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This repo is for review of requests for signing shim. To create a request for review:

  • clone this repo (preferably fork it)
  • edit the template below
  • add the shim.efi to be signed
  • add build logs
  • add any additional binaries/certificates/SHA256 hashes that may be needed
  • commit all of that
  • tag it with a tag of the form "myorg-shim-arch-YYYYMMDD"
  • push it to GitHub
  • file an issue at https://github.com/rhboot/shim-review/issues with a link to your tag
  • approval is ready when the "accepted" label is added to your issue

Note that we really only have experience with using GRUB2 or systemd-boot on Linux, so asking us to endorse anything else for signing is going to require some convincing on your part.

Hint: check the docs directory in this repo for guidance on submission and getting your shim signed.

Here's the template:

What organization or people are asking to have this signed?

Oracle Corporation

What product or service is this for?

Oracle Solaris https://www.oracle.com/solaris/solaris11/

What's the justification that this really does need to be signed for the whole world to be able to boot it?

Oracle Solaris is a widely used enterprise UNIX system with Secure Boot support.

Why are you unable to reuse shim from another distro that is already signed?

Oracle Solaris requires custom GRUB2 patches and support.

Who is the primary contact for security updates, etc.?

The security contacts need to be verified before the shim can be accepted. For subsequent requests, contact verification is only necessary if the security contacts or their PGP keys have changed since the last successful verification.

An authorized reviewer will initiate contact verification by sending each security contact a PGP-encrypted email containing random words. You will be asked to post the contents of these mails in your shim-review issue to prove ownership of the email addresses and PGP keys.

  • Name: Dave Miner
  • Position: Sr. Principal Engineer, Oracle Solaris
  • Email address: [email protected]
  • PGP key fingerprint: 7C43 24F7 2A7F 1C91 1CA9 A830 1DDC 7D07 8C45 0938

dminer.pub

(Key should be signed by the other security contacts, pushed to a keyserver like keyserver.ubuntu.com, and preferably have signatures that are reasonably well known in the Linux community.)

Who is the secondary contact for security updates, etc.?

  • Name: Alan Coopersmith
  • Position: Sr. Software Architect, Oracle Solaris
  • Email address: [email protected]
  • PGP key fingerprint: 3AB2 8523 2C46 AE43 D8E1 92F4 DAB0 F78E A6E7 E2D2

alanc.pub

(Key should be signed by the other security contacts, pushed to a keyserver like keyserver.ubuntu.com, and preferably have signatures that are reasonably well known in the Linux community.)

Were these binaries created from the 15.8 shim release tar?

Please create your shim binaries starting with the 15.8 shim release tar file: https://github.com/rhboot/shim/releases/download/15.8/shim-15.8.tar.bz2

This matches https://github.com/rhboot/shim/releases/tag/15.8 and contains the appropriate gnu-efi source.

Make sure the tarball is correct by verifying your download's checksum with the following ones:

a9452c2e6fafe4e1b87ab2e1cac9ec00  shim-15.8.tar.bz2
cdec924ca437a4509dcb178396996ddf92c11183  shim-15.8.tar.bz2
a79f0a9b89f3681ab384865b1a46ab3f79d88b11b4ca59aa040ab03fffae80a9  shim-15.8.tar.bz2
30b3390ae935121ea6fe728d8f59d37ded7b918ad81bea06e213464298b4bdabbca881b30817965bd397facc596db1ad0b8462a84c87896ce6c1204b19371cd1  shim-15.8.tar.bz2

Make sure that you've verified that your build process uses that file as a source of truth (excluding external patches) and its checksum matches. Furthermore, there's a detached signature as well - check with the public key that has the fingerprint 8107B101A432AAC9FE8E547CA348D61BC2713E9F that the tarball is authentic. Once you're sure, please confirm this here with a simple yes.

A short guide on verifying public keys and signatures should be available in the docs directory.

Yes

URL for a repo that contains the exact code which was built to result in your binary:

Hint: If you attach all the patches and modifications that are being used to your application, you can point to the URL of your application here (https://github.com/YOUR_ORGANIZATION/shim-review).

You can also point to your custom git servers, where the code is hosted.

Source rpm provided in this review tag/branch. This is identical to that used for Oracle Linux 9: shim-unsigned-x64-15.8-1.0.3.el9.src.rpm

What patches are being applied and why:

Mention all the external patches and build process modifications, which are used during your building process, that make your shim binary be the exact one that you posted as part of this application.

.spec file has two modifications vs. the SRPM

  • EFIDIR set to ORACLE
  • DISABLE_EBS_PROTECTION set to "y" as we are not using shim_lock verifier thus its protection of ExitBootServices cannot be used.

We also replace sbat.oracle.csv to identify as shim.solaris11 rather than shim.ol

Do you have the NX bit set in your shim? If so, is your entire boot stack NX-compatible and what testing have you done to ensure such compatibility?

See https://techcommunity.microsoft.com/t5/hardware-dev-center/nx-exception-for-shim-community/ba-p/3976522 for more details on the signing of shim without NX bit.

