Develop Reference

C# Coinbase Pro API How to Trouble Shoot Responses. 401

I keep Getting 401 responses from coinbase pro and I have double checked my passphrase and api key and they are correct. Is there any other reason I would get Unauth response
var timestamp = DateTimeOffset.UtcNow.ToUnixTimeSeconds().ToString("F0", CultureInfo.InvariantCulture);
var method = "GET";
var requestPath = "/accounts";
var body = "";
var data = timestamp + method + requestPath + body;
var secret = "***";
var signedMessage = GetHMACInHex(secret, data);
var client = new HttpClient()
{
BaseAddress = new Uri("https://api.pro.coinbase.com")
};
client.DefaultRequestHeaders.Add("CB-ACCESS-SIGN", signedMessage);
client.DefaultRequestHeaders.Add("CB-ACCESS-KEY", "***");
client.DefaultRequestHeaders.Add("CB-ACCESS-TIMESTAMP", timestamp);
client.DefaultRequestHeaders.Add("CB-ACCESS-PASSPHRASE", "***");
client.DefaultRequestHeaders.Add("User-Agent", "CoinbaseProClient");
This is how I Sign the Data
static string GetHMACInHex(string key, string data)
{
var decoded = Convert.FromBase64String(key);
var dataBytes = Encoding.UTF8.GetBytes(data);
using (var hmac = new HMACSHA256(decoded))
{
var hash = hmac.ComputeHash(dataBytes);
return Convert.ToBase64String(hash);
}
}

401 status code is returned by Coinbase when following validation of the resource fails on POST or PUT requests:
authentication_error- Invalid auth (generic)
invalid_token- Invalid Oauth token
revoked_token- Revoked Oauth
token
expired_token- Expired Oauth token
If your problem is not listed here, you may miss to pass DefaultRequestHeaders.
client.DefaultRequestHeaders
.Accept
.Add(new MediaTypeWithQualityHeaderValue("application/json"));

Using Key by Azure Key Vault to Encrypt and Decrypt text

I'm trying use a key from Azure Key Vault to Encrypt and Decrypt the cookies of a web API.
To encryption proccess I'm using the RSA, in that class:
public class SimpleRSA
{
private RSA _rsa;
public SimpleRSA(RSA rsa)
{
_rsa = rsa;
}
public string EncryptAsync(string value)
{
var byteData = Encoding.Unicode.GetBytes(value);
var encryptedText = _rsa.Encrypt(byteData, RSAEncryptionPadding.OaepSHA1);
var encodedText = Convert.ToBase64String(encryptedText);
return encodedText;
}
public string DecryptAsync(string encryptedText)
{
var encryptedBytes = Convert.FromBase64String(encryptedText);
var decryptionResult = _rsa.Decrypt(encryptedBytes, RSAEncryptionPadding.OaepSHA1);
var decryptedText = Encoding.Unicode.GetString(decryptionResult);
return decryptedText;
}
}
And I'm getting my RSA from the Key, using that code:
public RSA GetRSA(string appId, string appSecret)
{
AuthenticationCallback callback = async (authority, resource, scope) =>
{
var authContext = new AuthenticationContext(authority);
var credential = new ClientCredential(appId, appSecret);
var authResult = await authContext.AcquireTokenAsync(resource, credential);
return authResult.AccessToken;
};
var client = new KeyVaultClient(callback);
var result = client.GetKeyAsync(_vaultBaseUrl, _keyId).Result;
var key = result.Key;
return key.ToRSA();
}
I got the RSA from my Azure Key Vault and I managed encrypt my string. The problem is when I'm trying Decrypt the value. In that process I got that error:
System.Security.Cryptography.CryptographicException: 'Error decoding OAEP padding.'
I think that can be happening because I'm without the private keys in RSA, but I've tried use this method to get the RSA with private key::
key.ToRSA(true);
But a got that error:
So, I don't know how I can complete this process. Are there other way to do that? Or what's wrong?

