Hi Takahiro,
On Thu, 28 Oct 2021 at 23:20, AKASHI Takahiro
<takahiro.aka...@linaro.org> wrote:
>
> On Thu, Oct 28, 2021 at 09:17:48PM -0600, Simon Glass wrote:
> > Hi Takahiro,
> >
> > On Thu, 28 Oct 2021 at 00:25, AKASHI Takahiro
> > <takahiro.aka...@linaro.org> wrote:
> > >
> > > Now we can use mkeficapsule command instead of EDK-II's script
> > > to create a signed capsule file. So update the instruction for
> > > capsule authentication.
> > >
> > > Signed-off-by: AKASHI Takahiro <takahiro.aka...@linaro.org>
> > > ---
> > > doc/develop/uefi/uefi.rst | 143 ++++++++++++++++++--------------------
> > > 1 file changed, 67 insertions(+), 76 deletions(-)
> >
> > Reviewed-by: Simon Glass <s...@chromium.org>
> >
> > thoughts below
> >
> > >
> > > diff --git a/doc/develop/uefi/uefi.rst b/doc/develop/uefi/uefi.rst
> > > index f17138f5c765..864d61734bee 100644
> > > --- a/doc/develop/uefi/uefi.rst
> > > +++ b/doc/develop/uefi/uefi.rst
> > > @@ -284,37 +284,52 @@ Support has been added for the UEFI capsule update
> > > feature which
> > > enables updating the U-Boot image using the UEFI firmware management
> > > protocol (FMP). The capsules are not passed to the firmware through
> > > the UpdateCapsule runtime service. Instead, capsule-on-disk
> > > -functionality is used for fetching the capsule from the EFI System
> > > -Partition (ESP) by placing the capsule file under the
> > > -\EFI\UpdateCapsule directory.
> > > -
> > > -The directory \EFI\UpdateCapsule is checked for capsules only within the
> > > -EFI system partition on the device specified in the active boot option
> > > -determined by reference to BootNext variable or BootOrder variable
> > > processing.
> > > -The active Boot Variable is the variable with highest priority BootNext
> > > or
> > > -within BootOrder that refers to a device found to be present. Boot
> > > variables
> > > -in BootOrder but referring to devices not present are ignored when
> > > determining
> > > -active boot variable.
> > > -Before starting a capsule update make sure your capsules are installed
> > > in the
> > > -correct ESP partition or set BootNext.
> > > +functionality is used for fetching capsules from the EFI System
> > > +Partition (ESP) by placing capsule files under the directory::
> > > +
> > > + \EFI\UpdateCapsule
> >
> > Can we use forward slashes please?
> >
> > What is a backslash, even? DOS? Windows?
>
> UEFI specification.
> In this document, all the file paths are presented with backslashes.
> (See section 8.5.5 in version 2.9)
>
> Anyhow U-Boot UEFI internally converts the path with slashes.
So do we need to use backslashes in U-Boot and in the docs? Can we use
a forward slash instead? I had hoped those days were behind us. The
backslash is used for C escapes, after all.
>
> > > +
> > > +The directory is checked for capsules only within the
> > > +EFI system partition on the device specified in the active boot option,
> > > +which is determined by BootXXXX variable in BootNext, or if not, the
> > > highest
> > > +priority one within BootOrder. Any BootXXXX variables referring to
> > > devices
> > > +not present are ignored when determining the active boot option.
> > > +
> > > +Please note that capsules will be applied in the alphabetic order of
> > > +capsule file names.
> > > +
> > > +Creating a capsule file
> > > +***********************
> > > +
> > > +A capsule file can be created by using tools/mkeficapsule.