NX bit is not set

What exact implementation of Secure Boot in GRUB2 do you have? (Either Upstream GRUB2 shim_lock verifier or Downstream RHEL/Fedora/Debian/Canonical-like implementation)

Skip this, if you're not using GRUB2.

Solaris GRUB implements Solaris Verified Boot, which verifies ELF signatures on the kernel binary and modules. Its operation is generally described at https://docs.oracle.com/en/operating-systems/solaris/oracle-solaris/11.4/secure-sys-dev/using-verified-boot.html

Do you have fixes for all the following GRUB2 CVEs applied?

Skip this, if you're not using GRUB2, otherwise make sure these are present and confirm with yes.

Yes, as Solaris will be using the GRUB 2.12 release with this shim.

If shim is loading GRUB2 bootloader, and if these fixes have been applied, is the upstream global SBAT generation in your GRUB2 binary set to 4?

Skip this, if you're not using GRUB2, otherwise do you have an entry in your GRUB2 binary similar to:
grub,4,Free Software Foundation,grub,GRUB_UPSTREAM_VERSION,https://www.gnu.org/software/grub/?

No, it's grub,3. We are not building NTFS modules ( which are affected by last CVE ) into Oracle signed grub EFI binary.

Were old shims hashes provided to Microsoft for verification and to be added to future DBX updates?

Does your new chain of trust disallow booting old GRUB2 builds affected by the CVEs?

If you had no previous signed shim, say so here. Otherwise a simple yes will do.

Yes

Pre-SBAT shims revoked in dbx update

Oracle uses vendor_db with EV certificates. Pre-SBAT affected GRUB2 signing cert removed from shim, new signing EV certificate introduced in shim vendor_db. GRUB2 builds with CVE fixes signed with the new signing EV certificate.

If your boot chain of trust includes a Linux kernel:

Is upstream commit 1957a85b0032a81e6482ca4aab883643b8dae06e "efi: Restrict efivar_ssdt_load when the kernel is locked down" applied?

Is upstream commit 75b0cea7bf307f362057cc778efe89af4c615354 "ACPI: configfs: Disallow loading ACPI tables when locked down" applied?

Is upstream commit eadb2f47a3ced5c64b23b90fd2a3463f63726066 "lockdown: also lock down previous kgdb use" applied?

Hint: upstream kernels should have all these applied, but if you ship your own heavily-modified older kernel version, that is being maintained separately from upstream, this may not be the case.
If you are shipping an older kernel, double-check your sources; maybe you do not have all the patches, but ship a configuration, that does not expose the issue(s).

Solaris is not a Linux kernel, so of course the patches referenced are not applicable. However, When using Solaris Verified Boot, write access to arbitrary virtual memory by root is disallowed by Solaris device privilege policies, achieving similar effects as Linux lockdown features.

Do you build your signed kernel with additional local patches? What do they do?

Oracle Solaris is proprietary closed source

Do you use an ephemeral key for signing kernel modules?

If not, please describe how you ensure that one kernel build does not load modules built for another kernel.

The Oracle Solaris 11.4 kernel and its modules are all signed by the same RSA keypair that is managed by Oracle and used only for Oracle Solaris 11.4. Kernel modules provided by 3rd parties use a key pair belonging to that 3rd party that needs to be registered as trusted with the Oracle Solaris installation.

If you use vendor_db functionality of providing multiple certificates and/or hashes please briefly describe your certificate setup.

If there are allow-listed hashes please provide exact binaries for which hashes are created via file sharing service, available in public with anonymous access for verification.

1 EV certificate enrolled in vendor_db, used to sign mmx64, fbx64, and grub2 binaries

If you are re-using the CA certificate from your last shim binary, you will need to add the hashes of the previous GRUB2 binaries exposed to the CVEs mentioned earlier to vendor_dbx in shim. Please describe your strategy.

This ensures that your new shim+GRUB2 can no longer chainload those older GRUB2 binaries with issues.

If this is your first application or you're using a new CA certificate, please say so here.

New certificate

Is the Dockerfile in your repository the recipe for reproducing the building of your shim binary?

A reviewer should always be able to run docker build . to get the exact binary you attached in your application.

Hint: Prefer using frozen packages for your toolchain, since an update to GCC, binutils, gnu-efi may result in building a shim binary with a different checksum.

If your shim binaries can't be reproduced using the provided Dockerfile, please explain why that's the case, what the differences would be and what build environment (OS and toolchain) is being used to reproduce this build? In this case please write a detailed guide, how to setup this build environment from scratch.

Yes. shim is built on Oracle Linux with Solaris-specific certificates.

Dockerfile to reproduce build is included. Oracle Linux images are available on docker hub and container-registry.oracle.com.

$ podman build --security-opt=seccomp=unconfined -t solaris_shim15.8:shim-review .

Which files in this repo are the logs for your build?

This should include logs for creating the buildroots, applying patches, doing the build, creating the archives, etc.

x86_64-build.log

What changes were made in the distro's secure boot chain since your SHIM was last signed?

For example, signing new kernel's variants, UKI, systemd-boot, new certs, new CA, etc..

