Adding upstream version 2.4.1.upstream/2.4.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 323 insertions, 0 deletions

diff --git a/src/lib/asiolink/udp_socket.h b/src/lib/asiolink/udp_socket.h
new file mode 100644
index 0000000..fea8def
--- /dev/null
+++ b/src/lib/asiolink/udp_socket.h
@@ -0,0 +1,323 @@
+// Copyright (C) 2011-2022 Internet Systems Consortium, Inc. ("ISC")
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+#ifndef UDP_SOCKET_H
+#define UDP_SOCKET_H 1
+
+#ifndef BOOST_ASIO_HPP
+#error "asio.hpp must be included before including this, see asiolink.h as to why"
+#endif
+
+#include <netinet/in.h>
+#include <sys/socket.h>
+#include <unistd.h>             // for some IPC/network system calls
+
+#include <cstddef>
+
+#include <asiolink/io_asio_socket.h>
+#include <asiolink/io_endpoint.h>
+#include <asiolink/io_service.h>
+#include <asiolink/udp_endpoint.h>
+
+#include <exceptions/isc_assert.h>
+
+namespace isc {
+namespace asiolink {
+
+/// \brief The \c UDPSocket class is a concrete derived class of \c IOAsioSocket
+/// that represents a UDP socket.
+///
+/// \param C Callback type
+template <typename C>
+class UDPSocket : public IOAsioSocket<C> {
+private:
+    /// \brief Class is non-copyable
+    UDPSocket(const UDPSocket&);
+    UDPSocket& operator=(const UDPSocket&);
+
+public:
+    enum {
+        MIN_SIZE = 4096         // Minimum send and receive size
+    };
+
+    /// \brief Constructor from an ASIO UDP socket.
+    ///
+    /// \param socket The ASIO representation of the UDP socket.  It is assumed
+    ///        that the caller will open and close the socket, so these
+    ///        operations are a no-op for that socket.
+    UDPSocket(boost::asio::ip::udp::socket& socket);
+
+    /// \brief Constructor
+    ///
+    /// Used when the UDPSocket is being asked to manage its own internal
+    /// socket.  In this case, the open() and close() methods are used.
+    ///
+    /// \param service I/O Service object used to manage the socket.
+    UDPSocket(IOService& service);
+
+    /// \brief Destructor
+    virtual ~UDPSocket();
+
+    /// \brief Return file descriptor of underlying socket
+    virtual int getNative() const {
+#if BOOST_VERSION < 106600
+        return (socket_.native());
+#else
+        return (socket_.native_handle());
+#endif
+    }
+
+    /// \brief Return protocol of socket
+    virtual int getProtocol() const {
+        return (IPPROTO_UDP);
+    }
+
+    /// \brief Is "open()" synchronous?
+    ///
+    /// Indicates that the opening of a UDP socket is synchronous.
+    virtual bool isOpenSynchronous() const {
+        return true;
+    }
+
+    /// \brief Open Socket
+    ///
+    /// Opens the UDP socket.  This is a synchronous operation.
+    ///
+    /// \param endpoint Endpoint to which the socket will send data.  This is
+    ///        used to determine the address family that should be used for the
+    ///        underlying socket.
+    /// \param callback Unused as the operation is synchronous.
+    virtual void open(const IOEndpoint* endpoint, C& callback);
+
+    /// \brief Send Asynchronously
+    ///
+    /// Calls the underlying socket's async_send_to() method to send a packet of
+    /// data asynchronously to the remote endpoint.  The callback will be called
+    /// on completion.
+    ///
+    /// \param data Data to send
+    /// \param length Length of data to send
+    /// \param endpoint Target of the send
+    /// \param callback Callback object.
+    virtual void asyncSend(const void* data, size_t length,
+                           const IOEndpoint* endpoint, C& callback);
+
+    /// \brief Receive Asynchronously
+    ///
+    /// Calls the underlying socket's async_receive_from() method to read a
+    /// packet of data from a remote endpoint.  Arrival of the data is signalled
+    /// via a call to the callback function.
+    ///
+    /// \param data Buffer to receive incoming message
+    /// \param length Length of the data buffer
+    /// \param offset Offset into buffer where data is to be put
+    /// \param endpoint Source of the communication
+    /// \param callback Callback object
+    virtual void asyncReceive(void* data, size_t length, size_t offset,
+                              IOEndpoint* endpoint, C& callback);
+
+    /// \brief Process received data
+    ///
+    /// See the description of IOAsioSocket::receiveComplete for a complete
+    /// description of this method.
+    ///
+    /// \param staging Pointer to the start of the staging buffer.
+    /// \param length Amount of data in the staging buffer.
+    /// \param cumulative Amount of data received before the staging buffer is
+    ///        processed.
+    /// \param offset Unused.
+    /// \param expected unused.
+    /// \param outbuff Output buffer.  Data in the staging buffer is be copied
+    ///        to this output buffer in the call.
+    ///
+    /// \return Always true
+    virtual bool processReceivedData(const void* staging, size_t length,
+                                     size_t& cumulative, size_t& offset,
+                                     size_t& expected,
+                                     isc::util::OutputBufferPtr& outbuff);
+
+    /// \brief Cancel I/O On Socket
+    virtual void cancel();
+
+    /// \brief Close socket
+    virtual void close();
+
+
+private:
+    // Two variables to hold the socket - a socket and a pointer to it.  This
+    // handles the case where a socket is passed to the UDPSocket on
+    // construction, or where it is asked to manage its own socket.
