<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/drivers/crypto/qce, branch v5.9-rc6</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>crypto: drivers - set the flag CRYPTO_ALG_ALLOCATES_MEMORY</title>
<updated>2020-07-16T11:49:10+00:00</updated>
<author>
<name>Mikulas Patocka</name>
<email>mpatocka@redhat.com</email>
</author>
<published>2020-07-10T06:20:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=b8aa7dc5c7535f9abfca4bceb0ade9ee10cf5f54'/>
<id>b8aa7dc5c7535f9abfca4bceb0ade9ee10cf5f54</id>
<content type='text'>
Set the flag CRYPTO_ALG_ALLOCATES_MEMORY in the crypto drivers that
allocate memory.

drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c: sun8i_ce_cipher
drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c: sun8i_ss_cipher
drivers/crypto/amlogic/amlogic-gxl-core.c: meson_cipher
drivers/crypto/axis/artpec6_crypto.c: artpec6_crypto_common_init
drivers/crypto/bcm/cipher.c: spu_skcipher_rx_sg_create
drivers/crypto/caam/caamalg.c: aead_edesc_alloc
drivers/crypto/caam/caamalg_qi.c: aead_edesc_alloc
drivers/crypto/caam/caamalg_qi2.c: aead_edesc_alloc
drivers/crypto/caam/caamhash.c: hash_digest_key
drivers/crypto/cavium/cpt/cptvf_algs.c: process_request
drivers/crypto/cavium/nitrox/nitrox_aead.c: nitrox_process_se_request
drivers/crypto/cavium/nitrox/nitrox_skcipher.c: nitrox_process_se_request
drivers/crypto/ccp/ccp-crypto-aes-cmac.c: ccp_do_cmac_update
drivers/crypto/ccp/ccp-crypto-aes-galois.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-aes-xts.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-aes.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-des3.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-sha.c: ccp_crypto_enqueue_request
drivers/crypto/chelsio/chcr_algo.c: create_cipher_wr
drivers/crypto/hisilicon/sec/sec_algs.c: sec_alloc_and_fill_hw_sgl
drivers/crypto/hisilicon/sec2/sec_crypto.c: sec_alloc_req_id
drivers/crypto/inside-secure/safexcel_cipher.c: safexcel_queue_req
drivers/crypto/inside-secure/safexcel_hash.c: safexcel_ahash_enqueue
drivers/crypto/ixp4xx_crypto.c: ablk_perform
drivers/crypto/marvell/cesa/cipher.c: mv_cesa_skcipher_dma_req_init
drivers/crypto/marvell/cesa/hash.c: mv_cesa_ahash_dma_req_init
drivers/crypto/marvell/octeontx/otx_cptvf_algs.c: create_ctx_hdr
drivers/crypto/n2_core.c: n2_compute_chunks
drivers/crypto/picoxcell_crypto.c: spacc_sg_to_ddt
drivers/crypto/qat/qat_common/qat_algs.c: qat_alg_skcipher_encrypt
drivers/crypto/qce/skcipher.c: qce_skcipher_async_req_handle
drivers/crypto/talitos.c : talitos_edesc_alloc
drivers/crypto/virtio/virtio_crypto_algs.c: __virtio_crypto_skcipher_do_req
drivers/crypto/xilinx/zynqmp-aes-gcm.c: zynqmp_aes_aead_cipher

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
[EB: avoid overly-long lines]
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Set the flag CRYPTO_ALG_ALLOCATES_MEMORY in the crypto drivers that
allocate memory.

