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How to connect with privateKey and certificate in Rebex

I have the ssh command:
$ssh -i cert.pub -i private_rsa user#host.net
I'm using Rebex.Net.Ssh and I'd like to know how call Login method with Certificate (cert.pub) and PrivateKey (private_rsa), just like command above.
This is possible?
I currently have this code:
ssh.Login(userName, password, new SshPrivateKey(keyPath, keyPassphase))
Best regards!

recreate a certificate with the same credentials with makecert

I have a question, I have created my own certificate with this command :
1) makecert -r -pe -n "CN=MyTest" -sky exchange -sv MyTest.pvk MyTest.cer
2) pvk2pfx -pvk MyTest.pvk -spc MyTest.cer -pfx MyTest.pfx
So I have created a simple console application for crypt an decrypt text with this certificate, all work fine... example:
1) Crypt from text "1" I get "RLSym/wwReReo3GMM27ueIcMFRWHAB1AELnFVERnYuMbjBJi0QrW+oV2ADdJQ8VoZlShun0="
2) Decrypt from "RLSym/wwReReo3GMM27ueIcMFRWHAB1AELnFVERnYuMbjBJi0QrW+oV2ADdJQ8VoZlShun0="
I get "1".
Now I ricreate the certificate with the same command and password and use new one, when I try to Decrypt text create with The first certificate I receive an error, why? It is not possible to ricreate the certificate with the same credential and option if I lose the first one certificate? all my data saved on database is lost?
Thx.

Why does makecert not make a *valid* certificate?

I want to create an X509 certificate for testing purposes. This certificate has to be shared by 3 developers on their local machines (i.e. all share the same certificate so we can use the same thumbprint).
So the private key in this certificate has to be exportable.
I create a certificate with the following command:
makecert -r -pe -n "CN=mytestsite.local" -b 01/01/2000 -e 01/01/2036 -ss my -sr localMachine -sky exchange localhost.cer
This certificate works fine, but the trouble is that the isValid argument has to be false when calling Certificates.Find...
var store = new X509Store(StoreName.My, StoreLocation.LocalMachine);
store.Open(OpenFlags.ReadOnly);
var cert = store.Certificates.Find(
X509FindType.FindByThumbprint,
Config.PdfCertificateThumbprint,
false //********************* This has to be false.
).OfType<X509Certificate>().FirstOrDefault();
As soon as I set that IsValid property to True, my certificate is no longer returned by the Find method. Why would makecert generate an "invalid" certificate? Or how do I figure out why the certificate is deemed invalid?

Well, it's because it's not issued by a "Trusted Certificate Authority" like the "real" ssl certificates used on the internet. (for example issued by VeriSign)
What you can do locally to work is to add the certificate manually in the Trusted Certificates for your user and/or local machine. But this procedure must be done for everyone using it until you will obtain a valid SSL certificate issued by a CA (certificate authority).
But your question points to the scenario where it's for dev purposes only so what you can do is either manually add the certificate to Trusted or you can override the certificate validation mechanism in .Net and write code that will consider your certificate valid.

You might want to experiment with the following setting that can be used in client config to bypass the certificate validation process:
<serviceCertificate>
<authentication certificateValidationMode="None"
revocationMode="NoCheck" />
</serviceCertificate>

Where do I get an x509 certificate from?

I'm currently trying to create a chat based on the SslStream class.
I was going through that msdn link: click here
I realized that I need to get an X509Certificate to establish that task. But I really don't know how can I get one? I know that there are ones who cost money, but there aren't free ones available?
P.S: I'm coming here after doing some search in google about that subject but haven't found any helpfull infomation.
So my question is: Where can I get an x509 certificate?
Thank you.

You can create certificates with the makecert tool.
Or, if your're only interested in encrypting the traffic, without signing it, and you control the client and the server, just use a CryptoStream.

