nim-crypto

Travis/Build Status, Branch=jenkins  

Simple Crypto Session Tool for C and NIM

This repository is an excerpt from my PAN scanner where I needed a small encryption tool for safely storing journal data. For the PAN scanner, encrypted journals are produced on-site, then transported to a safe site for decryption and further processing.

This library supports

• Create public/private key pairs for encrypting messages.
• Encrypt or decrypt a data stream (aka messages).
• Produce a linkable library to be accessed by a C program.
• Use code as NIM source code library.

Development State

• Supported and tested auto-configure platforms for C and NIM:
  • Linux64: native and Linux32
  • Linux64/MinGW: Win32/64
  • MinGW32/MSys, MinGW32/MSys + gcc64
• On-the-fly NIM compilation (within repository):
  • Linux, MinGW32/MSys (will ignore gcc64)
• Nimble (NIM package manager)
  • TODO

Quick Compilation On Linux

• NIM version 0.16 or newer must be installed
  • Debian/Linux 9.0 (stretch) provides it with APT,
  • Ubuntu 16.04/Xenial provides NIM with APT but was too old at the time of writing this README file.
  • See NIM Installation Instructions for a generic installation.
• A decent C compiler (e.c. gcc) and binutils are needed. This is normally available with NIM because it relies on them.

Download/clone nim-crypto and enter the root directory. Then type

   make -f Makefile.simple

or

   make -f Makefile.simple mingw

where the latter one might be needed on a Windows/MinGW set up. This will produce a binary command file src/cwrap which can be run as

   ./src/cwrap

It will perform some simple key generation and encryption. You are invited to analyse the files

src/Makefile.simple   -- see the BUILD recipe
src/main.c   -- run code instuctions in main()
src/session.nim   -- link library interface

For clean up run

  make -f Makefile.simple clean

Auto-configure

This repository comes with a full auto-configure suite. It also supports a local installation of the latest and greatest NIM compiler inside the repository.

Prerequisites

The auto-configure tools need to be bootstrapped. Once bootstrapped, the helper tools listed below are not necessary anymore.

Bootstrap Helper Tools

The following tools must be installed for bootstrap:

• autoconf 2.68 or newer
• automake 1.13 or newer
• libtool 2.4 or newer
• git 2.10 or newer

Additional Requirements, OS Dependent

Some platforms need extra consideration. The following binaries should be accessible from the command line:

• Command realpath on MSYS/MinGW (just include WinGIT binaries in PATH)
• Command hg on Linux (part of Mercurial, needed for NIMBLE)

C Complier

If a NIM compiler is installed already, the following tools will be available by default.

• Make (e.g. GNU make)
• Gcc (others C compilers might do as well) and the compiler (e.g. binutils) tool-chain.
• Optionally, MinGW on Linux for X-compiling.

Bootstrapping

Download/clone the nim-crypto project from GitHUB and enter its root directory. All bootstrapping commands are bundled into a single make command script called Build. It is accessible in the project root directory. A help page is printed if called without arguments as in

  ./Build

This command script expects the make command installed as /usr/bin/make. You need to edit the first line of this script accordingly if this is not the case (or run it as "make -f Build <args..>" instead).

Optional: Local NIM Installation

Unless a NIM compiler is installed, it can be done locally within the nim-crypto progect tree with the command:

 ./Build nim

This local compiler will also be used parallel to an existing system wide NIM installation.

Bootstrap Configure Script

Run

 ./Build config

Reset All to Original State

For undoing the bootstrap and resetting the repository run

 ./Build clobber

Configuring, Compiling, and Testing

After bootstrapping the configure script run

 ./configure
 make

for making a statically linked binary src/cwraps and probably a dynamically linked one src/cwrapd. Just run them to find out how the encryption works. Note that the dynamically linked binary src/cwrapd is often a wrapper that calls src/.libs/cwrapd. Use

 ldd src/cwraps
 ldd src/.libs/cwrapd

to inspect the dynamic linkages. Run

 make help

for other make commands. Running unit tests on the sources is done with

 make check

As mention earlier, you are invited to analyse the code files

src/main.c   -- run code instuctions in main()
src/session.nim   -- link library interface

Cross Compiling

Bootstrap and configuration can be done with a single Build command. Currently, the following configurations have been tested on Linux64

i386, amd64   -- native variants
win32, win64   -- MinGW cross compiling

For instance, to compile for a 32 bit Windows platform on Linux64 run

 ./Build win32

or

 ./Build win32-debug

This expects that the corresponding MinGW compiler and tool-chain are available. The resulting binary might be tested on Linux with wine as in

 wine src/cwraps.exe

Windows Architectures

This repository compiles on MinGW32/MSys (tested on Windows 7). Optionally, for 64bit systems a gcc64 bit compiler might be used (e.g. tdm64). It will work if the command path has precedence in the PATH environment variable. For gcc64 related build use

./Build mgw32

or

./Build mgw64

for bootstrapping (or alternatively the targets mgw32-debug or mgw64-debug). Otherwise

./Build native

(or the target native-debug) must be used.

-- jordan