tpm2_unseal() returns -EUCLEAN specifically when a PCR kept being
extended while unsealing, but the unseal callers no longer catch it
via ERRNO_IS_NEG_TPM2_UNSEAL_BAD_PCR() and would fall back to the
generic "Failed to unseal secret using TPM2" message.
Give it a message of its own instead, so that the log points at the
actual cause instead of suggesting the system was tampered with.
Signed-off-by: Alberto Planas <aplanas@suse.com>
(cherry picked from commit 941db14b8e)
Like the command-level CommandDescription.argspec, a verb's argspec is now
a nulstr, so that a verb may declare multiple alternative usage lines. The
verbs help table renders one synopsis line per nulstr entry in the
synopsis cell.
All verb argument specifications must gain an explicit NUL suffix. This
is a lot of churn, but I think this needs to be done. For now, there'll
be only one user of the new functionality (i.e. a verb with more than
one argspec), but I think we'll eventually want to use this in other
places too.
Almost all programs are simple and have only a single command. When
printing options, let's just use the first COMMAND block found by default.
This means we can drop the explicit program-name argument and reduce
copy&paste boilerplate.
Measure the volume key and unlock keyslot through io.systemd.PCRExtend
instead of driving the TPM directly via tpm2-util, matching how the
verity and imds measurements already work.
Bank selection and the TPM context now live entirely in
systemd-pcrextend. As a result the tpm2-measure-bank= crypttab option
can no longer be honored per volume and is now a deprecated no-op.
Signed-off-by: Paul Meyer <katexochen0@gmail.com>
NV indexes created in the storage hierarchy can be undefined and
redefined with TPM owner auth. Because of this, NvPCRs need some way
to prevent them from being redfined in a way that allows spoof
measurements to be replayed.
The current approach requires knowledge of a secret ("anchor secret")
in order to derive the initial NvPCR measurement and to derive a
measurement to an existing PCR (9). The credential is protected by the
TPM with a PCR policy. Without access to the credential, it's not
possible to replay measurements to a newly defined NvPCR without
breaking the binding with the measurement in PCR 9. However, this
approach has a couple of issues:
- The credential is currently only protected by PCR11. As it's not
protected by the rest of the boot chain, it's possible to boot other
operating systems in order to replay the PCR11 measurements and
recover the secret. Note that as the NvPCR anchoring happens in early
boot, the credential is stored in the ESP.
- Someone with privileged access to a system can just create a new
credential containing a known secret and store this in /var/lib and
the ESP. The NvPCRs are anchored with this known secret on subsequent
boots, and therefore the measurements can no longer be trusted.
Imagine the scenario where privileged access is theoretically possible
as a result of some vulnerability. After upgrading the system to fix
this vulnerability, the system should be able to attest that it is
now in a good state. However, if an adversary were able to use their
priviliges to replace the credential, they are able to obtain
persistence and the NvPCR measurements are no longer trustworthy.
This PR changes things to take a different approach. Instead of
requiring knowledge of a secret, the NvPCRs are now created in a way
that requires a policy to be satisfied for writing. The write policy has
2 branches:
- TPM2_PolicyNvWritten(true), which can be satisified without any
further authorization if the NvPCR has already been extended.
- TPM2_PolicyAuthorize(pcrPubKey, SHA256("nvpcr-init")) which can be
satisfied with a signed PCR policy, and must be used to perform the
initial extend to a NvPCR.
The intention here is that the signed PCR policy that can be used to
authorize the initial extend to the NvPCR can only be satisfied during
early boot. During later boot phases, this signed PCR policy must not be
valid. This means that if a NvPCR is undefined and redefined, it won't
be possible to satisfy its write policy in order to able to perform the
initial extend.
In order to anchor the NvPCRs and prevent them from being undefined and
then redefined with a different policy that does allow them to be
extended, the names of the NvPCRs are measured to PCR9. Verifiers must
check that the names of attested NvPCRs match the measurements in PCR9.
This uses the PCR signing key from the currently booted UKI to create
the NvPCRs. If this changes between boots, then tpm2-setup automatically
recreates new NvPCRs with an updated write policy to reflect this. I've
tried to be careful to not undefine arbitrary NV indexes in this case,
so it checks that the existing NV index looks like a NvPCR (ie, it has
the expected attributes) before undefining it.
