diff mbox series

[v8,2/3] s390/crypto: New s390 specific protected key hash phmac

Message ID 20241218140530.82581-3-freude@linux.ibm.com
State New
Headers show
Series New s390 specific protected key hmac | expand

Commit Message

Harald Freudenberger Dec. 18, 2024, 2:05 p.m. UTC
Add support for protected key hmac ("phmac") for s390 arch.

With the latest machine generation there is now support for
protected key (that is a key wrapped by a master key stored
in firmware) hmac for sha2 (sha224, sha256, sha384 and sha512)
for the s390 specific CPACF instruction kmac.

This patch adds support via 4 new ahashes registered as
phmac(sha224), phmac(sha256), phmac(sha384) and phmac(sha512).

Co-developed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
---
 arch/s390/configs/debug_defconfig |   1 +
 arch/s390/configs/defconfig       |   1 +
 arch/s390/crypto/Makefile         |   1 +
 arch/s390/crypto/phmac_s390.c     | 842 ++++++++++++++++++++++++++++++
 drivers/crypto/Kconfig            |  12 +
 5 files changed, 857 insertions(+)
 create mode 100644 arch/s390/crypto/phmac_s390.c
diff mbox series

Patch

diff --git a/arch/s390/configs/debug_defconfig b/arch/s390/configs/debug_defconfig
index d8d227ab82de..c857618087fe 100644
--- a/arch/s390/configs/debug_defconfig
+++ b/arch/s390/configs/debug_defconfig
@@ -813,6 +813,7 @@  CONFIG_PKEY_EP11=m
 CONFIG_PKEY_PCKMO=m
 CONFIG_PKEY_UV=m
 CONFIG_CRYPTO_PAES_S390=m
+CONFIG_CRYPTO_PHMAC_S390=m
 CONFIG_CRYPTO_DEV_VIRTIO=m
 CONFIG_SYSTEM_BLACKLIST_KEYRING=y
 CONFIG_CORDIC=m
diff --git a/arch/s390/configs/defconfig b/arch/s390/configs/defconfig
index 6c2f2bb4fbf8..94bde39967a5 100644
--- a/arch/s390/configs/defconfig
+++ b/arch/s390/configs/defconfig
@@ -800,6 +800,7 @@  CONFIG_PKEY_EP11=m
 CONFIG_PKEY_PCKMO=m
 CONFIG_PKEY_UV=m
 CONFIG_CRYPTO_PAES_S390=m
+CONFIG_CRYPTO_PHMAC_S390=m
 CONFIG_CRYPTO_DEV_VIRTIO=m
 CONFIG_SYSTEM_BLACKLIST_KEYRING=y
 CONFIG_CORDIC=m
diff --git a/arch/s390/crypto/Makefile b/arch/s390/crypto/Makefile
index a0cb96937c3d..47637140b95c 100644
--- a/arch/s390/crypto/Makefile
+++ b/arch/s390/crypto/Makefile
@@ -16,6 +16,7 @@  obj-$(CONFIG_S390_PRNG) += prng.o
 obj-$(CONFIG_CRYPTO_GHASH_S390) += ghash_s390.o
 obj-$(CONFIG_CRYPTO_CRC32_S390) += crc32-vx_s390.o
 obj-$(CONFIG_CRYPTO_HMAC_S390) += hmac_s390.o
+obj-$(CONFIG_CRYPTO_PHMAC_S390) += phmac_s390.o
 obj-y += arch_random.o
 
 crc32-vx_s390-y := crc32-vx.o crc32le-vx.o crc32be-vx.o
diff --git a/arch/s390/crypto/phmac_s390.c b/arch/s390/crypto/phmac_s390.c
new file mode 100644
index 000000000000..34cd37524d19
--- /dev/null
+++ b/arch/s390/crypto/phmac_s390.c
@@ -0,0 +1,842 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright IBM Corp. 2024
+ *
+ * s390 specific HMAC support for protected keys.