> > > +To build this tool, enable::
> > > +
> > > + CONFIG_TOOLS_MKEFICAPSULE=y
> > > + CONFIG_TOOLS_LIBCRYPTO=y
> > > +
> > > +Run the following command::
> > > +
> > > + $ mkeficapsule \
> > > + --index 1 --instance 0 \
> > > + [--fit <FIT image> | --raw <raw image>] \
> > > + <capsule_file_name>
> > >
> > > Performing the update
> > > *********************
> > >
> > > -Since U-boot doesn't currently support SetVariable at runtime there's a
> > > Kconfig
> > > -option (CONFIG_EFI_IGNORE_OSINDICATIONS) to disable the OsIndications
> > > variable
> > > -check. If that option is enabled just copy your capsule to
> > > \EFI\UpdateCapsule.
> > > -
> > > -If that option is disabled, you'll need to set the OsIndications
> > > variable with::
> > > +Put capsule files under the directory mentioned above.
> > > +Then, following the UEFI specification, you'll need to set
> > > +the EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED
> > > +bit in OsIndications variable with::
> > >
> > > => setenv -e -nv -bs -rt -v OsIndications =0x04
> > >
> > > -Finally, the capsule update can be initiated either by rebooting the
> > > board,
> > > -which is the preferred method, or by issuing the following command::
> > > +Since U-boot doesn't currently support SetVariable at runtime, its value
> > > +won't be taken over across the reboot. If this is the case, you can skip
> > > +this feature check with the Kconfig option
> > > (CONFIG_EFI_IGNORE_OSINDICATIONS)
> > > +set.
> > >
> > > - => efidebug capsule disk-update
> > > -
> > > -**The efidebug command is should only be used during
> > > debugging/development.**
> > > +Finally, the capsule update can be initiated by rebooting the board.
> > >
> > > Enabling Capsule Authentication
> > > *******************************
> > > @@ -324,82 +339,58 @@ be updated by verifying the capsule signature. The
> > > capsule signature
> > > is computed and prepended to the capsule payload at the time of
> > > capsule generation. This signature is then verified by using the
> > > public key stored as part of the X509 certificate. This certificate is
> > > -in the form of an efi signature list (esl) file, which is embedded as
> > > -part of U-Boot.
> > > +in the form of an efi signature list (esl) file, which is embedded in
> > > +a device tree.
> > >
> > > The capsule authentication feature can be enabled through the
> > > following config, in addition to the configs listed above for capsule
> > > update::
> > >
> > > CONFIG_EFI_CAPSULE_AUTHENTICATE=y
> > > - CONFIG_EFI_CAPSULE_KEY_PATH=<path to .esl cert>
> > >
> > > The public and private keys used for the signing process are generated
> > > -and used by the steps highlighted below::
> > > +and used by the steps highlighted below.
> > >
> > > - 1. Install utility commands on your host
> > > - * OPENSSL
> > > +1. Install utility commands on your host
> > > + * openssl
> > > * efitools
> > >
> > > - 2. Create signing keys and certificate files on your host
> > > +2. Create signing keys and certificate files on your host::
> > >
> > > $ openssl req -x509 -sha256 -newkey rsa:2048 -subj /CN=CRT/ \
> > > -keyout CRT.key -out CRT.crt -nodes -days 365
> > > $ cert-to-efi-sig-list CRT.crt CRT.esl
> > >
> > > - $ openssl x509 -in CRT.crt -out CRT.cer -outform DER
> > > - $ openssl x509 -inform DER -in CRT.cer -outform PEM -out
> > > CRT.pub.pem
> > > -
> > > - $ openssl pkcs12 -export -out CRT.pfx -inkey CRT.key -in CRT.crt
> > > - $ openssl pkcs12 -in CRT.pfx -nodes -out CRT.pem
> > > -
> > > -The capsule file can be generated by using the GenerateCapsule.py
> > > -script in EDKII::
> > > -
> > > - $ ./BaseTools/BinWrappers/PosixLike/GenerateCapsule -e -o \
> > > - <capsule_file_name> --monotonic-count <val> --fw-version \
> > > - <val> --lsv <val> --guid \
> > > - e2bb9c06-70e9-4b14-97a3-5a7913176e3f --verbose \
> > > - --update-image-index <val> --signer-private-cert \
> > > - /path/to/CRT.pem --trusted-public-cert \
> > > - /path/to/CRT.pub.pem --other-public-cert /path/to/CRT.pub.pem \
> > > - <u-boot.bin>
> > > -
> > > -Place the capsule generated in the above step on the EFI System
> > > -Partition under the EFI/UpdateCapsule directory
> > > -
> > > -Testing on QEMU
> > > -***************
> > > +3. Run the following command to create and sign the capsule file::
> > >
> > > -Currently, support has been added on the QEMU ARM64 virt platform for
> > > -updating the U-Boot binary as a raw image when the platform is booted
> > > -in non-secure mode, i.e. with CONFIG_TFABOOT disabled. For this
> > > -configuration, the QEMU platform needs to be booted with
> > > -'secure=off'. The U-Boot binary placed on the first bank of the NOR
> > > -flash at offset 0x0. The U-Boot environment is placed on the second
> > > -NOR flash bank at offset 0x4000000.
