crypto: aead - use str_yes_no() helper in crypto_aead_show()

Remove hard-coded strings by using the str_yes_no() helper function.

Signed-off-by: Thorsten Blum <[email protected]>
Signed-off-b

crypto: aead - use str_yes_no() helper in crypto_aead_show()

Remove hard-coded strings by using the str_yes_no() helper function.

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

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crypto: aead,cipher - zeroize key buffer after use

I.G 9.7.B for FIPS 140-3 specifies that variables temporarily holding
cryptographic information should be zeroized once they are no longer
needed.

crypto: aead,cipher - zeroize key buffer after use

I.G 9.7.B for FIPS 140-3 specifies that variables temporarily holding
cryptographic information should be zeroized once they are no longer
needed. Accomplish this by using kfree_sensitive for buffers that
previously held the private key.

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

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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]>

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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]>

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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: aead - Add crypto_has_aead

Add the helper crypto_has_aead. This is meant to replace the
existing use of crypto_has_alg to locate AEAD algorithms.

Signed-off-by: Herbert Xu <herbert@gondor.

crypto: aead - Add crypto_has_aead

Add the helper crypto_has_aead. This is meant to replace the
existing use of crypto_has_alg to locate AEAD algorithms.

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

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crypto: api - Fix CRYPTO_USER checks for report function

Checking the config via ifdef incorrectly compiles out the report
functions when CRYPTO_USER is set to =m. Fix it by using IS_ENABLED()
inste

crypto: api - Fix CRYPTO_USER checks for report function

Checking the config via ifdef incorrectly compiles out the report
functions when CRYPTO_USER is set to =m. Fix it by using IS_ENABLED()
instead.

Fixes: c0f9e01dd266 ("crypto: api - Check CRYPTO_USER instead of NET for report")
Signed-off-by: Ondrej Mosnacek <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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crypto: api - Check CRYPTO_USER instead of NET for report

The report function is currently conditionalised on CONFIG_NET.
As it's only used by CONFIG_CRYPTO_USER, conditionalising on that
instead of

crypto: api - Check CRYPTO_USER instead of NET for report

The report function is currently conditionalised on CONFIG_NET.
As it's only used by CONFIG_CRYPTO_USER, conditionalising on that
instead of CONFIG_NET makes more sense.

This gets rid of a rarely used code-path.

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

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crypto: aead - Count error stats differently

Move all stat code specific to aead into the aead code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case

crypto: aead - Count error stats differently

Move all stat code specific to aead into the aead code.

While we're at it, change the stats so that bytes and counts
are always incremented even in case of error. This allows the
reference counting to be removed as we can now increment the
counters prior to the operation.

After the operation we simply increase the error count if necessary.
This is safe as errors can only occur synchronously (or rather,
the existing code already ignored asynchronous errors which are
only visible to the callback function).

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

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crypto: algapi - enforce that all instances have a ->free() method

All instances need to have a ->free() method, but people could forget to
set it and then not notice if the instance is never unregi

crypto: algapi - enforce that all instances have a ->free() method

All instances need to have a ->free() method, but people could forget to
set it and then not notice if the instance is never unregistered. To
help detect this bug earlier, don't allow an instance without a ->free()
method to be registered, and complain loudly if someone tries to do it.

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

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crypto: algapi - remove crypto_template::{alloc,free}()

Now that all templates provide a ->create() method which creates an
instance, installs a strongly-typed ->free() method directly to it, and
re

crypto: algapi - remove crypto_template::{alloc,free}()

Now that all templates provide a ->create() method which creates an
instance, installs a strongly-typed ->free() method directly to it, and
registers it, the older ->alloc() and ->free() methods in
'struct crypto_template' are no longer used. Remove them.

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

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crypto: algapi - pass instance to crypto_grab_spawn()

Currently, crypto_spawn::inst is first used temporarily to pass the
instance to crypto_grab_spawn(). Then crypto_init_spawn() overwrites it
wit

crypto: algapi - pass instance to crypto_grab_spawn()

Currently, crypto_spawn::inst is first used temporarily to pass the
instance to crypto_grab_spawn(). Then crypto_init_spawn() overwrites it
with crypto_spawn::next, which shares the same union. Finally,
crypto_spawn::inst is set again when the instance is registered.

Make this less convoluted by just passing the instance as an argument to
crypto_grab_spawn() instead.

