Add the "-c <count>" option to the "ping" command, allowing for
automatic termination after a specified number of packets.
When a number of packets is specified:
- if a serious error (i.e. length mismatch or content mismatch)
occurs, then the ping will be immediately terminated with the relevant
status code;
- if at least one response is received successfully, and all errors
are non-serious (i.e. timeouts or out-of-sequence responses), then
the ping will be terminated after the final response (or timeout)
with a success status;
- if no responses are received successfully, then the ping will be
terminated after the final timeout with ETIMEDOUT.
If no number of packets is specified, then the ping will continue
until manually interrupted.
Originally-implemented-by: Cedric Levasseur <cyr-ius@ipocus.net>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some UEFI network drivers provide a software UNDI interface which is
exposed via the Network Interface Identifier Protocol (NII), rather
than providing a Simple Network Protocol (SNP).
The UEFI platform firmware will usually include the SnpDxe driver,
which attaches to NII and provides an SNP interface. The SNP
interface is usually provided on the same handle as the underlying NII
device. This causes problems for our EFI driver model: when
efi_driver_connect() detaches existing drivers from the handle it will
cause the SNP interface to be uninstalled, and so our SNP driver will
not be able to attach to the handle. The platform firmware will
eventually reattach the SnpDxe driver and may attach us to the SNP
handle, but we have no way to prevent other drivers from attaching
first.
Fix by providing a driver which can attach directly to the NII
protocol, using the software UNDI interface to drive the network
device.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Under UEFI, reads from PCI configuration space may fail. If this
happens, we should return all-ones (which will mimic the behaviour of
an absent PCI device).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Propagate our modified EFI system table to any images loaded by the
image that we wrap, thereby allowing us to observe boot services calls
made by all subsequent EFI images.
Also show details of intercepted ExitBootServices() calls. When
wrapping is used, exiting boot services will almost certainly fail,
but this at least allows us to see when it happens.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Under some circumstances (e.g. if iPXE itself is booted via iSCSI, or
after an unclean reboot), the backend may not be in the expected
InitWait state when iPXE starts up.
There is no generic reset mechanism for Xenbus devices. Recent
versions of xen-netback will gracefully perform all of the required
steps if the frontend sets its state to Initialising. Older versions
(such as that found in XenServer 6.2.0) require the frontend to
transition through Closed before reaching Initialising.
Add a reset mechanism for netfront devices which does the following:
- read current backend state
- if backend state is anything other than InitWait, then set the
frontend state to Closed and wait for the backend to also reach
Closed
- set the frontend state to Initialising and wait for the backend to
reach InitWait.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Using version 1 grant tables limits guests to using 16TB of grantable
RAM, and prevents the use of subpage grants. Some versions of the Xen
hypervisor refuse to allow the grant table version to be set after the
first grant references have been created, so the loaded operating
system may be stuck with whatever choice we make here. We therefore
currently use version 2 grant tables, since they give the most
flexibility to the loaded OS.
Current versions (7.2.0) of the Windows PV drivers have no support for
version 2 grant tables, and will merrily create version 1 entries in
what the hypervisor believes to be a version 2 table. This causes
some confusion.
Avoid this problem by attempting to use version 1 tables, since
otherwise we may render Windows unable to boot.
Play nicely with other potential bootloaders by accepting either
version 1 or version 2 grant tables (if we are unable to set our
requested version).
Note that the use of version 1 tables on a 64-bit system introduces a
possible failure path in which a frame number cannot fit into the
32-bit field within the v1 structure. This in turn introduces
additional failure paths into netfront_transmit() and
netfront_refill_rx().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some EFI 1.10 systems (observed on an Apple iMac) do not allow us to
open the device path protocol with an attribute of
EFI_OPEN_PROTOCOL_BY_DRIVER and so we cannot maintain a safe,
long-lived pointer to the device path. Work around this by instead
opening the device path protocol with an attribute of
EFI_OPEN_PROTOCOL_GET_PROTOCOL whenever we need to use it.
Debugged-by: Curtis Larsen <larsen@dixie.edu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
efi_file_install() and efi_download_install() are both used to install
onto existing handles. There is therefore no need to allow for each
of their calls to InstallMultipleProtocolInterfaces() to create a new
handle.
