From 22d213c4846d2d783a8e84cc0b8e067dfe9b1a1e Mon Sep 17 00:00:00 2001 From: Vijay Kumar Banerjee Date: Mon, 1 Mar 2021 09:44:55 -0700 Subject: networking: Rename to legacy networking --- legacy-networking/command.rst | 9 + legacy-networking/conf.py | 14 + legacy-networking/dec_21140.rst | 236 +++++++ legacy-networking/index.rst | 31 + legacy-networking/network_servers.rst | 116 +++ legacy-networking/network_task_structure.rst | 33 + legacy-networking/networking_driver.rst | 305 ++++++++ legacy-networking/preface.rst | 38 + legacy-networking/testing_the_driver.rst | 299 ++++++++ legacy-networking/using_networking_rtems_app.rst | 851 +++++++++++++++++++++++ legacy-networking/wscript | 7 + 11 files changed, 1939 insertions(+) create mode 100644 legacy-networking/command.rst create mode 100644 legacy-networking/conf.py create mode 100644 legacy-networking/dec_21140.rst create mode 100644 legacy-networking/index.rst create mode 100644 legacy-networking/network_servers.rst create mode 100644 legacy-networking/network_task_structure.rst create mode 100644 legacy-networking/networking_driver.rst create mode 100644 legacy-networking/preface.rst create mode 100644 legacy-networking/testing_the_driver.rst create mode 100644 legacy-networking/using_networking_rtems_app.rst create mode 100644 legacy-networking/wscript (limited to 'legacy-networking') diff --git a/legacy-networking/command.rst b/legacy-networking/command.rst new file mode 100644 index 0000000..269d50d --- /dev/null +++ b/legacy-networking/command.rst @@ -0,0 +1,9 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +Command and Variable Index +########################## + +There are currently no Command and Variable Index entries. + +.. COMMENT: @printindex fn + diff --git a/legacy-networking/conf.py b/legacy-networking/conf.py new file mode 100644 index 0000000..98a06b6 --- /dev/null +++ b/legacy-networking/conf.py @@ -0,0 +1,14 @@ +import sys, os +sys.path.insert(0, os.path.abspath('../common/')) + +from conf import * + +project = "RTEMS Legacy Networking User Manual" + +latex_documents = [ + ('index', + 'legacy-networking.tex', + u'RTEMS Legacy Networking User Manual', + u'RTEMS Documentation Project', + 'manual'), +] diff --git a/legacy-networking/dec_21140.rst b/legacy-networking/dec_21140.rst new file mode 100644 index 0000000..5463b7d --- /dev/null +++ b/legacy-networking/dec_21140.rst @@ -0,0 +1,236 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +DEC 21140 Driver +################ + +DEC 21240 Driver Introduction +============================= + +.. COMMENT: XXX add back in cross reference to list of boards. + +One aim of our project is to port RTEMS on a standard PowerPC platform. To +achieve it, we have chosen a Motorola MCP750 board. This board includes an +Ethernet controller based on a DEC21140 chip. Because RTEMS has a TCP/IP stack, +we will have to develop the DEC21140 related ethernet driver for the PowerPC +port of RTEMS. As this controller is able to support 100Mbps network and as +there is a lot of PCI card using this DEC chip, we have decided to first +implement this driver on an Intel PC386 target to provide a solution for using +RTEMS on PC with the 100Mbps network and then to port this code on PowerPC in a +second phase. + +The aim of this document is to give some PCI board generalities and to explain +the software architecture of the RTEMS driver. Finally, we will see what will +be done for ChorusOs and Netboot environment . + +Document Revision History +========================= + +*Current release*: + +- Current applicable release is 1.0. + +*Existing releases*: + +- 1.0 : Released the 10/02/98. First version of this document. + +- 0.1 : First draft of this document + +*Planned releases*: + +- None planned today. + +DEC21140 PCI Board Generalities +=============================== + +.. COMMENT: XXX add crossreference to PCI Register Figure + +This chapter describes rapidely the PCI interface of this Ethernet controller. +The board we have chosen for our PC386 implementation is a D-Link DFE-500TX. +This is a dual-speed 10/100Mbps Ethernet PCI adapter with a DEC21140AF chip. +Like other PCI devices, this board has a PCI device's header containing some +required configuration registers, as shown in the PCI Register Figure. By +reading or writing these registers, a driver can obtain information about the +type of the board, the interrupt it uses, the mapping of the chip specific +registers, ... + +On Intel target, the chip specific registers can be accessed via 2 methods : +I/O port access or PCI address mapped access. We have chosen to implement the +PCI address access to obtain compatible source code to the port the driver on a +PowerPC target. + +.. COMMENT: PCI Device's Configuration Header Space Format + + +.. figure ../images/networking/PCIreg.png + :align: center + :alt: PCI Device's Configuration Header Space Format + +.. COMMENT: XXX add crossreference to PCI Register Figure + +On RTEMS, a PCI API exists. We have used it to configure the board. After +initializing this PCI module via the ``pci_initialize()`` function, we try to +detect the DEC21140 based ethernet board. This board is characterized by its +Vendor ID (0x1011) and its Device ID (0x0009). We give these arguments to +the``pcib_find_by_deviceid`` function which returns , if the device is present, +a pointer to the configuration header space (see PCI Registers Fgure). Once +this operation performed, the driver is able to extract the information it +needs to configure the board internal registers, like the interrupt line, the +base address,... The board internal registers will not be detailled here. You +can find them in *DIGITAL Semiconductor 21140A PCI Fast Ethernet LAN Controller +- Hardware Reference Manual*. + +.. COMMENT: fix citation + +RTEMS Driver Software Architecture +================================== + +In this chapter will see the initialization phase, how the controller uses the +host memory and the 2 threads launched at the initialization time. + +Initialization phase +-------------------- + +The DEC21140 Ethernet driver keeps the same software architecture than the +other RTEMS ethernet drivers. The only API the programmer can use is the +``rtems_dec21140_driver_attach(struct rtems_bsdnet_ifconfig *config)`` +function which detects the board and initializes the associated data structure +(with registers base address, entry points to low-level initialization +function,...), if the board is found. + +Once the attach function executed, the driver initializes the DEC chip. Then +the driver connects an interrupt handler to the interrupt line driven by the +Ethernet controller (the only interrupt which will be treated is the receive +interrupt) and launches 2 threads : a receiver thread and a transmitter +thread. Then the driver waits for incoming frame to give to the protocol stack +or outcoming frame to send on the physical link. + +Memory Buffer +------------- + +.. COMMENT: XXX add cross reference to Problem + +This DEC chip uses the host memory to store the incoming Ethernet frames and +the descriptor of these frames. We have chosen to use 7 receive buffers and 1 +transmit buffer to optimize memory allocation due to cache and paging problem +that will be explained in the section *Encountered Problems*. + +To reference these buffers to the DEC chip we use a buffer descriptors +ring. The descriptor structure is defined in the Buffer Descriptor Figure. +Each descriptor can reference one or two memory buffers. We choose to use only +one buffer of 1520 bytes per descriptor. + +The difference between a receive and a transmit buffer descriptor is located in +the status and control bits fields. We do not give details here, please refer +to the DEC21140 Hardware Manual. + +.. COMMENT: Buffer Descriptor + + +.. figure:: ../images/networking/recvbd.png + :align: center + :alt: Buffer Descriptor + +Receiver Thread +--------------- + +This thread is event driven. Each time a DEC PCI board interrupt occurs, the +handler checks if this is a receive interrupt and send an event "reception" to +the receiver thread which looks into the entire buffer descriptors ring the +ones that contain a valid incoming frame (bit OWN=0 means descriptor belongs to +host processor). Each valid incoming ethernet frame is sent to the protocol +stack and the buffer descriptor is given back to the DEC board (the host +processor reset bit OWN, which means descriptor belongs to 21140). + +Transmitter Thread +------------------ + +This thread is also event driven. Each time an Ethernet frame is put in the +transmit queue, an event is sent to the transmit thread, which empty the queue +by sending each outcoming frame. Because we use only one transmit buffer, we +are sure that the frame is well-sent before sending the next. + +Encountered Problems +==================== + +On Intel PC386 target, we were faced with a problem of memory cache management. +Because the DEC chip uses the host memory to store the incoming frame and +because the DEC21140 configuration registers are mapped into the PCI address +space, we must ensure that the data read (or written) by the host processor are +the ones written (or read) by the DEC21140 device in the host memory and not +old data