starting working on activity

src/BirdsiteLive.ActivityPub/ApDeserializer.cs

@@ -0,0 +1,30 @@
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub
+{
+    public class ApDeserializer
+    {
+        public static Activity ProcessActivity(string json)
+        {
+            var activity = JsonConvert.DeserializeObject<Activity>(json);
+            switch (activity.type)
+            {
+                case "Follow":
+                    return JsonConvert.DeserializeObject<ActivityFollow>(json);
+                case "Undo":
+                    var a = JsonConvert.DeserializeObject<ActivityUndo>(json);
+                    if(a.apObject.type == "Follow")
+                        return JsonConvert.DeserializeObject<ActivityUndoFollow>(json);
+                    break;
+            }
+
+            return null;
+        }
+
+        private class Ac : Activity
+        {
+            [JsonProperty("object")]
+            public Activity apObject { get; set; }
+        }
+    }
+}

src/BirdsiteLive.ActivityPub/BirdsiteLive.ActivityPub.csproj

@@ -5,6 +5,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Newtonsoft.Json" Version="12.0.2" />
     <PackageReference Include="System.Text.Json" Version="4.7.2" />
   </ItemGroup>
 

src/BirdsiteLive.ActivityPub/Models/Activity.cs

@@ -0,0 +1,16 @@
+using System.Text.Json.Serialization;
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub
+{
+    public class Activity
+    {
+        [JsonProperty("@context")]
+        public string context { get; set; }
+        public string id { get; set; }
+        public string type { get; set; }
+        public string actor { get; set; }
+        //[JsonProperty("object")]
+        //public string apObject { get; set; }
+    }
+}

src/BirdsiteLive.ActivityPub/Models/ActivityFollow.cs

@@ -0,0 +1,10 @@
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub
+{
+    public class ActivityFollow : Activity
+    {
+        [JsonProperty("object")]
+        public string apObject { get; set; }
+    }
+}

src/BirdsiteLive.ActivityPub/Models/ActivityUndo.cs

@@ -0,0 +1,10 @@
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub
+{
+    public class ActivityUndo : Activity
+    {
+        [JsonProperty("object")]
+        public Activity apObject { get; set; }
+    }
+}

src/BirdsiteLive.ActivityPub/Models/ActivityUndoFollow.cs

@@ -0,0 +1,10 @@
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub
+{
+    public class ActivityUndoFollow : Activity
+    {
+        [JsonProperty("object")]
+        public ActivityFollow apObject { get; set; }
+    }
+}

src/BirdsiteLive.ActivityPub/Models/Actor.cs

@@ -1,12 +1,14 @@
 using System;
 using System.Text.Json.Serialization;
+using Newtonsoft.Json;
 
 namespace BirdsiteLive.ActivityPub
 {
     public class Actor
     {
-        [JsonPropertyName("@context")]
+        //[JsonPropertyName("@context")]
-        public string[] context { get; set; } = new[] {"https://www.w3.org/ns/activitystreams", "https://w3id.org/security/v1"};
+        [JsonProperty("@context")]
+        public object[] context { get; set; } = new[] {"https://www.w3.org/ns/activitystreams", "https://w3id.org/security/v1" };
         public string id { get; set; }
         public string type { get; set; }
         public string preferredUsername { get; set; }

src/BirdsiteLive.Domain/ActivityPubService.cs

@@ -0,0 +1,26 @@
+using System.Net.Http;
+using System.Threading.Tasks;
+using BirdsiteLive.ActivityPub;
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.Domain
+{
+    public interface IActivityPubService
+    {
+        Task<Actor> GetUser(string objectId);
+    }
+
+    public class ActivityPubService : IActivityPubService
+    {
+        public async Task<Actor> GetUser(string objectId)
+        {
+            using (var httpClient = new HttpClient())
+            {
+                httpClient.DefaultRequestHeaders.Add("Accept", "application/json");
+                var result = await httpClient.GetAsync(objectId);
+                var content = await result.Content.ReadAsStringAsync();
+                return JsonConvert.DeserializeObject<Actor>(content);
+            }
+        }
+    }
+}

