crypto,fs: Separate out hkdf_extract() and hkdf_expand()

Separate out the HKDF functions into a separate module to
to make them available to other callers.
And add a testsuite to the module with tes

crypto,fs: Separate out hkdf_extract() and hkdf_expand()

Separate out the HKDF functions into a separate module to
to make them available to other callers.
And add a testsuite to the module with test vectors
from RFC 5869 (and additional vectors for SHA384 and SHA512)
to ensure the integrity of the algorithm.

Signed-off-by: Hannes Reinecke <[email protected]>
Acked-by: Eric Biggers <[email protected]>
Acked-by: Herbert Xu <[email protected]>
Signed-off-by: Keith Busch <[email protected]>

show more ...

crypto: Kconfig - Select LIB generic option

Select the generic LIB options if the Crypto API algorithm is
enabled. Otherwise this may lead to a build failure as the Crypto
API algorithm always uses

crypto: Kconfig - Select LIB generic option

Select the generic LIB options if the Crypto API algorithm is
enabled. Otherwise this may lead to a build failure as the Crypto
API algorithm always uses the generic implementation.

Fixes: 17ec3e71ba79 ("crypto: lib/Kconfig - Hide arch options from user")
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto/krb5: Implement Kerberos crypto core

Provide core structures, an encoding-type registry and basic module and
config bits for a generic Kerberos crypto library.

Signed-off-by: David Howells <

crypto/krb5: Implement Kerberos crypto core

Provide core structures, an encoding-type registry and basic module and
config bits for a generic Kerberos crypto library.

Signed-off-by: David Howells <[email protected]>
cc: Herbert Xu <[email protected]>
cc: "David S. Miller" <[email protected]>
cc: Chuck Lever <[email protected]>
cc: Marc Dionne <[email protected]>
cc: Eric Dumazet <[email protected]>
cc: Jakub Kicinski <[email protected]>
cc: Paolo Abeni <[email protected]>
cc: Simon Horman <[email protected]>
cc: [email protected]
cc: [email protected]
cc: [email protected]
cc: [email protected]

show more ...

crypto: Add 'krb5enc' hash and cipher AEAD algorithm

Add an AEAD template that does hash-then-cipher (unlike authenc that does
cipher-then-hash). This is required for a number of Kerberos 5 encodin

crypto: Add 'krb5enc' hash and cipher AEAD algorithm

Add an AEAD template that does hash-then-cipher (unlike authenc that does
cipher-then-hash). This is required for a number of Kerberos 5 encoding
types.

[!] Note that the net/sunrpc/auth_gss/ implementation gets a pair of
ciphers, one non-CTS and one CTS, using the former to do all the aligned
blocks and the latter to do the last two blocks if they aren't also
aligned. It may be necessary to do this here too for performance reasons -
but there are considerations both ways:

(1) firstly, there is an optimised assembly version of cts(cbc(aes)) on
x86_64 that should be used instead of having two ciphers;

(2) secondly, none of the hardware offload drivers seem to offer CTS
support (Intel QAT does not, for instance).

However, I don't know if it's possible to query the crypto API to find out
whether there's an optimised CTS algorithm available.

Signed-off-by: David Howells <[email protected]>
cc: Herbert Xu <[email protected]>
cc: "David S. Miller" <[email protected]>
cc: Chuck Lever <[email protected]>
cc: Marc Dionne <[email protected]>
cc: Eric Dumazet <[email protected]>
cc: Jakub Kicinski <[email protected]>
cc: Paolo Abeni <[email protected]>
cc: Simon Horman <[email protected]>
cc: [email protected]
cc: [email protected]
cc: [email protected]
cc: [email protected]

show more ...

crypto: lib/Kconfig - Hide arch options from user

The ARCH_MAY_HAVE patch missed arm64, mips and s390. But it may
also lead to arch options being enabled but ineffective because
of modular/built-in

crypto: lib/Kconfig - Hide arch options from user

The ARCH_MAY_HAVE patch missed arm64, mips and s390. But it may
also lead to arch options being enabled but ineffective because
of modular/built-in conflicts.

As the primary user of all these options wireguard is selecting
the arch options anyway, make the same selections at the lib/crypto
option level and hide the arch options from the user.