I did originally try to preserve the old behaviour for existing systems,
but it makes things a lot more complicated. As the new implementation
already creates new NvPCRs when the PCR signing key changes, I ended up
just automatically upgrading the old NvPCRs as well. Again, I check here
that any existing NV index looks like an old style NvPCR (ie, it has the
expected attributes) before undefining it.
I did notice that the initial NvPCR measurement isn't going into the
log. I don't know if that was an intentional choice, but I've preserved
that behaviour in this PR.
This also adds a new option to ukify (--sign-initrd-pcrs) which creates
signed policies (one per PCR bank) that can only be satisfied from the
initrd. These policies are used for initializing the NvPCRs, but can also
be used for protecting TPM2 keyslots enrolled with systemd-cryptenroll
(by using the --tpm2-public-key-policyref=initrd option).
There is one outstanding issue. The NvPCR definitions support different
algorithms, but the use of PolicyAuthorize means that they can only support
SHA-256 for now. This is because the signed policy algorithm must match
the name algorithm, and some additional work is required to support
signed PCR policies for algorithms other than SHA256. I've left a note in
tpm2_nvpcr_initialize that details what's required, and I'll take a look
at that in a subsequent PR.
password-cache= tracks both the cache mode and whether the option was
configured explicitly. The parser set arg_password_cache_set before
validating the value, so an invalid value was logged as ignored but
still blocked the PKCS#11 default no-cache policy.
Only mark password-cache= as configured after accepting read-only or a
valid boolean.
Repro:
build/systemd-cryptsetup attach sdscan /dev/null - \
pkcs11-uri=auto,password-cache=bogus
Before: warned ignored, then failed with the PKCS#11 cache error.
After: warned ignored, then continued to the device check.
Follow-up for: fd8ed7f26b
size= is specified in bits, but arg_key_size stores bytes after
parsing. The parser used arg_key_size as temporary storage before
validation. When the value was not divisible by 8, the warning said
the option was ignored, but the invalid bit count remained.
Parse into a local variable and update arg_key_size only after
validation.
Repro:
build/systemd-cryptsetup attach sdscan /tmp/plain.img /tmp/key \
plain,size=7
Before: warned ignored, then used key size 56 bits.
After: warned ignored, then kept the default key size 256 bits.
Follow-up for: 6131a78b4d
Since 4c0d8d9673, most dlopen notes are
set at the beginning of the executables. Let's manage all dlopen notes
there, rather than setting them where dlopen is called.
Note that the only exceptions are the LIBBPF_NOTE for networkd and
nsresource. Since dlopen_bpf() is wrapped in an `#if` guard, the notes
are instead set within the corresponding functionality.
As a result, the DLOPEN_FOO() wrapper macros are no longer needed and
can be dropped completely.
Both callers of tpm2_nvpcr_extend_bytes() duplicate the same dance: on
-ENETDOWN, i.e. when the NvPCR isn't anchored yet because
systemd-tpm2-setup hasn't run, they acquire the anchor secret,
initialize the NvPCR, and extend again. Move this into
tpm2_nvpcr_extend_bytes() itself. The only caller-specific bit, whether
the anchor secret shall be synced to /var, is passed in as a parameter.
Signed-off-by: Paul Meyer <katexochen0@gmail.com>
tpm2-util.h includes crypto-util.h, which requires OpenSSL compiler
flags when HAVE_OPENSSL is defined. Add libopenssl_cflags to every
build target that uses tpm2_cflags but was missing the transitive
OpenSSL dependency.
The current TPM2 PIN mode is flawed as a compromised TPM directly exposes
the sealed secret which is the LUKS volume key itself (#27502 and #37386).
Goal: add Argon2id-based PIN hardening to TPM2 enrollment, making
the TPM a second factor rather than a single point of failure:
1. Password + salt -> Argon2id -> 512-bit key split into Key1 + Key2
2. Key2 (base64-encoded) is used as the PIN to seal a random secret
in the TPM
3. Key1 + unsealed secret -> HKDF-SHA256 -> final LUKS volume key
This implementation ensures that if the TPM is compromised, an attacker
still needs the password to derive Key1 and combine it with the unsealed
secret.
