompiledHeaders.h"
+#include "HttpClient.h"
+
+#include "Toolbox.h"
+#include "OrthancException.h"
+#include "Logging.h"
+#include "ChunkedBuffer.h"
+
+#include <string.h>
+#include <curl/curl.h>
+#include <boost/algorithm/string/predicate.hpp>
+#include <boost/thread/mutex.hpp>
+
+
+#if ORTHANC_SSL_ENABLED == 1
+// For OpenSSL initialization and finalization
+#  include <openssl/conf.h>
+#  include <openssl/engine.h>
+#  include <openssl/err.h>
+#  include <openssl/evp.h>
+#  include <openssl/ssl.h>
+#endif
+
+
+#if ORTHANC_PKCS11_ENABLED == 1
+#  include "Pkcs11.h"
+#endif
+
+
+extern "C"
+{
+  static CURLcode GetHttpStatus(CURLcode code, CURL* curl, long* status)
+  {
+    if (code == CURLE_OK)
+    {
+      code = curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, status);
+      return code;
+    }
+    else
+    {
+      *status = 0;
+      return code;
+    }
+  }
+
+  // This is a dummy wrapper function to suppress any OpenSSL-related
+  // problem in valgrind. Inlining is prevented.
+#if defined(__GNUC__) || defined(__clang__)
+    __attribute__((noinline)) 
+#endif
+    static CURLcode OrthancHttpClientPerformSSL(CURL* curl, long* status)
+  {
+    return GetHttpStatus(curl_easy_perform(curl), curl, status);
+  }
+}
+
+
+
+namespace Orthanc
+{
+  class HttpClient::GlobalParameters
+  {
+  private:
+    boost::mutex    mutex_;
+    bool            httpsVerifyPeers_;
+    std::string     httpsCACertificates_;
+    std::string     proxy_;
+    long            timeout_;
+
+    GlobalParameters() : 
+      httpsVerifyPeers_(true),
+      timeout_(0)
+    {
+    }
+
+  public:
+    // Singleton pattern
+    static GlobalParameters& GetInstance()
+    {
+      static GlobalParameters parameters;
+      return parameters;
+    }
+
+    void ConfigureSsl(bool httpsVerifyPeers,
+                      const std::string& httpsCACertificates)
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+      httpsVerifyPeers_ = httpsVerifyPeers;
+      httpsCACertificates_ = httpsCACertificates;
+    }
+
+    void GetSslConfiguration(bool& httpsVerifyPeers,
+                             std::string& httpsCACertificates)
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+      httpsVerifyPeers = httpsVerifyPeers_;
+      httpsCACertificates = httpsCACertificates_;
+    }
+
+    void SetDefaultProxy(const std::string& proxy)
+    {
+      LOG(INFO) << "Setting the default proxy for HTTP client connections: " << proxy;
+
+      {
+        boost::mutex::scoped_lock lock(mutex_);
+        proxy_ = proxy;
+      }
+    }
+
+    void GetDefaultProxy(std::string& target)
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+      target = proxy_;
+    }
+
+    void SetDefaultTimeout(long seconds)
+    {
+      LOG(INFO) << "Setting the default timeout for HTTP client connections: " << seconds << " seconds";
+
+      {
+        boost::mutex::scoped_lock lock(mutex_);
+        timeout_ = seconds;
+      }
+    }
+
+    long GetDefaultTimeout()
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+      return timeout_;
+    }
+
+#if ORTHANC_PKCS11_ENABLED == 1
+    bool IsPkcs11Initialized()
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+      return Pkcs11::IsInitialized();
+    }
+
+    void InitializePkcs11(const std::string& module,
+                          const std::string& pin,
+                          bool verbose)
+    {
+      boost::mutex::scoped_lock lock(mutex_);
+      Pkcs11::Initialize(module, pin, verbose);