stored in the cache memory. Therefore, we had to provide a way to +manage the cache. This module is described in the document *RTEMS Cache +Management For Intel*. On Intel, the memory region cache management is +available only if the paging unit is enabled. We have used this paging +mechanism, with 4Kb page. All the buffers allocated to store the incoming or +outcoming frames, buffer descriptor and also the PCI address space of the DEC +board are located in a memory space with cache disable. + +Concerning the buffers and their descriptors, we have tried to optimize the +memory space in term of allocated page. One buffer has 1520 bytes, one +descriptor has 16 bytes. We have 7 receive buffers and 1 transmit buffer, and +for each, 1 descriptor : (7+1)*(1520+16) = 12288 bytes = 12Kb = 3 entire +pages. This allows not to lose too much memory or not to disable cache memory +for a page which contains other data than buffer, which could decrease +performance. + +Netboot DEC driver +================== + +We use Netboot tool to load our development from a server to the target via an +ethernet network. Currently, this tool does not support the DEC board. We plan +to port the DEC driver for the Netboot tool. + +But concerning the port of the DEC driver into Netboot, we are faced with a +problem: in RTEMS environment, the DEC driver is interrupt or event driven, in +Netboot environment, it must be used in polling mode. It means that we will +have to re-write some mechanisms of this driver. + +List of Ethernet cards using the DEC chip +========================================= + +Many Ethernet adapter cards use the Tulip chip. Here is a non exhaustive list +of adapters which support this driver : + +- Accton EtherDuo PCI. + +- Accton EN1207 All three media types supported. + +- Adaptec ANA6911/TX 21140-AC. + +- Cogent EM110 21140-A with DP83840 N-Way MII transceiver. + +- Cogent EM400 EM100 with 4 21140 100mbps-only ports + PCI Bridge. + +- Danpex EN-9400P3. + +- D-Link DFE500-Tx 21140-A with DP83840 transceiver. + +- Kingston EtherX KNE100TX 21140AE. + +- Netgear FX310 TX 10/100 21140AE. + +- SMC EtherPower10/100 With DEC21140 and 68836 SYM transceiver. + +- SMC EtherPower10/100 With DEC21140-AC and DP83840 MII transceiver. + Note: The EtherPower II uses the EPIC chip, which requires a different driver. + +- Surecom EP-320X DEC 21140. + +- Thomas Conrad TC5048. + +- Znyx ZX345 21140-A, usually with the DP83840 N-Way MII transciever. Some ZX345 + cards made in 1996 have an ICS 1890 transciver instead. + +- ZNYX ZX348 Two 21140-A chips using ICS 1890 transcievers and either a 21052 + or 21152 bridge. Early versions used National 83840 transcievers, but later + versions are depopulated ZX346 boards. + +- ZNYX ZX351 21140 chip with a Broadcom 100BaseT4 transciever. + +Our DEC driver has not been tested with all these cards, only with the D-Link +DFE500-TX. + +- DEC21140 Hardware Manual DIGITAL, DIGITAL Semiconductor 21140A PCI Fast + Ethernet LAN Controller - Hardware Reference Manual**. + +- *[99.TA.0021.M.ER]Emmanuel Raguet,*RTEMS Cache Management For Intel**. diff --git a/legacy-networking/index.rst b/legacy-networking/index.rst new file mode 100644 index 0000000..b85119d --- /dev/null +++ b/legacy-networking/index.rst @@ -0,0 +1,31 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. include:: ../common/unicode.rst + +.. highlight:: c + +====================================== +RTEMS Legacy Network User Manual (|version|). +====================================== + +.. topic:: Copyrights and License + + | |copy| 2018 Marçal Comajoan Cara + | |copy| 1988, 2015 On-Line Applications Research Corporation (OAR) + + .. include:: ../common/license.rst + +.. include:: ../common/header.rst + +.. toctree:: + :maxdepth: 3 + :numbered: + + preface + network_task_structure + networking_driver + using_networking_rtems_app + testing_the_driver + network_servers + dec_21140 + command diff --git a/legacy-networking/network_servers.rst b/legacy-networking/network_servers.rst new file mode 100644 index 0000000..941a6e2 --- /dev/null +++ b/legacy-networking/network_servers.rst @@ -0,0 +1,116 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. COMMENT: RTEMS Remote Debugger Server Specifications +.. COMMENT: Written by: Emmanuel Raguet + +Network Servers +############### + +RTEMS FTP Daemon +================ + +The RTEMS FTPD is a complete file transfer protocol (FTP) daemon which can +store, retrieve, and manipulate files on the local filesystem. In addition, +the RTEMS FTPD provides "hooks" which are actions performed on received data. +Hooks are useful in situations where a destination file is not necessarily +appropriate or in cases when a formal device driver has not yet been +implemented. + +This server was implemented and documented by Jake Janovetz +(janovetz@tempest.ece.uiuc.edu). + +Configuration Parameters +------------------------ + +The configuration structure for FTPD is as follows: + +.. code-block:: c + + struct rtems_ftpd_configuration + { + rtems_task_priority priority; /* FTPD task priority */ + unsigned long max_hook_filesize; /* Maximum buffersize */ + /* for hooks */ + int port; /* Well-known port */ + struct rtems_ftpd_hook *hooks; /* List of hooks */ + }; + +The FTPD task priority is specified with ``priority``. Because hooks are not +saved as files, the received data is placed in an allocated buffer. +``max_hook_filesize`` specifies the maximum size of this buffer. Finally, +``hooks`` is a pointer to the configured hooks structure. + +Initializing FTPD (Starting the daemon) +--------------------------------------- + +Starting FTPD is done with a call to ``rtems_initialize_ftpd()``. The +configuration structure must be provided in the application source code. +Example hooks structure and configuration structure folllow. + +.. code-block:: c + + struct rtems_ftpd_hook ftp_hooks[] = + { + {"untar", Untar_FromMemory}, + {NULL, NULL} + }; + + struct rtems_ftpd_configuration rtems_ftpd_configuration = + { + 40, /* FTPD task priority */ + 512*1024, /* Maximum hook 'file' size */ + 0, /* Use default port */ + ftp_hooks, /* Local ftp hooks */ + 0, /* Use / as root */ + 1, /* Max. connections */ + 0, /* Infinite idle timeout */ + 0, /* Read-write access */ + 0, /* Ignore login check */ + true /* Say hello */ + }; + +Specifying 0 for the well-known port causes FTPD to use the UNIX standard FTPD +port (21). + +Using Hooks +----------- + +In the example above, one hook was installed. The hook causes FTPD to call the +function ``Untar_FromMemory`` when the user sends data to the file ``untar``. +The prototype for the ``untar`` hook (and hooks, in general) is: + +.. code-block:: c + + int Untar_FromMemory(void *tar_buf, size_t size); + +An example FTP transcript which exercises this hook is: + +.. code-block:: shell + + 220 RTEMS FTP server (Version 1.0-JWJ) ready. + Name (dcomm0:janovetz): John Galt + 230 User logged in. + Remote system type is RTEMS. + ftp> bin + 200 Type set to I. + ftp> dir + 200 PORT command successful. + 150 ASCII data connection for LIST. + drwxrwx--x 0 0 268 dev + drwxrwx--x 0 0 0 TFTP + 226 Transfer complete. + ftp> put html.tar untar + local: html.tar remote: untar + 200 PORT command successful. + 150 BINARY data connection. + 210 File transferred successfully. + 471040 bytes sent in 0.48 secs (9.6e+02 Kbytes/sec) + ftp> dir + 200 PORT command successful. + 150 ASCII data connection for LIST. + drwxrwx--x 0 0 268 dev + drwxrwx--x 0 0 0 TFTP + drwxrwx--x 0 0 3484 public_html + 226 Transfer complete. + ftp> quit + 221 Goodbye. diff --git a/legacy-networking/network_task_structure.rst b/legacy-networking/network_task_structure.rst new file mode 100644 index 0000000..2ac031b --- /dev/null +++ b/legacy-networking/network_task_structure.rst @@ -0,0 +1,33 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. COMMENT: Written by Eric Norum +.. Copyright (C) 1988, 2002 On-Line Applications Research Corporation (OAR) + +Network Task Structure and Data Flow +#################################### + +A schematic diagram of the tasks and message *mbuf* queues in a simple RTEMS +networking application is shown in the following figure: + +.. figure:: ../images/networking/networkflow.png + :align: center + :alt: Network Flow + +The transmit task for each network interface is normally blocked waiting for a +packet to arrive in the transmit queue. Once a packet arrives, the transmit +task may block waiting for an event from the transmit interrupt handler. The +transmit interrupt handler sends an RTEMS event to the transmit task to +indicate that transmit hardware resources have become available. + +The receive task for each network interface is normally blocked waiting for an +event from the receive interrupt handler. When this event is received the +receive task reads the packet and forwards it to the network stack for +subsequent processing by the network task. + +The network task processes incoming packets and takes care of timed operations +such as handling TCP timeouts and aging and removing routing table entries. + +The 'Network code' contains routines which may run in the context of the user +application tasks, the interface receive task or the network task. A network +semaphore ensures that