How to create self-certified SSL certificate and public/private key files

Introduction

Iguana only supports OpenSSL SSH-2 private keys and certificates in PEM format, these must not be password protected. Iguana accepts the older “Traditional” (or “SSLeay”) PKCS#5 format (as defined in RFC2890) or in the newer PKCS#8 format (as defined in RFC5958).

In order to enable HTTPS support for use with Iguana, you must first generate valid public key/private key certificates. These digital certificates are used to authenticate the sender. Keys are typically generated in pairs, with one being public and the other being private. The private key must be kept secret to ensure security. It is used to encrypt outgoing messages and decrypt incoming messages. A public key is the one that is released to the public. It allows anyone to use it for encrypting messages to be sent to the user, as well as for decrypting messages received from the user.

If you use OpenSSL to generate certificates, the private key will contain public key information, therefore the public key does not have to be generated separately. You will need to have OpenSSL installed on your machine. You can download OpenSSL for Windows or Unix from: http://www.openssl.org.

On Windows you can use the PuTTYgen program to generate public and private keys, however it does not generate certificates. You can download PuTTYgen for Windows: http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html.

In addition to having a public/private key certificate, you must also obtain a certificate file from a certificate authority (CA), such as Verisign, which issues digital certificates for use by other parties. There are many commercial CAs that charge for their services, while other institutions may have their own CAs. To ensure that the web server (with HTTPS support enabled) functions as expected, you can create a self-signed certificate for use during the initial testing phase.

Accepted formats [top]

If you are in hurry (and don’t need explanations), then you can just skip this section.

However if you are having a problem with Iguana not accepting your private key, then you should open the key file in a text editor and check if it matches one of two accepted formats.

Iguana will accept these two PKCS formats:

  • The older “Traditional” (or “SSLeay”) PKCS#5 format for private keys and certificates (as defined in RFC2890) in unencrypted form (= no passphrase).
    These files can be recognized by their specific headers and footers:

  • The newer PKCS#8 format for private keys (as defined in RFC5958), in unencrypted form (= no passphrase).
    These files can be recognized by their specific headers and footers:

Note: Iguana will not accept SSH format defined in RFC4716, even though the format looks similar:

OpenSSL: Create a public/private key file pair [top]

This section shows you how to create a public/private key file using OpenSSL.

To generate a public/private key file on a Windows system:

  1. You will need to have OpenSSL installed.
  2. Create a new directory on your C drive and give it an appropriate name (i.e., Test).
  3. Open a Command Prompt window and go to the new directory. For example:
    C:>cd Test
    
    C:Test>
  4. Type the path of the OpenSSL install directory, followed by the RSA key algorithm. For example:
    C:Test>c:openssl\bin\openssl genrsa -out privkey.pem 4096
    Loading 'screen' into random state - done
    Generating RSA private key, 4096 bit long modulus
    .................................+++
    ...........................................+++
    e is 65537 (0x10001)
  5. Then run this command to split the generated file into separate private and public key files
    C:Test>c:openssl\bin\openssl ssh-keygen -t rsa -b 4096 -f privkey.pem
    

To generate a public/private key file on a POSIX system:

  1. Use the ssh-keygen utility which is included as part of most POSIX systems.
  2. Create a new directory and give it an appropriate name (i.e., Test).
  3. Open a Command Prompt window and go to the new directory. For example:
    cd Test
    
  4. Use the rsa option for ssh-keygen command to create a key:
    ssh-keygen -t rsa -b 4096
    

The public & private key files are saved in the new directory you created earlier. An example of a private key file is shown below:

-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----

You can copy the key from above. This key is to be used for testing purposes only.

Note: In this example, the 4096 parameter to the openssl genrsa command indicates that the generated key is 4096 bits long. A key that is 4096 bits or longer is considered more secure. A shorter key will be less secure, but will require less computation to use.

OpenSSL: Create a certificate [top]

This section shows you how to create a self-signed certificate file using OpenSSL.

Note: Iguana offers support for x509 compatible certificates in pem format, certificates must not be password protected.

To generate a self-signed certificate file on a Windows system:

  1. You will need to have OpenSSL installed.
  2. Open a command prompt window and go to the directory you created earlier for the public/private key file. For example:
    C:>cd Test
    
    C:Test>
  3. Enter the path of the OpenSSL install directory, followed by the self-signed certificate algorithm. For example:
    C:Test>c:openssl\bin\openssl req -new -x509 -key privkey.pem -out cacert.pem -days 1095
  4. Follow the instructions that appear in the screen. For example:
    You are about to be asked to enter information that will be incorporated
    into your certificate request.
    What you are about to enter is what is called a Distinguished Name or a DN.
    There are quite a few fields but you can leave some blank
    For some fields there will be a default value,
    If you enter '.', the field will be left blank.
    -----
    Country Name (2 letter code) [AU]:CA
    State or Province Name (full name) [Some-State]:Ontario
    Locality Name (eg, city) []:Toronto
    Organization Name (eg, company) [Internet Widgits Pty Ltd]:iNTERFACEWARE
    Organizational Unit Name (eg, section) []:
    Common Name (eg, YOUR name) []:
    Email Address []:

To generate a self-signed certificate file on a POSIX system:

  1. You will need to have OpenSSL installed.
  2. Open a command prompt window and go to the directory you created earlier for the public/private key file. For example:
    cd Test
    
  3. Enter the path of the OpenSSL install directory, followed by the self-signed certificate algorithm. For example:
    /<path to openssl>/openssl/bin/openssl req -new -x509 -key privkey.pem -out cacert.pem -days 1095
    
  4. Follow the instructions that appear in the screen. For example:
    You are about to be asked to enter information that will be incorporated
    into your certificate request.
    What you are about to enter is what is called a Distinguished Name or a DN.
    There are quite a few fields but you can leave some blank
    For some fields there will be a default value,
    If you enter '.', the field will be left blank.
    -----
    Country Name (2 letter code) [AU]:CA
    State or Province Name (full name) [Some-State]:Ontario
    Locality Name (eg, city) []:Toronto
    Organization Name (eg, company) [Internet Widgits Pty Ltd]:iNTERFACEWARE
    Organizational Unit Name (eg, section) []:
    Common Name (eg, YOUR name) []:
    Email Address []:

The self-signed certificate file is created and saved in the directory you specified earlier. An example of the certificate format is shown below:

-----BEGIN CERTIFICATE-----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-----END CERTIFICATE-----

You can copy the certificate from above. This certificate is to be used for testing purposes only.

Note: Remember that this newly created certificate file should be used for test purposes only. Normally, you would need to create a certificate request and send it to a certificate authority (CA). The CA would then sign the certificate and give it back to you upon payment, thus providing you with authentication according to their outlined policies.

PuTTYgen: Create a public/private key file pair [top]

To generate a public/private key file:

  1. Open puttygen.exe by double clicking on it.
    Note: It is a standalone executable and will run from anywhere.
  2. Click the Generate button, and move the mouse around to generate randomness.
    Note: PuTTYgen defaults to the desired SSH-2 RSA key.
  3. Use Conversions>Export OpenSSL key to export the private key as a “Traditional fortmat” OpenSSL SSH-2 file:

    Note: The “ssh.com” export format  is not compatible with Iguana.
  4. Copy the OpenSSH format key for use with Github, Bitbucket and other Git hosts:

    Note: Make sure to scroll down to ensure you get the whole key.

 

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