i have a .PEM file that includes public key and a private key for SSL data transfer like this:
-----BEGIN RSA PRIVATE KEY-----
private key data
-----END RSA PRIVATE KEY-----
-----BEGIN CERTIFICATE-----
public key data
-----END CERTIFICATE-----
when i want to load the .PEM file by the following code:
X509Certificate2 xx = new X509Certificate2("c:\\myKey.pem");
i get an exception that says: "Cannot find the requested object." , with full stack:
System.Security.Cryptography.CryptographicException was unhandled
Message=Cannot find the requested object.
Source=mscorlib
StackTrace:
at System.Security.Cryptography.CryptographicException.ThrowCryptographicException(Int32 hr)
at System.Security.Cryptography.X509Certificates.X509Utils._QueryCertFileType(String fileName)
at System.Security.Cryptography.X509Certificates.X509Certificate.LoadCertificateFromFile(String fileName, Object password, X509KeyStorageFlags keyStorageFlags)
at System.Security.Cryptography.X509Certificates.X509Certificate..ctor(String fileName)
at System.Security.Cryptography.X509Certificates.X509Certificate2..ctor(String fileName)
at DLLTest.SSL_Test.test() in E:\Projects\DLLTest\DLLTest\SSL_Test.cs:line 165
at DLLTest.SSL_Test.Run() in E:\Projects\DLLTest\DLLTest\SSL_Test.cs:line 21
at DLLTest.Program.Main(String[] args) in E:\Projects\DLLTest\DLLTest\Program.cs:line 21
at System.AppDomain._nExecuteAssembly(RuntimeAssembly assembly, String[] args)
at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.ThreadHelper.ThreadStart()
InnerException:
if i swap place of private key section and public key section, the code works and load data, and i can get just public key info from the object, eg. IssuerName, and its HasPrivateKey is false. why? am i misunderstood and doing wrong something?
There's an article on the Code Project that has all the code you need to do this. It's just a couple of classes so it's a light-weight solution.
To get the bytes for either a certificate or a key from the PEM file the following method will work, regardless of the order of the key and certificate in the file.
byte[] GetBytesFromPEM( string pemString, string section )
{
var header = String.Format("-----BEGIN {0}-----", section);
var footer = String.Format("-----END {0}-----", section);
var start= pemString.IndexOf(header, StringComparison.Ordinal);
if( start < 0 )
return null;
start += header.Length;
var end = pemString.IndexOf(footer, start, StringComparison.Ordinal) - start;
if( end < 0 )
return null;
return Convert.FromBase64String( pemString.Substring( start, end ) );
}
Load the PEM file into a string and call the method above to get the bytes that represent the certificate. Next you pass the obtained bytes to the constructor of an X509Certificate2 :
var pem = System.IO.File.ReadAllText( "c:\\myKey.pem" );
byte[] certBuffer = GetBytesFromPEM( pem, "CERTIFICATE" );
var certificate = new X509Certificate2( certBuffer );
Loading the (RSA) private key from the PEM file is a bit more complicated but you'll find support for that in the above mentioned article as well using the Crypto.DecodeRsaPrivateKey
method.