Problem: code duplication between curve_client_t and curve_server_t decode and encode

Solution: extracted common base class curve_mechanism_base_t

CMakeLists.txt

@@ -484,6 +484,7 @@ set (cxx-sources
         client.cpp
         clock.cpp
         ctx.cpp
+        curve_mechanism_base.cpp
         curve_client.cpp
         curve_server.cpp
         dealer.cpp
@@ -504,6 +505,7 @@ set (cxx-sources
         mailbox.cpp
         mailbox_safe.cpp
         mechanism.cpp
+        mechanism_base.cpp
         metadata.cpp
         msg.cpp
         mtrie.cpp

Makefile.am

@@ -38,6 +38,8 @@ src_libzmq_la_SOURCES = \
 	src/curve_client.cpp \
 	src/curve_client.hpp \
 	src/curve_client_tools.hpp \
+	src/curve_mechanism_base.cpp \
+	src/curve_mechanism_base.hpp \
 	src/curve_server.cpp \
 	src/curve_server.hpp \
 	src/dbuffer.hpp \
@@ -97,6 +99,8 @@ src_libzmq_la_SOURCES = \
 	src/mailbox_safe.hpp \
 	src/mechanism.cpp \
 	src/mechanism.hpp  \
+	src/mechanism_base.cpp \
+	src/mechanism_base.hpp  \
 	src/metadata.cpp \
 	src/metadata.hpp \
 	src/msg.cpp \

builds/gyp/project.gyp

@@ -80,6 +80,9 @@
         '../../src/ctx.hpp',
         '../../src/curve_client.cpp',
         '../../src/curve_client.hpp',
+        '../../src/curve_client_tools.hpp',
+        '../../src/curve_mechanism_base.cpp',
+        '../../src/curve_mechanism_base.hpp',
         '../../src/curve_server.cpp',
         '../../src/curve_server.hpp',
         '../../src/dbuffer.hpp',
@@ -136,6 +139,8 @@
         '../../src/mailbox_safe.hpp',
         '../../src/mechanism.cpp',
         '../../src/mechanism.hpp ',
+        '../../src/mechanism_base.cpp',
+        '../../src/mechanism_base.hpp ',
         '../../src/metadata.cpp',
         '../../src/metadata.hpp',
         '../../src/msg.cpp',

builds/msvc/vs2008/libzmq/libzmq.vcproj

@@ -121,6 +121,7 @@
       <File RelativePath="..\..\..\..\src\kqueue.cpp" />
       <File RelativePath="..\..\..\..\src\lb.cpp" />
       <File RelativePath="..\..\..\..\src\mailbox.cpp" />
+      <File RelativePath="..\..\..\..\src\mechanism_base.cpp" />
       <File RelativePath="..\..\..\..\src\mechanism.cpp" />
       <File RelativePath="..\..\..\..\src\metadata.cpp" />
       <File RelativePath="..\..\..\..\src\msg.cpp" />
@@ -173,6 +174,7 @@
       <File RelativePath="..\..\..\..\src\udp_engine.cpp" />
       <File RelativePath="..\..\..\..\src\xpub.cpp" />
       <File RelativePath="..\..\..\..\src\xsub.cpp" />
+      <File RelativePath="..\..\..\..\src\zap_client.cpp" />
       <File RelativePath="..\..\..\..\src\zmq.cpp" />
       <File RelativePath="..\..\..\..\src\zmq_utils.cpp" />
     </Filter>

builds/msvc/vs2010/libzmq/libzmq.vcxproj

@@ -180,6 +180,7 @@
     <ClCompile Include="..\..\..\..\src\clock.cpp" />
     <ClCompile Include="..\..\..\..\src\ctx.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_client.cpp" />
+    <ClCompile Include="..\..\..\..\src\curve_mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_server.cpp" />
     <ClCompile Include="..\..\..\..\src\dealer.cpp" />
     <ClCompile Include="..\..\..\..\src\decoder_allocators.cpp" />
@@ -205,6 +206,7 @@
     <ClCompile Include="..\..\..\..\src\mailbox.cpp" />
     <ClCompile Include="..\..\..\..\src\mailbox_safe.cpp" />
     <ClCompile Include="..\..\..\..\src\mechanism.cpp" />
+    <ClCompile Include="..\..\..\..\src\mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\metadata.cpp" />
     <ClCompile Include="..\..\..\..\src\msg.cpp" />
     <ClCompile Include="..\..\..\..\src\mtrie.cpp" />
@@ -266,6 +268,7 @@
     <ClCompile Include="..\..\..\..\src\v2_encoder.cpp" />
     <ClCompile Include="..\..\..\..\src\xpub.cpp" />
     <ClCompile Include="..\..\..\..\src\xsub.cpp" />
+    <ClCompile Include="..\..\..\..\src\zap_client.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq_utils.cpp" />
   </ItemGroup>

