Implement generic interface for bignum and diffie-hellman

Implementation of a generic wrap interface for bignum and diffie-hellman
based upon Damien's wrap code in openssh-openbsd.  This commit adds the
generic interface along with the backing code for openssl, cng, and cng
with an openssl fallback.  Currently, openssl is the only provider for
bignum and the diffie-hellman generic interface is only for static and
negotiated oakley groups..

Author: dkulwin

contrib/win32/openssh/libssh.vcxproj

@@ -258,6 +258,13 @@
     <ClCompile Include="$(OpenSSH-Src-Path)uuencode.c" />
     <ClCompile Include="$(OpenSSH-Src-Path)verify.c" />
     <ClCompile Include="$(OpenSSH-Src-Path)xmalloc.c" />
+    <ClCompile Include="$(OpenSSH-Src-Path)openssl-bn.c" />
+    <ClCompile Include="$(OpenSSH-Src-Path)openssl-dh.c">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+    </ClCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="$(OpenSSH-Src-Path)crypto-wrap.h" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

contrib/win32/openssh/libssh.vcxproj.filters

@@ -288,5 +288,16 @@
     <ClCompile Include="$(OpenSSH-Src-Path)xmalloc.c">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\..\openssl-dh.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+    <ClCompile Include="..\..\..\openssl-bn.c">
+      <Filter>Source Files</Filter>
+    </ClCompile>
+  </ItemGroup>
+  <ItemGroup>
+    <ClInclude Include="..\..\..\crypto-wrap.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
 </Project>

contrib/win32/openssh/win32compat.vcxproj

@@ -159,11 +159,13 @@
     <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\tncon.c" />
     <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\tnnet.c" />
     <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\win32auth.c" />
-    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kex.c" />
-    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kexdhc.c" />
-    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kexdhs.c" />
-    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kexgexc.c" />
-    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kexgexs.c" />
+    <ClCompile Include="..\win32compat\cng_dh.c">
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
+      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
+    </ClCompile>
+    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_openssl_dh.c" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\ansiprsr.h" />

contrib/win32/openssh/win32compat.vcxproj.filters

@@ -81,19 +81,10 @@
     <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\win32auth.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="..\win32compat\cng_kex.c">
+    <ClCompile Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kex.c">
       <Filter>Source Files</Filter>
     </ClCompile>
-    <ClCompile Include="..\win32compat\cng_kexdhc.c">
-      <Filter>Source Files</Filter>
-    </ClCompile>
-    <ClCompile Include="..\win32compat\cng_kexdhs.c">
-      <Filter>Source Files</Filter>
-    </ClCompile>
-    <ClCompile Include="..\win32compat\cng_kexgexc.c">
-      <Filter>Source Files</Filter>
-    </ClCompile>
-    <ClCompile Include="..\win32compat\cng_kexgexs.c">
+    <ClCompile Include="..\win32compat\cng_openssl_dh.c">
       <Filter>Source Files</Filter>
     </ClCompile>
   </ItemGroup>
@@ -140,7 +131,10 @@
     <ClInclude Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\win32auth.h">
       <Filter>Header Files</Filter>
     </ClInclude>
-    <ClInclude Include="..\win32compat\cng_kex.h">
+    <ClInclude Include="$(OpenSSH-Src-Path)\contrib\win32\win32compat\cng_kex.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
+    <ClInclude Include="..\win32compat\cng-wrap.h">
       <Filter>Header Files</Filter>
     </ClInclude>
   </ItemGroup>