Protocol part of the federation authentication on FE2

fe2-android/app/src/main/java/com/github/dedis/popstellar/di/DataRegistryModule.kt

@@ -18,6 +18,7 @@ import com.github.dedis.popstellar.model.network.method.message.data.election.El
 import com.github.dedis.popstellar.model.network.method.message.data.election.ElectionOpen
 import com.github.dedis.popstellar.model.network.method.message.data.election.ElectionResult
 import com.github.dedis.popstellar.model.network.method.message.data.election.ElectionSetup
+import com.github.dedis.popstellar.model.network.method.message.data.federation.Challenge
 import com.github.dedis.popstellar.model.network.method.message.data.lao.CreateLao
 import com.github.dedis.popstellar.model.network.method.message.data.lao.GreetLao
 import com.github.dedis.popstellar.model.network.method.message.data.lao.StateLao
@@ -39,6 +40,7 @@ import com.github.dedis.popstellar.utility.handler.data.ConsensusHandler
 import com.github.dedis.popstellar.utility.handler.data.ElectionHandler
 import com.github.dedis.popstellar.utility.handler.data.HandlerContext
 import com.github.dedis.popstellar.utility.handler.data.LaoHandler
+import com.github.dedis.popstellar.utility.handler.data.LinkedOrganizationsHandler
 import com.github.dedis.popstellar.utility.handler.data.MeetingHandler
 import com.github.dedis.popstellar.utility.handler.data.ReactionHandler
 import com.github.dedis.popstellar.utility.handler.data.RollCallHandler
@@ -67,7 +69,8 @@ object DataRegistryModule {
       chirpHandler: ChirpHandler,
       reactionHandler: ReactionHandler,
       transactionCoinHandler: TransactionCoinHandler,
-      witnessMessageHandler: WitnessingHandler
+      witnessMessageHandler: WitnessingHandler,
+      linkedOrganizationsHandler: LinkedOrganizationsHandler
   ): DataRegistry {
 
     val builder = DataRegistry.Builder()
@@ -249,6 +252,13 @@ object DataRegistryModule {
       transactionCoinHandler.handlePostTransactionCoin(context, postTransactionCoin)
     }
 
+    // Federation
+    builder.add(Objects.FEDERATION, Action.CHALLENGE, Challenge::class.java) {
+        context: HandlerContext,
+        challenge: Challenge ->
+      linkedOrganizationsHandler.handleChallenge(context, challenge)
+    }
+
     return builder.build()
   }
 
@@ -315,6 +325,9 @@ object DataRegistryModule {
     // Digital Cash
     builder.add(Objects.COIN, Action.POST_TRANSACTION, PostTransactionCoin::class.java, null)
 
+    // Federation
+    builder.add(Objects.FEDERATION, Action.CHALLENGE, Challenge::class.java, null)
+
     return builder.build()
   }
 }

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/method/message/data/Action.kt

@@ -40,6 +40,10 @@ enum class Action
   KEY("key"),
   POST_TRANSACTION("post_transaction"),
   AUTH("authenticate"),
+  CHALLENGE_REQUEST("challenge_request"),
+  CHALLENGE("challenge"),
+  INIT("init"),
+  EXPECT("expect"),
   RUMOR("rumor");
 
   /**

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/method/message/data/Objects.kt

@@ -23,6 +23,7 @@ enum class Objects
   REACTION("reaction"),
   COIN("coin"),
   POPCHA("popcha"),
+  FEDERATION("federation"),
   GOSSIP("gossip");
 
   /**
@@ -41,7 +42,7 @@ enum class Objects
       COIN.`object`,
       MESSAGE.`object` -> true
 
-      // Consensus and Popcha are for now the ones excluded from persistence
+      // Consensus, Popcha and Federation are for now the ones excluded from persistence
       else -> false
     }
   }

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/method/message/data/federation/Challenge.kt