The --tpm2-with-pin= option now accepts three values:
- false (no PIN used)
- true (PIN hardened with Argon2id - default)
- "direct" (legacy PIN without Argon2id for backward compatibility)
Argon2id parameters are customizable via:
--tpm2-argon2id-memory=
--tpm2-argon2id-iterations=
--tpm2-argon2id-parallelism=
--tpm2-argon2id-iter-time=
These default to a function of available CPUs and physical memory, with
a benchmark that scales iterations to the target time (default: 2s) and
falls back to ARGON2ID_PARAMETERS_DEFAULT (64 MiB, 8 iter, 4 lanes) when
auto detection fails.
Also if the runtime OpenSSL lacks Argon2id support (< 3.2), the feature
silently falls back to direct PIN mode with a warning.
Added includes:
- src/cryptenroll/cryptenroll.c: cpu-set-util.h, limits-util.h, time-util.h
for Argon2id benchmark auto-tuning (cpus_online, physical_memory_scale,
now/usec_t)
- src/cryptenroll/cryptenroll-tpm2.c: crypto-util.h for Argon2IdParameters
struct in load_volume_key_tpm2()
- src/shared/tpm2-util.h: crypto-util.h for Argon2IdParameters in
tpm2_make_luks2_json() API
- src/shared/tpm2-util.c: limits-util.h, tpm2-util.h for physical_memory() validation
of Argon2id memory cost and function prototypes
- src/cryptsetup/cryptsetup-tokens/luks2-tpm2.c: crypto-util.h for
kdf_argon2id_derive()/kdf_hkdf_sha256() on the token unlock path
Previously, when a library was dynamically loaded via a helper function
inside libsystemd-shared.so, the resulting dlopen ELF note was not
propagated to the invoking executable's ELF metadata.
This commit explicitly annotates each executable with the relevant
dlopen ELF notes for any optional dependencies it might potentially
load. This ensures that package managers and build systems can properly
discover runtime dependencies that are triggered indirectly.
This also switches all these notes to be defined via SD_ELF_NOTE_DLOPEN_ANCHORED().
Consequently, any notes added within unreachable or unused functions will be
automatically garbage-collected by the linker (--gc-sections) instead of
bloating the final binary.
E.g. unused p11-kit library dependency is now dropped from
systemd-repart.standalone binary.
Before:
```
$ systemd-analyze dlopen-metadata build/systemd-repart.standalone
FEATURE DESCRIPTION SONAME PRIORITY
cryptsetup Support for disk encryption, integrity, and authentication libcryptsetup.so.12 recommended
blkid Support for block device identification libblkid.so.1 required
libcrypto Support for cryptographic operations libcrypto.so.4 libcrypto.so.3 recommended
mount Support for mount enumeration libmount.so.1 required
fdisk Support for reading and writing partition tables libfdisk.so.1 required
blkid Support for block device identification libblkid.so.1 recommended
libcrypto Support for cryptographic operations libcrypto.so.4 libcrypto.so.3 suggested
cryptsetup Support for disk encryption, integrity, and authentication libcryptsetup.so.12 suggested
fdisk Support for reading and writing partition tables libfdisk.so.1 suggested
idn Support for internationalized domain names libidn2.so.0 suggested
mount Support for mount enumeration libmount.so.1 recommended
selinux Support for SELinux libselinux.so.1 recommended
tpm Support for TPM libtss2-esys.so.0 suggested
tpm Support for TPM libtss2-rc.so.0 suggested
tpm Support for TPM libtss2-mu.so.0 suggested
tpm Support for TPM libtss2-tcti-device.so.0 suggested
p11-kit Support for PKCS11 hardware tokens libp11-kit.so.0 suggested
```
After:
```
$ systemd-analyze dlopen-metadata build/systemd-repart.standalone
FEATURE DESCRIPTION SONAME PRIORITY
cryptsetup Support for disk encryption, integrity, and authentication libcryptsetup.so.12 recommended
blkid Support for block device identification libblkid.so.1 required
libcrypto Support for cryptographic operations libcrypto.so.4 libcrypto.so.3 recommended
mount Support for mount enumeration libmount.so.1 required
fdisk Support for reading and writing partition tables libfdisk.so.1 required
blkid Support for block device identification libblkid.so.1 recommended
libcrypto Support for cryptographic operations libcrypto.so.4 libcrypto.so.3 suggested
cryptsetup Support for disk encryption, integrity, and authentication libcryptsetup.so.12 suggested
fdisk Support for reading and writing partition tables libfdisk.so.1 suggested
mount Support for mount enumeration libmount.so.1 recommended
selinux Support for SELinux libselinux.so.1 recommended
tpm Support for TPM libtss2-esys.so.0 suggested
tpm Support for TPM libtss2-rc.so.0 suggested
tpm Support for TPM libtss2-mu.so.0 suggested
tpm Support for TPM libtss2-tcti-device.so.0 suggested
```
Extend the module building logic to automatically generate '.standalone'
variants for non-NSS/PAM shared modules (such as cryptsetup tokens).