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

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crypto: aead - pass instance to crypto_grab_aead()

Initializing a crypto_aead_spawn currently requires:

1. Set spawn->base.inst to point to the instance.
2. Call crypto_grab_aead().

But there's no

crypto: aead - pass instance to crypto_grab_aead()

Initializing a crypto_aead_spawn currently requires:

1. Set spawn->base.inst to point to the instance.
2. Call crypto_grab_aead().

But there's no reason for these steps to be separate, and in fact this
unneeded complication has caused at least one bug, the one fixed by
commit 6db43410179b ("crypto: adiantum - initialize crypto_spawn::inst")

So just make crypto_grab_aead() take the instance as an argument.

To keep the function calls from getting too unwieldy due to this extra
argument, also introduce a 'mask' variable into the affected places
which weren't already using one.

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

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crypto: aead - Split out geniv into its own module

If aead is built as a module along with cryptomgr, it creates a
dependency loop due to the dependency chain aead => crypto_null =>
cryptomgr => aea

crypto: aead - Split out geniv into its own module

If aead is built as a module along with cryptomgr, it creates a
dependency loop due to the dependency chain aead => crypto_null =>
cryptomgr => aead.

This is due to the presence of the AEAD geniv code. This code is
not really part of the AEAD API but simply support code for IV
generators such as seqiv. This patch moves the geniv code into
its own module thus breaking the dependency loop.

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

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crypto: aead - Do not allow authsize=0 if auth. alg has digestsize>0

Return -EINVAL on an attempt to set the authsize to 0 with an auth.
algorithm with a non-zero digestsize (i.e. anything but diges

crypto: aead - Do not allow authsize=0 if auth. alg has digestsize>0

Return -EINVAL on an attempt to set the authsize to 0 with an auth.
algorithm with a non-zero digestsize (i.e. anything but digest_null)
as authenticating the data and then throwing away the result does not
make any sense at all.

The digestsize zero exception is for use with digest_null for testing
purposes only.

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

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crypto: aead - un-inline encrypt and decrypt functions

crypto_aead_encrypt() and crypto_aead_decrypt() have grown to be more
than a single indirect function call. They now also check whether a key

crypto: aead - un-inline encrypt and decrypt functions

crypto_aead_encrypt() and crypto_aead_decrypt() have grown to be more
than a single indirect function call. They now also check whether a key
has been set, the decryption side checks whether the input is at least
as long as the authentication tag length, and with CONFIG_CRYPTO_STATS=y
they also update the crypto statistics. That can add up to a lot of
bloat at every call site. Moreover, these always involve a function
call anyway, which greatly limits the benefits of inlining.

So change them to be non-inline.

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

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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crypto: aead - set CRYPTO_TFM_NEED_KEY if ->setkey() fails

Some algorithms have a ->setkey() method that is not atomic, in the
sense that setting a key can fail after changes were already made to th

crypto: aead - set CRYPTO_TFM_NEED_KEY if ->setkey() fails

Some algorithms have a ->setkey() method that is not atomic, in the
sense that setting a key can fail after changes were already made to the
tfm context. In this case, if a key was already set the tfm can end up
in a state that corresponds to neither the old key nor the new key.

For example, in gcm.c, if the kzalloc() fails due to lack of memory,
then the CTR part of GCM will have the new key but GHASH will not.

It's not feasible to make all ->setkey() methods atomic, especially ones
that have to key multiple sub-tfms. Therefore, make the crypto API set
CRYPTO_TFM_NEED_KEY if ->setkey() fails, to prevent the tfm from being
used until a new key is set.

[Cc stable mainly because when introducing the NEED_KEY flag I changed
AF_ALG to rely on it; and unlike in-kernel crypto API users, AF_ALG
previously didn't have this problem. So these "incompletely keyed"
states became theoretically accessible via AF_ALG -- though, the
opportunities for causing real mischief seem pretty limited.]

