Merge tag 'libcrypto-updates-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux

Pull crypto library updates from Eric Biggers:
 "Add library APIs for most AES encryption modes that are used in the
  kernel (ECB, CBC, CBC-CTS, CTR, XCTR, XTS, GCM, CCM).

  These AES modes have many in-kernel users that are currently using the
  crypto_skcipher or crypto_aead APIs. These existing APIs are difficult
  to use and inefficient. Until now, the lack of proper library support
  for these has been the main gap in the crypto library.

  This set of changes is the next stage of addressing it:

   - Implement the new APIs on top of the existing support for
     single-block AES in the library.

   - Fully document the new APIs.

   - Migrate the only user of the old AES-GCM library API to the new,
     more flexible API; then remove the old API and its implementation.

   - Wire up the new APIs to the traditional crypto API by adding
     crypto_skcipher and crypto_aead algorithms.

     This makes the new APIs be covered by the traditional crypto API's
     self-tests. It also makes them be already used for real on systems
     that don't have architecture-optimized code for these modes.

     But most importantly, this is a prerequisite for migrating the
     architecture-optimized code for these AES modes (i.e.
     arch/*/crypto/aes*) into the library, which as usual will eliminate
     a lot of redundant "glue" code.

  Note that unlike some of the other algorithms that have been migrated
  to the library, e.g. SHA-512, for these AES modes there was too much
  to get done in one cycle. Nor did it make sense to handle these modes
  one at a time, because they tend to be coupled together or depend on
  each other, especially in the architecture-optimized AES code.

  Thus, most of the benefits (reductions in lines of code, performance
  improvements, etc.) will follow in later cycles when
  architecture-optimized code is migrated into the library and users of
  crypto_skcipher and crypto_aead are updated to use the new APIs.

  The design of the new APIs was informed by writing proof-of-concept
  patches for many kernel subsystems currently accessing these same
  algorithms via crypto_skcipher or crypto_aead (patches 18-33 of
  https://lore.kernel.org/r/20260707053503.209874-1-ebiggers@kernel.org/).

  While those patches will be resent for real later, the total diffstat
  for them was negative 1905 lines. So clearly the new APIs are quite a
  bit easier to use and align better with what users actually need.

  Besides the new AES encryption APIs, there are also a few changes for
  improved AES-CMAC key and context zeroization"

* tag 'libcrypto-updates-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux:
  mac80211: fils_aead: Use __cleanup() instead of memzero_explicit()
  Bluetooth: SMP: clear the aes_cmac_key when done
  smb: clear the aes_cmac_key and aes_cmac_ctx when done
  lib/crypto: aes-cmac: Add zeroization functions
  lib/crypto: aesgcm: Remove old AES-GCM library
  x86/sev: Remove obsolete virtual address check
  x86/sev: Use new AES-GCM library
  crypto: aes - Add CCM support using library
  crypto: aes - Add GCM support using library
  crypto: aes - Add XTS support using library
  crypto: aes - Add CTR and XCTR support using library
  crypto: aes - Add CBC and CBC-CTS support using library
  crypto: aes - Add ECB support using library
  lib/crypto: aes: Add CCM support
  lib/crypto: aes: Add GCM support
  lib/crypto: aes: Add XTS support
  lib/crypto: aes: Add CTR and XCTR support
  lib/crypto: aes: Add CBC and CBC-CTS support
  lib/crypto: aes: Add ECB support
  crypto: xts - Split out __xts_verify_key() helper

9 files changed, 861 insertions, 27 deletions

diff --git a/include/crypto/aes-cbc-macs.h b/include/crypto/aes-cbc-macs.h
index e61df108b926..06e8a22f8a0a 100644
--- a/include/crypto/aes-cbc-macs.h
+++ b/include/crypto/aes-cbc-macs.h
@@ -8,6 +8,7 @@
 #define _CRYPTO_AES_CBC_MACS_H
 
 #include <crypto/aes.h>
+#include <linux/string.h>
 
 /**
  * struct aes_cmac_key - Prepared key for AES-CMAC or AES-XCBC-MAC
@@ -25,6 +26,19 @@ struct aes_cmac_key {
 };
 
 /**
+ * aes_cmac_zeroize_key() - Zeroize an aes_cmac_key structure
+ * @key: The location of the key structure that should be zeroized
+ *
+ * Explicitly fills the aes_cmac_key with zeroes. This should be done once
+ * the key is not required anymore to avoid that its contents are leaked
+ * on the stack or heap (if not using kfree_sensitive()).
+ */
+static inline void aes_cmac_zeroize_key(struct aes_cmac_key *key)
+{
+	memzero_explicit(key, sizeof(*key));
+}
+
+/**
  * struct aes_cmac_ctx - Context for computing an AES-CMAC or AES-XCBC-MAC value
  * @key: Pointer to the key struct.  A pointer is used rather than a copy of the
  *	 struct, since the key struct size may be large.  It is assumed that the
@@ -41,12 +55,29 @@ struct aes_cmac_ctx {
 };
 