Like standalone executables, these are not built by default to keep
the base build time unaffected, but can be built explicitly on demand
via `ninja <module_name>.standalone`.
To be able to continue trying other tokens to unlock a disk the missing
NV index case was mapped to EREMOTE (foreign TPM) which was ok because
this mostly happens when trying to unlock on another system. Still it
might be useful to deal with NV index errors differently.
Give it its own EADDRNOTAVAIL error and handle it at all call sites.
The plugin already continues on parsing errors but the fallback path
not. The plugin swallows ENOMEM as well which is too much, though.
Continue on JSON parsing errors by mapping them to EUCLEAN in
cryptsetup_get_token_as_json and handle that in any call site, not just
the TPM fallback path but also others.
When we iterate over tokens we should not print mismatches as errors
but rather warnings. At the end there is still a summary with the
notice level (gated by found_some) which the user can relate to the
warnings.
Currently libcryptsetup's look treats ENOANO special because it's used
to signal PIN requirement. But the bad PCR set can also contain ENOANO
for a mismatch from a PolicyOR branch.
To continue iterating, remap the bad PCR set to EPERM early. This would
in theory also allow us to simplify the matching for the iteration
condition but we leave this as is for now to prevent a future
regression.
When we have many LUKS slots and not all are for our TPM, we can get an
NV index error when it's missing or has wrong content.
Instead of fully erroring out, map these encounters to EREMOTE like we
do for a foreign TPM key.
When we enroll two UKIs with different PCR pub keys into one LUKS slot/
token each, then we can encounter the wrong one and should not give up
but continue iterating instead of requiring the passphrase. Similarly,
a pcrlock token might be for another UKI and we should continue the
search. Same for a token that is meant for another TPM (e.g., external
storage). While this is mainly about cryptsetup's automatic unlocking
from the initrd, it also matters for usage in the system, e.g., for
other storage and when cryptenroll should unlock using the TPM.
There are two code paths, one is the libcryptsetup plugin and the other
is the fallback when that's not available.
To let the libcryptsetup loop continue to iterate, remap the above
error conditions to EPERM. For the fallback path check all of them (no
remapping) and continue iteration. For better log output, include the
token ID to be able understand which token fails.
When we enroll two UKIs with different PCR pub keys into one LUKS slot/
token each, then we can encounter the wrong one and should report it
with a clearer error than the generic "Failed to unseal secret using
TPM2".
So when we don't have the right signature, report this as separate
error.
This makes each `foo_cflags` dependency define a `SYSTEMD_CFLAGS_MARKER_FOO`
macro, and checks if the macro is set when headers provided by external
libraries are included.
With this, we can fail fast at compile time if necessary `_cflags`
dependencies are omitted in meson.build. Missing dependencies found by this
mechanism have been added across the tree.
systemd-measure can produce multiple signed policies for different
phases. However, a policy for a TPM resource that includes these signed
policies can currently be satisfied by any policy that is signed
with the same key.
It can be desirable to bind a resource's policy to one or more
specific phases. One way to do this could be to sign policies for
different phases or phase combinations with different keys. Another
approach is to limit the scope of signed policies using a policy
reference.
Using a policy reference works because:
- The reference is included along with the approved policy digest in the
digest that is signed.
- The reference argument is included in the authorization policy for a
resource via the TPM2_PolicyAuthorize assertion.
- During execution of the TPM2_PolicyAuthorize assertion, the TPM checks
that the session's current policy digest is the approved policy digest,
computes a digest from the approved policy digest and the supplied policy
reference, and checks that the resulting digest is the one that was
verified by TPM2_VerifySignature (via the returned ticket).
This adds a new --policyref argument to systemd-measure which binds all
of the signed policies to the specified policy reference. I did consider
making this more intelligent by auto-generating policy references for each
phase, but this approach provides the most flexibility for now. By making
use of the existing --append argument, a signer can produce multiple
signed policies with the same key that are bound to any individual phases
or combinations of phases.
