learncrypto/source/actions.d

module actions;

import std.stdio : File, stdin, stdout, writeln;
import std.base64 : Base64;
import std.random : Random, uniform;
import std.algorithm : joiner;

import cipher;

public:

enum chunkSize = 4096;

enum string randomDeviceName = "/dev/random";

void encrypt(string keyFileName, Cipher cipher, bool armor)
{
    auto key = loadKey(keyFileName, armor);
    ubyte[8] nonce;
    if (armor)
    {
        ubyte[] buf;
        foreach (b; stdin.byChunk(chunkSize).joiner.cipherFunction(key, nonce, cipher))
        {
            buf ~= [b];
            if (buf.length == 57)
            {
                stdout.writeln(Base64.encode(buf));
                buf = [];
            }
        }
        if (buf !is null)
            stdout.writeln(Base64.encode(buf));
    }
    else
    {
        foreach (b; stdin.byChunk(chunkSize).joiner.cipherFunction(key, nonce, cipher))
            stdout.rawWrite([b]);
    }
}

void decrypt(string keyFileName, Cipher cipher, bool armor)
{
    auto key = loadKey(keyFileName, armor);
    ubyte[8] nonce;
    if (armor)
    {
        ubyte[] buf;
        foreach (b; Base64.decoder(stdin.byLine).joiner.cipherFunction(key, nonce, cipher))
        {
            stdout.rawWrite([b]);
        }
    }
    else
    {
        foreach (b; stdin.byChunk(chunkSize).joiner.cipherFunction(key, nonce, cipher))
            stdout.rawWrite([b]);
    }
}

void generateKey(bool armor)
{
    auto rng = Random();
    auto randomDevice = File(randomDeviceName, "r");
    scope (exit)
        randomDevice.close();
    uint[1] seed;
    randomDevice.rawRead(seed);
    rng.seed(seed[0]);

    ubyte[32] key;
    foreach (ref b; key)
        b = uniform!ubyte(rng);

    if (armor)
    {
        writeln(Base64.encode(key));
    }
    else
    {
        stdout.rawWrite(key);
    }
}

private:

ubyte[32] loadKey(string filename, bool armor)
{
    auto keyFile = File(filename, "r");
    scope (exit)
        keyFile.close();
    ubyte[32] key;
    if (armor)
    {
        ubyte[] tempKey;
        foreach (line; keyFile.byLine)
            tempKey ~= Base64.decode(line);
        key = tempKey;
    }
    else
    {
        keyFile.rawRead(key);
    }
    return key;
}