src/BirdsiteLive.Domain/UserService.cs

@@ -1,24 +1,33 @@
 using System;
+using System.Collections.Generic;
+using System.Security.Cryptography;
+using System.Text;
+using System.Threading.Tasks;
 using BirdsiteLive.ActivityPub;
 using BirdsiteLive.Common.Settings;
+using BirdsiteLive.Cryptography;
 using BirdsiteLive.Twitter.Models;
+using Tweetinvi.Core.Exceptions;
 
 namespace BirdsiteLive.Domain
 {
     public interface IUserService
     {
         Actor GetUser(TwitterUser twitterUser);
+        Task<bool> FollowRequestedAsync(string signature, string method, string path, string queryString, Dictionary<string, string> requestHeaders, ActivityFollow activity);
     }
 
     public class UserService : IUserService
     {
         private readonly ICryptoService _cryptoService;
+        private readonly IActivityPubService _activityPubService;
         private readonly string _host;
 
         #region Ctor
-        public UserService(InstanceSettings instanceSettings, ICryptoService cryptoService)
+        public UserService(InstanceSettings instanceSettings, ICryptoService cryptoService, IActivityPubService activityPubService)
         {
             _cryptoService = cryptoService;
+            _activityPubService = activityPubService;
             _host = $"https://{instanceSettings.Domain.Replace("https://",string.Empty).Replace("http://", string.Empty).TrimEnd('/')}";
         }
         #endregion
@@ -53,5 +62,78 @@ namespace BirdsiteLive.Domain
             };
             return user;
         }
+
+        public async Task<bool> FollowRequestedAsync(string signature, string method, string path, string queryString, Dictionary<string, string>  requestHeaders, ActivityFollow activity)
+        {
+            // Validate
+            if (!await ValidateSignature(activity.actor, signature, method, path, queryString, requestHeaders)) return false;
+
+            // Save Follow in DB
+
+            // Send Accept Activity 
+
+            
+            throw new NotImplementedException();
+        }
+
+        private async Task<bool> ValidateSignature(string actor, string rawSig, string method, string path, string queryString, Dictionary<string, string> requestHeaders)
+        {
+            var signatures = rawSig.Split(',');
+            var signature_header = new Dictionary<string, string>();
+            foreach (var signature in signatures)
+            {
+                var splitSig = signature.Replace("\"", string.Empty).Split('=');
+                signature_header.Add(splitSig[0], splitSig[1]);
+            }
+
+            signature_header["signature"] = signature_header["signature"] + "==";
+
+            var key_id = signature_header["keyId"];
+            var headers = signature_header["headers"];
+            var algorithm = signature_header["algorithm"];
+            var sig = Convert.FromBase64String(signature_header["signature"]);
+
+
+            var remoteUser = await _activityPubService.GetUser(actor);
+
+            var toDecode = remoteUser.publicKey.publicKeyPem.Trim().Remove(0, remoteUser.publicKey.publicKeyPem.IndexOf('\n'));
+            toDecode = toDecode.Remove(toDecode.LastIndexOf('\n')).Replace("\n", "");
+            var signKey = ASN1.ToRSA(Convert.FromBase64String(toDecode));
+
+            var toSign = new StringBuilder();
+            //var comparisonString = headers.Split(' ').Select(signed_header_name =>
+            //{
+            //    if (signed_header_name == "(request-target)")
+            //        return "(request-target): post /inbox";
+            //    else
+            //        return $"{signed_header_name}: {r.Headers[signed_header_name.ToUpperInvariant()]}";
+            //});
+
+            foreach (var headerKey in headers.Split(' '))
+            {
+                if (headerKey == "(request-target)") toSign.Append($"(request-target): {method.ToLower()} {path}{queryString}\n");
+                else toSign.Append($"{headerKey}: {string.Join(", ", requestHeaders[headerKey])}\n");
+            }
+            toSign.Remove(toSign.Length - 1, 1);
+
+            //var signKey = ASN1.ToRSA(Convert.FromBase64String(toDecode));
+
+            //new RSACryptoServiceProvider(keyId.publicKey.publicKeyPem);
+
+            //Create a new instance of RSACryptoServiceProvider.
+            RSACryptoServiceProvider key = new RSACryptoServiceProvider();
+
+            //Get an instance of RSAParameters from ExportParameters function.
+            RSAParameters RSAKeyInfo = key.ExportParameters(false);
+
+            //Set RSAKeyInfo to the public key values.
+            RSAKeyInfo.Modulus = Convert.FromBase64String(toDecode);
+
+            key.ImportParameters(RSAKeyInfo);
+
+            var result = signKey.VerifyData(Encoding.UTF8.GetBytes(toSign.ToString()), sig, HashAlgorithmName.SHA256, RSASignaturePadding.Pkcs1);
+
+            return result;
+        }
     }
 }