The policy reference is a string without the NULL terminator. It is
supplied to the TPM via the TPM2B_NONCE type, which has a maximum size
equivalent to the size of the largest digest supported by the TPM. As
the signer doesn't know the capabilities of the target TPM,
systemd-measure limits the size of the policy reference to 32 bytes, to
fit within the size of a SHA256 digest.
This also includes the corresponding changes to systemd-cryptenroll and
systemd-repart (to add an equivalent --tpm2-public-key-policyref argument
so that the policy can be bound to the desired corresponding phase, and to
ensure that the policy reference is included in the LUKS2 token metadata),
and systemd-cryptsetup (to handle the policy reference stored in the LUKS2
token metadata).
This doesn't include policy reference support for credentials yet
because it requires a change to the credential headers.
A single incorrect password attempt from the user would be tried
twice, because the first failed try would think it was the
try_discover_key method that failed, and would invalidate that instead
of the actual failed password. This resulted in the user being
prompted one fewer time than they should be.
Fixes#38495
keyfile-erase only erases a key file explicitly configured in the third
field of crypttab. Key files automatically discovered in
/etc/cryptsetup-keys.d/ and /run/cryptsetup-keys.d/ are considered shared
resources not owned by an individual volume, and are never erased. Make
this explicit in the documentation and add a code comment clarifying the
intent.
Fixes: https://github.com/systemd/systemd/issues/41127
Co-developed-by: Claude Opus 4.8 <noreply@anthropic.com>
Switch the executable-owned call sites from the plain dlopen_<lib>()
helpers to the new DLOPEN_<LIB>() macros, so that each binary that loads
an optional library at runtime now carries its own .note.dlopen note
instead of relying solely on libsystemd-shared. Each call site passes a
priority reflecting whether it hard-depends on the library (required) or
degrades gracefully without it (recommended).
Co-developed-by: Claude Opus 4.8 <noreply@anthropic.com>
RSA PKCS#1 v1.5 is vulnerable to Bleichenbacher-style padding oracle
attacks, albeit very difficult and unlikely to actually happen in the
real world. Still for hardedning, switch new enrollments to RSA-OAEP,
with SHA-256 preferred and SHA-1 as fallback (probed at enrollment time,
since e.g. SoftHSM only accepts SHA-1, and older token might as well).
The actual padding scheme used to wrap a given key is recorded as a new
optional 'pkcs11-padding' / 'padding' field in the LUKS2 token JSON and
the homed user record. Decryption defaults to PKCS#1 v1.5 when absent so
existing enrollments keep working.
This avoids having to subpackage the tokens separately. If they link directly
against libcryptsetup, package manager will automatically add a dependency on
libcryptsetup to the package containing the tokens. With this change, the tokens
can ship in the main systemd package without necessarily pulling in libcryptsetup.
It also makes things more consistent. Once we also do the same for pam, any direct
linking will be limited to just libc, which for example simplifies writing tests for
ensuring we don't link unnecessarily as we don't have to add exceptions for the
cryptsetup tokens.
This actually drops the dependency on cryptsetup-libs for the fedora/centos/opensuse
systemd-udev package so install it explicitly in the initrd now to keep the tests
working.
For libc syscall wrappers (pidfd_open, fsopen, openat2, etc.) we previously
gated the calls behind build-time HAVE_* checks. Replace these with shim
functions in src/libc/ that fall back to the raw syscall at runtime when the
loaded glibc lacks the symbol. The infrastructure lives in src/libc/libc-shim.h:
DEFINE_SYSCALL_SHIM falls back to a direct syscall, DEFINE_LIBC_SHIM returns
ENOSYS (for posix_spawn-family helpers that have no corresponding syscall), and
DEFINE_LIBC_ERRNO_SHIM sets errno=ENOSYS and returns -1 (for read/write-style
helpers). The weak reference to the libc symbol is bound via __asm__(\"name\")
rename so the bare libc identifier never appears as a C token — this avoids
both #undef boilerplate against override-header redirects and the resulting
-Wredundant-decls warning. Drop the corresponding cc.has_function() loop from
meson.build.
For optional libraries (libcryptsetup, libdw, libarchive), drop the per-symbol
HAVE_* checks. Always declare the prototypes, suppressing the redundant-decl
warnings via DISABLE_WARNING_REDUNDANT_DECLS and NOLINT, and resolve the symbols
after the main dlopen via a new DLSYM_OPTIONAL() helper that only assigns on
success. libcryptsetup's crypt_set_keyring_to_link / crypt_token_set_external_path
and libarchive's *_is_set wrappers use fallback functions as their pointer
initializers (returning -ENOSYS and 0 respectively), so call sites can invoke
the symbol unconditionally and just check for -ENOSYS where the \"not supported\"
distinction matters.
