4934 Commits

Author SHA1 Message Date
Lidong Chen
fadc94b919 net/dns: Prevent UAF and double free
In recv_hook(), *data->addresses is freed without being set to NULL.
Since *data->addresses can be cached in dns_cache[h].addresses, this
can lead to UAF or double free if dns_cache[h].addresses is accessed
or cleared later.

The fix sets *data->addresses to NULL after freeing to avoid dangling
pointer.

Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-24 20:05:07 +02:00
Lidong Chen
cd24e25910 net/bootp: Prevent a UAF in network interface unregister
A UAF occurs in grub_net_network_level_interface_unregister()
when inter->name is accessed after being freed in grub_cmd_bootp().
Fix it by deferring grub_free(ifaces[j].name) until after
grub_net_network_level_interface_unregister() completes.

Signed-off-by: Lidong Chen <lidong.chen@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-24 20:05:07 +02:00
Leo Sandoval
42c0997864 commands/memtools: Add lsmemregions command
Prints memory regions general information including size, number of
blocks, total free and total allocated memory per region. The reason
behind is to have a tool that shows general information about regions
and how fragmented the memory is at some particular time.

Below is an example showing how this tool before and after memory stress.

    grub> lsmemregions

    Region 0x78f6e000 (size 33554368 blocks 1048574 free 27325472 alloc 6232768)

    > stress_big_allocations
    ...

    grub> lsmemregions

    Region 0x7af8e000 (size 4032 blocks 126 free 2720 alloc 1312)
    Region 0x80c000 (size 81856 blocks 2558 free 81856 alloc 0)
    Region 0x7d165000 (size 167872 blocks 5246 free 167872 alloc 0)
    Region 0x7d0bf000 (size 655296 blocks 20478 free 655296 alloc 0)
    Region 0x7ee00000 (size 1331136 blocks 41598 free 1331136 alloc 0)
    Region 0x100000 (size 7385024 blocks 230782 free 7385024 alloc 0)
    Region 0x7af95000 (size 25382848 blocks 793214 free 25382848 alloc 0)
    Region 0x1780000 (size 2038357952 blocks 63698686 free 2077517536 alloc 5445568)

Signed-off-by: Leo Sandoval <lsandova@redhat.com>
Reviewed-by: Andrew Hamilton <adhamilt@gmail.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-24 19:39:51 +02:00
Logan Gunthorpe
8ea83c3ee2 io/zstdio: Implement zstdio decompression
Add zstd based io decompression.

Based largely on the existing xzio, implement the same features using
the zstd library already included in the project.

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-24 19:37:55 +02:00
Michael Chang
7c22c1000c fs/btrfs: Update doc link for bootloader support
The old wiki link is obsolete and no longer updated. Change it to the
current documentation.

Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:02 +02:00
Michael Chang
e4e1776613 fs/btrfs: Add environment block to reserved header area
This patch reserves space for the GRUB environment block inside the
Btrfs header. The block is placed at an offset of GRUB_ENV_BTRFS_OFFSET,
256 KiB from the start of the device, and occupies one sector. To
protect the space, overflow guard sectors are placed before and after
the reserved block.

The Btrfs header already defines regions for bootloader use. By adding
this entry, GRUB gains a fixed and safe location to store the environment
block without conflicting with other structures in the header.

Add Btrfs and its reserved area information to the fs_envblk_spec table.
With the groundworks done in previous patches, the function is now
complete and working in grub-editenv.

Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:01 +02:00
Michael Chang
3c9762b12f kern/misc: Add the "z" length modifier support
Add support for the "z" length modifier in the printf code. This allows
printing of size_t and ssize_t values using %zu, %zd and related
formats. The parser maps "z" to the correct integer width based on
sizeof(size_t).

Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
91ddada642 disk/cryptodisk: Add --hw-accel to enable hardware acceleration
The --hw-accel option has been added to cryptomount to speed up
decryption by temporarily enabling hardware-specific instruction
sets (e.g., AVX, SSE) in libgcrypt.

A new feature, "feature_gcry_hw_accel", is also introduced to mark the
availability of the new option.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
f8f68f14ae libgcrypt: Add hardware acceleration for gcry_sha512
Enable hardware acceleration for the gcry_sha512 module when building
for the x86_64 EFI target.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
70b2f5f08d libgcrypt: Add hardware acceleration for gcry_sha256
Enable hardware acceleration for the gcry_sha256 module when building
for the x86_64 EFI target.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
2158d8e8a7 libgcrypt: Declare the sha256 shaext function
There is no prototype of _gcry_sha256_transform_intel_shaext() defined
in the header or libgcrypt-grub/cipher/sha256.c, and gcc may complain
the missing-prototypes error when compiling sha256-intel-shaext.c.

