Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 619 insertions, 0 deletions

diff --git a/crypto/adiantum.c b/crypto/adiantum.c
new file mode 100644
index 000000000..c33ba22a6
--- /dev/null
+++ b/crypto/adiantum.c
@@ -0,0 +1,619 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Adiantum length-preserving encryption mode
+ *
+ * Copyright 2018 Google LLC
+ */
+
+/*
+ * Adiantum is a tweakable, length-preserving encryption mode designed for fast
+ * and secure disk encryption, especially on CPUs without dedicated crypto
+ * instructions.  Adiantum encrypts each sector using the XChaCha12 stream
+ * cipher, two passes of an ε-almost-∆-universal (ε-∆U) hash function based on
+ * NH and Poly1305, and an invocation of the AES-256 block cipher on a single
+ * 16-byte block.  See the paper for details:
+ *
+ *	Adiantum: length-preserving encryption for entry-level processors
+ *      (https://eprint.iacr.org/2018/720.pdf)
+ *
+ * For flexibility, this implementation also allows other ciphers:
+ *
+ *	- Stream cipher: XChaCha12 or XChaCha20
+ *	- Block cipher: any with a 128-bit block size and 256-bit key
+ *
+ * This implementation doesn't currently allow other ε-∆U hash functions, i.e.
+ * HPolyC is not supported.  This is because Adiantum is ~20% faster than HPolyC
+ * but still provably as secure, and also the ε-∆U hash function of HBSH is
+ * formally defined to take two inputs (tweak, message) which makes it difficult
+ * to wrap with the crypto_shash API.  Rather, some details need to be handled
+ * here.  Nevertheless, if needed in the future, support for other ε-∆U hash
+ * functions could be added here.
+ */
+
+#include <crypto/b128ops.h>
+#include <crypto/chacha.h>
+#include <crypto/internal/cipher.h>
+#include <crypto/internal/hash.h>
+#include <crypto/internal/poly1305.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/nhpoly1305.h>
+#include <crypto/scatterwalk.h>
+#include <linux/module.h>
+
+/*
+ * Size of right-hand part of input data, in bytes; also the size of the block
+ * cipher's block size and the hash function's output.
+ */
+#define BLOCKCIPHER_BLOCK_SIZE		16
+
+/* Size of the block cipher key (K_E) in bytes */
+#define BLOCKCIPHER_KEY_SIZE		32
+
+/* Size of the hash key (K_H) in bytes */
+#define HASH_KEY_SIZE		(POLY1305_BLOCK_SIZE + NHPOLY1305_KEY_SIZE)
+
+/*
+ * The specification allows variable-length tweaks, but Linux's crypto API
+ * currently only allows algorithms to support a single length.  The "natural"
+ * tweak length for Adiantum is 16, since that fits into one Poly1305 block for
+ * the best performance.  But longer tweaks are useful for fscrypt, to avoid
+ * needing to derive per-file keys.  So instead we use two blocks, or 32 bytes.
+ */
+#define TWEAK_SIZE		32
+
+struct adiantum_instance_ctx {
+	struct crypto_skcipher_spawn streamcipher_spawn;
+	struct crypto_cipher_spawn blockcipher_spawn;
+	struct crypto_shash_spawn hash_spawn;
+};
+
+struct adiantum_tfm_ctx {
+	struct crypto_skcipher *streamcipher;
+	struct crypto_cipher *blockcipher;
+	struct crypto_shash *hash;
+	struct poly1305_core_key header_hash_key;
+};
+
+struct adiantum_request_ctx {
+
+	/*
+	 * Buffer for right-hand part of data, i.e.
+	 *
+	 *    P_L => P_M => C_M => C_R when encrypting, or
+	 *    C_R => C_M => P_M => P_L when decrypting.
+	 *
+	 * Also used to build the IV for the stream cipher.
+	 */
+	union {
+		u8 bytes[XCHACHA_IV_SIZE];
+		__le32 words[XCHACHA_IV_SIZE / sizeof(__le32)];
+		le128 bignum;	/* interpret as element of Z/(2^{128}Z) */
+	} rbuf;
+
+	bool enc; /* true if encrypting, false if decrypting */
+
+	/*
+	 * The result of the Poly1305 ε-∆U hash function applied to
+	 * (bulk length, tweak)
+	 */
+	le128 header_hash;
+
+	/* Sub-requests, must be last */
+	union {
+		struct shash_desc hash_desc;
+		struct skcipher_request streamcipher_req;
+	} u;
+};
+
+/*
+ * Given the XChaCha stream key K_S, derive the block cipher key K_E and the
+ * hash key K_H as follows:
+ *
+ *     K_E || K_H || ... = XChaCha(key=K_S, nonce=1||0^191)
+ *
+ * Note that this denotes using bits from the XChaCha keystream, which here we
+ * get indirectly by encrypting a buffer containing all 0's.
