Aspnetcore: Blazor WASM .NET 5 RC2 and Azure Cosmos DB - System.Security.Cryptography.Algorithms is not supported on this platform

Created on 30 Sep 2020 · 13Comments · Source: dotnet/aspnetcore

Bug

I have a vanilla Blazor WASM (standalone) application reading a container from Azure Cosmos DB. Before upgrading to .NET 5 RC1 it was working fine. This is the same application I had issues with in #26043. After upgrading packages to RC2 I still get exceptions (see image below) in the Developer Console.

Program.cs

``` C#
public class Program
{
public static async Task Main(string[] args)
{
var builder = WebAssemblyHostBuilder.CreateDefault(args);
builder.RootComponents.Add("app");

    builder.Services.AddScoped(sp => new HttpClient { BaseAddress = new Uri(builder.HostEnvironment.BaseAddress) });
    builder.Services.AddHttpClient();
    builder.Services.AddSingleton<CosmosClient>(serviceProvider =>
    {
        IHttpClientFactory httpClientFactory = serviceProvider.GetRequiredService<IHttpClientFactory>();

        CosmosClientOptions cosmosClientOptions = new CosmosClientOptions
        {
            HttpClientFactory = httpClientFactory.CreateClient,
            ConnectionMode = ConnectionMode.Gateway
        };

        return new CosmosClient("<endpoint-connectionString>", cosmosClientOptions);
    });

    await builder.Build().RunAsync();
}

}


### Packages

<PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="5.0.0-rtm.20479.13" />
<PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="5.0.0-rtm.20479.13" PrivateAssets="all" />
<PackageReference Include="Microsoft.Azure.Cosmos" Version="3.13.0" />
<PackageReference Include="Microsoft.Extensions.Http" Version="6.0.0-alpha.1.20420.3" />
<PackageReference Include="System.Net.Http.Json" Version="6.0.0-alpha.1.20420.3" />

```

Exceptions

External area-blazor blazor-wasm bug

Source

ylr-research

All 13 comments

Some types were brought back in rc2 (https://github.com/dotnet/runtime/issues/40076) but I don't think HMACSHA256 was one of them.

https://github.com/dotnet/runtime/blob/b1ca1f4eb040e42045718e265775f79eea982d32/src/libraries/System.Security.Cryptography.Algorithms/src/System/Security/Cryptography/HMACSHA256.cs#L17-L18

Reference https://github.com/Azure/azure-cosmos-dotnet-v3/issues/1865

campersau on 30 Sep 2020

@ylr-research thanks for contacting us.

As described by @campersau this is a known limitation in 5.0.

javiercn on 30 Sep 2020

We believe things are better in RC2, @lewing can you confirm?

HaoK on 30 Sep 2020

SHA256 hashes are in net5.0 but not HMACSHA256 so this will still fail.

lewing on 30 Sep 2020

@HaoK I have installed the RC2 (see image) and the must current packages, and this still fails.

    <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly" Version="5.0.0-rtm.20502.9" />
    <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.DevServer" Version="5.0.0-rtm.20502.9" PrivateAssets="all" />
    <PackageReference Include="Microsoft.Azure.Cosmos" Version="3.13.0" />
    <PackageReference Include="Microsoft.Extensions.Http" Version="6.0.0-alpha.1.20420.3" />
    <PackageReference Include="Microsoft.Extensions.Localization" Version="5.0.0-rtm.20502.9" />
    <PackageReference Include="System.Net.Http.Json" Version="6.0.0-alpha.1.20420.3" />

@lewing, in my code I don't specify which encryption method should be use. Thus, I'd say is defaulted in the AzureCosmos SDK.

ylr-research on 2 Oct 2020

as a matter of fact, here it is where AzureCosmos SDK is defaulting the encryption method.

C# public GatewayAccountReader(Uri serviceEndpoint, IComputeHash stringHMACSHA256Helper, bool hasResourceToken, string resourceToken, ConnectionPolicy connectionPolicy, CosmosHttpClient httpClient) { this.httpClient = httpClient; this.serviceEndpoint = serviceEndpoint; this.authKeyHashFunction = stringHMACSHA256Helper; this.hasAuthKeyResourceToken = hasResourceToken; this.authKeyResourceToken = resourceToken; this.connectionPolicy = connectionPolicy; }
@ealsur do I have a way to set the encryption method?

ylr-research on 3 Oct 2020

The code uses byte[] hashPayLoad = stringHMACSHA256Helper.ComputeHash(payload.Buffer); which seems to have this implementation: https://github.com/Azure/azure-cosmos-dotnet-v3/blob/master/Microsoft.Azure.Cosmos/src/Authorization/SecureStringHMACSHA256Helper.cs#L20

Currently I don't see anything in the public contract of the SDK to inject your implementation, I'm guessing that the hash is part of the contract of the service, right @j82w?

ealsur on 3 Oct 2020

@ealsur I suspect the correct link is https://github.com/Azure/azure-cosmos-dotnet-v3/blob/master/Microsoft.Azure.Cosmos/src/Authorization/StringHMACSHA256Hash.cs

lewing on 3 Oct 2020

👍1

@lewing SecureString isn't recommended for new development.

j82w on 3 Oct 2020

right, I was just trying to point out the correct file. I've edited the comment for clarity.

lewing on 3 Oct 2020

Folks are claiming above that this wasn't resolved in RC2. @lewing can you please share a summary of what's the current state of this? Is there pending work here?