1 files changed, 26 insertions, 0 deletions
diff --git a/Swiften/TLS/OpenSSL/OpenSSLContextFactory.cpp b/Swiften/TLS/OpenSSL/OpenSSLContextFactory.cpp
index af0966e..9d0ad72 100644
--- a/Swiften/TLS/OpenSSL/OpenSSLContextFactory.cpp
+++ b/Swiften/TLS/OpenSSL/OpenSSLContextFactory.cpp
@@ -6,9 +6,15 @@
 
 #include <Swiften/TLS/OpenSSL/OpenSSLContextFactory.h>
 
+#include <openssl/bio.h>
+#include <openssl/dh.h>
+#include <openssl/pem.h>
+
 #include <Swiften/Base/Log.h>
 #include <Swiften/TLS/OpenSSL/OpenSSLContext.h>
 
+#pragma clang diagnostic ignored "-Wshorten-64-to-32"
+
 namespace Swift {
 
 bool OpenSSLContextFactory::canCreate() const {
@@ -19,6 +25,26 @@ TLSContext* OpenSSLContextFactory::createTLSContext(const TLSOptions&, TLSContex
     return new OpenSSLContext(mode);
 }
 
+ByteArray OpenSSLContextFactory::convertDHParametersFromPEMToDER(const std::string& dhParametersInPEM) {
+    ByteArray dhParametersInDER;
+
+    auto bio = std::unique_ptr<BIO, decltype(&BIO_free)>(BIO_new(BIO_s_mem()), BIO_free);
+    if (bio) {
+        BIO_write(bio.get(), dhParametersInPEM.data(), dhParametersInPEM.size());
+        if (auto params = PEM_read_bio_DHparams(bio.get(), nullptr, nullptr, nullptr)) {
+            unsigned char* buffer = nullptr;
+            auto len = i2d_DHparams(params, &buffer);
+            if (len > 0) {
+                dhParametersInDER = createByteArray(buffer, static_cast<size_t>(len));
+                free(buffer);
+            }
+            DH_free(params);
+
+        }
+    }
+    return dhParametersInDER;
+}
+
 void OpenSSLContextFactory::setCheckCertificateRevocation(bool check) {
     if (check) {
         SWIFT_LOG(warning) << "CRL Checking not supported for OpenSSL" << std::endl;