 /**
+ * aes_cmac_zeroize_ctx() - Zeroize an aes_cmac_ctx structure
+ * @ctx: The location of the context that should be zeroized
+ *
+ * Explicitly fills the aes_cmac_ctx with zeroes. This should be done once
+ * the context is not required anymore to avoid that its contents are
+ * leaked on the stack or heap. Only required if not using aes_cmac_final().
+ */
+static inline void aes_cmac_zeroize_ctx(struct aes_cmac_ctx *ctx)
+{
+	memzero_explicit(ctx, sizeof(*ctx));
+}
+
+/**
  * aes_cmac_preparekey() - Prepare a key for AES-CMAC
  * @key: (output) The key struct to initialize
  * @in_key: The raw AES key
  * @key_len: Length of the raw key in bytes.  The supported values are
  *	     AES_KEYSIZE_128, AES_KEYSIZE_192, and AES_KEYSIZE_256.
  *
+ * On success, the caller should ensure that the prepared key is zeroized
+ * at the end of its lifetime, e.g. by calling aes_cmac_zeroize_key() or
+ * kfree_sensitive().
+ *
  * Context: Any context.
  * Return: 0 on success or -EINVAL if the given key length is invalid.  No other
  *	   errors are possible, so callers that always pass a valid key length
@@ -79,6 +110,9 @@ void aes_xcbcmac_preparekey(struct aes_cmac_key *key,
  *
  * This supports both AES-CMAC and AES-XCBC-MAC.  Which one is done depends on
  * whether aes_cmac_preparekey() or aes_xcbcmac_preparekey() was called.
+ *
+ * The caller should ensure that the context is zeroized at the end of its
+ * lifetime, e.g. by calling aes_cmac_final() or aes_cmac_zeroize_ctx().
  */
 static inline void aes_cmac_init(struct aes_cmac_ctx *ctx,
 				 const struct aes_cmac_key *key)
diff --git a/include/crypto/aes-cbc.h b/include/crypto/aes-cbc.h
new file mode 100644
index 000000000000..7bae340935f9
--- /dev/null
+++ b/include/crypto/aes-cbc.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-CBC and AES-CBC-CTS unauthenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_CBC_H
+#define _CRYPTO_AES_CBC_H
+
+#include <crypto/aes.h>
+
+/**
+ * aes_cbc_encrypt() - Encrypt data using AES-CBC
+ * @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 encrypt.  Must be a multiple of AES_BLOCK_SIZE.
+ * @iv: The initialization vector.  It is updated with the next value, i.e. the
+ *	last ciphertext block (or left unchanged if @len == 0).
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * This supports incremental encryption.  The length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE, and the updated @iv must be passed in each time.
+ *
+ * Context: Any context.
+ */
+void aes_cbc_encrypt(u8 *dst, const u8 *src, size_t len,
+		     u8 iv[at_least AES_BLOCK_SIZE], aes_encrypt_arg key);
+
+/**
+ * aes_cbc_decrypt() - Decrypt data using AES-CBC
+ * @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 decrypt.  Must be a multiple of AES_BLOCK_SIZE.
+ * @iv: The initialization vector.  It is updated with the next value, i.e. the
+ *	last ciphertext block (or left unchanged if @len == 0).
+ * @key: The key, already prepared using aes_preparekey()
+ *
+ * This supports incremental decryption.  The length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE, and the updated @iv must be passed in each time.
+ *
+ * Context: Any context.
+ */
+void aes_cbc_decrypt(u8 *dst, const u8 *src, size_t len,
+		     u8 iv[at_least AES_BLOCK_SIZE], const struct aes_key *key);
+
+/**
+ * aes_cbc_cts_encrypt() - Encrypt data using AES-CBC-CTS (CS3 variant)
+ * @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 encrypt, at least AES_BLOCK_SIZE
+ * @iv: The initialization vector, clobbered by this function
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * Context: Any context.
+ */
+void aes_cbc_cts_encrypt(u8 *dst, const u8 *src, size_t len,
+			 u8 iv[at_least AES_BLOCK_SIZE], aes_encrypt_arg key);
+
+/**
+ * aes_cbc_cts_decrypt() - Decrypt data using AES-CBC-CTS (CS3 variant)
+ * @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 decrypt, at least AES_BLOCK_SIZE
+ * @iv: The initialization vector, clobbered by this function
+ * @key: The key, already prepared using aes_preparekey()
+ *
+ * Context: Any context.
+ */
+void aes_cbc_cts_decrypt(u8 *dst, const u8 *src, size_t len,
+			 u8 iv[at_least AES_BLOCK_SIZE],
+			 const struct aes_key *key);
+
+#endif /* _CRYPTO_AES_CBC_H */
diff --git a/include/crypto/aes-ccm.h b/include/crypto/aes-ccm.h
new file mode 100644
index 000000000000..8b00859ac4d6
--- /dev/null
+++ b/include/crypto/aes-ccm.h
@@ -0,0 +1,266 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-CCM authenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_CCM_H
+#define _CRYPTO_AES_CCM_H
+
+#include <crypto/aes.h>
+
+/**
+ * struct aes_ccm_key - A key prepared for AES-CCM encryption and decryption
+ */
+struct aes_ccm_key {
+	/* private: */
+	struct aes_enckey aes;
+	size_t authtag_len; /* Length of authentication tags in bytes */
+};
+
+/**
+ * struct aes_ccm_ctx - Context for incrementally en/decrypting a message
+ */
+struct aes_ccm_ctx {
+	/* private: */
+	/*
+	 * Pointer to the key, which is assumed to live at least as long as this
+	 * struct.
+	 */
+	const struct aes_ccm_key *key;
+	/*
+	 * The current CBC-MAC chaining value.  When not on a block boundary,