+ */
+static int adiantum_setkey(struct crypto_skcipher *tfm, const u8 *key,
+			   unsigned int keylen)
+{
+	struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+	struct {
+		u8 iv[XCHACHA_IV_SIZE];
+		u8 derived_keys[BLOCKCIPHER_KEY_SIZE + HASH_KEY_SIZE];
+		struct scatterlist sg;
+		struct crypto_wait wait;
+		struct skcipher_request req; /* must be last */
+	} *data;
+	u8 *keyp;
+	int err;
+
+	/* Set the stream cipher key (K_S) */
+	crypto_skcipher_clear_flags(tctx->streamcipher, CRYPTO_TFM_REQ_MASK);
+	crypto_skcipher_set_flags(tctx->streamcipher,
+				  crypto_skcipher_get_flags(tfm) &
+				  CRYPTO_TFM_REQ_MASK);
+	err = crypto_skcipher_setkey(tctx->streamcipher, key, keylen);
+	if (err)
+		return err;
+
+	/* Derive the subkeys */
+	data = kzalloc(sizeof(*data) +
+		       crypto_skcipher_reqsize(tctx->streamcipher), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+	data->iv[0] = 1;
+	sg_init_one(&data->sg, data->derived_keys, sizeof(data->derived_keys));
+	crypto_init_wait(&data->wait);
+	skcipher_request_set_tfm(&data->req, tctx->streamcipher);
+	skcipher_request_set_callback(&data->req, CRYPTO_TFM_REQ_MAY_SLEEP |
+						  CRYPTO_TFM_REQ_MAY_BACKLOG,
+				      crypto_req_done, &data->wait);
+	skcipher_request_set_crypt(&data->req, &data->sg, &data->sg,
+				   sizeof(data->derived_keys), data->iv);
+	err = crypto_wait_req(crypto_skcipher_encrypt(&data->req), &data->wait);
+	if (err)
+		goto out;
+	keyp = data->derived_keys;
+
+	/* Set the block cipher key (K_E) */
+	crypto_cipher_clear_flags(tctx->blockcipher, CRYPTO_TFM_REQ_MASK);
+	crypto_cipher_set_flags(tctx->blockcipher,
+				crypto_skcipher_get_flags(tfm) &
+				CRYPTO_TFM_REQ_MASK);
+	err = crypto_cipher_setkey(tctx->blockcipher, keyp,
+				   BLOCKCIPHER_KEY_SIZE);
+	if (err)
+		goto out;
+	keyp += BLOCKCIPHER_KEY_SIZE;
+
+	/* Set the hash key (K_H) */
+	poly1305_core_setkey(&tctx->header_hash_key, keyp);
+	keyp += POLY1305_BLOCK_SIZE;
+
+	crypto_shash_clear_flags(tctx->hash, CRYPTO_TFM_REQ_MASK);
+	crypto_shash_set_flags(tctx->hash, crypto_skcipher_get_flags(tfm) &
+					   CRYPTO_TFM_REQ_MASK);
+	err = crypto_shash_setkey(tctx->hash, keyp, NHPOLY1305_KEY_SIZE);
+	keyp += NHPOLY1305_KEY_SIZE;
+	WARN_ON(keyp != &data->derived_keys[ARRAY_SIZE(data->derived_keys)]);
+out:
+	kfree_sensitive(data);
+	return err;
+}
+
+/* Addition in Z/(2^{128}Z) */
+static inline void le128_add(le128 *r, const le128 *v1, const le128 *v2)
+{
+	u64 x = le64_to_cpu(v1->b);
+	u64 y = le64_to_cpu(v2->b);
+
+	r->b = cpu_to_le64(x + y);
+	r->a = cpu_to_le64(le64_to_cpu(v1->a) + le64_to_cpu(v2->a) +
+			   (x + y < x));
+}
+
+/* Subtraction in Z/(2^{128}Z) */
+static inline void le128_sub(le128 *r, const le128 *v1, const le128 *v2)
+{
+	u64 x = le64_to_cpu(v1->b);
+	u64 y = le64_to_cpu(v2->b);
+
+	r->b = cpu_to_le64(x - y);
+	r->a = cpu_to_le64(le64_to_cpu(v1->a) - le64_to_cpu(v2->a) -
+			   (x - y > x));
+}
+
+/*
+ * Apply the Poly1305 ε-∆U hash function to (bulk length, tweak) and save the
+ * result to rctx->header_hash.  This is the calculation
+ *
+ *	H_T ← Poly1305_{K_T}(bin_{128}(|L|) || T)
+ *
+ * from the procedure in section 6.4 of the Adiantum paper.  The resulting value
+ * is reused in both the first and second hash steps.  Specifically, it's added
+ * to the result of an independently keyed ε-∆U hash function (for equal length
+ * inputs only) taken over the left-hand part (the "bulk") of the message, to
+ * give the overall Adiantum hash of the (tweak, left-hand part) pair.
