[comboot] Allow for tail recursion of COMBOOT images
Multi-level menus via COMBOOT rely on the COMBOOT program being able
to exit and invoke a new COMBOOT program (the next menu). This works,
but rapidly (within about five iterations) runs out of space in gPXE's
internal stack, since each new image is executed in a new function
context.
Fix by allowing tail recursion between images; an image can now
specify a replacement image for itself, and image_exec() will perform
the necessary tail recursion.
[build] Cope with oddities in the Fedora 10 assembler
The version of the GNU assembler shipped with Fedora 10
(2.18.50.0.9-8.fc10) complains about character literals in some of our
assembly code. Changing $'x' to $( 'x' ) seems to fix the problem.
Yes, the whitespace is required; using just $('x') does not work.
Reported by Kevin O'Connor <kevin@koconnor.net>.
This patch extends the embedded image feature to allow multiple
embedded images instead of just one.
gPXE now always boots the first embedded image on startup instead of
doing the hardcoded DHCP boot (aka autoboot).
Based heavily upon a patch by Stefan Hajnoczi <stefanha@gmail.com>.
[romprefix] Update ROM checksum even if PMM allocation fails
There are code paths other than PMM allocation that can result in our
changing the ROM checksum. For example, we attempt to update our
product string to incorporate the PCI bus:dev.fn number. In a system
that does not support PMM, we could therefore end up with an incorrect
checksum.
Fix by attempting to update the checksum unconditionally.
[i386] Add explicit ""aw", @nobits" declarations to stack sections
As reported by Stefan, commit 13d09e6 ("[i386] Simplify linker script
and standardise linker-defined symbol names") breaks gdb, readelf and
associated utilities.
This is caused by the .stack section overwriting a block in the middle
of the .debug_info section (despite being included in the
.bss.textdata section in the output file, which apparently has the
correct attributes for a .bss section).
Fixed by adding explicit flags and type to the stack section
declaration.
[xfer] Make consistent assumptions that xfer metadata can never be NULL
The documentation in xfer.h and xfer.c does not say that the metadata
parameter is optional in calls such as xfer_deliver_iob_meta() and the
deliver_iob() method. However, some code in net/ is prepared to
accept a NULL pointer, and xfer_deliver_as_iob() passes a NULL pointer
directly to the deliver_iob() method.
Fix this mess of conflicting assumptions by making everything assume
that the metadata parameter is mandatory, and fixing
xfer_deliver_as_iob() to pass in a dummy metadata structure (as is
already done in xfer_deliver_iob()).
[umalloc] Avoid problems when _textdata_memsz is a multiple of 4kB
If it happens that _textdata_memsz ends up being an exact multiple of
4kB, then this will cause the .textdata section (after relocation) to
start on a page boundary. This means that the hidden memory region
(which is rounded down to the nearest page boundary) will start
exactly at virtual address 0, i.e. UNULL. This means that
init_eheap() will erroneously assume that it has failed to allocate a
an external heap, since it typically ends up choosing the area that
lies immediately below .textdata, which in this case will be the
region with top==UNULL.
A subsequent error is that memtop_urealloc() passes through the error
return status -ENOMEM to the caller, which (rightly) assumes that the
result represents a valid userptr_t address.
Fixed by using alternative tests for heap non-existence, and by
returning UNULL in case of an error from init_eheap().
fetchf_uristring() was failing to handle error values from
fetch_setting(), resulting in its attempting to allocate extremely
large temporary buffers on the stack (and so overrunning the stack and
locking up the machine).
Problem reported by Shao Miller <Shao.Miller@yrdsb.edu.on.ca>.
This previously unsupported NIC variant was was found to work using
the current driver:
PCI_ROM(0x13f0, 0x0200, "ip100a", "IC+ IP100A"),
Signed-off-by: Marty Connor <mdc@etherboot.org>
[pxe] Display the "Press F8" prompt rather than displaying menu with timeout
The PXE spec dictates the rather ugly feature that we have to present
a DHCP-specified prompt string to the user, then wait to see if they
press F8 before displaying the menu.