You can generate your own, and sign it yourself, using openssl, though keep in mind if the client tries to verify it, and by client I usually mean the browser, since this is their most common use, though not the only one, they won't be able to.
I know that there are ones who cost money, but there aren't free ones available?
Basically what you are paying for is for a CA, certificate authority to sign it, as such when clients go and verify who you are with with CA it'll pass.
openssl: http://www.openssl.org/
This is the command I ussually use openssl req -x509 -nodes -days 365 -newkey rsa:2048 -keyout server.key -out server.pem
server.pem is your certificate and server.key is your private key.
Giving that you probably already have .NET SDK installed maybe makecert is a better/eassier approach since you would need to build openssl.
Stil I went to their docs and I couldn't find how to set the key size, though apparently the default is 1028 and I think using RSA , but I did find this:
makecert -pe -ss MY -$ individual -n "CN=your name here" -len 2048 -r
from MakeCert - Is it possible to change the key size? to http://www.mazecomputer.com/sxs/help/shared.htm
openssl supports many types not just RSA but maybe you don't need them.

These guys http://www.cacert.org/ have been giving away free certificates for years.

Read through this for clarity. You can sign your public key using Symantec's Verisign service. It is definitely not cheap. For testing, you can make your own certificate using a dummy CA.

SSLStream example - how do I get certificates that work?

I'm using the SSLStream example from msdn here. The client code "seems" to work fine, as I can connect to google and it at least gets past authentication, but the server doesn't.
From the comments from the msdn page, I used the procedure on this page to generate my own private key, but it just doesn't work. I get an exception of System.NotSupportedException: The server mode SSL must use a certificate with the associated private key. So I'm pretty sure whatever I'm doing is wrong.
So my question is simple: how do I get/generate keys that will work for my own little example program from msdn? It can be self-signed, whatever, but I'm too new to SSL to even know what exactly I need. All I want to do is to run the example as-given, except for specifying my own certificates for my local server. And it'd be great to know what I'd have to install on my 2nd machine if I just want to communicate between the two of them too (so it's not a 100% localhost example).
Personally I see this as a flaw in the example document. It should say "to run this, you need to do A, B, C, etc," but it doesn't.

You can get the example to work even with self-signed certificates. I've extracted the commands from the makecert tutorial that you're using with minor modifications:
makecert -sv RootCATest.pvk -r -n "CN=FakeServerName" RootCATest.cer
makecert -ic RootCATest.cer -iv RootCATest.pvk -n "CN=FakeServerName" -sv TempCert.pvk -pe -sky exchange TempCert.cer
cert2spc TempCert.cer TempCert.spc
pvkimprt -pfx TempCert.spc TempCert.pvk
makecert and cert2psc can be found in your Microsoft SDKs\Window\v7.0A\Bin folder.
The pvkImport.exe installer can be downloaded here (Provided by #Jospeph and VirusTotal verified). This used to be downloadable from the Microsoft Site, but they have since taken it down. Alternatively, #Dweeberly pointed us to a new Microsoft-provided replacement, pvk2pfx.
For this next step make sure that you select to EXPORT the private key when the dialog from pvkimprt comes up:
pvkimprt -pfx TempCert.spc TempCert.pvk
pvkimprt will prompt you for a password when you elect to include the private key. You will need to provide this password later when you import the generated .pfx file into the personal store of your server machine
Next, import RootCATest.cer into your Computer store's Trusted Root Certification Authorities (on both the server and client). Notice that the certificate is issued to FakeServerName. This must match the server name that the SslTcpClient expects: sslStream.AuthenticateAsClient(serverName), where serverName is the value of the second argument passed to SslTcpClient.exe.
When your client connects, the server presents a certificate that tells the client "I'm FakeServerName". The client will accept this claim if the client machine trusts the CA that issued the certificate, which is achieved by importing RootCATest.cer into the client's Trusted Root Certification Authorities.
Finally, you need to import the private key that the server is going to use into the server machine's Personal store. This step is important because it addresses The server mode SSL must use a certificate with the associated private key.. This is achieved by importing the .pfx file that you generated earlier. Make sure that you change the file type filter to "all files" so that you can see the .pfx file that you generated:
The sample code provided by MSDN uses port 443 (which is the standard ssl port). Since I created console applications, I changed the port used by the sample classes to 8080:
SslTcpServer:
TcpListener listener = new TcpListener(IPAddress.Any, 8080);
SslTcpClient:
TcpClient client = new TcpClient(machineName, 8080);
Here's the output:
you would launch your server like this:
SslTcpServer.exe TempCert.cer
from the client, you would connect like this:
SslTcpClient.exe <ip to your server> FakeServerName

