UEFI UNDI is a hideously ugly lump of poorly specified garbage bolted
on as an appendix of the UEFI specification. My personal favourite
line from the UNDI 'specification' is section E.2.2, which states
"Basically, the rule is: Do it right, or don't do it at all". The
author appears to believe that such exhortations are a viable
substitute for documenting what it is that the wretched reader is
supposed to, in fact, do.
(Second favourite is the section listing the pros and cons of various
driver types. This fails to identify a single con for the mythical
"Hardware UNDI", a design so insanely intrinsically slow that it
appears to have been the inspiration for the EFI_USB_IO_PROTOCOL.)
UNDI is functionally isomorphic to the substantially less preposterous
EFI_SIMPLE_NETWORK_PROTOCOL. Provide an UNDI interface (as a thin
wrapper around the existing SNP interface) to allow for use by
third-party software that has made poor life choices.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Calling EDK2's OpenProtocol() with attributes BY_DRIVER|EXCLUSIVE will
call DisconnectController() in a loop to attempt to dislodge any
existing openers with attributes BY_DRIVER. The loop will continue
indefinitely until either no such openers remain, or until
DisconnectController() returns an error.
If our driver binding protocol's Stop() method is ever called to
disconnect a device that we are not in fact driving, then return
EFI_DEVICE_ERROR rather than EFI_SUCCESS, in order to break this
potentially infinite loop.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow the UEFI platform firmware to provide drivers for unrecognised
devices, by exposing our own implementation of EFI_USB_IO_PROTOCOL.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Many UEFI NBPs expect to find an EFI_PXE_BASE_CODE_PROTOCOL installed
in addition to the EFI_SIMPLE_NETWORK_PROTOCOL. Most NBPs use the
EFI_PXE_BASE_CODE_PROTOCOL only to retrieve the cached DHCP packets.
This implementation has been tested with grub.efi, shim.efi,
syslinux.efi, and wdsmgfw.efi. Some methods (such as Discover() and
Arp()) are not used by any known NBP and so have not (yet) been
implemented.
Usage notes for the tested bootstraps are:
- grub.efi uses EFI_PXE_BASE_CODE_PROTOCOL only to retrieve the
cached DHCP packet, and uses no other methods.
- shim.efi uses EFI_PXE_BASE_CODE_PROTOCOL to retrieve the cached
DHCP packet and to retrieve the next NBP via the Mtftp() method.
If shim.efi was downloaded via HTTP (or other non-TFTP protocol)
then shim.efi will blindly call Mtftp() with an HTTP URI as the
filename: this allows the next NBP (e.g. grubx64.efi) to also be
transparently retrieved by HTTP.
shim.efi can also use the EFI_SIMPLE_FILE_SYSTEM_PROTOCOL to
retrieve files previously loaded by "imgfetch" or similar commands
in iPXE. The current implementation of shim.efi will use the
EFI_SIMPLE_FILE_SYSTEM_PROTOCOL only if it does not find an
EFI_PXE_BASE_CODE_PROTOCOL; this patch therefore prevents this
usage of our EFI_SIMPLE_FILE_SYSTEM_PROTOCOL. This logic could be
trivially reversed in shim.efi if needed.
- syslinux.efi uses EFI_PXE_BASE_CODE_PROTOCOL only to retrieve the
cached DHCP packet. Versions 6.03 and earlier have a bug which
may cause syslinux.efi to attach to the wrong NIC if there are
multiple NICs in the system (or if the UEFI firmware supports
IPv6).
- wdsmgfw.efi (ab)uses EFI_PXE_BASE_CODE_PROTOCOL to retrieve the
cached DHCP packets, and to send and retrieve UDP packets via the
UdpWrite() and UdpRead() methods. (This was presumably done in
order to minimise the amount of benefit obtainable by switching to
UEFI, by replicating all of the design mistakes present in the
original PXE specification.)
The EFI_DOWNGRADE_UX configuration option remains available for now,
until this implementation has received more widespread testing.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Our SNP ReceiveFilters() method is a no-op, since we always (if
possible) use promiscuous mode for all network cards. The method
currently returns EFI_NOT_READY if the SNP interfaces are claimed for
use by iPXE, as with all other SNP methods.
The WDS bootstrap wdsmgfw.efi attempts to use both the PXE Base Code
protocol and the Simple Network Protocol simultaneously. This is
fundamentally broken, since use of the PXE Base Code protocol requires
us to disable the use of SNP (by claiming the interfaces for use by
iPXE), otherwise MnpDxe swallows all of the received packets before
our PXE Base Code's UdpRead() method is able to return them.
The root cause of this problem is that, as with BIOS PXE, the network
booting portions of the UEFI specification are less of a specification
and more of an application note sketchily describing how the original
hacked-together Intel implementation works. No sane design would ever
have included the UdpWrite() and UdpRead() methods.
Work around these fundamental conceptual flaws by unconditionally
returning success from efi_snp_receive_filters().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add definitions of protocols observed to be used by wdsmgfw.efi, and
add a handle name type for ConIn, ConOut, and StdErr.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add debug wrappers for more boot services functions, and print
symbolic values rather than raw numbers where possible.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The raw EFI_HANDLE value is almost never useful to know, and simply
adds noise to the already verbose debug messages. Improve the
legibility of debug messages by using only the name generated by
efi_handle_name().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow the return status from an embedded image to propagate out to the
eventual return status from main(). When running under Linux, this
allows the pass/fail result of unit tests to be observable without
having to visually inspect the console output.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
UEFI platforms may provide a watchdog timer, which will reboot the
machine if an operating system takes more than five minutes to load.
This can cause long-lived iPXE downloads (or interactive shell
sessions) to unexpectedly reboot.
