The license statements in our source files were getting to be a giant
mess, and mostly they all just say the same thing. I've switched most
of it to SPDX labels, but left copyright statements in place (where they
were not obviously incorrect copy-paste jobs that I did...).
If there's some change here you don't think is valid, let me know and
we can fix it up together.
Signed-off-by: Peter Jones <pjones@redhat.com>
Potential new signing strategies ( for example signing grub, fwupdate
and vmlinuz with separate certificates ) require shim to support a
vendor provided bundle of trusted certificates and hashes, which allows
shim to trust EFI binaries matching either certificate by signature or
hash in the vendor_db. Functionality is similar to vendor_dbx.
This also improves the mirroring quite a bit.
Upstream: pr#206
This moves them both to be computed at runtime from a pointer+offset
rather than just a pointer, so that their real address can be entirely
derived from the section they're in.
This means you can replace the whole .vendor_cert section with a new one
with certs that don't have the same size.
With this change, the embedded certificate and dbx lists (vendor_cert,
vendor_cert_size, vendor_dbx, and vendor_dbx_size) wind up being in a
section named .vendor_cert, and so will look something like:
------
fenchurch:~/devel/github.com/shim$ objdump -h shim.efi
shim.efi: file format pei-x86-64
Sections:
Idx Name Size VMA LMA File off Algn
0 .eh_frame 000174a8 0000000000005000 0000000000005000 00000400 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
1 .text 000aa7e1 000000000001d000 000000000001d000 00017a00 2**4
CONTENTS, ALLOC, LOAD, READONLY, CODE
2 .reloc 0000000a 00000000000c8000 00000000000c8000 000c2200 2**0
CONTENTS, ALLOC, LOAD, READONLY, DATA
3 .data 00031228 00000000000c9000 00000000000c9000 000c2400 2**5
CONTENTS, ALLOC, LOAD, DATA
4 .vendor_cert 00000375 00000000000fb000 00000000000fb000 000f3800 2**0
CONTENTS, READONLY
5 .dynamic 000000f0 00000000000fc000 00000000000fc000 000f3c00 2**3
CONTENTS, ALLOC, LOAD, DATA
6 .rela 0002afa8 00000000000fd000 00000000000fd000 000f3e00 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
7 .dynsym 0000f1f8 0000000000128000 0000000000128000 0011ee00 2**3
CONTENTS, ALLOC, LOAD, READONLY, DATA
------
This simplifies a security audit, because it means that different
versions of shim with substantially the same code with different keys
will be more easily comperable, and therefore logic differences may be
more easily identified.
This also means that if there's a trusted build you want to use, you can
remove the certificates, implant new ones, and have it signed, and the
code sections won't change.
Signed-off-by: Peter Jones <pjones@redhat.com>