+    }
+#endif
+  };
+
+
+  struct HttpClient::PImpl
+  {
+    CURL* curl_;
+    struct curl_slist *defaultPostHeaders_;
+    struct curl_slist *userHeaders_;
+  };
+
+
+  static void ThrowException(HttpStatus status)
+  {
+    switch (status)
+    {
+      case HttpStatus_400_BadRequest:
+        throw OrthancException(ErrorCode_BadRequest);
+
+      case HttpStatus_401_Unauthorized:
+      case HttpStatus_403_Forbidden:
+        throw OrthancException(ErrorCode_Unauthorized);
+
+      case HttpStatus_404_NotFound:
+        throw OrthancException(ErrorCode_UnknownResource);
+
+      default:
+        throw OrthancException(ErrorCode_NetworkProtocol);
+    }
+  }
+
+
+  static CURLcode CheckCode(CURLcode code)
+  {
+    if (code == CURLE_NOT_BUILT_IN)
+    {
+      LOG(ERROR) << "Your libcurl does not contain a required feature, "
+                 << "please recompile Orthanc with -DUSE_SYSTEM_CURL=OFF";
+      throw OrthancException(ErrorCode_InternalError);
+    }
+
+    if (code != CURLE_OK)
+    {
+      LOG(ERROR) << "libCURL error: " + std::string(curl_easy_strerror(code));
+      throw OrthancException(ErrorCode_NetworkProtocol);
+    }
+
+    return code;
+  }
+
+
+  static size_t CurlBodyCallback(void *buffer, size_t size, size_t nmemb, void *payload)
+  {
+    ChunkedBuffer& target = *(static_cast<ChunkedBuffer*>(payload));
+
+    size_t length = size * nmemb;
+    if (length == 0)
+    {
+      return 0;
+    }
+    else
+    {
+      target.AddChunk(buffer, length);
+      return length;
+    }
+  }
+
+
+  struct CurlHeaderParameters
+  {
+    bool lowerCase_;
+    HttpClient::HttpHeaders* headers_;
+  };
+
+
+  static size_t CurlHeaderCallback(void *buffer, size_t size, size_t nmemb, void *payload)
+  {
+    CurlHeaderParameters& parameters = *(static_cast<CurlHeaderParameters*>(payload));
+    assert(parameters.headers_ != NULL);
+
+    size_t length = size * nmemb;
+    if (length == 0)
+    {
+      return 0;
+    }
+    else
+    {
+      std::string s(reinterpret_cast<const char*>(buffer), length);
+      std::size_t colon = s.find(':');
+      std::size_t eol = s.find("\r\n");
+      if (colon != std::string::npos &&
+          eol != std::string::npos)
+      {
+        std::string tmp(s.substr(0, colon));
+
+        if (parameters.lowerCase_)
+        {
+          Toolbox::ToLowerCase(tmp);
+        }
+
+        std::string key = Toolbox::StripSpaces(tmp);
+
+        if (!key.empty())
+        {
+          std::string value = Toolbox::StripSpaces(s.substr(colon + 1, eol));
+          (*parameters.headers_) [key] = value;
+        }
+      }
+
+      return length;
+    }
+  }
+
+
+  void HttpClient::Setup()
+  {
+    pimpl_->userHeaders_ = NULL;
+    pimpl_->defaultPostHeaders_ = NULL;
+    if ((pimpl_->defaultPostHeaders_ = curl_slist_append(pimpl_->defaultPostHeaders_, "Expect:")) == NULL)
+    {
+      throw OrthancException(ErrorCode_NotEnoughMemory);
+    }
+
+    pimpl_->curl_ = curl_easy_init();
+    if (!pimpl_->curl_)
+    {
+      curl_slist_free_all(pimpl_->defaultPostHeaders_);
+      throw OrthancException(ErrorCode_NotEnoughMemory);
+    }
+
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_WRITEFUNCTION, &CurlBodyCallback));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HEADER, 0));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_FOLLOWLOCATION, 1));
+
+    // This fixes the "longjmp causes uninitialized stack frame" crash
+    // that happens on modern Linux versions.