builds/msvc/vs2012/libzmq/libzmq.vcxproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Label="Globals">
     <ProjectGuid>{641C5F36-32EE-4323-B740-992B651CF9D6}</ProjectGuid>
@@ -180,6 +180,7 @@
     <ClCompile Include="..\..\..\..\src\clock.cpp" />
     <ClCompile Include="..\..\..\..\src\ctx.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_client.cpp" />
+    <ClCompile Include="..\..\..\..\src\curve_mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_server.cpp" />
     <ClCompile Include="..\..\..\..\src\dealer.cpp" />
     <ClCompile Include="..\..\..\..\src\decoder_allocators.cpp" />
@@ -205,6 +206,7 @@
     <ClCompile Include="..\..\..\..\src\mailbox.cpp" />
     <ClCompile Include="..\..\..\..\src\mailbox_safe.cpp" />
     <ClCompile Include="..\..\..\..\src\mechanism.cpp" />
+    <ClCompile Include="..\..\..\..\src\mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\metadata.cpp" />
     <ClCompile Include="..\..\..\..\src\msg.cpp" />
     <ClCompile Include="..\..\..\..\src\mtrie.cpp" />
@@ -266,6 +268,7 @@
     <ClCompile Include="..\..\..\..\src\v2_encoder.cpp" />
     <ClCompile Include="..\..\..\..\src\xpub.cpp" />
     <ClCompile Include="..\..\..\..\src\xsub.cpp" />
+    <ClCompile Include="..\..\..\..\src\zap_client.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq_utils.cpp" />
   </ItemGroup>

builds/msvc/vs2013/libzmq/libzmq.vcxproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Label="Globals">
     <ProjectGuid>{641C5F36-32EE-4323-B740-992B651CF9D6}</ProjectGuid>
@@ -180,6 +180,7 @@
     <ClCompile Include="..\..\..\..\src\clock.cpp" />
     <ClCompile Include="..\..\..\..\src\ctx.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_client.cpp" />
+    <ClCompile Include="..\..\..\..\src\curve_mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_server.cpp" />
     <ClCompile Include="..\..\..\..\src\dealer.cpp" />
     <ClCompile Include="..\..\..\..\src\decoder_allocators.cpp" />
@@ -205,6 +206,7 @@
     <ClCompile Include="..\..\..\..\src\mailbox.cpp" />
     <ClCompile Include="..\..\..\..\src\mailbox_safe.cpp" />
     <ClCompile Include="..\..\..\..\src\mechanism.cpp" />
+    <ClCompile Include="..\..\..\..\src\mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\metadata.cpp" />
     <ClCompile Include="..\..\..\..\src\msg.cpp" />
     <ClCompile Include="..\..\..\..\src\mtrie.cpp" />
@@ -266,6 +268,7 @@
     <ClCompile Include="..\..\..\..\src\v2_encoder.cpp" />
     <ClCompile Include="..\..\..\..\src\xpub.cpp" />
     <ClCompile Include="..\..\..\..\src\xsub.cpp" />
+    <ClCompile Include="..\..\..\..\src\zap_client.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq_utils.cpp" />
   </ItemGroup>

builds/msvc/vs2015/libzmq/libzmq.vcxproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Label="Globals">
     <ProjectGuid>{641C5F36-32EE-4323-B740-992B651CF9D6}</ProjectGuid>
@@ -180,6 +180,7 @@
     <ClCompile Include="..\..\..\..\src\clock.cpp" />
     <ClCompile Include="..\..\..\..\src\ctx.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_client.cpp" />
+    <ClCompile Include="..\..\..\..\src\curve_mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_server.cpp" />
     <ClCompile Include="..\..\..\..\src\dealer.cpp" />
     <ClCompile Include="..\..\..\..\src\decoder_allocators.cpp" />
@@ -205,6 +206,7 @@
     <ClCompile Include="..\..\..\..\src\mailbox.cpp" />
     <ClCompile Include="..\..\..\..\src\mailbox_safe.cpp" />
     <ClCompile Include="..\..\..\..\src\mechanism.cpp" />
+    <ClCompile Include="..\..\..\..\src\mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\metadata.cpp" />
     <ClCompile Include="..\..\..\..\src\msg.cpp" />
     <ClCompile Include="..\..\..\..\src\mtrie.cpp" />
@@ -266,6 +268,7 @@
     <ClCompile Include="..\..\..\..\src\v2_encoder.cpp" />
     <ClCompile Include="..\..\..\..\src\xpub.cpp" />
     <ClCompile Include="..\..\..\..\src\xsub.cpp" />
+    <ClCompile Include="..\..\..\..\src\zap_client.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq_utils.cpp" />
   </ItemGroup>

builds/msvc/vs2015_xp/libzmq.vcxproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="14.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ItemGroup Label="ProjectConfigurations">
     <ProjectConfiguration Include="Debug|Win32">
@@ -152,6 +152,7 @@
     <ClCompile Include="..\..\..\src\clock.cpp" />
     <ClCompile Include="..\..\..\src\ctx.cpp" />
     <ClCompile Include="..\..\..\src\curve_client.cpp" />
+    <ClCompile Include="..\..\..\src\curve_mechanism_base.cpp" />
     <ClCompile Include="..\..\..\src\curve_server.cpp" />
     <ClCompile Include="..\..\..\src\dealer.cpp" />
     <ClCompile Include="..\..\..\src\decoder_allocators.cpp" />
@@ -177,6 +178,7 @@
     <ClCompile Include="..\..\..\src\mailbox.cpp" />
     <ClCompile Include="..\..\..\src\mailbox_safe.cpp" />
     <ClCompile Include="..\..\..\src\mechanism.cpp" />
+    <ClCompile Include="..\..\..\src\mechanism_base.cpp" />
     <ClCompile Include="..\..\..\src\metadata.cpp" />
     <ClCompile Include="..\..\..\src\msg.cpp" />
     <ClCompile Include="..\..\..\src\mtrie.cpp" />
@@ -242,6 +244,7 @@
     <ClCompile Include="..\..\..\src\vmci_listener.cpp" />
     <ClCompile Include="..\..\..\src\xpub.cpp" />
     <ClCompile Include="..\..\..\src\xsub.cpp" />
+    <ClCompile Include="..\..\..\src\zap_client.cpp" />
     <ClCompile Include="..\..\..\src\zmq.cpp" />
   </ItemGroup>
   <ItemGroup>

