feat(oob): implicit invitations (#1348)

Signed-off-by: Ariel Gentile <[email protected]>

packages/core/src/modules/connections/DidExchangeProtocol.ts

@@ -26,6 +26,7 @@ import {
   PeerDidNumAlgo,
 } from '../dids'
 import { getKeyFromVerificationMethod } from '../dids/domain/key-type'
+import { tryParseDid } from '../dids/domain/parse'
 import { didKeyToInstanceOfKey } from '../dids/helpers'
 import { DidRecord, DidRepository } from '../dids/repository'
 import { OutOfBandRole } from '../oob/domain/OutOfBandRole'
@@ -104,7 +105,7 @@ export class DidExchangeProtocol {
     // Create message
     const label = params.label ?? agentContext.config.label
     const didDocument = await this.createPeerDidDoc(agentContext, this.routingToServices(routing))
-    const parentThreadId = outOfBandInvitation.id
+    const parentThreadId = outOfBandRecord.outOfBandInvitation.id
 
     const message = new DidExchangeRequestMessage({ label, parentThreadId, did: didDocument.id, goal, goalCode })
 
@@ -146,9 +147,13 @@ export class DidExchangeProtocol {
 
     const { message } = messageContext
 
-    // Check corresponding invitation ID is the request's ~thread.pthid
+    // Check corresponding invitation ID is the request's ~thread.pthid or pthid is a public did
     // TODO Maybe we can do it in handler, but that actually does not make sense because we try to find oob by parent thread ID there.
-    if (!message.thread?.parentThreadId || message.thread?.parentThreadId !== outOfBandRecord.getTags().invitationId) {
+    const parentThreadId = message.thread?.parentThreadId
+    if (
+      !parentThreadId ||
+      (!tryParseDid(parentThreadId) && parentThreadId !== outOfBandRecord.getTags().invitationId)
+    ) {
       throw new DidExchangeProblemReportError('Missing reference to invitation.', {
         problemCode: DidExchangeProblemReportReason.RequestNotAccepted,
       })
@@ -401,8 +406,8 @@ export class DidExchangeProtocol {
         problemCode: DidExchangeProblemReportReason.CompleteRejected,
       })
     }
-
-    if (!message.thread?.parentThreadId || message.thread?.parentThreadId !== outOfBandRecord.getTags().invitationId) {
+    const pthid = message.thread?.parentThreadId
+    if (!pthid || pthid !== outOfBandRecord.outOfBandInvitation.id) {
       throw new DidExchangeProblemReportError('Invalid or missing parent thread ID referencing to the invitation.', {
         problemCode: DidExchangeProblemReportReason.CompleteRejected,
       })

packages/core/src/modules/connections/handlers/ConnectionRequestHandler.ts

@@ -7,7 +7,9 @@ import type { ConnectionService } from '../services/ConnectionService'
 
 import { OutboundMessageContext } from '../../../agent/models'
 import { AriesFrameworkError } from '../../../error/AriesFrameworkError'
+import { tryParseDid } from '../../dids/domain/parse'
 import { ConnectionRequestMessage } from '../messages'
+import { HandshakeProtocol } from '../models'
 
 export class ConnectionRequestHandler implements MessageHandler {
   private connectionService: ConnectionService
@@ -32,16 +34,23 @@ export class ConnectionRequestHandler implements MessageHandler {
   }
 
   public async handle(messageContext: MessageHandlerInboundMessage<ConnectionRequestHandler>) {
-    const { connection, recipientKey, senderKey } = messageContext
+    const { agentContext, connection, recipientKey, senderKey, message } = messageContext
 
     if (!recipientKey || !senderKey) {
       throw new AriesFrameworkError('Unable to process connection request without senderVerkey or recipientKey')
     }
 
-    const outOfBandRecord = await this.outOfBandService.findCreatedByRecipientKey(
-      messageContext.agentContext,
-      recipientKey
-    )
+    const parentThreadId = message.thread?.parentThreadId
+
+    const outOfBandRecord =
+      parentThreadId && tryParseDid(parentThreadId)
+        ? await this.outOfBandService.createFromImplicitInvitation(agentContext, {
+            did: parentThreadId,
+            threadId: message.threadId,
+            recipientKey,
+            handshakeProtocols: [HandshakeProtocol.Connections],
+          })
+        : await this.outOfBandService.findCreatedByRecipientKey(agentContext, recipientKey)
 
     if (!outOfBandRecord) {
       throw new AriesFrameworkError(`Out-of-band record for recipient key ${recipientKey.fingerprint} was not found.`)