+ */
+
+#define KMSG_COMPONENT	"phmac_s390"
+#define pr_fmt(fmt)	KMSG_COMPONENT ": " fmt
+
+#include <asm/cpacf.h>
+#include <asm/pkey.h>
+#include <crypto/cryptd.h>
+#include <crypto/internal/hash.h>
+#include <crypto/sha2.h>
+#include <linux/cpufeature.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+/*
+ * KMAC param block layout for sha2 function codes:
+ * The layout of the param block for the KMAC instruction depends on the
+ * blocksize of the used hashing sha2-algorithm function codes. The param block
+ * contains the hash chaining value (cv), the input message bit-length (imbl)
+ * and the hmac-secret (key). To prevent code duplication, the sizes of all
+ * these are calculated based on the blocksize.
+ *
+ * param-block:
+ * +-------+
+ * | cv    |
+ * +-------+
+ * | imbl  |
+ * +-------+
+ * | key   |
+ * +-------+
+ *
+ * sizes:
+ * part | sh2-alg | calculation | size | type
+ * -----+---------+-------------+------+--------
+ * cv   | 224/256 | blocksize/2 |   32 |  u64[8]
+ *      | 384/512 |             |   64 | u128[8]
+ * imbl | 224/256 | blocksize/8 |    8 |     u64
+ *      | 384/512 |             |   16 |    u128
+ * key  | 224/256 | blocksize   |   96 |  u8[96]
+ *      | 384/512 |             |  160 | u8[160]
+ */
+
+#define MAX_DIGEST_SIZE		SHA512_DIGEST_SIZE
+#define MAX_IMBL_SIZE		sizeof(u128)
+#define MAX_BLOCK_SIZE		SHA512_BLOCK_SIZE
+
+#define SHA2_CV_SIZE(bs)	((bs) >> 1)
+#define SHA2_IMBL_SIZE(bs)	((bs) >> 3)
+
+#define SHA2_IMBL_OFFSET(bs)	(SHA2_CV_SIZE(bs))
+#define SHA2_KEY_OFFSET(bs)	(SHA2_CV_SIZE(bs) + SHA2_IMBL_SIZE(bs))
+
+#define PHMAC_SHA256_KEY_SIZE	(SHA256_BLOCK_SIZE + 32)
+#define PHMAC_SHA512_KEY_SIZE	(SHA512_BLOCK_SIZE + 32)
+#define PHMAC_MAX_KEY_SIZE	PHMAC_SHA512_KEY_SIZE
+
+struct phmac_protkey {
+	u32 type;
+	u32 len;
+	u8 protkey[PHMAC_MAX_KEY_SIZE];
+};
+
+#define PK_STATE_NO_KEY		     0
+#define PK_STATE_NEEDS_CONVERT	     1
+#define PK_STATE_CONVERT_IN_PROGRESS 2
+#define PK_STATE_VALID		     3
+
+struct s390_phmac_ctx {
+	u8 *key;
+	unsigned int keylen;
+
+	/* the work struct for asynch key convert */
+	struct delayed_work work;
+
+	/* spinlock to atomic read/update the following fields */
+	spinlock_t pk_lock;
+	/* see PK_STATE* defines above, < 0 holds convert failure rc  */
+	int pk_state;
+	/* if state is valid, pk holds the protected key */
+	struct phmac_protkey pk;
+};
+
+union s390_kmac_gr0 {
+	unsigned long reg;
+	struct {
+		unsigned long		: 48;
+		unsigned long ikp	:  1;
+		unsigned long iimp	:  1;
+		unsigned long ccup	:  1;
+		unsigned long		:  6;
+		unsigned long fc	:  7;
+	};
+};
+
+struct s390_kmac_sha2_ctx {
+	u8 param[MAX_DIGEST_SIZE + MAX_IMBL_SIZE + PHMAC_MAX_KEY_SIZE];
+	union s390_kmac_gr0 gr0;
+	u8 buf[MAX_BLOCK_SIZE];
+	unsigned int buflen;
+};
+
+struct s390_phmac_req_ctx {
+	struct delayed_work work;
+	struct ahash_request *req;
+	struct s390_kmac_sha2_ctx sha2_ctx;
+};
+
+/*
+ * kmac_sha2_set_imbl - sets the input message bit-length based on the blocksize
+ */
+static inline void kmac_sha2_set_imbl(u8 *param, unsigned int buflen,
+				      unsigned int blocksize)
+{
+	u8 *imbl = param + SHA2_IMBL_OFFSET(blocksize);
+
+	switch (blocksize) {
+	case SHA256_BLOCK_SIZE:
+		*(u64 *)imbl = (u64)buflen * BITS_PER_BYTE;
+		break;
+	case SHA512_BLOCK_SIZE:
+		*(u128 *)imbl = (u128)buflen * BITS_PER_BYTE;
+		break;
+	default:
+		break;
+	}
+}
+
+/*
+ * Convert the raw key material into a protected key via PKEY api.