By passing the handle directly (rather than a pointer to the handle),
we avoid potential confusion (and erroneous debug message colours).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The EFI headers define EFI_HANDLE as a void pointer, which renders
type checking on anything dealing with EFI handles somewhat useless.
Work around this bizarre sabotage attempt by redefining EFI_HANDLE as
a pointer to an anonymous structure.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a function efi_handle_name() (as a generalisation of
efi_handle_devpath_text()) which tries various methods to produce a
human-readable name for an EFI handle.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Reject network devices which appear to be duplicates of those already
available via a different underlying hardware device. On a Xen PV-HVM
system, this allows us to filter out the emulated PCI NICs (which
would otherwise appear alongside the netfront NICs).
Note that we cannot use the Xen facility to "unplug" the emulated PCI
NICs, since there is no guarantee that the OS we subsequently load
will have a native netfront driver.
We permit devices with the same MAC address if they are attached to
the same underlying hardware device (e.g. VLAN devices).
Inspired-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We currently treat network devices as available for use via the SNP
API only if RX queue processing has been frozen. (This is similar in
spirit to the way that RX queue processing is frozen for the network
device currently exposed via the PXE API.)
The default state of a freshly created network device is for the RX
queue to not be frozen, and thus to be unavailable for use via SNP.
This causes problems when devices are added through code paths other
than _efidrv_start() (which explicitly releases devices for use via
SNP).
We don't actually need to freeze RX queue processing, since calls via
the SNP API will always use netdev_poll() rather than net_poll(), and
so will never trigger the RX queue processing code path anyway.
We can therefore simplify the code to use a single global flag to
indicate whether network devices are claimed for use by iPXE or
available for use via SNP. Using a global flag allows the default
state for dynamically created network devices to behave sensibly.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add basic support for Xen PV-HVM domains (detected via the Xen
platform PCI device with IDs 5853:0001), including support for
accessing configuration via XenStore and enumerating devices via
XenBus.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Import selected headers from the xen/include/public directory of the
Xen repository at git://xenbits.xen.org/xen.git
The script ./include/xen/import.pl can be used to automatically import
any required headers and their dependencies (in a similar fashion to
./include/ipxe/efi/import.pl). Trailing whitespace is stripped and an
appropriate FILE_LICENCE declaration is added to each header file.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The EFI_CONSOLE_CONTROL_PROTOCOL does not exist in the current UEFI
specification, but is required to enable text output on some older EFI
1.10 implementations (observed on an old iMac).
The header is not present in any of the standard include directories,
but can still be found in the EDK2 codebase as part of
EdkCompatibilityPkg.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When building with DEBUG=efi_wrap, print details of calls made by the
loaded image to selected boot services functions.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The EFI FAT filesystem driver has a bug: if a block device contains no
FAT filesystem but does have an EFI_SIMPLE_FILE_SYSTEM_PROTOCOL
instance, the FAT driver will assume that it must have previously
installed the EFI_SIMPLE_FILE_SYSTEM_PROTOCOL. This causes the FAT
driver to claim control of our device, and to refuse to stop driving
it, which prevents us from later uninstalling correctly.
Work around this bug by opening the disk I/O protocol ourselves,
thereby preventing the FAT driver from opening it.
Note that the alternative approach of opening the block I/O protocol
(and thereby in theory preventing DiskIo from attaching to the block
I/O protocol) causes an endless loop of calls to our DRIVER_STOP
method when starting the EFI shell. I have no idea why this is.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a single instance of EFI_DRIVER_BINDING_PROTOCOL (attached to
our image handle); this matches the expectations scattered throughout
the EFI specification.
Open the underlying hardware device using EFI_OPEN_PROTOCOL_BY_DRIVER
and EFI_OPEN_PROTOCOL_EXCLUSIVE, to prevent other drivers from
attaching to the same device.
Do not automatically connect to devices when being loaded as a driver;
leave this task to the platform firmware (or to the user, if loading
directly from the EFI shell).
When running as an application, forcibly disconnect any existing
drivers from devices that we want to control, and reconnect them on
exit.
Provide a meaningful driver version number (based on the build
timestamp), to allow platform firmware to automatically load newer
versions of iPXE drivers if multiple drivers are present.
