Michael Brown [Sat, 12 Mar 2016 17:42:30 +0000 (17:42 +0000)]
[linda] Use standard readq() and writeq() implementations
This driver is the original source of the current readq() and writeq()
implementations for 32-bit iPXE. Switch to using the now-centralised
definitions, to avoid including architecture-specific code in an
otherwise architecture-independent driver.
Michael Brown [Sat, 12 Mar 2016 12:39:17 +0000 (12:39 +0000)]
[librm] Do not unconditionally preserve flags across virt_call()
Commit 196f0f2 ("[librm] Convert prot_call() to a real-mode near
call") introduced a regression in which any deliberate modification to
the low 16 bits of the CPU flags (in struct i386_all_regs) would be
overwritten with the original flags value at the time of entry to
prot_call().
The regression arose because the alignment requirements of the
protected-mode stack necessitated the insertion of two bytes of
padding immediately below the prot_call() return address. The
solution chosen was to extend the existing "pushfl / popfl" pair to
"pushfw;pushfl / popfl;popfw". The extra "pushfw / popfw" appears at
first glance to be a no-op, but fails to take into account the fact
that the flags restored by popfl may have been deliberately modified
by the protected-mode function.
Fix by replacing "pushfw / popfw" with "pushw %ss / popw %ss". While
%ss does appear within struct i386_all_regs, any modification to the
stored value has always been ignored by prot_call() anyway.
The most visible symptom of this regression was that SAN booting would
fail since every INT 13 call would be chained to the original INT 13
vector.
Reported-by: Vishvananda Ishaya <vishvananda@gmail.com> Reported-by: Jamie Thompson <forum.ipxe@jamie-thompson.co.uk> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Sat, 12 Mar 2016 01:21:18 +0000 (01:21 +0000)]
[arp] Validate length of ARP packet
There is no practical way to generate an underlength ARP packet since
an ARP packet is always padded up to the minimum Ethernet frame length
(or dropped by the receiving Ethernet hardware if incorrectly padded),
but the absence of an explicit check causes warnings from some
analysis tools.
Fix by adding an explicit check on the I/O buffer length.
Michael Brown [Fri, 11 Mar 2016 16:51:13 +0000 (16:51 +0000)]
[crypto] Allow for zero-length ASN.1 cursors
The assumption in asn1_type() that an ASN.1 cursor will always contain
a type byte is incorrect. A cursor that has been cleanly invalidated
via asn1_invalidate_cursor() will contain a type byte, but there are
other ways in which to arrive at a zero-length cursor.
Fix by explicitly checking the cursor length in asn1_type(). This
allows asn1_invalidate_cursor() to be reduced to simply zeroing the
length field.
Michael Brown [Fri, 11 Mar 2016 16:09:40 +0000 (16:09 +0000)]
[tls] Avoid potential out-of-bound reads in length fields
Many TLS records contain variable-length fields. We currently
validate the overall record length, but do so only after reading the
length of the variable-length field. If the record is too short to
even contain the length field, then we may read uninitialised data
from beyond the end of the record.
This is harmless in practice (since the subsequent overall record
length check would fail regardless of the value read from the
uninitialised length field), but causes warnings from some analysis
tools.
Fix by validating that the overall record length is sufficient to
contain the length field before reading from the length field.
Michael Brown [Thu, 10 Mar 2016 18:06:26 +0000 (18:06 +0000)]
[efi] Work around broken GetFontInfo() implementations
Several UEFI platforms are known to return EFI_NOT_FOUND when asked to
retrieve the system default font information via GetFontInfo(). Work
around these broken platforms by iterating over the glyphs to find the
maximum height used by a printable character.
Originally-fixed-by: Jonathan Dieter <jdieter@lesbg.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Wed, 9 Mar 2016 00:51:08 +0000 (00:51 +0000)]
[eoib] Support non-FullMember gateway devices
Some EoIB implementations utilise an EoIB-to-Ethernet gateway device
that does not perform a FullMember join to the multicast group for the
EoIB broadcast domain. This has various exciting side-effects, such
as requiring every EoIB node to send every broadcast packet twice.
