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To make software license auditing simpler, use SPDX[0] license
identifiers instead of duplicating the license text in every file.
NOTE: Files that have been imported by FreeBSD have not been modified.
[0]: https://spdx.org/
Change-Id: I80a00e1f641b8cc075ca5a95b10607ed9ed8761a
Signed-off-by: dp-arm <dimitris.papastamos@arm.com>
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Introduce new build option ENABLE_STACK_PROTECTOR. It enables
compilation of all BL images with one of the GCC -fstack-protector-*
options.
A new platform function plat_get_stack_protector_canary() is introduced.
It returns a value that is used to initialize the canary for stack
corruption detection. Returning a random value will prevent an attacker
from predicting the value and greatly increase the effectiveness of the
protection.
A message is printed at the ERROR level when a stack corruption is
detected.
To be effective, the global data must be stored at an address
lower than the base of the stacks. Failure to do so would allow an
attacker to overwrite the canary as part of an attack which would void
the protection.
FVP implementation of plat_get_stack_protector_canary is weak as
there is no real source of entropy on the FVP. It therefore relies on a
timer's value, which could be predictable.
Change-Id: Icaaee96392733b721fa7c86a81d03660d3c1bc06
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
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Introduce zeromem_dczva function on AArch64 that can handle unaligned
addresses and make use of DC ZVA instruction to zero a whole block at a
time. This zeroing takes place directly in the cache to speed it up
without doing external memory access.
Remove the zeromem16 function on AArch64 and replace it with an alias to
zeromem. This zeromem16 function is now deprecated.
Remove the 16-bytes alignment constraint on __BSS_START__ in
firmware-design.md as it is now not mandatory anymore (it used to comply
with zeromem16 requirements).
Change the 16-bytes alignment constraints in SP min's linker script to a
8-bytes alignment constraint as the AArch32 zeromem implementation is now
more efficient on 8-bytes aligned addresses.
Introduce zero_normalmem and zeromem helpers in platform agnostic header
that are implemented this way:
* AArch32:
* zero_normalmem: zero using usual data access
* zeromem: alias for zero_normalmem
* AArch64:
* zero_normalmem: zero normal memory using DC ZVA instruction
(needs MMU enabled)
* zeromem: zero using usual data access
Usage guidelines: in most cases, zero_normalmem should be preferred.
There are 2 scenarios where zeromem (or memset) must be used instead:
* Code that must run with MMU disabled (which means all memory is
considered device memory for data accesses).
* Code that fills device memory with null bytes.
Optionally, the following rule can be applied if performance is
important:
* Code zeroing small areas (few bytes) that are not secrets should use
memset to take advantage of compiler optimizations.
Note: Code zeroing security-related critical information should use
zero_normalmem/zeromem instead of memset to avoid removal by
compilers' optimizations in some cases or misbehaving versions of GCC.
Fixes ARM-software/tf-issues#408
Change-Id: Iafd9663fc1070413c3e1904e54091cf60effaa82
Signed-off-by: Douglas Raillard <douglas.raillard@arm.com>
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At the moment, all BL images share a similar memory layout: they start
with their code section, followed by their read-only data section.
The two sections are contiguous in memory. Therefore, the end of the
code section and the beginning of the read-only data one might share
a memory page. This forces both to be mapped with the same memory
attributes. As the code needs to be executable, this means that the
read-only data stored on the same memory page as the code are
executable as well. This could potentially be exploited as part of
a security attack.
This patch introduces a new build flag called
SEPARATE_CODE_AND_RODATA, which isolates the code and read-only data
on separate memory pages. This in turn allows independent control of
the access permissions for the code and read-only data.
This has an impact on memory footprint, as padding bytes need to be
introduced between the code and read-only data to ensure the
segragation of the two. To limit the memory cost, the memory layout
of the read-only section has been changed in this case.
- When SEPARATE_CODE_AND_RODATA=0, the layout is unchanged, i.e.
the read-only section still looks like this (padding omitted):
| ... |
+-------------------+
| Exception vectors |
+-------------------+
| Read-only data |
+-------------------+
| Code |
+-------------------+ BLx_BASE
In this case, the linker script provides the limits of the whole
read-only section.
- When SEPARATE_CODE_AND_RODATA=1, the exception vectors and
read-only data are swapped, such that the code and exception
vectors are contiguous, followed by the read-only data. This
gives the following new layout (padding omitted):
| ... |
+-------------------+
| Read-only data |
+-------------------+
| Exception vectors |
+-------------------+
| Code |
+-------------------+ BLx_BASE
In this case, the linker script now exports 2 sets of addresses
instead: the limits of the code and the limits of the read-only
data. Refer to the Firmware Design guide for more details. This
provides platform code with a finer-grained view of the image
layout and allows it to map these 2 regions with the appropriate
access permissions.