@@ -0,0 +1,48 @@
+package com.github.dedis.popstellar.model.network.method.message.data.federation
+
+import com.github.dedis.popstellar.model.network.method.message.data.Action
+import com.github.dedis.popstellar.model.network.method.message.data.Data
+import com.github.dedis.popstellar.model.network.method.message.data.Objects
+import com.google.gson.annotations.SerializedName
+import kotlin.math.max
+
+/** Challenge sent by the server */
+class Challenge
+/**
+ * Constructor for a data Challenge
+ *
+ * @param value value of the Challenge (A 32 bytes array encoded in hexadecimal)
+ * @param validUntil expiration time of the Challenge
+ */
+(val value: String, validUntil: Long) : Data {
+  @SerializedName("valid_until") val validUntil: Long
+
+  init {
+    this.validUntil = max(0L, validUntil)
+  }
+
+  override val `object`: String
+    get() = Objects.FEDERATION.`object`
+
+  override val action: String
+    get() = Action.CHALLENGE.action
+
+  override fun equals(other: Any?): Boolean {
+    if (this === other) {
+      return true
+    }
+    if (other == null || javaClass != other.javaClass) {
+      return false
+    }
+    val that = other as Challenge
+    return value == that.value && validUntil == that.validUntil
+  }
+
+  override fun hashCode(): Int {
+    return java.util.Objects.hash(value, validUntil)
+  }
+
+  override fun toString(): String {
+    return "Challenge{value='$value', valid_until='$validUntil'}"
+  }
+}

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/method/message/data/federation/ChallengeRequest.kt

@@ -0,0 +1,42 @@
+package com.github.dedis.popstellar.model.network.method.message.data.federation
+
+import com.github.dedis.popstellar.model.Immutable
+import com.github.dedis.popstellar.model.network.method.message.data.Action
+import com.github.dedis.popstellar.model.network.method.message.data.Data
+import com.github.dedis.popstellar.model.network.method.message.data.Objects
+
+/** Data sent to get a challenge */
+@Immutable
+class ChallengeRequest
+/**
+ * Constructor for a data Challenge Request
+ *
+ * @param timestamp time of the Challenge Request
+ */
+(val timestamp: Long) : Data {
+
+  override val `object`: String
+    get() = Objects.FEDERATION.`object`
+
+  override val action: String
+    get() = Action.CHALLENGE_REQUEST.action
+
+  override fun equals(other: Any?): Boolean {
+    if (this === other) {
+      return true
+    }
+    if (other == null || javaClass != other.javaClass) {
+      return false
+    }
+    val that = other as ChallengeRequest
+    return timestamp == that.timestamp
+  }
+
+  override fun hashCode(): Int {
+    return java.util.Objects.hash(timestamp)
+  }
+
+  override fun toString(): String {
+    return "ChallengeRequest{timestamp='$timestamp'}"
+  }
+}

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/method/message/data/federation/FederationExpect.kt

@@ -0,0 +1,54 @@
+package com.github.dedis.popstellar.model.network.method.message.data.federation
+
+import com.github.dedis.popstellar.model.network.method.message.MessageGeneral
+import com.github.dedis.popstellar.model.network.method.message.data.Action
+import com.github.dedis.popstellar.model.network.method.message.data.Data
+import com.github.dedis.popstellar.model.network.method.message.data.Objects
+import com.google.gson.annotations.SerializedName
+
+/** Federation Expect message */
+class FederationExpect
+/**
+ * Constructor for a data Federation Expect
+ *
+ * @param laoId ID of the remote LAO
+ * @param serverAddress public address of the remote organizer server
+ * @param publicKey public key of the remote organizer
+ * @param challenge challenge for the server
+ */
+(
+    @SerializedName("lao_id") val laoId: String,
+    @SerializedName("server_address") val serverAddress: String,
+    @SerializedName("public_key") val publicKey: String,
+    val challenge: MessageGeneral
+) : Data {
+
+  override val `object`: String
+    get() = Objects.FEDERATION.`object`
+
+  override val action: String
+    get() = Action.EXPECT.action
+
+  override fun equals(other: Any?): Boolean {
+    if (this === other) {
+      return true
+    }
+    if (other == null || javaClass != other.javaClass) {
+      return false
+    }
+    val that = other as FederationExpect
+    return laoId == that.laoId &&
+        serverAddress == that.serverAddress &&
+        publicKey == that.publicKey &&
+        challenge == that.challenge
+  }
+
+  override fun hashCode(): Int {
+    return java.util.Objects.hash(laoId, serverAddress, publicKey, challenge)
+  }
+
+  override fun toString(): String {
+    return "FederationExpect{lao_id='$laoId', server_address='$serverAddress'," +
+        "public_key='$publicKey', challenge='$challenge'}"
+  }
+}