As an added bonus, the gateway may also break the EoIB MAC address to
GID mapping protocol by sending Ethernet-sourced packets from the
wrong QPN.
Michael Brown [Wed, 9 Mar 2016 00:45:09 +0000 (00:45 +0000)]
[eoib] Allow the multicast group to be forcefully created
Some EoIB implementations require each individual EoIB node to create
the multicast group for the EoIB broadcast domain.
It is left as an exercise for the interested reader to determine how
such an implementation might ever allow the parameters of such a
multicast group to be changed without requiring a simultaneous upgrade
of every driver on every operating system on every machine currently
attached to the fabric.
Michael Brown [Wed, 9 Mar 2016 00:26:56 +0000 (00:26 +0000)]
[eoib] Add Ethernet over Infiniband (EoIB) driver
EoIB is a fairly simple protocol in which raw Ethernet frames
(excluding the CRC) are encapsulated within Infiniband Unreliable
Datagrams, with a four-byte fixed EoIB header (which conveys no actual
information). The Ethernet broadcast domain is provided by a
multicast group, similar to the IPoIB IPv4 multicast group.
The mapping from Ethernet MAC addresses to Infiniband address vectors
is achieved by snooping incoming traffic and building a peer cache
which can then be used to map a MAC address into a port GID. The
address vector is completed using a path record lookup, as for IPoIB.
Note that this requires every packet to include a GRH.
Add basic support for EoIB devices. This driver is substantially
derived from the IPoIB driver. There is currently no mechanism for
automatically creating EoIB devices.
Michael Brown [Tue, 8 Mar 2016 17:02:24 +0000 (17:02 +0000)]
[ipoib] Resimplify test for received broadcast packets
Commit e62e52b ("[ipoib] Simplify test for received broadcast
packets") relies upon the multicast LID being present in the
destination address vector as passed to ipoib_complete_recv().
Unfortunately, this information is not present in many Infiniband
devices' completion queue entries.
Fix by testing instead for the presence of a multicast GID.
Michael Brown [Tue, 8 Mar 2016 13:06:06 +0000 (13:06 +0000)]
[pcbios] Restrict external memory allocations to the low 4GB
When running the 64-bit BIOS version of iPXE, restrict external memory
allocations to the low 4GB to ensure that allocations (such as for
initrds) fall within our identity-mapped memory region, and will be
accessible to the potentially 32-bit operating system.
Move largest_memblock() back to memtop_umalloc.c, since this change
imposes a restriction that applies only to BIOS builds.
Michael Brown [Wed, 2 Mar 2016 09:29:33 +0000 (09:29 +0000)]
[infiniband] Avoid multiple calls to ib_cmrc_shutdown()
When a CMRC connection is closed, the deferred shutdown process calls
ib_destroy_qp(). This will cause the receive work queue entries to
complete in error (since they are being cancelled), which will in turn
reschedule the deferred shutdown process. This eventually leads to
ib_destroy_conn() being called on a connection that has already been
freed.
Fix by explicitly cancelling any pending shutdown process after the
shutdown process has completed.
Ironically, this almost exactly reverts commit 019d4c1 ("[infiniband]
Use a one-shot process for CMRC shutdown"); prior to the introduction
of one-shot processes the only way to achieve a one-shot process was
for the process to cancel itself.
Michael Brown [Thu, 18 Feb 2016 02:44:19 +0000 (02:44 +0000)]
[librm] Add support for running in 64-bit long mode
Add support for running the BIOS version of iPXE in 64-bit long mode.
A 64-bit BIOS version of iPXE can be built using e.g.
make bin-x86_64-pcbios/ipxe.usb
make bin-x86_64-pcbios/8086100e.mrom
The 64-bit BIOS version should appear to function identically to the
normal 32-bit BIOS version. The physical memory layout is unaltered:
iPXE is still relocated to the top of the available 32-bit address
space. The code is linked to a virtual address of 0xffffffffeb000000
(in the negative 2GB as required by -mcmodel=kernel), with 4kB pages
created to cover the whole of .textdata. 2MB pages are created to
cover the whole of the 32-bit address space.