If you want to use Azure Key Vault to Encrypt and Decrypt text, you can use SDK Azure.Security.KeyVault.Keys to implement it.
For example
Install SDK
Install-Package Azure.Security.KeyVault.Keys -Version 4.0.3
Install-Package Azure.Identity -Version 1.1.1
Code
ClientSecretCredential clientSecretCredential = new ClientSecretCredential(tenantId, // your tenant id
clientId, // your AD application appId
clientSecret // your AD application app secret
);
//get key
var KeyVaultName = "<your kay vault name>";
KeyClient keyClient = new KeyClient(new Uri($"https://{KeyVaultName}.vault.azure.net/"), clientSecretCredential);;
var keyName="<your key name>"
var key = await keyClient.GetKeyAsync(keyName);
// create CryptographyClient
CryptographyClient cryptoClient = new CryptographyClient(key.Value.Id, clientSecretCredential);
var str ="test"
Console.WriteLine("The String used to be encrypted is : " +str );
Console.WriteLine("-------------encrypt---------------");
var byteData = Encoding.Unicode.GetBytes(str);
var encryptResult = await cryptoClient.EncryptAsync(EncryptionAlgorithm.RsaOaep, byteData);
var encodedText = Convert.ToBase64String(encryptResult.Ciphertext);
Console.WriteLine(encodedText);
Console.WriteLine("-------------dencrypt---------------");
var encryptedBytes = Convert.FromBase64String(encodedText);
var dencryptResult = await cryptoClient.DecryptAsync(EncryptionAlgorithm.RsaOaep, encryptedBytes);
var decryptedText = Encoding.Unicode.GetString(dencryptResult.Plaintext);
Console.WriteLine(decryptedText);

Key Vault can store three item types: Keys, Secrets and Certificates. Keys are always asymmetric - RSA or Elliptic Curve, and the private keys don't leave KV. What you need is to use a symmetric key, but you need to store that as a Secret, not a key.
So store a 256-bit random secret in KV, call it MyCoolCryptoKey, pull that symmetric key into your C# code and use that as a key for AES.

How to generate JWT Bearer Flow OAuth access tokens from a .net core client?

I'm having trouble getting my .NET Core client to generate OAuth access tokens for a salesforce endpoint that requires OAuth of type 'JWT Bearer Flow'.
It seems there are limited .NET Framework examples that show a .NET client doing this, however none that show a .NET Core client doing it
e.g.
https://salesforce.stackexchange.com/questions/53662/oauth-jwt-token-bearer-flow-returns-invalid-client-credentials
So in my .NET Core 3.1 app i've generated a self signed certificate, added the private key to the above example's code when loading in the certificate, however a System.InvalidCastExceptionexception exception occurs on this line:
var rsa = certificate.GetRSAPrivateKey() as RSACryptoServiceProvider;
Exception:
System.InvalidCastException: 'Unable to cast object of type 'System.Security.Cryptography.RSACng' to type 'System.Security.Cryptography.RSACryptoServiceProvider'.'
It appears that this private key is used in the JWT Bearer Flow as part of the signature, and perhaps RSACryptoServiceProvider is not used in .NET core as it was in .NET Framework.
My question is this - is there actually a way in .NET Core to generate access tokens for the OAuth JWT Bearer Flow?
Full code that I'm using:
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
var token = GetAccessToken();
}
static dynamic GetAccessToken()
{
// get the certificate
var certificate = new X509Certificate2(#"C:\temp\cert.pfx");
// create a header
var header = new { alg = "RS256" };
// create a claimset
var expiryDate = GetExpiryDate();
var claimset = new
{
iss = "xxxxxx",
prn = "xxxxxx",
aud = "https://test.salesforce.com",
exp = expiryDate
};
// encoded header
var headerSerialized = JsonConvert.SerializeObject(header);
var headerBytes = Encoding.UTF8.GetBytes(headerSerialized);
var headerEncoded = ToBase64UrlString(headerBytes);
// encoded claimset
var claimsetSerialized = JsonConvert.SerializeObject(claimset);
var claimsetBytes = Encoding.UTF8.GetBytes(claimsetSerialized);
var claimsetEncoded = ToBase64UrlString(claimsetBytes);
// input
var input = headerEncoded + "." + claimsetEncoded;
var inputBytes = Encoding.UTF8.GetBytes(input);
// signature
var rsa = (RSACryptoServiceProvider) certificate.GetRSAPrivateKey();
var cspParam = new CspParameters
{
KeyContainerName = rsa.CspKeyContainerInfo.KeyContainerName,
KeyNumber = rsa.CspKeyContainerInfo.KeyNumber == KeyNumber.Exchange ? 1 : 2
};
var aescsp = new RSACryptoServiceProvider(cspParam) { PersistKeyInCsp = false };
var signatureBytes = aescsp.SignData(inputBytes, "SHA256");
var signatureEncoded = ToBase64UrlString(signatureBytes);
// jwt
var jwt = headerEncoded + "." + claimsetEncoded + "." + signatureEncoded;
var client = new WebClient();
client.Encoding = Encoding.UTF8;
var uri = "https://login.salesforce.com/services/oauth2/token";
var content = new NameValueCollection();
content["assertion"] = jwt;
content["grant_type"] = "urn:ietf:params:oauth:grant-type:jwt-bearer";
string response = Encoding.UTF8.GetString(client.UploadValues(uri, "POST", content));
var result = JsonConvert.DeserializeObject<dynamic>(response);
return result;
}
static int GetExpiryDate()
{
var utc0 = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
var currentUtcTime = DateTime.UtcNow;
var exp = (int)currentUtcTime.AddMinutes(4).Subtract(utc0).TotalSeconds;
return exp;
}
static string ToBase64UrlString(byte[] input)
{
return Convert.ToBase64String(input).TrimEnd('=').Replace('+', '-').Replace('/', '_');
}