+ * This function may sleep - don't call in non-sleeping context.
+ */
+static int phmac_convert_key(struct s390_phmac_ctx *tfm_ctx)
+{
+	struct phmac_protkey pk;
+	int i, rc;
+
+	pk.len = sizeof(pk.protkey);
+
+	/* try three times in case of busy card */
+	for (rc = -EIO, i = 0; rc && i < 3; i++) {
+		if (rc == -EBUSY && msleep_interruptible((1 << i) * 100)) {
+			rc = -EINTR;
+			goto out;
+		}
+		rc = pkey_key2protkey(tfm_ctx->key, tfm_ctx->keylen,
+				      pk.protkey, &pk.len, &pk.type);
+	}
+	if (rc)
+		goto out;
+
+	spin_lock_bh(&tfm_ctx->pk_lock);
+	tfm_ctx->pk = pk;
+	tfm_ctx->pk_state = PK_STATE_VALID;
+	spin_unlock_bh(&tfm_ctx->pk_lock);
+
+	memzero_explicit(&pk, sizeof(pk));
+
+out:
+	pr_debug("rc=%d\n", rc);
+	return rc;
+}
+
+static void phmac_wq_convert_key_fn(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct s390_phmac_ctx *tfm_ctx =
+		container_of(dwork, struct s390_phmac_ctx, work);
+	int rc;
+
+	rc = phmac_convert_key(tfm_ctx);
+	pr_debug("asynch convert done, rc=%d\n", rc);
+}
+
+static int phmac_init(struct crypto_ahash *tfm,
+		      struct s390_kmac_sha2_ctx *ctx,
+		      bool maysleep)
+{
+	struct s390_phmac_ctx *tfm_ctx = crypto_ahash_ctx(tfm);
+	unsigned int ds = crypto_ahash_digestsize(tfm);
+	unsigned int bs = crypto_ahash_blocksize(tfm);
+	int i, rc, pk_state;
+
+	spin_lock_bh(&tfm_ctx->pk_lock);
+	pk_state = tfm_ctx->pk_state;
+	spin_unlock_bh(&tfm_ctx->pk_lock);
+
+	switch (pk_state) {
+	case PK_STATE_NO_KEY:
+		return -ENOKEY;
+	case PK_STATE_NEEDS_CONVERT:
+		if (!maysleep)
+			return -EKEYEXPIRED;
+		rc = phmac_convert_key(tfm_ctx);
+		if (rc)
+			return rc;
+		break;
+	case PK_STATE_CONVERT_IN_PROGRESS:
+		if (!maysleep)
+			return -EKEYEXPIRED;
+		for (i = 0; pk_state != PK_STATE_VALID && i < 3; i++) {
+			if (msleep_interruptible((1 << i) * 100))
+				return -EINTR;
+			spin_lock_bh(&tfm_ctx->pk_lock);
+			pk_state = tfm_ctx->pk_state;
+			spin_unlock_bh(&tfm_ctx->pk_lock);
+		}
+		if (pk_state != PK_STATE_VALID)
+			return -EKEYEXPIRED;
+		break;
+	case PK_STATE_VALID:
+		break;
+	default:
+		return pk_state < 0 ? pk_state : -EIO;
+	}
+
+	/* pk is valid, prepare the sha2 context */
+
+	spin_lock_bh(&tfm_ctx->pk_lock);
+	memcpy(ctx->param + SHA2_KEY_OFFSET(bs),
+	       tfm_ctx->pk.protkey, tfm_ctx->pk.len);
+	spin_unlock_bh(&tfm_ctx->pk_lock);
+
+	ctx->buflen = 0;
+	ctx->gr0.reg = 0;
+
+	/* set function code, check for valid protected key type */
+	rc = 0;
+	switch (ds) {
+	case SHA224_DIGEST_SIZE:
+		ctx->gr0.fc = CPACF_KMAC_PHMAC_SHA_224;
+		if (tfm_ctx->pk.type != PKEY_KEYTYPE_HMAC_512)
+			rc = -EINVAL;
+		break;
+	case SHA256_DIGEST_SIZE:
+		ctx->gr0.fc = CPACF_KMAC_PHMAC_SHA_256;
+		if (tfm_ctx->pk.type != PKEY_KEYTYPE_HMAC_512)
+			rc = -EINVAL;
+		break;
+	case SHA384_DIGEST_SIZE:
+		ctx->gr0.fc = CPACF_KMAC_PHMAC_SHA_384;
+		if (tfm_ctx->pk.type != PKEY_KEYTYPE_HMAC_1024)
+			rc = -EINVAL;
+		break;
+	case SHA512_DIGEST_SIZE:
+		ctx->gr0.fc = CPACF_KMAC_PHMAC_SHA_512;
+		if (tfm_ctx->pk.type != PKEY_KEYTYPE_HMAC_1024)
+			rc = -EINVAL;
+		break;
+	default:
+		rc = -EINVAL;
+	}
+
+	return rc;
+}
+
+static void phmac_wq_init_fn(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct s390_phmac_req_ctx *req_ctx =
+		container_of(dwork, struct s390_phmac_req_ctx, work);
+	struct ahash_request *req = req_ctx->req;
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	int rc;
+
+	rc = phmac_init(tfm, ctx, true);
+
+	pr_debug("req complete with rc=%d\n", rc);
+	crypto_request_complete(&req->base, rc);
+}
+
+static int s390_phmac_init(struct ahash_request *req)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	int rc;
+
+	/*
+	 * First try synchronous. If this fails for any reason
+	 * schedule this request asynchronous via workqueue.
+	 */
+
+	rc = phmac_init(tfm, ctx, false);
+	if (!rc)
+		goto out;
+
+	req_ctx->req = req;
+	INIT_DELAYED_WORK(&req_ctx->work, phmac_wq_init_fn);
+	schedule_delayed_work(&req_ctx->work, 0);
+	rc = -EINPROGRESS;
+
+out:
+	pr_debug("rc=%d\n", rc);
+	return rc;
+}
+
+static int phmac_update(struct crypto_ahash *tfm,
+			struct s390_kmac_sha2_ctx *ctx,
+			const u8 *data, unsigned int len,
+			bool maysleep)
+{
+	struct s390_phmac_ctx *tfm_ctx = crypto_ahash_ctx(tfm);
+	unsigned int bs = crypto_ahash_blocksize(tfm);
+	unsigned int offset, n, k;
+	int rc;
+
+	/* check current buffer */
+	offset = ctx->buflen % bs;
+	ctx->buflen += len;
+	if (offset + len < bs)
+		goto store;
+
+	/* process one stored block */
+	if (offset) {
+		n = bs - offset;
+		memcpy(ctx->buf + offset, data, n);
+		ctx->gr0.iimp = 1;
+		for (k = bs;;) {
+			k -= _cpacf_kmac(&ctx->gr0.reg, ctx->param,
+					 ctx->buf + bs - k, k);
+			if (likely(!k))
+				break;
+			if (!maysleep)
+				return -EKEYEXPIRED;
+			rc = phmac_convert_key(tfm_ctx);
+			if (rc)
+				return rc;
+			spin_lock_bh(&tfm_ctx->pk_lock);
+			memcpy(ctx->param + SHA2_KEY_OFFSET(bs),
+			       tfm_ctx->pk.protkey, tfm_ctx->pk.len);
+			spin_unlock_bh(&tfm_ctx->pk_lock);
+		}
+		data += n;
+		len -= n;
+		offset = 0;
+	}
+
+	/* process as many blocks as possible */
+	if (len >= bs) {
+		n = (len / bs) * bs;
+		ctx->gr0.iimp = 1;
+		for (k = n;;) {
+			k -= _cpacf_kmac(&ctx->gr0.reg, ctx->param,
+					 data + n - k, k);
+			if (likely(!k))
+				break;
+			if (!maysleep)
+				return -EKEYEXPIRED;
+			rc = phmac_convert_key(tfm_ctx);
+			if (rc)
+				return rc;
+			spin_lock_bh(&tfm_ctx->pk_lock);
+			memcpy(ctx->param + SHA2_KEY_OFFSET(bs),
+			       tfm_ctx->pk.protkey, tfm_ctx->pk.len);
+			spin_unlock_bh(&tfm_ctx->pk_lock);
+		}
+		data += n;
+		len -= n;
+	}
+
+store:
+	/* store incomplete block in buffer */
+	if (len)
+		memcpy(ctx->buf + offset, data, len);
+
+	return 0;
+}
+
+static void phmac_wq_update_fn(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct s390_phmac_req_ctx *req_ctx =
+		container_of(dwork, struct s390_phmac_req_ctx, work);