The same shim treatment applies to pidfd_spawn / posix_spawnattr_setcgroup_np
(src/libc/spawn.c) and epoll_pwait2 (src/libc/epoll.c), with corresponding
override headers in src/include/override/spawn.h and
src/include/override/sys/epoll.h. posix_spawn_wrapper() in process-util.c and
epoll_wait_usec() in sd-event.c now detect ENOSYS in the return value instead
of checking the function pointer, falling back to plain posix_spawn() and
epoll_wait() respectively. coredump-config and coredump-submit get a
dlopen_dw_has_dwfl_set_sysroot() helper. The kexec arch gate now uses
defined(__NR_kexec_file_load) directly; pidfd.h uses __has_include_next() to
decide whether to pull in glibc's header.
This lets binaries built against newer glibc / libcryptsetup / libdw /
libarchive headers still load and run on older targets where these symbols are
absent.
When a keyfile is passed with tpm2-device=, e.g.,
systemd-cryptsetup attach test_data /vol /my-pass tpm2-device=auto
the logic in attach_luks_or_plain_or_bitlk_by_tpm2() tries to process it as a
TPM blob first. This did not work properly because it passes n_blobs=1 to
acquire_tpm2_key(), and the key_file is only read when n_blobs == 0. As a
result, the code ends up calling tpm2_unseal(..., blobs=NULL, n_blobs=1, ...).
Before commit 5c6aad9 ("cryptsetup-tokens: Print tpm2-primary-alg: only when it
is known"), the segfault was not observed because tpm2_unseal() was bailing out
early when primary_alg == 0. However, after that change, it attempts to process
the blob (which is NULL) and crashes.
Fix this logic by passing n_blobs=0 to acquire_tpm2_key() so that it actually
reads the key_file. Additionally, assert 'blobs' in tpm2_unseal() as a
safeguard.
Fixes#41867
I am really not a fan of full code lines passed to macros as parameters.
Let's get rid of the 3rd parameter of FOREACH_OPTION() hence:
1. Let's return errors just as a regular value (though a negative one),
that can be handled via a OPTION_ERROR case statement for the switch.
This normalizes handling of the error, just like any other event
returned by the option parser.
2. In order to avoid exploding the amount of boilerplate in each use
(that just propagates the error on OPTION_ERROR), let's then
introduce an explicit FOREACH_OPTION_OR_RETURN(), that returns from
the calling function on its own (and makes that clear in the name).
Together this cleans up, normalizes the logic and shortens the code.
It was requested to make the 'c', 'opt', and 'arg' params the same, i.e.
defined through the FOREACH_OPTION macro. But we can't do that easily,
because 'c' was defined in the for loop definition, and we can only
define variables of the same type in that way. Also, in some cases we
need only 'c', in other cases with need 'c' and 'arg, in some cases 'c'
and 'opt', and in other cases all three. We'd need to either
conditionalize or mark those variables with _unused_ to deal with
compiler warnings. But a different approach works quite nicely: add
state.opt and state.arg to show the current option and it's argument.
(The short names are picked on purpose to reduce verbosity since those
are used a lot.)
Until now OpenSSL was linked into every binary and library that needed
cryptography, pulling libcrypto (and, for resolved, libssl) into the
address space of services that never touch them at runtime. This commit
moves all OpenSSL usage behind the same dlopen helper pattern that we
already use for other optional libraries (libpam, libseccomp, libxz, …)
so libcrypto/libssl are only loaded on demand.
The bulk of the work lives in src/shared/crypto-util.{c,h} (libcrypto)
and src/shared/ssl-util.{c,h} (libssl), which replace the previous
src/shared/openssl-util.{c,h}:
- crypto-util.{c,h} declares every libcrypto function we call via
DLSYM_PROTOTYPE() and resolves them inside dlopen_libcrypto().
- ssl-util.{c,h} holds the libssl-specific DLSYM_PROTOTYPEs,
dlopen_libssl(), and the SSL_freep cleanup helper, so translation
units that only need libcrypto do not pull in libssl declarations.
- Callers refer to the symbols through sym_* aliases rather than the
original names.
