static void AssertScramSha256(SaslMechanismScramSha256 sasl, string prefix)
{
const string expected = "c=biws,r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0,p=dHzbZapWIk4jUhN+Ute9ytag9zjfMHgsqmmiz7AndVQ=";
const string challenge1 = "r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0,s=W22ZaJ0SNY7soEsUEjb6gQ==,i=4096";
const string challenge2 = "v=6rriTRBi23WpRR/wtup+mMhUZUn/dB5nLTJRsjl95G4=";
const string entropy = "rOprNGfwEbeRWgbNEkqO";
string token;
sasl.cnonce = entropy;
Assert.IsTrue(sasl.SupportsInitialResponse, "{0}: SupportsInitialResponse", prefix);
var challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(null)));
Assert.AreEqual("n,,n=user,r=" + entropy, challenge, "{0}: initial SCRAM-SHA-256 challenge response does not match the expected string.", prefix);
Assert.IsFalse(sasl.IsAuthenticated, "{0}: should not be authenticated yet.", prefix);
token = Convert.ToBase64String(Encoding.UTF8.GetBytes(challenge1));
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(token)));
Assert.AreEqual(expected, challenge, "{0}: second SCRAM-SHA-256 challenge response does not match the expected string.", prefix);
Assert.IsFalse(sasl.IsAuthenticated, "{0}: should not be authenticated yet.", prefix);
token = Convert.ToBase64String(Encoding.UTF8.GetBytes(challenge2));
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(token)));
Assert.AreEqual(string.Empty, challenge, "{0}: third SCRAM-SHA-256 challenge should be an empty string.", prefix);
Assert.IsTrue(sasl.IsAuthenticated, "{0}: SCRAM-SHA-256 should be authenticated now.", prefix);
Assert.Throws <InvalidOperationException> (() => sasl.Challenge(string.Empty));
}
public void TestScramSha256()
{
const string cnonce = "rOprNGfwEbeRWgbNEkqO";
var uri = new Uri("imap://elwood.innosoft.com");
var credentials = new NetworkCredential("user", "pencil");
var sasl = new SaslMechanismScramSha256(credentials, cnonce);
string token;
var challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(null)));
Assert.AreEqual("n,,n=user,r=" + cnonce, challenge, "Initial SCRAM-SHA-256 challenge response does not match the expected string.");
Assert.IsFalse(sasl.IsAuthenticated, "SCRAM-SHA-256 should not be authenticated yet.");
token = Convert.ToBase64String(Encoding.UTF8.GetBytes("r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0,s=W22ZaJ0SNY7soEsUEjb6gQ==,i=4096"));
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(token)));
const string expected = "c=biws,r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0,p=dHzbZapWIk4jUhN+Ute9ytag9zjfMHgsqmmiz7AndVQ=";
Assert.AreEqual(expected, challenge, "Second SCRAM-SHA-256 challenge response does not match the expected string.");
Assert.IsFalse(sasl.IsAuthenticated, "SCRAM-SHA-256 should not be authenticated yet.");
token = Convert.ToBase64String(Encoding.UTF8.GetBytes("v=6rriTRBi23WpRR/wtup+mMhUZUn/dB5nLTJRsjl95G4="));
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(token)));
Assert.AreEqual(string.Empty, challenge, "Third SCRAM-SHA-256 challenge should be an empty string.");
Assert.IsTrue(sasl.IsAuthenticated, "SCRAM-SHA-256 should be authenticated now.");
}
public void TestScramSha256()
{
var credentials = new NetworkCredential("user", "pencil");
var sasl = new SaslMechanismScramSha256(credentials);
var uri = new Uri("imap://elwood.innosoft.com");
AssertScramSha256(sasl, "NetworkCredential");
sasl = new SaslMechanismScramSha256("user", "pencil");
AssertScramSha256(sasl, "user/pass");
}
public void TestArgumentExceptions()
{
var credentials = new NetworkCredential("username", "password");
var uri = new Uri("smtp://localhost");
SaslMechanism sasl;
Assert.Throws <ArgumentNullException> (() => new SaslException(null, SaslErrorCode.MissingChallenge, "message"));
sasl = new SaslMechanismCramMd5(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(uri, null));
Assert.Throws <NotSupportedException> (() => sasl.Challenge(null));
sasl = new SaslMechanismDigestMd5(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(uri, null));
Assert.Throws <NotSupportedException> (() => sasl.Challenge(null));
sasl = new SaslMechanismLogin(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, null));
Assert.Throws <NotSupportedException> (() => sasl.Challenge(null));
sasl = new SaslMechanismNtlm(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(uri, null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismOAuth2(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(uri, null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismPlain(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismScramSha1(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(uri, null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismScramSha256(uri, credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