Note that SEPARATE_CODE_AND_RODATA applies to all BL images.
Change-Id: I936cf80164f6b66b6ad52b8edacadc532c935a49
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On the ARMv8 architecture, cache maintenance operations by set/way on the last
level of integrated cache do not affect the system cache. This means that such a
flush or clean operation could result in the data being pushed out to the system
cache rather than main memory. Another CPU could access this data before it
enables its data cache or MMU. Such accesses could be serviced from the main
memory instead of the system cache. If the data in the sysem cache has not yet
been flushed or evicted to main memory then there could be a loss of
coherency. The only mechanism to guarantee that the main memory will be updated
is to use cache maintenance operations to the PoC by MVA(See section D3.4.11
(System level caches) of ARMv8-A Reference Manual (Issue A.g/ARM DDI0487A.G).
This patch removes the reliance of Trusted Firmware on the flush by set/way
operation to ensure visibility of data in the main memory. Cache maintenance
operations by MVA are now used instead. The following are the broad category of
changes:
1. The RW areas of BL2/BL31/BL32 are invalidated by MVA before the C runtime is
initialised. This ensures that any stale cache lines at any level of cache
are removed.
2. Updates to global data in runtime firmware (BL31) by the primary CPU are made
visible to secondary CPUs using a cache clean operation by MVA.
3. Cache maintenance by set/way operations are only used prior to power down.
NOTE: NON-UPSTREAM TRUSTED FIRMWARE CODE SHOULD MAKE EQUIVALENT CHANGES IN
ORDER TO FUNCTION CORRECTLY ON PLATFORMS WITH SUPPORT FOR SYSTEM CACHES.
Fixes ARM-software/tf-issues#205
Change-Id: I64f1b398de0432813a0e0881d70f8337681f6e9a
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This patch adds the authentication framework that will be used as
the base to implement Trusted Board Boot in the Trusted Firmware.
The framework comprises the following modules:
- Image Parser Module (IPM)
This module is responsible for interpreting images, check
their integrity and extract authentication information from
them during Trusted Board Boot.
The module currently supports three types of images i.e.
raw binaries, X509v3 certificates and any type specific to
a platform. An image parser library must be registered for
each image type (the only exception is the raw image parser,
which is included in the main module by default).
Each parser library (if used) must export a structure in a
specific linker section which contains function pointers to:
1. Initialize the library
2. Check the integrity of the image type supported by
the library
3. Extract authentication information from the image
- Cryptographic Module (CM)
This module is responsible for verifying digital signatures
and hashes. It relies on an external cryptographic library
to perform the cryptographic operations.
To register a cryptographic library, the library must use the
REGISTER_CRYPTO_LIB macro, passing function pointers to:
1. Initialize the library
2. Verify a digital signature
3. Verify a hash
Failing to register a cryptographic library will generate
a build time error.
- Authentication Module (AM)
This module provides methods to authenticate an image, like
hash comparison or digital signatures. It uses the image parser
module to extract authentication parameters, the crypto module
to perform cryptographic operations and the Chain of Trust to
authenticate the images.
The Chain of Trust (CoT) is a data structure that defines the
dependencies between images and the authentication methods
that must be followed to authenticate an image.
The Chain of Trust, when added, must provide a header file named
cot_def.h with the following definitions:
- COT_MAX_VERIFIED_PARAMS
Integer value indicating the maximum number of authentication
parameters an image can present. This value will be used by the
authentication module to allocate the memory required to load
the parameters in the image descriptor.
Change-Id: Ied11bd5cd410e1df8767a1df23bb720ce7e58178
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This patch extends the build option `USE_COHERENT_MEMORY` to
conditionally remove coherent memory from the memory maps of
all boot loader stages. The patch also adds necessary
documentation for coherent memory removal in firmware-design,
porting and user guides.
Fixes ARM-Software/tf-issues#106
Change-Id: I260e8768c6a5c2efc402f5804a80657d8ce38773
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This patch fixes the incorrect value of the LENGTH attribute in
the linker scripts. This attribute must define the memory size, not
the limit address.
Fixes ARM-software/tf-issues#252
Change-Id: I328c38b9ec502debe12046a8912d7dfc54610c46
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Secure ROM at address 0x0000_0000 is defined as FVP_TRUSTED_ROM
Secure RAM at address 0x0400_0000 is defined as FVP_TRUSTED_SRAM
Secure RAM at address 0x0600_0000 is defined as FVP_TRUSTED_DRAM
BLn_BASE and BLn_LIMIT definitions have been updated and are based on
these new memory regions.
The available memory for each bootloader in the linker script is
defined by BLn_BASE and BLn_LIMIT, instead of the complete memory
region.
TZROM_BASE/SIZE and TZRAM_BASE/SIZE are no longer required as part of
the platform porting.