- Convenience macros that used to be provided by the OpenSSL headers
(OPENSSL_free, BN_num_bytes, the sk_TYPE_* helpers, …) are
reimplemented as sym_* wrappers so no code path needs to fall back
to the linker-resolved symbols.
- All _cleanup_ helpers are redefined in terms of the sym_* variants
(EVP_PKEY_freep, X509_freep, BIO_freep, …) so cleanup attributes
keep working without pulling in libcrypto symbols at link time.
- The public crypto-util.c entry points (openssl_pubkey_from_pem,
openssl_digest_many, openssl_hmac_many, openssl_cipher_many,
kdf_ss_derive, kdf_kb_hmac_derive, rsa_* / ecc_* helpers,
pubkey_fingerprint, digest_and_sign, pkcs7_new, x509_fingerprint,
openssl_extract_public_key, pkey_generate_volume_keys, the load_*
helpers, …) now call dlopen_libcrypto() at entry before touching any
sym_* pointer.
The call sites across the tree have been converted to call
dlopen_libcrypto()/dlopen_libssl() at the appropriate entry point
before their first sym_* use, and to use sym_* variants throughout:
- bootctl, sbsign, measure, pcrlock, pcrextend, tpm2-setup, repart,
cryptsetup, cryptenroll, homectl, homed, homework, keyutil,
sysupdate, creds, import, dissect-image, pe-binary, pkcs11-util,
pkcs7-util, tpm2-util, creds-util. resolved additionally dlopens
libssl for DoT.
The meson build files are updated to depend on libopenssl_cflags (a
new partial dependency that exposes include paths and compile flags
only, not the linker flags) instead of libopenssl for every target that
previously linked against OpenSSL. Nothing links against libcrypto or
libssl directly anymore.
A new src/sbsign/authenticode.c hosts the Authenticode ASN.1 type
definitions that used to live inline in sbsign.c. The OpenSSL
ASN1_SEQUENCE / ASN1_CHOICE / IMPLEMENT_ASN1_FUNCTIONS macros expand to
code that references libcrypto symbols directly, so to keep this
translation unit unlinked from libcrypto we redirect ASN1_item_* to
the sym_* variants via #define and wrap the ASN1_*_it() getters (which
appear as constant function pointers in static initializers) in small
trampoline functions that forward to the sym_* pointers at runtime.
test-dlopen-so gains assertions for dlopen_libcrypto and dlopen_libssl
so the dlopen contract is exercised in CI, and the openssl-specific
test was renamed from test-openssl.c to test-crypto-util.c to match
the new header naming.
Convert systemd-cryptsetup, systemd-cryptenroll, systemd-veritysetup
and systemd-integritysetup to go through the existing dlopen wrapper
for libcryptsetup instead of linking the library directly. Each binary
calls dlopen_cryptsetup() at the start of its run() and uses the sym_*
variants for every libcryptsetup entry point.
Extend cryptsetup-util.{h,c} to cover the libcryptsetup symbols that
these binaries use and that the wrapper was missing:
crypt_activate_by_token_pin, crypt_deactivate, crypt_init_data_device,
crypt_keyslot_status, crypt_set_keyring_to_link (conditional on
HAVE_CRYPT_SET_KEYRING_TO_LINK), crypt_status and
crypt_token_external_path.
With no direct callers of crypt_free() left, drop the non-sym
crypt_freep cleanup variant and rename sym_crypt_freep back to
crypt_freep via DEFINE_TRIVIAL_CLEANUP_FUNC_FULL_RENAME, matching the
naming convention used by other dlopen wrappers (acl_freep,
xkb_context_unrefp, ...). Update the remaining users in src/shared,
src/repart, src/home and src/growfs to the new name.
The four affected meson targets switch from libcryptsetup to
libcryptsetup_cflags so they no longer record a DT_NEEDED entry for
libcryptsetup.so.12.
The synopisis is moved from the header to the a new section:
-systemd-cryptsetup attach VOLUME SOURCE-DEVICE [KEY-FILE] [CONFIG]
-systemd-cryptsetup detach VOLUME
+systemd-cryptsetup [OPTIONS...] {COMMAND} ...
Attach or detach an encrypted block device.
+Commands:
+ attach VOLUME SOURCE-DEVICE [KEY-FILE] [CONFIG] Attach an encrypted block
+ device
+ detach VOLUME Detach an encrypted block
+ device
+
+Options:
I think that's OK… With the autogenerated table that's the natural
thing to do.