builds/msvc/vs2017/libzmq/libzmq.vcxproj

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup Label="Globals">
     <ProjectGuid>{641C5F36-32EE-4323-B740-992B651CF9D6}</ProjectGuid>
@@ -180,6 +180,7 @@
     <ClCompile Include="..\..\..\..\src\clock.cpp" />
     <ClCompile Include="..\..\..\..\src\ctx.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_client.cpp" />
+    <ClCompile Include="..\..\..\..\src\curve_mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\curve_server.cpp" />
     <ClCompile Include="..\..\..\..\src\dealer.cpp" />
     <ClCompile Include="..\..\..\..\src\decoder_allocators.cpp" />
@@ -205,6 +206,7 @@
     <ClCompile Include="..\..\..\..\src\mailbox.cpp" />
     <ClCompile Include="..\..\..\..\src\mailbox_safe.cpp" />
     <ClCompile Include="..\..\..\..\src\mechanism.cpp" />
+    <ClCompile Include="..\..\..\..\src\mechanism_base.cpp" />
     <ClCompile Include="..\..\..\..\src\metadata.cpp" />
     <ClCompile Include="..\..\..\..\src\msg.cpp" />
     <ClCompile Include="..\..\..\..\src\mtrie.cpp" />
@@ -266,6 +268,7 @@
     <ClCompile Include="..\..\..\..\src\v2_encoder.cpp" />
     <ClCompile Include="..\..\..\..\src\xpub.cpp" />
     <ClCompile Include="..\..\..\..\src\xsub.cpp" />
+    <ClCompile Include="..\..\..\..\src\zap_client.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq.cpp" />
     <ClCompile Include="..\..\..\..\src\zmq_utils.cpp" />
   </ItemGroup>

src/curve_client.cpp

@@ -42,12 +42,12 @@
 zmq::curve_client_t::curve_client_t (session_base_t *session_,
                                      const options_t &options_) :
     mechanism_base_t (session_, options_),
+    curve_mechanism_base_t (
+      session_, options_, "CurveZMQMESSAGEC", "CurveZMQMESSAGES"),
     state (send_hello),
     tools (options_.curve_public_key,
            options_.curve_secret_key,
-           options_.curve_server_key),
+           options_.curve_server_key)
-    cn_nonce (1),
-    cn_peer_nonce (1)
 {
 }
 
@@ -113,134 +113,13 @@ int zmq::curve_client_t::process_handshake_command (msg_t *msg_)
 int zmq::curve_client_t::encode (msg_t *msg_)
 {
     zmq_assert (state == connected);
-
+    return curve_mechanism_base_t::encode (msg_);
-    uint8_t flags = 0;
-    if (msg_->flags () & msg_t::more)
-        flags |= 0x01;
-    if (msg_->flags () & msg_t::command)
-        flags |= 0x02;
-
-    uint8_t message_nonce [crypto_box_NONCEBYTES];
-    memcpy (message_nonce, "CurveZMQMESSAGEC", 16);
-    put_uint64 (message_nonce + 16, cn_nonce);
-
-    const size_t mlen = crypto_box_ZEROBYTES + 1 + msg_->size ();
-
-    uint8_t *message_plaintext = static_cast <uint8_t *> (malloc (mlen));
-    alloc_assert (message_plaintext);
-
-    memset (message_plaintext, 0, crypto_box_ZEROBYTES);
-    message_plaintext [crypto_box_ZEROBYTES] = flags;
-    memcpy (message_plaintext + crypto_box_ZEROBYTES + 1,
-            msg_->data (), msg_->size ());
-
-    uint8_t *message_box = static_cast <uint8_t *> (malloc (mlen));
-    alloc_assert (message_box);
-
-    int rc = crypto_box_afternm (message_box, message_plaintext, mlen,
-                                 message_nonce, tools.cn_precom);
-    zmq_assert (rc == 0);
-
-    rc = msg_->close ();
-    zmq_assert (rc == 0);
-
-    rc = msg_->init_size (16 + mlen - crypto_box_BOXZEROBYTES);
-    zmq_assert (rc == 0);
-
-    uint8_t *message = static_cast <uint8_t *> (msg_->data ());
-
-    memcpy (message, "\x07MESSAGE", 8);
-    memcpy (message + 8, message_nonce + 16, 8);
-    memcpy (message + 16, message_box + crypto_box_BOXZEROBYTES,
-            mlen - crypto_box_BOXZEROBYTES);
-
-    free (message_plaintext);
-    free (message_box);
-
-    cn_nonce++;
-
-    return 0;
 }
 