+    // http://stackoverflow.com/questions/9191668/error-longjmp-causes-uninitialized-stack-frame
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_NOSIGNAL, 1));
+
+    url_ = "";
+    method_ = HttpMethod_Get;
+    lastStatus_ = HttpStatus_200_Ok;
+    isVerbose_ = false;
+    timeout_ = GlobalParameters::GetInstance().GetDefaultTimeout();
+    GlobalParameters::GetInstance().GetDefaultProxy(proxy_);
+    GlobalParameters::GetInstance().GetSslConfiguration(verifyPeers_, caCertificates_);
+  }
+
+
+  HttpClient::HttpClient() : 
+    pimpl_(new PImpl), 
+    verifyPeers_(true),
+    pkcs11Enabled_(false),
+    headersToLowerCase_(true)
+  {
+    Setup();
+  }
+
+
+  HttpClient::HttpClient(const WebServiceParameters& service,
+                         const std::string& uri) : 
+    pimpl_(new PImpl), 
+    verifyPeers_(true),
+    headersToLowerCase_(true)
+  {
+    Setup();
+
+    if (service.GetUsername().size() != 0 && 
+        service.GetPassword().size() != 0)
+    {
+      SetCredentials(service.GetUsername().c_str(), 
+                     service.GetPassword().c_str());
+    }
+
+    if (!service.GetCertificateFile().empty())
+    {
+      SetClientCertificate(service.GetCertificateFile(),
+                           service.GetCertificateKeyFile(),
+                           service.GetCertificateKeyPassword());
+    }
+
+    SetPkcs11Enabled(service.IsPkcs11Enabled());
+
+    SetUrl(service.GetUrl() + uri);
+  }
+
+
+  HttpClient::~HttpClient()
+  {
+    curl_easy_cleanup(pimpl_->curl_);
+    curl_slist_free_all(pimpl_->defaultPostHeaders_);
+    ClearHeaders();
+  }
+
+
+  void HttpClient::SetVerbose(bool isVerbose)
+  {
+    isVerbose_ = isVerbose;
+
+    if (isVerbose_)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_VERBOSE, 1));
+    }
+    else
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_VERBOSE, 0));
+    }
+  }
+
+
+  void HttpClient::AddHeader(const std::string& key,
+                             const std::string& value)
+  {
+    if (key.empty())
+    {
+      throw OrthancException(ErrorCode_ParameterOutOfRange);
+    }
+
+    std::string s = key + ": " + value;
+
+    if ((pimpl_->userHeaders_ = curl_slist_append(pimpl_->userHeaders_, s.c_str())) == NULL)
+    {
+      throw OrthancException(ErrorCode_NotEnoughMemory);
+    }
+  }
+
+
+  void HttpClient::ClearHeaders()
+  {
+    if (pimpl_->userHeaders_ != NULL)
+    {
+      curl_slist_free_all(pimpl_->userHeaders_);
+      pimpl_->userHeaders_ = NULL;
+    }
+  }
+
+
+  bool HttpClient::ApplyInternal(std::string& answerBody,
+                                 HttpHeaders* answerHeaders)
+  {
+    answerBody.clear();
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_URL, url_.c_str()));
+
+    CurlHeaderParameters headerParameters;
+
+    if (answerHeaders == NULL)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HEADERFUNCTION, NULL));
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HEADERDATA, NULL));
+    }
+    else
+    {
+      headerParameters.lowerCase_ = headersToLowerCase_;
+      headerParameters.headers_ = answerHeaders;
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HEADERFUNCTION, &CurlHeaderCallback));
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HEADERDATA, &headerParameters));
+    }
+
+#if ORTHANC_SSL_ENABLED == 1
+    // Setup HTTPS-related options
+
+    if (verifyPeers_)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_CAINFO, caCertificates_.c_str()));
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSL_VERIFYHOST, 2));  // libcurl default is strict verifyhost
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSL_VERIFYPEER, 1)); 
+    }
+    else
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSL_VERIFYHOST, 0)); 