Instead of selecting them centrally from lib/crypto, simply set
the default of each arch option as suggested by Eric Biggers.

Change the Crypto API generic algorithms to select the top-level
lib/crypto options instead of the generic one as otherwise there
is no way to enable the arch options (Eric Biggers). Introduce a
set of INTERNAL options to work around dependency cycles on the
CONFIG_CRYPTO symbol.

Fixes: 1047e21aecdf ("crypto: lib/Kconfig - Fix lib built-in failure when arch is modular")
Reported-by: kernel test robot <[email protected]>
Reported-by: Arnd Bergmann <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: crct10dif - remove from crypto API

Remove the "crct10dif" shash algorithm from the crypto API. It has no
known user now that the lib is no longer built on top of it. It has no
remaining re

crypto: crct10dif - remove from crypto API

Remove the "crct10dif" shash algorithm from the crypto API. It has no
known user now that the lib is no longer built on top of it. It has no
remaining references in kernel code. The only other potential users
would be the usual components that allow specifying arbitrary hash
algorithms by name, namely AF_ALG and dm-integrity. However there are
no indications that "crct10dif" is being used with these components.
Debian Code Search and web searches don't find anything relevant, and
explicitly grepping the source code of the usual suspects (cryptsetup,
libell, iwd) finds no matches either. "crc32" and "crc32c" are used in
a few more places, but that doesn't seem to be the case for "crct10dif".

crc_t10dif_update() is also tested by crc_kunit now, so the test
coverage provided via the crypto self-tests is no longer needed.

Also note that the "crct10dif" shash algorithm was inconsistent with the
rest of the shash API in that it wrote the digest in CPU endianness,
making the resulting byte array differ on little endian vs. big endian
platforms. This means it was effectively just built for use by the lib
functions, and it was not actually correct to treat it as "just another
hash function" that could be dropped in via the shash API.

Reviewed-by: Ard Biesheuvel <[email protected]>
Reviewed-by: "Martin K. Petersen" <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Eric Biggers <[email protected]>

show more ...

crypto: crc64-rocksoft - remove from crypto API

Remove crc64-rocksoft from the crypto API. It has no known user now
that the lib is no longer built on top of it. It was also added much
more recent

crypto: crc64-rocksoft - remove from crypto API

Remove crc64-rocksoft from the crypto API. It has no known user now
that the lib is no longer built on top of it. It was also added much
more recently than the longstanding crc32 and crc32c. Unlike crc32 and
crc32c, crc64-rocksoft is also not mentioned in the dm-integrity
documentation and there are no references to it in anywhere in the
cryptsetup git repo, so it is unlikely to have any user there either.

Also, this CRC variant is named incorrectly; it has nothing to do with
Rocksoft and should be called crc64-nvme. That is yet another reason to
remove it from the crypto API; we would not want anyone to start
depending on the current incorrect algorithm name of crc64-rocksoft.

Note that this change temporarily makes this CRC variant not be covered
by any tests, as previously it was relying on the crypto self-tests.
This will be fixed by adding this CRC variant to crc_kunit.

Reviewed-by: Ard Biesheuvel <[email protected]>
Reviewed-by: "Martin K. Petersen" <[email protected]>
Acked-by: Keith Busch <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Eric Biggers <[email protected]>

show more ...

crypto: keywrap - remove unused keywrap algorithm

The keywrap (kw) algorithm has no in-tree user. It has never had an
in-tree user, and the patch that added it provided no justification for
its inc

crypto: keywrap - remove unused keywrap algorithm

The keywrap (kw) algorithm has no in-tree user. It has never had an
in-tree user, and the patch that added it provided no justification for
its inclusion. Even use of it via AF_ALG is impossible, as it uses a
weird calling convention where part of the ciphertext is returned via
the IV buffer, which is not returned to userspace in AF_ALG.

It's also unclear whether any new code in the kernel that does key
wrapping would actually use this algorithm. It is controversial in the
cryptographic community due to having no clearly stated security goal,
no security proof, poor performance, and only a 64-bit auth tag. Later
work (https://eprint.iacr.org/2006/221) suggested that the goal is
deterministic authenticated encryption. But there are now more modern
algorithms for this, and this is not the same as key wrapping, for which
a regular AEAD such as AES-GCM usually can be (and is) used instead.