Fixes: dc26c17f743a ("crypto: aead - prevent using AEADs without setting key")
Cc: <[email protected]> # v4.16+
Signed-off-by: Eric Biggers <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>

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crypto: user - clean up report structure copying

There have been a pretty ridiculous number of issues with initializing
the report structures that are copied to userspace by NETLINK_CRYPTO.
Commit 4

crypto: user - clean up report structure copying

There have been a pretty ridiculous number of issues with initializing
the report structures that are copied to userspace by NETLINK_CRYPTO.
Commit 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME
expansion") replaced some strncpy()s with strlcpy()s, thereby
introducing information leaks. Later two other people tried to replace
other strncpy()s with strlcpy() too, which would have introduced even
more information leaks:

- https://lore.kernel.org/patchwork/patch/954991/
- https://patchwork.kernel.org/patch/10434351/

Commit cac5818c25d0 ("crypto: user - Implement a generic crypto
statistics") also uses the buggy strlcpy() approach and therefore leaks
uninitialized memory to userspace. A fix was proposed, but it was
originally incomplete.

Seeing as how apparently no one can get this right with the current
approach, change all the reporting functions to:

- Start by memsetting the report structure to 0. This guarantees it's
always initialized, regardless of what happens later.
- Initialize all strings using strscpy(). This is safe after the
memset, ensures null termination of long strings, avoids unnecessary
work, and avoids the -Wstringop-truncation warnings from gcc.
- Use sizeof(var) instead of sizeof(type). This is more robust against
copy+paste errors.

For simplicity, also reuse the -EMSGSIZE return value from nla_put().

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

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crypto: aead - prevent using AEADs without setting key

Similar to what was done for the hash API, update the AEAD API to track
whether each transform has been keyed, and reject encryption/decryption

crypto: aead - prevent using AEADs without setting key

Similar to what was done for the hash API, update the AEAD API to track
whether each transform has been keyed, and reject encryption/decryption
if a key is needed but one hasn't been set.

This isn't quite as important as the equivalent fix for the hash API
because AEADs always require a key, so are unlikely to be used without
one. Still, tracking the key will prevent accidental unkeyed use.
algif_aead also had to track the key anyway, so the new flag replaces
that and slightly simplifies the algif_aead implementation.

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

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crypto: null - Get rid of crypto_{get,put}_default_null_skcipher2()

Since commit 499a66e6b689 ("crypto: null - Remove default null
blkcipher"), crypto_get_default_null_skcipher2() and
crypto_put_def

crypto: null - Get rid of crypto_{get,put}_default_null_skcipher2()

Since commit 499a66e6b689 ("crypto: null - Remove default null
blkcipher"), crypto_get_default_null_skcipher2() and
crypto_put_default_null_skcipher2() are the same as their non-2
equivalents. So switch callers of the "2" versions over to the original
versions and remove the "2" versions.

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

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crypto: Replaced gcc specific attributes with macros from compiler.h

Continuing from this commit: 52f5684c8e1e
("kernel: use macros from compiler.h instead of __attribute__((...))")

I submitted 4 t

crypto: Replaced gcc specific attributes with macros from compiler.h

Continuing from this commit: 52f5684c8e1e
("kernel: use macros from compiler.h instead of __attribute__((...))")

I submitted 4 total patches. They are part of task I've taken up to
increase compiler portability in the kernel. I've cleaned up the
subsystems under /kernel /mm /block and /security, this patch targets
/crypto.

There is <linux/compiler.h> which provides macros for various gcc specific
constructs. Eg: __weak for __attribute__((weak)). I've cleaned all
instances of gcc specific attributes with the right macros for the crypto
subsystem.

I had to make one additional change into compiler-gcc.h for the case when
one wants to use this: __attribute__((aligned) and not specify an alignment
factor. From the gcc docs, this will result in the largest alignment for
that data type on the target machine so I've named the macro
__aligned_largest. Please advise if another name is more appropriate.

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

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crypto: aead - Remove blkcipher null for IV generators

The blkcipher null object is no longer used and can now be removed.

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

crypto: aead - Add skcipher null for IV generators

This patch adds an skcipher null object alongside the existing
null blkcipher so that IV generators using it can switch over
to skcipher.

Signed-o

crypto: aead - Add skcipher null for IV generators

This patch adds an skcipher null object alongside the existing
null blkcipher so that IV generators using it can switch over
to skcipher.

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

show more ...

crypto: aead - Add chunk size

This patch adds a chunk size parameter to aead algorithms, just
like the chunk size for skcipher algorithms.

However, unlike skcipher we do not currently export this t

crypto: aead - Add chunk size

This patch adds a chunk size parameter to aead algorithms, just
like the chunk size for skcipher algorithms.

However, unlike skcipher we do not currently export this to AEAD
users. It is only meant to be used by AEAD implementors for now.

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

show more ...