The 32-bit portions of the code run with VIRTUAL_CS and VIRTUAL_DS
configured such that truncating a 64-bit virtual address gives a
32-bit virtual address pointing to the same physical location.
The stack pointer remains as a physical address when running in long
mode (although the .stack section is accessible via the negative 2GB
virtual address); this is done in order to simplify the handling of
interrupts occurring while executing a portion of 32-bit code with
flat physical addressing via PHYS_CODE().
Interrupts may be enabled in either 64-bit long mode, 32-bit protected
mode with virtual addresses, 32-bit protected mode with physical
addresses, or 16-bit real mode. Interrupts occurring in any mode
other than real mode will be reflected down to real mode and handled
by whichever ISR is hooked into the BIOS interrupt vector table.
Michael Brown [Sun, 21 Feb 2016 11:37:37 +0000 (11:37 +0000)]
[librm] Support userptr_t in 64-bit builds
In a 64-bit build, the entirety of the 32-bit address space is
identity-mapped and so any valid physical address may immediately be
used as a virtual address. Conversely, a virtual address that is
already within the 32-bit address space may immediately be used as a
physical address.
A valid virtual address that lies outside the 32-bit address space
must be an address within .textdata, and so can be converted to a
physical address by adding virt_offset.
Michael Brown [Sun, 21 Feb 2016 11:13:04 +0000 (11:13 +0000)]
[librm] Mark virt_offset, text16, data16, rm_cs, and rm_ds as constant
The physical locations of .textdata, .text16 and .data16 are constant
from the point of view of C code. Mark the relevant variables as
constant to allow gcc to optimise out redundant reads.
Michael Brown [Fri, 19 Feb 2016 19:43:04 +0000 (19:43 +0000)]
[librm] Add phys_call() wrapper for calling code with physical addressing
Add a phys_call() wrapper function (analogous to the existing
real_call() wrapper function) for calling code with flat physical
addressing, and use this wrapper within the PHYS_CODE() macro.
Move the relevant functionality inside librm.S, where it more
naturally belongs.
The COMBOOT code currently uses explicit calls to _virt_to_phys and
_phys_to_virt. These will need to be rewritten if our COMBOOT support
is ever generalised to be able to run in a 64-bit build.
Specifically:
- com32_exec_loop() should be restructured to use PHYS_CODE()
- com32_wrapper.S should be restructured to use an equivalent of
prot_call(), passing parameters via a struct i386_all_regs
- there appears to be no need for com32_wrapper.S to switch between
external and internal stacks; this could be omitted to simplify
the design.
For now, librm.S continues to expose _virt_to_phys and _phys_to_virt
for use by com32.c and com32_wrapper.S. Similarly, librm.S continues
to expose _intr_to_virt for use by gdbidt.S.
Michael Brown [Fri, 19 Feb 2016 19:45:23 +0000 (19:45 +0000)]
[build] Fix building on older versions of binutils
Some older versions of binutils have issues with both the use of
PROVIDE() and the interpretation of numeric literals within a section
description.
Work around these older versions by defining the required numeric
literals outside of any section description, and by automatically
determining whether or not to generate extra space for page tables
rather than relying on LDFLAGS.
Michael Brown [Fri, 19 Feb 2016 01:50:13 +0000 (01:50 +0000)]
[librm] Prepare for long-mode memory map
The bulk of the iPXE binary (the .textdata section) is physically
relocated at runtime to the top of the 32-bit address space in order
to allow space for an OS to be loaded. The relocation is achieved
with the assistance of segmentation: we adjust the code and data
segment bases so that the link-time addresses remain valid.
Segmentation is not available (for normal code and data segments) in
long mode. We choose to compile the C code with -mcmodel=kernel and
use a link-time address of 0xffffffffeb000000. This choice allows us
to identity-map the entirety of the 32-bit address space, and to alias
our chosen link-time address to the physical location of our .textdata
section. (This requires the .textdata section to always be aligned to
a page boundary.)