src/BirdsiteLive.sln

@@ -21,6 +21,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BirdsiteLive.Domain", "Bird
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BirdsiteLive.ActivityPub", "BirdsiteLive.ActivityPub\BirdsiteLive.ActivityPub.csproj", "{7463E1E2-9736-4A46-8507-010BDD8ECFBB}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "BirdsiteLive.ActivityPub.Tests", "Tests\BirdsiteLive.ActivityPub.Tests\BirdsiteLive.ActivityPub.Tests.csproj", "{1D713961-9926-41FF-8D6A-8A4B8D548484}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -55,6 +57,10 @@ Global
 		{7463E1E2-9736-4A46-8507-010BDD8ECFBB}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{7463E1E2-9736-4A46-8507-010BDD8ECFBB}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{7463E1E2-9736-4A46-8507-010BDD8ECFBB}.Release|Any CPU.Build.0 = Release|Any CPU
+		{1D713961-9926-41FF-8D6A-8A4B8D548484}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{1D713961-9926-41FF-8D6A-8A4B8D548484}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{1D713961-9926-41FF-8D6A-8A4B8D548484}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1D713961-9926-41FF-8D6A-8A4B8D548484}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -66,6 +72,7 @@ Global
 		{155D46A4-2D05-47F2-8FFC-0B7C412A7652} = {A32D3458-09D0-4E0A-BA4B-8C411B816B94}
 		{D48450EE-D8BD-4228-9864-043AC88F7EE0} = {4FEAD6BC-3C8E-451A-8CA1-FF1AF47D26CC}
 		{7463E1E2-9736-4A46-8507-010BDD8ECFBB} = {4FEAD6BC-3C8E-451A-8CA1-FF1AF47D26CC}
+		{1D713961-9926-41FF-8D6A-8A4B8D548484} = {A32D3458-09D0-4E0A-BA4B-8C411B816B94}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {69E8DCAD-4C37-4010-858F-5F94E6FBABCE}

src/BirdsiteLive/Controllers/UsersController.cs

@@ -4,9 +4,13 @@ using System.IO;
 using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
+using BirdsiteLive.ActivityPub;
 using BirdsiteLive.Domain;
 using BirdsiteLive.Twitter;
+using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Primitives;
+using Newtonsoft.Json;
 
 namespace BirdsiteLive.Controllers
 {
@@ -34,7 +38,8 @@ namespace BirdsiteLive.Controllers
             if (r.Contains("application/activity+json"))
             {
                 var apUser = _userService.GetUser(user);
-                return Json(apUser);
+                var jsonApUser = JsonConvert.SerializeObject(apUser);
+                return Content(jsonApUser, "application/json");
             }
 
             return View(user);
@@ -48,11 +53,27 @@ namespace BirdsiteLive.Controllers
             using (var reader = new StreamReader(Request.Body))
             {
                 var body = await reader.ReadToEndAsync();
-
+                var activity = ApDeserializer.ProcessActivity(body);
                 // Do something
+
+                switch (activity.type)
+                {
+                    case "Follow": 
+                        var succeeded = await _userService.FollowRequestedAsync(r.Headers["Signature"].First(), r.Method, r.Path, r.QueryString.ToString(), RequestHeaders(r.Headers), activity as ActivityFollow);
+                        if (succeeded) return Ok();
+                        else return Unauthorized();
+                        break;
+                    default:
+                        return Ok();
+                }
             }
 
             return Ok();
         }
+
+        private Dictionary<string, string> RequestHeaders(IHeaderDictionary header)
+        {
+            return header.ToDictionary<KeyValuePair<string, StringValues>, string, string>(h => h.Key, h => h.Value);
+        }
     }
 }