the data structures manipulated by the network code +remain consistent. diff --git a/legacy-networking/networking_driver.rst b/legacy-networking/networking_driver.rst new file mode 100644 index 0000000..c161c2b --- /dev/null +++ b/legacy-networking/networking_driver.rst @@ -0,0 +1,305 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. COMMENT: Written by Eric Norum +.. Copyright (C) 1988, 2002 On-Line Applications Research Corporation (OAR) + +Networking Driver +################# + +Introduction +============ + +This chapter is intended to provide an introduction to the procedure for +writing RTEMS network device drivers. The example code is taken from the +'Generic 68360' network device driver. The source code for this driver is +located in the :file:`bsps/m68k/gen68360/net` directory in the +RTEMS source code distribution. Having a copy of this driver at hand when +reading the following notes will help significantly. + +Learn about the network device +============================== + +Before starting to write the network driver become completely familiar with the +programmer's view of the device. The following points list some of the details +of the device that must be understood before a driver can be written. + +- Does the device use DMA to transfer packets to and from memory or does the + processor have to copy packets to and from memory on the device? + +- If the device uses DMA, is it capable of forming a single outgoing packet + from multiple fragments scattered in separate memory buffers? + +- If the device uses DMA, is it capable of chaining multiple outgoing packets, + or does each outgoing packet require intervention by the driver? + +- Does the device automatically pad short frames to the minimum 64 bytes or + does the driver have to supply the padding? + +- Does the device automatically retry a transmission on detection of a + collision? + +- If the device uses DMA, is it capable of buffering multiple packets to + memory, or does the receiver have to be restarted after the arrival of each + packet? + +- How are packets that are too short, too long, or received with CRC errors + handled? Does the device automatically continue reception or does the driver + have to intervene? + +- How is the device Ethernet address set? How is the device programmed to + accept or reject broadcast and multicast packets? + +- What interrupts does the device generate? Does it generate an interrupt for + each incoming packet, or only for packets received without error? Does it + generate an interrupt for each packet transmitted, or only when the transmit + queue is empty? What happens when a transmit error is detected? + +In addition, some controllers have specific questions regarding board specific +configuration. For example, the SONIC Ethernet controller has a very +configurable data bus interface. It can even be configured for sixteen and +thirty-two bit data buses. This type of information should be obtained from +the board vendor. + +Understand the network scheduling conventions +============================================= + +When writing code for the driver transmit and receive tasks, take care to +follow the network scheduling conventions. All tasks which are associated with +networking share various data structures and resources. To ensure the +consistency of these structures the tasks execute only when they hold the +network semaphore (``rtems_bsdnet_semaphore``). The transmit and receive tasks +must abide by this protocol. Be very careful to avoid 'deadly embraces' with +the other network tasks. A number of routines are provided to make it easier +for the network driver code to conform to the network task scheduling +conventions. + +- ``void rtems_bsdnet_semaphore_release(void)`` + This function releases the network semaphore. The network driver tasks must + call this function immediately before making any blocking RTEMS request. + +- ``void rtems_bsdnet_semaphore_obtain(void)`` + This function obtains the network semaphore. If a network driver task has + released the network semaphore to allow other network-related tasks to run + while the task blocks, then this function must be called to reobtain the + semaphore immediately after the return from the blocking RTEMS request. + +- ``rtems_bsdnet_event_receive(rtems_event_set, rtems_option, rtems_interval, rtems_event_set *)`` + The network driver task should call this function when it wishes to wait for + an event. This function releases the network semaphore, calls + ``rtems_event_receive`` to wait for the specified event or events and + reobtains the semaphore. The value returned is the value returned by the + ``rtems_event_receive``. + +Network Driver Makefile +======================= + +Network drivers are considered part of the BSD network package and as such are +to be compiled with the appropriate flags. This can be accomplished by adding +``-D__INSIDE_RTEMS_BSD_TCPIP_STACK__`` to the ``command line``. If the driver +is inside the RTEMS source tree or is built using the RTEMS application +Makefiles, then adding the following line accomplishes this: + +.. code-block:: makefile + + DEFINES += -D__INSIDE_RTEMS_BSD_TCPIP_STACK__ + +This is equivalent to the following list of definitions. Early versions of the +RTEMS BSD network stack required that all of these be defined. + +.. code-block:: makefile + + -D_COMPILING_BSD_KERNEL_ -DKERNEL -DINET -DNFS \ + -DDIAGNOSTIC -DBOOTP_COMPAT + +Defining these macros tells the network header files that the driver is to be +compiled with extended visibility into the network stack. This is in sharp +contrast to applications that simply use the network stack. Applications do +not require this level of visibility and should stick to the portable +application level API. + +As a direct result of being logically internal to the network stack, network +drivers use the BSD memory allocation routines This means, for example, that +malloc takes three arguments. See the SONIC device driver +(:file:`c/src/lib/libchip/network/sonic.c`) for an example of this. Because of +this, network drivers should not include ````. Doing so will result +in conflicting definitions of ``malloc()``. + +*Application level* code including network servers such as the FTP daemon are +*not* part of the BSD kernel network code and should not be compiled with the +BSD network flags. They should include ```` and not define the +network stack visibility macros. + +Write the Driver Attach Function +================================ + +The driver attach function is responsible for configuring the driver and making +the connection between the network stack and the driver. + +Driver attach functions take a pointer to an ``rtems_bsdnet_ifconfig`` +structure as their only argument. and set the driver parameters based on the +values in this structure. If an entry in the configuration structure is zero +the attach function chooses an appropriate default value for that parameter. + +The driver should then set up several fields in the ifnet structure in the +device-dependent data structure supplied and maintained by the driver: + +``ifp->if_softc`` + Pointer to the device-dependent data. The first entry in the + device-dependent data structure must be an ``arpcom`` structure. + +``ifp->if_name`` + The name of the device. The network stack uses this string and the device + number for device name lookups. The device name should be obtained from + the ``name`` entry in the configuration structure. + +``ifp->if_unit`` + The device number. The network stack uses this number and the device name + for device name lookups. For example, if ``ifp->if_name`` is ``scc`` and + ``ifp->if_unit`` is ``1``, the full device name would be ``scc1``. The + unit number should be obtained from the 'name' entry in the configuration + structure. + +``ifp->if_mtu`` + The maximum transmission unit for the device. For Ethernet devices this + value should almost always be 1500. + +``ifp->if_flags`` + The device flags. Ethernet devices should set the flags to + ``IFF_BROADCAST|IFF_SIMPLEX``, indicating that the device can broadcast + packets to multiple destinations and does not receive and transmit at the + same time. + +``ifp->if_snd.ifq_maxlen`` + The maximum length of the queue of packets waiting to be sent to the + driver. This is normally set to ``ifqmaxlen``. + +``ifp->if_init`` + The address of the driver initialization function. + +``ifp->if_start`` + The address of the driver start function. + +``ifp->if_ioctl`` + The address of the driver ioctl function. + +``ifp->if_output`` + The address of the output function. Ethernet devices should set this to + ``ether_output``. + +RTEMS provides a function to parse the driver name in the configuration +structure into a device name and unit number. + +.. code-block:: c + + int rtems_bsdnet_parse_driver_name ( + const struct rtems_bsdnet_ifconfig *config, + char **namep + ); + +The function takes two arguments; a pointer to the configuration structure and +a pointer to a pointer to a character. The function parses the configuration +name entry, allocates memory for the driver name, places the driver name in +this memory, sets the second argument to point to the name and returns the unit +number. On error, a message is