drivers/crypto/allwinner/sun8i-ce/sun8i-ce-core.c: sun8i_ce_cipher
drivers/crypto/allwinner/sun8i-ss/sun8i-ss-core.c: sun8i_ss_cipher
drivers/crypto/amlogic/amlogic-gxl-core.c: meson_cipher
drivers/crypto/axis/artpec6_crypto.c: artpec6_crypto_common_init
drivers/crypto/bcm/cipher.c: spu_skcipher_rx_sg_create
drivers/crypto/caam/caamalg.c: aead_edesc_alloc
drivers/crypto/caam/caamalg_qi.c: aead_edesc_alloc
drivers/crypto/caam/caamalg_qi2.c: aead_edesc_alloc
drivers/crypto/caam/caamhash.c: hash_digest_key
drivers/crypto/cavium/cpt/cptvf_algs.c: process_request
drivers/crypto/cavium/nitrox/nitrox_aead.c: nitrox_process_se_request
drivers/crypto/cavium/nitrox/nitrox_skcipher.c: nitrox_process_se_request
drivers/crypto/ccp/ccp-crypto-aes-cmac.c: ccp_do_cmac_update
drivers/crypto/ccp/ccp-crypto-aes-galois.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-aes-xts.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-aes.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-des3.c: ccp_crypto_enqueue_request
drivers/crypto/ccp/ccp-crypto-sha.c: ccp_crypto_enqueue_request
drivers/crypto/chelsio/chcr_algo.c: create_cipher_wr
drivers/crypto/hisilicon/sec/sec_algs.c: sec_alloc_and_fill_hw_sgl
drivers/crypto/hisilicon/sec2/sec_crypto.c: sec_alloc_req_id
drivers/crypto/inside-secure/safexcel_cipher.c: safexcel_queue_req
drivers/crypto/inside-secure/safexcel_hash.c: safexcel_ahash_enqueue
drivers/crypto/ixp4xx_crypto.c: ablk_perform
drivers/crypto/marvell/cesa/cipher.c: mv_cesa_skcipher_dma_req_init
drivers/crypto/marvell/cesa/hash.c: mv_cesa_ahash_dma_req_init
drivers/crypto/marvell/octeontx/otx_cptvf_algs.c: create_ctx_hdr
drivers/crypto/n2_core.c: n2_compute_chunks
drivers/crypto/picoxcell_crypto.c: spacc_sg_to_ddt
drivers/crypto/qat/qat_common/qat_algs.c: qat_alg_skcipher_encrypt
drivers/crypto/qce/skcipher.c: qce_skcipher_async_req_handle
drivers/crypto/talitos.c : talitos_edesc_alloc
drivers/crypto/virtio/virtio_crypto_algs.c: __virtio_crypto_skcipher_do_req
drivers/crypto/xilinx/zynqmp-aes-gcm.c: zynqmp_aes_aead_cipher

Signed-off-by: Mikulas Patocka &lt;mpatocka@redhat.com&gt;
[EB: avoid overly-long lines]
Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - permit asynchronous skcipher as fallback</title>
<updated>2020-07-16T11:49:03+00:00</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ardb@kernel.org</email>
</author>
<published>2020-07-07T06:32:01+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=90e2f782719fc5ad2af63096815a69c5320704cb'/>
<id>90e2f782719fc5ad2af63096815a69c5320704cb</id>
<content type='text'>
Even though the qce driver implements asynchronous versions of ecb(aes),
cbc(aes)and xts(aes), the fallbacks it allocates are required to be
synchronous. Given that SIMD based software implementations are usually
asynchronous as well, even though they rarely complete asynchronously
(this typically only happens in cases where the request was made from
softirq context, while SIMD was already in use in the task context that
it interrupted), these implementations are disregarded, and either the
generic C version or another table based version implemented in assembler
is selected instead.

Since falling back to synchronous AES is not only a performance issue, but
potentially a security issue as well (due to the fact that table based AES
is not time invariant), let's fix this, by allocating an ordinary skcipher
as the fallback, and invoke it with the completion routine that was given
to the outer request.

While at it, remove the pointless memset() from qce_skcipher_init(), and
remove the call to it qce_skcipher_init_fallback().

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Even though the qce driver implements asynchronous versions of ecb(aes),
cbc(aes)and xts(aes), the fallbacks it allocates are required to be
synchronous. Given that SIMD based software implementations are usually
asynchronous as well, even though they rarely complete asynchronously
(this typically only happens in cases where the request was made from
softirq context, while SIMD was already in use in the task context that
it interrupted), these implementations are disregarded, and either the
generic C version or another table based version implemented in assembler
is selected instead.

Since falling back to synchronous AES is not only a performance issue, but
potentially a security issue as well (due to the fact that table based AES
is not time invariant), let's fix this, by allocating an ordinary skcipher
as the fallback, and invoke it with the completion routine that was given
to the outer request.

