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digitalmars.D.learn - Public private key encryption using existing key in dlang

Hi All,

I have tried encrypting a message using public key and sending 
message to client, who decrypts using private key. I have tried 
with openssl d package. Below is my code. However it always fails 
in creating the context and exits by throwing exception. Key that 
i am using is RSA key.

Please help me on this. I have also tried secured and crypto 
packages, but i see crash in these packages also.

import std.array;
import std.string;
import std.algorithm;
import std.stdio;

import core.cpuid;
import core.memory;
import deimos.openssl.evp;
import deimos.openssl.rand;
import deimos.openssl.pem;
import deimos.openssl.bio;
import deimos.openssl.rsa;
import deimos.openssl.engine;

ubyte[] encrypt(const ubyte[] inMessage, EVP_PKEY* keypair)
{
     ENGINE* eng = null; // Use default RSA implementation
     ubyte* out2;
     const ubyte* in2 = inMessage.ptr;
     size_t outlen;
     size_t inlen = inMessage.length;

     auto ctx = EVP_PKEY_CTX_new(keypair, eng);
     if (ctx == null)
     {
         throw new Exception("EVP_PKEY_CTX_new.");
     }
     scope (exit)
     {
         if (ctx !is null)
         {
             EVP_PKEY_CTX_free(ctx);
         }
     }

     if (EVP_PKEY_encrypt_init(ctx) <= 0)
     {
         if (!ctx)
         {
             throw new Exception("EVP_PKEY_CTX_new.");
         }
     }
     scope (exit)
     {
         if (ctx !is null)
         {
             EVP_PKEY_CTX_free(ctx);
         }
     }

     if (EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_OAEP_PADDING) 
<= 0)
     {
         throw new Exception("EVP_PKEY_CTX_set_rsa_padding 
failed.");
     }

     if (EVP_PKEY_encrypt(ctx, null, &outlen, in2, inlen) <= 0)
     {
         throw new Exception("EVP_PKEY_encrypt failed.");
     }

     out2 = cast(ubyte*) GC.malloc(outlen);
     if (out2 == null)
     {
         throw new Exception("Malloc failed.");
     }

     if (EVP_PKEY_encrypt(ctx, out2, &outlen, in2, inlen) <= 0)
     {
         throw new Exception("EVP_PKEY_encrypt failed.");
     }

     return (out2)[0 .. outlen];
}

void main()
{
     const(ubyte)[] message = cast(const(ubyte)[]) "Hello, this is 
a binary message!";
     import core.stdc.stdlib : calloc, free;
     import std.base64;
     auto keyStr = 
"AAACANhbLxG1cezzbb/NsLQQSFseuOSKe2x7xcjuJmiiBC6tlbhT0RV6Y9Zad0tMp3OvS7etq0XRmeKK2QcP6gcqsVnOEX9qtPJMcGoyZxNo7nwU7DEyu9qEBhKMcI+jtRHEqcD0hGHgQg/KJ0bZsIFikKdezDSXQz8uVaJeypwkFChN
     auto keyBytes = Base64.decode(keyStr);
     // auto keyBytes = cast(ubyte[]) keyStr;

     auto bio = BIO_new_mem_buf(keyBytes.ptr, cast(int) 
keyBytes.length);
     auto keypair = PEM_read_bio_PUBKEY(bio, null, null, null);
     // auto rsaKey = PEM_read_bio_RSAPrivateKey(bio, null, null, 
null);

     BIO_free_all(bio);

     encrypt(message, keypair);
}
Feb 05