 int zmq::curve_client_t::decode (msg_t *msg_)
 {
     zmq_assert (state == connected);
-    int rc = check_basic_command_structure (msg_);
+    return curve_mechanism_base_t::decode (msg_);
-    if (rc == -1)
-        return rc;
-
-    const uint8_t *message = static_cast <uint8_t *> (msg_->data ());
-    if (msg_->size() < 8 || memcmp (message, "\x07MESSAGE", 8)) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (),
-          ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);
-        errno = EPROTO;
-        return -1;
-    }
-
-    if (msg_->size () < 33) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (),
-          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_MESSAGE);
-        errno = EPROTO;
-        return -1;
-    }
-
-    uint8_t message_nonce [crypto_box_NONCEBYTES];
-    memcpy (message_nonce, "CurveZMQMESSAGES", 16);
-    memcpy (message_nonce + 16, message + 8, 8);
-    uint64_t nonce = get_uint64(message + 8);
-    if (nonce <= cn_peer_nonce) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (),
-          ZMQ_PROTOCOL_ERROR_ZMTP_INVALID_SEQUENCE);
-        errno = EPROTO;
-        return -1;
-    }
-    cn_peer_nonce = nonce;
-
-    const size_t clen = crypto_box_BOXZEROBYTES + (msg_->size () - 16);
-
-    uint8_t *message_plaintext = static_cast <uint8_t *> (malloc (clen));
-    alloc_assert (message_plaintext);
-
-    uint8_t *message_box = static_cast <uint8_t *> (malloc (clen));
-    alloc_assert (message_box);
-
-    memset (message_box, 0, crypto_box_BOXZEROBYTES);
-    memcpy (message_box + crypto_box_BOXZEROBYTES,
-            message + 16, msg_->size () - 16);
-
-    rc = crypto_box_open_afternm (message_plaintext, message_box, clen,
-                                  message_nonce, tools.cn_precom);
-    if (rc == 0) {
-        rc = msg_->close ();
-        zmq_assert (rc == 0);
-
-        rc = msg_->init_size (clen - 1 - crypto_box_ZEROBYTES);
-        zmq_assert (rc == 0);
-
-        const uint8_t flags = message_plaintext [crypto_box_ZEROBYTES];
-        if (flags & 0x01)
-            msg_->set_flags (msg_t::more);
-        if (flags & 0x02)
-            msg_->set_flags (msg_t::command);
-
-        memcpy (msg_->data (),
-                message_plaintext + crypto_box_ZEROBYTES + 1,
-                msg_->size ());
-    }
-    else {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (),
-          ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC);
-        errno = EPROTO;
-    }
-
-    free (message_plaintext);
-    free (message_box);
-
-    return rc;
 }
 
 zmq::mechanism_t::status_t zmq::curve_client_t::status () const
@@ -281,7 +160,7 @@ int zmq::curve_client_t::produce_hello (msg_t *msg_)
 int zmq::curve_client_t::process_welcome (const uint8_t *msg_data,
                                           size_t msg_size)
 {
-    int rc = tools.process_welcome (msg_data, msg_size);
+    int rc = tools.process_welcome (msg_data, msg_size, cn_precom);
 
     if (rc == -1) {
         session->get_socket ()->event_handshake_failed_protocol (
@@ -358,7 +237,7 @@ int zmq::curve_client_t::process_ready (
     cn_peer_nonce = get_uint64(msg_data + 6);
 
     int rc = crypto_box_open_afternm (ready_plaintext, ready_box,
-                                      clen, ready_nonce, tools.cn_precom);
+                                      clen, ready_nonce, cn_precom);
     free (ready_box);
 
     if (rc != 0) {

src/curve_client.hpp

@@ -32,7 +32,7 @@
 
 #ifdef ZMQ_HAVE_CURVE
 
-#include "mechanism.hpp"
+#include "curve_mechanism_base.hpp"
 #include "options.hpp"
 #include "curve_client_tools.hpp"
 
@@ -42,7 +42,7 @@ namespace zmq
     class msg_t;
     class session_base_t;
 
-    class curve_client_t : public mechanism_base_t
+    class curve_client_t : public curve_mechanism_base_t
     {
     public:
 
@@ -72,11 +72,7 @@ namespace zmq
 
         //  CURVE protocol tools
         curve_client_tools_t tools;
-
+       
-        //  Nonce
-        uint64_t cn_nonce;
-        uint64_t cn_peer_nonce;
-
         int produce_hello (msg_t *msg_);
         int process_welcome (const uint8_t *cmd_data, size_t data_size);
         int produce_initiate (msg_t *msg_);

src/curve_client_tools.hpp

@@ -251,7 +251,9 @@ struct curve_client_tools_t
         return produce_hello (data, server_key, cn_nonce, cn_public, cn_secret);
     }
 
-    int process_welcome (const uint8_t *msg_data, size_t msg_size)
+    int process_welcome (const uint8_t *msg_data,
+                         size_t msg_size,
+                         uint8_t *cn_precom)
     {
         return process_welcome (msg_data, msg_size, server_key, cn_secret,
                                 cn_server, cn_cookie, cn_precom);
@@ -289,10 +291,6 @@ struct curve_client_tools_t
     //  Cookie received from server
     uint8_t cn_cookie[16 + 80];
 