Declare the prototype in sha256-intel-shaext.c to avoid the error.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
0ff5faf8cd libgcrypt: Implement _gcry_get_hw_features()
Implement _gcry_get_hw_features() and enable hardware feature detection
for x86_64.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
8423176f1f lib/hwfeatures-gcry: Enable SSE and AVX for x86_64 EFI
Implement the necessary functions to dynamically enable SSE and AVX
on x86_64 EFI systems when the hardware is capable.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
06a5b88baf lib/hwfeatures-gcry: Introduce functions to manage hardware features
This commit introduces the generic functions to manage the hardware
features in libgcrypt. These functions are stubs for future
platform-specific implementations:
  - grub_gcry_hwf_enabled() returns __gcry_use_hwf which indicates if
    the hardware features are enabled specifically by grub_enable_gcry_hwf(),
  - grub_enable_gcry_hwf() invokes the architecture specific enablement
    functions and sets __gcry_use_hwf to true,
  - grub_reset_gcry_hwf() invokes the architecture specific reset
    functions and sets __gcry_use_hwf to false.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:15:00 +02:00
Gary Lin
a122e02623 lib/pbkdf2: Optimize PBKDF2 by reusing HMAC handle
The previous PBKDF2 implementation used grub_crypto_hmac_buffer() which
allocates and frees an HMAC handle on every call. This approach caused
significant performance overhead slowing down the boot process considerably.

This commit refactors the PBKDF2 code to use the new HMAC functions
allowing the HMAC handle and its buffers to be allocated once and reused
across multiple operations. This change significantly reduces disk
unlocking time.

In a QEMU/OVMF test environment this patch reduced the time to unlock
a LUKS2 (*) partition from approximately 15 seconds to 4 seconds.

  (*) PBKDF2 SHA256 with 3454944 iterations.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:14:59 +02:00
Gary Lin
961e38b2b0 lib/crypto: Introduce new HMAC functions to reuse buffers
To enable more efficient buffer reuse for HMAC operations three new
functions have been introduced. This change prevents the need to
reallocate memory for each HMAC operation:
  - grub_crypto_hmac_reset(): reinitializes the hash contexts in the HMAC handle,
  - grub_crypto_hmac_final(): provides the final HMAC result without freeing the
    handle allowing it to be reused immediately,
  - grub_crypto_hmac_free(): deallocates the HMAC handle and its associated memory.

To further facilitate buffer reuse ctx2 is now included within the HMAC handle
struct and the initialization of ctx2 is moved to grub_crypto_hmac_init().

The intermediate hash states, ctx and ctx2, for the inner and outer padded
keys are now cached. The grub_crypto_hmac_reset() restores these cached
states for new operations which avoids redundant hashing of the keys.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:14:59 +02:00
Gary Lin
28dbe8a3b6 kern/misc: Implement faster grub_memcpy() for aligned buffers
When both "dest" and "src" are aligned, copying the data in grub_addr_t
sized chunks is more efficient than a byte-by-byte copy.

Also tweak __aeabi_memcpy(), __aeabi_memcpy4(), and __aeabi_memcpy8(),
since grub_memcpy() is not inline anymore.

Optimization for unaligned buffers was omitted to maintain code
simplicity and readability. The current chunk-copy optimization
for aligned buffers already provides a noticeable performance
improvement (*) for Argon2 keyslot decryption.

  (*) On my system, for a LUKS2 keyslot configured with a 1 GB Argon2
      memory requirement, this patch reduces the decryption time from
      22 seconds to 12 seconds.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-23 19:12:22 +02:00
Gary Lin
c1bd9fc829 tests: Integrate Argon2 tests into functional_test
Refactor the Argon2 tests to enable the module build and integrate the
tests into function_test.

Signed-off-by: Gary Lin <glin@suse.com>
Tested-By: Waldemar Brodkorb <wbx@openadk.org>
Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 14:05:50 +02:00
Gary Lin
6a525ee64f tests: Import Argon2 tests from libgcrypt
Copy the Argon2 test function, check_argon2(), from t-kdf.c in libgcrypt
to grub-core/tests/argon2_test.c.

