Packet trailer for Ethernet. More...
#include "ethernet-trailer.h"
Public Member Functions | |
EthernetTrailer () | |
Construct a null ethernet trailer. More... | |
void | CalcFcs (Ptr< const Packet > p) |
Updates the Fcs Field to the correct FCS. More... | |
bool | CheckFcs (Ptr< const Packet > p) const |
Calculate an FCS on the provided packet and check this value against the FCS found when the trailer was deserialized (the one in the transmitted packet). More... | |
uint32_t | Deserialize (Buffer::Iterator end) override |
void | EnableFcs (bool enable) |
Enable or disable FCS checking and calculations. More... | |
uint32_t | GetFcs () const |
TypeId | GetInstanceTypeId () const override |
Get the most derived TypeId for this Object. More... | |
uint32_t | GetSerializedSize () const override |
uint32_t | GetTrailerSize () const |
void | Print (std::ostream &os) const override |
void | Serialize (Buffer::Iterator end) const override |
void | SetFcs (uint32_t fcs) |
Sets the FCS to a new value. More... | |
Public Member Functions inherited from ns3::Trailer | |
~Trailer () override | |
uint32_t | Deserialize (Buffer::Iterator start, Buffer::Iterator end) override |
Public Member Functions inherited from ns3::ObjectBase | |
virtual | ~ObjectBase () |
Virtual destructor. More... | |
void | GetAttribute (std::string name, AttributeValue &value) const |
Get the value of an attribute, raising fatal errors if unsuccessful. More... | |
bool | GetAttributeFailSafe (std::string name, AttributeValue &value) const |
Get the value of an attribute without raising errors. More... | |
void | SetAttribute (std::string name, const AttributeValue &value) |
Set a single attribute, raising fatal errors if unsuccessful. More... | |
bool | SetAttributeFailSafe (std::string name, const AttributeValue &value) |
Set a single attribute without raising errors. More... | |
bool | TraceConnect (std::string name, std::string context, const CallbackBase &cb) |
Connect a TraceSource to a Callback with a context. More... | |
bool | TraceConnectWithoutContext (std::string name, const CallbackBase &cb) |
Connect a TraceSource to a Callback without a context. More... | |
bool | TraceDisconnect (std::string name, std::string context, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected with a context. More... | |
bool | TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb) |
Disconnect from a TraceSource a Callback previously connected without a context. More... | |
Static Public Member Functions | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Static Public Member Functions inherited from ns3::Trailer | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Static Public Member Functions inherited from ns3::Chunk | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Static Public Member Functions inherited from ns3::ObjectBase | |
static TypeId | GetTypeId () |
Get the type ID. More... | |
Private Attributes | |
bool | m_calcFcs |
Enabled FCS calculations. More... | |
uint32_t | m_fcs |
Value of the fcs contained in the trailer. More... | |
Additional Inherited Members | |
Protected Member Functions inherited from ns3::ObjectBase | |
void | ConstructSelf (const AttributeConstructionList &attributes) |
Complete construction of ObjectBase; invoked by derived classes. More... | |
virtual void | NotifyConstructionCompleted () |
Notifier called once the ObjectBase is fully constructed. More... | |
Related Functions inherited from ns3::ObjectBase | |
static TypeId | GetObjectIid () |
Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly. More... | |
Packet trailer for Ethernet.
This class can be used to add and verify the FCS at the end of an Ethernet packet.
Definition at line 39 of file ethernet-trailer.h.
ns3::EthernetTrailer::EthernetTrailer | ( | ) |
Construct a null ethernet trailer.
Definition at line 35 of file ethernet-trailer.cc.
References NS_LOG_FUNCTION.
Updates the Fcs Field to the correct FCS.
p | Reference to a packet on which the FCS should be calculated. The packet should not currently contain an EthernetTrailer. |
Definition at line 70 of file ethernet-trailer.cc.
References ns3::Packet::CopyData(), ns3::CRC32Calculate(), ns3::Packet::GetSize(), m_calcFcs, m_fcs, and NS_LOG_FUNCTION.
Referenced by ns3::CsmaNetDevice::AddHeader().
Calculate an FCS on the provided packet and check this value against the FCS found when the trailer was deserialized (the one in the transmitted packet).
If FCS checking is disabled, this method will always return true.
p | Reference to the packet on which the FCS should be calculated. The packet should not contain an EthernetTrailer. |
Definition at line 50 of file ethernet-trailer.cc.