Well - it turns out posting to stackoverflow gets the brain cogs turning.
The answer ended up being doing a deep dive to find a similar issue here and using the solution from x509certificate2 sign for jwt in .net core 2.1
I ended up replacing the following code:
var cspParam = new CspParameters
{
KeyContainerName = rsa.CspKeyContainerInfo.KeyContainerName,
KeyNumber = rsa.CspKeyContainerInfo.KeyNumber == KeyNumber.Exchange ? 1 : 2
};
var aescsp = new RSACryptoServiceProvider(cspParam) { PersistKeyInCsp = false };
var signatureBytes = aescsp.SignData(inputBytes, "SHA256");
var signatureEncoded = ToBase64UrlString(signatureBytes);
With this code which makes use of the System.IdentityModel.Tokens.Jwt nuget package:
var signingCredentials = new X509SigningCredentials(certificate, "RS256");
var signature = JwtTokenUtilities.CreateEncodedSignature(input, signingCredentials);
Full code after solution:
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
var token = GetAccessToken();
}
static dynamic GetAccessToken()
{
// get the certificate
var certificate = new X509Certificate2(#"C:\temp\cert.pfx");
// create a header
var header = new { alg = "RS256" };
// create a claimset
var expiryDate = GetExpiryDate();
var claimset = new
{
iss = "xxxxx",
prn = "xxxxx",
aud = "https://test.salesforce.com",
exp = expiryDate
};
// encoded header
var headerSerialized = JsonConvert.SerializeObject(header);
var headerBytes = Encoding.UTF8.GetBytes(headerSerialized);
var headerEncoded = ToBase64UrlString(headerBytes);
// encoded claimset
var claimsetSerialized = JsonConvert.SerializeObject(claimset);
var claimsetBytes = Encoding.UTF8.GetBytes(claimsetSerialized);
var claimsetEncoded = ToBase64UrlString(claimsetBytes);
// input
var input = headerEncoded + "." + claimsetEncoded;
var inputBytes = Encoding.UTF8.GetBytes(input);
var signingCredentials = new X509SigningCredentials(certificate, "RS256");
var signature = JwtTokenUtilities.CreateEncodedSignature(input, signingCredentials);
// jwt
var jwt = headerEncoded + "." + claimsetEncoded + "." + signature;
var client = new WebClient();
client.Encoding = Encoding.UTF8;
var uri = "https://test.salesforce.com/services/oauth2/token";
var content = new NameValueCollection();
content["assertion"] = jwt;
content["grant_type"] = "urn:ietf:params:oauth:grant-type:jwt-bearer";
string response = Encoding.UTF8.GetString(client.UploadValues(uri, "POST", content));
var result = JsonConvert.DeserializeObject<dynamic>(response);
return result;
}
static int GetExpiryDate()
{
var utc0 = new DateTime(1970, 1, 1, 0, 0, 0, 0, DateTimeKind.Utc);
var currentUtcTime = DateTime.UtcNow;
var exp = (int)currentUtcTime.AddMinutes(4).Subtract(utc0).TotalSeconds;
return exp;
}
static string ToBase64UrlString(byte[] input)
{
return Convert.ToBase64String(input).TrimEnd('=').Replace('+', '-').Replace('/', '_');
}

