static bool IsSigner(OneKey key)
{
if (key[usageKey].AsString().Contains("EDHOC"))
{
if (key[CoseKeyKeys.KeyType].Equals(GeneralValues.KeyType_EC) &&
key.ContainsName(CoseKeyParameterKeys.EC_D))
{
return(true);
}
if (key[CoseKeyKeys.KeyType].Equals(GeneralValues.KeyType_OKP) &&
key.ContainsName(CoseKeyParameterKeys.OKP_D))
{
return(true);
}
}
return(false);
}
/// <summary>
/// Create an EDHOC context for a suplicant to generate messages from.
/// </summary>
/// <param name="contextKey">Either shared secret or signing to key to used to do identity proofing for</param>
public EdhocInitiator(OneKey contextKey)
{
switch ((GeneralValuesInt)contextKey[CoseKeyKeys.KeyType].AsInt32())
{
case GeneralValuesInt.KeyType_Octet:
_fSymmetricSecret = true;
_SharedSecret = contextKey;
break;
case GeneralValuesInt.KeyType_EC2:
case GeneralValuesInt.KeyType_OKP:
_fSymmetricSecret = false;
if (!contextKey.ContainsName(CoseKeyParameterKeys.EC_D))
{
throw new Exception("Need to supply a private key with the signing key");
}
_SigningKey = contextKey;
break;
case GeneralValuesInt.KeyType_RSA:
default:
throw new Exception("Unknown key type for secret");
}
// Save the items in the "Our" side of the arrays.
_kid[0] = contextKey[CoseKeyKeys.KeyIdentifier];
#if true
_SessionId[0] = new byte[2];
_random.NextBytes(_SessionId[0]);
_Nonce[0] = new byte[8];
_random.NextBytes(_Nonce[0]);
#else
_SessionId[0] = Encoding.UTF8.GetBytes("kid client");
_Nonce[0] = Encoding.UTF8.GetBytes("Nonce Client");
#endif
_Keys[0] = OneKey.GenerateKey(null, GeneralValues.KeyType_OKP, "X25519");
}
public void Process(Request request, Response response)
{
// Is this processable?
if (response.StatusCode != StatusCode.Unauthorized ||
response.ContentFormat != 65008)
{
return;
}
try {
// Init from the response data
Oauth.AsInfo info = new Oauth.AsInfo(response.Payload);
// Missage this as needed.
string aSServer = info.ASServer;
// Need to build one from scratch
if (!authServers.ContainsKey(info.ASServer))
{
Console.WriteLine($"No security association is setup for {info.ASServer}");
return;
}
AuthServerInfo asi = authServers[info.ASServer];
if (asi.ClientLink == null)
{
asi.ClientLink = new CoapClient(new Uri(info.ASServer));
if (asi.UseDTLS)
{
asi.ClientLink.EndPoint = new DTLSClientEndPoint(asi.TlsKey);
asi.ClientLink.EndPoint.Start();
}
}
// M00BUG - need to make sure that this will pickup a port number if given.
string audience = $"{request.URI.Scheme}://{request.URI.Authority}";
Oauth.Request myRequest = new Oauth.Request("client_credentials")
{
Audience = audience,
Scope = CBORObject.FromObject(request.UriPath)
};
myRequest.Profile = Profile;
byte[] payload = myRequest.EncodeToBytes();
asi.ClientLink.Timeout = 2 * 60 * 1000;
Response asResponse = asi.ClientLink.Post(payload, MediaType.ApplicationCbor);
if (asResponse == null)
{
asi.ClientLink.EndPoint.Stop();
asi.ClientLink = null;
Console.WriteLine($"Timed out requesting token from {info.ASServer}");
return;
}
if (asResponse.StatusCode != StatusCode.Created)
{
// We had an error condition appear
if (asResponse.Payload != null)
{
CBORObject obj = CBORObject.DecodeFromBytes(asResponse.Payload);
int error = obj["error"].AsInt32();
string errorText = "";
if (obj.ContainsKey("error_description"))
{
errorText = obj["error_description"].AsString();
}
Console.WriteLine(
$"Recieved an error {asResponse.StatusCode} with error no = {error} and description '{errorText}'");
}
else
{
Console.WriteLine($"Received and error {asResponse.StatusCode} from the AS but no text");
}
return;
}
Oauth.Response myResponse = new Oauth.Response(asResponse.Payload);
// default profile for client -
#if false
if (Profile != null && myResponse.Profile != Profile)
{
Console.WriteLine("AS Server returned an unexpected profile {0}", myResponse.Profile);
return;
}
#endif
myResponse.Profile = Oauth.ProfileIds.Coap_Dtls;
// Post token to resource server
CoapClient client = new CoapClient();
client.Uri = new Uri($"coap://{request.URI.Authority}/authz-info");
client.Timeout = 10000; // 1 second