While at it, remove the pointless memset() from qce_skcipher_init(), and
remove the call to it qce_skcipher_init_fallback().

Signed-off-by: Ard Biesheuvel &lt;ardb@kernel.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce/sha - Do not modify scatterlist passed along with request</title>
<updated>2020-07-03T04:18:34+00:00</updated>
<author>
<name>Sivaprakash Murugesan</name>
<email>sivaprak@codeaurora.org</email>
</author>
<published>2020-06-22T06:15:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=df12ef60c87b8fffc4d066dc6e553a77feaa6caf'/>
<id>df12ef60c87b8fffc4d066dc6e553a77feaa6caf</id>
<content type='text'>
Crypto test driver's test_ahash_speed calls crypto_ahash_update and
crypto_ahash_final APIs repeatedly for all the available test vector
buffer lengths.

if we mark the end for scatterlist based on the current vector size then
the subsequent vectors might fail if the later buffer lengths are higher.

To avoid this, in qce do not mark the end of scatterlist in update API,
the qce_ahash_async_req_handle API already takes care of this copying
right amount of buffer from the request scatter list.

Signed-off-by: Sivaprakash Murugesan &lt;sivaprak@codeaurora.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Crypto test driver's test_ahash_speed calls crypto_ahash_update and
crypto_ahash_final APIs repeatedly for all the available test vector
buffer lengths.

if we mark the end for scatterlist based on the current vector size then
the subsequent vectors might fail if the later buffer lengths are higher.

To avoid this, in qce do not mark the end of scatterlist in update API,
the qce_ahash_async_req_handle API already takes care of this copying
right amount of buffer from the request scatter list.

Signed-off-by: Sivaprakash Murugesan &lt;sivaprak@codeaurora.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - re-initialize context on import</title>
<updated>2020-07-03T04:18:34+00:00</updated>
<author>
<name>Sivaprakash Murugesan</name>
<email>sivaprak@codeaurora.org</email>
</author>
<published>2020-06-22T06:15:05+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=a668ee56ff028139a0926e4d2248c9a573858ba0'/>
<id>a668ee56ff028139a0926e4d2248c9a573858ba0</id>
<content type='text'>
crypto testmgr deliberately corrupts the request context while passing
vectors to the import. This is to make sure that drivers do not rely on
request but they take all the necessary input from io vec passed to it.

qce casts the request context from request parameter, since it is corrupted
the sub squent hash request fails and qce hangs.

To avoid this re-initialize request context on import. The qce import
API alreasy takes care of taking the input vectors from passed io vec.

Signed-off-by: Sivaprakash Murugesan &lt;sivaprak@codeaurora.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
crypto testmgr deliberately corrupts the request context while passing
vectors to the import. This is to make sure that drivers do not rely on
request but they take all the necessary input from io vec passed to it.

qce casts the request context from request parameter, since it is corrupted
the sub squent hash request fails and qce hangs.

To avoid this re-initialize request context on import. The qce import
API alreasy takes care of taking the input vectors from passed io vec.

Signed-off-by: Sivaprakash Murugesan &lt;sivaprak@codeaurora.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - support zero length test vectors</title>
<updated>2020-07-03T04:18:34+00:00</updated>
<author>
<name>Sivaprakash Murugesan</name>
<email>sivaprak@codeaurora.org</email>
</author>
<published>2020-06-22T06:15:04+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8ac1b9ccbfbaeacc0c33433e3e7825593bda366e'/>
<id>8ac1b9ccbfbaeacc0c33433e3e7825593bda366e</id>
<content type='text'>
crypto test module passes zero length vectors as test input to sha-1 and
sha-256. To provide correct output for these vectors, hash zero support
has been added as in other crypto drivers.

Signed-off-by: Sivaprakash Murugesan &lt;sivaprak@codeaurora.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
crypto test module passes zero length vectors as test input to sha-1 and
sha-256. To provide correct output for these vectors, hash zero support
has been added as in other crypto drivers.

