public HttpResponseMessage ReferendumLookup(HttpRequestMessage requestMessage, int id)
{
// Lookup the referendum and 404 it if we cannot find it, otherwise return it as-is
using (ReferendumRepository repo = new ReferendumRepository())
{
Referendum referendum = repo.Get(id);
if (referendum == null)
{
return(requestMessage.CreateResponse(HttpStatusCode.NotFound));
}
return(requestMessage.CreateResponse(HttpStatusCode.OK, referendum));
}
}
public HttpResponseMessage ReferendumSummary(HttpRequestMessage requestMessage)
{
using (ReferendumRepository repo = new ReferendumRepository())
{
Referendum[] referendums = repo.GetAll();
if (referendums != null)
{
foreach (Referendum referendum in referendums)
{
referendum.StripVoters();
}
}
return(requestMessage.CreateResponse(HttpStatusCode.OK, referendums));
}
}
public HttpResponseMessage ReferendumVote(HttpRequestMessage requestMessage, int id, VoteRequest request)
{
// Find the referendum that matches
using (ReferendumRepository repo = new ReferendumRepository())
{
Referendum referendum = repo.Get(id);
if (referendum == null)
{
return(requestMessage.CreateResponse(HttpStatusCode.NotFound));
}
// First perform the same checks that the client performs - required fields are provided, the Ethereum address is valid and in our voting list
List <string> invalidFields = new List <string>();
List <string> errorMessages = new List <string>();
if (string.IsNullOrEmpty(request?.Address))
{
invalidFields.Add("voteAddress");
errorMessages.Add("Your Ethereum address is required");
}
else if (request.Address.Length != 42)
{
invalidFields.Add("voteAddress");
errorMessages.Add("Your Ethereum address is not valid");
}
else
{
bool found = false;
foreach (Voter voter in referendum.Electorate)
{
if (voter.Address.ToLower() != request.Address.ToLower())
{
continue;
}
if (voter.VoteCount == 0)
{
continue;
}
found = true;
break;
}
if (!found)
{
invalidFields.Add("voteAddress");
errorMessages.Add("Your Ethereum address is not entitled to vote");
}
}
if (request.Vote < 1)
{
invalidFields.Add("voteAnswer");
errorMessages.Add("Your need to select your voting intention");
}
else if (request.Vote > referendum.Answers.Length)
{
invalidFields.Add("voteAnswer");
errorMessages.Add("Your vote is not valid for this referendum");
}
if (string.IsNullOrEmpty(request.SignedVoteMessage))
{
invalidFields.Add("signature");
errorMessages.Add("Your need to sign your vote");
}
else if (request.SignedVoteMessage.Length != 132)
{
invalidFields.Add("signature");
errorMessages.Add("Your signature's hex string is not the correct length");
}
// Now confirm that the signature is that which we expect, if not generate an error
if (!invalidFields.Contains("signature"))
{
try
{
MessageSigner signer = new MessageSigner();
string message = "R" + id + " V" + request.Vote + " " + request.Address.ToLower();
string v1Address = signer.EcRecover(new Nethereum.Util.Sha3Keccack().CalculateHash(Encoding.UTF8.GetBytes(message)), request.SignedVoteMessage);
string v2Address = signer.EcRecover(new Nethereum.Util.Sha3Keccack().CalculateHash(Encoding.UTF8.GetBytes("\u0019Ethereum Signed Message:\n" + message.Length + message)), request.SignedVoteMessage);
string trezorAddress = signer.EcRecover(new Nethereum.Util.Sha3Keccack().CalculateHash(Encoding.UTF8.GetBytes("\u0019Ethereum Signed Message:\n" + char.ConvertFromUtf32(message.Length) + message)), request.SignedVoteMessage);
if (v1Address.ToLower() != request.Address.ToLower() && v2Address.ToLower() != request.Address.ToLower() && trezorAddress.ToLower() != request.Address.ToLower())
{
invalidFields.Add("signature");
errorMessages.Add("Your signature is not correct");
}
}
catch (Exception ex)
{
invalidFields.Add("signature");
errorMessages.Add("Unexpected error decoding your signature: " + ex.Message);
}
}
// Check timings for the vote
if (DateTime.UtcNow < referendum.StartTime)
{
invalidFields.Add(string.Empty);
errorMessages.Add("The vote has not yet started");
}
if (DateTime.UtcNow > referendum.EndTime)
{
invalidFields.Add(string.Empty);
errorMessages.Add("The vote has already ended");
}
// If any errors are present, return them now.
if (errorMessages.Count > 0)
{
return(requestMessage.CreateResponse(HttpStatusCode.BadRequest, new ValidationResponse(invalidFields.ToArray(), errorMessages.ToArray())));
}
// Add or update the vote in the backend repo
repo.Vote(id, request.Address, request.Vote, request.SignedVoteMessage);
// Confirm this to the user
return(requestMessage.CreateResponse(HttpStatusCode.NoContent));
}
}