printed and ``-1`` is returned. + +Once the attach function has set up the above entries it must link the driver +data structure onto the list of devices by calling ``if_attach``. Ethernet +devices should then call ``ether_ifattach``. Both functions take a pointer to +the device's ``ifnet`` structure as their only argument. + +The attach function should return a non-zero value to indicate that the driver +has been successfully configured and attached. + +Write the Driver Start Function. +================================ + +This function is called each time the network stack wants to start the +transmitter. This occures whenever the network stack adds a packet to a +device's send queue and the ``IFF_OACTIVE`` bit in the device's ``if_flags`` is +not set. + +For many devices this function need only set the ``IFF_OACTIVE`` bit in the +``if_flags`` and send an event to the transmit task indicating that a packet is +in the driver transmit queue. + +Write the Driver Initialization Function. +========================================= + +This function should initialize the device, attach to interrupt handler, and +start the driver transmit and receive tasks. The function + +.. code-block:: c + + rtems_id + rtems_bsdnet_newproc (char *name, + int stacksize, + void(*entry)(void *), + void *arg); + +should be used to start the driver tasks. + +Note that the network stack may call the driver initialization function more +than once. Make sure multiple versions of the receive and transmit tasks are +not accidentally started. + +Write the Driver Transmit Task +============================== + +This task is reponsible for removing packets from the driver send queue and +sending them to the device. The task should block waiting for an event from +the driver start function indicating that packets are waiting to be +transmitted. When the transmit task has drained the driver send queue the task +should clear the ``IFF_OACTIVE`` bit in ``if_flags`` and block until another +outgoing packet is queued. + +Write the Driver Receive Task +============================= + +This task should block until a packet arrives from the device. If the device +is an Ethernet interface the function ``ether_input`` should be called to +forward the packet to the network stack. The arguments to ``ether_input`` are +a pointer to the interface data structure, a pointer to the ethernet header and +a pointer to an mbuf containing the packet itself. + +Write the Driver Interrupt Handler +================================== + +A typical interrupt handler will do nothing more than the hardware manipulation +required to acknowledge the interrupt and send an RTEMS event to wake up the +driver receive or transmit task waiting for the event. Network interface +interrupt handlers must not make any calls to other network routines. + +Write the Driver IOCTL Function +=============================== + +This function handles ioctl requests directed at the device. The ioctl +commands which must be handled are: + +``SIOCGIFADDR`` + +``SIOCSIFADDR`` + If the device is an Ethernet interface these commands should be passed on + to ``ether_ioctl``. + +``SIOCSIFFLAGS`` + This command should be used to start or stop the device, depending on the + state of the interface ``IFF_UP`` and ``IFF_RUNNING`` bits in ``if_flags``: + + ``IFF_RUNNING`` + Stop the device. + + ``IFF_UP`` + Start the device. + + ``IFF_UP|IFF_RUNNING`` + Stop then start the device. + + ``0`` + Do nothing. + +Write the Driver Statistic-Printing Function +============================================ + +This function should print the values of any statistic/diagnostic counters the +network driver may use. The driver ioctl function should call the +statistic-printing function when the ioctl command is ``SIO_RTEMS_SHOW_STATS``. diff --git a/legacy-networking/preface.rst b/legacy-networking/preface.rst new file mode 100644 index 0000000..6926960 --- /dev/null +++ b/legacy-networking/preface.rst @@ -0,0 +1,38 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. COMMENT: Written by Eric Norum +.. Copyright (C) 1988, 2002 On-Line Applications Research Corporation (OAR) + +Preface +####### + +This document describes the RTEMS specific parts of the FreeBSD TCP/IP stack. +Much of this documentation was written by Eric Norum (eric@skatter.usask.ca) of +the Saskatchewan Accelerator Laboratory who also ported the FreeBSD TCP/IP +stack to RTEMS. + +The following is a list of resources which should be useful in trying to +understand Ethernet: + +- *Charles Spurgeon's Ethernet Web Site* + "This site provides extensive information about Ethernet (IEEE 802.3) local + area network (LAN) technology. Including the original 10 Megabit per second + (Mbps) system, the 100 Mbps Fast Ethernet system (802.3u), and the Gigabit + Ethernet system (802.3z)." The URL is: + (http://www.ethermanage.com/ethernet/ethernet.html) + +- *TCP/IP Illustrated, Volume 1 : The Protocols* + by W. Richard Stevens (ISBN: 0201633469) + This book provides detailed introduction to TCP/IP and includes diagnostic + programs which are publicly available. + +- *TCP/IP Illustrated, Volume 2 : The Implementation* + by W. Richard Stevens and Gary Wright (ISBN: 020163354X) + This book focuses on implementation issues regarding TCP/IP. The + treat for RTEMS users is that the implementation covered is the BSD + stack with most of the source code described in detail. + +- *UNIX Network Programming, Volume 1 : 2nd Edition* + by W. Richard Stevens (ISBN: 0-13-490012-X) + This book describes how to write basic TCP/IP applications, again with primary + focus on the BSD stack. diff --git a/legacy-networking/testing_the_driver.rst b/legacy-networking/testing_the_driver.rst new file mode 100644 index 0000000..dbd1163 --- /dev/null +++ b/legacy-networking/testing_the_driver.rst @@ -0,0 +1,299 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. COMMENT: Text Written by Jake Janovetz +.. Copyright (C) 1988, 2002 On-Line Applications Research Corporation (OAR) + +Testing the Driver +################## + +Preliminary Setup +================= + +The network used to test the driver should include at least: + +- The hardware on which the driver is to run. It makes testing much easier if + you can run a debugger to control the operation of the target machine. + +- An Ethernet network analyzer or a workstation with an 'Ethernet snoop' + program such as ``ethersnoop`` or ``tcpdump``. + +- A workstation. + +During early debug, you should consider putting the target, workstation, and +snooper on a small network by themselves. This offers a few advantages: + +- There is less traffic to look at on the snooper and for the target to process + while bringing the driver up. + +- Any serious errors will impact only your small network not a building or + campus network. You want to avoid causing any unnecessary problems. + +- Test traffic is easier to repeatably generate. + +- Performance measurements are not impacted by other systems on the network. + +Debug Output +============ + +There are a number of sources of debug output that can be enabled to aid in +tracing the behavior of the network stack. The following is a list of them: + +- mbuf activity + There are commented out calls to ``printf`` in the file ``sys/mbuf.h`` in the + network stack code. Uncommenting these lines results in output when mbuf's + are allocated and freed. This is very useful for finding memory leaks. + +- TX and RX queuing + There are commented out calls to ``printf`` in the file ``net/if.h`` in the + network stack code. Uncommenting these lines results in output when packets + are placed on or removed from one of the transmit or receive packet queues. + These queues can be viewed as the boundary line between a device driver and + the network stack. If the network stack is enqueuing packets to be + transmitted that the device driver is not dequeuing, then that is indicative + of a problem in the transmit side of the device driver. Conversely, if the + device driver is enqueueing packets as it receives them (via a call to + ``ether_input``) and they are not being dequeued by the network stack, then + there is a problem. This situation would likely indicate that the network + server task is not running. + +- TCP state transitions + + In the unlikely event that one would actually want to see TCP state + transitions, the ``TCPDEBUG`` macro can be defined in the file + ``opt_tcpdebug.h``. This results in the routine ``tcp_trace()`` being called + by the network stack and the state transitions logged into the ``tcp_debug`` + data structure. If the variable ``tcpconsdebug`` in the file + ``netinet/tcp_debug.c`` is set to ``1``, then the state transitions will also + be printed to the console. + +Monitor Commands +================ + +There are a number of command available in the shell / monitor to aid in +tracing the behavior of the network stack. The following is a list of them: + +- ``inet`` + This command shows the current routing information for the TCP/IP + stack. Following is an example showing the output of this command. + + .. code-block:: shell + + Destination Gateway/Mask/Hw Flags Refs Use Expire Interface + 10.0.0.0 255.0.0.0 U 0 0 17 smc1 + 127.0.0.1 127.0.0.1 UH 0 0 0 lo0 + + In this example, there