Co-developed-by: Claude Opus 4.6 <noreply@anthropic.com>
The fix in 8f1751a111 made me wonder if we could automatically detect
when pointers are accessed but when this might not be safe. Systemd
is already using a lot of `assert(dst)` and this change now forces
us to use them.
So this commit (ab)uses coccinelle to flag any pointer parameter
dereference not preceded by assert(param), ASSERT_PTR(param), or an
explicit NULL check. It adds integration into meson as a new "coccinelle"
test suite (just like clang-tidy) and is run in CI. The check is not
perfect but seems a reasonable heuristic.
For this RFC commit it is scoped to a subset, it excludes 25 dirs right
now and includes around 100. About 300 warnings left. Busywork that I am
happy to do if there is agreement that it is worth it.
With this in place we would have caught the bug from 8f1751a111 in CI:
```
FAIL: check-pointer-deref.cocci found issues in systemd/src/boot:
diff -u -p systemd/src/boot/measure.c /tmp/nothing/measure.c
--- systemd/src/boot/measure.c
+++ /tmp/nothing/measure.c
@@ -312,7 +312,6 @@ EFI_STATUS tpm_log_tagged_event(
if (err != EFI_SUCCESS)
return err;
- *ret_measured = true;
return EFI_SUCCESS;
}
```
This also adds a new POINTER_MAY_BE_NULL() for the cases when the
called function will do the NULL check (like `iovec_is_set()`).
So far we always conditioned our TPM magic on the UKI having detected
TPM support in the firmware. This is a bit limiting when we want to
support a software TPM that is not visible to the firmware. Hence let's
split this up, and add a separate control that can be set via the kernel
command line. However, as before, let's by default inherit the firmare
TPM discovery state into it, to retain the current behaviour unless
overriden.
With this in place, boot with "systemd.tpm2_measured_os=1
systemd.tpm2_software_fallback=1" on the kernel cmdline to get the swtpm
fallback and then a measured OS based on it.
Typically, the top-level JSON object has to be an object, in any json
document we parse, hence let's add a simple way to enforce that.
Make use of this in various places.
(Note, various other JSON parsers insist on this logic right from the
beginning, but I actually thinking making this insisting optional like
this patch does it is the cleaner approach)
We often have a pattern where the same verb function is used for
multiple actions. This leads to an antipattern where we figure out what
action needs to be taken from argv[0] multiple times: often once in
parse_argv() to figure out what options are allowed, then once again
implicitly in dispatch_verb(), and then again in the action verb itself.
Let's allow passing a parameter into the verb to simplify this.
This matches a pattern we have in conf-parser.h, where we have both
void *userdata (more global) and void *data (per-config item). Here,
I opted for uintptr_t userdata. It seems that most of the time we'll
want to just pass an enum value. This works OK with no casts. I also
tried a void* and union. In both cases, much more boilerplate is needed:
either a cast or a macro to help avoid compiler warnings. uintptr_t
seems generic enough to cover foreseeable usecases with no fuss.
This is a noop refactoring. See next commit for an example.
Add the libfido2 dependency to cryptenroll and cryptsetup's
meson files. If libfido2's not installed in the default path
the build wasn't finding its headers correctly.
When 'tpm2-primary-alg' is missing in LUKS JSON token, the output of
'cryptsetup luksDump' is always:
tpm2-primary-alg: ecc
because tpm2_parse_luks2_json() returns the default (TPM2_ALG_ECC). This can be
misleading and wrong. Make tpm2_parse_luks2_json() return the reality and move
the default to tpm2_unseal().
Let's pick the default NvPCR name to use inside of cryptsetup itself, instead
of in the generator. I think this is the better choice, since it means
the default can also be used if the regular verittab generator is used
instead of the gpt-auto generator.
The expected hash (SHA265 HMAC signature) uses the exact same algorithm which
is used to calculate sha256 PCR bank digest when 'tpm2-measure-pcr=' is used.
Alberto Planas
Fabian Vogt
Zbigniew Jędrzejewski-Szmek
felix h
Paul Meyer
Chris Coulson
dongshengyuan
Yu Watanabe
fuldeka
Kai Lüke
Will Fancher
Daan De Meyer
Luca Boccassi
Vitaly Kuznetsov
Lennart Poettering
Michael Vogt
Dan McGregor