Skip to content

shim: skip verification for multiple signatures once one of them is matched #700

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Draft
wants to merge 2 commits into
base: main
Choose a base branch
from
Draft

shim: skip verification for multiple signatures once one of them is matched #700

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
bd376c1
shim: immediately stop if signature is matched.
dennis-tseng99 Oct 27, 2024
4a17e58
Skip verification for multiple signatures once one of them is matched
dennis-tseng99 Oct 30, 2024
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
26 changes: 13 additions & 13 deletions shim.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -670,21 +670,21 @@ verify_buffer_authenticode (char *data, int datasize,

if (sig->Hdr.wCertificateType == WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
EFI_STATUS efi_status;

dprint(L"Attempting to verify signature %d:\n", i++);

efi_status = verify_one_signature(sig, sha256hash, sha1hash);

/*
* If we didn't get EFI_SECURITY_VIOLATION from
* checking the hashes above, then any dbx entries are
* for a certificate, not this individual binary.
*
* So don't clobber successes with security violation
* here; that just means it isn't a success.
*/
if (ret_efi_status != EFI_SUCCESS)
ret_efi_status = efi_status;
if (ret_efi_status != EFI_SUCCESS) {
efi_status = verify_one_signature(sig, sha256hash, sha1hash);
/*
* If we didn't get EFI_SECURITY_VIOLATION from
* checking the hashes above, then any dbx entries are
* for a certificate, not this individual binary.
*
* So don't clobber successes with security violation
* here; that just means it isn't a success.
*/
ret_efi_status = efi_status;
}
} else {
perror(L"Unsupported certificate type %x\n",
sig->Hdr.wCertificateType);
Expand Down
Loading