Signed-off-by: Gary Lin <glin@suse.com>
Tested-By: Waldemar Brodkorb <wbx@openadk.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 14:01:21 +02:00
Gary Lin
6052fc2cf6 disk/luks2: Add Argon2 support
Leverage the new grub_crypto_argon2() function to add support for the
Argon2i and Argon2id KDFs in LUKS2.

Signed-off-by: Gary Lin <glin@suse.com>
Tested-By: Waldemar Brodkorb <wbx@openadk.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 13:59:12 +02:00
Gary Lin
66b8718f93 argon2: Introduce grub_crypto_argon2()
This commit introduces grub_crypto_argon2() which leverages the
_gcry_kdf_*() functions from libgcrypt to provide Argon2 support.

Due to the dependency of the _gcry_kdf_*() functions, the order of
"ldadd" entries have to be tweaked in Makefile.util.def so that the
linker can discover these functions.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Vladimir Serbinenko <phcoder@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 13:50:09 +02:00
Gary Lin
de201105d4 libgcrypt/kdf: Fix 64-bit modulus on 32-bit platforms
Use grub_divmod64() for the 64-bit modulus to prevent creation of
special division calls such as __umoddi3() and __aeabi_uldivmod() on
32-bit platforms.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 13:48:29 +02:00
Gary Lin
93544861bc libgcrypt/kdf: Remove unsupported KDFs
Clean up _gcry_kdf_*() to remove unsupported KDFs.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 13:47:50 +02:00
Gary Lin
1ff7206417 libgcrypt/kdf: Get rid of gpg_err_code_from_errno()
gpg_err_code_from_errno() requires libgcrypt_wrap/mem.c which is not in
Makefile.utilgcry.def. This commit replaces gpg_err_code_from_errno()
with GPG_ERR_* to avoid the build errors.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 13:47:25 +02:00
Gary Lin
0c06a454fc libgcrypt/kdf: Implement hash_buffers() for BLAKE2b-512
The hash_buffers() functions are disabled in GRUB by default but the
Argon2 implementation requires hash_buffers() for BLAKE2b-512.

This commit implements argon2_blake2b_512_hash_buffers() as the
replacement of _gcry_digest_spec_blake2b_512.hash_buffers().

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-21 13:46:22 +02:00
Sudhakar Kuppusamy
6b5c671d35 commands/menuentry: Fix for out of bound access
A menu entry with an empty title leads to an out-of-bounds access at
"ch = src[len - 1]", i.e., "src" is empty and "len" is zero. So, fixing
this by checking the menu entry title length and throwing an error if
the length is zero.

Signed-off-by: Sridhar Markonda <sridharm@linux.ibm.com>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:59 +02:00
Gary Lin
afddba0127 tpm2_key_protector: Support PCR capping
To prevent a sealed key from being unsealed again, a common and
straightforward method is to "cap" the key by extending the associated
PCRs. When the PCRs associated with the sealed key are extended, TPM will
be unable to unseal the key, as the PCR values required for unsealing no
longer match, effectively rendering the key unusable until the next
system boot or a state where the PCRs are reset to their expected values.

To cap a specific set of PCRs, simply append the argument '-c pcr_list'
to the tpm2_key_protector command. Upon successfully unsealing the key,
the TPM2 key protector will then invoke tpm2_protector_cap_pcrs(). This
function extends the selected PCRs with an EV_SEPARATOR event,
effectively "capping" them. Consequently, the associated key cannot be
unsealed in any subsequent attempts until these PCRs are reset to their
original, pre-capped state, typically occurring upon the next system
boot.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Gary Lin
ae7a399005 tss2: Implement grub_tcg2_cap_pcr() for emu
Since there is no system firmware for grub-emu, the TPM2_PCR_Event
command becomes the only choice to implement grub_tcg2_cap_pcr().

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Gary Lin
7b39970e90 tss2: Implement grub_tcg2_cap_pcr() for ieee1275
This commit implements grub_tcg2_cap_pcr() for ieee1275 with the
firmware function, 2hash-ext-log, to extend the target PCR with an
EV_SEPARATOR event and record the event into the TPM event log.

