p2p: check address length before parsing

Change-Id: Ic4576fe22b10fc2033cbcd7afe8bb201c57223e1

src/jamidht/p2p.cpp

@@ -425,7 +425,7 @@ private:
 
         IpAddr relay_addr;
         for (const auto& address: response_.addresses) {
-            if (!(relay_addr = address)) {
+            if (!(address.size() <= PJ_MAX_HOSTNAME && (relay_addr = address))) {
                 // Should be ICE SDP
                 // P2P File transfer. We received an ice SDP message:
                 auto sdp = parent_.parse_SDP(address, *ice);
@@ -727,7 +727,9 @@ DhtPeerConnector::Impl::answerToRequest(PeerConnectionMsg&& request,
     std::shared_ptr<IceTransport> ice;
     for (auto& ip: request.addresses) {
         try {
-            if (IpAddr(ip).isIpv4()) {
+            if (ip.size() <= PJ_MAX_HOSTNAME) {
+                IpAddr addr(ip);
+                if (addr.isIpv4()) {
                     if (!sendTurn) continue;
                     std::lock_guard<std::mutex> lock(turnMutex_);
                     if (turnAuthv4_) {
@@ -735,7 +737,8 @@ DhtPeerConnector::Impl::answerToRequest(PeerConnectionMsg&& request,
                         turnAuthv4_->permitPeer(ip);
                     }
                     JAMI_DBG() << account << "[CNX] authorized peer connection from " << ip;
-            } else if (IpAddr(ip).isIpv6()) {
+                    continue;
+                } else if (addr.isIpv6()) {
                     if (!sendTurn) continue;
                     std::lock_guard<std::mutex> lock(turnMutex_);
                     if (turnAuthv6_) {
@@ -743,7 +746,10 @@ DhtPeerConnector::Impl::answerToRequest(PeerConnectionMsg&& request,
                         turnAuthv6_->permitPeer(ip);
                     }
                     JAMI_DBG() << account << "[CNX] authorized peer connection from " << ip;
-            } else {
+                    continue;
+                }
+            }
+
             // P2P File transfer. We received an ice SDP message:
             JAMI_DBG() << account << "[CNX] receiving ICE session request";
             auto &iceTransportFactory = Manager::instance().getIceTransportFactory();
@@ -785,7 +791,6 @@ DhtPeerConnector::Impl::answerToRequest(PeerConnectionMsg&& request,
                 }
             } else
                 sendIce = true; // Ice started with success, we can use it.
-            }
         } catch (const std::exception& e) {
             JAMI_WARN() << account << "[CNX] ignored peer connection '" << ip << "', " << e.what();
         }