-    //  Intermediary buffer used to speed up boxing and unboxing.
-    uint8_t cn_precom[crypto_box_BEFORENMBYTES];
-
-
   private:
     template <size_t N>
     static bool is_handshake_command (const uint8_t *msg_data,

src/curve_mechanism_base.cpp

@@ -0,0 +1,181 @@
+/*
+    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
+
+    This file is part of libzmq, the ZeroMQ core engine in C++.
+
+    libzmq is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    As a special exception, the Contributors give you permission to link
+    this library with independent modules to produce an executable,
+    regardless of the license terms of these independent modules, and to
+    copy and distribute the resulting executable under terms of your choice,
+    provided that you also meet, for each linked independent module, the
+    terms and conditions of the license of that module. An independent
+    module is a module which is not derived from or based on this library.
+    If you modify this library, you must extend this exception to your
+    version of the library.
+
+    libzmq 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 "precompiled.hpp"
+#include "curve_mechanism_base.hpp"
+#include "msg.hpp"
+#include "wire.hpp"
+#include "session_base.hpp"
+
+#ifdef ZMQ_HAVE_CURVE
+
+zmq::curve_mechanism_base_t::curve_mechanism_base_t (
+  session_base_t *session_,
+  const options_t &options_,
+  const char *encode_nonce_prefix_,
+  const char *decode_nonce_prefix_) :
+    mechanism_base_t (session_, options_),
+    encode_nonce_prefix (encode_nonce_prefix_),
+    decode_nonce_prefix (decode_nonce_prefix_),
+    cn_nonce (1),
+    cn_peer_nonce (1)
+{
+}
+
+int zmq::curve_mechanism_base_t::encode (msg_t *msg_)
+{
+    const size_t mlen = crypto_box_ZEROBYTES + 1 + msg_->size ();
+
+    uint8_t message_nonce [crypto_box_NONCEBYTES];
+    memcpy (message_nonce, encode_nonce_prefix, 16);
+    put_uint64 (message_nonce + 16, cn_nonce);
+
+    uint8_t flags = 0;
+    if (msg_->flags () & msg_t::more)
+        flags |= 0x01;
+    if (msg_->flags () & msg_t::command)
+        flags |= 0x02;
+
+    uint8_t *message_plaintext = static_cast <uint8_t *> (malloc (mlen));
+    alloc_assert (message_plaintext);
+
+    memset (message_plaintext, 0, crypto_box_ZEROBYTES);
+    message_plaintext [crypto_box_ZEROBYTES] = flags;
+    memcpy (message_plaintext + crypto_box_ZEROBYTES + 1,
+            msg_->data (), msg_->size ());
+
+    uint8_t *message_box = static_cast <uint8_t *> (malloc (mlen));
+    alloc_assert (message_box);
+
+    int rc = crypto_box_afternm (message_box, message_plaintext,
+                                 mlen, message_nonce, cn_precom);
+    zmq_assert (rc == 0);
+
+    rc = msg_->close ();
+    zmq_assert (rc == 0);
+
+    rc = msg_->init_size (16 + mlen - crypto_box_BOXZEROBYTES);
+    zmq_assert (rc == 0);
+
+    uint8_t *message = static_cast <uint8_t *> (msg_->data ());
+
+    memcpy (message, "\x07MESSAGE", 8);
+    memcpy (message + 8, message_nonce + 16, 8);
+    memcpy (message + 16, message_box + crypto_box_BOXZEROBYTES,
+            mlen - crypto_box_BOXZEROBYTES);
+
+    free (message_plaintext);
+    free (message_box);
+
+    cn_nonce++;
+
+    return 0;
+}
+
+int zmq::curve_mechanism_base_t::decode (msg_t *msg_)
+{
+    int rc = check_basic_command_structure (msg_);
+    if (rc == -1)
+      return -1;
+
+    const size_t size = msg_->size ();
+    const uint8_t *message = static_cast <uint8_t *> (msg_->data ());
+    
+    if (size < 8 || memcmp (message, "\x07MESSAGE", 8)) {
+        session->get_socket ()->event_handshake_failed_protocol (
+          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);
+        errno = EPROTO;
+        return -1;
+    }
+
+    if (size < 33) {
+        session->get_socket ()->event_handshake_failed_protocol (
+          session->get_endpoint (),
+          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_MESSAGE);
+        errno = EPROTO;
+        return -1;
+    }
+
+    uint8_t message_nonce [crypto_box_NONCEBYTES];
+    memcpy (message_nonce, decode_nonce_prefix, 16);
+    memcpy (message_nonce + 16, message + 8, 8);
+    uint64_t nonce = get_uint64(message + 8);
+    if (nonce <= cn_peer_nonce) {
+        session->get_socket ()->event_handshake_failed_protocol (
+          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_INVALID_SEQUENCE);
+        errno = EPROTO;
+        return -1;
+    }
+    cn_peer_nonce = nonce;
+
+    const size_t clen = crypto_box_BOXZEROBYTES + msg_->size () - 16;
+
+    uint8_t *message_plaintext = static_cast <uint8_t *> (malloc (clen));
+    alloc_assert (message_plaintext);
+
+    uint8_t *message_box = static_cast <uint8_t *> (malloc (clen));
+    alloc_assert (message_box);
+
+    memset (message_box, 0, crypto_box_BOXZEROBYTES);
+    memcpy (message_box + crypto_box_BOXZEROBYTES,
+            message + 16, msg_->size () - 16);
+
+    rc = crypto_box_open_afternm (message_plaintext, message_box, clen,
+                                  message_nonce, cn_precom);
+    if (rc == 0) {
+        rc = msg_->close ();
+        zmq_assert (rc == 0);
+
+        rc = msg_->init_size (clen - 1 - crypto_box_ZEROBYTES);
+        zmq_assert (rc == 0);
+
+        const uint8_t flags = message_plaintext [crypto_box_ZEROBYTES];
+        if (flags & 0x01)
+            msg_->set_flags (msg_t::more);
+        if (flags & 0x02)
+            msg_->set_flags (msg_t::command);
+
+        memcpy (msg_->data (),
+                message_plaintext + crypto_box_ZEROBYTES + 1,
+                msg_->size ());
+    }
+    else {
+        // CURVE I : connection key used for MESSAGE is wrong
+        session->get_socket ()->event_handshake_failed_protocol (
+          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC);
+        errno = EPROTO;
+    }
+    free (message_plaintext);
+    free (message_box);
+
+    return rc;
+}
+
+#endif