+	struct ahash_request *req = req_ctx->req;
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct crypto_hash_walk walk;
+	int nbytes, rc = 0;
+
+	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+	     nbytes = crypto_hash_walk_done(&walk, 0)) {
+		rc = phmac_update(tfm, ctx, walk.data, nbytes, true);
+		if (rc) {
+			crypto_hash_walk_done(&walk, rc);
+			break;
+		}
+	}
+
+	pr_debug("req complete with rc=%d\n", rc);
+	crypto_request_complete(&req->base, rc);
+}
+
+static int s390_phmac_update(struct ahash_request *req)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct s390_kmac_sha2_ctx ctx_backup;
+	struct crypto_hash_walk walk;
+	int nbytes, rc = 0;
+
+	/*
+	 * First try synchronous. If this fails for any reason
+	 * schedule this request asynchronous via workqueue.
+	 */
+
+	memcpy(&ctx_backup, ctx, sizeof(*ctx));
+
+	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+	     nbytes = crypto_hash_walk_done(&walk, 0)) {
+		rc = phmac_update(tfm, ctx, walk.data, nbytes, false);
+		if (rc) {
+			crypto_hash_walk_done(&walk, rc);
+			break;
+		}
+	}
+	if (!rc)
+		goto out;
+
+	memcpy(ctx, &ctx_backup, sizeof(*ctx));
+
+	req_ctx->req = req;
+	INIT_DELAYED_WORK(&req_ctx->work, phmac_wq_update_fn);
+	schedule_delayed_work(&req_ctx->work, 0);
+	rc = -EINPROGRESS;
+
+out:
+	pr_debug("rc=%d\n", rc);
+	return rc;
+}
+
+static int phmac_final(struct crypto_ahash *tfm,
+		       struct s390_kmac_sha2_ctx *ctx,
+		       unsigned char *result,
+		       bool maysleep)
+{
+	struct s390_phmac_ctx *tfm_ctx = crypto_ahash_ctx(tfm);
+	unsigned int ds = crypto_ahash_digestsize(tfm);
+	unsigned int bs = crypto_ahash_blocksize(tfm);
+	unsigned int n, k;
+	int rc;
+
+	n = ctx->buflen % bs;
+	ctx->gr0.iimp = 0;
+	kmac_sha2_set_imbl(ctx->param, ctx->buflen, bs);
+	for (k = n;;) {
+		k -= _cpacf_kmac(&ctx->gr0.reg, ctx->param,
+				 ctx->buf + n - k, k);
+		if (likely(!k))
+			break;
+		if (!maysleep)
+			return -EKEYEXPIRED;
+		rc = phmac_convert_key(tfm_ctx);
+		if (rc)
+			return rc;
+		spin_lock_bh(&tfm_ctx->pk_lock);
+		memcpy(ctx->param + SHA2_KEY_OFFSET(bs),
+		       tfm_ctx->pk.protkey, tfm_ctx->pk.len);
+		spin_unlock_bh(&tfm_ctx->pk_lock);
+	}
+
+	memcpy(result, ctx->param, ds);
+
+	return 0;
+}
+
+static void phmac_wq_final_fn(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct s390_phmac_req_ctx *req_ctx =
+		container_of(dwork, struct s390_phmac_req_ctx, work);
+	struct ahash_request *req = req_ctx->req;
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	int rc;
+
+	rc = phmac_final(tfm, ctx, req->result, true);
+
+	pr_debug("req complete with rc=%d\n", rc);
+	crypto_request_complete(&req->base, rc);
+}
+
+static int s390_phmac_final(struct ahash_request *req)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct s390_kmac_sha2_ctx ctx_backup;
+	int rc;
+
+	/*
+	 * First try synchronous. If this fails for any reason
+	 * schedule this request asynchronous via workqueue.