}
static void AssertSaslException(SaslMechanismScramSha256 sasl, string challenge, SaslErrorCode code)
{
var token = Encoding.ASCII.GetBytes(challenge);
try {
sasl.Challenge(Convert.ToBase64String(token));
} catch (SaslException sex) {
Assert.AreEqual(code, sex.ErrorCode, "ErrorCode");
return;
} catch (Exception ex) {
Assert.Fail("SaslException expected, but got: {0}", ex.GetType().Name);
return;
}
Assert.Fail("SaslException expected.");
}
public void TestArgumentExceptions()
{
var credentials = new NetworkCredential("username", "password");
var uri = new Uri("smtp://localhost");
var sasl = new SaslMechanismScramSha256(credentials);
Assert.DoesNotThrow(() => sasl.Challenge(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, (string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256((string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256("username", null));
}
public void TestArgumentExceptions()
{
var credentials = new NetworkCredential("username", "password");
var sasl = new SaslMechanismScramSha256(credentials);
Assert.DoesNotThrow(() => sasl.Challenge(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256("username", null));
sasl = new SaslMechanismScramSha256Plus(credentials);
Assert.DoesNotThrow(() => sasl.Challenge(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256Plus(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256Plus(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256Plus("username", null));
}
public void TestSaslExceptions()
{
const string nonce = "r=rOprNGfwEbeRWgbNEkqO%hvYDpWUa2RaTCAfuxFIlj)hNlF$k0";
const string salt = "s=W22ZaJ0SNY7soEsUEjb6gQ==";
const string iterations = "i=4096";
const string expected = "c=biws," + nonce + ",p=dHzbZapWIk4jUhN+Ute9ytag9zjfMHgsqmmiz7AndVQ=";
const string challenge1 = nonce + "," + salt + "," + iterations;
const string challenge2 = "v=6rriTRBi23WpRR/wtup+mMhUZUn/dB5nLTJRsjl95G4=";
const string entropy = "rOprNGfwEbeRWgbNEkqO";
var sasl = new SaslMechanismScramSha256("user", "pencil")
{
cnonce = entropy
};
string challenge, token;
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(null)));
Assert.AreEqual("n,,n=user,r=" + entropy, challenge, "initial SCRAM-SHA-256 challenge response does not match the expected string.");
Assert.IsFalse(sasl.IsAuthenticated, "should not be authenticated yet.");
AssertSaslException(sasl, challenge1.Replace(salt + ",", string.Empty), SaslErrorCode.IncompleteChallenge); // missing salt
AssertSaslException(sasl, challenge1.Replace(nonce + ",", string.Empty), SaslErrorCode.IncompleteChallenge); // missing nonce
AssertSaslException(sasl, challenge1.Replace("," + iterations, string.Empty), SaslErrorCode.IncompleteChallenge); // missing iterations
AssertSaslException(sasl, challenge1.Replace(nonce, "r=asfhajksfhkafhakhafk"), SaslErrorCode.InvalidChallenge); // invalid nonce
AssertSaslException(sasl, challenge1.Replace(iterations, "i=abcd"), SaslErrorCode.InvalidChallenge); // invalid iterations
token = Convert.ToBase64String(Encoding.UTF8.GetBytes(challenge1));
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(token)));
Assert.AreEqual(expected, challenge, "second SCRAM-SHA-256 challenge response does not match the expected string.");
Assert.IsFalse(sasl.IsAuthenticated, "should not be authenticated yet.");
AssertSaslException(sasl, "x=abcdefg", SaslErrorCode.InvalidChallenge);
AssertSaslException(sasl, "v=6rriTRBi23WpRR/wtup+mMhUZUn/dB5nLTJRsjl9", SaslErrorCode.IncorrectHash); // incorrect hash length
AssertSaslException(sasl, "v=AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=", SaslErrorCode.IncorrectHash); // incorrect hash
token = Convert.ToBase64String(Encoding.UTF8.GetBytes(challenge2));
challenge = Encoding.UTF8.GetString(Convert.FromBase64String(sasl.Challenge(token)));
Assert.AreEqual(string.Empty, challenge, "third SCRAM-SHA-256 challenge should be an empty string.");
Assert.IsTrue(sasl.IsAuthenticated, "SCRAM-SHA-256 should be authenticated now.");
Assert.Throws <InvalidOperationException> (() => sasl.Challenge(string.Empty));
}
public void TestArgumentExceptions()
{
var credentials = new NetworkCredential("username", "password");
var uri = new Uri("smtp://localhost");
SaslMechanism sasl;
Assert.Throws <ArgumentNullException> (() => new SaslException(null, SaslErrorCode.MissingChallenge, "message"));
sasl = new SaslMechanismCramMd5(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(uri, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismCramMd5("username", null));
