Compiling on Windows (MinGW)

[tibotix]

To compile libopaque on windows with MinGW, the following steps had to be done:

• renaming the aux directory to aux_, as AUX is a reserved file/directory name in Windows.
• add a seperate makefile.windows that changes some compiler flags (e.g. -z relro does not exist in MinGW) , changes SOEXT to dll and add a linker flag to link agains -lws2_32 (winsocks2 lib)
• add preprocessor check in opaque.c to conditionally include winsock2.h instead of arpa/inet.h for the htons function

Things that do not compile under Windows are:

• utils/main.c executable, as it uses some specific fcntl() calls that do not exist in windows.

Note that iam not very familiar with the linker options provided by MinGW and which one is responsible for extra security features. However, this is the output of winchecksec against the compiled libopaque.dll lib:

Warn: No load config in the PE
Results for: ./libopaque.dll
Dynamic Base    : "Present"
ASLR            : "Present"
High Entropy VA : "Present"
Force Integrity : "NotPresent"
Isolation       : "Present"
NX              : "Present"
SEH             : "Present"
CFG             : "NotPresent"
RFG             : "NotPresent"
SafeSEH         : "NotApplicable"
GS              : "NotPresent"
Authenticode    : "NotPresent"
.NET            : "NotPresent"

[stef]

awesome. instead of a seperate makefile you can have a look at how we handle different archs/os in a sister projects makefile: https://github.com/stef/libsphinx/blob/master/src/makefile

and maybe call the target mingw instead of windows, maybe someone comes along and adds a visualc port or so...

[stef]

btw the fcntls are used for checking if a filedescriptor is open/exists, if you know a replacement for that in mingw perhaps?

[tibotix]

As far as I know, MinGW has a _fstat function that expects an open file descriptor and some buffer and returns -1 if the file status information could not be obtained and 0 if it could be obtained. maybe this is useful...

[tibotix]

I changed utils/main.c to use the _fstat function. It now compiles under MinGW and runs. However i have not checked the functionality of the WindowsAPI call yet.

[stef]

love it! are you sure you're only 18?

[stef]

btw also added a note to the main readme about your dart binding...

[tibotix]

Ah Perfect , thanks. I also plan to publish the dart bindings on pub.dev btw . And yeah haha I am sure I’m only 18 :) started really early with programming and stuff …