<feed xmlns='http://www.w3.org/2005/Atom'>
<title>pm24.git/crypto/Makefile, branch master</title>
<subtitle>Unnamed repository; edit this file 'description' to name the repository.
</subtitle>
<id>https://git.kobert.dev/pm24.git/atom?h=master</id>
<link rel='self' href='https://git.kobert.dev/pm24.git/atom?h=master'/>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/'/>
<updated>2024-10-28T10:33:10Z</updated>
<entry>
<title>crypto: crc32c - Provide crc32c-arch driver for accelerated library code</title>
<updated>2024-10-28T10:33:10Z</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2024-10-16T18:57:25Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=16739efac6e1ea40df5ec7a263e664481840e73a'/>
<id>urn:sha1:16739efac6e1ea40df5ec7a263e664481840e73a</id>
<content type='text'>
crc32c-generic is currently backed by the architecture's CRC-32c library
code, which may offer a variety of implementations depending on the
capabilities of the platform. These are not covered by the crypto
subsystem's fuzz testing capabilities because crc32c-generic is the
reference driver that the fuzzing logic uses as a source of truth.

Fix this by providing a crc32c-arch implementation which is based on the
arch library code if available, and modify crc32c-generic so it is
always based on the generic C implementation. If the arch has no CRC-32c
library code, this change does nothing.

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: crc32 - Provide crc32-arch driver for accelerated library code</title>
<updated>2024-10-28T10:33:10Z</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2024-10-16T18:57:24Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=a37e55791f204bd65da07d281d95629df15ccf81'/>
<id>urn:sha1:a37e55791f204bd65da07d281d95629df15ccf81</id>
<content type='text'>
crc32-generic is currently backed by the architecture's CRC-32 library
code, which may offer a variety of implementations depending on the
capabilities of the platform. These are not covered by the crypto
subsystem's fuzz testing capabilities because crc32-generic is the
reference driver that the fuzzing logic uses as a source of truth.

Fix this by providing a crc32-arch implementation which is based on the
arch library code if available, and modify crc32-generic so it is
always based on the generic C implementation. If the arch has no CRC-32
library code, this change does nothing.

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: ecdsa - Support P1363 signature decoding</title>
<updated>2024-10-05T05:22:05Z</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2024-09-10T14:30:28Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=b04163863caf599d4348a05af5a71cf5d42f11dc'/>
<id>urn:sha1:b04163863caf599d4348a05af5a71cf5d42f11dc</id>
<content type='text'>
Alternatively to the X9.62 encoding of ecdsa signatures, which uses
ASN.1 and is already supported by the kernel, there's another common
encoding called P1363.  It stores r and s as the concatenation of two
big endian, unsigned integers.  The name originates from IEEE P1363.

Add a P1363 template in support of the forthcoming SPDM library
(Security Protocol and Data Model) for PCI device authentication.

P1363 is prescribed by SPDM 1.2.1 margin no 44:

   "For ECDSA signatures, excluding SM2, in SPDM, the signature shall be
    the concatenation of r and s.  The size of r shall be the size of
    the selected curve.  Likewise, the size of s shall be the size of
    the selected curve.  See BaseAsymAlgo in NEGOTIATE_ALGORITHMS for
    the size of r and s.  The byte order for r and s shall be in big
    endian order.  When placing ECDSA signatures into an SPDM signature
    field, r shall come first followed by s."

Link: https://www.dmtf.org/sites/default/files/standards/documents/DSP0274_1.2.1.pdf
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Reviewed-by: Jonathan Cameron &lt;Jonathan.Cameron@huawei.com&gt;
Reviewed-by: Stefan Berger &lt;stefanb@linux.ibm.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: ecdsa - Move X9.62 signature decoding into template</title>
<updated>2024-10-05T05:22:04Z</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2024-09-10T14:30:25Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=d6793ff974e07e4eea151d1f0805e92d042825a1'/>
<id>urn:sha1:d6793ff974e07e4eea151d1f0805e92d042825a1</id>
<content type='text'>
Unlike the rsa driver, which separates signature decoding and
signature verification into two steps, the ecdsa driver does both in one.