Assert.Throws <NotSupportedException> (() => sasl.Challenge(null));
sasl = new SaslMechanismDigestMd5(credentials)
{
Uri = uri
};
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(uri, (string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismDigestMd5("username", null));
Assert.Throws <NotSupportedException> (() => sasl.Challenge(null));
sasl = new SaslMechanismLogin(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin((Uri)null, Encoding.UTF8, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, Encoding.UTF8, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin((Uri)null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin((Uri)null, Encoding.UTF8, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, Encoding.UTF8, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, Encoding.UTF8, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin((Uri)null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(Encoding.UTF8, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin((Encoding)null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(Encoding.UTF8, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(Encoding.UTF8, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismLogin("username", null));
Assert.Throws <NotSupportedException> (() => sasl.Challenge(null));
sasl = new SaslMechanismNtlm(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm((Uri)null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm((Uri)null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(uri, (string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismNtlm("username", null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismOAuth2(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2((Uri)null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2((Uri)null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(uri, (string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismOAuth2("username", null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismPlain(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain((Uri)null, Encoding.UTF8, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, Encoding.UTF8, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain((Uri)null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain((Uri)null, Encoding.UTF8, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, Encoding.UTF8, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, Encoding.UTF8, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain((Uri)null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(Encoding.UTF8, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain((Encoding)null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(Encoding.UTF8, null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(Encoding.UTF8, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain(null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismPlain("username", null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismScramSha1(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(uri, (string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1((string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha1("username", null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
sasl = new SaslMechanismScramSha256(credentials);
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null, credentials));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null, "username", "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, (string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(uri, "username", null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256(null));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256((string)null, "password"));
Assert.Throws <ArgumentNullException> (() => new SaslMechanismScramSha256("username", null));
Assert.DoesNotThrow(() => sasl.Challenge(null));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create(null, uri, Encoding.UTF8, credentials));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create("PLAIN", null, Encoding.UTF8, credentials));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create("PLAIN", uri, null, credentials));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create("PLAIN", uri, Encoding.UTF8, null));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create(null, uri, credentials));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create("PLAIN", null, credentials));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.Create("PLAIN", uri, null));
Assert.Throws <ArgumentNullException> (() => SaslMechanism.SaslPrep(null));
}