+	 * the partial block has been XOR'ed into this.  The number of partial
+	 * bytes is 'partial_len'.
+	 */
+	u8 mac[AES_BLOCK_SIZE] __aligned(__alignof__(__be64));
+	/* The current counter, a 128-bit big endian value */
+	u8 ctr[AES_BLOCK_SIZE] __aligned(__alignof__(__be64));
+	/* Buffered keystream for partial block updates */
+	u8 keystream[AES_BLOCK_SIZE] __aligned(__alignof__(__be64));
+	/* Encrypted counter of 0.  This gets XOR'ed with the tag at the end. */
+	u8 s0[AES_BLOCK_SIZE] __aligned(__alignof__(__be64));
+	/* Number of associated data bytes remaining to be provided */
+	u64 ad_remaining;
+	/* Number of en/decrypted data bytes remaining to be provided */
+	u64 data_remaining;
+	/* Current partial block length, 0 <= partial_len < AES_BLOCK_SIZE */
+	u32 partial_len;
+	/* True if associated data padding has been done */
+	bool ad_padded;
+};
+
+/**
+ * aes_ccm_preparekey() - Prepare a key for AES-CCM encryption and decryption
+ * @key: (output) The key structure to initialize
+ * @in_key: The raw AES-CCM key
+ * @key_len: Length of the raw key in bytes: 16, 24, or 32
+ * @authtag_len: Length of the authentication tag in bytes:
+ *		 4, 6, 8, 10, 12, 14, or 16.  16 is recommended.
+ *
+ * Users should use memzero_explicit() to zeroize the key struct at the end of
+ * its lifetime.  (But if this function fails, zeroization is unnecessary.)
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success
+ * * -EINVAL if either of the lengths is invalid
+ */
+int __must_check aes_ccm_preparekey(struct aes_ccm_key *key, const u8 *in_key,
+				    size_t key_len, size_t authtag_len);
+
+/**
+ * aes_ccm_encrypt() - Encrypt a message with AES-CCM
+ * @dst: The destination ciphertext data.  Can be in-place or out-of-place.
+ *	 For other overlaps the behavior is unspecified.
+ * @src: The source plaintext data
+ * @data_len: Length of plaintext in bytes (and ciphertext excluding the tag):
+ *	      at most 2^(120 - (8 * @nonce_len)) - 1
+ * @authtag: The output authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_ccm_preparekey().  Usually protocols using AES-CCM
+ *	     put the tag at the end of the ciphertext, in which case this should
+ *	     be set to @dst + @data_len and @dst must have room for the tag.
+ * @ad: The associated data
+ * @ad_len: Length of associated data in bytes
+ * @nonce: The nonce.  All (key, nonce) pairs used MUST be distinct.
+ * @nonce_len: Length of the nonce in bytes: between 7 and 13 inclusive
+ * @key: The key, already prepared using aes_ccm_preparekey()
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success
+ * * -EINVAL if @nonce_len is invalid
+ * * -EOVERFLOW if @data_len is too large for the selected @nonce_len
+ */
+int __must_check aes_ccm_encrypt(u8 *dst, const u8 *src, size_t data_len,
+				 u8 *authtag, const u8 *ad, size_t ad_len,
+				 const u8 *nonce, size_t nonce_len,
+				 const struct aes_ccm_key *key);
+
+/**
+ * aes_ccm_decrypt() - Decrypt a message with AES-CCM
+ * @dst: The destination plaintext data.  Can be in-place or out-of-place.
+ *	 For other overlaps the behavior is unspecified.
+ * @src: The source ciphertext data
+ * @data_len: Length of plaintext in bytes (and ciphertext excluding the tag):
+ *	      at most 2^(120 - (8 * @nonce_len)) - 1
+ * @authtag: The stored authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_ccm_preparekey().  Usually protocols using AES-CCM
+ *	     put the tag at the end of the ciphertext, in which case this should
+ *	     be set to @src + @data_len and @src must have room for the tag.
+ * @ad: The associated data
+ * @ad_len: Length of associated data in bytes
+ * @nonce: The nonce
+ * @nonce_len: Length of the nonce in bytes: between 7 and 13 inclusive
+ * @key: The key, already prepared using aes_ccm_preparekey()
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success.  This is the only case where any decrypted or associated data
+ *   can be used.
+ * * -EBADMSG if the message is inauthentic
+ * * -EINVAL if @nonce_len is invalid
+ * * -EOVERFLOW if @data_len is too large for the selected @nonce_len
+ */
+int __must_check aes_ccm_decrypt(u8 *dst, const u8 *src, size_t data_len,
+				 const u8 *authtag, const u8 *ad, size_t ad_len,
+				 const u8 *nonce, size_t nonce_len,
+				 const struct aes_ccm_key *key);
+
+/**
+ * aes_ccm_init() - Initialize context for incremental AES-CCM encryption or
+ *		    decryption
+ * @ctx: The context to initialize
+ * @data_len: Length of the en/decrypted data that will be provided in bytes:
+ *	      at most 2^(120 - (8 * @nonce_len)) - 1
+ * @ad_len: Length of the associated data that will be provided in bytes
+ * @nonce: The nonce.  All (key, nonce) pairs used for encryption MUST be
+ *	   distinct.
+ * @nonce_len: Length of the nonce in bytes: between 7 and 13 inclusive
+ * @key: The key, already prepared using aes_ccm_preparekey().  Note that a
+ *	 pointer to the key is saved in the context, so the key must live at
+ *	 least as long as the context.
+ *
+ * Unlike AES-GCM, AES-CCM requires the total lengths of the associated data and
+ * the en/decrypted data to be known during initialization.  Callers MUST ensure