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/method/message/data/federation/FederationInit.kt

@@ -0,0 +1,54 @@
+package com.github.dedis.popstellar.model.network.method.message.data.federation
+
+import com.github.dedis.popstellar.model.network.method.message.MessageGeneral
+import com.github.dedis.popstellar.model.network.method.message.data.Action
+import com.github.dedis.popstellar.model.network.method.message.data.Data
+import com.github.dedis.popstellar.model.network.method.message.data.Objects
+import com.google.gson.annotations.SerializedName
+
+/** Initiates a federation link */
+class FederationInit
+/**
+ * Constructor for a data Federation Init
+ *
+ * @param laoId ID of the remote LAO
+ * @param serverAddress public address of the remote organizer server
+ * @param publicKey public key of the remote organizer
+ * @param challenge challenge from the other server
+ */
+(
+    @SerializedName("lao_id") val laoId: String,
+    @SerializedName("server_address") val serverAddress: String,
+    @SerializedName("public_key") val publicKey: String,
+    val challenge: MessageGeneral
+) : Data {
+
+  override val `object`: String
+    get() = Objects.FEDERATION.`object`
+
+  override val action: String
+    get() = Action.INIT.action
+
+  override fun equals(other: Any?): Boolean {
+    if (this === other) {
+      return true
+    }
+    if (other == null || javaClass != other.javaClass) {
+      return false
+    }
+    val that = other as FederationInit
+    return laoId == that.laoId &&
+        serverAddress == that.serverAddress &&
+        publicKey == that.publicKey &&
+        challenge == that.challenge
+  }
+
+  override fun hashCode(): Int {
+    return java.util.Objects.hash(laoId, serverAddress, publicKey, challenge)
+  }
+
+  override fun toString(): String {
+    return "FederationInit{lao_id='$laoId', server_address='$serverAddress'," +
+        "public_key='$publicKey', challenge='$challenge'}"
+  }
+}

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/network/serializer/JsonUtils.kt

@@ -30,6 +30,7 @@ object JsonUtils {
   const val CONNECT_TO_LAO_SCHEMA = "protocol/qrcode/connect_to_lao.json"
   const val POP_TOKEN_SCHEME = "protocol/qrcode/pop_token.json"
   const val MAIN_PK_SCHEME = "protocol/qrcode/main_public_key.json"
+  const val FEDERATION_DETAILS = "protocol/qrcode/federation_exchange.json"
 
   private val schemas: MutableMap<String, JsonSchema> = ConcurrentHashMap()
 

fe2-android/app/src/main/java/com/github/dedis/popstellar/model/qrcode/FederationDetails.kt