Response tknResponse = client.Post(myResponse.Token, MediaType.ApplicationCbor);
if (tknResponse == null)
{
Console.WriteLine("Post of token failed w/ no response");
return;
}
if (tknResponse.StatusCode != StatusCode.Created)
{
Console.WriteLine($"Post of token failed with error {tknResponse.StatusCode}");
return;
}
Confirmation cnf = myResponse.Confirmation;
Request newRequest = new Request(request.Method);
newRequest.Payload = request.Payload;
newRequest.SetOptions(request.GetOptions());
DTLSClientEndPoint endPoint = null;
switch (myResponse.Profile)
{
case Oauth.ProfileIds.Coap_Dtls: {
OneKey key = cnf.Key;
endPoint = new DTLSClientEndPoint(cnf.Key);
endPoint.Start();
newRequest.EndPoint = endPoint;
newRequest.URI = new Uri($"coaps://{request.URI.Authority}/{request.URI.AbsolutePath}");
}
break;
case Oauth.ProfileIds.Coap_Oscore: {
OneKey oneKey = cnf.Key;
byte[] salt = null;
if (oneKey.ContainsName("slt"))
{
salt = oneKey[CBORObject.FromObject("slt")].GetByteString();
}
CBORObject alg = null;
if (oneKey.ContainsName(CoseKeyKeys.Algorithm))
{
alg = oneKey[CoseKeyKeys.Algorithm];
}
CBORObject kdf = null;
if (oneKey.ContainsName(CBORObject.FromObject("kdf")))
{
kdf = oneKey[CBORObject.FromObject("kdf")];
}
SecurityContext oscoapContext = SecurityContext.DeriveContext(
oneKey[CoseKeyParameterKeys.Octet_k].GetByteString(),
oneKey[CBORObject.FromObject("sid")].GetByteString(),
oneKey[CBORObject.FromObject("rid")].GetByteString(),
salt, alg, kdf);
newRequest.OscoapContext = oscoapContext;
}
break;
default:
Console.WriteLine("Cannot rewrite as we don't recognize the profile");
return;
}
newRequest.Respond += delegate(Object sender, ResponseEventArgs e)
{
Response responseN = e.Response;
if (responseN == null)
{
Console.WriteLine("Request timeout");
}
else
{
Console.WriteLine(Utils.ToString(responseN));
Console.WriteLine("Time (ms): " + responseN.RTT);
}
if (endPoint != null)
{
endPoint.Stop();
}
};
newRequest.Send();
}
catch (Exception e) {
Console.WriteLine("Error processing AceAuthz - " + e.ToString());
}
}
static KeySet LoadKeys(string fileName)
{
if (fileName == null)
{
fileName = "ServerKeys.cbor";
}
KeySet keys = new KeySet();
FileStream fs = new FileStream(fileName, FileMode.Open);
using (BinaryReader reader = new BinaryReader(fs)) {
byte[] data = reader.ReadBytes((int)fs.Length);
CBORObject obj = CBORObject.DecodeFromBytes(data);
for (int i = 0; i < obj.Count; i++)
{
OneKey key = new OneKey(obj[i]);
string[] usages = key[_UsageKey].AsString().Split(' ');
foreach (String usage in usages)
{
if (usage == "oscoap")
{
SecurityContext ctx = SecurityContext.DeriveContext(
key[CoseKeyParameterKeys.Octet_k].GetByteString(),
key[CBORObject.FromObject("RecipID")].GetByteString(),
key[CBORObject.FromObject("SenderID")].GetByteString(), null,
key[CoseKeyKeys.Algorithm]);
SecurityContextSet.AllContexts.Add(ctx);
break;
}
#if DEV_VERSION
else if (usage == "oscoap-group")
{
SecurityContext ctx = SecurityContext.DeriveGroupContext(
key[CoseKeyParameterKeys.Octet_k].GetByteString(),
key[CoseKeyKeys.KeyIdentifier].GetByteString(),
key[CBORObject.FromObject("sender")][CBORObject.FromObject("ID")].GetByteString(), null,
null, key[CoseKeyKeys.Algorithm]);
ctx.Sender.SigningKey = new OneKey(obj[i]["sign"]);
foreach (CBORObject recipient in key[CBORObject.FromObject("recipients")].Values)
{
ctx.AddRecipient(recipient[CBORObject.FromObject("ID")].GetByteString(),
new OneKey(recipient["sign"]));
}
SecurityContextSet.AllContexts.Add(ctx);
}
#endif
else if (usage == "dtls")
{
if (key.HasPrivateKey())
{
DtlsSignKeys.AddKey(key);
}
else
{
DtlsValidateKeys.AddKey(key);
}
}
else if (usage == "edhoc")
{
if (key[CoseKeyKeys.KeyType].Equals(GeneralValues.KeyType_EC) ||
key[CoseKeyKeys.KeyType].Equals(GeneralValues.KeyType_OKP))
{
if (key.ContainsName(CoseKeyParameterKeys.EC_D))
{
edhocSign = key;
}
else
{
edhocKeys.AddKey(key);
}
}
else
{
edhocKeys.AddKey(key);
}
}
}
if ((usages.Length != 1) || (usages[0] != "oscoap"))
{
keys.AddKey(key);
}
}
reader.Close();
}
return(keys);
}