Signed-off-by: Sivaprakash Murugesan &lt;sivaprak@codeaurora.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - fix wrong config symbol reference</title>
<updated>2020-03-12T12:00:13+00:00</updated>
<author>
<name>Eneas U de Queiroz</name>
<email>cotequeiroz@gmail.com</email>
</author>
<published>2020-03-04T18:24:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d069b20403d7fe5585d38d2c04b2d429fc95f3e6'/>
<id>d069b20403d7fe5585d38d2c04b2d429fc95f3e6</id>
<content type='text'>
The CONFIG_CRYPTO_DEV_QCE_SOFT_THRESHOLD symbol was renamed during
development, but the stringify reference in the parameter description
sneaked by unnoticed.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The CONFIG_CRYPTO_DEV_QCE_SOFT_THRESHOLD symbol was renamed during
development, but the stringify reference in the parameter description
sneaked by unnoticed.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - handle AES-XTS cases that qce fails</title>
<updated>2020-02-13T09:05:27+00:00</updated>
<author>
<name>Eneas U de Queiroz</name>
<email>cotequeiroz@gmail.com</email>
</author>
<published>2020-02-07T15:02:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7f19380b2cfd412dcef2facefb3f6c62788864d7'/>
<id>7f19380b2cfd412dcef2facefb3f6c62788864d7</id>
<content type='text'>
QCE hangs when presented with an AES-XTS request whose length is larger
than QCE_SECTOR_SIZE (512-bytes), and is not a multiple of it.  Let the
fallback cipher handle them.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
QCE hangs when presented with an AES-XTS request whose length is larger
than QCE_SECTOR_SIZE (512-bytes), and is not a multiple of it.  Let the
fallback cipher handle them.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - use AES fallback for small requests</title>
<updated>2020-02-13T09:05:27+00:00</updated>
<author>
<name>Eneas U de Queiroz</name>
<email>cotequeiroz@gmail.com</email>
</author>
<published>2020-02-07T15:02:26+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ce163ba0bf298f1707321ac025ef639f88e62801'/>
<id>ce163ba0bf298f1707321ac025ef639f88e62801</id>
<content type='text'>
Process small blocks using the fallback cipher, as a workaround for an
observed failure (DMA-related, apparently) when computing the GCM ghash
key.  This brings a speed gain as well, since it avoids the latency of
using the hardware engine to process small blocks.

Using software for all 16-byte requests would be enough to make GCM
work, but to increase performance, a larger threshold would be better.
Measuring the performance of supported ciphers with openssl speed,
software matches hardware at around 768-1024 bytes.

Considering the 256-bit ciphers, software is 2-3 times faster than qce
at 256-bytes, 30% faster at 512, and about even at 768-bytes.  With
128-bit keys, the break-even point would be around 1024-bytes.

This adds the 'aes_sw_max_len' parameter, to set the largest request
length processed by the software fallback.  Its default is being set to
512 bytes, a little lower than the break-even point, to balance the cost
in CPU usage.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Process small blocks using the fallback cipher, as a workaround for an
observed failure (DMA-related, apparently) when computing the GCM ghash
key.  This brings a speed gain as well, since it avoids the latency of
using the hardware engine to process small blocks.

Using software for all 16-byte requests would be enough to make GCM
work, but to increase performance, a larger threshold would be better.
Measuring the performance of supported ciphers with openssl speed,
software matches hardware at around 768-1024 bytes.

Considering the 256-bit ciphers, software is 2-3 times faster than qce
at 256-bytes, 30% faster at 512, and about even at 768-bytes.  With
128-bit keys, the break-even point would be around 1024-bytes.

This adds the 'aes_sw_max_len' parameter, to set the largest request
length processed by the software fallback.  Its default is being set to
512 bytes, a little lower than the break-even point, to balance the cost
in CPU usage.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: qce - use cryptlen when adding extra sgl</title>
<updated>2020-02-13T09:05:26+00:00</updated>
<author>
<name>Eneas U de Queiroz</name>
<email>cotequeiroz@gmail.com</email>
</author>
<published>2020-02-07T15:02:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d6364b8128439a8c0e381f80c38667de9f15eef8'/>
<id>d6364b8128439a8c0e381f80c38667de9f15eef8</id>
<content type='text'>
The qce crypto driver appends an extra entry to the dst sgl, to maintain
private state information.

When the gcm driver sends requests to the ctr skcipher, it passes the
authentication tag after the actual crypto payload, but it must not be
touched.