To avoid duplicate code, ibmvtpm_2hash_ext_log() is moved to tcg2.c
and exported as a global function.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Gary Lin
39f98e4719 tss2: Implement grub_tcg2_cap_pcr() for EFI
This commit implements grub_tcg2_cap_pcr() for EFI by using the UEFI
TCG2 protocol, HashLogExtendEvent, to extend the specified PCR with an
EV_SEPARATOR event and ensure the event will be recorded properly in the
TPM event log.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Gary Lin
d47d261ecd tss2: Introduce grub_tcg2_cap_pcr()
This commit introduces the definition of grub_tcg2_cap_pcr(), a new
function designed to enhance the security of sealed keys. Its primary
purpose is to "cap" a specific PCR by extending it with an EV_SEPARATOR
event. This action cryptographically alters the PCR value, making it
impossible to unseal any key that was previously sealed to the original
PCR state. Consequently, the sealed key remains protected against
unauthorized unsealing attempts until the associated PCRs are reset to
their initial configuration, typically occurring during a subsequent
system boot.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Gary Lin
b2549b4d34 tss2: Add TPM2_PCR_Event command
The TPM2_PCR_Event command is introduced to tss2 to allow the user to
extend a specific PCR. The related data structure and unmarshal function
are also introduced.

However, simply invoking TPM2_PCR_Event does not automatically record
the event into the TPM event log. The TPM event log is primarily
maintained by the system firmware (e.g., BIOS/UEFI). Therefore, for most
standard use cases, the recommended method for extending PCRs and
ensuring proper event logging is to utilize the system firmware
functions.

There are specific scenarios where direct use of TPM2_PCR_Event becomes
necessary. For instance, in environments lacking system firmware support
for PCR extension, such as the grub-emu, TPM2_PCR_Event serves as the
only available method to extend PCRs.

Signed-off-by: Gary Lin <glin@suse.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Thomas Zimmermann
e1b9d92a8b loader/i386/linux: Transfer EDID information to kernel
The Linux kernel's struct bootparams provides a field at offset 0x140
for storing an EDID header. Copy the video adapter's data to the field.

The edid_info field was added in 2003 (see "[FBDEV] EDID support from
OpenFirmware on PPC platoforms and from the BIOS on intel platforms."),
but only got useable in 2004 (see "[PATCH] Fix EDID_INFO in zero-page").
The boot protocol was at version 2.03 at that time.

The field was never used much, but with the recent addition of the efidrm
and vesadrm drivers to the kernel, it becomes much more useful. As with
the initial screen setup, these drivers can make use of the provided
EDID information for basic display output.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Reviewed-by: Michael Chang <mchang@suse.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Dave Vasilevsky
a8379e693b fs/hfsplus: Allow reading files created by Mac OS 9
The "permissions" field of hfsplus files is only used by Mac OS X. This
causes GRUB to skip reading files created by Mac OS 9, since their
file mode is read as unknown. Instead, assume files with zero mode
are regular files.

From Technote 1150:

  The traditional Mac OS implementation of HFS Plus does not use the
  permissions field. Files created by traditional Mac OS have the
  entire field set to 0.

Signed-off-by: Dave Vasilevsky <dave@vasilevsky.ca>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:43:58 +02:00
Srish Srinivasan
fa93f2412b kern/command,commands/extcmd: Perform explicit NULL check in both the unregister helpers
During command registration, grub_register_command_prio() returns
a 0 when there is a failure in memory allocation. In such a situation,
calls to grub_unregister_{command(), extcmd()} during command
unregistration will result in dereferencing a NULL pointer.

Perform explicit NULL check in both unregister helpers to prevent
undefined behaviour due to a NULL pointer dereference.

Signed-off-by: Srish Srinivasan <ssrish@linux.ibm.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:54 +02:00
Luca Boccassi
9a725391f1 commands/efi/tpm: Call get_active_pcr_banks() only with TCG2 1.1 or newer
The call was added in the 1.1 revision of the spec, 1.0 does
not have it, and there are some machines out there with a TPM2
and a UEFI firmware that only supports version 1.0, so the
call fails in those cases. Check the reported version before
calling get_active_pcr_banks().

See Table 4 in section 6.2 of the TCG EFI Protocol Specification:

  https://trustedcomputinggroup.org/wp-content/uploads/EFI-Protocol-Specification-rev13-160330final.pdf

Fixes: f326c5c47 (commands/bli: Set LoaderTpm2ActivePcrBanks runtime variable)

Signed-off-by: Luca Boccassi <luca.boccassi@gmail.com>
Reviewed-by: Andrew Hamilton <adhamilt@gmail.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:54 +02:00
Leo Sandoval
894241c854 kern: Include function name on debug and error print functions
With the following change, we see standard (grub_dprintf) and
error (grub_error) logs with the function name embedded (see below)
into the log which is particular useful when debugging:

  commands/efi/tpm.c:grub_tpm_measure:281:tpm: log_event, pcr = 8, size = 0xb,

Including one more field on the print log impacts the binary sizes
and in turn their respective distro packages. For Fedora rpm packages
the increase is 20k approximately.