+	 */
+
+	memcpy(&ctx_backup, ctx, sizeof(*ctx));
+
+	rc = phmac_final(tfm, ctx, req->result, false);
+	if (!rc)
+		goto out;
+
+	memcpy(ctx, &ctx_backup, sizeof(*ctx));
+
+	req_ctx->req = req;
+	INIT_DELAYED_WORK(&req_ctx->work, phmac_wq_final_fn);
+	schedule_delayed_work(&req_ctx->work, 0);
+	rc = -EINPROGRESS;
+
+out:
+	pr_debug("rc=%d\n", rc);
+	return rc;
+}
+
+static void phmac_wq_finup_fn(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct s390_phmac_req_ctx *req_ctx =
+		container_of(dwork, struct s390_phmac_req_ctx, work);
+	struct ahash_request *req = req_ctx->req;
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct crypto_hash_walk walk;
+	int nbytes, rc = 0;
+
+	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+	     nbytes = crypto_hash_walk_done(&walk, 0)) {
+		rc = phmac_update(tfm, ctx, walk.data, nbytes, true);
+		if (rc) {
+			crypto_hash_walk_done(&walk, rc);
+			break;
+		}
+	}
+	if (rc)
+		goto out;
+
+	rc = phmac_final(tfm, ctx, req->result, true);
+
+out:
+	pr_debug("req complete with rc=%d\n", rc);
+	crypto_request_complete(&req->base, rc);
+}
+
+static int s390_phmac_finup(struct ahash_request *req)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct s390_kmac_sha2_ctx ctx_backup;
+	struct crypto_hash_walk walk;
+	int nbytes, rc = 0;
+
+	/*
+	 * First try synchronous. If this fails for any reason
+	 * schedule this request asynchronous via workqueue.
+	 */
+
+	memcpy(&ctx_backup, ctx, sizeof(*ctx));
+
+	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+	     nbytes = crypto_hash_walk_done(&walk, 0)) {
+		rc = phmac_update(tfm, ctx, walk.data, nbytes, false);
+		if (rc) {
+			crypto_hash_walk_done(&walk, rc);
+			break;
+		}
+	}
+
+	if (!rc)
+		rc = phmac_final(tfm, ctx, req->result, false);
+	if (!rc)
+		goto out;
+
+	memcpy(ctx, &ctx_backup, sizeof(*ctx));
+
+	req_ctx->req = req;
+	INIT_DELAYED_WORK(&req_ctx->work, phmac_wq_finup_fn);
+	schedule_delayed_work(&req_ctx->work, 0);
+	rc = -EINPROGRESS;
+
+out:
+	pr_debug("rc=%d\n", rc);
+	return rc;
+}
+
+static void phmac_wq_digest_fn(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct s390_phmac_req_ctx *req_ctx =
+		container_of(dwork, struct s390_phmac_req_ctx, work);
+	struct ahash_request *req = req_ctx->req;
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct crypto_hash_walk walk;
+	int nbytes, rc = 0;
+
+	rc = phmac_init(tfm, ctx, true);
+	if (rc)
+		goto out;
+
+	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+	     nbytes = crypto_hash_walk_done(&walk, 0)) {
+		rc = phmac_update(tfm, ctx, walk.data, nbytes, true);
+		if (rc) {
+			crypto_hash_walk_done(&walk, rc);
+			break;
+		}
+	}
+	if (rc)
+		goto out;
+
+	rc = phmac_final(tfm, ctx, req->result, true);
+
+out:
+	pr_debug("req complete with rc=%d\n", rc);
+	crypto_request_complete(&req->base, rc);
+}
+
+static int s390_phmac_digest(struct ahash_request *req)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+	struct crypto_hash_walk walk;
+	int nbytes, rc;
+
+	/*
+	 * First try synchronous. If this fails for any reason
+	 * schedule this request asynchronous via workqueue.