+ * that these lengths are correct.
+ *
+ * If this function returns success, the context should be zeroized at the end
+ * of its lifetime.  Normally that happens in aes_ccm_encrypt_final() or
+ * aes_ccm_decrypt_final(), but callers that abandon a context without
+ * finalizing it should explicitly zeroize it.
+ *
+ * IMPORTANT: Callers that are decrypting MUST NOT assume that any decrypted or
+ * associated data is authentic until the authentication tag has been verified.
+ * This incremental API is provided solely to support callers that can't
+ * efficiently use the one-shot functions due to using a nonlinear data layout.
+ *
+ * For incremental AES-CCM encryption, use:
+ *
+ * 1. aes_ccm_init()
+ * 2. aes_ccm_auth_update() (any number of times)
+ * 3. aes_ccm_encrypt_update() (any number of times)
+ * 4. aes_ccm_encrypt_final()
+ *
+ * For incremental AES-CCM decryption, use:
+ *
+ * 1. aes_ccm_init()
+ * 2. aes_ccm_auth_update() (any number of times)
+ * 3. aes_ccm_decrypt_update() (any number of times)
+ * 4. aes_ccm_decrypt_final()
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success
+ * * -EINVAL if @nonce_len is invalid
+ * * -EOVERFLOW if @data_len is too large for the selected @nonce_len
+ */
+int __must_check aes_ccm_init(struct aes_ccm_ctx *ctx, u64 data_len, u64 ad_len,
+			      const u8 *nonce, size_t nonce_len,
+			      const struct aes_ccm_key *key);
+
+/**
+ * aes_ccm_auth_update() - Incrementally process AES-CCM associated data
+ * @ctx: An AES-CCM context
+ * @ad: The associated data
+ * @len: Length of the associated data in bytes
+ *
+ * IMPORTANT: Callers MUST NOT assume that any decrypted or associated data is
+ * authentic until the authentication tag has been verified.
+ *
+ * The total length of the associated data (over all calls to this function)
+ * MUST match the ad_len that was passed to aes_ccm_init().
+ *
+ * Context: Any context.
+ */
+void aes_ccm_auth_update(struct aes_ccm_ctx *ctx, const u8 *ad, size_t len);
+
+/**
+ * aes_ccm_encrypt_update() - Incrementally encrypt data with AES-CCM
+ * @ctx: An AES-CCM context
+ * @dst: The destination buffer.  Can be in-place or out-of-place.  For other
+ *	 overlaps the behavior is unspecified.
+ * @src: The source plaintext data
+ * @len: Number of bytes to encrypt
+ *
+ * This can be called only after all associated data has been processed.
+ *
+ * The total length of the encrypted data (over all calls to this function) MUST
+ * match the data_len that was passed to aes_ccm_init().
+ *
+ * Context: Any context.
+ */
+void aes_ccm_encrypt_update(struct aes_ccm_ctx *ctx, u8 *dst, const u8 *src,
+			    size_t len);
+
+/**
+ * aes_ccm_decrypt_update() - Incrementally decrypt data with AES-CCM
+ * @ctx: An AES-CCM context
+ * @dst: The destination buffer.  Can be in-place or out-of-place.  For other
+ *	 overlaps the behavior is unspecified.
+ * @src: The source ciphertext data (not including auth tag)
+ * @len: Number of bytes to decrypt
+ *
+ * This can be called only after all associated data has been processed.
+ *
+ * The total length of the decrypted data (over all calls to this function) MUST
+ * match the data_len that was passed to aes_ccm_init().
+ *
+ * IMPORTANT: Callers MUST NOT assume that any decrypted or associated data is
+ * authentic until the authentication tag has been verified.
+ *
+ * Context: Any context.
+ */
+void aes_ccm_decrypt_update(struct aes_ccm_ctx *ctx, u8 *dst, const u8 *src,
+			    size_t len);
+
+/**
+ * aes_ccm_encrypt_final() - Finish encrypting a message with AES-CCM
+ * @ctx: An AES-CCM context
+ * @authtag: The output authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_ccm_preparekey().
+ *
+ * This also zeroizes @ctx, so the caller doesn't need to do it.
+ *
+ * Context: Any context.
+ */
+void aes_ccm_encrypt_final(struct aes_ccm_ctx *ctx, u8 *authtag);
+
+/**
+ * aes_ccm_decrypt_final() - Finish decrypting a message with AES-CCM
+ * @ctx: An AES-CCM context
+ * @authtag: The stored authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_ccm_preparekey().
+ *
+ * This also zeroizes @ctx, so the caller doesn't need to do it.
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success.  This is the only case where any decrypted or associated data
+ *   can be used.
+ * * -EBADMSG if the message is inauthentic
+ */
+int __must_check aes_ccm_decrypt_final(struct aes_ccm_ctx *ctx,
+				       const u8 *authtag);
+
+#endif /* _CRYPTO_AES_CCM_H */
diff --git a/include/crypto/aes-ctr.h b/include/crypto/aes-ctr.h
new file mode 100644
index 000000000000..8e214a85716b
--- /dev/null
+++ b/include/crypto/aes-ctr.h
@@ -0,0 +1,65 @@
+/* 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 */
diff --git a/include/crypto/aes-ecb.h b/include/crypto/aes-ecb.h
new file mode 100644
index 000000000000..8cac1f8794c7
--- /dev/null
+++ b/include/crypto/aes-ecb.h
@@ -0,0 +1,49 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-ECB unauthenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_ECB_H
+#define _CRYPTO_AES_ECB_H
+
+#include <crypto/aes.h>
+
+/**
+ * aes_ecb_encrypt() - Encrypt data using AES-ECB
+ * @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 encrypt.  Must be a multiple of AES_BLOCK_SIZE.
