Adding upstream version 2.4.1.upstream/2.4.1upstream

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

1 files changed, 161 insertions, 0 deletions

diff --git a/src/bin/perfdhcp/pkt_transform.h b/src/bin/perfdhcp/pkt_transform.h
new file mode 100644
index 0000000..99cdb19
--- /dev/null
+++ b/src/bin/perfdhcp/pkt_transform.h
@@ -0,0 +1,161 @@
+// Copyright (C) 2012-2019 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 PKT_TRANSFORM_H
+#define PKT_TRANSFORM_H
+
+#include <perfdhcp/localized_option.h>
+
+#include <dhcp/option.h>
+
+namespace isc {
+namespace perfdhcp {
+
+/// \brief Read and write raw data to DHCP packets.
+///
+/// This class provides static functions to read/write raw data from/to the
+/// packet buffer. When reading data with the unpack() method, the
+/// corresponding options objects are updated.  When writing to the packet
+/// buffer with pack(), options objects carry input data to be written.
+///
+/// This class is used both by \ref PerfPkt4 and
+/// \ref PerfPkt6 classes in case DHCP packets are created
+/// from template files. In this case, some of the template
+/// packet's options are replaced before sending it to the
+/// server. Offset of specific options are provided from the
+/// command line by the perfdhcp tool user, and passed in an
+/// options collection.
+class PktTransform {
+public:
+
+    /// \brief Prepares on-wire format from raw buffer.
+    ///
+    /// The method copies the input buffer and options contents
+    /// to the output buffer. The input buffer must contain whole
+    /// initial packet data. Parts of this data will be
+    /// overridden by options data specified in an options
+    /// collection. Such options must have their offsets within
+    /// a packet specified (see \ref LocalizedOption to find out
+    /// how to specify options offset).
+    ///
+    /// \note The specified options must fit into the size of the
+    /// initial packet data. A call to this method will fail
+    /// if the option's offset + its size is beyond the packet's size.
+    ///
+    /// \param universe Universe used, V4 or V6
+    /// \param in_buffer Input buffer holding initial packet
+    /// data, this can be directly read from template file
+    /// \param options Options collection with offsets
+    /// \param transid_offset offset of transaction id in a packet,
+    /// transaction ID will be written to output buffer at this
+    /// offset
+    /// \param transid Transaction ID value
+    /// \param out_buffer Output buffer holding "packed" data
+    ///
+    /// \return false, if pack operation failed.
+    static bool pack(const dhcp::Option::Universe universe,
+                     const dhcp::OptionBuffer& in_buffer,
+                     const dhcp::OptionCollection& options,
+                     const size_t transid_offset,
+                     const uint32_t transid,
+                     util::OutputBuffer& out_buffer);
+
+    /// \brief Handles selective binary packet parsing.
+    ///
+    /// This method handles the parsing of packets that have non-default
+    /// options or transaction ID offsets. The client class has to use
+    /// \ref isc::dhcp::Pkt6::addOption to specify which options to parse.
+    /// Each option should be of the \ref isc::perfdhcp::LocalizedOption
+    /// type with the offset value specified.
+    ///
+    /// \param universe universe used, V4 or V6
+    /// \param in_buffer input buffer to be parsed
+    /// \param options options collection with options offsets
+    /// \param transid_offset offset of transaction id in input buffer
+    /// \param transid transaction id value read from input buffer
+    ///
+    /// \return false, if unpack operation failed.
+    static bool unpack(const dhcp::Option::Universe universe,
+                       const dhcp::OptionBuffer& in_buffer,
+                       const dhcp::OptionCollection& options,
+                       const size_t transid_offset,
+                       uint32_t& transid);
+
+    /// \brief Replace contents of buffer with vector.
+    ///
+    /// Function replaces data of the buffer with data from vector.
+    ///
+    /// \param in_buffer destination buffer.
+    /// \param dest_pos position in destination buffer.
+    /// \param first beginning of data range in source vector.
+    /// \param last end of data range in source vector.
+    static void writeAt(dhcp::OptionBuffer& in_buffer, size_t dest_pos,
+                        std::vector<uint8_t>::iterator first,
+                        std::vector<uint8_t>::iterator last);
+
+    /// \brief Replace contents of one vector with uint16 value.
+    ///
+    /// Function replaces data inside one vector with uint16_t value.
+    ///
+    /// \param in_buffer destination buffer.
+    /// \param dest_pos position in destination buffer.
+    /// \param val value to be written.
+    template<typename T>
+    static void writeValueAt(dhcp::OptionBuffer& in_buffer, size_t dest_pos,
+                        T val) {
+        // @todo consider replacing the loop with switch statement
+        // checking sizeof(T).
+        for (int i = 0; i < sizeof(T); ++i) {
+            in_buffer[dest_pos + i] = (val >> 8 * (sizeof(T) - i - 1)) & 0xFF;
+        }
+    }
+
+private:
+    /// \brief Replaces contents of options in a buffer.
+    ///
+    /// The method uses a localized options collection to
+    /// replace parts of packet data (e.g. data read
+    /// from template file).
+    /// This private method is called from \ref PktTransform::pack
+    ///
+    /// \param in_buffer input buffer holding initial packet data.
+    /// \param out_buffer output buffer with "packed" options.
+    /// \param options options collection with actual data and offsets.
+    ///
+    /// \throw isc::Unexpected if options update failed.
+    static void packOptions(const dhcp::OptionBuffer& in_buffer,
+                            const dhcp::OptionCollection& options,
+                            util::OutputBuffer& out_buffer);
+
+    /// \brief Reads contents of specified options from buffer.
+    ///
+    /// The method reads options data from the input buffer
+    /// and stores it in options objects. Offsets of the options
+    /// must be specified (see \ref LocalizedOption to find out how to specify
+    /// the option offset).
+    /// This private method is called by \ref PktTransform::unpack.
+    ///
+    /// \note This method iterates through all options in an
+    /// options collection, checks the offset of the option
+    /// in input buffer and reads data from the buffer to
+    /// update the option's buffer. If the provided options collection
+    /// is empty, a call to this method will have no effect.
+    ///
+    /// \param universe universe used, V4 or V6
+    /// \param in_buffer input buffer to be parsed.
+    /// \param options options collection with their offsets
+    /// in input buffer specified.
+    ///
+    /// \throw isc::Unexpected if options unpack failed.
+    static void unpackOptions(const dhcp::OptionBuffer& in_buffer,
+                              const dhcp::OptionCollection& options);
+
+};
+
+} // namespace perfdhcp
+} // namespace isc
+
+#endif // PKT_TRANSFORM_H