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authorLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-10-02 12:17:24 -0700
commit3f1fe48a36b0b6722dc3fd421d93512bac138e9a (patch)
treeb767d7f6e26bc64334d3f14f8422d187239dc45d /include/crypto/aes-ctr.h
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Merge tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linuxgrafted
Pull io_uring fixes from Jens Axboe: - Fix a task_work add use-after-free with SQPOLL. The sqpoll thread could pop and complete the last request while io_req_normal_work_add() was still looking at them after the mpscq push. Use the same approach as DEFER_TASKRUN to protect from that, holding an RCU read lock across the add, and have exit wait for an RCU grace period for SQPOLL rings as well. - CQE32 ring fixes: correct the free entry check for 32b CQEs, zero the big_cqe for aux CQEs, and only post the dummy skip CQE on CQE_MIXED rings - Mark the source filter table as COW when cloning bpf filters, so registering another filter on the source doesn't modify the shared table in place - Initialize the task context before running the BPF loop - Requeue zcrx multishot receives stopped by a local resource - End a TX_TIMESTAMP multishot cmd when the CQ is full (lollipopkit) * tag 'io_uring-7.3-20261002' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: io_uring: fix task_work add use-after-free with SQPOLL io_uring/cmd_net: end TX_TIMESTAMP multishot when the CQ is full io_uring/zcrx: requeue multishot receives stopped by a local resource io_uring: initialize task context before running the BPF loop io_uring: zero big_cqe for aux CQEs on CQE32 rings io_uring: fix free entry check for 32b CQEs on CQE32 rings io_uring: only post the dummy skip CQE on CQE_MIXED rings io_uring/bpf_filter: mark source as COW when cloning filters
Diffstat (limited to 'include/crypto/aes-ctr.h')
-rw-r--r--include/crypto/aes-ctr.h65
1 files changed, 65 insertions, 0 deletions
diff --git a/include/crypto/aes-ctr.h b/include/crypto/aes-ctr.h
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+++ b/include/crypto/aes-ctr.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-CTR and AES-XCTR stream ciphers
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_CTR_H
+#define _CRYPTO_AES_CTR_H
+
+#include <crypto/aes.h>
+
+/**
+ * aes_ctr() - AES-CTR en/decryption
+ * @dst: The destination buffer. Can be in-place or out-of-place. For other
+ * overlaps the behavior is unspecified.
+ * @src: The source data
+ * @len: Number of bytes to en/decrypt
+ * @ctr: The counter. It will be incremented by ceil(@len / AES_BLOCK_SIZE).
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * This implements AES in counter mode with a 128-bit big endian counter.
+ *
+ * This exists only for use by the implementation of modes built on top of CTR
+ * (e.g., GCM and CCM) and some legacy protocols that use CTR mode directly.
+ * Callers are expected to know how to use CTR mode appropriately, including
+ * choosing (key, counter) pairs appropriately to avoid keystream reuse.
+ *
+ * This supports incremental en/decryption. The length of each non-final chunk
+ * must be a multiple of AES_BLOCK_SIZE, and the updated @ctr must be passed in
+ * each time.
+ *
+ * Context: Any context.
+ */
+void aes_ctr(u8 *dst, const u8 *src, size_t len,
+ u8 ctr[at_least AES_BLOCK_SIZE], aes_encrypt_arg key);
+
+/**
+ * aes_xctr() - AES-XCTR en/decryption
+ * @dst: The destination buffer. Can be in-place or out-of-place. For other
+ * overlaps the behavior is unspecified.
+ * @src: The source data
+ * @len: Number of bytes to en/decrypt
+ * @ctr: The block counter (in host endianness). For the first call, set it to
+ * 1. It will be incremented by ceil(@len / AES_BLOCK_SIZE).
+ * @iv: The initialization vector
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * This implements AES in XOR Counter mode, as specified in the paper
+ * "Length-preserving encryption with HCTR2"
+ * (https://eprint.iacr.org/2021/1441.pdf).
+ *
+ * This exists only for use by the implementation of modes built on top of XCTR.
+ * Callers are expected to know how to use XCTR mode appropriately, including
+ * choosing (key, IV) pairs appropriately to avoid keystream reuse.
+ *
+ * This supports incremental en/decryption. The length of each non-final chunk
+ * must be a multiple of AES_BLOCK_SIZE, and the updated @ctr must be passed in
+ * each time.
+ *
+ * Context: Any context.
+ */
+void aes_xctr(u8 *dst, const u8 *src, size_t len, u64 *ctr,
+ const u8 iv[at_least AES_BLOCK_SIZE], aes_encrypt_arg key);
+
+#endif /* _CRYPTO_AES_CTR_H */