generate your certificate using this command:
makecert -r -pe -n "CN=localhost" -m 12 -sky CertSubject -ss my serverCert.cer
and then from client connect to the server like this (assuming we are using MSDN example you mentioned):
SslTcpClient.RunClient ("localhost", "CertSubject");
you will get validation errors in ValidateServerCertificate() call - but that's expected - you are using self-signed certificate. Just return true there.
UPDATE:
I disagree with Tung's suggestion of adding self-signed certificate into the client's Trusted Root Certification Authorities. I think it can cause issues later on if you plan to distribute/support your software. For example, client might reinstall windows, or move his profile to another PC, or whatever - and understanding WHY your software suddenly stopped working will be a pain (again, i'm talking long-term - a year or two from now, when you completely forget this little "trick").
Instead i would rather suggest to "hardcode" your certificate (by comparing subject and thumbprint) into client's logic, something like this:
X509Certificate2 certificate = (X509Certificate2)cert;
if (certificate.Subject.StartsWith("CN=FAKE_SERVER_WHATEVER") &&
!string.IsNullOrEmpty(certificate.Thumbprint) &&
certificate.Thumbprint.ToLower() == "11c4446c572a9918ced3618728b91b3a07982787")
{
return true;
}
return false;

As the Microsoft link to download pvkimprt is broken and I am a fan of OpenSSL here I leave two solutions with OpenSSL.
VARIANT #1 - Self Signed Certificate
First you will need download OpenSSL and this configuration file. #Tung has said you can use perfectly self-signed certificate. Copy the downloaded configuration file in the same folder where you will run OpenSSL commands.
Lets generate the private key and certificate of Certification Authority:
openssl req -x509 -config openssl.cnf -newkey rsa:4096 -sha256 -out ssl-cacert.pem -keyout ssl-cakey.pem -outform PEM
*Use -nodes parameter to omit the passphrase, but for safety reasons personally I do not recommend it.
If you desire inspect the information of CA certificate, execute the follow command:
openssl x509 -purpose -in ssl-cacert.pem -inform PEM
Lets create the certificate request, Common Name must be set with the machine name:
openssl req -config openssl.cnf -newkey rsa:2048 -keyout ssl-serverkey.pem -sha256 -out ssl-server.csr -outform PEM
*Same note for -nodes parameter.
If you want inspect the certificate request information execute the command:
openssl req -text -noout -verify -in ssl-server.csr
Sign the certificate request with the generated CA certificate:
openssl x509 -req -days 365 -CA ssl-cacert.pem -CAkey ssl-cakey.pem -CAcreateserial -in ssl-server.csr -out ssl-server-certificate.pem
Lets make the self-signed certificate with PFX format:
openssl pkcs12 -export -out ssl-certificate.pfx -inkey ssl-serverkey.pem -in ssl-server-certificate.pem -certfile ssl-cacert.pem -name "SSL Self Signed Certificate"
Now you should import the .pfx certificate.
Double click on ssl-certificate.pfx file.
Select "Local Machine" option and Next.
Type the password and select the checkbox "Mark this key as exportable."
Select the radio button "Place all certificates in the following store".
Select Personal store and click in Next.
With this steps must work.
VARIANT #2 - Generate CA Certificate and Server Certificate
Personally I prefer this solution over the first because only I have to distribute the Root CA certificate to the clients.
First download this configuration file.
We will generate the Root CA certificate with the corresponding private key:
openssl req -x509 -config openssl.cnf -newkey rsa:4096 -sha256 -keyout ssl-cakey.pem -out ssl-cacert.pem -outform PEM