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSL_VERIFYPEER, 0)); 
+    }
+#endif
+
+    // Setup the HTTPS client certificate
+    if (!clientCertificateFile_.empty() &&
+        pkcs11Enabled_)
+    {
+      LOG(ERROR) << "Cannot enable both client certificates and PKCS#11 authentication";
+      throw OrthancException(ErrorCode_ParameterOutOfRange);
+    }
+
+    if (pkcs11Enabled_)
+    {
+#if ORTHANC_PKCS11_ENABLED == 1
+      if (GlobalParameters::GetInstance().IsPkcs11Initialized())
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLENGINE, Pkcs11::GetEngineIdentifier()));
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLKEYTYPE, "ENG"));
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLCERTTYPE, "ENG"));
+      }
+      else
+      {
+        LOG(ERROR) << "Cannot use PKCS#11 for a HTTPS request, because it has not been initialized";
+        throw OrthancException(ErrorCode_BadSequenceOfCalls);
+      }
+#else
+      LOG(ERROR) << "This version of Orthanc is compiled without support for PKCS#11";
+      throw OrthancException(ErrorCode_InternalError);
+#endif
+    }
+    else if (!clientCertificateFile_.empty())
+    {
+#if ORTHANC_SSL_ENABLED == 1
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLCERTTYPE, "PEM"));
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLCERT, clientCertificateFile_.c_str()));
+
+      if (!clientCertificateKeyPassword_.empty())
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_KEYPASSWD, clientCertificateKeyPassword_.c_str()));
+      }
+
+      // NB: If no "clientKeyFile_" is provided, the key must be
+      // prepended to the certificate file
+      if (!clientCertificateKeyFile_.empty())
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLKEYTYPE, "PEM"));
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_SSLKEY, clientCertificateKeyFile_.c_str()));
+      }
+#else
+      LOG(ERROR) << "This version of Orthanc is compiled without OpenSSL support, cannot use HTTPS client authentication";
+      throw OrthancException(ErrorCode_InternalError);
+#endif
+    }
+
+    // Reset the parameters from previous calls to Apply()
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HTTPHEADER, pimpl_->userHeaders_));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HTTPGET, 0L));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POST, 0L));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_NOBODY, 0L));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_CUSTOMREQUEST, NULL));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POSTFIELDS, NULL));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POSTFIELDSIZE, 0L));
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_PROXY, NULL));
+
+    if (redirectionFollowed_)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_FOLLOWLOCATION, 1L));
+    }
+    else
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_FOLLOWLOCATION, 0L));
+    }
+
+    // Set timeouts
+    if (timeout_ <= 0)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_TIMEOUT, 10));  /* default: 10 seconds */
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_CONNECTTIMEOUT, 10));  /* default: 10 seconds */
+    }
+    else
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_TIMEOUT, timeout_));
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_CONNECTTIMEOUT, timeout_));
+    }
+
+    if (credentials_.size() != 0)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_USERPWD, credentials_.c_str()));
+    }
+
+    if (proxy_.size() != 0)
+    {
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_PROXY, proxy_.c_str()));
+    }
+
+    switch (method_)
+    {
+    case HttpMethod_Get:
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HTTPGET, 1L));
+      break;
+
+    case HttpMethod_Post:
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POST, 1L));
+
+      if (pimpl_->userHeaders_ == NULL)
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HTTPHEADER, pimpl_->defaultPostHeaders_));
+      }
+
+      break;
+
+    case HttpMethod_Delete:
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_NOBODY, 1L));
+      CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_CUSTOMREQUEST, "DELETE"));
+      break;
+
+    case HttpMethod_Put:
+      // http://stackoverflow.com/a/7570281/881731: Don't use
+      // CURLOPT_PUT if there is a body
+
+      // CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_PUT, 1L));
+
+      curl_easy_setopt(pimpl_->curl_, CURLOPT_CUSTOMREQUEST, "PUT"); /* !!! */
+
+      if (pimpl_->userHeaders_ == NULL)
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_HTTPHEADER, pimpl_->defaultPostHeaders_));
+      }
+
+      break;
+
+    default:
+      throw OrthancException(ErrorCode_InternalError);
+    }
+
+
+    if (method_ == HttpMethod_Post ||
+        method_ == HttpMethod_Put)
+    {
+      if (body_.size() > 0)
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POSTFIELDS, body_.c_str()));
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POSTFIELDSIZE, body_.size()));
+      }
+      else
+      {
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POSTFIELDS, NULL));
+        CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_POSTFIELDSIZE, 0));
+      }
+    }
+
+
+    // Do the actual request
+    CURLcode code;
+    long status = 0;
+
+    ChunkedBuffer buffer;
+    CheckCode(curl_easy_setopt(pimpl_->curl_, CURLOPT_WRITEDATA, &buffer));
+
+    if (boost::starts_with(url_, "https://"))
+    {
+      code = OrthancHttpClientPerformSSL(pimpl_->curl_, &status);
+    }
+    else
+    {
+      code = GetHttpStatus(curl_easy_perform(pimpl_->curl_), pimpl_->curl_, &status);
+    }
+
+    CheckCode(code);
+
+    if (status == 0)
+    {
+      // This corresponds to a call to an inexistent host
+      lastStatus_ = HttpStatus_500_InternalServerError;
+    }
+    else
+    {
+      lastStatus_ = static_cast<HttpStatus>(status);
+    }
+
+    bool success = (status >= 200 && status < 300);
+
+    if (success)
+    {
+      buffer.Flatten(answerBody);
+    }
+    else
+    {
+      answerBody.clear();
+      LOG(INFO) << "Error in HTTP request, received HTTP status " << status 
+                << " (" << EnumerationToString(lastStatus_) << ")";
+    }
+
+    return success;
+  }
+
+
+  bool HttpClient::ApplyInternal(Json::Value& answerBody,
+                                 HttpClient::HttpHeaders* answerHeaders)
+  {
+    std::string s;
+    if (ApplyInternal(s, answerHeaders))
+    {
+      Json::Reader reader;
+      return reader.parse(s, answerBody);
+    }
+    else
+    {
+      return false;
+    }
+  }
+
+
+  void HttpClient::SetCredentials(const char* username,
+                                  const char* password)
+  {
+    credentials_ = std::string(username) + ":" + std::string(password);
+  }
+
+
+  void HttpClient::ConfigureSsl(bool httpsVerifyPeers,
+                                const std::string& httpsVerifyCertificates)
+  {
+#if ORTHANC_SSL_ENABLED == 1
+    if (httpsVerifyPeers)
+    {
+      if (httpsVerifyCertificates.empty())
+      {
+        LOG(WARNING) << "No certificates are provided to validate peers, "
+                     << "set \"HttpsCACertificates\" if you need to do HTTPS requests";
+      }
+      else
+      {
+        LOG(WARNING) << "HTTPS will use the CA certificates from this file: " << httpsVerifyCertificates;
+      }
+    }
+    else
+    {
+      LOG(WARNING) << "The verification of the peers in HTTPS requests is disabled";
+    }
+#endif
+
