first commit

Author: ilmanzo

.gitignore

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+.dub
+docs.json
+__dummy.html
+docs/
+/gauthenticator
+gauthenticator.so
+gauthenticator.dylib
+gauthenticator.dll
+gauthenticator.a
+gauthenticator.lib
+gauthenticator-test-*
+*.exe
+*.o
+*.obj
+*.lst
+secret.pem

dub.sdl

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+name "gauthenticator"
+description "Act as google authenticator device"
+authors "Andrea Manzini"
+copyright "Copyright © 2020, Andrea Manzini"
+license "mit"
+targetType "library"
+

dub.selections.json

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+{
+	"fileVersion": 1,
+	"versions": {
+	}
+}

readme.md

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+## Google Authenticator
+A small D program to generate the google authenticator code.
+
+inspired from https://github.com/tilaklodha/google-authenticator
+
+- Install D Language https://dlang.org/ 
+- Install Dub package manager 
+    - On OSX run `brew install dub`.
+    - Follow instructions on https://code.dlang.org/ for other OSes.
+
+- Provide your 16-digit secret token in secrets.pem file
+
+The auth code works on the secret token and the current time. The time on your local machine should be in sync according to NTP.
+
+- Run `sudo ntpdate time.nist.gov` to sync time
+- Run `rdmd example\runme.d`.
+

source/base32_test.d

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+module base32_test;
+
+import std.stdio;
+
+
+public int[] base32decode(const string message)
+    {
+        int buffer = 0;
+        int bitsLeft = 0;
+        int[] result;
+        for (int i = 0; i < message.length; i++)
+        {
+            int ch = message[i];
+            writeln(ch);
+            if (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n' || ch == '-')
+            {
+                continue;
+            }
+            buffer <<= 5;
+
+            // Deal with commonly mistyped characters
+            if (ch == '0')
+            {
+                ch = 'O';
+            }
+            else if (ch == '1')
+            {
+                ch = 'L';
+            }
+            else if (ch == '8')
+            {
+                ch = 'B';
+            }
+
+            // Look up one base32 digit
+            if ((ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z'))
+            {
+                ch = (ch & 0x1F) - 1;
+            }
+            else if (ch >= '2' && ch <= '7')
+            {
+                ch -= '2' - 26;
+            }
+
+            buffer |= ch;
+            bitsLeft += 5;
+            if (bitsLeft >= 8)
+            {
+                result ~= (buffer >> (bitsLeft - 8));
+                bitsLeft -= 8;
+            }
+
+        }
+        return result;
+
+    }
+
+void main() {
+   writeln("ciao");
+
+    
+    auto expected = cast(int[]) "FOOBAR";
+    writeln(base32decode("IZHU6QSBKIFA===="));
+    writeln(expected);
+}

source/gauthenticator.d

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+/+
+MIT License
+Copyright (c) 2020 Andrea Manzini
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
++/
+
+module gauthenticator;
+
+import std.stdio;
+
+class GAuthenticator
+{
+
+    // HMAC-based One Time Password(HOTP)
+    public string getHOTPToken(const string secret, const ulong interval)
+    {
+        /*
+        auto key=base32decode(secret);
+        hash = HMAC-SHA1(key)
+        offset = last nibble of hash
+        truncatedHash := hash[offset..offset+3]  //4 bytes starting at the offset
+        Set the first bit of truncatedHash to zero  //remove the most significant bit
+        code := truncatedHash mod 1000000
+        pad code with 0 from the left until length of code is 6
+        return code */
+
+        return "000000";
+    }
+
+    //Time-based One Time Password(TOTP)
+    public string getTOTPToken(const string secret)
+    {
+        //The TOTP token is just a HOTP token seeded with every 30 seconds.
+        import std.datetime : Clock;
+
+        immutable ulong interval = Clock.currTime().toUnixTime() / 30;
+        return getHOTPToken(secret, interval);
+    }
+
+    //RFC 4648
+    public int[] base32decode(const string message)
+    {
+        int buffer = 0;
+        int bitsLeft = 0;
+        int[] result;
+        for (int i = 0; i < message.length; i++)
+        {
+            int ch = message[i];
+            writeln(ch);
+            if (ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n' || ch == '-')
+            {
+                continue;
+            }
+            buffer <<= 5;
+
+            // Deal with commonly mistyped characters
+            if (ch == '0')
+            {
+                ch = 'O';
+            }
+            else if (ch == '1')
+            {
+                ch = 'L';
+            }
+            else if (ch == '8')
+            {
+                ch = 'B';
+            }
+
+            // Look up one base32 digit
+            if ((ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z'))
+            {
+                ch = (ch & 0x1F) - 1;
+            }
+            else if (ch >= '2' && ch <= '7')
+            {
+                ch -= '2' - 26;
+            }
+
+            buffer |= ch;
+            bitsLeft += 5;
+            if (bitsLeft >= 8)
+            {
+                result ~= (buffer >> (bitsLeft - 8));
+                bitsLeft -= 8;
+            }
+
+        }
+        return result;
+
+    }
+
+    unittest
+    {
+        const base32 = "gr6d 5br7 25s6 vnck v4vl hlao re======";
+
+    }
+
+    /*
+    unittest
+    {
+        auto ga = new GAuthenticator;
+        auto secret = "dummySECRETdummy";
+        auto interval = ulong(50780342);
+        auto otp = "971294";
+        assert(otp == ga.getHOTPToken(secret, interval));
+    }
+*/
+
+}
+
+unittest
+{
+    writeln("ciao");
+
+    auto ga = new GAuthenticator();
+    auto expected = cast(int[]) "FOOBAR";
+    writeln(ga.base32decode("IZHU6QSBKIFA===="));
+    writeln(expected);
+}