packages/core/src/modules/connections/handlers/DidExchangeCompleteHandler.ts

@@ -3,6 +3,7 @@ import type { OutOfBandService } from '../../oob/OutOfBandService'
 import type { DidExchangeProtocol } from '../DidExchangeProtocol'
 
 import { AriesFrameworkError } from '../../../error'
+import { tryParseDid } from '../../dids/domain/parse'
 import { OutOfBandState } from '../../oob/domain/OutOfBandState'
 import { DidExchangeCompleteMessage } from '../messages'
 import { HandshakeProtocol } from '../models'
@@ -32,12 +33,14 @@ export class DidExchangeCompleteHandler implements MessageHandler {
     }
 
     const { message } = messageContext
-    if (!message.thread?.parentThreadId) {
+    const parentThreadId = message.thread?.parentThreadId
+    if (!parentThreadId) {
       throw new AriesFrameworkError(`Message does not contain pthid attribute`)
     }
     const outOfBandRecord = await this.outOfBandService.findByCreatedInvitationId(
       messageContext.agentContext,
-      message.thread?.parentThreadId
+      parentThreadId,
+      tryParseDid(parentThreadId) ? message.threadId : undefined
     )
 
     if (!outOfBandRecord) {

packages/core/src/modules/connections/handlers/DidExchangeRequestHandler.ts

@@ -7,8 +7,10 @@ import type { DidExchangeProtocol } from '../DidExchangeProtocol'
 
 import { OutboundMessageContext } from '../../../agent/models'
 import { AriesFrameworkError } from '../../../error/AriesFrameworkError'
+import { tryParseDid } from '../../dids/domain/parse'
 import { OutOfBandState } from '../../oob/domain/OutOfBandState'
 import { DidExchangeRequestMessage } from '../messages'
+import { HandshakeProtocol } from '../models'
 
 export class DidExchangeRequestHandler implements MessageHandler {
   private didExchangeProtocol: DidExchangeProtocol
@@ -33,22 +35,28 @@ export class DidExchangeRequestHandler implements MessageHandler {
   }
 
   public async handle(messageContext: MessageHandlerInboundMessage<DidExchangeRequestHandler>) {
-    const { recipientKey, senderKey, message, connection } = messageContext
+    const { agentContext, recipientKey, senderKey, message, connection } = messageContext
 
     if (!recipientKey || !senderKey) {
       throw new AriesFrameworkError('Unable to process connection request without senderKey or recipientKey')
     }
 
-    if (!message.thread?.parentThreadId) {
+    const parentThreadId = message.thread?.parentThreadId
+
+    if (!parentThreadId) {
       throw new AriesFrameworkError(`Message does not contain 'pthid' attribute`)
     }
-    const outOfBandRecord = await this.outOfBandService.findByCreatedInvitationId(
-      messageContext.agentContext,
-      message.thread.parentThreadId
-    )
 
+    const outOfBandRecord = tryParseDid(parentThreadId)
+      ? await this.outOfBandService.createFromImplicitInvitation(agentContext, {
+          did: parentThreadId,
+          threadId: message.threadId,
+          recipientKey,
+          handshakeProtocols: [HandshakeProtocol.DidExchange],
+        })
+      : await this.outOfBandService.findByCreatedInvitationId(agentContext, parentThreadId)
     if (!outOfBandRecord) {
-      throw new AriesFrameworkError(`OutOfBand record for message ID ${message.thread?.parentThreadId} not found!`)
+      throw new AriesFrameworkError(`OutOfBand record for message ID ${parentThreadId} not found!`)
     }
 
     if (connection && !outOfBandRecord.reusable) {

packages/core/src/modules/connections/services/ConnectionService.ts

@@ -121,7 +121,7 @@ export class ConnectionService {
 
     connectionRequest.setThread({
       threadId: connectionRequest.threadId,
-      parentThreadId: outOfBandInvitation.id,
+      parentThreadId: outOfBandRecord.outOfBandInvitation.id,
     })
 
     const connectionRecord = await this.createConnection(agentContext, {

packages/core/src/modules/oob/OutOfBandApi.ts

@@ -67,7 +67,7 @@ export interface CreateLegacyInvitationConfig {
   routing?: Routing
 }
 
-export interface ReceiveOutOfBandInvitationConfig {
+interface BaseReceiveOutOfBandInvitationConfig {
   label?: string
   alias?: string
   imageUrl?: string
@@ -76,6 +76,15 @@ export interface ReceiveOutOfBandInvitationConfig {
   reuseConnection?: boolean
   routing?: Routing
   acceptInvitationTimeoutMs?: number
+  isImplicit?: boolean
+}
+
+export type ReceiveOutOfBandInvitationConfig = Omit<BaseReceiveOutOfBandInvitationConfig, 'isImplicit'>
+
+export interface ReceiveOutOfBandImplicitInvitationConfig
+  extends Omit<BaseReceiveOutOfBandInvitationConfig, 'isImplicit' | 'reuseConnection'> {
+  did: string
+  handshakeProtocols?: HandshakeProtocol[]
 }
 