is only one network interface with an IP address of + 10.8.1.1. This link is currently not up. Two routes that are shown are the + default routes for the Ethernet interface (10.0.0.0) and the loopback + interface (127.0.0.1). Since the stack comes from BSD, this command is very + similar to the netstat command. For more details on the network routing + please look the following URL: + (http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/network-routing.html) + For a quick reference to the flags, see the table below: + + '``U``' + Up: The route is active. + + '``H``' + Host: The route destination is a single host. + + '``G``' + Gateway: Send anything for this destination on to this remote system, + which will figure out from there where to send it. + + '``S``' + Static: This route was configured manually, not automatically generated + by the system. + + '``C``' + Clone: Generates a new route based upon this route for machines we + connect to. This type of route is normally used for local networks. + + '``W``' + WasCloned: Indicated a route that was auto-configured based upon a local + area network (Clone) route. + + '``L``' + Link: Route involves references to Ethernet hardware. + +- ``mbuf`` + This command shows the current MBUF statistics. An example of the command is + shown below: + + .. code-block:: shell + + ************ MBUF STATISTICS ************ + mbufs:4096 clusters: 256 free: 241 + drops: 0 waits: 0 drains: 0 + free:4080 data:16 header:0 socket:0 + pcb:0 rtable:0 htable:0 atable:0 + soname:0 soopts:0 ftable:0 rights:0 + ifaddr:0 control:0 oobdata:0 + +- ``if`` + This command shows the current statistics for your Ethernet driver as long as + the ioctl hook ``SIO_RTEMS_SHOW_STATS`` has been implemented. Below is an + example: + + .. code-block:: shell + + ************ INTERFACE STATISTICS ************ + ***** smc1 ***** + Ethernet Address: 00:12:76:43:34:25 + Address:10.8.1.1 Broadcast Address:10.255.255.255 Net mask:255.0.0.0 + Flags: Up Broadcast Running Simplex + Send queue limit:50 length:0 Dropped:0 + SMC91C111 RTEMS driver A0.01 11/03/2002 Ian Caddy (ianc@microsol.iinet.net.au) + Rx Interrupts:0 Not First:0 Not Last:0 + Giant:0 Runt:0 Non-octet:0 + Bad CRC:0 Overrun:0 Collision:0 + Tx Interrupts:2 Deferred:0 Missed Hearbeat:0 + No Carrier:0 Retransmit Limit:0 Late Collision:0 + Underrun:0 Raw output wait:0 Coalesced:0 + Coalesce failed:0 Retries:0 + ***** lo0 ***** + Address:127.0.0.1 Net mask:255.0.0.0 + Flags: Up Loopback Running Multicast + Send queue limit:50 length:0 Dropped:0 + +- ``ip`` + This command show the IP statistics for the currently configured interfaces. + +- ``icmp`` + This command show the ICMP statistics for the currently configured interfaces. + +- ``tcp`` + This command show the TCP statistics for the currently configured interfaces. + +- ``udp`` + This command show the UDP statistics for the currently configured interfaces. + +Driver basic operation +====================== + +The network demonstration program ``netdemo`` may be used for these tests. + +- Edit ``networkconfig.h`` to reflect the values for your network. + +- Start with ``RTEMS_USE_BOOTP`` not defined. + +- Edit ``networkconfig.h`` to configure the driver with an explicit Ethernet + and Internet address and with reception of broadcast packets disabled: Verify + that the program continues to run once the driver has been attached. + +- Issue a '``u``' command to send UDP packets to the 'discard' port. Verify + that the packets appear on the network. + +- Issue a '``s``' command to print the network and driver statistics. + +- On a workstation, add a static route to the target system. + +- On that same workstation try to 'ping' the target system. + Verify that the ICMP echo request and reply packets appear on the net. + +- Remove the static route to the target system. Modify ``networkconfig.h`` to + attach the driver with reception of broadcast packets enabled. Try to 'ping' + the target system again. Verify that ARP request/reply and ICMP echo + request/reply packets appear on the net. + +- Issue a '``t``' command to send TCP packets to the 'discard' port. Verify + that the packets appear on the network. + +- Issue a '``s``' command to print the network and driver statistics. + +- Verify that you can telnet to ports 24742 and 24743 on the target system from + one or more workstations on your network. + +BOOTP/DHCP operation +==================== + +Set up a BOOTP/DHCP server on the network. Set define ``RTEMS USE_BOOT`` in +``networkconfig.h``. Run the ``netdemo`` test program. Verify that the target +system configures itself from the BOOTP/DHCP server and that all the above +tests succeed. + +Stress Tests +============ + +Once the driver passes the tests described in the previous section it should be +subjected to conditions which exercise it more thoroughly and which test its +error handling routines. + +Giant packets +------------- + +- Recompile the driver with ``MAXIMUM_FRAME_SIZE`` set to a smaller value, + say 514. + +- 'Ping' the driver from another workstation and verify that frames larger than + 514 bytes are correctly rejected. + +- Recompile the driver with ``MAXIMUM_FRAME_SIZE`` restored to 1518. + +Resource Exhaustion +------------------- + +- Edit ``networkconfig.h`` so that the driver is configured with just two + receive and transmit descriptors. + +- Compile and run the ``netdemo`` program. + +- Verify that the program operates properly and that you can still telnet to + both the ports. + +- Display the driver statistics (Console '``s``' command or telnet 'control-G' + character) and verify that: + + #. The number of transmit interrupts is non-zero. This indicates that all + transmit descriptors have been in use at some time. + + #. The number of missed packets is non-zero. This indicates that all receive + descriptors have been in use at some time. + +Cable Faults +------------ + +- Run the ``netdemo`` program. + +- Issue a '``u``' console command to make the target machine transmit a bunch + of UDP packets. + +- While the packets are being transmitted, disconnect and reconnect the network + cable. + +- Display the network statistics and verify that the driver has detected the + loss of carrier. + +- Verify that you can still telnet to both ports on the target machine. + +Throughput +---------- + +Run the ``ttcp`` network benchmark program. Transfer large amounts of data +(100's of megabytes) to and from the target system. + +The procedure for testing throughput from a host to an RTEMS target is as +follows: + + #. Download and start the ttcp program on the Target. + + #. In response to the ``ttcp`` prompt, enter ``-s -r``. The meaning of these + flags is described in the ``ttcp.1`` manual page found in the ``ttcp_orig`` + subdirectory. + + #. On the host run ``ttcp -s -t <>`` + +The procedure for testing throughput from an RTEMS target to a Host is as +follows: + + #. On the host run ``ttcp -s -r``. + + #. Download and start the ttcp program on the Target. + + #. In response to the ``ttcp`` prompt, enter ``-s -t <>``. You need to type the IP address of the + host unless your Target is talking to your Domain Name Server. + +To change the number of buffers, the buffer size, etc. you just add the extra +flags to the ``-t`` machine as specified in the ``ttcp.1`` manual page found in +the ``ttcp_orig`` subdirectory. diff --git a/legacy-networking/using_networking_rtems_app.rst b/legacy-networking/using_networking_rtems_app.rst new file mode 100644 index 0000000..0d3e245 --- /dev/null +++ b/legacy-networking/using_networking_rtems_app.rst @@ -0,0 +1,851 @@ +.. SPDX-License-Identifier: CC-BY-SA-4.0 + +.. COMMENT: Written by Eric Norum +.. Copyright (C) 1988, 2002 On-Line Applications Research Corporation (OAR) + +Using Networking in an RTEMS Application +######################################## + +Makefile changes +================ + +Including the required managers +------------------------------- + +The FreeBSD networking code requires several RTEMS managers in the application: + +.. code-block:: makefile + + MANAGERS = io event semaphore + +Increasing the size of the heap +------------------------------- + +The networking tasks allocate a lot of memory. For most applications the heap +should be at least 256 kbytes. The amount of memory set aside for the heap can +be adjusted by setting the ``CFLAGS_LD`` definition as shown below: + +.. code-block:: makefile + + CFLAGS_LD += -Wl,--defsym -Wl,HeapSize=0x80000 + +This sets aside 512 kbytes of memory for the heap. + +System Configuration +==================== + +The networking tasks allocate some RTEMS objects. These must be accounted for +in the application configuration table. The following lists the requirements. + +*TASKS* + One network task plus a receive and transmit task for each device. + +*SEMAPHORES* + One network semaphore plus one syslog mutex semaphore if the application + uses openlog/syslog. + +*EVENTS* + The network stack uses ``RTEMS_EVENT_24`` and ``RTEMS_EVENT_25``. This has + no effect on the application configuration, but application tasks which + call the network functions should not use these events for other purposes. + +Initialization +============== + +Additional include files +------------------------ + +The source file which declares the network configuration structures and calls +the network initialization function must include + +.. code-block:: c + + #include + +Network Configuration +--------------------- + +The network configuration is specified by declaring and initializing the +``rtems_bsdnet_config`` structure. + +.. code-block:: c + + struct rtems_bsdnet_config { + /* + * This entry points to the head of the ifconfig chain. + */ + struct rtems_bsdnet_ifconfig *ifconfig; + /* + * This entry should be rtems_bsdnet_do_bootp if BOOTP + * is being used to configure the network, and NULL + * if BOOTP is not being used. + */ + void (*bootp)(void); + /* + * The remaining items can be initialized to 0, in + * which case the default value will be used. + */ + rtems_task_priority network_task_priority; /* 100 */ + unsigned long mbuf_bytecount; /* 64 kbytes */ + unsigned long mbuf_cluster_bytecount; /* 128 kbytes */ + char *hostname; /* BOOTP */ + char *domainname; /* BOOTP */ + char *gateway; /* BOOTP */ + char *log_host; /* BOOTP */ + char *name_server[3]; /* BOOTP */ + char *ntp_server[3]; /* BOOTP */ + unsigned long sb_efficiency; /* 2 */ + /* UDP TX: 9216 bytes */ + unsigned long udp_tx_buf_size; + /* UDP RX: 40 * (1024 + sizeof(struct sockaddr_in)) */ + unsigned long udp_rx_buf_size; + /* TCP TX: 16 * 1024 bytes */ + unsigned long tcp_tx_buf_size; + /* TCP TX: 16 * 1024 bytes */ + unsigned long tcp_rx_buf_size; + /* Default Network Tasks CPU Affinity */ + #ifdef RTEMS_SMP + const cpu_set_t *network_task_cpuset; + size_t network_task_cpuset_size; + #endif + }; + +The structure entries are described in the following table. If your +application uses BOOTP/DHCP to obtain network configuration information and if +you are happy with the default values described below, you need to provide only +the first two entries in this structure. + +``struct rtems_bsdnet_ifconfig *ifconfig`` + A pointer to the first configuration structure of the first network device. + This structure is described in the following section. You must provide a + value for this entry since there is no default value for it. + +``void (*bootp)(void)`` + This entry should be set to ``rtems_bsdnet_do_bootp`` if your application + by default uses the BOOTP/DHCP client protocol to obtain network + configuration information. It should be set to ``NULL`` if your + application does not use BOOTP/DHCP. You can also use + ``rtems_bsdnet_do_bootp_rootfs`` to have a set of standard files created + with the information return by the BOOTP/DHCP protocol. The IP address is + added to :file:`/etc/hosts` with the host name and domain returned. If no + host name or domain is returned ``me.mydomain`` is used. The BOOTP/DHCP + server's address is also added to :file:`/etc/hosts`. The domain name + server listed in the BOOTP/DHCP information are added to + :file:`/etc/resolv.conf`. A``search`` record is also added if a domain is + returned. The files are created if they do not exist. The default + ``rtems_bsdnet_do_bootp`` and ``rtems_bsdnet_do_bootp_rootfs`` handlers + will loop for-ever waiting for a BOOTP/DHCP server to respond. If an error + is detected such as not valid interface or valid hardware address the + target will reboot allowing any hardware reset to correct itself. You can + provide your own custom handler which allows you to perform an + initialization that meets your specific system requirements. For example + you could try BOOTP/DHCP then enter a configuration tool if no server is + found allowing the user to switch to a static configuration. + +``int network_task_priority`` + The priority at which the network task and network device + receive and transmit tasks will run. + If a value of 0 is specified the tasks will run at priority 100. + +``unsigned long mbuf_bytecount`` + The number of bytes to allocate from the heap for use as mbufs. + If a value of 0 is specified, 64 kbytes will be allocated. + +``unsigned long mbuf_cluster_bytecount`` + The number of bytes to allocate from the heap for use as mbuf clusters. + If a value of 0 is specified, 128 kbytes will be allocated. + +``char *hostname`` + The host name of the system. + If this, or any of the following, entries are ``NULL`` the value + may be obtained from a BOOTP/DHCP server. + +``char *domainname`` + The name of the Internet domain to which the system belongs. + +``char *gateway`` + The Internet host number of the network gateway machine, specified in + 'dotted decimal' (``129.128.4.1``) form. + +``char *log_host`` + The Internet host number of the machine to which ``syslog`` messages will + be sent. + +``char *name_server[3]`` + The Internet host numbers of up to three machines to be used as Internet + Domain Name Servers. + +``char *ntp_server[3]`` + The Internet host numbers of up to three machines to be used as + Network Time Protocol (NTP) Servers. + +``unsigned long sb_efficiency`` + This is the first of five configuration parameters related to the amount of + memory each socket may consume for buffers. The TCP/IP stack reserves + buffers (e.g. mbufs) for each open socket. The TCP/IP stack has different + limits for the transmit and receive buffers associated with each TCP and + UDP socket. By tuning these parameters, the application developer can make + trade-offs between memory consumption and performance. The default + parameters favor performance over memory consumption. See + http://www.rtems.org/ml/rtems-users/2004/february/msg00200.html for more + details but note that after the RTEMS 4.8 release series, the + ``sb_efficiency`` default was changed from ``8`` to ``2``. The user should + also be aware of the ``SO_SNDBUF`` and ``SO_RCVBUF`` IO control operations. + These can be used to specify the send and receive buffer sizes for a + specific socket. There is no standard IO control to change the + ``sb_efficiency`` factor. The ``sb_efficiency`` parameter is a buffering + factor used in the implementation of the TCP/IP stack. The default is + ``2`` which indicates double buffering. When allocating memory for each + socket, this number is multiplied by the buffer sizes for that socket. + +``unsigned long udp_tx_buf_size`` + This configuration parameter specifies the maximum amount of buffer memory + which may be used for UDP sockets to transmit with. The default size is + 9216 bytes which corresponds to the maximum datagram size. + +``unsigned long udp_rx_buf_size`` + This configuration parameter specifies the maximum amount of buffer memory + which may be used for UDP sockets to receive into. The default size is the + following length in bytes: + + .. code-block:: c + + 40 * (1024 + sizeof(struct sockaddr_in)) + +``unsigned long tcp_tx_buf_size`` + This configuration parameter specifies the maximum amount of buffer memory + which may be used for TCP sockets to transmit with. The default size is + sixteen kilobytes. + +``unsigned long tcp_rx_buf_size`` + This configuration parameter specifies the maximum amount of buffer memory + which may be used for TCP sockets to receive into. The default size is + sixteen kilobytes. + +``const cpu_set_t *network_task_cpuset`` + This configuration parameter specifies the CPU affinity of the network + task. If set to ``0`` the network task can be scheduled on any CPU. Only + available in SMP configurations. + +``size_t network_task_cpuset_size`` + This configuration parameter specifies the size of the + ``network_task_cpuset`` used. Only available in SMP configurations. + +In addition, the following fields in the ``rtems_bsdnet_ifconfig`` are of +interest. + +*int port* + The I/O port number (ex: 0x240) on which the external Ethernet can be + accessed. + +*int irno* + The interrupt number of the external Ethernet controller. + +*int bpar* + The address of the shared memory on the external Ethernet controller. + +Network device configuration +---------------------------- + +Network devices are specified and configured by declaring and initializing a +``struct rtems_bsdnet_ifconfig`` structure for each network device. + +The structure entries are described in the following table. An application +which uses a single network interface, gets network configuration information +from a BOOTP/DHCP server, and uses the default values for all driver parameters +needs to initialize only the first two entries in the structure. + +``char *name`` + The full name of the network device. This name consists of the driver name + and the unit number (e.g. ``"scc1"``). The ``bsp.h`` include file usually + defines ``RTEMS_BSP_NETWORK_DRIVER_NAME`` as the name of the primary (or + only) network driver. + +``int (*attach)(struct rtems_bsdnet_ifconfig *conf)`` + + The address of the driver ``attach`` function. The network initialization + function calls this function to configure the driver and attach it to the + network stack. The ``bsp.h`` include file usually defines + ``RTEMS_BSP_NETWORK_DRIVER_ATTACH`` as the name of the attach function of + the primary (or only) network driver. + +``struct rtems_bsdnet_ifconfig *next`` + A pointer to the network device configuration structure for the next + network interface, or ``NULL`` if this is the configuration structure of + the last network interface. + +``char *ip_address`` + The