> > > + $ mkeficapsule --monotonic-count 1 \
> > > + --private-key CRT.key \
> > > + --certificate CRT.crt \
> > > + --index 1 --instance 0 \
> > > + [--fit <FIT image> | --raw <raw image>] \
> > > + <capsule_file_name>
> > >
> > > -The capsule update feature is enabled with the following configuration
> > > -settings::
> > > +4. Insert the signature list into a device tree in the following format::
> > >
> > > - CONFIG_MTD=y
> > > - CONFIG_FLASH_CFI_MTD=y
> > > - CONFIG_CMD_MTDPARTS=y
> > > - CONFIG_CMD_DFU=y
> > > - CONFIG_DFU_MTD=y
> > > - CONFIG_PCI_INIT_R=y
> > > - CONFIG_EFI_CAPSULE_ON_DISK=y
> > > - CONFIG_EFI_CAPSULE_FIRMWARE_MANAGEMENT=y
> > > - CONFIG_EFI_CAPSULE_FIRMWARE=y
> > > - CONFIG_EFI_CAPSULE_FIRMWARE_RAW=y
> > > + {
> > > + signature {
> > > + capsule-key = [ <binary of signature list> ];
> > > + }
> >
> > Can you add this feature to binman? A new entry type that takes the
> > capsule key could do it. We need some way of handling this a bit
> > better.
>
> As I said in the previous version, I don't know yet if binman
> is the best place.
> Can you give me a pointer where a similar feature is implemented
> in binman, please?
See tools/binman/etype/vblock.py
>
>
> > > + ...
> > > + }
> > >
> > > -In addition, the following config needs to be disabled(QEMU ARM
> > > specific)::
> > > + You can do this manually with::
> > >
> > > - CONFIG_TFABOOT
> > > + $ dtc -@ -I dts -O dtb -o signature.dtbo signature.dts
> > > + $ fdtoverlay -i orig.dtb -o new.dtb -v signature.dtbo
> > >
> > > -The capsule file can be generated by using the tools/mkeficapsule::
> > > + where signature.dts looks like::
> > >
> > > - $ mkeficapsule --raw <u-boot.bin> --index 1 <capsule_file_name>
> > > + &{/} {
> > > + signature {
> > > + capsule-key = /incbin/("CRT.esl");
> > > + };
> > > + };
> >
> > Ick. I think your tool should just support adding the signature.
>
> # I may misunderstand your point.
>
> The whole purpose of this tool is to create a capsule file.
> Adding the signature to that file is simply an optional behavior.
> I don't see any reason that we should have those features in
> separate tools.
>
> On the other hand, step.4 mentioned above is to add public keys (x509
> certificate list or signature list in UEFI terminology) to a device tree.
> This is a separate step.
> Clear?
It just seems a pain to create a DT overlay to add the signature.
I hope Binman can help here if you don't want to put it in your tool.
I can write something if it would help.
Regards,
Simon