Lets check certificate properties:
openssl x509 -purpose -in ssl-cacert.pem -inform PEM
The information must show should look like this:
Certificate purposes:
SSL client : No
SSL client CA : Yes
SSL server : No
SSL server CA : Yes
Netscape SSL server : No
Netscape SSL server CA : Yes
S/MIME signing : No
S/MIME signing CA : Yes
S/MIME encryption : No
S/MIME encryption CA : Yes
CRL signing : Yes
CRL signing CA : Yes
Any Purpose : Yes
Any Purpose CA : Yes
OCSP helper : Yes
OCSP helper CA : Yes
Time Stamp signing : No
Time Stamp signing CA : Yes
-----BEGIN CERTIFICATE-----
MIIGLjCCBBagAwIBAgIJANCzs7UBFJMpMA0GCSqGSIb3DQEBCwUAMGgxCzAJBgNV
...
im1yDnB5nPwkPwZ9eRmlzIc6OaLZcfbFfSeSw8/ipKZcEJ1u+EFrB0JhuSbeLXtQ
N/8=
-----END CERTIFICATE-----
Create the certificate request with the following command:
openssl req -config openssl.cnf -newkey rsa:2048 -sha256 -keyout ssl-serverkey.pem -out ssl-servercert.csr -outform PEM
It's very important set the Common Name with the machine name of server.
Verify the information of this certificate request:
openssl req -text -noout -verify -in ssl-servercert.csr
The information shows must have the following format, check that the CN field in the section Subject is the name of server machine.
verify OK
Certificate Request:
Data:
Version: 0 (0x0)
Subject: C=US, ST=..., L=..., O=..., OU=..., CN=SERVERNAME
Subject Public Key Info:
Public Key Algorithm: rsaEncryption
Public-Key: (2048 bit)
Modulus:
00:aa:92:bd:87:75:18:6c:c0:23:3f:0b:5a:46:1a:
...
fe:13
Exponent: 65537 (0x10001)
Attributes:
Requested Extensions:
X509v3 Subject Key Identifier:
7E:7D:79:F4:CD:71:0E:90:3A:9A:F8:3F:83:7D:89:90:4D:D4:F0:12
X509v3 Basic Constraints:
CA:FALSE
X509v3 Key Usage:
Digital Signature, Key Encipherment, Data Encipherment
Signature Algorithm: sha256WithRSAEncryption
34:e1:b4:db:b2:87:cc:11:3e:85:3c:ed:ac:8d:d9:43:ae:b0:
...
56:84:29:f9
Create the certificates folder:
mkdir certificates
Create the database index file:
Windows: type NUL > index.txt
Unix: touch index.txt
Create the serial.txt file where is stored the current serial number:
echo '01' > serial.txt
Create the server certificate signing the certificate request for 2 years with the command. You will be prompted the pass phrase of CA certificate depending if you used -nodes parameter:
openssl ca -config openssl.cnf -days 730 -policy signing_policy -extensions v3_req -out ssl-servercert.pem -infiles ssl-servercert.csr
Then is displayed a text with the format:
Check that the request matches the signature
Signature ok
The Subject's Distinguished Name is as follows
countryName :PRINTABLE:'US'
stateOrProvinceName :ASN.1 12:'...'
localityName :ASN.1 12:'...'
organizationName :ASN.1 12:'...'
organizationalUnitName:ASN.1 12:'...'
commonName :ASN.1 12:'SERVERNAME'
Certificate is to be certified until Jul 4 23:26:59 2018 GMT (730 days)
Sign the certificate? [y/n]:
Select y and will prompted the follow text, select y one more time:
1 out of 1 certificate requests certified, commit? [y/n]
Export the generated certificate to PFX format:
openssl pkcs12 -export -out ssl-certificate.pfx -inkey ssl-serverkey.pem -in ssl-servercert.pem -name "SSL Signed Certificate"
You will need do the follow steps to enable SSL without problem:
On Server Machine:
Import the Root CA certificate (ssl-cacert.pem file) on Trusted Root Certification Authorities store selecting Computer account.
Import Server Certificate for SSL (ssl-certificate.pfx file) on Personal store selecting Computer account.
On Client Machines:
In each client machine you will need import the Root CA certificate (ssl-cacert.pem file) on Trusted Root Certification Authorities store selecting Computer account.
Feel free to make any changes or suggestions.