I am replying to this question just because such a similar answer would have helped me a lot when I landed on this page the first time.
First of all you don't have to generate the JWT from the C# client.
To generate a JWT token you can use this website: https://jwt.io/
There is a very well done video showing how to generate a JWT token:
https://www.youtube.com/watch?v=cViU2-xVscA&t=1680s
Once generated, use it from your C# client to call the get access_token endpoint
https://developer.salesforce.com/docs/atlas.en-us.api_iot.meta/api_iot/qs_auth_access_token.htm
(Watch the video on YT)
If all is correct you will get the access_token
To run the API calls, all you need is the access_token and not the JWT.
Once you have it add it to the HTTP calls like this
public static void AddBearerToken(this HttpRequestMessage request, string accessToken)
{
request.Headers.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", accessToken);
}
From time to time the access_token will expire. To check its validity you can call the token introspect api
https://help.salesforce.com/s/articleView?id=sf.remoteaccess_oidc_token_introspection_endpoint.htm&type=5
You need to pass two additional parameters: client_id and client_secret
The client_id is the Consumer Key. You get it from the Connected App in Salesforce
The client_server is the Consumer Secret. You get it from Connected App in Salesforce
If the introspect token API returns a response with
{ active: false, ... }
it means that the access_token is expired and you need to issue a new one.
To issue a new access_token simply call the "/services/oauth2/token" again using the same JWT.