This restricts users to the one signature format currently supported
(X9.62) and prevents addition of others such as P1363, which is needed
by the forthcoming SPDM library (Security Protocol and Data Model) for
PCI device authentication.

Per Herbert's suggestion, change ecdsa to use a "raw" signature encoding
and then implement X9.62 and P1363 as templates which convert their
respective encodings to the raw one.  One may then specify
"x962(ecdsa-nist-XXX)" or "p1363(ecdsa-nist-XXX)" to pick the encoding.

The present commit moves X9.62 decoding to a template.  A separate
commit is going to introduce another template for P1363 decoding.

The ecdsa driver internally represents a signature as two u64 arrays of
size ECC_MAX_BYTES.  This appears to be the most natural choice for the
raw format as it can directly be used for verification without having to
further decode signature data or copy it around.

Repurpose all the existing test vectors for "x962(ecdsa-nist-XXX)" and
create a duplicate of them to test the raw encoding.

Link: https://lore.kernel.org/all/ZoHXyGwRzVvYkcTP@gondor.apana.org.au/
Signed-off-by: Lukas Wunner &lt;lukas@wunner.de&gt;
Tested-by: Stefan Berger &lt;stefanb@linux.ibm.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: rsassa-pkcs1 - Migrate to sig_alg backend</title>
<updated>2024-10-05T05:22:04Z</updated>
<author>
<name>Lukas Wunner</name>
<email>lukas@wunner.de</email>
</author>
<published>2024-09-10T14:30:16Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=1e562deacecca1f1bec7d23da526904a1e87525e'/>
<id>urn:sha1:1e562deacecca1f1bec7d23da526904a1e87525e</id>
<content type='text'>
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 &lt;lukas@wunner.de&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: sm2 - Remove sm2 algorithm</title>
<updated>2024-06-07T11:46:39Z</updated>
<author>
<name>Herbert Xu</name>
<email>herbert@gondor.apana.org.au</email>
</author>
<published>2024-05-31T10:20:03Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=46b3ff73afc815f1feb844e6b57e43cc13051544'/>
<id>urn:sha1:46b3ff73afc815f1feb844e6b57e43cc13051544</id>
<content type='text'>
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 &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>Merge tag 'net-next-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next</title>
<updated>2024-05-15T02:42:24Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-05-15T02:42:24Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=1b294a1f35616977caddaddf3e9d28e576a1adbc'/>
<id>urn:sha1:1b294a1f35616977caddaddf3e9d28e576a1adbc</id>
<content type='text'>
Pull networking updates from Jakub Kicinski:
 "Core &amp; protocols:

   - Complete rework of garbage collection of AF_UNIX sockets.

     AF_UNIX is prone to forming reference count cycles due to fd
     passing functionality. New method based on Tarjan's Strongly
     Connected Components algorithm should be both faster and remove a
     lot of workarounds we accumulated over the years.

   - Add TCP fraglist GRO support, allowing chaining multiple TCP
     packets and forwarding them together. Useful for small switches /
     routers which lack basic checksum offload in some scenarios (e.g.
     PPPoE).

   - Support using SMP threads for handling packet backlog i.e. packet
     processing from software interfaces and old drivers which don't use
     NAPI. This helps move the processing out of the softirq jumble.

   - Continue work of converting from rtnl lock to RCU protection.

     Don't require rtnl lock when reading: IPv6 routing FIB, IPv6
     address labels, netdev threaded NAPI sysfs files, bonding driver's
     sysfs files, MPLS devconf, IPv4 FIB rules, netns IDs, tcp metrics,
     TC Qdiscs, neighbor entries, ARP entries via ioctl(SIOCGARP), a lot
     of the link information available via rtnetlink.

   - Small optimizations from Eric to UDP wake up handling, memory
     accounting, RPS/RFS implementation, TCP packet sizing etc.