This seems to me to be a significant retrograde step from the current
situation of displaying the menu with the timeout counting down
against the default selected boot option, but apparently the lack of
the "Press F8" prompt causes some confusion.
[pxe] Obey lists of PXE Boot Servers and associated Discovery Control bits
Various combinations of options 43.6, 43.7 and 43.8 dictate which
servers we send Boot Server Discovery requests to, and which servers
we should accept responses from. Obey these options, and remove the
explicit specification of a single Boot Server from start_pxebs() and
dependent functions.
[iobuf] Add iob_disown() and use it where it simplifies code
There are many functions that take ownership of the I/O buffer they
are passed as a parameter. The caller should not retain a pointer to
the I/O buffer. Use iob_disown() to automatically nullify the
caller's pointer, e.g.:
xfer_deliver_iob ( xfer, iob_disown ( iobuf ) );
This will ensure that iobuf is set to NULL for any code after the call
to xfer_deliver_iob().
iob_disown() is currently used only in places where it simplifies the
code, by avoiding an extra line explicitly setting the I/O buffer
pointer to NULL. It should ideally be used with each call to any
function that takes ownership of an I/O buffer. (The SSA
optimisations will ensure that use of iob_disown() gets optimised away
in cases where the caller makes no further use of the I/O buffer
pointer anyway.)
If gcc ever introduces an __attribute__((free)), indicating that use
of a function argument after a function call should generate a
warning, then we should use this to identify all applicable function
call sites, and add iob_disown() as necessary.
A TFTP DATA packet with a block number of zero (representing a
negative offset within the file) could potentially cause problems.
Fixed by explicitly rejecting such packets.
Identified by Stefan Hajnoczi <stefanha@gmail.com>.
The DHCP client code now implements only the mechanism of the DHCP and
PXE Boot Server protocols. Boot Server Discovery can be initiated
manually using the "pxebs" command. The menuing code is separated out
into a user-level function on a par with boot_root_path(), and is
entered in preference to a normal filename boot if the DHCP vendor
class is "PXEClient" and the PXE boot menu option exists.
Automatically unregister any settings with the same name (and position
within the settings tree) as a newly registered settings block.
This functionality is generalised out from dhcp.c.
[scsi] Cope with targets that send multiple CHECK CONDITIONS at power-on
Some targets send a spurious CHECK CONDITION message in response to
the first SCSI command. We issue (and ignore the status of) an
arbitary harmless SCSI command (a READ CAPACITY (10)) in order to draw
out this response.
The Solaris Comstar target seems to send more than one spurious CHECK
CONDITION response. Attempt up to SCSI_MAX_DUMMY_READ_CAP dummy READ
CAPACITY (10) commands before assuming that error responses are
meaningful.
Problem reported by Kristof Van Doorsselaere <kvandoor@aserver.com>
and Shiva Shankar <802.11e@gmail.com>.
Try to qualify relative names in the DNS resolver using the DHCP Domain
Name. For example:
DHCP Domain Name: etherboot.org
(Relative) Name: www
yields:
www.etherboot.org
Only names with no dots ('.') will be modified. A name with one or more
dots is unchanged.
[tftp] Temporary fix for conveying TFTP block size to callers
pxe_tftp.c assumes that the first seek on its data-transfer interface
represents the block size. Apart from being an ugly hack, this will
also screw up file size calculation for files smaller than one block.
The proper solution would be to extend the data-transfer interface to
support the reporting of stat()-like data. This is not going to
happen until the cost of adding interface methods is reduced (a fix I
have planned since June 2008).
In the meantime, abuse the xfer_window() method to return the block
size, since it is not being used for anything else and is vaguely
justifiable.
Astonishingly, having returned the incorrect TFTP blocksize via
PXENV_TFTP_OPEN for almost a year seems not to have affected any of
the test cases run during that time; this bug was found only when
someone tried running the heavily-patched version of pxegrub found in
OpenSolaris.
PXE dictates a mechanism for boot menuing, involving prompting the
user with a variable message, waiting for a predefined keypress,
displaying a boot menu, and waiting for a selection.