+ */
+static void adiantum_hash_header(struct skcipher_request *req)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+	struct adiantum_request_ctx *rctx = skcipher_request_ctx(req);
+	const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE;
+	struct {
+		__le64 message_bits;
+		__le64 padding;
+	} header = {
+		.message_bits = cpu_to_le64((u64)bulk_len * 8)
+	};
+	struct poly1305_state state;
+
+	poly1305_core_init(&state);
+
+	BUILD_BUG_ON(sizeof(header) % POLY1305_BLOCK_SIZE != 0);
+	poly1305_core_blocks(&state, &tctx->header_hash_key,
+			     &header, sizeof(header) / POLY1305_BLOCK_SIZE, 1);
+
+	BUILD_BUG_ON(TWEAK_SIZE % POLY1305_BLOCK_SIZE != 0);
+	poly1305_core_blocks(&state, &tctx->header_hash_key, req->iv,
+			     TWEAK_SIZE / POLY1305_BLOCK_SIZE, 1);
+
+	poly1305_core_emit(&state, NULL, &rctx->header_hash);
+}
+
+/* Hash the left-hand part (the "bulk") of the message using NHPoly1305 */
+static int adiantum_hash_message(struct skcipher_request *req,
+				 struct scatterlist *sgl, le128 *digest)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+	struct adiantum_request_ctx *rctx = skcipher_request_ctx(req);
+	const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE;
+	struct shash_desc *hash_desc = &rctx->u.hash_desc;
+	struct sg_mapping_iter miter;
+	unsigned int i, n;
+	int err;
+
+	hash_desc->tfm = tctx->hash;
+
+	err = crypto_shash_init(hash_desc);
+	if (err)
+		return err;
+
+	sg_miter_start(&miter, sgl, sg_nents(sgl),
+		       SG_MITER_FROM_SG | SG_MITER_ATOMIC);
+	for (i = 0; i < bulk_len; i += n) {
+		sg_miter_next(&miter);
+		n = min_t(unsigned int, miter.length, bulk_len - i);
+		err = crypto_shash_update(hash_desc, miter.addr, n);
+		if (err)
+			break;
+	}
+	sg_miter_stop(&miter);
+	if (err)
+		return err;
+
+	return crypto_shash_final(hash_desc, (u8 *)digest);
+}
+
+/* Continue Adiantum encryption/decryption after the stream cipher step */
+static int adiantum_finish(struct skcipher_request *req)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+	struct adiantum_request_ctx *rctx = skcipher_request_ctx(req);
+	const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE;
+	le128 digest;
+	int err;
+
+	/* If decrypting, decrypt C_M with the block cipher to get P_M */
+	if (!rctx->enc)
+		crypto_cipher_decrypt_one(tctx->blockcipher, rctx->rbuf.bytes,
+					  rctx->rbuf.bytes);
+
+	/*
+	 * Second hash step
+	 *	enc: C_R = C_M - H_{K_H}(T, C_L)
+	 *	dec: P_R = P_M - H_{K_H}(T, P_L)
+	 */
+	err = adiantum_hash_message(req, req->dst, &digest);
+	if (err)
+		return err;
+	le128_add(&digest, &digest, &rctx->header_hash);
+	le128_sub(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &digest);
+	scatterwalk_map_and_copy(&rctx->rbuf.bignum, req->dst,
+				 bulk_len, BLOCKCIPHER_BLOCK_SIZE, 1);
+	return 0;
+}
+
+static void adiantum_streamcipher_done(void *data, int err)
+{
+	struct skcipher_request *req = data;
+
+	if (!err)
+		err = adiantum_finish(req);
+
+	skcipher_request_complete(req, err);
+}
+
+static int adiantum_crypt(struct skcipher_request *req, bool enc)
+{
+	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
+	const struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+	struct adiantum_request_ctx *rctx = skcipher_request_ctx(req);
