How to unlock your Huawei E173 dongle

I had a Huawei E173 dongle locked to Dialog and was able to unlock it successfully.

If that interests you, keep on reading... 

Download the following stuff: 

1. Code generator 

2. New firmware installer 

3. Unbranded dashboard (optional)

Steps: 

1. Run the code generator and enter your IMEI. Note the unlock code. 

2. Run the new firmware installer and input the unlock code when prompted. 

3. Optionally install unbranded dashboard software. (Dialog dashboard works with other SIMs!) 

Enjoy!!!

C#: Exploring OpenSSL.NET

I am currently involved in a project module which involves a bit of cryptography. The basic requirements are:

• Generating RSA key pair
• Creating a CSR file
• Generating a Checksum
• Encrypting with private key
• Reading a certificate file
• Verifying a signature 

So while I was googling for hints, I came across this free library called OpenSSL.NET which looked promising. Find the code below which I use to accomplish the above tasks.

This function generates an RSA key pair and returns a CryptoKey object. The length of the keys are hard-coded to be 2048.

        /// <summary>
        /// Generates a 2048 bit RSA key pair.
        /// </summary>
        /// <returns>The key container</returns>
        public static CryptoKey GenerateRsaKeyPair()
        {
            using(var rsa = new RSA())
            {
                rsa.GenerateKeys(2048, 0x10021, null, null);
                return new CryptoKey(rsa);
            }
        }

The following function takes in a RSA key and creates a CSR file. I have used a DTO to pass in the additional details needed for the CSR generation.

        /// <summary>
        /// Generates a CSR file content according to the details given.
        /// </summary>
        /// <param name="csr">CSR details</param>
        /// /// <param name="key">RSA key</param>
        /// <returns>The CSR file content</returns>
        public static string GenerateCsr(CsrProperties csr, CryptoKey key)
        {
            using (var subject = new X509Name
                              {
                                  Country = csr.CountryName,
                                  Organization = csr.OrganizationName,
                                  OrganizationUnit = csr.OrganizationalUnitName,
                                  SerialNumber = csr.SerialNumber,
                                  Common = csr.CommonName
                              })
            {
                using (var req = new X509Request(0, subject, key))
                {
                    return req.PEM;
                }
            }
        }

For Checksum generation, which is also knowing as generating the hash, I used the following code. The algorithm was SHA256.

        /// <summary>
        /// Generates checksum using SHA256 algorithm.
        /// </summary>
        /// <param name="payLoad">Data to be used for hashing</param>
        /// <returns>The hash</returns>
        public static byte[] GenerateChecksum(byte[] payLoad)
        {
            using (var algo = new SHA256Managed())
            {
                return algo.ComputeHash(payLoad);
            }
        }

To do RSA encryption, I used .NET's native cryptography methods.

        /// <summary>
        /// Encrypts the data using RSA key.
        /// </summary>
        /// <param name="payLoad">Data to be encrypted</param>
        /// <param name="key">RSA key</param>
        /// <returns>The encrypted data</returns>
        public static byte[] Encrypt(byte[] payLoad, CryptoKey key)
        {
            using (var rsa = key.GetRSA())
            {
                return rsa.PrivateEncrypt(payLoad, RSA.Padding.PKCS1);
            }
        }

Well that's about it for now. I will update this with more functions as I move on.

Cheers!