Internet address of the device, specified in 'dotted decimal' + (``129.128.4.2``) form, or ``NULL`` if the device configuration information + is being obtained from a BOOTP/DHCP server. + +``char *ip_netmask`` + The Internet inetwork mask of the device, specified in 'dotted decimal' + (``255.255.255.0``) form, or ``NULL`` if the device configuration + information is being obtained from a BOOTP/DHCP server. + +``void *hardware_address`` + The hardware address of the device, or ``NULL`` if the driver is to obtain + the hardware address in some other way (usually by reading it from the + device or from the bootstrap ROM). + +``int ignore_broadcast`` + Zero if the device is to accept broadcast packets, non-zero if the device + is to ignore broadcast packets. + +``int mtu`` + The maximum transmission unit of the device, or zero if the driver is to + choose a default value (typically 1500 for Ethernet devices). + +``int rbuf_count`` + The number of receive buffers to use, or zero if the driver is to choose a + default value + +``int xbuf_count`` + The number of transmit buffers to use, or zero if the driver is to choose a + default value Keep in mind that some network devices may use 4 or more + transmit descriptors for a single transmit buffer. + +A complete network configuration specification can be as simple as the one +shown in the following example. This configuration uses a single network +interface, gets network configuration information from a BOOTP/DHCP server, and +uses the default values for all driver parameters. + +.. code-block:: c + + static struct rtems_bsdnet_ifconfig netdriver_config = { + RTEMS_BSP_NETWORK_DRIVER_NAME, + RTEMS_BSP_NETWORK_DRIVER_ATTACH + }; + struct rtems_bsdnet_config rtems_bsdnet_config = { + &netdriver_config, + rtems_bsdnet_do_bootp, + }; + +Network initialization +---------------------- + +The networking tasks must be started before any network I/O operations can be +performed. This is done by calling: + +.. code-block:: c + + rtems_bsdnet_initialize_network (); + +This function is declared in ``rtems/rtems_bsdnet.h``. t returns 0 on success +and -1 on failure with an error code in ``errno``. It is not possible to undo +the effects of a partial initialization, though, so the function can be called +only once irregardless of the return code. Consequently, if the condition for +the failure can be corrected, the system must be reset to permit another +network initialization attempt. + +Application Programming Interface +================================= + +The RTEMS network package provides almost a complete set of BSD network +services. The network functions work like their BSD counterparts with the +following exceptions: + +- A given socket can be read or written by only one task at a time. + +- The ``select`` function only works for file descriptors associated with + sockets. + +- You must call ``openlog`` before calling any of the ``syslog`` functions. + +- *Some of the network functions are not thread-safe.* For example the + following functions return a pointer to a static buffer which remains valid + only until the next call: + + ``gethostbyaddr`` + ``gethostbyname`` + ``inet_ntoa`` (``inet_ntop`` is thread-safe, though). + +- The RTEMS network package gathers statistics. + +- Addition of a mechanism to "tap onto" an interface and monitor every packet + received and transmitted. + +- Addition of ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP`` socket options. + +Some of the new features are discussed in more detail in the following +sections. + +Network Statistics +------------------ + +There are a number of functions to print statistics gathered by the network +stack. These function are declared in ``rtems/rtems_bsdnet.h``. + +``rtems_bsdnet_show_if_stats`` + Display statistics gathered by network interfaces. + +``rtems_bsdnet_show_ip_stats`` + Display IP packet statistics. + +``rtems_bsdnet_show_icmp_stats`` + Display ICMP packet statistics. + +``rtems_bsdnet_show_tcp_stats`` + Display TCP packet statistics. + +``rtems_bsdnet_show_udp_stats`` + Display UDP packet statistics. + +``rtems_bsdnet_show_mbuf_stats`` + Display mbuf statistics. + +``rtems_bsdnet_show_inet_routes`` + Display the routing table. + +Tapping Into an Interface +------------------------- + +RTEMS add two new ioctls to the BSD networking code, ``SIOCSIFTAP`` and +``SIOCGIFTAP``. These may be used to set and get a *tap function*. The tap +function will be called for every Ethernet packet received by the interface. + +These are called like other interface ioctls, such as ``SIOCSIFADDR``. When +setting the tap function with ``SIOCSIFTAP``, set the ifr_tap field of the +ifreq struct to the tap function. When retrieving the tap function with +``SIOCGIFTAP``, the current tap function will be returned in the ifr_tap field. +To stop tapping packets, call ``SIOCSIFTAP`` with a ``ifr_tap`` field of ``0``. + +The tap function is called like this: + +.. code-block:: c + + int tap (struct ifnet *, struct ether_header *, struct mbuf *) + +The tap function should return ``1`` if the packet was fully handled, in which +case the caller will simply discard the mbuf. The tap function should return +``0`` if the packet should be passed up to the higher networking layers. + +The tap function is called with the network semaphore locked. It must not make +any calls on the application levels of the networking level itself. It is safe +to call other non-networking RTEMS functions. + +Socket Options +-------------- + +RTEMS adds two new ``SOL_SOCKET`` level options for ``setsockopt`` and +``getsockopt``: ``SO_SNDWAKEUP`` and ``SO_RCVWAKEUP``. For both, the option +value should point to a sockwakeup structure. The sockwakeup structure has the +following fields: + +.. code-block:: c + + void (*sw_pfn) (struct socket *, caddr_t); + caddr_t sw_arg; + +These options are used to set a callback function to be called when, for +example, there is data available from the socket (``SO_RCVWAKEUP``) and when +there is space available to accept data written to the socket +(``SO_SNDWAKEUP``). + +If ``setsockopt`` is called with the ``SO_RCVWAKEUP`` option, and the +``sw_pfn`` field is not zero, then when there is data available to be read from +the socket, the function pointed to by the ``sw_pfn`` field will be called. A +pointer to the socket structure will be passed as the first argument to the +function. The ``sw_arg`` field set by the ``SO_RCVWAKEUP`` call will be passed +as the second argument to the function. + +If ``setsockopt`` is called with the ``SO_SNDWAKEUP`` function, and the +``sw_pfn`` field is not zero, then when there is space available to accept data +written to the socket, the function pointed to by the ``sw_pfn`` field will be +called. The arguments passed to the function will be as with ``SO_SNDWAKEUP``. + +When the function is called, the network semaphore will be locked and the +callback function runs in the context of the networking task. The function +must be careful not to call any networking functions. It is OK to call an +RTEMS function; for example, it is OK to send an RTEMS event. + +The purpose of these callback functions is to permit a more efficient +alternative to the select call when dealing with a large number of sockets. + +The callbacks are called by the same criteria that the select function uses for +indicating "ready" sockets. In Stevens *Unix Network Programming* on page +153-154 in the section "Under what Conditions Is a Descriptor Ready?" you will +find the definitive list of conditions for readable and writable that also +determine when the functions are called. + +When the number of received bytes equals or exceeds the socket receive buffer +"low water mark" (default 1 byte) you get a readable callback. If there are 100 +bytes in the receive buffer and you only read 1, you will not immediately get +another callback. However, you will get another callback after you read the +remaining 99 bytes and at least 1 more byte arrives. Using a non-blocking +socket you should probably read until it produces error ``EWOULDBLOCK`` and +then allow the readable callback to tell you when more data has arrived. +(Condition 1.a.) + +For sending, when the socket is connected and the free space becomes at or +above the "low water mark" for the send buffer (default 4096 bytes) you will +receive a writable callback. You don't get continuous callbacks if you don't +write anything. Using a non-blocking write socket, you can then call write +until it returns a value less than the amount of data requested to be sent or +it produces error ``EWOULDBLOCK`` (indicating buffer full and no longer +writable). When this happens you can try the write again, but it is often +better to go do other things and let the writable callback tell you when space +is available to send again. You only get a writable callback when the free +space transitions to above the "low water mark" and not every time you write to +a non-full send buffer. (Condition 2.a.) + +The remaining conditions enumerated by Stevens handle the fact that sockets +become readable and/or writable when connects, disconnects and errors occur, +not just when data is received or sent. For example, when a server "listening" +socket becomes readable