@@ -0,0 +1,33 @@
+package com.github.dedis.popstellar.model.qrcode
+
+import com.github.dedis.popstellar.model.Immutable
+import com.github.dedis.popstellar.model.network.method.message.data.federation.Challenge
+import com.github.dedis.popstellar.model.network.serializer.JsonUtils
+import com.google.gson.Gson
+import com.google.gson.annotations.SerializedName
+
+@Immutable
+class FederationDetails(
+    @field:SerializedName("lao_id") val laoId: String,
+    @field:SerializedName("server_address") val serverAddress: String,
+    @field:SerializedName("public_key") val publicKey: String,
+    val challenge: Challenge? = null
+) {
+
+  companion object {
+    /**
+     * Extract data from the given json string
+     *
+     * @param gson is used to parse the json string into the object
+     * @param json representation of the data
+     * @return the extracted data
+     * @throws com.google.gson.JsonParseException if the value cannot be parsed
+     */
+    @JvmStatic
+    fun extractFrom(gson: Gson, json: String?): FederationDetails {
+      JsonUtils.verifyJson(JsonUtils.FEDERATION_DETAILS, json)
+
+      return gson.fromJson(json, FederationDetails::class.java)
+    }
+  }
+}

fe2-android/app/src/main/java/com/github/dedis/popstellar/repository/LinkedOrganizationsRepository.kt

@@ -0,0 +1,45 @@
+package com.github.dedis.popstellar.repository
+
+import com.github.dedis.popstellar.model.network.method.message.data.federation.Challenge
+import javax.inject.Inject
+import javax.inject.Singleton
+
+/**
+ * This class is the repository of federation
+ *
+ * Its main purpose is to store received messages
+ */
+@Singleton
+class LinkedOrganizationsRepository @Inject constructor() {
+  private var challenge: Challenge? = null
+  private var onChallengeUpdatedCallback: ((Challenge) -> Unit)? = null
+  var otherLaoId: String? = null
+  var otherServerAddr: String? = null
+  var otherPublicKey: String? = null
+
+  /**
+   * Updates the challenge
+   *
+   * @param challenge the new Challenge
+   */
+  fun updateChallenge(challenge: Challenge) {
+    this.challenge = challenge
+    onChallengeUpdatedCallback?.invoke(challenge)
+  }
+
+  fun setOnChallengeUpdatedCallback(callback: (Challenge) -> Unit) {
+    onChallengeUpdatedCallback = callback
+  }
+
+  fun getChallenge(): Challenge? {
+    return challenge
+  }
+
+  fun flush() {
+    otherLaoId = null
+    otherServerAddr = null
+    otherPublicKey = null
+    challenge = null
+    onChallengeUpdatedCallback = null
+  }
+}

fe2-android/app/src/main/java/com/github/dedis/popstellar/ui/lao/LaoActivity.kt

@@ -29,6 +29,7 @@ import com.github.dedis.popstellar.ui.lao.event.eventlist.EventListFragment
 import com.github.dedis.popstellar.ui.lao.event.meeting.MeetingViewModel
 import com.github.dedis.popstellar.ui.lao.event.rollcall.RollCallViewModel
 import com.github.dedis.popstellar.ui.lao.federation.LinkedOrganizationsFragment
+import com.github.dedis.popstellar.ui.lao.federation.LinkedOrganizationsViewModel
 import com.github.dedis.popstellar.ui.lao.popcha.PoPCHAHomeFragment
 import com.github.dedis.popstellar.ui.lao.popcha.PoPCHAViewModel
 import com.github.dedis.popstellar.ui.lao.socialmedia.SocialMediaHomeFragment
@@ -434,6 +435,19 @@ class LaoActivity : AppCompatActivity() {
       return popCHAViewModel
     }
 
+    @JvmStatic
+    fun obtainLinkedOrganizationsViewModel(
+        activity: FragmentActivity,
+        laoId: String?
+    ): LinkedOrganizationsViewModel {
+      val linkedOrganizationsViewModel =
+          ViewModelProvider(activity)[LinkedOrganizationsViewModel::class.java]
+      if (laoId != null) {
+        linkedOrganizationsViewModel.setLaoId(laoId)
+      }
+      return linkedOrganizationsViewModel
+    }
+
     /**
      * Set the current fragment in the container of the activity
      *