src/curve_mechanism_base.hpp

@@ -0,0 +1,79 @@
+/*
+    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
+
+    This file is part of libzmq, the ZeroMQ core engine in C++.
+
+    libzmq is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    As a special exception, the Contributors give you permission to link
+    this library with independent modules to produce an executable,
+    regardless of the license terms of these independent modules, and to
+    copy and distribute the resulting executable under terms of your choice,
+    provided that you also meet, for each linked independent module, the
+    terms and conditions of the license of that module. An independent
+    module is a module which is not derived from or based on this library.
+    If you modify this library, you must extend this exception to your
+    version of the library.
+
+    libzmq 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/>.
+*/
+
+#ifndef __ZMQ_CURVE_MECHANISM_BASE_HPP_INCLUDED__
+#define __ZMQ_CURVE_MECHANISM_BASE_HPP_INCLUDED__
+
+#ifdef ZMQ_HAVE_CURVE
+
+#if defined(ZMQ_USE_TWEETNACL)
+#include "tweetnacl.h"
+#elif defined(ZMQ_USE_LIBSODIUM)
+#include "sodium.h"
+#endif
+
+#if crypto_box_NONCEBYTES != 24 || crypto_box_PUBLICKEYBYTES != 32             \
+  || crypto_box_SECRETKEYBYTES != 32 || crypto_box_ZEROBYTES != 32             \
+  || crypto_box_BOXZEROBYTES != 16 || crypto_secretbox_NONCEBYTES != 24        \
+  || crypto_secretbox_ZEROBYTES != 32 || crypto_secretbox_BOXZEROBYTES != 16
+#error "CURVE library not built properly"
+#endif
+
+#include "mechanism_base.hpp"
+#include "options.hpp"
+
+namespace zmq
+{
+class curve_mechanism_base_t : public virtual mechanism_base_t
+{
+  public:
+    curve_mechanism_base_t (session_base_t *session_,
+                            const options_t &options_,
+                            const char *encode_nonce_prefix_,
+                            const char *decode_nonce_prefix_);
+
+    // mechanism implementation
+    virtual int encode (msg_t *msg_);
+    virtual int decode (msg_t *msg_);
+
+  protected:
+    const char *encode_nonce_prefix;
+    const char *decode_nonce_prefix;
+
+    uint64_t cn_nonce;
+    uint64_t cn_peer_nonce;
+
+    //  Intermediary buffer used to speed up boxing and unboxing.
+    uint8_t cn_precom [crypto_box_BEFORENMBYTES];
+};
+}
+
+#endif
+
+#endif

src/curve_server.cpp

@@ -44,8 +44,8 @@ zmq::curve_server_t::curve_server_t (session_base_t *session_,
     mechanism_base_t (session_, options_),
     zap_client_common_handshake_t (
       session_, peer_address_, options_, sending_ready),
-    cn_nonce (1),
+    curve_mechanism_base_t (
-    cn_peer_nonce (1)
+      session_, options_, "CurveZMQMESSAGES", "CurveZMQMESSAGEC")
 {
     int rc;
     //  Fetch our secret key from socket options
@@ -125,134 +125,13 @@ int zmq::curve_server_t::process_handshake_command (msg_t *msg_)
 int zmq::curve_server_t::encode (msg_t *msg_)
 {
     zmq_assert (state == ready);
-
+    return curve_mechanism_base_t::encode (msg_);
-    const size_t mlen = crypto_box_ZEROBYTES + 1 + msg_->size ();
-
-    uint8_t message_nonce [crypto_box_NONCEBYTES];
-    memcpy (message_nonce, "CurveZMQMESSAGES", 16);
-    put_uint64 (message_nonce + 16, cn_nonce);
-
-    uint8_t flags = 0;
-    if (msg_->flags () & msg_t::more)
-        flags |= 0x01;
-    if (msg_->flags () & msg_t::command)
-        flags |= 0x02;
-
-    uint8_t *message_plaintext = static_cast <uint8_t *> (malloc (mlen));
-    alloc_assert (message_plaintext);
-
-    memset (message_plaintext, 0, crypto_box_ZEROBYTES);
-    message_plaintext [crypto_box_ZEROBYTES] = flags;
-    memcpy (message_plaintext + crypto_box_ZEROBYTES + 1,
-            msg_->data (), msg_->size ());
-
-    uint8_t *message_box = static_cast <uint8_t *> (malloc (mlen));
-    alloc_assert (message_box);
-
-    int rc = crypto_box_afternm (message_box, message_plaintext,
-                                 mlen, message_nonce, cn_precom);
-    zmq_assert (rc == 0);
-
-    rc = msg_->close ();
-    zmq_assert (rc == 0);
-
-    rc = msg_->init_size (16 + mlen - crypto_box_BOXZEROBYTES);
-    zmq_assert (rc == 0);
-
-    uint8_t *message = static_cast <uint8_t *> (msg_->data ());
-
-    memcpy (message, "\x07MESSAGE", 8);
-    memcpy (message + 8, message_nonce + 16, 8);
-    memcpy (message + 16, message_box + crypto_box_BOXZEROBYTES,
-            mlen - crypto_box_BOXZEROBYTES);
-
-    free (message_plaintext);
-    free (message_box);
-
-    cn_nonce++;
-
-    return 0;
 }
 