This breaks the currently desirable abstraction that DHCP is a process
that can happen in the background without any user interaction.
[console] Allow KEY_xxx constants to cover F8 function key
F8 is represented by the ANSI escape sequence "^[[19~", which is not
representable as a KEY_xxx constant using the current encoding scheme.
Adapt the encoding scheme to allow F8 to be represented, since PXE
requires that we may need to prompt the user to press F8.
Remove the lazy assumption that ProxyDHCP == "DHCP with option 60 set
to PXEClient", and explicitly separate the notion of ProxyDHCP from
the notion of packets containing PXE options.
It is possible to configure a DHCP server to hand out PXE options
without a ProxyDHCP server present. This requires setting option 60
to "PXEClient", which will cause gPXE to attempt ProxyDHCP.
We assume in several places that dhcp->proxydhcpack is set to the
DHCPACK packet containing option 60 set to "PXEClient". When we
transition into ProxyDHCPREQUEST, set dhcp->proxydhcpack=dhcp->dhcpack
so that this assumption holds true.
We ought to rename several references to "proxydhcp" to something more
accurate, such as "pxedhcp". Treating a single DHCP response as
potentially both DHCPOFFER and ProxyDHCPOFFER does make the code
smaller, but the variable names get confusing.
Pick out the first boot menu item from the boot menu (option 43.9) and
pass it to the boot server as the boot menu item (option 43.71).
Also improve DHCP debug messages to include more details of the
packets being transmitted.
Apparently this can cause a major speedup on some iSCSI targets, which
will otherwise wait for a timer to expire before responding. It
doesn't seem to hurt other simple TCP test cases (e.g. HTTP
downloads).
Problem and solution identified by Shiva Shankar <802.11e@gmail.com>
[dhcp] Add preliminary support for PXE Boot Servers
Some PXE configurations require us to perform a third DHCP transaction
(in addition to the real DHCP transaction and the ProxyDHCP
transaction) in order to retrieve information from a "Boot Server".
This is an experimental implementation, since the actual behaviour is
not well specified in the PXE spec.
[tcpip] Allow for transmission to multicast IPv4 addresses
When sending to a multicast address, it may be necessary to specify
the source address explicitly, since the multicast destination address
does not provide enough information to deduce the source address via
the miniroute table.
Allow the source address specified via the data-xfer metadata to be
passed down through the TCP/IP stack to the IPv4 layer, which can use
it as a default source address.
[dhcp] Centralise DHCP successful state transitions
Move all the DHCP state transition logic into a single function
dhcp_next_state(). This will make it easier to add support for PXE
Boot Servers, since it abstracts away the difference between "mark
DHCP as complete" and "transition to boot server discovery".
[dhcp] Allow for missing server ID in ProxyDHCPACK
The Linux PXE server (http://www.kano.org.uk/projects/pxe) does not
set the server identifier in its ProxyDHCP responses. If the server
ID is missing, do not treat this as an error.
This resolves the "vague and unsettling memory" mentioned in commit
fdb8481d ("[dhcp] Verify server identifier on ProxyDHCPACKs").
Note that we already accept ProxyDHCPOFFERs without a server
identifier; they get treated as potential BOOTP packets.
[efi] Expose both GUIDs for the EFI_NETWORK_INTERFACE_IDENTIFIER_PROTOCOL
At some point, it seems that someone decided to change the GUID for
the EFI_NETWORK_INTERFACE_IDENTIFIER_PROTOCOL. Current EFI builds
ignore the older GUID, older EFI builds ignore the newer GUID, so we
have to expose both.
[efi] Provide component name protocol and device path protocol interfaces
Include a minimal component name protocol so that the driver name
shows up as something other than "<UNKNOWN>" in the driver list, and a
device path protocol so that the network interface shows up as a
separate device in the device list, rather than being attached
directly to the PCI device.
Incidentally, the EFI component name protocol reaches new depths for
signal-to-noise ratio in program code. A typical instance within the
EFI development kit will use an additional 300 lines of code to
provide slightly less functionality than GNU gettext achieves with
three additional characters.