+	const unsigned int bulk_len = req->cryptlen - BLOCKCIPHER_BLOCK_SIZE;
+	unsigned int stream_len;
+	le128 digest;
+	int err;
+
+	if (req->cryptlen < BLOCKCIPHER_BLOCK_SIZE)
+		return -EINVAL;
+
+	rctx->enc = enc;
+
+	/*
+	 * First hash step
+	 *	enc: P_M = P_R + H_{K_H}(T, P_L)
+	 *	dec: C_M = C_R + H_{K_H}(T, C_L)
+	 */
+	adiantum_hash_header(req);
+	err = adiantum_hash_message(req, req->src, &digest);
+	if (err)
+		return err;
+	le128_add(&digest, &digest, &rctx->header_hash);
+	scatterwalk_map_and_copy(&rctx->rbuf.bignum, req->src,
+				 bulk_len, BLOCKCIPHER_BLOCK_SIZE, 0);
+	le128_add(&rctx->rbuf.bignum, &rctx->rbuf.bignum, &digest);
+
+	/* If encrypting, encrypt P_M with the block cipher to get C_M */
+	if (enc)
+		crypto_cipher_encrypt_one(tctx->blockcipher, rctx->rbuf.bytes,
+					  rctx->rbuf.bytes);
+
+	/* Initialize the rest of the XChaCha IV (first part is C_M) */
+	BUILD_BUG_ON(BLOCKCIPHER_BLOCK_SIZE != 16);
+	BUILD_BUG_ON(XCHACHA_IV_SIZE != 32);	/* nonce || stream position */
+	rctx->rbuf.words[4] = cpu_to_le32(1);
+	rctx->rbuf.words[5] = 0;
+	rctx->rbuf.words[6] = 0;
+	rctx->rbuf.words[7] = 0;
+
+	/*
+	 * XChaCha needs to be done on all the data except the last 16 bytes;
+	 * for disk encryption that usually means 4080 or 496 bytes.  But ChaCha
+	 * implementations tend to be most efficient when passed a whole number
+	 * of 64-byte ChaCha blocks, or sometimes even a multiple of 256 bytes.
+	 * And here it doesn't matter whether the last 16 bytes are written to,
+	 * as the second hash step will overwrite them.  Thus, round the XChaCha
+	 * length up to the next 64-byte boundary if possible.
+	 */
+	stream_len = bulk_len;
+	if (round_up(stream_len, CHACHA_BLOCK_SIZE) <= req->cryptlen)
+		stream_len = round_up(stream_len, CHACHA_BLOCK_SIZE);
+
+	skcipher_request_set_tfm(&rctx->u.streamcipher_req, tctx->streamcipher);
+	skcipher_request_set_crypt(&rctx->u.streamcipher_req, req->src,
+				   req->dst, stream_len, &rctx->rbuf);
+	skcipher_request_set_callback(&rctx->u.streamcipher_req,
+				      req->base.flags,
+				      adiantum_streamcipher_done, req);
+	return crypto_skcipher_encrypt(&rctx->u.streamcipher_req) ?:
+		adiantum_finish(req);
+}
+
+static int adiantum_encrypt(struct skcipher_request *req)
+{
+	return adiantum_crypt(req, true);
+}
+
+static int adiantum_decrypt(struct skcipher_request *req)
+{
+	return adiantum_crypt(req, false);
+}
+
+static int adiantum_init_tfm(struct crypto_skcipher *tfm)
+{
+	struct skcipher_instance *inst = skcipher_alg_instance(tfm);
+	struct adiantum_instance_ctx *ictx = skcipher_instance_ctx(inst);
+	struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+	struct crypto_skcipher *streamcipher;
+	struct crypto_cipher *blockcipher;
+	struct crypto_shash *hash;
+	unsigned int subreq_size;
+	int err;
+
+	streamcipher = crypto_spawn_skcipher(&ictx->streamcipher_spawn);
+	if (IS_ERR(streamcipher))
+		return PTR_ERR(streamcipher);
+
+	blockcipher = crypto_spawn_cipher(&ictx->blockcipher_spawn);
+	if (IS_ERR(blockcipher)) {
+		err = PTR_ERR(blockcipher);
+		goto err_free_streamcipher;
+	}
+
+	hash = crypto_spawn_shash(&ictx->hash_spawn);