Therefore, remove this unused code.

There were several special cases for this algorithm in the self-tests,
due to its weird calling convention. Remove those too.

Cc: Stephan Mueller <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> # m68k
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: vmac - remove unused VMAC algorithm

Remove the vmac64 template, as it has no known users. It also continues
to have longstanding bugs such as alignment violations (see
https://lore.kernel.o

crypto: vmac - remove unused VMAC algorithm

Remove the vmac64 template, as it has no known users. It also continues
to have longstanding bugs such as alignment violations (see
https://lore.kernel.org/r/[email protected]/).

This code was added in 2009 by commit f1939f7c5645 ("crypto: vmac - New
hash algorithm for intel_txt support"). Based on the mention of
intel_txt support in the commit title, it seems it was added as a
prerequisite for the contemporaneous patch
"intel_txt: add s3 userspace memory integrity verification"
(https://lore.kernel.org/r/[email protected]/). In the design
proposed by that patch, when an Intel Trusted Execution Technology (TXT)
enabled system resumed from suspend, the "tboot" trusted executable
launched the Linux kernel without verifying userspace memory, and then
the Linux kernel used VMAC to verify userspace memory.

However, that patch was never merged, as reviewers had objected to the
design. It was later reworked into commit 4bd96a7a8185 ("x86, tboot:
Add support for S3 memory integrity protection") which made tboot verify
the memory instead. Thus the VMAC support in Linux was never used.

No in-tree user has appeared since then, other than potentially the
usual components that allow specifying arbitrary hash algorithms by
name, namely AF_ALG and dm-integrity. However there are no indications
that VMAC is being used with these components. Debian Code Search and
web searches for "vmac64" (the actual algorithm name) do not return any
results other than the kernel itself, suggesting that it does not appear
in any other code or documentation. Explicitly grepping the source code
of the usual suspects (libell, iwd, cryptsetup) finds no matches either.

Before 2018, the vmac code was also completely broken due to using a
hardcoded nonce and the wrong endianness for the MAC. It was then fixed
by commit ed331adab35b ("crypto: vmac - add nonced version with big
endian digest") and commit 0917b873127c ("crypto: vmac - remove insecure
version with hardcoded nonce"). These were intentionally breaking
changes that changed all the computed MAC values as well as the
algorithm name ("vmac" to "vmac64"). No complaints were ever received
about these breaking changes, strongly suggesting the absence of users.

The reason I had put some effort into fixing this code in 2018 is
because it was used by an out-of-tree driver. But if it is still needed
in that particular out-of-tree driver, the code can be carried in that
driver instead. There is no need to carry it upstream.

Cc: Atharva Tiwari <[email protected]>
Cc: Shane Wang <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Acked-by: Geert Uytterhoeven <[email protected]> # m68k
Signed-off-by: Herbert Xu <[email protected]>

show more ...

lib/crc-t10dif: stop wrapping the crypto API

In preparation for making the CRC-T10DIF library directly optimized for
each architecture, like what has been done for CRC32, get rid of the
weird layeri

lib/crc-t10dif: stop wrapping the crypto API

In preparation for making the CRC-T10DIF library directly optimized for
each architecture, like what has been done for CRC32, get rid of the
weird layering where crc_t10dif_update() calls into the crypto API.
Instead, move crc_t10dif_generic() into the crc-t10dif library module,
and make crc_t10dif_update() just call crc_t10dif_generic().
Acceleration will be reintroduced via crc_t10dif_arch() in the following
patches.

Reviewed-by: Ard Biesheuvel <[email protected]>
Reviewed-by: Martin K. Petersen <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Eric Biggers <[email protected]>

show more ...

crypto: ecdsa - Update Kconfig help text for NIST P521

Commit a7d45ba77d3d ("crypto: ecdsa - Register NIST P521 and extend test
suite") added support for ECDSA signature verification using NIST P521

crypto: ecdsa - Update Kconfig help text for NIST P521

Commit a7d45ba77d3d ("crypto: ecdsa - Register NIST P521 and extend test
suite") added support for ECDSA signature verification using NIST P521,
but forgot to amend the Kconfig help text. Fix it.

