2.4. Building Supporting Tools
Note
OpenSSL 3.0 is needed in order to build the tools. A custom installation
can be used if not updating the OpenSSL version on the OS. In order to do
this, use the OPENSSL_DIR
variable after the make
command to
indicate the location of the custom OpenSSL build. Then, to run the tools,
use the LD_LIBRARY_PATH
to indicate the location of the built
libraries. More info about OPENSSL_DIR
can be found at
Build Options.
2.4.1. Building and using the FIP tool
The following snippets build a FIP for the FVP platform. While it is not an intrinsic part of the FIP format, a BL33 image is required for these examples. For the purposes of experimentation, Trusted Firmware-A Tests (tftf.bin`) may be used. Refer to to the TFTF documentation for instructions on building a TFTF binary.
The TF-A build system provides the make target fip
to create a FIP file
for the specified platform using the FIP creation tool included in the TF-A
project. Examples below show how to build a FIP file for FVP, packaging TF-A
and BL33 images.
For AArch64:
make PLAT=fvp BL33=<path-to>/bl33.bin fip
For AArch32:
make PLAT=fvp ARCH=aarch32 AARCH32_SP=sp_min BL33=<path-to>/bl33.bin fip
The resulting FIP may be found in:
build/fvp/<build-type>/fip.bin
For advanced operations on FIP files, it is also possible to independently build the tool and create or modify FIPs using this tool. To do this, follow these steps:
It is recommended to remove old artifacts before building the tool:
make -C tools/fiptool clean
Build the tool:
make [DEBUG=1] [V=1] fiptool
The tool binary can be located in:
./tools/fiptool/fiptool
Invoking the tool with help
will print a help message with all available
options.
Example 1: create a new Firmware package fip.bin
that contains BL2 and BL31:
./tools/fiptool/fiptool create \
--tb-fw build/<platform>/<build-type>/bl2.bin \
--soc-fw build/<platform>/<build-type>/bl31.bin \
fip.bin
Example 2: view the contents of an existing Firmware package:
./tools/fiptool/fiptool info <path-to>/fip.bin
Example 3: update the entries of an existing Firmware package:
# Change the BL2 from Debug to Release version
./tools/fiptool/fiptool update \
--tb-fw build/<platform>/release/bl2.bin \
build/<platform>/debug/fip.bin
Example 4: unpack all entries from an existing Firmware package:
# Images will be unpacked to the working directory
./tools/fiptool/fiptool unpack <path-to>/fip.bin
Example 5: remove an entry from an existing Firmware package:
./tools/fiptool/fiptool remove \
--tb-fw build/<platform>/debug/fip.bin
Note that if the destination FIP file exists, the create, update and remove operations will automatically overwrite it.
The unpack operation will fail if the images already exist at the destination. In that case, use -f or –force to continue.
More information about FIP can be found in the Firmware Design document.
2.4.2. Building the Certificate Generation Tool
The cert_create
tool is built as part of the TF-A build process when the
fip
make target is specified and TBB is enabled (as described in the
previous section), but it can also be built separately with the following
command:
make PLAT=<platform> [DEBUG=1] [V=1] certtool
For platforms that require their own IDs in certificate files, the generic
‘cert_create’ tool can be built with the following command. Note that the target
platform must define its IDs within a platform_oid.h
header file for the
build to succeed.
make PLAT=<platform> USE_TBBR_DEFS=0 [DEBUG=1] [V=1] certtool
DEBUG=1
builds the tool in debug mode. V=1
makes the build process more
verbose. The following command should be used to obtain help about the tool:
./tools/cert_create/cert_create -h
2.4.2.1. Building the Firmware Encryption Tool
The encrypt_fw
tool is built as part of the TF-A build process when the
fip
make target is specified, DECRYPTION_SUPPORT and TBB are enabled, but
it can also be built separately with the following command:
make PLAT=<platform> [DEBUG=1] [V=1] enctool
DEBUG=1
builds the tool in debug mode. V=1
makes the build process more
verbose. The following command should be used to obtain help about the tool:
./tools/encrypt_fw/encrypt_fw -h
Note that the enctool in its current implementation only supports encryption key to be provided in plain format. A typical implementation can very well extend this tool to support custom techniques to protect encryption key.
Also, a user may choose to provide encryption key or nonce as an input file
via using cat <filename>
instead of a hex string.
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