avoid close srt stream if receive certain control packets without body

Author: pedroSG94

srt/src/main/java/com/pedro/srt/srt/SrtClient.kt

@@ -373,9 +373,6 @@ class SrtClient(private val connectChecker: ConnectChecker) {
       }
       is ControlPacket -> {
         when (srtPacket) {
-          is Handshake -> {
-            //never should happens, handshake is already done
-          }
           is KeepAlive -> {
             commandsManager.writeKeepAlive(socket)
           }
@@ -393,27 +390,24 @@ class SrtClient(private val connectChecker: ConnectChecker) {
             val lostRanges = srtPacket.getNakRanges()
             this.packetsLost += srtPacket.getLostCount()
             commandsManager.reSendPackets(lostRanges, socket)
-          }
-          is CongestionWarning -> {
-
           }
           is Shutdown -> {
             onMainThread {
               connectChecker.onConnectionFailed("Shutdown received from server")
             }
-          }
-          is Ack2 -> {
-            //never should happens
-          }
-          is DropReq -> {
-
           }
           is PeerError -> {
             val reason = srtPacket.errorCode
             onMainThread {
               connectChecker.onConnectionFailed("PeerError: $reason")
             }
           }
+          is Handshake -> {
+            //this never should happen, handshake is already done
+          }
+          is Ack2, is DropReq, is CongestionWarning -> {
+            //this never should happen
+          }
         }
       }
     }

srt/src/main/java/com/pedro/srt/srt/packets/control/Ack2.kt

@@ -37,7 +37,7 @@ class Ack2(
   fun read(input: InputStream) {
     super.readHeader(input)
     acknowledgementNumber = typeSpecificInformation
-    input.readUInt32()
+    if (input.available() >= 4) input.readUInt32()
   }
 
   override fun toString(): String {

srt/src/main/java/com/pedro/srt/srt/packets/control/CongestionWarning.kt

@@ -33,7 +33,7 @@ class CongestionWarning: ControlPacket(ControlType.CONGESTION_WARNING) {
 
   fun read(input: InputStream) {
     super.readHeader(input)
-    input.readUInt32()
+    if (input.available() >= 4) input.readUInt32()
   }
 
   override fun toString(): String {

srt/src/main/java/com/pedro/srt/srt/packets/control/DropReq.kt

@@ -48,6 +48,7 @@ class DropReq(
   }
 
   private fun readBody(input: InputStream) {
+    if (input.available() < 8) return
     firstPacketSequenceNumber = input.readUInt32() and 0x7FFFFFFF //31 bits
     lastPacketSequenceNumber = input.readUInt32() and 0x7FFFFFFF //31 bits
   }

srt/src/main/java/com/pedro/srt/srt/packets/control/KeepAlive.kt

@@ -33,7 +33,7 @@ class KeepAlive: ControlPacket(ControlType.KEEP_ALIVE) {
 
   fun read(input: InputStream) {
     super.readHeader(input)
-    input.readUInt32()
+    if (input.available() >= 4) input.readUInt32()
   }
 
   override fun toString(): String {

srt/src/main/java/com/pedro/srt/srt/packets/control/Shutdown.kt

@@ -33,7 +33,7 @@ class Shutdown: ControlPacket(ControlType.SHUTDOWN) {
 
   fun read(input: InputStream) {
     super.readHeader(input)
-    input.readUInt32()
+    if (input.available() >= 4) input.readUInt32()
   }
 
   override fun toString(): String {

srt/src/test/java/com/pedro/srt/srt/control/Ack2Test.kt

@@ -49,4 +49,15 @@ class Ack2Test {
     packet.read(ByteArrayInputStream(buffer))
     Utils.assertObjectEquals(packet, expectedPacket)
   }
+
+  @Test
+  fun `GIVEN a buffer without control info field WHEN read buffer as ack2 packet THEN get expected ack2 packet`() {
+    val buffer = byteArrayOf(-128, 6, 0, 0, 0, 0, 0, 5, 0, 0, 9, -60, 0, 0, 0, 64)
+    val expectedPacket = Ack2(
+      acknowledgementNumber = 5
+    )
+    val packet = Ack2()
+    packet.read(ByteArrayInputStream(buffer))
+    Utils.assertObjectEquals(packet, expectedPacket)
+  }
 }

srt/src/test/java/com/pedro/srt/srt/control/CongestionWarningTest.kt

@@ -46,4 +46,14 @@ class CongestionWarningTest {
 
     Utils.assertObjectEquals(expectedPacket, packet)
   }
+
+  @Test
+  fun `GIVEN a buffer without control info field WHEN read buffer as congestion warning packet THEN get expected congestion warning packet`() {
+    val buffer = byteArrayOf(-128, 4, 0, 0, 0, 0, 0, 0, 0, 0, 9, -60, 0, 0, 0, 64)
+    val expectedPacket = CongestionWarning()
+    val packet = CongestionWarning()
+    packet.read(ByteArrayInputStream(buffer))
+
+    Utils.assertObjectEquals(expectedPacket, packet)
+  }
 }

srt/src/test/java/com/pedro/srt/srt/control/DropReqTest.kt

@@ -54,4 +54,18 @@ class DropReqTest {
 
     Utils.assertObjectEquals(expectedPacket, packet)
   }
+
+  @Test
+  fun `GIVEN a truncated drop req buffer WHEN read buffer as drop req packet THEN discard sequence numbers`() {
+    val buffer = byteArrayOf(-128, 7, 0, 0, 0, 0, 0, 5, 0, 0, 9, -60, 0, 0, 0, 64, 0, 0, 0, 1)
+    val expectedPacket = DropReq(
+      messageNumber = 5,
+      firstPacketSequenceNumber = 0,
+      lastPacketSequenceNumber = 0
+    )
+    val packet = DropReq()
+    packet.read(ByteArrayInputStream(buffer))
+
+    Utils.assertObjectEquals(expectedPacket, packet)
+  }
 }

srt/src/test/java/com/pedro/srt/srt/control/KeepAliveTest.kt

@@ -46,4 +46,14 @@ class KeepAliveTest {
 
     Utils.assertObjectEquals(expectedPacket, packet)
   }
+
+  @Test
+  fun `GIVEN a buffer without control info field WHEN read buffer as keep alive packet THEN get expected keep alive packet`() {
+    val buffer = byteArrayOf(-128, 1, 0, 0, 0, 0, 0, 0, 0, 0, 9, -60, 0, 0, 0, 64)
+    val expectedPacket = KeepAlive()
+    val packet = KeepAlive()
+    packet.read(ByteArrayInputStream(buffer))
+
+    Utils.assertObjectEquals(expectedPacket, packet)
+  }
 }