+ * @key: The key, already prepared using aes_preparekey() or aes_prepareenckey()
+ *
+ * ECB mode is insecure by itself.  This function exists only for compatibility
+ * with legacy protocols and for internal use by other modes.
+ *
+ * This supports incremental encryption, but the length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE.
+ *
+ * Context: Any context.
+ */
+void aes_ecb_encrypt(u8 *dst, const u8 *src, size_t len, aes_encrypt_arg key);
+
+/**
+ * aes_ecb_decrypt() - Decrypt data using AES-ECB
+ * @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 decrypt.  Must be a multiple of AES_BLOCK_SIZE.
+ * @key: The key, already prepared using aes_preparekey()
+ *
+ * ECB mode is insecure by itself.  This function exists only for compatibility
+ * with legacy protocols and for internal use by other modes.
+ *
+ * This supports incremental decryption, but the length of each chunk must be a
+ * multiple of AES_BLOCK_SIZE.
+ *
+ * Context: Any context.
+ */
+void aes_ecb_decrypt(u8 *dst, const u8 *src, size_t len,
+		     const struct aes_key *key);
+
+#endif /* _CRYPTO_AES_ECB_H */
diff --git a/include/crypto/aes-gcm.h b/include/crypto/aes-gcm.h
new file mode 100644
index 000000000000..2aee62f01989
--- /dev/null
+++ b/include/crypto/aes-gcm.h
@@ -0,0 +1,260 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-GCM authenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_GCM_H
+#define _CRYPTO_AES_GCM_H
+
+#include <crypto/aes.h>
+#include <crypto/gcm.h>
+#include <crypto/gf128hash.h>
+
+/**
+ * struct aes_gcm_key - A key prepared for AES-GCM encryption and decryption
+ */
+struct aes_gcm_key {
+	/* private: */
+	struct aes_enckey aes;
+	struct ghash_key ghash;
+	size_t authtag_len; /* Length of authentication tags in bytes */
+};
+
+/**
+ * struct aes_gcm_ctx - Context for incrementally en/decrypting a message
+ */
+struct aes_gcm_ctx {
+	/* private: */
+	/*
+	 * Pointer to the key, which is assumed to live at least as long as this
+	 * struct.
+	 */
+	const struct aes_gcm_key *key;
+	/* The current GHASH context */
+	struct ghash_ctx ghash;
+	/*
+	 * The current counter.  This can be viewed as either a 128-bit big
+	 * endian counter, or as a 96-bit nonce followed by a 32-bit big endian
+	 * counter; it doesn't matter, since the last 32-bit word starts at 1,
+	 * and AES-GCM is undefined for messages that would overflow that part.
+	 * In practice this means that code optimized for AES-GCM can just
+	 * increment the last 32-bit word (wrapping at 2^32), but when needed it
+	 * can still call AES-CTR code that does a 128-bit increment.
+	 *
+	 * 'long' alignment is for crypto_xor() to work more efficiently.
+	 */
+	union {
+		u8 ctr[AES_BLOCK_SIZE];
+		__be32 ctr32[AES_BLOCK_SIZE / 4];
+	} __aligned(__alignof__(long));
+	/* Buffered keystream for partial block updates */
+	u8 keystream[AES_BLOCK_SIZE] __aligned(__alignof__(long));
+	/* Encrypted counter of 1.  This gets XOR'ed with the tag at the end. */
+	u8 j0_enc[AES_BLOCK_SIZE] __aligned(__alignof__(long));
+	/* Number of associated data bytes processed so far */
+	u64 ad_len;
+	/* Number of en/decrypted bytes processed so far */
+	u64 data_len;
+};
+
+/**
+ * aes_gcm_preparekey() - Prepare a key for AES-GCM encryption and decryption
+ * @key: (output) The key structure to initialize
+ * @in_key: The raw AES-GCM key
+ * @key_len: Length of the raw key in bytes: 16, 24, or 32
+ * @authtag_len: Length of the authentication tag in bytes:
+ *		 4, 8, 12, 13, 14, 15, or 16.  16 is recommended.
+ *
+ * Users should use memzero_explicit() to zeroize the key struct at the end of
+ * its lifetime.  (But if this function fails, zeroization is unnecessary.)
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success
+ * * -EINVAL if either of the lengths is invalid
+ */
+int __must_check aes_gcm_preparekey(struct aes_gcm_key *key, const u8 *in_key,
+				    size_t key_len, size_t authtag_len);
+
+/**
+ * aes_gcm_encrypt() - Encrypt a message with AES-GCM
+ * @dst: The destination ciphertext data.  Can be in-place or out-of-place.
+ *	 For other overlaps the behavior is unspecified.
+ * @src: The source plaintext data
+ * @data_len: Length of plaintext in bytes (and ciphertext excluding the tag):
+ *	      at most 2^36 - 32
+ * @authtag: The output authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_gcm_preparekey().  Usually protocols using AES-GCM
+ *	     put the tag at the end of the ciphertext, in which case this should
+ *	     be set to @dst + @data_len and @dst must have room for the tag.
+ * @ad: The associated data
+ * @ad_len: Length of associated data in bytes: at most 2^61 - 1
+ * @nonce: The 12-byte nonce.  All (key, nonce) pairs used MUST be distinct.
+ * @key: The key, already prepared using aes_gcm_preparekey()
+ *
+ * For AES-GMAC (i.e., AES-GCM without any data en/decrypted), use dst=NULL,
+ * src=NULL, and data_len=0 to generate the AES-GMAC value.
+ *
+ * Context: Any context.
+ */
+void aes_gcm_encrypt(u8 *dst, const u8 *src, size_t data_len, u8 *authtag,
+		     const u8 *ad, size_t ad_len, const u8 nonce[at_least 12],
+		     const struct aes_gcm_key *key);