 @injectable()
@@ -321,6 +330,44 @@ export class OutOfBandApi {
   public async receiveInvitation(
     invitation: OutOfBandInvitation | ConnectionInvitationMessage,
     config: ReceiveOutOfBandInvitationConfig = {}
+  ): Promise<{ outOfBandRecord: OutOfBandRecord; connectionRecord?: ConnectionRecord }> {
+    return this._receiveInvitation(invitation, config)
+  }
+
+  /**
+   * Creates inbound out-of-band record from an implicit invitation, given as a public DID the agent
+   * should be capable of resolving. It automatically passes out-of-band invitation for further
+   * processing to `acceptInvitation` method. If you don't want to do that you can set
+   * `autoAcceptInvitation` attribute in `config` parameter to `false` and accept the message later by
+   * calling `acceptInvitation`.
+   *
+   * It supports both OOB (Aries RFC 0434: Out-of-Band Protocol 1.1) and Connection Invitation
+   * (0160: Connection Protocol). Handshake protocol to be used depends on handshakeProtocols
+   * (DID Exchange by default)
+   *
+   * Agent role: receiver (invitee)
+   *
+   * @param config config for creating and handling invitation
+   *
+   * @returns out-of-band record and connection record if one has been created.
+   */
+  public async receiveImplicitInvitation(config: ReceiveOutOfBandImplicitInvitationConfig) {
+    const invitation = new OutOfBandInvitation({
+      id: config.did,
+      label: config.label ?? '',
+      services: [config.did],
+      handshakeProtocols: config.handshakeProtocols ?? [HandshakeProtocol.DidExchange],
+    })
+
+    return this._receiveInvitation(invitation, { ...config, isImplicit: true })
+  }
+
+  /**
+   * Internal receive invitation method, for both explicit and implicit OOB invitations
+   */
+  private async _receiveInvitation(
+    invitation: OutOfBandInvitation | ConnectionInvitationMessage,
+    config: BaseReceiveOutOfBandInvitationConfig = {}
   ): Promise<{ outOfBandRecord: OutOfBandRecord; connectionRecord?: ConnectionRecord }> {
     // Convert to out of band invitation if needed
     const outOfBandInvitation =
@@ -344,15 +391,19 @@ export class OutOfBandApi {
       )
     }
 
-    // Make sure we haven't received this invitation before. (it's fine if we created it, that means we're connecting with ourselves
-    let [outOfBandRecord] = await this.outOfBandService.findAllByQuery(this.agentContext, {
-      invitationId: outOfBandInvitation.id,
-      role: OutOfBandRole.Receiver,
-    })
-    if (outOfBandRecord) {
-      throw new AriesFrameworkError(
-        `An out of band record with invitation ${outOfBandInvitation.id} has already been received. Invitations should have a unique id.`
-      )
+    // Make sure we haven't received this invitation before
+    // It's fine if we created it (means that we are connnecting to ourselves) or if it's an implicit
+    // invitation (it allows to connect multiple times to the same public did)
+    if (!config.isImplicit) {
+      const existingOobRecordsFromThisId = await this.outOfBandService.findAllByQuery(this.agentContext, {
+        invitationId: outOfBandInvitation.id,
+        role: OutOfBandRole.Receiver,
+      })
+      if (existingOobRecordsFromThisId.length > 0) {
+        throw new AriesFrameworkError(
+          `An out of band record with invitation ${outOfBandInvitation.id} has already been received. Invitations should have a unique id.`
+        )
+      }
     }
 
     const recipientKeyFingerprints: string[] = []
@@ -374,7 +425,7 @@ export class OutOfBandApi {
       }
     }
 
-    outOfBandRecord = new OutOfBandRecord({
+    const outOfBandRecord = new OutOfBandRecord({
       role: OutOfBandRole.Receiver,
       state: OutOfBandState.Initial,
       outOfBandInvitation: outOfBandInvitation,
@@ -430,11 +481,12 @@ export class OutOfBandApi {
 
     const { outOfBandInvitation } = outOfBandRecord
     const { label, alias, imageUrl, autoAcceptConnection, reuseConnection, routing } = config
-    const { handshakeProtocols } = outOfBandInvitation
     const services = outOfBandInvitation.getServices()
     const messages = outOfBandInvitation.getRequests()
     const timeoutMs = config.timeoutMs ?? 20000
 