Adding an SSL Certificate programmatically to get working https

I have some code that is supposed to add an ssl certifacate to a port. It does say it has succesfully added a certificate, but when i host the website and then type in the localhost url (localhost:{port}) the page keeps loading. I don't understand why it doesn't work.
I already tried to host the website without ssl and that worked fine so that's not the problem.
public static class Certificate
{
public static void Standard(int port)
{
var certSubjectName = "HelloMyNameIsHank";
var expiresIn = TimeSpan.FromHours(1);
var cert = GenerateCert(certSubjectName, expiresIn);
Console.WriteLine("Generated certificate, {0}Thumbprint: {1}{0}", Environment.NewLine, cert.Thumbprint);
RegisterSslOnPort(port, cert.Thumbprint);
Console.WriteLine($"Registerd SSL on port: {port}");
}
private static void RegisterSslOnPort(int port, string certThumbprint)
{
var appId = Guid.NewGuid();
string arguments = $"http add sslcert ipport=0.0.0.0:{port} certhash={certThumbprint} appid={{{appId}}}";
ProcessStartInfo procStartInfo = new ProcessStartInfo("netsh", arguments);
procStartInfo.RedirectStandardOutput = true;
procStartInfo.UseShellExecute = false;
procStartInfo.CreateNoWindow = true;
var process = Process.Start(procStartInfo);
while (!process.StandardOutput.EndOfStream)
{
string line = process.StandardOutput.ReadLine();
Console.WriteLine(line);
}
process.WaitForExit();
}
public static X509Certificate2 GenerateCert(string certName, TimeSpan expiresIn)
{
var store = new X509Store(StoreName.Root, StoreLocation.LocalMachine);
store.Open(OpenFlags.ReadWrite);
var existingCert = store.Certificates.Find(X509FindType.FindBySubjectName, certName, false);
if (existingCert.Count > 0)
{
store.Close();
return existingCert[0];
}
else
{
var cert = CreateSelfSignedCertificate(certName, expiresIn);
store.Add(cert);
store.Close();
return cert;
}
}
public static X509Certificate2 CreateSelfSignedCertificate(string subjectName, TimeSpan expiresIn)
{
// create DN for subject and issuer
var dn = new CX500DistinguishedName();
dn.Encode("CN=" + subjectName, X500NameFlags.XCN_CERT_NAME_STR_NONE);
// create a new private key for the certificate
CX509PrivateKey privateKey = new CX509PrivateKey();
privateKey.ProviderName = "Microsoft Base Cryptographic Provider v1.0";
privateKey.MachineContext = true;
privateKey.Length = 2048;
privateKey.KeySpec = X509KeySpec.XCN_AT_SIGNATURE; // use is not limited
privateKey.ExportPolicy = X509PrivateKeyExportFlags.XCN_NCRYPT_ALLOW_PLAINTEXT_EXPORT_FLAG;
privateKey.Create();
// Use the stronger SHA512 hashing algorithm
var hashobj = new CObjectId();
hashobj.InitializeFromAlgorithmName(ObjectIdGroupId.XCN_CRYPT_HASH_ALG_OID_GROUP_ID,
ObjectIdPublicKeyFlags.XCN_CRYPT_OID_INFO_PUBKEY_ANY,
AlgorithmFlags.AlgorithmFlagsNone, "SHA512");
// add extended key usage if you want - look at MSDN for a list of possible OIDs
var oid = new CObjectId();
oid.InitializeFromValue("1.3.6.1.5.5.7.3.1"); // SSL server
var oidlist = new CObjectIds();
oidlist.Add(oid);
var eku = new CX509ExtensionEnhancedKeyUsage();
eku.InitializeEncode(oidlist);
// Create the self signing request
var cert = new CX509CertificateRequestCertificate();
cert.InitializeFromPrivateKey(X509CertificateEnrollmentContext.ContextMachine, privateKey, "");
cert.Subject = dn;
cert.Issuer = dn; // the issuer and the subject are the same
cert.NotBefore = DateTime.Now;
// this cert expires immediately. Change to whatever makes sense for you
cert.NotAfter = DateTime.Now.Add(expiresIn);
cert.X509Extensions.Add((CX509Extension)eku); // add the EKU
cert.HashAlgorithm = hashobj; // Specify the hashing algorithm
cert.Encode(); // encode the certificate
// Do the final enrollment process
var enroll = new CX509Enrollment();
enroll.InitializeFromRequest(cert); // load the certificate
enroll.CertificateFriendlyName = subjectName; // Optional: add a friendly name
string csr = enroll.CreateRequest(); // Output the request in base64
// and install it back as the response
enroll.InstallResponse(InstallResponseRestrictionFlags.AllowUntrustedCertificate,
csr, EncodingType.XCN_CRYPT_STRING_BASE64, ""); // no password
// output a base64 encoded PKCS#12 so we can import it back to the .Net security classes
var base64encoded = enroll.CreatePFX("", // no password, this is for internal consumption
PFXExportOptions.PFXExportChainWithRoot);
// instantiate the target class with the PKCS#12 data (and the empty password)
return new System.Security.Cryptography.X509Certificates.X509Certificate2(
System.Convert.FromBase64String(base64encoded), "",
// mark the private key as exportable (this is usually what you want to do)
System.Security.Cryptography.X509Certificates.X509KeyStorageFlags.Exportable
);
}
}
I want to be able to host my website with https. If anyone knows why this doesn't work please tell me.
I'm using httplistener for hosting. I don't want to use ASP.NET and/or IIS.
I'm not to familiar with ssl certificates so I would also really appreciate some code snippets even if it's just pseudo-code.