Skip this, if this is your first application for having shim signed.

Last shim signed for Oracle Solaris was shim 0.9 in 2016. We have updated GRUB2 from 1.99+patches to GRUB 2.12+ patches. New certs and CA.

What is the SHA256 hash of your final shim binary?

b098fb90bff86509aacff0e5bc197583e7e77968cc64da4d41d310fb4eab3087 shimx64.efi

How do you manage and protect the keys used in your shim?

Describe the security strategy that is used for key protection. This can range from using hardware tokens like HSMs or Smartcards, air-gapped vaults, physical safes to other good practices.

EV Certificates with private keys stored in HSM

Do you use EV certificates as embedded certificates in the shim?

A yes or no will do. There's no penalty for the latter.

Yes

Do you add a vendor-specific SBAT entry to the SBAT section in each binary that supports SBAT metadata ( GRUB2, fwupd, fwupdate, systemd-boot, systemd-stub, shim + all child shim binaries )?

Please provide the exact SBAT entries for all binaries you are booting directly through shim.

Hint: The history of SBAT and more information on how it works can be found here. That document is large, so for just some examples check out SBAT.example.md

If you are using a downstream implementation of GRUB2 (e.g. from Fedora or Debian), make sure you have their SBAT entries preserved and that you append your own (don't replace theirs) to simplify revocation.

Remember to post the entries of all the binaries. Apart from your bootloader, you may also be shipping e.g. a firmware updater, which will also have these.

Hint: run objcopy --only-section .sbat -O binary YOUR_EFI_BINARY /dev/stdout to get these entries. Paste them here. Preferably surround each listing with three backticks (```), so they render well.

grub2: sbat,1,SBAT Version,sbat,1,https://github.com/rhboot/shim/blob/main/SBAT.md grub,3,Free Software Foundation,grub,2.12,https//www.gnu.org/software/grub/ grub.solaris11,3,Oracle Solaris,grub2,2.12,mail:secalert_us.oracle.com

If shim is loading GRUB2 bootloader, which modules are built into your signed GRUB2 image?

Skip this, if you're not using GRUB2.

Hint: this is about those modules that are in the binary itself, not the .mod files in your filesystem.

video extcmd crypto sleep part_msdos part_gpt zfs zfsinfo chain boot mmap serial relocator hashsum gcry_crc cat video_fb read acpi videoinfo lsmmap terminfo iso9660 fat fshelp iorw lspci setpci memrw iorw date datetime time gettext backtrace eval file linux progress reboot efi_gop search search_label search_fs_uuid search_fs_file boot configfile echo btrfs cat chain efifwsetup efinet ext2 fat font gettext gfxmenu help gfxterm gzio halt hfsplus iso9660 jpeg keystatus loadenv linux test memdisk part_apple part_msdos part_sunpc png sleep multiboot multiboot2 mpi minicmd verified_boot

If you are using systemd-boot on arm64 or riscv, is the fix for unverified Devicetree Blob loading included?

N/A

What is the origin and full version number of your bootloader (GRUB2 or systemd-boot or other)?

GRUB 2.12 plus Oracle patches for Solaris The grub2.diff file included shows patches used for GRUB 2.12 on Solaris. The grub-2.12.tar.gz file is the patched source.

If your shim launches any other components apart from your bootloader, please provide further details on what is launched.

Hint: The most common case here will be a firmware updater like fwupd.

N/A

If your GRUB2 or systemd-boot launches any other binaries that are not the Linux kernel in SecureBoot mode, please provide further details on what is launched and how it enforces Secureboot lockdown.

Skip this, if you're not using GRUB2 or systemd-boot.

Oracle Solaris Verified Boot validates ELF signatures on the kernel and modules.

How do the launched components prevent execution of unauthenticated code?

Summarize in one or two sentences, how your secure bootchain works on higher level.

In Oracle Solaris, boot verification is performed by means of elfsign signatures or keys. At the factory, Oracle Solaris kernel modules are signed with these keys. Because of their file format, these modules are also called ELF objects. The signature is created by using the SHA-256 checksums of selected ELF records in an object file. The SHA-256 checksums are signed with a RSA-2048 private and public key pair. The public key is distributed from the /etc/certs/elfsign directory while the private key is not distributed.

Does your shim load any loaders that support loading unsigned kernels (e.g. certain GRUB2 configurations)?

No

What kernel are you using? Which patches and configuration does it include to enforce Secure Boot?

Oracle Solaris 11.4

What contributions have you made to help us review the applications of other applicants?

The reviewing process is meant to be a peer-review effort and the best way to have your application reviewed faster is to help with reviewing others. We are in most cases volunteers working on this venue in our free time, rather than being employed and paid to review the applications during our business hours.

A reasonable timeframe of waiting for a review can reach 2-3 months. Helping us is the best way to shorten this period. The more help we get, the faster and the smoother things will go.

For newcomers, the applications labeled as easy to review are recommended to start the contribution process.

Oracle is a contributor to the shim project and shim reviews.

Add any additional information you think we may need to validate this shim signing application.

None

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