FVP common definitions are defined in fvp_def.h while platform_def.h
contains exclusively (with a few exceptions) the definitions that are
mandatory in the porting guide. Therefore, platform_def.h now includes
fvp_def.h instead of the other way around.
Porting guide has been updated to reflect these changes.
Change-Id: I39a6088eb611fc4a347db0db4b8f1f0417dbab05
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Previously, platform.h contained many declarations and definitions
used for different purposes. This file has been split so that:
* Platform definitions used by common code that must be defined
by the platform are now in platform_def.h. The exact include
path is exported through $PLAT_INCLUDES in the platform makefile.
* Platform definitions specific to the FVP platform are now in
/plat/fvp/fvp_def.h.
* Platform API declarations specific to the FVP platform are now
in /plat/fvp/fvp_private.h.
* The remaining platform API declarations that must be ported by
each platform are still in platform.h but this file has been
moved to /include/plat/common since this can be shared by all
platforms.
Change-Id: Ieb3bb22fbab3ee8027413c6b39a783534aee474a
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Currently the platform code gets to define the base address of each
boot loader image. However, the linker scripts couteract this
flexibility by enforcing a fixed overall layout of the different
images. For example, they require that the BL3-1 image sits below
the BL2 image. Choosing BL3-1 and BL2 base addresses in such a way
that it violates this constraint makes the build fail at link-time.
This patch requires the platform code to now define a limit address
for each image. The linker scripts check that the image fits within
these bounds so they don't rely anymore on the position of a given
image in regard to the others.
Fixes ARM-software/tf-issues#163
Change-Id: I8c108646825da19a6a8dfb091b613e1dd4ae133c
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All common functions are being built into all binary images,
whether or not they are actually used. This change enables the
use of -ffunction-sections, -fdata-sections and --gc-sections
in the compiler and linker to remove unused code and data from
the images.
Change-Id: Ia9f78c01054ac4fa15d145af38b88a0d6fb7d409
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At present, the entry point for each BL image is specified via the
Makefiles and provided on the command line to the linker. When using a
link script the entry point should rather be specified via the ENTRY()
directive in the link script.
This patch updates linker scripts of all BL images to specify the entry
point using the ENTRY() directive. It also removes the --entry flag
passed to the linker through Makefile.
Fixes issue ARM-software/tf-issues#66
Change-Id: I1369493ebbacea31885b51185441f6b628cf8da0
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The BL31 and BL2 linker scripts ended up having duplicate descriptions
for xlat_tables section. This patch removes those duplicate
descriptions.
Change-Id: Ibbdda0902c57fca5ea4e91e0baefa6df8f0a9bb1
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This patch factors out the ARM FVP specific code to create MMU
translation tables so that it is possible for a boot loader stage to
create a different set of tables instead of using the default ones.
The default translation tables are created with the assumption that
the calling boot loader stage executes out of secure SRAM. This might
not be true for the BL3_2 stage in the future.
A boot loader stage can define the `fill_xlation_tables()` function as
per its requirements. It returns a reference to the level 1
translation table which is used by the common platform code to setup
the TTBR_EL3.
This patch is a temporary solution before a larger rework of
translation table creation logic is introduced.
Change-Id: I09a075d5da16822ee32a411a9dbe284718fb4ff6
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This patch ensures that VBAR_EL3 points to the simple stack-less
'early_exceptions' when the C runtime stack is not correctly setup to
use the more complex 'runtime_exceptions'. It is initialised to
'runtime_exceptions' once this is done.
This patch also moves all exception vectors into a '.vectors' section
and modifies linker scripts to place all such sections together. This
will minimize space wastage from alignment restrictions.
Change-Id: I8c3e596ea3412c8bd582af9e8d622bb1cb2e049d
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This patch moves the translation tables into their own section. This
saves space that would otherwise have been lost in padding due to page
table alignment constraints. The BL31 and BL32 bases have been
consequently adjusted.
Change-Id: Ibd65ae8a5ce4c4ea9a71a794c95bbff40dc63e65
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Change-Id: Ic7fb61aabae1d515b9e6baf3dd003807ff42da60
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- Add instructions for contributing to ARM Trusted Firmware.
- Update copyright text in all files to acknowledge contributors.
Change-Id: I9311aac81b00c6c167d2f8c889aea403b84450e5
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- Check at link-time that bootloader images will fit in memory
at run time and that they won't overlap each other.
- Remove text and rodata orphan sections.
- Define new linker symbols to remove the need for platform setup
code to know the order of sections.
- Reduce the size of the raw binary images by cutting some sections
out of the disk image and allocating them at load time, whenever
possible.
- Rework alignment constraints on sections.
- Remove unused linker symbols.
- Homogenize linker symbols names across all BLs.
- Add some comments in the linker scripts.
Change-Id: I47a328af0ccc7c8ab47fcc0dc6e7dd26160610b9
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