+	if (IS_ERR(hash)) {
+		err = PTR_ERR(hash);
+		goto err_free_blockcipher;
+	}
+
+	tctx->streamcipher = streamcipher;
+	tctx->blockcipher = blockcipher;
+	tctx->hash = hash;
+
+	BUILD_BUG_ON(offsetofend(struct adiantum_request_ctx, u) !=
+		     sizeof(struct adiantum_request_ctx));
+	subreq_size = max(sizeof_field(struct adiantum_request_ctx,
+				       u.hash_desc) +
+			  crypto_shash_descsize(hash),
+			  sizeof_field(struct adiantum_request_ctx,
+				       u.streamcipher_req) +
+			  crypto_skcipher_reqsize(streamcipher));
+
+	crypto_skcipher_set_reqsize(tfm,
+				    offsetof(struct adiantum_request_ctx, u) +
+				    subreq_size);
+	return 0;
+
+err_free_blockcipher:
+	crypto_free_cipher(blockcipher);
+err_free_streamcipher:
+	crypto_free_skcipher(streamcipher);
+	return err;
+}
+
+static void adiantum_exit_tfm(struct crypto_skcipher *tfm)
+{
+	struct adiantum_tfm_ctx *tctx = crypto_skcipher_ctx(tfm);
+
+	crypto_free_skcipher(tctx->streamcipher);
+	crypto_free_cipher(tctx->blockcipher);
+	crypto_free_shash(tctx->hash);
+}
+
+static void adiantum_free_instance(struct skcipher_instance *inst)
+{
+	struct adiantum_instance_ctx *ictx = skcipher_instance_ctx(inst);
+
+	crypto_drop_skcipher(&ictx->streamcipher_spawn);
+	crypto_drop_cipher(&ictx->blockcipher_spawn);
+	crypto_drop_shash(&ictx->hash_spawn);
+	kfree(inst);
+}
+
+/*
+ * Check for a supported set of inner algorithms.
+ * See the comment at the beginning of this file.
+ */
+static bool adiantum_supported_algorithms(struct skcipher_alg *streamcipher_alg,
+					  struct crypto_alg *blockcipher_alg,
+					  struct shash_alg *hash_alg)
+{
+	if (strcmp(streamcipher_alg->base.cra_name, "xchacha12") != 0 &&
+	    strcmp(streamcipher_alg->base.cra_name, "xchacha20") != 0)
+		return false;
+
+	if (blockcipher_alg->cra_cipher.cia_min_keysize > BLOCKCIPHER_KEY_SIZE ||
+	    blockcipher_alg->cra_cipher.cia_max_keysize < BLOCKCIPHER_KEY_SIZE)
+		return false;
+	if (blockcipher_alg->cra_blocksize != BLOCKCIPHER_BLOCK_SIZE)
+		return false;
+
+	if (strcmp(hash_alg->base.cra_name, "nhpoly1305") != 0)
+		return false;
+
+	return true;
+}
+
+static int adiantum_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+	u32 mask;
+	const char *nhpoly1305_name;
+	struct skcipher_instance *inst;
+	struct adiantum_instance_ctx *ictx;
+	struct skcipher_alg *streamcipher_alg;
+	struct crypto_alg *blockcipher_alg;
+	struct shash_alg *hash_alg;
+	int err;
+
+	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
+	if (err)
+		return err;
+
+	inst = kzalloc(sizeof(*inst) + sizeof(*ictx), GFP_KERNEL);
+	if (!inst)
+		return -ENOMEM;
+	ictx = skcipher_instance_ctx(inst);
+
+	/* Stream cipher, e.g. "xchacha12" */
+	err = crypto_grab_skcipher(&ictx->streamcipher_spawn,
+				   skcipher_crypto_instance(inst),
+				   crypto_attr_alg_name(tb[1]), 0, mask);
+	if (err)
+		goto err_free_inst;
+	streamcipher_alg = crypto_spawn_skcipher_alg(&ictx->streamcipher_spawn);
+
+	/* Block cipher, e.g. "aes" */
+	err = crypto_grab_cipher(&ictx->blockcipher_spawn,
+				 skcipher_crypto_instance(inst),
+				 crypto_attr_alg_name(tb[2]), 0, mask);
+	if (err)
+		goto err_free_inst;
+	blockcipher_alg = crypto_spawn_cipher_alg(&ictx->blockcipher_spawn);
