kernel/linux.git/crypto/algif_skcipher.c, branch v7.2-rc1

crypto: af_alg - Drop support for off-CPU cryptography

2026-05-29T06:05:30+00:00

AF_ALG is deprecated and exposed to unprivileged userspace. Only use the least buggy algorithm implementations: the pure software ones. This removes one of the main advantages of AF_ALG, which is the ability to use it with off-CPU accelerators. However, using off-CPU accelerators has huge overheads, both in performance and attack surface. I have yet to see real-world, performance-critical workloads where using an accelerator via AF_ALG is actually a win over doing cryptography in userspace. If using an off-CPU accelerator really does turn out to be a win, a new API should be developed that is actually a good fit for it. Signed-off-by: Demi Marie Obenour Signed-off-by: Herbert Xu

net: Remove support for AIO on sockets

2026-05-29T06:05:30+00:00

The only user of msg->msg_iocb was AF_ALG, but that's deprecated. It can be removed entirely at the cost of only supporting synchronous operations. This doesn't break userspace, which will silently block (for a bounded amount of time) in io_submit instead of operating asynchronously. This also makes struct msghdr smaller, helping every other caller of sendmsg(). Signed-off-by: Demi Marie Obenour Acked-by: Jakub Kicinski Signed-off-by: Herbert Xu

crypto: af_alg - limit RX SG extraction by receive buffer budget

2026-04-03T00:54:14+00:00

Make af_alg_get_rsgl() limit each RX scatterlist extraction to the remaining receive buffer budget. af_alg_get_rsgl() currently uses af_alg_readable() only as a gate before extracting data into the RX scatterlist. Limit each extraction to the remaining af_alg_rcvbuf(sk) budget so that receive-side accounting matches the amount of data attached to the request. If skcipher cannot obtain enough RX space for at least one chunk while more data remains to be processed, reject the recvmsg call instead of rounding the request length down to zero. Fixes: e870456d8e7c8d57c059ea479b5aadbb55ff4c3a ("crypto: algif_skcipher - overhaul memory management") Reported-by: Yifan Wu Reported-by: Juefei Pu Co-developed-by: Yuan Tan Signed-off-by: Yuan Tan Suggested-by: Xin Liu Signed-off-by: Douya Le Signed-off-by: Ren Wei Signed-off-by: Herbert Xu

crypto: algif_aead - Revert to operating out-of-place

2026-03-31T08:11:47+00:00

This mostly reverts commit 72548b093ee3 except for the copying of the associated data. There is no benefit in operating in-place in algif_aead since the source and destination come from different mappings. Get rid of all the complexity added for in-place operation and just copy the AD directly. Fixes: 72548b093ee3 ("crypto: algif_aead - copy AAD from src to dst") Reported-by: Taeyang Lee <0wn@theori.io> Signed-off-by: Herbert Xu

crypto: Add missing MODULE_DESCRIPTION() macros

2024-05-31T09:34:56+00:00

Fix the 'make W=1' warnings: WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/cast_common.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/af_alg.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/algif_hash.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/algif_skcipher.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/ecc.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/curve25519-generic.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/xor.o WARNING: modpost: missing MODULE_DESCRIPTION() in crypto/crypto_simd.o Signed-off-by: Jeff Johnson Signed-off-by: Herbert Xu

crypto: algif_skcipher - Fix stream cipher chaining

2023-12-08T03:59:46+00:00

Unlike algif_aead which is always issued in one go (thus limiting the maximum size of the request), algif_skcipher has always allowed unlimited input data by cutting them up as necessary and feeding the fragments to the underlying algorithm one at a time. However, because of deficiencies in the API, this has been broken for most stream ciphers such as arc4 or chacha. This is because they have an internal state in addition to the IV that must be preserved in order to continue processing. Fix this by using the new skcipher state API. Signed-off-by: Herbert Xu

sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)

2023-06-24T22:50:13+00:00

Remove ->sendpage() and ->sendpage_locked(). sendmsg() with MSG_SPLICE_PAGES should be used instead. This allows multiple pages and multipage folios to be passed through. Signed-off-by: David Howells Acked-by: Marc Kleine-Budde # for net/can cc: Jens Axboe cc: Matthew Wilcox cc: linux-afs@lists.infradead.org cc: mptcp@lists.linux.dev cc: rds-devel@oss.oracle.com cc: tipc-discussion@lists.sourceforge.net cc: virtualization@lists.linux-foundation.org Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com Signed-off-by: Jakub Kicinski

crypto: af_alg: Support MSG_SPLICE_PAGES

2023-06-08T11:42:34+00:00

Make AF_ALG sendmsg() support MSG_SPLICE_PAGES. This causes pages to be spliced from the source iterator. This allows ->sendpage() to be replaced by something that can handle multiple multipage folios in a single transaction. Signed-off-by: David Howells cc: Herbert Xu cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: linux-crypto@vger.kernel.org cc: netdev@vger.kernel.org Acked-by: Herbert Xu Signed-off-by: Paolo Abeni

crypto: af_alg: Use extract_iter_to_sg() to create scatterlists

2023-06-08T11:42:34+00:00

Use extract_iter_to_sg() to decant the destination iterator into a scatterlist in af_alg_get_rsgl(). af_alg_make_sg() can then be removed. Signed-off-by: David Howells cc: Herbert Xu cc: "David S. Miller" cc: Eric Dumazet cc: Jakub Kicinski cc: Paolo Abeni cc: Jens Axboe cc: Matthew Wilcox cc: linux-crypto@vger.kernel.org cc: netdev@vger.kernel.org Acked-by: Herbert Xu Signed-off-by: Paolo Abeni

crypto: algif_skcipher - EBUSY on aio should be an error

2020-08-21T04:45:26+00:00

I removed the MAY_BACKLOG flag on the aio path a while ago but the error check still incorrectly interpreted EBUSY as success. This may cause the submitter to wait for a request that will never complete. Fixes: dad419970637 ("crypto: algif_skcipher - Do not set...") Signed-off-by: Herbert Xu