Fixes: a7d45ba77d3d ("crypto: ecdsa - Register NIST P521 and extend test suite")
Signed-off-by: Lukas Wunner <[email protected]>
Reviewed-by: Stefan Berger <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: rsassa-pkcs1 - Migrate to sig_alg backend

A sig_alg backend has just been introduced with the intent of moving all
asymmetric sign/verify algorithms to it one by one.

Migrate the sign/verif

crypto: rsassa-pkcs1 - Migrate to sig_alg backend

A sig_alg backend has just been introduced with the intent of moving all
asymmetric sign/verify algorithms to it one by one.

Migrate the sign/verify operations from rsa-pkcs1pad.c to a separate
rsassa-pkcs1.c which uses the new backend.

Consequently there are now two templates which build on the "rsa"
akcipher_alg:

* The existing "pkcs1pad" template, which is instantiated as an
akcipher_instance and retains the encrypt/decrypt operations of
RSAES-PKCS1-v1_5 (RFC 8017 sec 7.2).

* The new "pkcs1" template, which is instantiated as a sig_instance
and contains the sign/verify operations of RSASSA-PKCS1-v1_5
(RFC 8017 sec 8.2).

In a separate step, rsa-pkcs1pad.c could optionally be renamed to
rsaes-pkcs1.c for clarity. Additional "oaep" and "pss" templates
could be added for RSAES-OAEP and RSASSA-PSS.

Note that it's currently allowed to allocate a "pkcs1pad(rsa)" transform
without specifying a hash algorithm. That makes sense if the transform
is only used for encrypt/decrypt and continues to be supported. But for
sign/verify, such transforms previously did not insert the Full Hash
Prefix into the padding. The resulting message encoding was incompliant
with EMSA-PKCS1-v1_5 (RFC 8017 sec 9.2) and therefore nonsensical.

From here on in, it is no longer allowed to allocate a transform without
specifying a hash algorithm if the transform is used for sign/verify
operations. This simplifies the code because the insertion of the Full
Hash Prefix is no longer optional, so various "if (digest_info)" clauses
can be removed.

There has been a previous attempt to forbid transform allocation without
specifying a hash algorithm, namely by commit c0d20d22e0ad ("crypto:
rsa-pkcs1pad - Require hash to be present"). It had to be rolled back
with commit b3a8c8a5ebb5 ("crypto: rsa-pkcs1pad: Allow hash to be
optional [ver #2]"), presumably because it broke allocation of a
transform which was solely used for encrypt/decrypt, not sign/verify.
Avoid such breakage by allowing transform allocation for encrypt/decrypt
with and without specifying a hash algorithm (and simply ignoring the
hash algorithm in the former case).

So again, specifying a hash algorithm is now mandatory for sign/verify,
but optional and ignored for encrypt/decrypt.

The new sig_alg API uses kernel buffers instead of sglists, which
avoids the overhead of copying signature and digest from sglists back
into kernel buffers. rsassa-pkcs1.c is thus simplified quite a bit.

sig_alg is always synchronous, whereas the underlying "rsa" akcipher_alg
may be asynchronous. So await the result of the akcipher_alg, similar
to crypto_akcipher_sync_{en,de}crypt().

As part of the migration, rename "rsa_digest_info" to "hash_prefix" to
adhere to the spec language in RFC 9580. Otherwise keep the code
unmodified wherever possible to ease reviewing and bisecting. Leave
several simplification and hardening opportunities to separate commits.

rsassa-pkcs1.c uses modern __free() syntax for allocation of buffers
which need to be freed by kfree_sensitive(), hence a DEFINE_FREE()
clause for kfree_sensitive() is introduced herein as a byproduct.

Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: ecrdsa - Migrate to sig_alg backend

A sig_alg backend has just been introduced with the intent of moving all
asymmetric sign/verify algorithms to it one by one.

Migrate ecrdsa.c to the new

crypto: ecrdsa - Migrate to sig_alg backend

A sig_alg backend has just been introduced with the intent of moving all
asymmetric sign/verify algorithms to it one by one.

Migrate ecrdsa.c to the new backend.

One benefit of the new API is the use of kernel buffers instead of
sglists, which avoids the overhead of copying signature and digest
sglists back into kernel buffers. ecrdsa.c is thus simplified quite
a bit.

Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: ecdsa - Migrate to sig_alg backend

A sig_alg backend has just been introduced with the intent of moving all
asymmetric sign/verify algorithms to it one by one.

Migrate ecdsa.c to the new ba

crypto: ecdsa - Migrate to sig_alg backend

A sig_alg backend has just been introduced with the intent of moving all
asymmetric sign/verify algorithms to it one by one.

Migrate ecdsa.c to the new backend.

One benefit of the new API is the use of kernel buffers instead of
sglists, which avoids the overhead of copying signature and digest
sglists back into kernel buffers. ecdsa.c is thus simplified quite
a bit.

Signed-off-by: Lukas Wunner <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: jitter - set default OSR to 3

The user space Jitter RNG library uses the oversampling rate of 3 which
implies that each time stamp is credited with 1/3 bit of entropy. To
obtain 256 bits of

crypto: jitter - set default OSR to 3

The user space Jitter RNG library uses the oversampling rate of 3 which
implies that each time stamp is credited with 1/3 bit of entropy. To
obtain 256 bits of entropy, 768 time stamps need to be sampled. The
increase in OSR is applied based on a report where the Jitter RNG is
used on a system exhibiting a challenging environment to collect
entropy.

This OSR default value is now applied to the Linux kernel version of
the Jitter RNG as well.

The increase in the OSR from 1 to 3 also implies that the Jitter RNG is
now slower by default.

Reported-by: Jeff Barnes <[email protected]>
Signed-off-by: Stephan Mueller <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: sm2 - Remove sm2 algorithm

The SM2 algorithm has a single user in the kernel. However, it's
never been integrated properly with that user: asymmetric_keys.

The crux of the issue is that th

crypto: sm2 - Remove sm2 algorithm

The SM2 algorithm has a single user in the kernel. However, it's
never been integrated properly with that user: asymmetric_keys.

The crux of the issue is that the way it computes its digest with
sm3 does not fit into the architecture of asymmetric_keys. As no
solution has been proposed, remove this algorithm.

It can be resubmitted when it is integrated properly into the
asymmetric_keys subsystem.

Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: remove CONFIG_CRYPTO_STATS

Remove support for the "Crypto usage statistics" feature
(CONFIG_CRYPTO_STATS). This feature does not appear to have ever been
used, and it is harmful because it

crypto: remove CONFIG_CRYPTO_STATS

Remove support for the "Crypto usage statistics" feature
(CONFIG_CRYPTO_STATS). This feature does not appear to have ever been
used, and it is harmful because it significantly reduces performance and
is a large maintenance burden.

Covering each of these points in detail:

1. Feature is not being used

Since these generic crypto statistics are only readable using netlink,
it's fairly straightforward to look for programs that use them. I'm
unable to find any evidence that any such programs exist. For example,
Debian Code Search returns no hits except the kernel header and kernel
code itself and translations of the kernel header:
https://codesearch.debian.net/search?q=CRYPTOCFGA_STAT&literal=1&perpkg=1

The patch series that added this feature in 2018
(https://lore.kernel.org/linux-crypto/[email protected]/)
said "The goal is to have an ifconfig for crypto device." This doesn't
appear to have happened.

It's not clear that there is real demand for crypto statistics. Just
because the kernel provides other types of statistics such as I/O and
networking statistics and some people find those useful does not mean
that crypto statistics are useful too.

Further evidence that programs are not using CONFIG_CRYPTO_STATS is that
it was able to be disabled in RHEL and Fedora as a bug fix
(https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/2947).

Even further evidence comes from the fact that there are and have been
bugs in how the stats work, but they were never reported. For example,
before Linux v6.7 hash stats were double-counted in most cases.

There has also never been any documentation for this feature, so it
might be hard to use even if someone wanted to.

2. CONFIG_CRYPTO_STATS significantly reduces performance

Enabling CONFIG_CRYPTO_STATS significantly reduces the performance of
the crypto API, even if no program ever retrieves the statistics. This
primarily affects systems with a large number of CPUs. For example,
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039576 reported
that Lustre client encryption performance improved from 21.7GB/s to
48.2GB/s by disabling CONFIG_CRYPTO_STATS.

