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Svc::AuthenticationRouter

The Svc::AuthenticationRouter component routes F´ packets (such as command or file packets) to other components. It is based on the FPrime Router, explained and linked later in the sdd, with two exceptions

  1. Command Loss Time component, which checks how long since commands have last been routed through the satellite. If it has been too long (changeable parameter) it will emit an event and send out to safemode, to conserve power As a result of this component writing to the filesystem, this component is active, while the usual FprimeRouter is passive.

  2. This component handles authenticated packets. It will check a list of preconfigured opcodes that do not need to be authenticated, will pass those on as well as the things that are authenticated

The Svc::AuthenticationRouter component receives F´ packets (as Fw::Buffer objects) and routes them to other components through synchronous port calls. The input port of type Svc.ComDataWithContext passes this Fw.Buffer object along with optional context data which can help for routing. The current F Prime protocol does not use this context data, but is nevertheless present in the interface for compatibility with other protocols which may for example pass APIDs in the frame headers.

The Svc::AuthenticationRouter component supports Fw::ComPacketType::FW_PACKET_COMMAND and Fw::ComPacketType::FW_PACKET_FILE packet types. Unknown packet types are forwarded on the unknownDataOut port, which a project-specific component can connect to for custom routing.

About memory management, all buffers sent by Svc::AuthenticationRouter on the fileOut and unknownDataOut ports are expected to be returned to the router through the fileBufferReturnIn port for deallocation.

Custom Routing

The Svc::AuthenticationRouter component is designed to be extensible through the use of a project-specific router. The unknownDataOut port can be connected to a project-specific component that can receive all unknown packet types. This component can then implement custom handling of these unknown packets. After processing, the project-specific component shall return the received buffer to the Svc::AuthenticationRouter component through the fileBufferReturnIn port (named this way as it only receives file packets in the common use-case), which will deallocate the buffer.

Usage Examples

The Svc::FprimeRouter component is used in the uplink stack of many reference F´ application such as the tutorials source code.

Typical Usage

In the canonical uplink communications stack, Svc::FprimeRouter is connected to Svc::CmdDispatcher and Svc::FileUplink components, to receive Command and File packets respectively. See the F Prime documentation for more details on these components.

Port Descriptions

Kind Name Type Description
async input schedIn Svc.Sched Port receiving calls from the rate group for periodic command loss time checking
async input dataIn Svc.ComDataWithContext Receiving Fw::Buffer with context buffer from Deframer
output dataReturnOut Svc.ComDataWithContext Returning ownership of buffer received on dataIn
output commandOut Fw.Com Port for sending command packets as Fw::ComBuffers
output fileOut Fw.BufferSend Port for sending file packets as Fw::Buffer (ownership passed to receiver)
sync input fileBufferReturnIn Fw.BufferSend Receiving back ownership of buffer sent on fileOut and unknownDataOut
sync input cmdResponseIn Fw.CmdResponse Port for receiving command responses from a command dispatcher (can be a no-op)
output unknownDataOut Svc.ComDataWithContext Port forwarding unknown data (useful for adding custom routing rules with a project-defined router)
output bufferAllocate Fw.BufferGet Port for allocating buffers, allowing copy of received data
output bufferDeallocate Fw.BufferSend Port for deallocating buffers
output SafeModeOn Fw.Signal Port for sending signal to safemode when command loss time expires

Requirements

Name Description Rationale Validation
SVC-ROUTER-001 Svc::AuthenticationRouter shall route packets based on their packet type as indicated by the packet header Routing mechanism of the F´ comms protocol Unit test
SVC-ROUTER-002 Svc::AuthenticationRouter shall route packets of type Fw::ComPacketType::FW_PACKET_COMMAND to the commandOut output port. Routing command packets Unit test
SVC-ROUTER-003 Svc::AuthenticationRouter shall route packets of type Fw::ComPacketType::FW_PACKET_FILE to the fileOut output port. Routing file packets Unit test
SVC-ROUTER-004 Svc::AuthenticationRouter shall route data that is neither Fw::ComPacketType::FW_PACKET_COMMAND nor Fw::ComPacketType::FW_PACKET_FILE to the unknownDataOut output port. Allows for projects to provide custom routing for additional (project-specific) uplink data types Unit test
SVC-ROUTER-005 Svc::AuthenticationRouter shall emit warning events if serialization errors occur during processing of incoming packets Aid in diagnosing uplink issues Unit test
SVC-ROUTER-005 Svc::AuthenticationRouter shall make a copy of buffers that represent a FW_PACKET_FILE Aid in memory management of file buffers Unit test
SVC-ROUTER-006 Svc::AuthenticationRouter shall return ownership of all buffers received on dataIn through dataReturnOut Memory management Unit test
SVC-ROUTER-007 Svc::AuthenticationRouter shall check command loss time periodically via the schedIn port Command loss time monitoring Unit test
SVC-ROUTER-008 Svc::AuthenticationRouter shall emit CommandLossTimeExpired event when command loss time exceeds LOSS_MAX_TIME parameter Command loss time monitoring Unit test
SVC-ROUTER-009 Svc::AuthenticationRouter shall send SafeModeOn signal when command loss time expires Safe mode activation Unit test
SVC-ROUTER-010 Svc::AuthenticationRouter shall update LastCommandPacketTime telemetry when a packet is received Telemetry tracking Unit test
SVC-ROUTER-011 Svc::AuthenticationRouter shall use the 0/1 setting in authenticateCfg.hpp to enable or disable authentication functionality in this router component Authentication configuration Unit test
SVC-ROUTER-012 Svc::AuthenticationRouter shall check a file for OpCodes that do not require authentication OpCode exemption list Unit test
SVC-ROUTER-013 Svc::AuthenticationRouter shall only pass authenticated commands and files that are not on the list of opcodes to be executed Authentication filtering Unit test
SVC-ROUTER-014 Svc::AuthenticationRouter shall pass non-authenticated commands and events backwards to dataOut Non-authenticated packet routing Unit test
SVC-ROUTER-015 Svc::AuthenticationRouter shall emit events for authenticated commands and non-authenticated commands and whether they passed through the router Authentication event reporting Unit test

Events

Name Severity Parameters Description
CommandLossTimeExpired Activity High safemode: Fw.On Emitted when command loss time expires. Format: "SafeModeOn: {}"
CurrentLossTime Activity Low loss_max_time: U32 Emitted with current loss time information. Format: "Current Loss Time: {}"
PassedRouter Activity Low passed: Fw.Bool Emitted to indicate whether a packet passed through the router. Format: "PassedRouter: {}"
BypassAuthentification Activity Low bypassed: Fw.Bool Emitted to indicate whether authentication was bypassed. Format: "BypassAuthentification: {}"

Telemetry Channels

Name Type Description
LastCommandPacketTime U64 The time of the last command packet
CommandLossSafeOn bool The status of the command loss time sending to safe mode
ByPassedRouter U64 Number of Packets that have bypassed the router
PassedRouter U64 Number of Packets that have passed the router
FailedRouter U64 Number of Packets that have not passed the Router

Parameters

Name Type Default Description
LOSS_MAX_TIME U32 10 The maximum amount of time (in seconds) since the last command before triggering safe mode