src/Tests/BirdsiteLive.ActivityPub.Tests/ActivityTests.cs

@@ -0,0 +1,33 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub.Tests
+{
+    //[TestClass]
+    //public class ActivityTests
+    //{
+    //    [TestMethod]
+    //    public void FollowDeserializationTest()
+    //    {
+    //        var json = "{ \"@context\":\"https://www.w3.org/ns/activitystreams\",\"id\":\"https://mastodon.technology/c94567cf-1fda-42ba-82fc-a0f82f63ccbe\",\"type\":\"Follow\",\"actor\":\"https://mastodon.technology/users/testtest\",\"object\":\"https://4a120ca2680e.ngrok.io/users/manu\"}";
+
+    //        var data = JsonConvert.DeserializeObject<Activity>(json);
+
+    //        Assert.AreEqual("https://mastodon.technology/c94567cf-1fda-42ba-82fc-a0f82f63ccbe", data.id);
+    //        Assert.AreEqual("Follow", data.type);
+    //        Assert.AreEqual("https://4a120ca2680e.ngrok.io/users/manu", data.apObject);
+    //    }
+
+    //    [TestMethod]
+    //    public void UndoDeserializationTest()
+    //    {
+    //        var json =
+    //            "{\"@context\":\"https://www.w3.org/ns/activitystreams\",\"id\":\"https://mastodon.technology/users/testtest#follows/225982/undo\",\"type\":\"Undo\",\"actor\":\"https://mastodon.technology/users/testtest\",\"object\":{\"id\":\"https://mastodon.technology/c94567cf-1fda-42ba-82fc-a0f82f63ccbe\",\"type\":\"Follow\",\"actor\":\"https://mastodon.technology/users/testtest\",\"object\":\"https://4a120ca2680e.ngrok.io/users/manu\"}}";
+
+    //        var data = JsonConvert.DeserializeObject<Activity>(json);
+    //        Assert.AreEqual("https://mastodon.technology/users/testtest#follows/225982/undo", data.id);
+    //        Assert.AreEqual("Undo", data.type);
+    //        Assert.AreEqual("https://4a120ca2680e.ngrok.io/users/manu", data.apObject);
+    //    }
+    //}
+}

src/Tests/BirdsiteLive.ActivityPub.Tests/ActorTests.cs

@@ -0,0 +1,21 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub.Tests
+{
+    [TestClass]
+    public class ActorTests
+    {
+        [TestMethod]
+        public void Deserialize()
+        {
+            var json =
+                "{\"@context\":[\"https://www.w3.org/ns/activitystreams\",\"https://w3id.org/security/v1\",{\"manuallyApprovesFollowers\":\"as:manuallyApprovesFollowers\",\"toot\":\"http://joinmastodon.org/ns#\",\"featured\":{\"@id\":\"toot:featured\",\"@type\":\"@id\"},\"alsoKnownAs\":{\"@id\":\"as:alsoKnownAs\",\"@type\":\"@id\"},\"movedTo\":{\"@id\":\"as:movedTo\",\"@type\":\"@id\"},\"schema\":\"http://schema.org#\",\"PropertyValue\":\"schema:PropertyValue\",\"value\":\"schema:value\",\"IdentityProof\":\"toot:IdentityProof\",\"discoverable\":\"toot:discoverable\"}],\"id\":\"https://mastodon.technology/users/testtest\",\"type\":\"Person\",\"following\":\"https://mastodon.technology/users/testtest/following\",\"followers\":\"https://mastodon.technology/users/testtest/followers\",\"inbox\":\"https://mastodon.technology/users/testtest/inbox\",\"outbox\":\"https://mastodon.technology/users/testtest/outbox\",\"featured\":\"https://mastodon.technology/users/testtest/collections/featured\",\"preferredUsername\":\"testtest\",\"name\":\"TESTEST\",\"summary\":\"\u003cp\u003etest \u003cbr /\u003edsqdq65d4sq56d456q4d8zd4q685d45qd4sqd2q1d5zq56d465qsd4q65sd21qsd23q1s5d64qsd8q465d4s5q1d6qsd35qs4dq6sd84q\u003c/p\u003e\",\"url\":\"https://mastodon.technology/@testtest\",\"manuallyApprovesFollowers\":false,\"discoverable\":false,\"publicKey\":{\"id\":\"https://mastodon.technology/users/testtest#main-key\",\"owner\":\"https://mastodon.technology/users/testtest\",\"publicKeyPem\":\"-----BEGIN PUBLIC KEY-----\nMIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAm7BlbWI/UD/YJj288h/5\nFB0gXZj0BjYVaK28uzTvb4w6eMu4qpbE9NI0bFqrloXzL3z6PaOCL4Myz9uJYolE\nZ9uNVi2OeZmHigNEOT3hkJWzddtrhkg8MLXKPdOETjhVWV3n+na7QWDDIXP7Fuvi\n+osA5LOoqtD1rYs87xUcWQPLCtVHs928FXsCdLO11ofXiNrancSzY17nkuufjWO+\ndLtvz1kx4Mt2V4Fu+DHskQAzPKU2tzGBrtlVQrk+1R63psIuZYDB6e4i7L6/d1Xl\nIQGmBeJfyxiuNIlbfZIbJ3xPYBQaVAnRKtyGVEFMWwZCqMySwc2LBX+rxI20zJ0R\n7wIDAQAB\n-----END PUBLIC KEY-----\n\"},\"tag\":[],\"attachment\":[],\"endpoints\":{\"sharedInbox\":\"https://mastodon.technology/inbox\"}}";
+
+
+            var actor = JsonConvert.DeserializeObject<Actor>(json);
+
+            
+        }
+    }
+}