   - Allow direct page recycling in the bulk API used by XDP, for +2%
     PPS.

   - Support peek with an offset on TCP sockets.

   - Add MPTCP APIs for querying last time packets were received/sent/acked
     and whether MPTCP "upgrade" succeeded on a TCP socket.

   - Add intra-node communication shortcut to improve SMC performance.

   - Add IPv6 (and IPv{4,6}-over-IPv{4,6}) support to the GTP protocol
     driver.

   - Add HSR-SAN (RedBOX) mode of operation to the HSR protocol driver.

   - Add reset reasons for tracing what caused a TCP reset to be sent.

   - Introduce direction attribute for xfrm (IPSec) states. State can be
     used either for input or output packet processing.

  Things we sprinkled into general kernel code:

   - Add bitmap_{read,write}(), bitmap_size(), expose BYTES_TO_BITS().

     This required touch-ups and renaming of a few existing users.

   - Add Endian-dependent __counted_by_{le,be} annotations.

   - Make building selftests "quieter" by printing summaries like
     "CC object.o" rather than full commands with all the arguments.

  Netfilter:

   - Use GFP_KERNEL to clone elements, to deal better with OOM
     situations and avoid failures in the .commit step.

  BPF:

   - Add eBPF JIT for ARCv2 CPUs.

   - Support attaching kprobe BPF programs through kprobe_multi link in
     a session mode, meaning, a BPF program is attached to both function
     entry and return, the entry program can decide if the return
     program gets executed and the entry program can share u64 cookie
     value with return program. "Session mode" is a common use-case for
     tetragon and bpftrace.

   - Add the ability to specify and retrieve BPF cookie for raw
     tracepoint programs in order to ease migration from classic to raw
     tracepoints.

   - Add an internal-only BPF per-CPU instruction for resolving per-CPU
     memory addresses and implement support in x86, ARM64 and RISC-V
     JITs. This allows inlining functions which need to access per-CPU
     state.

   - Optimize x86 BPF JIT's emit_mov_imm64, and add support for various
     atomics in bpf_arena which can be JITed as a single x86
     instruction. Support BPF arena on ARM64.

   - Add a new bpf_wq API for deferring events and refactor
     process-context bpf_timer code to keep common code where possible.

   - Harden the BPF verifier's and/or/xor value tracking.

   - Introduce crypto kfuncs to let BPF programs call kernel crypto
     APIs.

   - Support bpf_tail_call_static() helper for BPF programs with GCC 13.

   - Add bpf_preempt_{disable,enable}() kfuncs in order to allow a BPF
     program to have code sections where preemption is disabled.

  Driver API:

   - Skip software TC processing completely if all installed rules are
     marked as HW-only, instead of checking the HW-only flag rule by
     rule.

   - Add support for configuring PoE (Power over Ethernet), similar to
     the already existing support for PoDL (Power over Data Line)
     config.

   - Initial bits of a queue control API, for now allowing a single
     queue to be reset without disturbing packet flow to other queues.

   - Common (ethtool) statistics for hardware timestamping.

  Tests and tooling:

   - Remove the need to create a config file to run the net forwarding
     tests so that a naive "make run_tests" can exercise them.

   - Define a method of writing tests which require an external endpoint
     to communicate with (to send/receive data towards the test
     machine). Add a few such tests.

   - Create a shared code library for writing Python tests. Expose the
     YAML Netlink library from tools/ to the tests for easy Netlink
     access.

   - Move netfilter tests under net/, extend them, separate performance
     tests from correctness tests, and iron out issues found by running
     them "on every commit".

   - Refactor BPF selftests to use common network helpers.

   - Further work filling in YAML definitions of Netlink messages for:
     nftables, team driver, bonding interfaces, vlan interfaces, VF
     info, TC u32 mark, TC police action.

   - Teach Python YAML Netlink to decode attribute policies.

   - Extend the definition of the "indexed array" construct in the specs
     to cover arrays of scalars rather than just nests.