Include device paths within debug messages where possible, to aid in
debugging.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Expose the build timestamp (measured in seconds since the Epoch) and
the build name (e.g. "rtl8139.rom" or "ipxe.efi"), and provide the
product name and product short name in a single centralised location.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
With blade servers, the chassis serial number (exposed via ${serial})
may not be unique. Expose ${board-serial} as a named setting to
provide easy access to a more meaningful serial number.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The iBFT includes an "origin" field to indicate the source of the IP
address. We use the heuristic of assuming that the source should be
"manual" if the IP address originates directly from the network device
settings block, and "DHCP" otherwise. This is an imperfect guess, but
is likely to be correct in most common situations.
Originally-implemented-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Parse the sense data to extract the reponse code, the sense key, the
additional sense code, and the additional sense code qualifier.
Originally-implemented-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Fix an erroneous htonl() in the definition of IN6_IS_ADDR_LINKLOCAL(),
and add self-tests for the IN6_IS_ADDR_xxx() family of macros.
Reported-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Get the NFS URI manipulation code out of nfs_open.c. The resulting
code is now much more readable.
Signed-off-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Interrupt processing adds noise to profiling results. Allow
interrupts (from within protected mode) to be profiled separately,
with time spent within the interrupt handler being excluded from any
other profiling currently in progress.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for an explicit debug level of zero, which will enable
assertions and profiling (i.e. anything controlled by NDEBUG) without
generating any debug messages.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Expand the concept of the X.509 cache to provide the functionality of
a certificate store. Certificates in the store will be automatically
used to complete certificate chains where applicable.
The certificate store may be prepopulated at build time using the
CERT=... build command line option. For example:
make bin/ipxe.usb CERT=mycert1.crt,mycert2.crt
Certificates within the certificate store are not implicitly trusted;
the trust list is specified using TRUST=... as before. For example:
make bin/ipxe.usb CERT=root.crt TRUST=root.crt
This can be used to embed the full trusted root certificate within the
iPXE binary, which is potentially useful in an HTTPS-only environment
in which there is no HTTP server from which to automatically download
cross-signed certificates or other certificate chain fragments.
This usage of CERT= extends the existing use of CERT= to specify the
client certificate. The client certificate is now identified
automatically by checking for a match against the private key. For
example:
make bin/ipxe.usb CERT=root.crt,client.crt TRUST=root.crt KEY=client.key
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE currently allocates a copy the certificate's common name as a
string. This string is used by the TLS and CMS code to check
certificate names against an expected name, and also appears in
debugging messages.
Provide a function x509_check_name() to centralise certificate name
checking (in preparation for adding subjectAlternativeName support),
and a function x509_name() to provide a name to be used in debugging
messages, and remove the dynamically allocated string.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some UEFI builds will set up a timer to continuously poll any SNP
devices. This can drain packets from the network device's receive
queue before iPXE gets a chance to process them.
Use netdev_rx_[un]freeze() to explicitly indicate when we expect our
network devices to be driven via the external SNP API (as we do with
the UNDI API on the standard BIOS build), and disable the SNP API
except when receive queue processing is frozen.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
On a 64-bit build, EFI_STATUS codes are 64-bit quantities, with the
"error/warning" bit located in bit 63.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE will detect timeout failures in several situations: network
link-up, DHCP, TCP connection attempts, unacknowledged TCP data, etc.
This does not cover all possible circumstances. For example, if a
connection to a web server is successfully established and the web
server acknowledges the HTTP request but never sends any data in
response, then no timeout will be triggered. There is no timeout
defined within the HTTP specifications, and the underlying TCP
connection will not generate a timeout since it has no way to know
that the HTTP layer is expecting to receive data from the server.
Add a "--timeout" parameter to "imgfetch", "chain", etc. If no
progress is made (i.e. no data is downloaded) within the timeout
period, then the download will be aborted.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE currently advertises a fixed MSS of 1460, which is correct only
for IPv4 over Ethernet. For IPv6 over Ethernet, the value should be
1440 (allowing for the larger IPv6 header). For non-Ethernet link
layers, the value should reflect the MTU of the underlying network
device.
Use tcpip_mtu() to calculate the transport-layer MTU associated with
the peer address, and calculate the MSS to allow for an optionless TCP
header as per RFC 6691.