We simultaneously choose to set the 32-bit virtual address segment
bases such that the link-time addresses may simply be truncated to 32
bits in order to generate a valid 32-bit virtual address. This allows
symbols in .textdata to be trivially accessed by both 32-bit and
64-bit code.
There is no (sensible) way in 32-bit assembly code to generate the
required R_X86_64_32S relocation records for these truncated symbols.
However, subtracting the fixed constant 0xffffffff00000000 has the
same effect as truncation, and can be represented in a standard
R_X86_64_32 relocation record. We define the VIRTUAL() macro to
abstract away this truncation operation, and apply it to all
references by 32-bit (or 16-bit) assembly code to any symbols within
the .textdata section.
We define "virt_offset" for a 64-bit build as "the value to be added
to an address within .textdata in order to obtain its physical
address". With this definition, the low 32 bits of "virt_offset" can
be treated by 32-bit code as functionally equivalent to "virt_offset"
in a 32-bit build.
We define "text16" and "data16" for a 64-bit build as the physical
addresses of the .text16 and .data16 sections. Since a physical
address within the 32-bit address space may be used directly as a
64-bit virtual address (thanks to the identity map), this definition
provides the most natural access to variables in .text16 and .data16.
Note that this requires a minor adjustment in prot_to_real(), which
accesses .text16 using 32-bit virtual addresses.
Michael Brown [Fri, 19 Feb 2016 00:56:20 +0000 (00:56 +0000)]
[librm] Transition to protected mode within init_librm()
Long-mode operation will require page tables, which are too large to
sensibly fit in our .data16 segment in base memory.
Add a portion of init_librm() running in 32-bit protected mode to
provide access to high memory. Use this portion of init_librm() to
initialise the .textdata variables "virt_offset", "text16", and
"data16", eliminating the redundant (re)initialisation currently
performed on every mode transition as part of real_to_prot().
Michael Brown [Thu, 18 Feb 2016 14:38:41 +0000 (14:38 +0000)]
[bios] Make uses of REAL_CODE() and PHYS_CODE() 64-bit clean
On a 64-bit CPU, any modification of a register by 32-bit or 16-bit
code will destroy the invisible upper 32 bits of the corresponding
64-bit register. For example: a 32-bit "pushl %eax" followed by a
"popl %eax" will zero the upper half of %rax. This differs from the
treatment of upper halves of 32-bit registers by 16-bit code: a
"pushw %ax" followed by a "popw %ax" will leave the upper 16 bits of
%eax unmodified.
Inline assembly generated using REAL_CODE() or PHYS_CODE() will
therefore have to preserve the upper halves of all registers, to avoid
clobbering registers that gcc expects to be preserved.
Output operands from REAL_CODE() and PHYS_CODE() assembly may
therefore contain undefined values in the upper 32 bits.
Fix by using explicit variable widths (e.g. uint32_t) for
non-discarded output operands, to ensure that undefined values in the
upper 32 bits of 64-bit registers are ignored.
Michael Brown [Fri, 12 Feb 2016 13:59:06 +0000 (13:59 +0000)]
[prefix] Pad .text16 and .data16 segment sizes at build time
Commit c64747d ("[librm] Speed up real-to-protected mode transition
under KVM") rounded down the .text16 segment address calculated in
alloc_basemem() to a multiple of 64 bytes in order to speed up mode
transitions under KVM.
This creates a potential discrepancy between alloc_basemem() and
free_basemem(), meaning that free_basemem() may free less memory than
was allocated by alloc_basemem().
Fix by padding the calculated sizes of both .text16 and .data16 to a
multiple of 64 bytes at build time.
Debugged-by: Yossef Efraim <yossefe@mellanox.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Thu, 11 Feb 2016 18:44:24 +0000 (18:44 +0000)]
[iobuf] Improve robustness of I/O buffer allocation
Guard against various corner cases (such as zero-length buffers, zero
alignments, and integer overflow when rounding up allocation lengths
and alignments) and ensure that the struct io_buffer is correctly
aligned even when the caller requests a non-zero alignment for the I/O
buffer itself.