+
+/**
+ * aes_gcm_decrypt() - Decrypt a message with AES-GCM
+ * @dst: The destination plaintext data.  Can be in-place or out-of-place.
+ *	 For other overlaps the behavior is unspecified.
+ * @src: The source ciphertext data
+ * @data_len: Length of plaintext in bytes (and ciphertext excluding the tag):
+ *	      at most 2^36 - 32
+ * @authtag: The stored authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_gcm_preparekey().  Usually protocols using AES-GCM
+ *	     put the tag at the end of the ciphertext, in which case this should
+ *	     be set to @src + @data_len and @src must have room for the tag.
+ * @ad: The associated data
+ * @ad_len: Length of associated data in bytes: at most 2^61 - 1
+ * @nonce: The 12-byte nonce
+ * @key: The key, already prepared using aes_gcm_preparekey()
+ *
+ * For AES-GMAC (i.e., AES-GCM without any data en/decrypted), use dst=NULL,
+ * src=NULL, and data_len=0 to verify the AES-GMAC value.
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success.  This is the only case where any decrypted or associated data
+ *   can be used.
+ * * -EBADMSG if the message is inauthentic
+ */
+int __must_check aes_gcm_decrypt(u8 *dst, const u8 *src, size_t data_len,
+				 const u8 *authtag, const u8 *ad, size_t ad_len,
+				 const u8 nonce[at_least 12],
+				 const struct aes_gcm_key *key);
+
+/**
+ * aes_gcm_init() - Initialize context for incremental AES-GCM encryption or
+ *		    decryption, or for AES-GMAC computation
+ * @ctx: The context to initialize
+ * @nonce: The 12-byte nonce.  All (key, nonce) pairs used for encryption or MAC
+ *	   generation MUST be distinct.
+ * @key: The key, already prepared using aes_gcm_preparekey().  Note that a
+ *	 pointer to the key is saved in the context, so the key must live at
+ *	 least as long as the context.
+ *
+ * The context should be zeroized at the end of its lifetime.  Normally that
+ * happens in aes_gcm_encrypt_final() or aes_gcm_decrypt_final(), but callers
+ * that abandon a context without finalizing it should explicitly zeroize it.
+ *
+ * IMPORTANT: Callers that are decrypting data or computing a GMAC value for
+ * verification MUST NOT assume that any decrypted or associated data is
+ * authentic until the authentication tag has been verified.  This incremental
+ * API is provided solely to support callers that can't efficiently use the
+ * one-shot functions due to using a nonlinear data layout.
+ *
+ * For incremental AES-GCM encryption, use:
+ *
+ * 1. aes_gcm_init()
+ * 2. aes_gcm_auth_update() (any number of times)
+ * 3. aes_gcm_encrypt_update() (any number of times)
+ * 4. aes_gcm_encrypt_final()
+ *
+ * For incremental AES-GCM decryption, use:
+ *
+ * 1. aes_gcm_init()
+ * 2. aes_gcm_auth_update() (any number of times)
+ * 3. aes_gcm_decrypt_update() (any number of times)
+ * 4. aes_gcm_decrypt_final()
+ *
+ * AES-GMAC is just AES-GCM with zero bytes en/decrypted.  For incremental
+ * AES-GMAC computation, use:
+ *
+ * 1. aes_gcm_init()
+ * 2. aes_gcm_auth_update() (any number of times)
+ * 3. aes_gcm_encrypt_final() to return the computed tag to the caller, or
+ *    aes_gcm_decrypt_final() to directly verify the computed tag
+ *
+ * Context: Any context.
+ */
+void aes_gcm_init(struct aes_gcm_ctx *ctx, const u8 nonce[at_least 12],
+		  const struct aes_gcm_key *key);
+
+/**
+ * aes_gcm_auth_update() - Incrementally process AES-GCM associated data
+ * @ctx: An AES-GCM context
+ * @ad: The associated data
+ * @len: Number of bytes provided.  The caller must ensure that the total
+ *	 associated data length doesn't exceed GCM's limit of 2^61 - 1.
+ *
+ * IMPORTANT: Callers MUST NOT assume that any decrypted or associated data is
+ * authentic until the authentication tag has been verified.
+ *
+ * Context: Any context.
+ */
+void aes_gcm_auth_update(struct aes_gcm_ctx *ctx, const u8 *ad, size_t len);
+
+/**
+ * aes_gcm_encrypt_update() - Incrementally encrypt data with AES-GCM
+ * @ctx: An AES-GCM context
+ * @dst: The destination buffer.  Can be in-place or out-of-place.  For other
+ *	 overlaps the behavior is unspecified.
+ * @src: The source plaintext data
+ * @len: Number of bytes to encrypt.  The caller must ensure that the total
+ *	 number of bytes encrypted doesn't exceed GCM's limit of 2^36 - 32.
+ *
+ * This can be called only after all associated data has been processed.
+ *
+ * Context: Any context.
+ */
+void aes_gcm_encrypt_update(struct aes_gcm_ctx *ctx, u8 *dst, const u8 *src,
+			    size_t len);
+
+/**
+ * aes_gcm_decrypt_update() - Incrementally decrypt data with AES-GCM
+ * @ctx: An AES-GCM context
+ * @dst: The destination buffer.  Can be in-place or out-of-place.  For other
+ *	 overlaps the behavior is unspecified.
+ * @src: The source ciphertext data (not including auth tag)
+ * @len: Number of bytes to decrypt.  The caller must ensure that the total
+ *	 number of bytes decrypted doesn't exceed GCM's limit of 2^36 - 32.
+ *
+ * This can be called only after all associated data has been processed.
+ *
+ * IMPORTANT: Callers MUST NOT assume that any decrypted or associated data is
+ * authentic until the authentication tag has been verified.
+ *