src/Tests/BirdsiteLive.ActivityPub.Tests/ApDeserializerTests.cs

@@ -0,0 +1,35 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Newtonsoft.Json;
+
+namespace BirdsiteLive.ActivityPub.Tests
+{
+    [TestClass]
+    public class ApDeserializerTests
+    {
+        [TestMethod]
+        public void FollowDeserializationTest()
+        {
+            var json = "{ \"@context\":\"https://www.w3.org/ns/activitystreams\",\"id\":\"https://mastodon.technology/c94567cf-1fda-42ba-82fc-a0f82f63ccbe\",\"type\":\"Follow\",\"actor\":\"https://mastodon.technology/users/testtest\",\"object\":\"https://4a120ca2680e.ngrok.io/users/manu\"}";
+
+            var data = ApDeserializer.ProcessActivity(json) as ActivityFollow;
+
+            Assert.AreEqual("https://mastodon.technology/c94567cf-1fda-42ba-82fc-a0f82f63ccbe", data.id);
+            Assert.AreEqual("Follow", data.type);
+            Assert.AreEqual("https://4a120ca2680e.ngrok.io/users/manu", data.apObject);
+        }
+
+        [TestMethod]
+        public void UndoDeserializationTest()
+        {
+            var json =
+                "{\"@context\":\"https://www.w3.org/ns/activitystreams\",\"id\":\"https://mastodon.technology/users/testtest#follows/225982/undo\",\"type\":\"Undo\",\"actor\":\"https://mastodon.technology/users/testtest\",\"object\":{\"id\":\"https://mastodon.technology/c94567cf-1fda-42ba-82fc-a0f82f63ccbe\",\"type\":\"Follow\",\"actor\":\"https://mastodon.technology/users/testtest\",\"object\":\"https://4a120ca2680e.ngrok.io/users/manu\"}}";
+
+            var data = ApDeserializer.ProcessActivity(json) as ActivityUndoFollow;
+            Assert.AreEqual("https://mastodon.technology/users/testtest#follows/225982/undo", data.id);
+            Assert.AreEqual("Undo", data.type);
+            Assert.AreEqual("Follow", data.apObject.type);
+            Assert.AreEqual("https://mastodon.technology/users/testtest", data.apObject.actor);
+            Assert.AreEqual("https://4a120ca2680e.ngrok.io/users/manu", data.apObject.apObject);
+        }
+    }
+}

src/Tests/BirdsiteLive.ActivityPub.Tests/BirdsiteLive.ActivityPub.Tests.csproj

@@ -0,0 +1,20 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.5.0" />
+    <PackageReference Include="MSTest.TestAdapter" Version="2.1.0" />
+    <PackageReference Include="MSTest.TestFramework" Version="2.1.0" />
+    <PackageReference Include="coverlet.collector" Version="1.2.0" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\BirdsiteLive.ActivityPub\BirdsiteLive.ActivityPub.csproj" />
+  </ItemGroup>
+
+</Project>