Signed-off-by: Leo Sandoval <lsandova@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Peter Jones
75a20cc144 kern: Make grub_error() more verbose
Signed-off-by: Peter Jones <pjones@redhat.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Michael Chang
8abbafa493 net/tcp: Fix TCP port number reused on reboot
GRUB's TCP stack assigns source ports for outgoing connections starting
at 21550 and increments sequentially by 1 (e.g., 21550, 21551, ...).
While this generally works, it can lead to failures if the system
reboots rapidly and reuses the same source port too soon.

This issue was observed on powerpc-ieee1275 platforms using CAS (Client
Architecture Support) reboot. In such cases, loading the initrd over
HTTP may fail with connection timeouts. Packet captures show the failed
connections are flagged as "TCP Port Number Reused" by Wireshark.

The root cause is that GRUB reuses the same port shortly after reboot,
while the server may still be tracking the previous connection in
TIME_WAIT. This can result in the server rejecting the connection
attempt or responding with a stale ACK or RST, leading to handshake
failure.

This patch fixes the issue by introducing a time based source port
selection strategy. Instead of always starting from port 21550, GRUB now
computes an initial base port based on the current RTC time, divided
into 5 minute windows. The purpose of this time based strategy is to
ensure that GRUB avoids reusing the same source port within a 5 minute
window, thereby preventing collisions with stale server side connection
tracking that could interfere with a new TCP handshake.

A step size of 8 ensures that the same port will not be reused across
reboots unless GRUB opens more than 8 TCP connections per second on
average, something that is highly unlikely. In typical usage, a GRUB
boot cycle lasts about 15 seconds and may open fewer than 100
connections total, well below the reuse threshold. This makes the
approach robust against short reboot intervals while keeping the logic
simple and deterministic.

Signed-off-by: Michael Chang <mchang@suse.com>
Reviewed-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Sudhakar Kuppusamy
dbfa3d7d7e appended signatures: Verification tests
These tests are run through all_functional_test and test a range
of commands and behaviours.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Sudhakar Kuppusamy
7f68c71952 appended signatures: GRUB commands to manage the hashes
Introducing the following GRUB commands to manage certificate/binary
hashes.

  1. append_list_dbx:
      Show the list of distrusted certificates and binary/certificate
      hashes from the dbx list.
  2. append_add_db_hash:
      Add the trusted binary hash to the db list.
  3. append_add_dbx_hash:
      Add the distrusted certificate/binary hash to the dbx list.

Note that if signature verification (check_appended_signatures) is set to yes,
the append_add_db_hash and append_add_dbx_hash commands only accept the file
‘hash_file’ that is signed with an appended signature.

Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Tested-by: Sridhar Markonda <sridharm@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Sudhakar Kuppusamy
6cb58b1c9e appended signatures: GRUB commands to manage the certificates
Introducing the following GRUB commands to manage the certificates.

 1. append_list_db:
      Show the list of trusted certificates from the db list
 2. append_add_db_cert:
      Add the trusted certificate to the db list
 3. append_add_dbx_cert:
      Add the distrusted certificate to the dbx list
 4. append_verify:
      Verify the signed file using db list

Note that if signature verification (check_appended_signatures) is set to yes,
the append_add_db_cert and append_add_dbx_cert commands only accept the file
‘X509_certificate’ that is signed with an appended signature.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Tested-by: Sridhar Markonda <sridharm@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Sudhakar Kuppusamy
ab7b177178 appended signatures: Using db and dbx lists for signature verification
Signature verification: verify the kernel against lists of hashes that are
either in dbx or db list. If it is not in the dbx list then the trusted keys
from the db list are used to verify the signature.

Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:53 +02:00
Sudhakar Kuppusamy
97f7001e19 appended signatures: Create db and dbx lists
If secure boot is enabled with static key management mode, the trusted
certificates will be extracted from the GRUB ELF Note and added to db list.

