Commit Graph

8 Commits

Author SHA1 Message Date
Ard Biesheuvel 4febfb8dd0 efi: Replace GPL license boilerplate with SPDX headers
Replace all GPL license blurbs with an equivalent SPDX header (most
files are GPLv2, some are GPLv2+). While at it, drop some outdated
header changelogs as well.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: AKASHI Takahiro <takahiro.akashi@linaro.org>
Cc: Alexander Graf <agraf@suse.de>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Jones <pjones@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20190202094119.13230-7-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-02-04 08:27:25 +01:00
Ard Biesheuvel c2ceb5fd4e efi/random: Increase size of firmware supplied randomness
The crng code requires at least 64 bytes (2 * CHACHA20_BLOCK_SIZE)
to complete the fast boot-time init, so provide that many bytes
when invoking UEFI protocols to seed the entropy pool. Also, add
a notice so we can tell from the boot log when the seeding actually
took place.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825155019.6740-3-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-26 09:20:33 +02:00
Ard Biesheuvel 018edcfac4 efi/libstub: Make efi_random_alloc() allocate below 4 GB on 32-bit
The UEFI stub executes in the context of the firmware, which identity
maps the available system RAM, which implies that only memory below
4 GB can be used for allocations on 32-bit architectures, even on [L]PAE
capable hardware.

So ignore any reported memory above 4 GB in efi_random_alloc(). This
also fixes a reported build problem on ARM under -Os, where the 64-bit
logical shift relies on a software routine that the ARM decompressor does
not provide.

A second [minor] issue is also fixed, where the '+ 1' is moved out of
the shift, where it belongs: the reason for its presence is that a
memory region where start == end should count as a single slot, given
that 'end' takes the desired size and alignment of the allocation into
account.

To clarify the code in this regard, rename start/end to 'first_slot' and
'last_slot', respectively, and introduce 'region_end' to describe the
last usable address of the current region.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/1480010543-25709-2-git-send-email-ard.biesheuvel@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-25 07:15:23 +01:00
Ard Biesheuvel 568bc4e870 efi/arm*/libstub: Invoke EFI_RNG_PROTOCOL to seed the UEFI RNG table
Invoke the EFI_RNG_PROTOCOL protocol in the context of the stub and
install the Linux-specific RNG seed UEFI config table. This will be
picked up by the EFI routines in the core kernel to seed the kernel
entropy pool.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-6-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-13 08:23:15 +01:00
Ard Biesheuvel a6a144698d efi/libstub: Add random.c to ARM build
Make random.c build for ARM by moving the fallback definition of
EFI_ALLOC_ALIGN to efistub.h, and replacing a division by a value
we know to be a power of 2 with a right shift (this is required since
ARM does not have any integer division helper routines in its decompressor)

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-efi@vger.kernel.org
Link: http://lkml.kernel.org/r/20161112213237.8804-5-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-13 08:23:15 +01:00
Jeffrey Hugo dadb57abc3 efi/libstub: Allocate headspace in efi_get_memory_map()
efi_get_memory_map() allocates a buffer to store the memory map that it
retrieves.  This buffer may need to be reused by the client after
ExitBootServices() is called, at which point allocations are not longer
permitted.  To support this usecase, provide the allocated buffer size back
to the client, and allocate some additional headroom to account for any
reasonable growth in the map that is likely to happen between the call to
efi_get_memory_map() and the client reusing the buffer.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-05 12:18:17 +01:00
Ard Biesheuvel 2ddbfc81ea efi: stub: add implementation of efi_random_alloc()
This implements efi_random_alloc(), which allocates a chunk of memory of
a certain size at a certain alignment, and uses the random_seed argument
it receives to randomize the address of the allocation.

This is implemented by iterating over the UEFI memory map, counting the
number of suitable slots (aligned offsets) within each region, and picking
a random number between 0 and 'number of slots - 1' to select the slot,
This should guarantee that each possible offset is chosen equally likely.

Suggested-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24 14:57:28 +00:00
Ard Biesheuvel e4fbf47674 efi: stub: implement efi_get_random_bytes() based on EFI_RNG_PROTOCOL
This exposes the firmware's implementation of EFI_RNG_PROTOCOL via a new
function efi_get_random_bytes().

Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-24 14:57:28 +00:00