 int zmq::curve_server_t::decode (msg_t *msg_)
 {
     zmq_assert (state == ready);
-
+    return curve_mechanism_base_t::decode (msg_);
-    int rc = check_basic_command_structure (msg_);
-    if (rc == -1)
-      return -1;
-
-    const size_t size = msg_->size ();
-    const uint8_t *message = static_cast <uint8_t *> (msg_->data ());
-    
-    if (size < 8 || memcmp (message, "\x07MESSAGE", 8)) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_UNEXPECTED_COMMAND);
-        errno = EPROTO;
-        return -1;
-    }
-
-    if (size < 33) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (),
-          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_MESSAGE);
-        errno = EPROTO;
-        return -1;
-    }
-
-    uint8_t message_nonce [crypto_box_NONCEBYTES];
-    memcpy (message_nonce, "CurveZMQMESSAGEC", 16);
-    memcpy (message_nonce + 16, message + 8, 8);
-    uint64_t nonce = get_uint64(message + 8);
-    if (nonce <= cn_peer_nonce) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_INVALID_SEQUENCE);
-        errno = EPROTO;
-        return -1;
-    }
-    cn_peer_nonce = nonce;
-
-    const size_t clen = crypto_box_BOXZEROBYTES + msg_->size () - 16;
-
-    uint8_t *message_plaintext = static_cast <uint8_t *> (malloc (clen));
-    alloc_assert (message_plaintext);
-
-    uint8_t *message_box = static_cast <uint8_t *> (malloc (clen));
-    alloc_assert (message_box);
-
-    memset (message_box, 0, crypto_box_BOXZEROBYTES);
-    memcpy (message_box + crypto_box_BOXZEROBYTES,
-            message + 16, msg_->size () - 16);
-
-    rc = crypto_box_open_afternm (message_plaintext, message_box, clen,
-                                  message_nonce, cn_precom);
-    if (rc == 0) {
-        rc = msg_->close ();
-        zmq_assert (rc == 0);
-
-        rc = msg_->init_size (clen - 1 - crypto_box_ZEROBYTES);
-        zmq_assert (rc == 0);
-
-        const uint8_t flags = message_plaintext [crypto_box_ZEROBYTES];
-        if (flags & 0x01)
-            msg_->set_flags (msg_t::more);
-        if (flags & 0x02)
-            msg_->set_flags (msg_t::command);
-
-        memcpy (msg_->data (),
-                message_plaintext + crypto_box_ZEROBYTES + 1,
-                msg_->size ());
-    }
-    else {
-        // CURVE I : connection key used for MESSAGE is wrong
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (), ZMQ_PROTOCOL_ERROR_ZMTP_CRYPTOGRAPHIC);
-        errno = EPROTO;
-    }
-    free (message_plaintext);
-    free (message_box);
-
-    return rc;
 }
 
 int zmq::curve_server_t::process_hello (msg_t *msg_)

src/curve_server.hpp

@@ -32,34 +32,18 @@
 
 #ifdef ZMQ_HAVE_CURVE
 
-#if defined (ZMQ_USE_TWEETNACL)
+#include "curve_mechanism_base.hpp"
-#   include "tweetnacl.h"
-#elif defined (ZMQ_USE_LIBSODIUM)
-#   include "sodium.h"
-#endif
-
-#if crypto_box_NONCEBYTES != 24 \
-||  crypto_box_PUBLICKEYBYTES != 32 \
-||  crypto_box_SECRETKEYBYTES != 32 \
-||  crypto_box_ZEROBYTES != 32 \
-||  crypto_box_BOXZEROBYTES != 16 \
-||  crypto_secretbox_NONCEBYTES != 24 \
-||  crypto_secretbox_ZEROBYTES != 32 \
-||  crypto_secretbox_BOXZEROBYTES != 16
-#   error "CURVE library not built properly"
-#endif
-
-#include "mechanism.hpp"
 #include "options.hpp"
 #include "zap_client.hpp"
 
 namespace zmq
 {
-
+#ifdef _MSC_VER
-    class msg_t;
+#pragma warning (push)
-    class session_base_t;
+#pragma warning (disable: 4250)
-
+#endif
-    class curve_server_t : public zap_client_common_handshake_t
+    class curve_server_t : public zap_client_common_handshake_t,
+                           public curve_mechanism_base_t
     {
     public:
 
@@ -76,9 +60,6 @@ namespace zmq
 
     private:
 
-        uint64_t cn_nonce;
-        uint64_t cn_peer_nonce;
-
         //  Our secret key (s)
         uint8_t secret_key [crypto_box_SECRETKEYBYTES];
 
@@ -94,9 +75,6 @@ namespace zmq
         //  Key used to produce cookie
         uint8_t cookie_key [crypto_secretbox_KEYBYTES];
 
-        //  Intermediary buffer used to speed up boxing and unboxing.
-        uint8_t cn_precom [crypto_box_BEFORENMBYTES];
-
         int process_hello (msg_t *msg_);
         int produce_welcome (msg_t *msg_);
         int process_initiate (msg_t *msg_);
@@ -105,6 +83,9 @@ namespace zmq
 
         void send_zap_request (const uint8_t *key);
     };
+#ifdef _MSC_VER
+#pragma warning (pop)
+#endif
 