   - Add hyperlinks between definitions in generated Netlink docs.

  Drivers:

   - Make sure unsupported flower control flags are rejected by drivers,
     and make more drivers report errors directly to the application
     rather than dmesg (large number of driver changes from Asbjørn
     Sloth Tønnesen).

   - Ethernet high-speed NICs:
      - Broadcom (bnxt):
         - support multiple RSS contexts and steering traffic to them
         - support XDP metadata
         - make page pool allocations more NUMA aware
      - Intel (100G, ice, idpf):
         - extract datapath code common among Intel drivers into a library
         - use fewer resources in switchdev by sharing queues with the PF
         - add PFCP filter support
         - add Ethernet filter support
         - use a spinlock instead of HW lock in PTP clock ops
         - support 5 layer Tx scheduler topology
      - nVidia/Mellanox:
         - 800G link modes and 100G SerDes speeds
         - per-queue IRQ coalescing configuration
      - Marvell Octeon:
         - support offloading TC packet mark action

   - Ethernet NICs consumer, embedded and virtual:
      - stop lying about skb-&gt;truesize in USB Ethernet drivers, it
        messes up TCP memory calculations
      - Google cloud vNIC:
         - support changing ring size via ethtool
         - support ring reset using the queue control API
      - VirtIO net:
         - expose flow hash from RSS to XDP
         - per-queue statistics
         - add selftests
      - Synopsys (stmmac):
         - support controllers which require an RX clock signal from the
           MII bus to perform their hardware initialization
      - TI:
         - icssg_prueth: support ICSSG-based Ethernet on AM65x SR1.0 devices
         - icssg_prueth: add SW TX / RX Coalescing based on hrtimers
         - cpsw: minimal XDP support
      - Renesas (ravb):
         - support describing the MDIO bus
      - Realtek (r8169):
         - add support for RTL8168M
      - Microchip Sparx5:
         - matchall and flower actions mirred and redirect

   - Ethernet switches:
      - nVidia/Mellanox:
         - improve events processing performance
      - Marvell:
         - add support for MV88E6250 family internal PHYs
      - Microchip:
         - add DCB and DSCP mapping support for KSZ switches
         - vsc73xx: convert to PHYLINK
      - Realtek:
         - rtl8226b/rtl8221b: add C45 instances and SerDes switching

   - Many driver changes related to PHYLIB and PHYLINK deprecated API
     cleanup

   - Ethernet PHYs:
      - Add a new driver for Airoha EN8811H 2.5 Gigabit PHY.
      - micrel: lan8814: add support for PPS out and external timestamp trigger

   - WiFi:
      - Disable Wireless Extensions (WEXT) in all Wi-Fi 7 devices
        drivers. Modern devices can only be configured using nl80211.
      - mac80211/cfg80211
         - handle color change per link for WiFi 7 Multi-Link Operation
      - Intel (iwlwifi):
         - don't support puncturing in 5 GHz
         - support monitor mode on passive channels
         - BZ-W device support
         - P2P with HE/EHT support
         - re-add support for firmware API 90
         - provide channel survey information for Automatic Channel Selection
      - MediaTek (mt76):
         - mt7921 LED control
         - mt7925 EHT radiotap support
         - mt7920e PCI support
      - Qualcomm (ath11k):
         - P2P support for QCA6390, WCN6855 and QCA2066
         - support hibernation
         - ieee80211-freq-limit Device Tree property support
      - Qualcomm (ath12k):
         - refactoring in preparation of multi-link support
         - suspend and hibernation support
         - ACPI support
         - debugfs support, including dfs_simulate_radar support
      - RealTek:
         - rtw88: RTL8723CS SDIO device support
         - rtw89: RTL8922AE Wi-Fi 7 PCI device support
         - rtw89: complete features of new WiFi 7 chip 8922AE including
           BT-coexistence and Wake-on-WLAN
         - rtw89: use BIOS ACPI settings to set TX power and channels
         - rtl8xxxu: enable Management Frame Protection (MFP) support

