feat: support setting ICE ufrag and pwd, and missing config values

Updates the implementation to match the latest libdatachannel with
features for setting ICE ufrag/pwd and reading the remote cert
fingerprint.

Also adds pass-through for missing config values.

Author: achingbrain

API.md

@@ -16,12 +16,19 @@ export interface RtcConfig {
     bindAddress?: string;
     enableIceTcp?: boolean;
     enableIceUdpMux?: boolean;
+    disableAutoNegotiation?: boolean;
+    disableFingerprintVerification?: boolean;
+    disableAutoGathering?: boolean;
+    forceMediaTransport?: boolean;
     portRangeBegin?: number;
     portRangeEnd?: number;
     maxMessageSize?: number;
     mtu?: number;
     iceTransportPolicy?: TransportPolicy;
     disableFingerprintVerification?: boolean;
+    certificatePemFile?: string;
+    keyPemFile?: string;
+    keyPemPass?: string;
 }
 
 export const enum RelayType {
@@ -69,6 +76,27 @@ export const enum DescriptionType {
 }
 ```
 
+**setLocalDescription: (sdp: string, init?: LocalDescriptionInit) => void**
+
+Set Local Description and optionally the ICE ufrag/pwd to use. These should not
+be set as they will be generated automatically as per the spec.
+```
+export interface LocalDescriptionInit {
+    iceUfrag?: string;
+    icePwd?: string;
+}
+```
+
+**remoteFingerprint: () => CertificateFingerprint**
+
+Returns the certificate fingerprint used by the remote peer
+```
+export interface CertificateFingerprint {
+    value: string;
+    algorithm: 'sha-1' | 'sha-224' | 'sha-256' | 'sha-384' | 'sha-512' | 'md5' | 'md2';
+}
+```
+
 **addRemoteCandidate: (candidate: string, mid: string) => void**
 
 Add remote candidate info

src/cpp/peer-connection-wrapper.cpp

@@ -41,6 +41,7 @@ Napi::Object PeerConnectionWrapper::Init(Napi::Env env, Napi::Object exports)
             InstanceMethod("setRemoteDescription", &PeerConnectionWrapper::setRemoteDescription),
             InstanceMethod("localDescription", &PeerConnectionWrapper::localDescription),
             InstanceMethod("remoteDescription", &PeerConnectionWrapper::remoteDescription),
+            InstanceMethod("remoteFingerprint", &PeerConnectionWrapper::remoteFingerprint),
             InstanceMethod("addRemoteCandidate", &PeerConnectionWrapper::addRemoteCandidate),
             InstanceMethod("createDataChannel", &PeerConnectionWrapper::createDataChannel),
             InstanceMethod("addTrack", &PeerConnectionWrapper::addTrack),
@@ -214,6 +215,10 @@ PeerConnectionWrapper::PeerConnectionWrapper(const Napi::CallbackInfo &info) : N
     if (config.Get("disableAutoNegotiation").IsBoolean())
         rtcConfig.disableAutoNegotiation = config.Get("disableAutoNegotiation").As<Napi::Boolean>();
 
+    // disableAutoGathering option
+    if (config.Get("disableAutoGathering").IsBoolean())
+        rtcConfig.disableAutoGathering = config.Get("disableAutoGathering").As<Napi::Boolean>();
+
     // forceMediaTransport option
     if (config.Get("forceMediaTransport").IsBoolean())
         rtcConfig.forceMediaTransport = config.Get("forceMediaTransport").As<Napi::Boolean>();
@@ -251,6 +256,17 @@ PeerConnectionWrapper::PeerConnectionWrapper(const Napi::CallbackInfo &info) : N
         rtcConfig.disableFingerprintVerification = config.Get("disableFingerprintVerification").As<Napi::Boolean>();
     }
 
+    // Specify certificate to use if set
+    if (config.Get("certificatePemFile").IsString()) {
+        rtcConfig.certificatePemFile = config.Get("certificatePemFile").As<Napi::String>().ToString();
+    }
+    if (config.Get("keyPemFile").IsString()) {
+        rtcConfig.keyPemFile = config.Get("keyPemFile").As<Napi::String>().ToString();
+    }
+    if (config.Get("keyPemPass").IsString()) {
+        rtcConfig.keyPemPass = config.Get("keyPemPass").As<Napi::String>().ToString();
+    }
+
     // Create peer-connection
     try
     {
@@ -331,6 +347,7 @@ void PeerConnectionWrapper::setLocalDescription(const Napi::CallbackInfo &info)
     }
 
     rtc::Description::Type type = rtc::Description::Type::Unspec;
+    rtc::LocalDescriptionInit init;
 
     // optional
     if (length > 0)
@@ -356,7 +373,29 @@ void PeerConnectionWrapper::setLocalDescription(const Napi::CallbackInfo &info)
             type = rtc::Description::Type::Rollback;
     }
 
-    mRtcPeerConnPtr->setLocalDescription(type);
+    // optional
+    if (length > 1)
+    {
+        PLOG_DEBUG << "setLocalDescription() called with LocalDescriptionInit";
+
+        if (info[1].IsObject())
+        {
+            PLOG_DEBUG << "setLocalDescription() called with LocalDescriptionInit as object";
+            Napi::Object obj = info[1].As<Napi::Object>();
+
+            if (obj.Get("iceUfrag").IsString()) {
+                PLOG_DEBUG << "setLocalDescription() has ufrag";
+                init.iceUfrag = obj.Get("iceUfrag").As<Napi::String>();
+            }
+
+            if (obj.Get("icePwd").IsString()) {