Fix by resetting the watchdog timer every ten seconds while the iPXE
main processing loop continues to run.
Reported-by: Bradley B Williams <bradleybwilliams@swbell.net>
Reported-by: John Clark <john.r.clark.3@gmail.com>
Reported-by: wdriever@gmail.com
Reported-by: Charlie Beima <cbeima@indiana.edu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
iPXE does not currently provide EFI_PXE_BASE_CODE_PROTOCOL: this
causes failures when chainloading bootloaders such as shim.efi which
assume that this protocol will be present.
Provide the ability to work around these problems via the build
configuration option EFI_DOWNGRADE_UX. If this option is enabled,
then we will not install our usual EFI_LOAD_FILE_PROTOCOL
implementation, thereby allowing the platform firmware to install its
own EFI_PXE_BASE_CODE_PROTOCOL implementation on top of our
EFI_SIMPLE_NETWORK_PROTOCOL handle.
A somewhat major side-effect of this workaround is that almost all
iPXE features will be disabled.
This configuration option will be removed in future when support for
EFI_PXE_BASE_CODE_PROTOCOL is added.
Requested-by: Laszlo Ersek <lersek@redhat.com>
Requested-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Fix the TxBuf value filled in by GetStatus() to report the transmit
buffer address as required by the (now clarified) specification.
Simplify "interrupt" handling in GetStatus() to report only that one
or more packets have been transmitted or received; there is no need to
report one GetStatus() "interrupt" per packet.
Simplify receive handling to dequeue received packets immediately from
the network device into an internal list (thereby avoiding the hacks
previously used to determine when to report new packet arrivals).
Originally-fixed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Older, out-of-tree Xen kernel modules (such as those provided with
SuSE Linux Enterprise Server 11) do not clear the leftover "event
pending" bit when opening an event channel. Consequently, no event is
ever delivered to indicate that there is information in the XenStore
ring buffer, and the system hangs shortly after loading the
xen-platform-pci kernel module.
Work around this problem by always waiting for the XenStore event
channel to be signalled, and clearing the event before processing the
received data.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The current API for Base16 (and Base64) encoding requires the caller
to always provide sufficient buffer space. This prevents the use of
the generic encoding/decoding functionality in some situations, such
as in formatting the hex setting types.
Implement a generic hex_encode() (based on the existing
format_hex_setting()), implement base16_encode() and base16_decode()
in terms of the more generic hex_encode() and hex_decode(), and update
all callers to provide the additional buffer length parameter.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Rewrite (and relicense) the header files which are included in all
builds of iPXE (including non-Linux builds).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
These files cannot be automatically relicensed by util/relicense.pl
since they either contain unusual but trivial contributions (such as
the addition of __nonnull function attributes), or contain lines
dating back to the initial git revision (and so require manual
knowledge of the code's origin).
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Relicence files with kind permission from the following contributors:
Alex Williamson <alex.williamson@redhat.com>
Eduardo Habkost <ehabkost@redhat.com>
Greg Jednaszewski <jednaszewski@gmail.com>
H. Peter Anvin <hpa@zytor.com>
Marin Hannache <git@mareo.fr>
Robin Smidsrød <robin@smidsrod.no>
Shao Miller <sha0.miller@gmail.com>
Thomas Horsten <thomas@horsten.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
We require the ability to disconnect from and reconnect to VMBus; if
we don't have this then there is no (viable) way for a loaded
operating system to continue to use any VMBus devices. (There is also
a small but non-zero risk that the host will continue to write to our
interrupt and monitor pages, since the VMBUS_UNLOAD message in earlier
versions is essentially a no-op.)
This requires us to ensure that the host supports protocol version 3.0
(VMBUS_VERSION_WIN8_1). However, we can't actually _use_ protocol
version 3.0, since doing so causes an iSCSI-booted Windows Server 2012
R2 VM to crash due to a NULL pointer dereference in vmbus.sys.
To work around this problem, we first ensure that we can connect using
protocol v3.0, then disconnect and reconnect using the oldest known
protocol.
This deliberately prevents the use of the iPXE native Hyper-V drivers
on older versions of Hyper-V, where we could use our drivers but in so
doing would break the loaded operating system.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The (undocumented) VMBus protocol seems to allow for transfer
page-based packets where the data payload is split into an arbitrary
set of ranges within the transfer page set.
The RNDIS protocol includes a length field within the header of each
message, and it is known from observation that multiple RNDIS messages
can be concatenated into a single VMBus message.
iPXE currently assumes that the transfer page range boundaries are
entirely arbitrary, and uses the RNDIS header length to determine the
RNDIS message boundaries.
Windows Server 2012 R2 generates an RNDIS_INDICATE_STATUS_MSG for an
undocumented and unknown status code (0x40020006) with a malformed
RNDIS header length: the length does not cover the StatusBuffer
portion of the message. This causes iPXE to report a malformed RNDIS
message and to discard any further RNDIS messages within the same
VMBus message.
The Linux Hyper-V driver assumes that the transfer page range
boundaries correspond to RNDIS message boundaries, and so does not
notice the malformed length field in the RNDIS header.
Match the behaviour of the Linux Hyper-V driver: assume that the
transfer page range boundaries correspond to the RNDIS message
boundaries and ignore the RNDIS header length. This avoids triggering
the "malformed packet" error and also avoids unnecessary data copying:
since we now have one I/O buffer per RNDIS message, there is no longer
any need to use iob_split().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some UEFI systems (observed with a Hyper-V virtual machine) do not
provide EFI_PCI_ROOT_BRIDGE_IO_PROTOCOL. Make this an optional
protocol (and fail any attempts to access PCI configuration space via
the root bridge if the protocol is missing).
Reported-by: Colin Blacker <Colin.Blacker@computerplanet.co.uk>
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>
Michael Brown