+ * Context: Any context.
+ */
+void aes_gcm_decrypt_update(struct aes_gcm_ctx *ctx, u8 *dst, const u8 *src,
+			    size_t len);
+
+/**
+ * aes_gcm_encrypt_final() - Finish encrypting a message with AES-GCM
+ * @ctx: An AES-GCM context
+ * @authtag: The output authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_gcm_preparekey().
+ *
+ * This also zeroizes @ctx, so the caller doesn't need to do it.
+ *
+ * Context: Any context.
+ */
+void aes_gcm_encrypt_final(struct aes_gcm_ctx *ctx, u8 *authtag);
+
+/**
+ * aes_gcm_decrypt_final() - Finish decrypting a message with AES-GCM
+ * @ctx: An AES-GCM context
+ * @authtag: The stored authentication tag.  Length is the authtag_len that was
+ *	     passed to aes_gcm_preparekey().
+ *
+ * This also zeroizes @ctx, so the caller doesn't need to do it.
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success.  This is the only case where any decrypted or associated data
+ *   can be used.
+ * * -EBADMSG if the message is inauthentic
+ */
+int __must_check aes_gcm_decrypt_final(struct aes_gcm_ctx *ctx,
+				       const u8 *authtag);
+
+#endif /* _CRYPTO_AES_GCM_H */
diff --git a/include/crypto/aes-xts.h b/include/crypto/aes-xts.h
new file mode 100644
index 000000000000..b9e828265e58
--- /dev/null
+++ b/include/crypto/aes-xts.h
@@ -0,0 +1,94 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * AES-XTS unauthenticated encryption and decryption
+ *
+ * Copyright 2026 Google LLC
+ */
+#ifndef _CRYPTO_AES_XTS_H
+#define _CRYPTO_AES_XTS_H
+
+#include <crypto/aes.h>
+#include <crypto/xts.h>
+
+/**
+ * struct aes_xts_key - A key prepared for AES-XTS encryption and decryption
+ *
+ * Note that (depending on the architecture) this typically is around 768 bytes,
+ * which makes it a bit too large to allocate on the stack in most cases.
+ */
+struct aes_xts_key {
+	/* private: */
+	struct aes_key main_key;
+	struct aes_enckey tweak_key;
+};
+
+/**
+ * aes_xts_preparekey() - Prepare a key for AES-XTS encryption and decryption
+ * @key: (output) The key structure to initialize
+ * @in_key: The raw AES-XTS key
+ * @key_len: Length of the raw key in bytes
+ * @flags: Optional flag XTS_FORBID_WEAK_KEYS to forbid keys whose two halves
+ *	   are the same.
+ *
+ * Users should use memzero_explicit() to zeroize the key struct at the end of
+ * its lifetime.  (But if this function fails, zeroization is unnecessary.)
+ *
+ * Context: Any context.
+ * Return:
+ * * 0 on success
+ * * -EINVAL if the key is rejected because its length isn't 32, 64, or (when
+ *   FIPS mode isn't enabled) 48; or because its two halves are the same and
+ *   either XTS_FORBID_WEAK_KEYS is given or FIPS mode is enabled.
+ */
+int __must_check aes_xts_preparekey(struct aes_xts_key *key, const u8 *in_key,
+				    size_t key_len, int flags);
+
+/**
+ * aes_xts_encrypt() - Encrypt data using AES-XTS
+ * @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 encrypt.  On non-final calls it must be a nonzero
+ *	 multiple of AES_BLOCK_SIZE.  On the final call it can be any value >=
+ *	 AES_BLOCK_SIZE, i.e. ciphertext stealing is supported.
+ * @tweak: The tweak.  It is updated with the next value, unless @len isn't a
+ *	   multiple of AES_BLOCK_SIZE in which case the value is unspecified.
+ * @key: The key, already prepared using aes_xts_preparekey()
+ * @cont: %false to begin encrypting a new message (do the tweak encryption);
+ *	  %true to continue encrypting a message (skip tweak encryption)
+ *
+ * This supports both one-shot and incremental encryption.  On the first call,
+ * pass @cont = %false.  On any later calls, pass @cont = %true and the updated
+ * @tweak; all earlier @len must have been multiples of AES_BLOCK_SIZE.
+ *
+ * Context: Any context.
+ */
+void aes_xts_encrypt(u8 *dst, const u8 *src, size_t len,
+		     u8 tweak[at_least AES_BLOCK_SIZE],
+		     const struct aes_xts_key *key, bool cont);
+
+/**
+ * aes_xts_decrypt() - Decrypt data using AES-XTS
+ * @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 decrypt.  On non-final calls it must be a nonzero
+ *	 multiple of AES_BLOCK_SIZE.  On the final call it can be any value >=
+ *	 AES_BLOCK_SIZE, i.e. ciphertext stealing is supported.
+ * @tweak: The tweak.  It is updated with the next value, unless @len isn't a
+ *	   multiple of AES_BLOCK_SIZE in which case the value is unspecified.
+ * @key: The key, already prepared using aes_xts_preparekey()
+ * @cont: %false to begin decrypting a new message (do the tweak encryption);
+ *	  %true to continue decrypting a message (skip tweak encryption)
+ *
+ * This supports both one-shot and incremental decryption.  On the first call,
+ * pass @cont = %false.  On any later calls, pass @cont = %true and the updated
+ * @tweak; all earlier @len must have been multiples of AES_BLOCK_SIZE.
+ *
+ * Context: Any context.
+ */
+void aes_xts_decrypt(u8 *dst, const u8 *src, size_t len,
+		     u8 tweak[at_least AES_BLOCK_SIZE],
+		     const struct aes_xts_key *key, bool cont);
+
+#endif /* _CRYPTO_AES_XTS_H */
diff --git a/include/crypto/gcm.h b/include/crypto/gcm.h
index 1d5f39ff1dc4..154038ca7343 100644
--- a/include/crypto/gcm.h
+++ b/include/crypto/gcm.h
@@ -3,9 +3,6 @@
 