As a side benefit, we can now fail a connection immediately with a
meaningful error message if we have no route to the destination
address.
Reported-by: Anton D. Kachalov <mouse@yandex-team.ru>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide the function tcpip_mtu() to allow external code to determine
the (transport-layer) maximum transmission unit for a given socket
address.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide the function tcpip_netdev() to allow external code to
determine the transmitting network device for a given socket address.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE will currently attempt to boot from every network device for
which it has a driver. Where a system has more than one network
device supported by iPXE, this renders BIOS IPL lists ineffective.
Allow an autoboot device location to be specified. If such a location
is specified, then only devices matching that location will be used as
part of the automatic boot sequence. If no such location is
specified, then all devices will be used.
Note that this does not affect the "autoboot" command, which will
continue to use all devices.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add support for parsing of URIs containing literal IPv6 addresses
(e.g. "http://[fe80::69ff:fe50:5845%25net0]/boot.ipxe").
Duplicate URIs by directly copying the relevant fields, rather than by
formatting and reparsing a URI string. This relaxes the requirements
on the URI formatting code and allows it to focus on generating
human-readable URIs (e.g. by not escaping ':' characters within
literal IPv6 addresses). As a side-effect, this allows relative URIs
containing parameter lists (e.g. "../boot.php##params") to function
as expected.
Add validity check for FTP paths to ensure that only printable
characters are accepted (since FTP is a human-readable line-based
protocol with no support for character escaping).
Construct TFTP next-server+filename URIs directly, rather than parsing
a constructed "tftp://..." string,
Add self-tests for URI functions.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Update the DNS resolver to support DNS search lists (as provided by
DHCP option 119, DHCPv6 option 24, or NDP option 31).
Add validation code to ensure that parsing of DNS packets does not
overrun the input, get stuck in infinite loops, or (worse) write
beyond the end of allocated buffers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Rename the "--bpp" option to "--depth", to free up the single-letter
option "-b" for "--bottom" in preparation for adding margin support.
This does not break backwards compatibility with documented features,
since the "console" command has not yet been documented.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Centre the background picture on the console, to give a more
consistent result when the aspect ratio does not match the requested
width and height.
Once drawn for the first time, nothing should ever overwrite the
margins of the display. We can therefore eliminate the logic used to
redraw only the margin areas, and use much simpler code to draw the
complete initial background image.
Simplify the redrawing logic further by making the background picture
buffer equal in size to the frame buffer. In the common case of a
background picture which is designed to fill the screen, this wastes
no extra memory, and the combined code simplifications reduce the size
of fbcon.o by approximately 15%.
Redefine the concept of "margin" to match the intuitive definition
(i.e. the size of the gap, rather than the position of the boundary
line).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow test reports to specify an explicit file name and line number
using the extended okx() macro. This allows large blocks of test
report code such as tcpip_random_ok() to be implemented as functions
rather than macros.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The magic basic colour can be remapped at runtime from COLOR_NORMAL_BG
(usually blue) to COLOR_DEFAULT (which will be transparent as a
background colour on the framebuffer console).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add a centralised concept of colours and colour pairs (using the
default colour pairs as configured via config/colour.h). A colour
pair consists of a pair of colour indices.
Add the ability to redefine both a colour pair and an individual
colour index, with minimal overhead if this feature is not required
(e.g. because the relevant shell commands are not present in the
build).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a mechanism for consoles to update the recorded console width
and height, and use this width and height to provide the curses COLS
and LINES variables.
We choose not to use ANSI escape sequences to obtain the width and
height, for two reasons:
- iPXE's model is that all output is sent to all consoles; we could
therefore end up with multiple consoles reporting conflicting widths
and heights
- when a serial console is in use, we probably don't want to resize
the output shown on the BIOS console to match the size of the serial
console, since it's likely that the serial console is in use only
for debugging.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for equivalent IPv4 and IPv6 settings (which requires equivalent
settings to be adjacent within the settings list).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Note that IANA has not yet assigned a DHCPv6 option code for the
syslog server. When a code is assigned, the definition of
DHCPV6_LOG_SERVERS should be updated. Until then, an IPv6 address of
a syslog server can be configured manually using e.g.