it indicates that a client has connected and accept can +be called without blocking, not that network data was received (Condition 1.c). + +Adding an IP Alias +------------------ + +The following code snippet adds an IP alias: + +.. code-block:: c + + void addAlias(const char *pName, const char *pAddr, const char *pMask) + { + struct ifaliasreq aliasreq; + struct sockaddr_in *in; + + /* initialize alias request */ + memset(&aliasreq, 0, sizeof(aliasreq)); + sprintf(aliasreq.ifra_name, pName); + + /* initialize alias address */ + in = (struct sockaddr_in *)&aliasreq.ifra_addr; + in->sin_family = AF_INET; + in->sin_len = sizeof(aliasreq.ifra_addr); + in->sin_addr.s_addr = inet_addr(pAddr); + + /* initialize alias mask */ + in = (struct sockaddr_in *)&aliasreq.ifra_mask; + in->sin_family = AF_INET; + in->sin_len = sizeof(aliasreq.ifra_mask); + in->sin_addr.s_addr = inet_addr(pMask); + + /* call to setup the alias */ + rtems_bsdnet_ifconfig(pName, SIOCAIFADDR, &aliasreq); + } + +Thanks to Mike Seirs for this example code. + +Adding a Default Route +---------------------- + +The function provided in this section is functionally equivalent to the command +``route add default gw yyy.yyy.yyy.yyy``: + +.. code-block:: c + + void mon_ifconfig(int argc, char *argv[], unsigned32 command_arg, bool verbose) + { + struct sockaddr_in ipaddr; + struct sockaddr_in dstaddr; + struct sockaddr_in netmask; + struct sockaddr_in broadcast; + char *iface; + int f_ip = 0; + int f_ptp = 0; + int f_netmask = 0; + int f_up = 0; + int f_down = 0; + int f_bcast = 0; + int cur_idx; + int rc; + int flags; + + bzero((void*) &ipaddr, sizeof(ipaddr)); + bzero((void*) &dstaddr, sizeof(dstaddr)); + bzero((void*) &netmask, sizeof(netmask)); + bzero((void*) &broadcast, sizeof(broadcast)); + ipaddr.sin_len = sizeof(ipaddr); + ipaddr.sin_family = AF_INET; + dstaddr.sin_len = sizeof(dstaddr); + dstaddr.sin_family = AF_INET; + netmask.sin_len = sizeof(netmask); + netmask.sin_family = AF_INET; + broadcast.sin_len = sizeof(broadcast); + broadcast.sin_family = AF_INET; + cur_idx = 0; + + if (argc <= 1) { + /* display all interfaces */ + iface = NULL; + cur_idx += 1; + } else { + iface = argv[1]; + if (isdigit(*argv[2])) { + if (inet_pton(AF_INET, argv[2], &ipaddr.sin_addr) < 0) { + printf("bad ip address: %s\n", argv[2]); + return; + } + f_ip = 1; + cur_idx += 3; + } else { + cur_idx += 2; + } + } + + if ((f_down !=0) && (f_ip != 0)) { + f_up = 1; + } + + while(argc > cur_idx) { + if (strcmp(argv[cur_idx], "up") == 0) { + f_up = 1; + if (f_down != 0) { + printf("Can't make interface up and down\n"); + } + } else if(strcmp(argv[cur_idx], "down") == 0) { + f_down = 1; + if (f_up != 0) { + printf("Can't make interface up and down\n"); + } + } else if(strcmp(argv[cur_idx], "netmask") == 0) { + if ((cur_idx + 1) >= argc) { + printf("No netmask address\n"); + return; + } + if (inet_pton(AF_INET, argv[cur_idx+1], &netmask.sin_addr) < 0) { + printf("bad netmask: %s\n", argv[cur_idx]); + return; + } + f_netmask = 1; + cur_idx += 1; + } else if(strcmp(argv[cur_idx], "broadcast") == 0) { + if ((cur_idx + 1) >= argc) { + printf("No broadcast address\n"); + return; + } + if (inet_pton(AF_INET, argv[cur_idx+1], &broadcast.sin_addr) < 0) { + printf("bad broadcast: %s\n", argv[cur_idx]); + return; + } + f_bcast = 1; + cur_idx += 1; + } else if(strcmp(argv[cur_idx], "pointopoint") == 0) { + if ((cur_idx + 1) >= argc) { + printf("No pointopoint address\n"); + return; + } + if (inet_pton(AF_INET, argv[cur_idx+1], &dstaddr.sin_addr) < 0) { + printf("bad pointopoint: %s\n", argv[cur_idx]); + return; + } + f_ptp = 1; + cur_idx += 1; + } else { + printf("Bad parameter: %s\n", argv[cur_idx]); + return; + } + cur_idx += 1; + } + + printf("ifconfig "); + + if (iface != NULL) { + printf("%s ", iface); + if (f_ip != 0) { + char str[256]; + inet_ntop(AF_INET, &ipaddr.sin_addr, str, 256); + printf("%s ", str); + } + if (f_netmask != 0) { + char str[256]; + inet_ntop(AF_INET, &netmask.sin_addr, str, 256); + printf("netmask %s ", str); + } + if (f_bcast != 0) { + char str[256]; + inet_ntop(AF_INET, &broadcast.sin_addr, str, 256); + printf("broadcast %s ", str); + } + if (f_ptp != 0) { + char str[256]; + inet_ntop(AF_INET, &dstaddr.sin_addr, str, 256); + printf("pointopoint %s ", str); + } + if (f_up != 0) { + printf("up\n"); + } else if (f_down != 0) { + printf("down\n"); + } else { + printf("\n"); + } + } + + if ((iface == NULL) || ((f_ip == 0) && (f_down == 0) && (f_up == 0))) { + rtems_bsdnet_show_if_stats(); + return; + } + + flags = 0; + if (f_netmask) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFNETMASK, &netmask); + if (rc < 0) { + printf("Could not set netmask: %s\n", strerror(errno)); + return; + } + } + if (f_bcast) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFBRDADDR, &broadcast); + if (rc < 0) { + printf("Could not set broadcast: %s\n", strerror(errno)); + return; + } + } + if (f_ptp) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFDSTADDR, &dstaddr); + if (rc < 0) { + printf("Could not set destination address: %s\n", strerror(errno)); + return; + } + flags |= IFF_POINTOPOINT; + } + + /* This must come _after_ setting the netmask, broadcast addresses */ + if (f_ip) { + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFADDR, &ipaddr); + if (rc < 0) { + printf("Could not set IP address: %s\n", strerror(errno)); + return; + } + } + if (f_up != 0) { + flags |= IFF_UP; + } + if (f_down != 0) { + printf("Warning: taking interfaces down is not supported\n"); + } + + rc = rtems_bsdnet_ifconfig(iface, SIOCSIFFLAGS, &flags); + if (rc < 0) { + printf("Could not set interface flags: %s\n", strerror(errno)); + return; + } + } + + void mon_route(int argc, char *argv[], unsigned32 command_arg, bool verbose) + { + int cmd; + struct sockaddr_in dst; + struct sockaddr_in gw; + struct sockaddr_in netmask; + int f_host; + int f_gw = 0; + int cur_idx; + int flags; + int rc; + + memset(&dst, 0, sizeof(dst)); + memset(&gw, 0, sizeof(gw)); + memset(&netmask, 0, sizeof(netmask)); + dst.sin_len = sizeof(dst); + dst.sin_family = AF_INET; + dst.sin_addr.s_addr = inet_addr("0.0.0.0"); + gw.sin_len = sizeof(gw); + gw.sin_family = AF_INET; + gw.sin_addr.s_addr = inet_addr("0.0.0.0"); + netmask.sin_len = sizeof(netmask); + netmask.sin_family = AF_INET; + netmask.sin_addr.s_addr = inet_addr("255.255.255.0"); + + if (argc < 2) { + rtems_bsdnet_show_inet_routes(); + return; + } + + if (strcmp(argv[1], "add") == 0) { + cmd = RTM_ADD; + } else if (strcmp(argv[1], "del") == 0) { + cmd = RTM_DELETE; + } else { + printf("invalid command: %s\n", argv[1]); + printf("\tit should be 'add' or 'del'\n"); + return; + } + + if (argc < 3) { + printf("not enough arguments\n"); + return; + } + + if (strcmp(argv[2], "-host") == 0) { + f_host = 1; + } else if (strcmp(argv[2], "-net") == 0) { + f_host = 0; + } else { + printf("Invalid type: %s\n", argv[1]); + printf("\tit should be '-host' or '-net'\n"); + return; + } + + if (argc < 4) { + printf("not enough arguments\n"); + return; + } + + inet_pton(AF_INET, argv[3], &dst.sin_addr); + + cur_idx = 4; + while(cur_idx < argc) { + if (strcmp(argv[cur_idx], "gw") == 0) { + if ((cur_idx +1) >= argc) { + printf("no gateway address\n"); + return; + } + f_gw = 1; + inet_pton(AF_INET, argv[cur_idx + 1], &gw.sin_addr); + cur_idx += 1; + } else if(strcmp(argv[cur_idx], "netmask") == 0) { + if ((cur_idx +1) >= argc) { + printf("no netmask address\n"); + return; + } + f_gw = 1; + inet_pton(AF_INET, argv[cur_idx + 1], &netmask.sin_addr); + cur_idx += 1; + } else { + printf("Unknown argument\n"); + return; + } + cur_idx += 1; + } + + flags = RTF_STATIC; + if (f_gw != 0) { + flags |= RTF_GATEWAY; + } + if (f_host != 0) { + flags |= RTF_HOST; + } + + rc = rtems_bsdnet_rtrequest(cmd, &dst, &gw, &netmask, flags, NULL); + if (rc < 0) { + printf("Error adding route\n"); + } + } + +Thanks to Jay Monkman for this example +code. + +Time Synchronization Using NTP +------------------------------ + +.. code-block:: c + + int rtems_bsdnet_synchronize_ntp (int interval, rtems_task_priority priority); + +If the interval argument is ``0`` the routine synchronizes the RTEMS +time-of-day clock with the first NTP server in the ``rtems_bsdnet_ntpserve`` +array and returns. The priority argument is ignored. + +If the interval argument is greater than 0, the routine also starts an RTEMS +task at the specified priority and polls the NTP server every 'interval' +seconds. NOTE: This mode of operation has not yet been implemented. + +On successful synchronization of the RTEMS time-of-day clock the routine +returns ``0``. If an error occurs a message is printed and the routine returns +``-1`` with an error code in errno. There is no timeout - if there is no +response from an NTP server the routine will wait forever. diff --git a/legacy-networking/wscript b/legacy-networking/wscript new file mode 100644 index 0000000..4063cd4 --- /dev/null +++ b/legacy-networking/wscript @@ -0,0 +1,7 @@ +from common.waf import cmd_configure as configure +from common.waf import cmd_build as build +from common.waf import cmd_options as options +from common.waf import spell +from common.waf import cmd_spell +from common.waf import linkcheck +from common.waf import cmd_linkcheck -- cgit v1.2.3