If secure boot is enabled with dynamic key management mode, the trusted
certificates and certificate/binary hash will be extracted from the PKS
and added to db list. The distrusted certificates, certificate/binary hash
are read from the PKS and added to dbx list. Both dbx and db lists usage is
added by a subsequent patch.

Note:
- If db does not exist in the PKS storage, then read the static keys as a db
  default keys from the GRUB ELF Note and add them into the db list.
- If the certificate or the certificate hash exists in the dbx list, then do not
  add that certificate/certificate hash to the db list.

Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:52 +02:00
Sudhakar Kuppusamy
b5e872417d appended signatures: Introducing key management environment variable
Introducing the appended signature key management environment variable. It is
automatically set to either "static" or "dynamic" based on the Platform KeyStore.

"static": Enforce static key management signature verification. This is the
          default. When the GRUB is locked down, user cannot change the value
          by setting the appendedsig_key_mgmt variable back to "dynamic".

"dynamic": Enforce dynamic key management signature verification. When the GRUB
           is locked down, user cannot change the value by setting the
           appendedsig_key_mgmt variable back to "static".

Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:52 +02:00
Sudhakar Kuppusamy
76158ed1ad powerpc/ieee1275: Read the db and dbx secure boot variables
Enhancing the infrastructure to enable the Platform Keystore (PKS) feature,
which provides access to the SB_VERSION, db, and dbx secure boot variables
from PKS.

If PKS is enabled, it will read secure boot variables such as db and dbx
from PKS and extract EFI Signature List (ESL) from it. The ESLs would be
saved in the Platform Keystore buffer, and the appendedsig module would
read it later to extract the certificate's details from ESL.

In the following scenarios, static key management mode will be activated:
 1. When Secure Boot is enabled with static key management mode
 2. When SB_VERSION is unavailable but Secure Boot is enabled
 3. When PKS support is unavailable but Secure Boot is enabled

Note:

 SB_VERSION: Key Management Mode
 1 - Enable dynamic key management mode. Read the db and dbx variables from PKS,
     and use them for signature verification.
 0 - Enable static key management mode. Read keys from the GRUB ELF Note and
     use it for signature verification.

Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:46 +02:00
Sudhakar Kuppusamy
069f3614e6 appended signatures: Support verifying appended signatures
Building on the parsers and the ability to embed X.509 certificates, as well
as the existing gcrypt functionality, add a module for verifying appended
signatures.

This includes a signature verifier that requires that the Linux kernel and
GRUB modules have appended signatures for verification.

Signature verification must be enabled by setting check_appended_signatures.
If secure boot is enabled with enforce mode when the appendedsig module is
loaded, signature verification will be enabled, and trusted keys will be
extracted from the GRUB ELF Note and stored in the db and locked automatically.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:44 +02:00
Sudhakar Kuppusamy
f8e8779d8e powerpc/ieee1275: Enter lockdown based on /ibm, secure-boot
Read secure boot mode from 'ibm,secure-boot' property and if the secure boot
mode is set to 2 (enforce), enter lockdown. Else it is considered as disabled.
There are three secure boot modes. They are

0 - disabled
     No signature verification is performed. This is the default.
1 - audit
     Signature verification is performed and if signature verification fails,
     display the errors and allow the boot to continue.
2 - enforce
     Lockdown the GRUB. Signature verification is performed and if signature
     verification fails, display the errors and stop the boot.

Now, only support disabled and enforce.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:37 +02:00
Sudhakar Kuppusamy
e95c52f1f4 appended signatures: Parse X.509 certificates
This code allows us to parse:

 - X.509 certificates: at least enough to verify the signatures on the PKCS#7
   messages. We expect that the certificates embedded in GRUB will be leaf
   certificates, not CA certificates. The parser enforces this.

 - X.509 certificates support the Extended Key Usage extension and handle it by
   verifying that the certificate has a Code Signing usage.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com> # EKU support
Reported-by: Michal Suchanek <msuchanek@suse.com> # key usage issue
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:35 +02:00
Sudhakar Kuppusamy
a337549797 appended signatures: Parse PKCS#7 signed data
This code allows us to parse:

 - PKCS#7 signed data messages. Only a single signer info is supported, which
   is all that the Linux sign-file utility supports creating out-of-the-box.
   Only RSA, SHA-256 and SHA-512 are supported. Any certificate embedded in
   the PKCS#7 message will be ignored.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
Reviewed-by: Avnish Chouhan <avnish@linux.ibm.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2025-10-11 15:36:35 +02:00