It can be argued that this means that CONFIG_CRYPTO_STATS should be
optimized with per-cpu counters similar to many of the networking
counters. But no one has done this in 5+ years. This is consistent
with the fact that the feature appears to be unused, so there seems to
be little interest in improving it as opposed to just disabling it.

It can be argued that because CONFIG_CRYPTO_STATS is off by default,
performance doesn't matter. But Linux distros tend to error on the side
of enabling options. The option is enabled in Ubuntu and Arch Linux,
and until recently was enabled in RHEL and Fedora (see above). So, even
just having the option available is harmful to users.

3. CONFIG_CRYPTO_STATS is a large maintenance burden

There are over 1000 lines of code associated with CONFIG_CRYPTO_STATS,
spread among 32 files. It significantly complicates much of the
implementation of the crypto API. After the initial submission, many
fixes and refactorings have consumed effort of multiple people to keep
this feature "working". We should be spending this effort elsewhere.

Acked-by: Ard Biesheuvel <[email protected]>
Acked-by: Corentin Labbe <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

show more ...

Revert "crypto: remove CONFIG_CRYPTO_STATS"

This reverts commit 2beb81fbf0c01a62515a1bcef326168494ee2bd0.

While removing CONFIG_CRYPTO_STATS is a worthy goal, this also
removed unrelated infrastruc

Revert "crypto: remove CONFIG_CRYPTO_STATS"

This reverts commit 2beb81fbf0c01a62515a1bcef326168494ee2bd0.

While removing CONFIG_CRYPTO_STATS is a worthy goal, this also
removed unrelated infrastructure such as crypto_comp_alg_common.

Signed-off-by: Herbert Xu <[email protected]>

show more ...

crypto: remove CONFIG_CRYPTO_STATS

Remove support for the "Crypto usage statistics" feature
(CONFIG_CRYPTO_STATS). This feature does not appear to have ever been
used, and it is harmful because it

crypto: remove CONFIG_CRYPTO_STATS

Remove support for the "Crypto usage statistics" feature
(CONFIG_CRYPTO_STATS). This feature does not appear to have ever been
used, and it is harmful because it significantly reduces performance and
is a large maintenance burden.

Covering each of these points in detail:

1. Feature is not being used

Since these generic crypto statistics are only readable using netlink,
it's fairly straightforward to look for programs that use them. I'm
unable to find any evidence that any such programs exist. For example,
Debian Code Search returns no hits except the kernel header and kernel
code itself and translations of the kernel header:
https://codesearch.debian.net/search?q=CRYPTOCFGA_STAT&literal=1&perpkg=1

The patch series that added this feature in 2018
(https://lore.kernel.org/linux-crypto/[email protected]/)
said "The goal is to have an ifconfig for crypto device." This doesn't
appear to have happened.

It's not clear that there is real demand for crypto statistics. Just
because the kernel provides other types of statistics such as I/O and
networking statistics and some people find those useful does not mean
that crypto statistics are useful too.

Further evidence that programs are not using CONFIG_CRYPTO_STATS is that
it was able to be disabled in RHEL and Fedora as a bug fix
(https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/2947).

Even further evidence comes from the fact that there are and have been
bugs in how the stats work, but they were never reported. For example,
before Linux v6.7 hash stats were double-counted in most cases.

There has also never been any documentation for this feature, so it
might be hard to use even if someone wanted to.

2. CONFIG_CRYPTO_STATS significantly reduces performance

Enabling CONFIG_CRYPTO_STATS significantly reduces the performance of
the crypto API, even if no program ever retrieves the statistics. This
primarily affects systems with large number of CPUs. For example,
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2039576 reported
that Lustre client encryption performance improved from 21.7GB/s to
48.2GB/s by disabling CONFIG_CRYPTO_STATS.

It can be argued that this means that CONFIG_CRYPTO_STATS should be
optimized with per-cpu counters similar to many of the networking
counters. But no one has done this in 5+ years. This is consistent
with the fact that the feature appears to be unused, so there seems to
be little interest in improving it as opposed to just disabling it.

It can be argued that because CONFIG_CRYPTO_STATS is off by default,
performance doesn't matter. But Linux distros tend to error on the side
of enabling options. The option is enabled in Ubuntu and Arch Linux,
and until recently was enabled in RHEL and Fedora (see above). So, even
just having the option available is harmful to users.

