Failed to send an ICMP packet through socket on Android API 22 (Lollipop)

I wrote a small app that pings a remote server by sending ICMP packets using sockets (Android's Os package). I tested it on the API 28 emulator and it worked, but it does not work on API 22 (Android 5.1 Lollipop). I tested it on the VD as well as on my smartphone (same old API) with the same negative result

android.system.ErrnoException: sendto failed: EINVAL (Invalid argument)

I debugged the app on different API versions and the only difference I noticed that ByteBuffer.wrap() produces ByteArrayBuffer instance on API 22 and HeapArrayBuffer instance on newer versions. The payload itself seems to be the same.

Here is the code sample (simplified). Also, there is a test application available: https://github.com/alexeysirenko/android-sockets-icmp-ping-test You could try to launch it on the different emulators (API 22 and >22) and see the difference

private val timeoutMs = 5000
private val delayMs = 500L
private val ECHO_PORT =  80
private val POLLIN = (if (OsConstants.POLLIN == 0) 1 else OsConstants.POLLIN).toShort()

fun ping(host: String): Unit {
    val inetAddress: InetAddress = InetAddress.getByName(host)
    if (inetAddress is Inet6Address) throw Exception("IPv6 implementation omitted for simplicity")
    val proto = OsConstants.IPPROTO_ICMP
    val inet = OsConstants.AF_INET
    val type = PacketBuilder.TYPE_ICMP_V4
    val socketFileDescriptor = Os.socket(inet, OsConstants.SOCK_DGRAM, proto)
    if (!socketFileDescriptor.valid()) throw Exception("Socket descriptor is invalid")    
    var sequenceNumber: Short = 0
    for (i in 0..2) {
        sequenceNumber++
        val echoPacketBuilder =
            PacketBuilder(type, "foobarbazquok".toByteArray())
                .withSequenceNumber(sequenceNumber)
        val buffer = echoPacketBuilder.build()

        /**
         * This is the command that throws an exception
         */
        val bytesSent = Os.sendto(socketFileDescriptor, buffer,0, buffer.size, 0, inetAddress, ECHO_PORT)

        // Response processing code omitted
    }
}

class PacketBuilder(val type: Byte, val payload: ByteArray, val sequenceNumber: Short = 0, val identifier: Short = 0xDBB) {
    private val MAX_PAYLOAD = 65507
    private val CODE: Byte = 0

    init {
        if (payload.size > MAX_PAYLOAD) throw Exception("Payload limited to $MAX_PAYLOAD")
    }

    fun build(): ByteArray {
        val buffer = ByteArray(8 + payload.size)
        val byteBuffer = ByteBuffer.wrap(buffer)

        byteBuffer.put(type)
        byteBuffer.put(CODE)
        val checkPos = byteBuffer.position()
        byteBuffer.position(checkPos + 2)
        byteBuffer.putShort(identifier)
        byteBuffer.putShort(sequenceNumber)
        byteBuffer.put(payload)
        byteBuffer.putShort(checkPos, checksum(buffer))
        byteBuffer.flip()
        return buffer
    }

    fun withSequenceNumber(sequenceNumber: Short): PacketBuilder {
        return PacketBuilder(type, payload, sequenceNumber, identifier)
    }

    /**
     * RFC 1071 checksum
     */
    private fun checksum(data: ByteArray): Short {
        var sum = 0
        // High bytes (even indices)
        for (i in 0 until data.size step 2) {
            sum += data[i].and(0xFF.toByte()).toInt() shl 8
            sum = (sum and 0xFFFF) + (sum shr 16)
        }

        // Low bytes (odd indices)
        for (i in 1 until data.size step 2) {
            sum += data[i] and 0xFF.toByte()
            sum = (sum and 0xFFFF) + (sum shr 16)
        }

        sum = (sum and 0xFFFF) + (sum shr 16)
        return (sum xor 0xFFFF).toShort()
    }

    companion object {
        val TYPE_ICMP_V4: Byte = 8
    }
}

If my code is incorrect then I'd expect the same error on all platforms, but as I said it does work on all APIs newer than 22 and I do not know exactly what causes this issue

from Failed to send an ICMP packet through socket on Android API 22 (Lollipop)