+	 */
+
+	rc = phmac_init(tfm, ctx, false);
+	if (rc)
+		goto via_wq;
+
+	for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
+	     nbytes = crypto_hash_walk_done(&walk, 0)) {
+		rc = phmac_update(tfm, ctx, walk.data, nbytes, false);
+		if (rc) {
+			crypto_hash_walk_done(&walk, rc);
+			break;
+		}
+	}
+	if (rc)
+		goto via_wq;
+
+	rc = phmac_final(tfm, ctx, req->result, false);
+	if (!rc)
+		goto out;
+
+via_wq:
+	req_ctx->req = req;
+	INIT_DELAYED_WORK(&req_ctx->work, phmac_wq_digest_fn);
+	schedule_delayed_work(&req_ctx->work, 0);
+	rc = -EINPROGRESS;
+
+out:
+	pr_debug("rc=%d\n", rc);
+	return rc;
+}
+
+static int s390_phmac_setkey(struct crypto_ahash *tfm,
+			     const u8 *key, unsigned int keylen)
+{
+	struct s390_phmac_ctx *tfm_ctx = crypto_ahash_ctx(tfm);
+
+	if (tfm_ctx->keylen) {
+		kfree_sensitive(tfm_ctx->key);
+		tfm_ctx->key = NULL;
+		tfm_ctx->keylen = 0;
+	}
+
+	tfm_ctx->key = kmemdup(key, keylen, GFP_ATOMIC);
+	if (!tfm_ctx->key)
+		return -ENOMEM;
+	tfm_ctx->keylen = keylen;
+
+	/* Always trigger an asynch key convert */
+	spin_lock_bh(&tfm_ctx->pk_lock);
+	tfm_ctx->pk_state = PK_STATE_CONVERT_IN_PROGRESS;
+	spin_unlock_bh(&tfm_ctx->pk_lock);
+	schedule_delayed_work(&tfm_ctx->work, 0);
+
+	pr_debug("rc=0\n");
+	return 0;
+}
+
+static int s390_phmac_import(struct ahash_request *req, const void *in)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+
+	memcpy(ctx, in, sizeof(*ctx));
+
+	return 0;
+}
+
+static int s390_phmac_export(struct ahash_request *req, void *out)
+{
+	struct s390_phmac_req_ctx *req_ctx = ahash_request_ctx(req);
+	struct s390_kmac_sha2_ctx *ctx = &req_ctx->sha2_ctx;
+
+	memcpy(out, ctx, sizeof(*ctx));
+
+	return 0;
+}
+
+static int s390_phmac_init_tfm(struct crypto_ahash *tfm)
+{
+	struct s390_phmac_ctx *tfm_ctx = crypto_ahash_ctx(tfm);
+
+	tfm_ctx->key = NULL;
+	tfm_ctx->keylen = 0;
+
+	INIT_DELAYED_WORK(&tfm_ctx->work, phmac_wq_convert_key_fn);
+
+	tfm_ctx->pk_state = PK_STATE_NO_KEY;
+	spin_lock_init(&tfm_ctx->pk_lock);
+
+	crypto_ahash_set_reqsize(tfm, sizeof(struct s390_phmac_req_ctx));
+
+	pr_debug("rc=0\n");
+	return 0;
+}
+
+static void s390_phmac_exit_tfm(struct crypto_ahash *tfm)
+{
+	struct s390_phmac_ctx *tfm_ctx = crypto_ahash_ctx(tfm);
+
+	flush_delayed_work(&tfm_ctx->work);
+
+	memzero_explicit(&tfm_ctx->pk, sizeof(tfm_ctx->pk));
+	kfree_sensitive(tfm_ctx->key);
+
+	pr_debug("\n");
+}
+
+#define S390_ASYNC_PHMAC_ALG(x)						\
+{									\
+	.init = s390_phmac_init,					\
+	.update = s390_phmac_update,					\
+	.final = s390_phmac_final,					\
+	.finup = s390_phmac_finup,					\
+	.digest = s390_phmac_digest,					\
+	.setkey = s390_phmac_setkey,					\
+	.import = s390_phmac_import,					\
+	.export = s390_phmac_export,					\
+	.init_tfm = s390_phmac_init_tfm,				\
+	.exit_tfm = s390_phmac_exit_tfm,				\
+	.halg = {							\
+		.digestsize = SHA##x##_DIGEST_SIZE,			\