set syslog6 3ffe:302:11:2::8309
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Our policy is to prefer IPv6 addreses to IPv4 addresses, but to
request IPv6 addresses only if we have an IPv6 address for the name
server itself.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for the existence of references to IPv6 setting types without
dragging in the whole IPv6 stack, by placing the definition of
setting_type_ipv6 in core/settings.c and providing weak stub methods
for parse_ipv6_setting() and format_ipv6_setting().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The fetch_setting() family of functions may currently modify the
definition of the specified setting (e.g. to add missing type
information). Clean up this interface by requiring callers to provide
an explicit buffer to contain the completed definition of the fetched
setting, if required.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The ANSI escape sequences to show and hide the cursor take the form
"<ESC>[?25h" and "<ESC>[?25l" respectively. iPXE currently treats the
'?' character as the final byte. Fix by explicitly treating '?' as an
intermediate byte.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow for IPv6 routing table entries to be created for an on-link
prefix where a local address has not yet been assigned to the network
device.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add support for the stateful and stateless variants of the DHCPv6
protocol. The resulting settings block is registered as
"net<x>.dhcpv6", and DHCPv6 options can be obtained using
e.g. "${net0.dhcpv6/23:ipv6}" to obtain the IPv6 DNS server address.
IPv6 addresses obtained via stateful DHCPv6 are not yet applied to the
network device.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Include IPv6 within the generic network device configurator
mechanism. The IPv6 configurator will send a router solicitation and
wait for a router advertisement to be received. (As per RFC4861
section 6.3.7, we do this even if advertisements have been received
prior to sending the router solicitation.)
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE supports multiple mechanisms for network device configuration:
DHCPv4 for IPv4, FIP for FCoE, and SLAAC for IPv6. At present, DHCPv4
requires an explicit action (e.g. a "dhcp" command), FIP is initiated
implicitly upon opening a network device, and SLAAC takes place
whenever a RA happens to be received.
Add a generic concept of a network device configurator, which provides
a common interface to triggering configuration and to reporting the
result of the configuration process.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some background jobs have a meaningful ongoing status code (e.g. the
current link status for a job waiting for a network link to come up).
Allow this to be exposed via the job_progress() method.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Parsing a timeout value (specified in milliseconds) into an internal
timeout value measured in timer ticks is a common operation. Provide
a parse_timeout() value to carry out this conversion automatically.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When chainloading, always retrieve the cached DHCPACK packet from the
underlying PXE stack, and apply it as the original contents of the
"net<X>.dhcp" settings block. This allows cached DHCP settings to be
used for any chainloaded iPXE binary (not just undionly.kkpxe).
This change eliminates the undocumented "use-cached" setting. Issuing
the "dhcp" command will now always result in a fresh DHCP request.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add generic pinger mechanism (analogous to the generic downloader
mechanism) which opens a ping socket, transmits ping requests, and
passes information about ping replies to a callback function.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Merge common functionality between IPv4 and IPv6 ICMP echo handling,
and add support for transmitting ICMP echo requests and delivering
ICMP echo replies to a (not yet implemented) ping_rx() function.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The path MTU is currently hardcoded to 1460 bytes, which fails to
allow space for TCP options. Sending a maximum-sized datagram (which
is viable when using HTTP POST) will therefore fail since the Ethernet
MTU will be exceeded.
Reduce the hardcoded path MTU to produce a maximum datagram of 1280
bytes, which is the size required of data link layers by IPv6. It is
a reasonable assumption that all intermediary data link layers will be
able to convey this packet without fragmentation, even for IPv4.
Note that this reduction has a minimal impact upon download
throughput, since it affects only the transmit data path.
Originally-fixed-by: Suresh Sundriyal <ssundriy@vmware.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Replace the existing partially-implemented IPv6 stack with a fresh
implementation.
This implementation is not yet complete. The IPv6 transmit and
receive datapaths are functional (including fragment reassembly and
parsing of arbitrary extension headers). NDP neighbour solicitations
and advertisements are supported. ICMPv6 echo is supported.
At present, only link-local addresses may be used, and there is no way
to specify an IPv6 address as part of a URI (either directly or via
a DNS lookup).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Split the protocol-independent portions of arp.c into a separate file
neighbour.c, to allow for sharing of functionality between IPv4+ARP
and IPv6+NDP.
Signed-off-by: Michael Brown <mcb30@ipxe.org>