+
+	/* NHPoly1305 ε-∆U hash function */
+	nhpoly1305_name = crypto_attr_alg_name(tb[3]);
+	if (nhpoly1305_name == ERR_PTR(-ENOENT))
+		nhpoly1305_name = "nhpoly1305";
+	err = crypto_grab_shash(&ictx->hash_spawn,
+				skcipher_crypto_instance(inst),
+				nhpoly1305_name, 0, mask);
+	if (err)
+		goto err_free_inst;
+	hash_alg = crypto_spawn_shash_alg(&ictx->hash_spawn);
+
+	/* Check the set of algorithms */
+	if (!adiantum_supported_algorithms(streamcipher_alg, blockcipher_alg,
+					   hash_alg)) {
+		pr_warn("Unsupported Adiantum instantiation: (%s,%s,%s)\n",
+			streamcipher_alg->base.cra_name,
+			blockcipher_alg->cra_name, hash_alg->base.cra_name);
+		err = -EINVAL;
+		goto err_free_inst;
+	}
+
+	/* Instance fields */
+
+	err = -ENAMETOOLONG;
+	if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME,
+		     "adiantum(%s,%s)", streamcipher_alg->base.cra_name,
+		     blockcipher_alg->cra_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_free_inst;
+	if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME,
+		     "adiantum(%s,%s,%s)",
+		     streamcipher_alg->base.cra_driver_name,
+		     blockcipher_alg->cra_driver_name,
+		     hash_alg->base.cra_driver_name) >= CRYPTO_MAX_ALG_NAME)
+		goto err_free_inst;
+
+	inst->alg.base.cra_blocksize = BLOCKCIPHER_BLOCK_SIZE;
+	inst->alg.base.cra_ctxsize = sizeof(struct adiantum_tfm_ctx);
+	inst->alg.base.cra_alignmask = streamcipher_alg->base.cra_alignmask |
+				       hash_alg->base.cra_alignmask;
+	/*
+	 * The block cipher is only invoked once per message, so for long
+	 * messages (e.g. sectors for disk encryption) its performance doesn't
+	 * matter as much as that of the stream cipher and hash function.  Thus,
+	 * weigh the block cipher's ->cra_priority less.
+	 */
+	inst->alg.base.cra_priority = (4 * streamcipher_alg->base.cra_priority +
+				       2 * hash_alg->base.cra_priority +
+				       blockcipher_alg->cra_priority) / 7;
+
+	inst->alg.setkey = adiantum_setkey;
+	inst->alg.encrypt = adiantum_encrypt;
+	inst->alg.decrypt = adiantum_decrypt;
+	inst->alg.init = adiantum_init_tfm;
+	inst->alg.exit = adiantum_exit_tfm;
+	inst->alg.min_keysize = crypto_skcipher_alg_min_keysize(streamcipher_alg);
+	inst->alg.max_keysize = crypto_skcipher_alg_max_keysize(streamcipher_alg);
+	inst->alg.ivsize = TWEAK_SIZE;
+
+	inst->free = adiantum_free_instance;
+
+	err = skcipher_register_instance(tmpl, inst);
+	if (err) {
+err_free_inst:
+		adiantum_free_instance(inst);
+	}
+	return err;
+}
+
+/* adiantum(streamcipher_name, blockcipher_name [, nhpoly1305_name]) */
+static struct crypto_template adiantum_tmpl = {
+	.name = "adiantum",
+	.create = adiantum_create,
+	.module = THIS_MODULE,
+};
+
+static int __init adiantum_module_init(void)
+{
+	return crypto_register_template(&adiantum_tmpl);
+}
+
+static void __exit adiantum_module_exit(void)
+{
+	crypto_unregister_template(&adiantum_tmpl);
+}
+
+subsys_initcall(adiantum_module_init);
+module_exit(adiantum_module_exit);
+
+MODULE_DESCRIPTION("Adiantum length-preserving encryption mode");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
+MODULE_ALIAS_CRYPTO("adiantum");
+MODULE_IMPORT_NS(CRYPTO_INTERNAL);