+                PLOG_DEBUG << "setLocalDescription() has password";
+                init.icePwd = obj.Get("icePwd").As<Napi::String>();
+            }
+        }
+    }
+
+    mRtcPeerConnPtr->setLocalDescription(type, init);
 }
 
 void PeerConnectionWrapper::setRemoteDescription(const Napi::CallbackInfo &info)
@@ -1002,7 +1041,34 @@ Napi::Value PeerConnectionWrapper::maxMessageSize(const Napi::CallbackInfo &info
 
     try
     {
-        return Napi::Number::New(env, mRtcPeerConnPtr->remoteMaxMessageSize());
+        return Napi::Array::New(env, mRtcPeerConnPtr->remoteMaxMessageSize());
+    }
+    catch (std::exception &ex)
+    {
+        Napi::Error::New(env, std::string("libdatachannel error: ") + ex.what()).ThrowAsJavaScriptException();
+        return Napi::Number::New(info.Env(), 0);
+    }
+}
+
+Napi::Value PeerConnectionWrapper::remoteFingerprint(const Napi::CallbackInfo &info)
+{
+    PLOG_DEBUG << "remoteFingerprints() called";
+    Napi::Env env = info.Env();
+
+    if (!mRtcPeerConnPtr)
+    {
+        return Napi::Number::New(info.Env(), 0);
+    }
+
+    try
+    {
+        auto fingerprint = mRtcPeerConnPtr->remoteFingerprint();
+
+        Napi::Object fingerprintObject = Napi::Object::New(env);
+        fingerprintObject.Set("value", fingerprint.value);
+        fingerprintObject.Set("algorithm", rtc::CertificateFingerprint::AlgorithmIdentifier(fingerprint.algorithm));
+
+        return fingerprintObject;
     }
     catch (std::exception &ex)
     {

src/cpp/peer-connection-wrapper.h

@@ -33,6 +33,7 @@ class PeerConnectionWrapper : public Napi::ObjectWrap<PeerConnectionWrapper>
   Napi::Value iceState(const Napi::CallbackInfo &info);
   Napi::Value signalingState(const Napi::CallbackInfo &info);
   Napi::Value gatheringState(const Napi::CallbackInfo &info);
+  Napi::Value remoteFingerprint(const Napi::CallbackInfo &info);
 
   // Callbacks
   void onLocalDescription(const Napi::CallbackInfo &info);

src/lib/index.ts

@@ -1,7 +1,7 @@
 import nodeDataChannel from './node-datachannel';
 import _DataChannelStream from './datachannel-stream';
 import { WebSocketServer } from './websocket-server';
-import { Channel, DataChannelInitConfig, DescriptionType, Direction, LogLevel, RtcConfig, RTCIceConnectionState, RTCIceGatheringState, RTCPeerConnectionState, RTCSignalingState, SctpSettings, SelectedCandidateInfo } from './types';
+import { CertificateFingerprint, Channel, DataChannelInitConfig, DescriptionType, Direction, LocalDescriptionInit, LogLevel, RtcConfig, RTCIceConnectionState, RTCIceGatheringState, RTCPeerConnectionState, RTCSignalingState, SctpSettings, SelectedCandidateInfo } from './types';
 import { WebSocket } from './websocket';
 
 export function preload(): void { nodeDataChannel.preload(); }
@@ -113,10 +113,11 @@ export const DataChannel: {
 
 export interface PeerConnection {
     close(): void;
-    setLocalDescription(type?: DescriptionType): void;
+    setLocalDescription(type?: DescriptionType, init?: LocalDescriptionInit): void;
     setRemoteDescription(sdp: string, type: DescriptionType): void;
     localDescription(): { type: DescriptionType; sdp: string } | null;
     remoteDescription(): { type: DescriptionType; sdp: string } | null;
+    remoteFingerprint(): CertificateFingerprint;
     addRemoteCandidate(candidate: string, mid: string): void;
     createDataChannel(label: string, config?: DataChannelInitConfig): DataChannel;
     addTrack(media: Video | Audio): Track;

src/lib/types.ts

@@ -77,6 +77,10 @@ export interface RtcConfig {
     mtu?: number;
     iceTransportPolicy?: TransportPolicy;
     disableFingerprintVerification?: boolean;
+    disableAutoGathering?: boolean;
+    certificatePemFile?: string;
+    keyPemFile?: string;
+    keyPemPass?: string;
 }
 
 // Lowercase to match the description type string from libdatachannel
@@ -97,6 +101,10 @@ export type RTCIceGathererState = "complete" | "gathering" | "new";
 export type RTCIceGatheringState = "complete" | "gathering" | "new";
 export type RTCSignalingState = "closed" | "have-local-offer" | "have-local-pranswer" | "have-remote-offer" | "have-remote-pranswer" | "stable";
 
+export interface LocalDescriptionInit {
+    iceUfrag?: string;
+    icePwd?: string;
+}
 
 export interface DataChannelInitConfig {
     protocol?: string;
@@ -107,6 +115,17 @@ export interface DataChannelInitConfig {
     maxRetransmits?: number; // Reliability
 }
 
+export interface CertificateFingerprint {
+    /**
+     * @see https://developer.mozilla.org/en-US/docs/Web/API/RTCCertificate/getFingerprints#value
+     */
+    value: string;
+    /**
+     * @see https://developer.mozilla.org/en-US/docs/Web/API/RTCCertificate/getFingerprints#algorithm
+     */
+    algorithm: 'sha-1' | 'sha-224' | 'sha-256' | 'sha-384' | 'sha-512' | 'md5' | 'md2';
+}
+
 export interface SelectedCandidateInfo {
     address: string;
     port: number;