Commit 1336c2221bee ("crypto: qce - save a sg table slot for result
buf") limited the destination sgl to avoid overwriting the
authentication tag but it assumed the tag would be in a separate sgl
entry.

This is not always the case, so it is better to limit the length of the
destination buffer to req-&gt;cryptlen before appending the result buf.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The qce crypto driver appends an extra entry to the dst sgl, to maintain
private state information.

When the gcm driver sends requests to the ctr skcipher, it passes the
authentication tag after the actual crypto payload, but it must not be
touched.

Commit 1336c2221bee ("crypto: qce - save a sg table slot for result
buf") limited the destination sgl to avoid overwriting the
authentication tag but it assumed the tag would be in a separate sgl
entry.

This is not always the case, so it is better to limit the length of the
destination buffer to req-&gt;cryptlen before appending the result buf.

Signed-off-by: Eneas U de Queiroz &lt;cotequeiroz@gmail.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>crypto: remove CRYPTO_TFM_RES_BAD_KEY_LEN</title>
<updated>2020-01-09T03:30:53+00:00</updated>
<author>
<name>Eric Biggers</name>
<email>ebiggers@google.com</email>
</author>
<published>2019-12-31T03:19:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=674f368a952c48ede71784935a799a5205b92b6c'/>
<id>674f368a952c48ede71784935a799a5205b92b6c</id>
<content type='text'>
The CRYPTO_TFM_RES_BAD_KEY_LEN flag was apparently meant as a way to
make the -&gt;setkey() functions provide more information about errors.

However, no one actually checks for this flag, which makes it pointless.

Also, many algorithms fail to set this flag when given a bad length key.
Reviewing just the generic implementations, this is the case for
aes-fixed-time, cbcmac, echainiv, nhpoly1305, pcrypt, rfc3686, rfc4309,
rfc7539, rfc7539esp, salsa20, seqiv, and xcbc.  But there are probably
many more in arch/*/crypto/ and drivers/crypto/.

Some algorithms can even set this flag when the key is the correct
length.  For example, authenc and authencesn set it when the key payload
is malformed in any way (not just a bad length), the atmel-sha and ccree
drivers can set it if a memory allocation fails, and the chelsio driver
sets it for bad auth tag lengths, not just bad key lengths.

So even if someone actually wanted to start checking this flag (which
seems unlikely, since it's been unused for a long time), there would be
a lot of work needed to get it working correctly.  But it would probably
be much better to go back to the drawing board and just define different
return values, like -EINVAL if the key is invalid for the algorithm vs.
-EKEYREJECTED if the key was rejected by a policy like "no weak keys".
That would be much simpler, less error-prone, and easier to test.

So just remove this flag.

Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Reviewed-by: Horia Geantă &lt;horia.geanta@nxp.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
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<pre>
The CRYPTO_TFM_RES_BAD_KEY_LEN flag was apparently meant as a way to
make the -&gt;setkey() functions provide more information about errors.

However, no one actually checks for this flag, which makes it pointless.

Also, many algorithms fail to set this flag when given a bad length key.
Reviewing just the generic implementations, this is the case for
aes-fixed-time, cbcmac, echainiv, nhpoly1305, pcrypt, rfc3686, rfc4309,
rfc7539, rfc7539esp, salsa20, seqiv, and xcbc.  But there are probably
many more in arch/*/crypto/ and drivers/crypto/.

Some algorithms can even set this flag when the key is the correct
length.  For example, authenc and authencesn set it when the key payload
is malformed in any way (not just a bad length), the atmel-sha and ccree
drivers can set it if a memory allocation fails, and the chelsio driver
sets it for bad auth tag lengths, not just bad key lengths.

So even if someone actually wanted to start checking this flag (which
seems unlikely, since it's been unused for a long time), there would be
a lot of work needed to get it working correctly.  But it would probably
be much better to go back to the drawing board and just define different
return values, like -EINVAL if the key is invalid for the algorithm vs.
-EKEYREJECTED if the key was rejected by a policy like "no weak keys".
That would be much simpler, less error-prone, and easier to test.

So just remove this flag.

Signed-off-by: Eric Biggers &lt;ebiggers@google.com&gt;
Reviewed-by: Horia Geantă &lt;horia.geanta@nxp.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</pre>
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