Add self-tests to verify that the resulting alignments and lengths are
correct for a range of allocations.
Michael Brown [Sat, 6 Feb 2016 10:20:57 +0000 (10:20 +0000)]
[malloc] Guard against unsigned integer overflow
Commit f3fbb5f ("[malloc] Avoid integer overflow for excessively large
memory allocations") fixed signed integer overflow issues caused by
the use of ssize_t, but did not guard against unsigned integer
overflow.
Add explicit checks for unsigned integer overflow where needed. As a
side bonus, erroneous calls to malloc_dma() with an (illegal) size of
zero will now fail cleanly.
Michael Brown [Thu, 28 Jan 2016 14:15:36 +0000 (14:15 +0000)]
[ath9k] Remove broken ath_rxbuf_alloc()
ath_rx_init() demonstrates some serious confusion over how to use
pointers, resulting in (uint32_t*)NULL being used as a temporary
variable. This does not end well.
The broken code in question is performing manual alignment of I/O
buffers, which can now be achieved more simply using alloc_iob_raw().
Fix by removing ath_rxbuf_alloc() entirely.
Michael Brown [Tue, 26 Jan 2016 16:16:13 +0000 (16:16 +0000)]
[uri] Apply URI decoding for all parsed URIs
The various early-exit paths in parse_uri() accidentally bypass the
URI field decoding. The result is that opaque or relative URIs do not
undergo URI field decoding, resulting in double-encoding when the URIs
are subsequently used. For example:
#!ipxe
set mac ${macstring}
imgfetch /boot/by-mac/${mac:uristring}
would result in an HTTP GET such as
GET /boot/by-mac/00%253A0c%253A29%253Ac5%253A39%253Aa1 HTTP/1.1
rather than the expected
GET /boot/by-mac/00%3A0c%3A29%3Ac5%3A39%3Aa1 HTTP/1.1
Fix by ensuring that URI decoding is always applied regardless of the
URI format.
Reported-by: Andrew Widdersheim <awiddersheim@inetu.net> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Thu, 21 Jan 2016 16:24:16 +0000 (16:24 +0000)]
[tftp] Mangle initial slash on TFTP URIs
TFTP URIs are intrinsically problematic, since:
- TFTP servers may use either normal slashes or backslashes as a
directory separator,
- TFTP servers allow filenames to be specified using relative paths
(with no initial directory separator),
- TFTP filenames present in a DHCP filename field may use special
characters such as "?" or "#" that prevent parsing as a generic URI.
As of commit 7667536 ("[uri] Refactor URI parsing and formatting"), we
have directly constructed TFTP URIs from DHCP next-server and filename
pairs, avoiding the generic URI parser. This eliminated the problems
related to special characters, but indirectly made it impossible to
parse a "tftp://..." URI string into a TFTP URI with a non-absolute
path.
Re-introduce the convention of requiring an extra slash in a
"tftp://..." URI string in order to specify a TFTP URI with an initial
slash in the filename. For example:
This is ugly, but there seems to be no other sensible way to provide
the ability to specify all possible TFTP filenames.
A side-effect of this change is that format_uri() will no longer add a
spurious initial "/" when formatting a relative URI string. This
improves the console output when fetching an image specified via a
relative URI.
Michael Brown [Thu, 21 Jan 2016 17:50:34 +0000 (17:50 +0000)]
[ocsp] Avoid including a double path separator in request URI
The OCSP responder URI included within an X.509 certificate may or may
not include a trailing slash. We currently rely on the fact that
format_uri() incorrectly inserts an initial slash, which we include
unconditionally within the OCSP request URI.
Switch to using uri_encode() directly, and insert a slash only if the
X.509 certificate's OCSP responder URI does not already include a
trailing slash.