3. CONFIG_CRYPTO_STATS is a large maintenance burden

There are over 1000 lines of code associated with CONFIG_CRYPTO_STATS,
spread among 32 files. It significantly complicates much of the
implementation of the crypto API. After the initial submission, many
fixes and refactorings have consumed effort of multiple people to keep
this feature "working". We should be spending this effort elsewhere.

Cc: Corentin Labbe <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Acked-by: Corentin Labbe <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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crypto: jitter - fix CRYPTO_JITTERENTROPY help text

Correct various small problems in the help text:
a. change 2 spaces to ", "
b. finish an incomplete sentence
c. change non-working URL to working

crypto: jitter - fix CRYPTO_JITTERENTROPY help text

Correct various small problems in the help text:
a. change 2 spaces to ", "
b. finish an incomplete sentence
c. change non-working URL to working URL

Fixes: a9a98d49da52 ("crypto: Kconfig - simplify compression/RNG entries")
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218458
Signed-off-by: Randy Dunlap <[email protected]>
Cc: Bagas Sanjaya <[email protected]>
Cc: Robert Elliott <[email protected]>
Cc: Christoph Biedl <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: [email protected]
Acked-by: Bagas Sanjaya <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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RISC-V: hook new crypto subdir into build-system

Create a crypto subdirectory for added accelerated cryptography routines
and hook it into the riscv Kbuild and the main crypto Kconfig.

Signed-off-b

RISC-V: hook new crypto subdir into build-system

Create a crypto subdirectory for added accelerated cryptography routines
and hook it into the riscv Kbuild and the main crypto Kconfig.

Signed-off-by: Heiko Stuebner <[email protected]>
Reviewed-by: Eric Biggers <[email protected]>
Signed-off-by: Jerry Shih <[email protected]>
Signed-off-by: Eric Biggers <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Palmer Dabbelt <[email protected]>

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crypto: cfb,ofb - Remove cfb and ofb

Remove the unused algorithms CFB/OFB.

Signed-off-by: Herbert Xu <[email protected]>

crypto: jitterentropy - Hide esoteric Kconfig options under FIPS and EXPERT

As JITTERENTROPY is selected by default if you enable the CRYPTO
API, any Kconfig options added there will show up for eve

crypto: jitterentropy - Hide esoteric Kconfig options under FIPS and EXPERT

As JITTERENTROPY is selected by default if you enable the CRYPTO
API, any Kconfig options added there will show up for every single
user. Hide the esoteric options under EXPERT as well as FIPS so
that only distro makers will see them.

Reported-by: Linus Torvalds <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
Reviewed-by: Stephan Mueller <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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crypto: skcipher - Add dependency on ecb

As lskcipher requires the ecb wrapper for the transition add an
explicit dependency on it so that it is always present. This can
be removed once all simple

crypto: skcipher - Add dependency on ecb

As lskcipher requires the ecb wrapper for the transition add an
explicit dependency on it so that it is always present. This can
be removed once all simple ciphers have been converted to lskcipher.

Reported-by: Nathan Chancellor <[email protected]>
Fixes: 705b52fef3c7 ("crypto: cbc - Convert from skcipher to lskcipher")
Signed-off-by: Herbert Xu <[email protected]>
Tested-by: Nathan Chancellor <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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crypto: jitter - Allow configuration of oversampling rate

The oversampling rate used by the Jitter RNG allows the configuration of
the heuristically implied entropy in one timing measurement. This
e

crypto: jitter - Allow configuration of oversampling rate

The oversampling rate used by the Jitter RNG allows the configuration of
the heuristically implied entropy in one timing measurement. This
entropy rate is (1 / OSR) bits of entropy per time stamp.

Considering that the Jitter RNG now support APT/RCT health tests for
different OSRs, allow this value to be configured at compile time to
support systems with limited amount of entropy in their timer.

The allowed range of OSR values complies with the APT/RCT cutoff health
test values which range from 1 through 15.

The default value of the OSR selection support is left at 1 which is the
current default. Thus, the addition of the configuration support does
not alter the default Jitter RNG behavior.

Signed-off-by: Stephan Mueller <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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