+		.statesize = sizeof(struct s390_kmac_sha2_ctx),		\
+		.base = {						\
+			.cra_name = "phmac(sha" #x ")",			\
+			.cra_driver_name = "phmac_s390_sha" #x,		\
+			.cra_blocksize = SHA##x##_BLOCK_SIZE,		\
+			.cra_priority = 400,				\
+			.cra_flags = CRYPTO_ALG_ASYNC,			\
+			.cra_ctxsize = sizeof(struct s390_phmac_ctx),	\
+			.cra_module = THIS_MODULE,			\
+		},							\
+	},								\
+}
+
+static struct s390_hmac_alg {
+	unsigned int fc;
+	struct ahash_alg alg;
+	bool registered;
+} s390_hmac_algs[] = {
+	{
+		.fc = CPACF_KMAC_PHMAC_SHA_224,
+		.alg = S390_ASYNC_PHMAC_ALG(224),
+	}, {
+		.fc = CPACF_KMAC_PHMAC_SHA_256,
+		.alg = S390_ASYNC_PHMAC_ALG(256),
+	}, {
+		.fc = CPACF_KMAC_PHMAC_SHA_384,
+		.alg = S390_ASYNC_PHMAC_ALG(384),
+	}, {
+		.fc = CPACF_KMAC_PHMAC_SHA_512,
+		.alg = S390_ASYNC_PHMAC_ALG(512),
+	}
+};
+
+static __always_inline void _s390_hmac_algs_unregister(void)
+{
+	struct s390_hmac_alg *hmac;
+	int i;
+
+	for (i = ARRAY_SIZE(s390_hmac_algs) - 1; i >= 0; i--) {
+		hmac = &s390_hmac_algs[i];
+		if (hmac->registered)
+			crypto_unregister_ahash(&hmac->alg);
+	}
+}
+
+static int __init phmac_s390_init(void)
+{
+	struct s390_hmac_alg *hmac;
+	int i, rc = -ENODEV;
+
+	for (i = 0; i < ARRAY_SIZE(s390_hmac_algs); i++) {
+		hmac = &s390_hmac_algs[i];
+		if (!cpacf_query_func(CPACF_KMAC, hmac->fc))
+			continue;
+		rc = crypto_register_ahash(&hmac->alg);
+		if (rc) {
+			pr_err("unable to register %s\n",
+			       hmac->alg.halg.base.cra_name);
+			goto out;
+		}
+		hmac->registered = true;
+		pr_debug("registered %s\n", hmac->alg.halg.base.cra_name);
+	}
+	return rc;
+out:
+	_s390_hmac_algs_unregister();
+	return rc;
+}
+
+static void __exit phmac_s390_exit(void)
+{
+	_s390_hmac_algs_unregister();
+}
+
+module_init(phmac_s390_init);
+module_exit(phmac_s390_exit);
+
+MODULE_ALIAS_CRYPTO("phmac(sha224)");
+MODULE_ALIAS_CRYPTO("phmac(sha256)");
+MODULE_ALIAS_CRYPTO("phmac(sha384)");
+MODULE_ALIAS_CRYPTO("phmac(sha512)");
+
+MODULE_DESCRIPTION("S390 HMAC driver for protected keys");
+MODULE_LICENSE("GPL");
diff --git a/drivers/crypto/Kconfig b/drivers/crypto/Kconfig
index 0a9cdd31cbd9..519305e04f18 100644
--- a/drivers/crypto/Kconfig
+++ b/drivers/crypto/Kconfig
@@ -187,6 +187,18 @@  config CRYPTO_PAES_S390
 	  Select this option if you want to use the paes cipher
 	  for example to use protected key encrypted devices.
 
+config CRYPTO_PHMAC_S390
+	tristate "PHMAC cipher algorithms"
+	depends on S390
+	depends on PKEY
+	select CRYPTO_HASH
+	help
+	  This is the s390 hardware accelerated implementation of the
+	  protected key HMAC support for SHA224, SHA256, SHA384 and SHA512.
+
+	  Select this option if you want to use the phmac digests
+	  for example to use dm-integrity with secure/protected keys.
+
 config S390_PRNG
 	tristate "Pseudo random number generator device driver"
 	depends on S390