Adding upstream version 2.2.0.upstream/2.2.0upstream

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

1 files changed, 246 insertions, 0 deletions

diff --git a/src/lib/asiodns/io_fetch.h b/src/lib/asiodns/io_fetch.h
new file mode 100644
index 0000000..4b247ab
--- /dev/null
+++ b/src/lib/asiodns/io_fetch.h
@@ -0,0 +1,246 @@
+// Copyright (C) 2010-2021 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 IO_FETCH_H
+#define IO_FETCH_H 1
+
+#include <config.h>
+
+#include <boost/shared_array.hpp>
+#include <boost/shared_ptr.hpp>
+#include <boost/date_time/posix_time/posix_time_types.hpp>
+
+// We want to use coroutine.hpp from the system's boost headers if possible.
+// However, very old Boost versions (provided by RHEL 7 or CentOS 7) didn't have
+// this header. So we can resort to our bundled version, but only if necessary.
+#ifdef HAVE_BOOST_ASIO_COROUTINE_HPP
+#include <boost/asio/coroutine.hpp>
+#else
+#include <ext/coroutine/coroutine.hpp>
+#endif
+
+#include <boost/system/error_code.hpp>
+#include <asiolink/io_address.h>
+#include <asiolink/io_service.h>
+
+#include <util/buffer.h>
+#include <dns/question.h>
+#include <dns/message.h>
+
+namespace isc {
+namespace asiodns {
+
+// Forward declarations
+struct IOFetchData;
+
+/// \brief Upstream Fetch Processing
+///
+/// IOFetch is the class used to send upstream fetches and to handle responses.
+///
+/// \param E Endpoint type to use.
+
+class IOFetch : public boost::asio::coroutine {
+public:
+    /// \brief Protocol to use on the fetch
+    enum Protocol {
+        UDP = 0,
+        TCP = 1
+    };
+
+    /// \brief Origin of Asynchronous I/O Call
+    ///
+    /// Indicates what initiated an asynchronous I/O call and used in deciding
+    /// what error message to output if the I/O fails.
+    enum Origin {
+        NONE = 0,           ///< No asynchronous call outstanding
+        OPEN = 1,
+        SEND = 2,
+        RECEIVE = 3,
+        CLOSE = 4
+    };
+
+    /// \brief Result of Upstream Fetch
+    ///
+    /// Note that this applies to the status of I/Os in the fetch - a fetch
+    /// that resulted in a packet being received from the server is a SUCCESS,
+    /// even if the contents of the packet indicate that some error occurred.
+    enum Result {
+        SUCCESS = 0,        ///< Success, fetch completed
+        TIME_OUT = 1,       ///< Failure, fetch timed out
+        STOPPED = 2,        ///< Control code, fetch has been stopped
+        NOTSET = 3          ///< For testing, indicates value not set
+    };
+
+    // The next enum is a "trick" to allow constants to be defined in a class
+    // declaration.
+
+    /// \brief Integer Constants
+    enum {
+        STAGING_LENGTH = 8192   ///< Size of staging buffer
+    };
+
+    /// \brief I/O Fetch Callback
+    ///
+    /// Class of callback object for when the fetch itself has completed - an
+    /// object of this class is passed to the IOFetch constructor and its
+    /// operator() method called when the fetch completes.
+    ///
+    /// Note the difference between the two operator() methods:
+    /// - IOFetch::operator() callback is called when an asynchronous I/O has
+    ///   completed.
+    /// - IOFetch::Callback::operator() is called when an upstream fetch - which
+    ///   may have involved several asynchronous I/O operations - has completed.
+    ///
+    /// This is an abstract class.
+    class Callback {
+    public:
+        /// \brief Default Constructor
+        Callback()
+        {}
+
+        /// \brief Virtual Destructor
+        virtual ~Callback()
+        {}
+
+        /// \brief Callback method
+        ///
+        /// This is the method called when the fetch completes.
+        ///
+        /// \param result Result of the fetch
+        virtual void operator()(Result result) = 0;
+    };
+
+    /// \brief Constructor.
+    ///
+    /// Creates the object that will handle the upstream fetch.
+    ///
+    /// \param protocol Fetch protocol, either IOFetch::TCP or IOFetch::UDP
+    /// \param service I/O Service object to handle the asynchronous
+    ///        operations.
+    /// \param question DNS question to send to the upstream server.
+    /// \param address IP address of upstream server
+    /// \param port Port to which to connect on the upstream server
+    /// \param buff Output buffer into which the response (in wire format)
+    ///        is written (if a response is received).
+    /// \param cb Callback object containing the callback to be called when we
+    ///        terminate.  The caller is responsible for managing this object
+    ///        and deleting it if necessary.
+    /// \param wait Timeout for the fetch (in ms).  The default value of
+    ///        -1 indicates no timeout.
+    /// \param edns true if the request should be EDNS. The default value is
+    ///        true.
+    IOFetch(Protocol protocol, isc::asiolink::IOService& service,
+            const isc::dns::Question& question,
+            const isc::asiolink::IOAddress& address,
