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UEFI shim loader
C C++ Other

Explicitly request sysv-style ELF hash sections

We depend on there being a .hash section in the binary, and that's not
the case on distributions that default to building with gnu-style ELF
hashes. Explicitly request sysv-style hashes in order to avoid building
broken binaries.

Signed-off-by: Matthew Garrett <mjg59@coreos.com>
latest commit d7cbd4e392
Matthew Garrett authored vathpela committed
Failed to load latest commit information.
Cryptlib gcc 5.0 changes some include bits, so copy what arm does on x86.
include Make lib/ build right with the cflags it should be using...
lib Make lib/ use the right CFLAGS.
.gitignore Add ident-like blobs to shim.efi for version checking.
COPYRIGHT Add copyright file
Makefile Explicitly request sysv-style ELF hash sections
MokManager.c gcc 5.0 changes some include bits, so copy what arm does on x86.
MokVars.txt Add support for disabling db for verification
PasswordCrypt.c additional bounds-checking on section sizes
PasswordCrypt.h MokManager: support Tradition DES hash
README Replace build instructions in README with something not completely wr…
TODO Update for Josh's changes.
cert.S Add support for 32-bit ARM
crypt_blowfish.c MokManager: support blowfish-based crypt() hash
crypt_blowfish.h MokManager: support blowfish-based crypt() hash
elf_aarch64_efi.lds Add support for 64-bit ARM (AArch64)
elf_arm_efi.lds Fix typo from Ard's old tree 32-bit ARM patch.
elf_ia32_efi.lds Revert header changes
elf_ia64_efi.lds Move embedded certificates to their own section.
elf_x86_64_efi.lds Revert header changes
fallback.c Fix length of allocated buffer for boot option comparison.
make-certs Sign MokManager with a locally-generated key
netboot.c Correctly reject bad tftp addresses earlier, rather than later.
netboot.h netboot.h: fix build error on 32-bit systems
replacements.c Don't name something exit().
replacements.h Allow fallback to use the system's LoadImage/StartImage .
shim.c Don't install our protocols if we're not in secure mode.
shim.h Make SHIM_LOCK_GUID a first-class object with a symbol.
testplan.txt Another testplan error.
ucs2.h Add StrCSpn()
version.c.in Add ident-like blobs to shim.efi for version checking.
version.h Add ident-like blobs to shim.efi for version checking.

README

shim is a trivial EFI application that, when run, attempts to open and
execute another application. It will initially attempt to do this via the
standard EFI LoadImage() and StartImage() calls. If these fail (because secure
boot is enabled and the binary is not signed with an appropriate key, for
instance) it will then validate the binary against a built-in certificate. If
this succeeds and if the binary or signing key are not blacklisted then shim
will relocate and execute the binary.

shim will also install a protocol which permits the second-stage bootloader
to perform similar binary validation. This protocol has a GUID as described
in the shim.h header file and provides a single entry point. On 64-bit systems
this entry point expects to be called with SysV ABI rather than MSABI, and
so calls to it should not be wrapped.

To use shim, simply place a DER-encoded public certificate in a file such as
pub.cer and build with "make VENDOR_CERT_FILE=pub.cer".
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