+    GlobalParameters::GetInstance().ConfigureSsl(httpsVerifyPeers, httpsVerifyCertificates);
+  }
+
+  
+  void HttpClient::GlobalInitialize()
+  {
+#if ORTHANC_SSL_ENABLED == 1
+    CheckCode(curl_global_init(CURL_GLOBAL_ALL));
+#else
+    CheckCode(curl_global_init(CURL_GLOBAL_ALL & ~CURL_GLOBAL_SSL));
+#endif
+  }
+
+
+  void HttpClient::GlobalFinalize()
+  {
+    curl_global_cleanup();
+
+#if ORTHANC_PKCS11_ENABLED == 1
+    Pkcs11::Finalize();
+#endif
+  }
+  
+
+  void HttpClient::SetDefaultProxy(const std::string& proxy)
+  {
+    GlobalParameters::GetInstance().SetDefaultProxy(proxy);
+  }
+
+
+  void HttpClient::SetDefaultTimeout(long timeout)
+  {
+    GlobalParameters::GetInstance().SetDefaultTimeout(timeout);
+  }
+
+
+  void HttpClient::ApplyAndThrowException(std::string& answerBody)
+  {
+    if (!Apply(answerBody))
+    {
+      ThrowException(GetLastStatus());
+    }
+  }
+
+  
+  void HttpClient::ApplyAndThrowException(Json::Value& answerBody)
+  {
+    if (!Apply(answerBody))
+    {
+      ThrowException(GetLastStatus());
+    }
+  }
+
+
+  void HttpClient::ApplyAndThrowException(std::string& answerBody,
+                                          HttpHeaders& answerHeaders)
+  {
+    if (!Apply(answerBody, answerHeaders))
+    {
+      ThrowException(GetLastStatus());
+    }
+  }
+  
+
+  void HttpClient::ApplyAndThrowException(Json::Value& answerBody,
+                                          HttpHeaders& answerHeaders)
+  {
+    if (!Apply(answerBody, answerHeaders))
+    {
+      ThrowException(GetLastStatus());
+    }
+  }
+
+
+  void HttpClient::SetClientCertificate(const std::string& certificateFile,
+                                        const std::string& certificateKeyFile,
+                                        const std::string& certificateKeyPassword)
+  {
+    if (certificateFile.empty())
+    {
+      throw OrthancException(ErrorCode_ParameterOutOfRange);
+    }
+
+    if (!Toolbox::IsRegularFile(certificateFile))
+    {
+      LOG(ERROR) << "Cannot open certificate file: " << certificateFile;
+      throw OrthancException(ErrorCode_InexistentFile);
+    }
+
+    if (!certificateKeyFile.empty() && 
+        !Toolbox::IsRegularFile(certificateKeyFile))
+    {
+      LOG(ERROR) << "Cannot open key file: " << certificateKeyFile;
+      throw OrthancException(ErrorCode_InexistentFile);
+    }
+
+    clientCertificateFile_ = certificateFile;
+    clientCertificateKeyFile_ = certificateKeyFile;
+    clientCertificateKeyPassword_ = certificateKeyPassword;
+  }
+
+
+  void HttpClient::InitializePkcs11(const std::string& module,
+                                    const std::string& pin,
+                                    bool verbose)
+  {
+#if ORTHANC_PKCS11_ENABLED == 1
+    LOG(INFO) << "Initializing PKCS#11 using " << module 
+              << (pin.empty() ? " (no PIN provided)" : " (PIN is provided)");
+    GlobalParameters::GetInstance().InitializePkcs11(module, pin, verbose);    
+#else
+    LOG(ERROR) << "This version of Orthanc is compiled without support for PKCS#11";
+    throw OrthancException(ErrorCode_InternalError);
+#endif
+  }
+
+
+  void HttpClient::InitializeOpenSsl()
+  {
+#if ORTHANC_SSL_ENABLED == 1
+    // https://wiki.openssl.org/index.php/Library_Initialization
+    SSL_library_init();
+    SSL_load_error_strings();
+    OpenSSL_add_all_algorithms();
+    ERR_load_crypto_strings();
+#endif
+  }
+
+
+  void HttpClient::FinalizeOpenSsl()
+  {
+ #if ORTHANC_SSL_ENABLED == 1
+    // Finalize OpenSSL
+    // https://wiki.openssl.org/index.php/Library_Initialization#Cleanup
+    FIPS_mode_set(0);
+    ENGINE_cleanup();
+    CONF_modules_unload(1);
+    EVP_cleanup();
+    CRYPTO_cleanup_all_ex_data();
+    ERR_remove_state(0);
+    ERR_free_strings();
+#endif
+  }
+}