Refactored common impl into gssapi_mechanism_base.

E.g., both client and server need to produce and process GSSAPI tokens.

src/gssapi_mechanism_base.cpp

@@ -0,0 +1,77 @@
+/*
+    Copyright (c) 2007-2013 Contributors as noted in the AUTHORS file
+
+    This file is part of 0MQ.
+
+    0MQ is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    0MQ 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 Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "platform.hpp"
+#ifdef ZMQ_HAVE_WINDOWS
+#include "windows.hpp"
+#endif
+
+#include <string.h>
+#include <string>
+
+#include "msg.hpp"
+#include "session_base.hpp"
+#include "err.hpp"
+#include "gssapi_mechanism_base.hpp"
+#include "wire.hpp"
+
+zmq::gssapi_mechanism_base_t::gssapi_mechanism_base_t () :
+    gss_continue_needed (false)
+{
+}
+
+zmq::gssapi_mechanism_base_t::~gssapi_mechanism_base_t ()
+{
+}
+
+int zmq::gssapi_mechanism_base_t::produce_token (msg_t *msg_) const
+{
+    unsigned char * const command_buffer = (unsigned char *) malloc (512);
+    alloc_assert (command_buffer);
+
+    unsigned char *ptr = command_buffer;
+
+    //  Add command name
+    memcpy (ptr, "\x05TOKEN", 6);
+    ptr += 6;
+
+    const size_t command_size = ptr - command_buffer;
+    const int rc = msg_->init_size (command_size);
+    errno_assert (rc == 0);
+    memcpy (msg_->data (), command_buffer, command_size);
+    free (command_buffer);
+
+    return 0;
+}
+
+int zmq::gssapi_mechanism_base_t::process_token (msg_t *msg_)
+{
+    const unsigned char *ptr = static_cast <unsigned char *> (msg_->data ());
+    size_t bytes_left = msg_->size ();
+
+    if (bytes_left < 6 || memcmp (ptr, "\x05TOKEN", 6)) {
+        errno = EPROTO;
+        return -1;
+    }
+    ptr += 6;
+    bytes_left -= 6;
+
+    return 0;
+}
+