+
+    /// Pointer to own socket
+    std::unique_ptr<boost::asio::ip::udp::socket> socket_ptr_;
+
+    // Socket
+    boost::asio::ip::udp::socket& socket_;
+
+    // True when socket is open
+    bool isopen_;
+};
+
+// Constructor - caller manages socket
+
+template <typename C>
+UDPSocket<C>::UDPSocket(boost::asio::ip::udp::socket& socket) :
+    socket_ptr_(), socket_(socket), isopen_(true)
+{
+}
+
+// Constructor - create socket on the fly
+
+template <typename C>
+UDPSocket<C>::UDPSocket(IOService& service) :
+    socket_ptr_(new boost::asio::ip::udp::socket(service.get_io_service())),
+    socket_(*socket_ptr_), isopen_(false)
+{
+}
+
+// Destructor.
+
+template <typename C>
+UDPSocket<C>::~UDPSocket()
+{
+}
+
+// Open the socket.
+
+template <typename C> void
+UDPSocket<C>::open(const IOEndpoint* endpoint, C&) {
+
+    // Ignore opens on already-open socket.  (Don't throw a failure because
+    // of uncertainties as to what precedes when using asynchronous I/O.)
+    // It also allows us a treat a passed-in socket in exactly the same way as
+    // a self-managed socket (in that we can call the open() and close() methods
+    // of this class).
+    if (!isopen_) {
+        if (endpoint->getFamily() == AF_INET) {
+            socket_.open(boost::asio::ip::udp::v4());
+        } else {
+            socket_.open(boost::asio::ip::udp::v6());
+        }
+        isopen_ = true;
+
+        // Ensure it can send and receive at least 4K buffers.
+        boost::asio::ip::udp::socket::send_buffer_size snd_size;
+        socket_.get_option(snd_size);
+        if (snd_size.value() < MIN_SIZE) {
+            snd_size = MIN_SIZE;
+            socket_.set_option(snd_size);
+        }
+
+        boost::asio::ip::udp::socket::receive_buffer_size rcv_size;
+        socket_.get_option(rcv_size);
+        if (rcv_size.value() < MIN_SIZE) {
+            rcv_size = MIN_SIZE;
+            socket_.set_option(rcv_size);
+        }
+    }
+}
+
+// Send a message.  Should never do this if the socket is not open, so throw
+// an exception if this is the case.
+
+template <typename C> void
+UDPSocket<C>::asyncSend(const void* data, size_t length,
+                        const IOEndpoint* endpoint, C& callback)
+{
+    if (isopen_) {
+
+        // Upconvert to a UDPEndpoint.  We need to do this because although
+        // IOEndpoint is the base class of UDPEndpoint and TCPEndpoint, it
+        // does not contain a method for getting at the underlying endpoint
+        // type - that is in the derived class and the two classes differ on
+        // return type.
+        isc_throw_assert(endpoint->getProtocol() == IPPROTO_UDP);
+        const UDPEndpoint* udp_endpoint =
+            static_cast<const UDPEndpoint*>(endpoint);
+
+        // ... and send the message.
+        socket_.async_send_to(boost::asio::buffer(data, length),
+            udp_endpoint->getASIOEndpoint(), callback);
+    } else {
+        isc_throw(SocketNotOpen,
+            "attempt to send on a UDP socket that is not open");
+    }
+}
+
+// Receive a message.   Should never do this if the socket is not open, so throw
+// an exception if this is the case.
+
+template <typename C> void
+UDPSocket<C>::asyncReceive(void* data, size_t length, size_t offset,
+                           IOEndpoint* endpoint, C& callback)
+{
+    if (isopen_) {
+
+        // Upconvert the endpoint again.
+        isc_throw_assert(endpoint->getProtocol() == IPPROTO_UDP);
+        UDPEndpoint* udp_endpoint = static_cast<UDPEndpoint*>(endpoint);
+
+        // Ensure we can write into the buffer
+        if (offset >= length) {
+            isc_throw(BufferOverflow, "attempt to read into area beyond end of "
+                                      "UDP receive buffer");
+        }
+        void* buffer_start = static_cast<void*>(static_cast<uint8_t*>(data) + offset);
+
+        // Issue the read
+        socket_.async_receive_from(boost::asio::buffer(buffer_start, length - offset),
+            udp_endpoint->getASIOEndpoint(), callback);
+    } else {
+        isc_throw(SocketNotOpen,
+            "attempt to receive from a UDP socket that is not open");
+    }
+}
+
+// Receive complete.  Just copy the data across to the output buffer and
+// update arguments as appropriate.
+
+template <typename C> bool
+UDPSocket<C>::processReceivedData(const void* staging, size_t length,
+                                  size_t& cumulative, size_t& offset,
+                                  size_t& expected,
+                                  isc::util::OutputBufferPtr& outbuff)
+{
+    // Set return values to what we should expect.
+    cumulative = length;
+    expected = length;
+    offset = 0;
+
+    // Copy data across
+    outbuff->writeData(staging, length);
+
+    // ... and mark that we have everything.
+    return (true);
+}
+
+// Cancel I/O on the socket.  No-op if the socket is not open.
+
+template <typename C> void
+UDPSocket<C>::cancel() {
+    if (isopen_) {
+        socket_.cancel();
+    }
+}
+
+// Close the socket down.  Can only do this if the socket is open and we are
+// managing it ourself.
+
+template <typename C> void
+UDPSocket<C>::close() {
+    if (isopen_ && socket_ptr_) {
+        socket_.close();
+        isopen_ = false;
+    }
+}
+
+} // namespace asiolink
+} // namespace isc
+
+#endif // UDP_SOCKET_H