+    const { handshakeProtocols } = outOfBandInvitation
+
     const existingConnection = await this.findExistingConnection(outOfBandInvitation)
 
     await this.outOfBandService.updateState(this.agentContext, outOfBandRecord, OutOfBandState.PrepareResponse)

packages/core/src/modules/oob/OutOfBandService.ts

@@ -1,22 +1,32 @@
 import type { HandshakeReusedEvent, OutOfBandStateChangedEvent } from './domain/OutOfBandEvents'
-import type { OutOfBandRecord } from './repository'
 import type { AgentContext } from '../../agent'
 import type { InboundMessageContext } from '../../agent/models/InboundMessageContext'
 import type { Key } from '../../crypto'
 import type { Query } from '../../storage/StorageService'
 import type { ConnectionRecord } from '../connections'
+import type { HandshakeProtocol } from '../connections/models'
 
 import { EventEmitter } from '../../agent/EventEmitter'
 import { AriesFrameworkError } from '../../error'
 import { injectable } from '../../plugins'
 import { JsonTransformer } from '../../utils'
+import { DidsApi } from '../dids'
+import { parseDid } from '../dids/domain/parse'
 
 import { OutOfBandEventTypes } from './domain/OutOfBandEvents'
 import { OutOfBandRole } from './domain/OutOfBandRole'
 import { OutOfBandState } from './domain/OutOfBandState'
-import { HandshakeReuseMessage } from './messages'
+import { HandshakeReuseMessage, OutOfBandInvitation } from './messages'
 import { HandshakeReuseAcceptedMessage } from './messages/HandshakeReuseAcceptedMessage'
-import { OutOfBandRepository } from './repository'
+import { OutOfBandRecord, OutOfBandRepository } from './repository'
+
+export interface CreateFromImplicitInvitationConfig {
+  did: string
+  threadId: string
+  handshakeProtocols: HandshakeProtocol[]
+  autoAcceptConnection?: boolean
+  recipientKey: Key
+}
 
 @injectable()
 export class OutOfBandService {
@@ -28,6 +38,51 @@ export class OutOfBandService {
     this.eventEmitter = eventEmitter
   }
 
+  /**
+   * Creates an Out of Band record from a Connection/DIDExchange request started by using
+   * a publicly resolvable DID this agent can control
+   */
+  public async createFromImplicitInvitation(
+    agentContext: AgentContext,
+    config: CreateFromImplicitInvitationConfig
+  ): Promise<OutOfBandRecord> {
+    const { did, threadId, handshakeProtocols, autoAcceptConnection, recipientKey } = config
+
+    // Verify it is a valid did and it is present in the wallet
+    const publicDid = parseDid(did)
+    const didsApi = agentContext.dependencyManager.resolve(DidsApi)
+    const [createdDid] = await didsApi.getCreatedDids({ did: publicDid.did })
+    if (!createdDid) {
+      throw new AriesFrameworkError(`Referenced public did ${did} not found.`)
+    }
+
+    // Recreate an 'implicit invitation' matching the parameters used by the invitee when
+    // initiating the flow
+    const outOfBandInvitation = new OutOfBandInvitation({
+      id: did,
+      label: '',
+      services: [did],
+      handshakeProtocols,
+    })
+
+    outOfBandInvitation.setThread({ threadId })
+
+    const outOfBandRecord = new OutOfBandRecord({
+      role: OutOfBandRole.Sender,
+      state: OutOfBandState.AwaitResponse,
+      reusable: true,
+      autoAcceptConnection: autoAcceptConnection ?? false,
+      outOfBandInvitation,
+      tags: {
+        recipientKeyFingerprints: [recipientKey.fingerprint],
+      },
+    })
+
+    await this.save(agentContext, outOfBandRecord)
+    this.emitStateChangedEvent(agentContext, outOfBandRecord, null)
+    return outOfBandRecord
+  }
+
   public async processHandshakeReuse(messageContext: InboundMessageContext<HandshakeReuseMessage>) {
     const reuseMessage = messageContext.message
     const parentThreadId = reuseMessage.thread?.parentThreadId
@@ -172,10 +227,11 @@ export class OutOfBandService {
     })
   }
 
-  public async findByCreatedInvitationId(agentContext: AgentContext, createdInvitationId: string) {
+  public async findByCreatedInvitationId(agentContext: AgentContext, createdInvitationId: string, threadId?: string) {
     return this.outOfBandRepository.findSingleByQuery(agentContext, {
       invitationId: createdInvitationId,
       role: OutOfBandRole.Sender,
+      threadId,
     })
   }