Nodejs verify jwt token from .net failed

I create token from .net by this C# code (with System.IdentityModel.Tokens.Jwt):
var keybytes = Convert.FromBase64String("MYCUSTOMCODELONGMOD4NEEDBEZE");
var signingCredentials = new SigningCredentials(
new InMemorySymmetricSecurityKey(keybytes),
SecurityAlgorithms.HmacSha256Signature,
SecurityAlgorithms.Sha256Digest);
var nbf = DateTime.UtcNow.AddDays(-100);
var exp = DateTime.UtcNow.AddDays(100);
var payload = new JwtPayload(null, "", new List<Claim>(), nbf, exp);
var user = new Dictionary<string, object>();
user.Add("userId", "1");
payload.Add("user", user);
payload.Add("success", true);
var jwtToken = new JwtSecurityToken(new JwtHeader(signingCredentials), payload);
var jwtTokenHandler = new JwtSecurityTokenHandler();
var resultToken = jwtTokenHandler.WriteToken(jwtToken);
I send the resultToken to nodejs and verify it (with jsonwebtoken library) with below code:
var jwt = require('jsonwebtoken');
var result = jwt.verify(
resultToken,
new Buffer('MYCUSTOMCODELONGMOD4NEEDBEZE').toString('base64'),
{ algorithms: ['HS256'] },
function(err, decoded) {
if (err) {
console.log('decode token failed with error: '+ JSON.stringify(err));
}
}
);
I got the error: invalid signature. The resultToken content:
eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE0OTQ4MTMxMTUsIm5iZiI6MTQ3NzUzMzExNSwidXNlciI6eyJ1c2VySWQiOiIxIn0sInN1Y2Nlc3MiOnRydWV9.4bjYyIUFMouz-ctFyxXkJ_QcJJQofCEFffUuazWFjGw
I have debug it on jwt.io with above signature (MYCUSTOMCODELONGMOD4NEEDBEZE) and secret base64 encoded checked, it's ok.
I have tried a signature without base64 encoded by chaging keybytes in C# code:
var keybytes = Encoding.UTF8.GetBytes("MYCUSTOMCODELONGMOD4NEEDBEZE");
And it verified successfully in nodejs. So i think the issue comes from my nodejs code when verify a base64 encoded signature. Did i miss some options when verify token or somethings?

I have no idea what you did but this snippet is working for me with the token you provided above.
var jwt = require('jwt-simple')
var secret = new Buffer('MYCUSTOMCODELONGMOD4NEEDBEZE').toString('base64')
var token = 'eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE0OTQ4MTMxMTUsIm5iZiI6MTQ3NzUzMzExNSwidXNlciI6eyJ1c2VySWQiOiIxIn0sInN1Y2Nlc3MiOnRydWV9.4bjYyIUFMouz-ctFyxXkJ_QcJJQofCEFffUuazWFjGw'
var decoded = jwt.decode(token, secret)
console.log(decoded)
Output:
❯ node jwt.js
{ exp: 1494813115,
nbf: 1477533115,
user: { userId: '1' },
success: true }
Using jsonwebtoken library
// var jwt = require('jwt-simple')
var jwt = require('jsonwebtoken');
var secret = Buffer.from('MYCUSTOMCODELONGMOD4NEEDBEZE', 'base64')
var token = 'eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJleHAiOjE0OTQ4MTMxMTUsIm5iZiI6MTQ3NzUzMzExNSwidXNlciI6eyJ1c2VySWQiOiIxIn0sInN1Y2Nlc3MiOnRydWV9.4bjYyIUFMouz-ctFyxXkJ_QcJJQofCEFffUuazWFjGw'
jwt.verify(token, secret, { algorithms: ['HS256'] }, function(err, decoded) {
if (err) {
console.log(err)
} else {
console.log(decoded)
}
})
Again still working fine.
The only difference i can see is the secret.