 }
 

src/mechanism.cpp

@@ -282,24 +282,3 @@ bool zmq::mechanism_t::check_socket_type (const std::string& type_) const
     }
     return false;
 }
-
-zmq::mechanism_base_t::mechanism_base_t (session_base_t *const session_,
-                                         const options_t &options_) :
-    mechanism_t (options_),
-    session (session_)
-{
-
-}
-
-int zmq::mechanism_base_t::check_basic_command_structure (msg_t *msg_)
-{
-    if (msg_->size () <= 1 || msg_->size () <= ((uint8_t *) msg_->data ())[0]) {
-        session->get_socket ()->event_handshake_failed_protocol (
-          session->get_endpoint (),
-          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_UNSPECIFIED);
-        errno = EPROTO;
-        return -1;
-    }
-    return 0;
-}
-

src/mechanism.hpp

@@ -147,16 +147,6 @@ namespace zmq
         bool check_socket_type (const std::string& type_) const;
     };
 
-    class mechanism_base_t : public mechanism_t
+}
-    {
-      protected:
-        mechanism_base_t (session_base_t *const session_,
-                          const options_t &options_);
-
-        session_base_t *const session;
-
-        int check_basic_command_structure (msg_t *msg_);
-    };
-    }
 
 #endif

src/mechanism_base.cpp

@@ -0,0 +1,54 @@
+/*
+    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
+
+    This file is part of libzmq, the ZeroMQ core engine in C++.
+
+    libzmq is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    As a special exception, the Contributors give you permission to link
+    this library with independent modules to produce an executable,
+    regardless of the license terms of these independent modules, and to
+    copy and distribute the resulting executable under terms of your choice,
+    provided that you also meet, for each linked independent module, the
+    terms and conditions of the license of that module. An independent
+    module is a module which is not derived from or based on this library.
+    If you modify this library, you must extend this exception to your
+    version of the library.
+
+    libzmq 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 "precompiled.hpp"
+
+#include "mechanism_base.hpp"
+#include "session_base.hpp"
+
+zmq::mechanism_base_t::mechanism_base_t (session_base_t *const session_,
+                                         const options_t &options_) :
+    mechanism_t (options_),
+    session (session_)
+{
+
+}
+
+int zmq::mechanism_base_t::check_basic_command_structure (msg_t *msg_)
+{
+    if (msg_->size () <= 1 || msg_->size () <= ((uint8_t *) msg_->data ())[0]) {
+        session->get_socket ()->event_handshake_failed_protocol (
+          session->get_endpoint (),
+          ZMQ_PROTOCOL_ERROR_ZMTP_MALFORMED_COMMAND_UNSPECIFIED);
+        errno = EPROTO;
+        return -1;
+    }
+    return 0;
+}
+

src/mechanism_base.hpp

@@ -0,0 +1,49 @@
+/*
+    Copyright (c) 2007-2016 Contributors as noted in the AUTHORS file
+
+    This file is part of libzmq, the ZeroMQ core engine in C++.
+
+    libzmq is free software; you can redistribute it and/or modify it under
+    the terms of the GNU Lesser General Public License (LGPL) as published
+    by the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    As a special exception, the Contributors give you permission to link
+    this library with independent modules to produce an executable,
+    regardless of the license terms of these independent modules, and to
+    copy and distribute the resulting executable under terms of your choice,
+    provided that you also meet, for each linked independent module, the
+    terms and conditions of the license of that module. An independent
+    module is a module which is not derived from or based on this library.
+    If you modify this library, you must extend this exception to your
+    version of the library.
+
+    libzmq 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/>.
+*/
+
+#ifndef __ZMQ_MECHANISM_BASE_HPP_INCLUDED__
+#define __ZMQ_MECHANISM_BASE_HPP_INCLUDED__
+
+#include "mechanism.hpp"
+
+namespace zmq
+{
+class mechanism_base_t : public mechanism_t
+{
+  protected:
+    mechanism_base_t (session_base_t *const session_,
+                      const options_t &options_);
+
+    session_base_t *const session;
+
+    int check_basic_command_structure (msg_t *msg_);
+};
+}
+
+#endif

src/plain_client.hpp

@@ -30,7 +30,7 @@
 #ifndef __ZMQ_PLAIN_CLIENT_HPP_INCLUDED__
 #define __ZMQ_PLAIN_CLIENT_HPP_INCLUDED__
 
-#include "mechanism.hpp"
+#include "mechanism_base.hpp"
 #include "options.hpp"
 
 namespace zmq

src/zap_client.hpp

@@ -30,7 +30,7 @@
 #ifndef __ZMQ_ZAP_CLIENT_HPP_INCLUDED__
 #define __ZMQ_ZAP_CLIENT_HPP_INCLUDED__
 
-#include "mechanism.hpp"
+#include "mechanism_base.hpp"
 
 namespace zmq
 {

tests/test_security_curve.cpp

@@ -491,7 +491,8 @@ int connect_exchange_greeting_and_hello_welcome (
     uint8_t welcome[welcome_length + 2];
     recv_all (s, welcome, welcome_length + 2);
     
-    int res = tools.process_welcome (welcome + 2, welcome_length);
+    uint8_t cn_precom [crypto_box_BEFORENMBYTES];
+    int res = tools.process_welcome (welcome + 2, welcome_length, cn_precom);
     assert (res == 0);
 
 #ifdef ZMQ_BUILD_DRAFT_API