   - Bluetooth:
      - support for Intel BlazarI and Filmore Peak2 (BE201)
      - support for MediaTek MT7921S SDIO
      - initial support for Intel PCIe BT driver
      - remove HCI_AMP support"

* tag 'net-next-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1827 commits)
  selftests: netfilter: fix packetdrill conntrack testcase
  net: gro: fix napi_gro_cb zeroed alignment
  Bluetooth: btintel_pcie: Refactor and code cleanup
  Bluetooth: btintel_pcie: Fix warning reported by sparse
  Bluetooth: hci_core: Fix not handling hdev-&gt;le_num_of_adv_sets=1
  Bluetooth: btintel: Fix compiler warning for multi_v7_defconfig config
  Bluetooth: btintel_pcie: Fix compiler warnings
  Bluetooth: btintel_pcie: Add *setup* function to download firmware
  Bluetooth: btintel_pcie: Add support for PCIe transport
  Bluetooth: btintel: Export few static functions
  Bluetooth: HCI: Remove HCI_AMP support
  Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()
  Bluetooth: qca: Fix error code in qca_read_fw_build_info()
  Bluetooth: hci_conn: Use __counted_by() and avoid -Wfamnae warning
  Bluetooth: btintel: Add support for Filmore Peak2 (BE201)
  Bluetooth: btintel: Add support for BlazarI
  LE Create Connection command timeout increased to 20 secs
  dt-bindings: net: bluetooth: Add MediaTek MT7921S SDIO Bluetooth
  Bluetooth: compute LE flow credits based on recvbuf space
  Bluetooth: hci_sync: Use cmd-&gt;num_cis instead of magic number
  ...
</content>
</entry>
<entry>
<title>bpf: crypto: add skcipher to bpf crypto</title>
<updated>2024-04-24T23:01:10Z</updated>
<author>
<name>Vadim Fedorenko</name>
<email>vadfed@meta.com</email>
</author>
<published>2024-04-22T22:50:22Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=fda4f71282b21a8cf230b656781efb0a41371fd4'/>
<id>urn:sha1:fda4f71282b21a8cf230b656781efb0a41371fd4</id>
<content type='text'>
Implement skcipher crypto in BPF crypto framework.

Signed-off-by: Vadim Fedorenko &lt;vadfed@meta.com&gt;
Acked-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
Link: https://lore.kernel.org/r/20240422225024.2847039-3-vadfed@meta.com
Signed-off-by: Martin KaFai Lau &lt;martin.lau@kernel.org&gt;
</content>
</entry>
<entry>
<title>crypto: remove CONFIG_CRYPTO_STATS</title>
<updated>2024-04-02T02:49:38Z</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2024-03-13T03:48:21Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=29ce50e078b857977202205394f200a25889636e'/>
<id>urn:sha1:29ce50e078b857977202205394f200a25889636e</id>
<content type='text'>
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&amp;literal=1&amp;perpkg=1

The patch series that added this feature in 2018
(https://lore.kernel.org/linux-crypto/1537351855-16618-1-git-send-email-clabbe@baylibre.com/)
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 &lt;ardb@kernel.org&gt;
Acked-by: Corentin Labbe &lt;clabbe@baylibre.com&gt;
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: cfb,ofb - Remove cfb and ofb</title>
<updated>2023-12-08T03:59:46Z</updated>
<author>
<name>Herbert Xu</name>
<email>herbert@gondor.apana.org.au</email>
</author>
<published>2023-11-30T12:25:02Z</published>
<link rel='alternate' type='text/html' href='https://git.kobert.dev/pm24.git/commit/?id=412ac51ce0b8c5581b6ff57fff6501e905a5471f'/>
<id>urn:sha1:412ac51ce0b8c5581b6ff57fff6501e905a5471f</id>
<content type='text'>
    
Remove the unused algorithms CFB/OFB.

Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
</feed>