Michael Brown [Tue, 19 Jan 2016 08:16:17 +0000 (08:16 +0000)]
[autoboot] Fix incorrect boolean logic
Commit 53d2d9e ("[uri] Generalise tftp_uri() to pxe_uri()") introduced
a regression in which an NFS root path would no longer be treated as
an unsupported root path, causing a boot with an NFS root path to fail
with a "Could not open SAN device" error.
Reported-by: David Evans <dave.evans55@googlemail.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Tue, 19 Jan 2016 00:04:33 +0000 (00:04 +0000)]
[smsc95xx] Reserve headroom in received packets
Some protocols (such as ARP) may modify the received packet and re-use
the same I/O buffer for transmission of a reply. The SMSC95XX
transmit header is larger than the receive header: the re-used I/O
buffer therefore does not have sufficient headroom for the transmit
header, and the ARP reply will therefore fail to be transmitted. This
is essentially the same problem as in commit 2e72d10 ("[ncm] Reserve
headroom in received packets").
Fix by reserving sufficient space at the start of each received packet
to allow for the difference between the lengths of the transmit and
receive headers.
This problem is not caught by the current driver development test
suite (documented at http://ipxe.org/dev/driver), since even the large
file transfer tests tend to completely sufficiently quickly that there
is no need for the server to ever send an ARP request. The failure
shows up only when using a very slow protocol such as RFC7440-enhanced
TFTP (as used by Windows Deployment Services).
Michael Brown [Wed, 13 Jan 2016 07:25:05 +0000 (07:25 +0000)]
[smsc95xx] Enable LEDs
The LED pins are configured by default as GPIO inputs. While it is
conceivable that a board might actually use these pins as GPIOs, no
such board is known to exist.
The Linux smsc95xx driver configures these pins unconditionally as LED
outputs. Assume that it is safe to do likewise.
Expose the network interface name (e.g. "net0") as a setting. This
allows a script to obtain the name of the most recently opened network
interface via ${netX/ifname}.
Signed-off-by: Andrew Widdersheim <amwiddersheim@gmail.com> Modified-by: Michael Brown <mcb30@ipxe.org> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Mon, 18 Jan 2016 08:37:27 +0000 (08:37 +0000)]
[build] Add named configuration for public cloud environments
Add a named CONFIG=cloud configuration, which enables console types
useful for obtaining output from virtual machines in public clouds
such as AWS EC2.
An image suitable for use in AWS EC2 can be built using
make bin/ipxe.usb CONFIG=cloud EMBED=config/cloud/aws.ipxe
The embedded script will direct iPXE to download and execute the EC2
"user-data" file, which is always available to an EC2 VM via the URI
http://169.254.169.254/latest/user-data (regardless of the VPC
networking settings). The boot can therefore be controlled by
modifying the per-instance user data, without having to modify the
boot disk image.
Console output can be obtained via syslog (with a syslog server
configured in the user-data script), via the AWS "System Log" (after
the instance has been stopped), or as a last resort from the log
partition on the boot disk.
Michael Brown [Thu, 14 Jan 2016 12:39:01 +0000 (12:39 +0000)]
[stp] Fix incorrectly disambiguated errors
The three nominally-disambiguated ENOTSUP errors accidentally all used
the same error disambiguator, rendering them identical. Fix by
changing all three values. We avoid reusing the 0x01 disambiguator
value, since that remains ambiguous in older binaries.
Michael Brown [Tue, 12 Jan 2016 15:35:06 +0000 (15:35 +0000)]
[debug] Allow debug colourisation to be disabled
Some BIOS console redirection capabilities do not work well with the
colourised debug messages used by iPXE. We already allow the range of
colours to be controlled via the DBGCOL=... build parameter. Extend
this syntax to allow DBGCOL=0 to be used to mean "disable colours".
Requested-by: Wissam Shoukair <wissams@mellanox.com> Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown [Tue, 12 Jan 2016 08:27:59 +0000 (08:27 +0000)]
[i386] Add check_bios_interrupts() debug function
Provide a debug function check_bios_interrupts() to look for changes
to the interrupt vector table. This can be useful when investigating
the behaviour (including crashes) of external PXE NBPs.