 #include <linux/errno.h>
 
-#include <crypto/aes.h>
-#include <crypto/gf128hash.h>
-
 #define GCM_AES_IV_SIZE 12
 #define GCM_RFC4106_IV_SIZE 8
 #define GCM_RFC4543_IV_SIZE 8
@@ -13,7 +10,7 @@
 /*
  * validate authentication tag for GCM
  */
-static inline int crypto_gcm_check_authsize(unsigned int authsize)
+static inline int crypto_gcm_check_authsize(size_t authsize)
 {
 	switch (authsize) {
 	case 4:
@@ -34,7 +31,7 @@ static inline int crypto_gcm_check_authsize(unsigned int authsize)
 /*
  * validate authentication tag for RFC4106
  */
-static inline int crypto_rfc4106_check_authsize(unsigned int authsize)
+static inline int crypto_rfc4106_check_authsize(size_t authsize)
 {
 	switch (authsize) {
 	case 8:
@@ -64,22 +61,4 @@ static inline int crypto_ipsec_check_assoclen(unsigned int assoclen)
 	return 0;
 }
 
-struct aesgcm_ctx {
-	struct ghash_key	ghash_key;
-	struct aes_enckey	aes_key;
-	unsigned int		authsize;
-};
-
-int aesgcm_expandkey(struct aesgcm_ctx *ctx, const u8 *key,
-		     unsigned int keysize, unsigned int authsize);
-
-void aesgcm_encrypt(const struct aesgcm_ctx *ctx, u8 *dst, const u8 *src,
-		    int crypt_len, const u8 *assoc, int assoc_len,
-		    const u8 iv[GCM_AES_IV_SIZE], u8 *authtag);
-
-bool __must_check aesgcm_decrypt(const struct aesgcm_ctx *ctx, u8 *dst,
-				 const u8 *src, int crypt_len, const u8 *assoc,
-				 int assoc_len, const u8 iv[GCM_AES_IV_SIZE],
-				 const u8 *authtag);
-
 #endif
diff --git a/include/crypto/xts.h b/include/crypto/xts.h
index 15b16c4853d8..16aef89f021f 100644
--- a/include/crypto/xts.h
+++ b/include/crypto/xts.h
@@ -7,9 +7,9 @@
 #include <linux/fips.h>
 
 #define XTS_BLOCK_SIZE 16
+#define XTS_FORBID_WEAK_KEYS (1 << 0)
 
-static inline int xts_verify_key(struct crypto_skcipher *tfm,
-				 const u8 *key, unsigned int keylen)
+static inline int __xts_verify_key(const u8 *key, size_t keylen, int flags)
 {
 	/*
 	 * key consists of keys of equal size concatenated, therefore
@@ -29,12 +29,22 @@ static inline int xts_verify_key(struct crypto_skcipher *tfm,
 	 * Ensure that the AES and tweak key are not identical when
 	 * in FIPS mode or the FORBID_WEAK_KEYS flag is set.
 	 */
-	if ((fips_enabled || (crypto_skcipher_get_flags(tfm) &
-			      CRYPTO_TFM_REQ_FORBID_WEAK_KEYS)) &&
+	if ((fips_enabled || (flags & XTS_FORBID_WEAK_KEYS)) &&
 	    !crypto_memneq(key, key + (keylen / 2), keylen / 2))
 		return -EINVAL;
 
 	return 0;
 }
 
+static inline int xts_verify_key(struct crypto_skcipher *tfm, const u8 *key,
+				 unsigned int keylen)
+{
+	int flags = (crypto_skcipher_get_flags(tfm) &
+		     CRYPTO_TFM_REQ_FORBID_WEAK_KEYS) ?
+			    XTS_FORBID_WEAK_KEYS :
+			    0;
+
+	return __xts_verify_key(key, keylen, flags);
+}
+
 #endif  /* _CRYPTO_XTS_H */