+            uint16_t port, isc::util::OutputBufferPtr& buff, Callback* cb,
+            int wait = -1,
+            bool edns = true);
+
+    /// \brief Constructor
+    ///  This constructor has one parameter "query_message", which
+    ///  is the shared_ptr to a full query message. It's different
+    ///  with above constructor which has only question section. All
+    ///  other parameters are same.
+    ///
+    /// \param protocol Fetch protocol, either IOFetch::TCP or IOFetch::UDP
+    /// \param service I/O Service object to handle the asynchronous
+    ///        operations.
+    /// \param query_message the shared_ptr to a full query message
+    ///        got from a query client.
+    /// \param address IP address of upstream server
+    /// \param port Port to which to connect on the upstream server
+    /// \param buff Output buffer into which the response (in wire format)
+    ///        is written (if a response is received).
+    /// \param cb Callback object containing the callback to be called when we
+    ///        terminate.  The caller is responsible for managing this object
+    ///        and deleting it if necessary.
+    /// \param wait Timeout for the fetch (in ms).  The default value of
+    ///        -1 indicates no timeout.
+    IOFetch(Protocol protocol, isc::asiolink::IOService& service,
+            isc::dns::ConstMessagePtr query_message,
+            const isc::asiolink::IOAddress& address,
+            uint16_t port, isc::util::OutputBufferPtr& buff, Callback* cb,
+            int wait = -1);
+
+    /// \brief Constructor.
+    ///
+    /// Creates the object that will handle the upstream fetch.
+    ///
+    /// \param protocol Fetch protocol, either IOFetch::TCP or IOFetch::UDP
+    /// \param service I/O Service object to handle the asynchronous
+    ///     operations.
+    /// \param outpkt Packet to send to upstream server.  Note that the
+    ///     QID (first two bytes of the packet) may be altered in the sending.
+    /// \param buff Output buffer into which the response (in wire format)
+    ///     is written (if a response is received).
+    /// \param cb Callback object containing the callback to be called
+    ///     when we terminate.  The caller is responsible for managing this
+    ///     object and deleting it if necessary.
+    /// \param address IP address of upstream server
+    /// \param port Port to which to connect on the upstream server
+    /// (default = 53)
+    /// \param wait Timeout for the fetch (in ms).  The default value of
+    ///     -1 indicates no timeout.
+    IOFetch(Protocol protocol, isc::asiolink::IOService& service,
+            isc::util::OutputBufferPtr& outpkt,
+            const isc::asiolink::IOAddress& address,
+            uint16_t port, isc::util::OutputBufferPtr& buff, Callback* cb,
+            int wait = -1);
+
+    /// \brief Return Current Protocol
+    ///
+    /// \return Protocol associated with this IOFetch object.
+    Protocol getProtocol() const;
+
+    /// \brief Coroutine entry point
+    ///
+    /// The operator() method is the method in which the coroutine code enters
+    /// this object when an operation has been completed.
+    ///
+    /// \param ec Error code, the result of the last asynchronous I/O operation.
+    /// \param length Amount of data received on the last asynchronous read
+    void operator()(boost::system::error_code ec = boost::system::error_code(), size_t length = 0);
+
+    /// \brief Terminate query
+    ///
+    /// This method can be called at any point.  It terminates the current
+    /// query with the specified reason.
+    ///
+    /// \param reason Reason for terminating the query
+    void stop(Result reason = STOPPED);
+
+private:
+    /// \brief IOFetch Initialization Function.
+    /// All the parameters are same with the constructor, except
+    /// parameter "query_message"
+    /// \param query_message the message to be sent out.
+    void initIOFetch(isc::dns::MessagePtr& query_message, Protocol protocol,
+                     isc::asiolink::IOService& service,
+                     const isc::dns::Question& question,
+                     const isc::asiolink::IOAddress& address, uint16_t port,
+                     isc::util::OutputBufferPtr& buff, Callback* cb, int wait,
+                     bool edns = true);
+
+    /// \brief Log I/O Failure
+    ///
+    /// Records an I/O failure to the log file
+    ///
+    /// \param ec ASIO error code
+    void logIOFailure(boost::system::error_code ec);
+
+    // Member variables.  All data is in a structure pointed to by a shared
+    // pointer.  The IOFetch object is copied a number of times during its
+    // life, and only requiring a pointer to be copied reduces overhead.
+    boost::shared_ptr<IOFetchData> data_;   ///< Private data
+};
+
+/// \brief Defines a pointer to an IOFetch.
+typedef boost::shared_ptr<IOFetch> IOFetchPtr;
+
+} // namespace asiodns
+} // namespace isc
+
+#endif // IO_FETCH_H