New Windows build instructions using VS.

BUILD-WINDOWS-VisualStudio.md

@@ -0,0 +1,103 @@
+# Windows build using Visual Studio
+
+This document describes how to build on Windows using Visual Studio. Note that only
+32-bit build has been tested and is described here.
+
+## Prerequisites
+
+### Visual Studio
+
+You need Visual Studio 2017.
+
+### CMake
+
+You need CMake, it is best to get the latest version.
+
+### OpenSSL
+
+You don't need this if you only need tun2socks or udpgw (but only for the VPN software).
+
+Install ActivePerl if not already.
+
+Download and extract the OpenSSL source code.
+
+Open a Visual Studio x86 native tools command prompt (found under Programs -> Visual
+Studio 2017) and enter the OpenSSL source code directory. In this terminal, run the
+following commands:
+
+```
+perl Configure VC-WIN32 no-asm --prefix=%cd%\install-dir
+ms\do_ms
+nmake -f ms\ntdll.mak install
+```
+
+### NSS
+
+You don't need this if you only need tun2socks or udpgw (but only for the VPN software).
+
+Install MozillaBuild (https://wiki.mozilla.org/MozillaBuild).
+
+Download and extract the NSS source code that includes NSPR
+(`nss-VERSION-with-nspr-VERSION.tar.gz`).
+
+Copy the file `C:\mozilla-build\start-shell.bat` to
+`C:\mozilla-build\start-shell-fixed.bat`, and in the latter file REMOVE the following
+lines near the beginning:
+
+```
+SET INCLUDE=
+SET LIB=
+IF NOT DEFINED MOZ_NO_RESET_PATH (
+  SET PATH=%SystemRoot%\System32;%SystemRoot%;%SystemRoot%\System32\Wbem
+)
+```
+
+Open a Visual Studio x86 native tools command prompt. In this terminal, first run the
+following command to enter the mozilla-build bash shell:
+
+```
+C:\mozilla-build\start-shell-fixed.bat
+```
+
+Enter the NSS source code directory and run the following commands:
+
+```
+make -C nss nss_build_all OS_TARGET=WINNT BUILD_OPT=1
+cp -r dist/private/. dist/public/. dist/WINNT*.OBJ/include/
+```
+
+## Building BadVPN
+
+Open a Visual Studio x86 native tools command prompt (found under Programs -> Visual
+Studio 2017) and enter the BadVPN source code directory.
+
+If you needed to build OpenSSL and NSS, then specify the paths to the builds of these
+libraries by setting the `CMAKE_PREFIX_PATH` environment variable as shown below;
+replace `<openssl-source-dir>` and `<nss-source-dir>` with the correct paths. For NSS,
+check if the `.OBJ` directory name is correct, if not then adjust that as well.
+
+```
+set CMAKE_PREFIX_PATH=<openssl-source-dir>\install-dir;<nss-source-dir>\dist\WINNT6.2_OPT.OBJ
+```
+
+Run the commands shown below. If you only need tun2socks and udpgw then also add
+the following parameters to first `cmake` command:
+`-DBUILD_NOTHING_BY_DEFAULT=1 -DBUILD_TUN2SOCKS=1 -DBUILD_UDPGW=1`.
+
+```
+mkdir build
+cd build
+cmake .. -G "Visual Studio 15 2017" -DCMAKE_INSTALL_PREFIX=%cd%\..\install-dir
+cmake --build . --config Release --target install
+```
+
+If you did need OpenSSL and NSS, then copy the needed DLL so that the programs will
+be able to find them. You can use the following commands to do this (while still in
+the `build` directory):
+
+```
+copy <openssl-source-dir>\install-dir\bin\libeay32.dll ..\install-dir\bin\
+copy <nss-source-dir>\dist\WINNT6.2_OPT.OBJ\lib\*.dll ..\install-dir\bin\
+```
+
+The build is now complete and is located in `<badvpn-source-dir>\install-dir`.

README.md

@@ -36,17 +36,31 @@ These connections are used for transferring network data (Ethernet frames), and
   - Local peers inside a NAT can communicate directly
   - Relaying as a fallback (needs configuration)
 
-## Documentation
-
-- [NCD] - Introduction to the NCD language.
-- [badvpn] - General description of BadVPN and its features.
-- [Examples] - Quick guide to setting up a working VPN.
-- [badvpn_server], [badvpn_client] - Documentation of individual programs.
-
 ## Requirements
 
 NCD only works on Linux. Tun2socks works on Linux and Windows. The P2P VPN works on Linux, Windows and FreeBSD (not tested often).
 
+## Installation
+
+The build system is based on CMake. On Linux, the following commands can be used to
+build:
+
+```
+cd <badvpn-source-dir>
+mkdir build
+cd build
+cmake .. -DCMAKE_INSTALL_PREFIX=<install-dir>
+make install
+```
+
+If you only need tun2socks or udpgw, then add the following arguments to the `cmake`
+command: `-DBUILD_NOTHING_BY_DEFAULT=1 -DBUILD_TUN2SOCKS=1 -DBUILD_UDPGW=1`.
+Otherwise (if you want the VPN software), you will first need to install the OpenSSL
+and NSS libraries and make sure that CMake can find them.
+
+Windows builds are not provided. You can build from source code using Visual Studio by
+following the instructions in the file `BUILD-WINDOWS-VisualStudio.md`.
+
 ## License
 
 The BSD 3-clause license as shown below applies to most of the code.