References ns3::Packet::CopyData(), ns3::CRC32Calculate(), ns3::Packet::GetSize(), m_calcFcs, m_fcs, and NS_LOG_FUNCTION.
Referenced by ns3::CsmaNetDevice::Receive().
|
overridevirtual |
end | an iterator which points to the end of the buffer where the trailer should be read from. |
This method is used by Packet::RemoveTrailer to re-create a trailer from the byte buffer of a packet. The data read is expected to match bit-for-bit the representation of this trailer in real networks. The input iterator points to the end of the area where the data shall be read from. This method is thus expected to call Buffer::Iterator::Prev prior to actually reading any data.
Implements ns3::Trailer.
Definition at line 149 of file ethernet-trailer.cc.
References GetSerializedSize(), m_fcs, NS_LOG_FUNCTION, ns3::Buffer::Iterator::Prev(), and ns3::Buffer::Iterator::ReadU32().
void ns3::EthernetTrailer::EnableFcs | ( | bool | enable | ) |
Enable or disable FCS checking and calculations.
enable | If true, enables FCS calculations. |
Definition at line 43 of file ethernet-trailer.cc.
References m_calcFcs, and NS_LOG_FUNCTION.
Referenced by ns3::CsmaNetDevice::AddHeader(), and ns3::CsmaNetDevice::Receive().
uint32_t ns3::EthernetTrailer::GetFcs | ( | ) | const |
Definition at line 95 of file ethernet-trailer.cc.
References m_fcs, and NS_LOG_FUNCTION.
|
overridevirtual |
Get the most derived TypeId for this Object.
This method is typically implemented by ns3::Object::GetInstanceTypeId but some classes which derive from ns3::ObjectBase directly have to implement it themselves.
Implements ns3::ObjectBase.
Definition at line 119 of file ethernet-trailer.cc.
References GetTypeId().
|
overridevirtual |
This method is used by Packet::AddTrailer to store a trailer into the byte buffer of a packet. This method should return the number of bytes which are needed to store the full trailer data by Serialize.
Implements ns3::Trailer.
Definition at line 132 of file ethernet-trailer.cc.
References NS_LOG_FUNCTION.
Referenced by Deserialize(), GetTrailerSize(), and Serialize().
uint32_t ns3::EthernetTrailer::GetTrailerSize | ( | ) | const |
Definition at line 102 of file ethernet-trailer.cc.
References GetSerializedSize(), and NS_LOG_FUNCTION.
|
static |
Get the type ID.
Definition at line 109 of file ethernet-trailer.cc.
References ns3::TypeId::SetParent().
Referenced by GetInstanceTypeId().
|
overridevirtual |
os | output stream This method is used by Packet::Print to print the content of a trailer as ascii data to a c++ output stream. Although the trailer is free to format its output as it wishes, it is recommended to follow a few rules to integrate with the packet pretty printer: start with flags, small field values located between a pair of parens. Values should be separated by whitespace. Follow the parens with the important fields, separated by whitespace. i.e.: (field1 val1 field2 val2 field3 val3) field4 val4 field5 val5 |
Implements ns3::Trailer.
Definition at line 125 of file ethernet-trailer.cc.
References m_fcs, and NS_LOG_FUNCTION.
|
overridevirtual |
start | an iterator which points to where the trailer should be written. |
This method is used by Packet::AddTrailer to store a header into the byte buffer of a packet. The data written is expected to match bit-for-bit the representation of this trailer in real networks. The input iterator points to the end of the area where the data shall be written. This method is thus expected to call Buffer::Iterator::Prev prior to actually writing any data.
Implements ns3::Trailer.
Definition at line 139 of file ethernet-trailer.cc.
References GetSerializedSize(), m_fcs, NS_LOG_FUNCTION, ns3::Buffer::Iterator::Prev(), and ns3::Buffer::Iterator::WriteU32().
void ns3::EthernetTrailer::SetFcs | ( | uint32_t | fcs | ) |
Sets the FCS to a new value.
fcs | New FCS value |
Definition at line 88 of file ethernet-trailer.cc.
References m_fcs, and NS_LOG_FUNCTION.
|
private |
Enabled FCS calculations.
If false, m_fcs is set to 0 and CheckFcs returns true.
Definition at line 109 of file ethernet-trailer.h.
Referenced by CalcFcs(), CheckFcs(), and EnableFcs().
|
private |
Value of the fcs contained in the trailer.
Definition at line 110 of file ethernet-trailer.h.
Referenced by CalcFcs(), CheckFcs(), Deserialize(), GetFcs(), Print(), Serialize(), and SetFcs().