s390/pkey: Introduce pkey kernel module

This patch introcudes a new kernel module pkey which is providing
protected key handling and management functions. The pkey API is
available within the kernel for other s390 specific code to create
and manage protected keys. Additionally the functions are exported
to user space via IOCTL calls. The implementation makes extensive
use of functions provided by the zcrypt device driver. For
generating protected keys from secure keys there is also a CEX
coprocessor card needed.

Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

2 files changed, 1152 insertions, 0 deletions

diff --git a/drivers/s390/crypto/Makefile b/drivers/s390/crypto/Makefile
index 0a7fb83f35e5..be36f1010d75 100644
--- a/drivers/s390/crypto/Makefile
+++ b/drivers/s390/crypto/Makefile
@@ -10,3 +10,7 @@ zcrypt-objs += zcrypt_msgtype6.o zcrypt_msgtype50.o
 obj-$(CONFIG_ZCRYPT) += zcrypt.o
 # adapter drivers depend on ap.o and zcrypt.o
 obj-$(CONFIG_ZCRYPT) += zcrypt_pcixcc.o zcrypt_cex2a.o zcrypt_cex4.o
+
+# pkey kernel module
+pkey-objs := pkey_api.o
+obj-$(CONFIG_PKEY) += pkey.o
diff --git a/drivers/s390/crypto/pkey_api.c b/drivers/s390/crypto/pkey_api.c
new file mode 100644
index 000000000000..40f1136f5568
--- /dev/null
+++ b/drivers/s390/crypto/pkey_api.c
@@ -0,0 +1,1148 @@
+/*
+ *  pkey device driver
+ *
+ *  Copyright IBM Corp. 2017
+ *  Author(s): Harald Freudenberger
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ */
+
+#define KMSG_COMPONENT "pkey"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/kallsyms.h>
+#include <linux/debugfs.h>
+#include <asm/zcrypt.h>
+#include <asm/cpacf.h>
+#include <asm/pkey.h>
+
+#include "zcrypt_api.h"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("IBM Corporation");
+MODULE_DESCRIPTION("s390 protected key interface");
+
+/* Size of parameter block used for all cca requests/replies */
+#define PARMBSIZE 512
+
+/* Size of vardata block used for some of the cca requests/replies */
+#define VARDATASIZE 4096
+
+/*
+ * debug feature data and functions
+ */
+
+static debug_info_t *debug_info;
+
+#define DEBUG_DBG(...)	debug_sprintf_event(debug_info, 6, ##__VA_ARGS__)
+#define DEBUG_INFO(...) debug_sprintf_event(debug_info, 5, ##__VA_ARGS__)
+#define DEBUG_WARN(...) debug_sprintf_event(debug_info, 4, ##__VA_ARGS__)
+#define DEBUG_ERR(...)	debug_sprintf_event(debug_info, 3, ##__VA_ARGS__)
+
+static void __init pkey_debug_init(void)
+{
+	debug_info = debug_register("pkey", 1, 1, 4 * sizeof(long));
+	debug_register_view(debug_info, &debug_sprintf_view);
+	debug_set_level(debug_info, 3);
+}
+
+static void __exit pkey_debug_exit(void)
+{
+	debug_unregister(debug_info);
+}
+
+/* inside view of a secure key token (only type 0x01 version 0x04) */
+struct secaeskeytoken {
+	u8  type;     /* 0x01 for internal key token */
+	u8  res0[3];
+	u8  version;  /* should be 0x04 */
+	u8  res1[1];
+	u8  flag;     /* key flags */
+	u8  res2[1];
+	u64 mkvp;     /* master key verification pattern */
+	u8  key[32];  /* key value (encrypted) */
+	u8  cv[8];    /* control vector */
+	u16 bitsize;  /* key bit size */
+	u16 keysize;  /* key byte size */
+	u8  tvv[4];   /* token validation value */
+} __packed;
+
+/*
+ * Simple check if the token is a valid CCA secure AES key
+ * token. If keybitsize is given, the bitsize of the key is
+ * also checked. Returns 0 on success or errno value on failure.
+ */
+static int check_secaeskeytoken(u8 *token, int keybitsize)
+{
+	struct secaeskeytoken *t = (struct secaeskeytoken *) token;
+
+	if (t->type != 0x01) {
+		DEBUG_ERR(
+			"check_secaeskeytoken secure token check failed, type mismatch 0x%02x != 0x01\n",
+			(int) t->type);
+		return -EINVAL;
+	}
+	if (t->version != 0x04) {
+		DEBUG_ERR(
+			"check_secaeskeytoken secure token check failed, version mismatch 0x%02x != 0x04\n",
+			(int) t->version);
+		return -EINVAL;
+	}
+	if (keybitsize > 0 && t->bitsize != keybitsize) {
+		DEBUG_ERR(
+			"check_secaeskeytoken secure token check failed, bitsize mismatch %d != %d\n",
+			(int) t->bitsize, keybitsize);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+/*
+ * Allocate consecutive memory for request CPRB, request param
+ * block, reply CPRB and reply param block and fill in values
+ * for the common fields. Returns 0 on success or errno value
+ * on failure.
+ */
+static int alloc_and_prep_cprbmem(size_t paramblen,
+				  u8 **pcprbmem,
+				  struct CPRBX **preqCPRB,
+				  struct CPRBX **prepCPRB)
+{
+	u8 *cprbmem;
+	size_t cprbplusparamblen = sizeof(struct CPRBX) + paramblen;
+	struct CPRBX *preqcblk, *prepcblk;
+
+	/*
+	 * allocate consecutive memory for request CPRB, request param
+	 * block, reply CPRB and reply param block
+	 */
+	cprbmem = kmalloc(2 * cprbplusparamblen, GFP_KERNEL);
+	if (!cprbmem)
+		return -ENOMEM;
+	memset(cprbmem, 0, 2 * cprbplusparamblen);
+
+	preqcblk = (struct CPRBX *) cprbmem;
+	prepcblk = (struct CPRBX *) (cprbmem + cprbplusparamblen);
+
+	/* fill request cprb struct */
+	preqcblk->cprb_len = sizeof(struct CPRBX);
+	preqcblk->cprb_ver_id = 0x02;
+	memcpy(preqcblk->func_id, "T2", 2);
+	preqcblk->rpl_msgbl = cprbplusparamblen;
+	if (paramblen) {
+		preqcblk->req_parmb =
+			((u8 *) preqcblk) + sizeof(struct CPRBX);
+		preqcblk->rpl_parmb =
+			((u8 *) prepcblk) + sizeof(struct CPRBX);
+	}
+
+	*pcprbmem = cprbmem;
+	*preqCPRB = preqcblk;
+	*prepCPRB = prepcblk;
+
+	return 0;
+}
+
+/*
+ * Free the cprb memory allocated with the function above.
+ * If the scrub value is not zero, the memory is filled
+ * with zeros before freeing (useful if there was some
+ * clear key material in there).
+ */
+static void free_cprbmem(void *mem, size_t paramblen, int scrub)
+{
+	if (scrub)
+		memzero_explicit(mem, 2 * (sizeof(struct CPRBX) + paramblen));
+	kfree(mem);
+}
+
+/*
+ * Helper function to prepare the xcrb struct
+ */
+static inline void prep_xcrb(struct ica_xcRB *pxcrb,
+			     u16 cardnr,
+			     struct CPRBX *preqcblk,
+			     struct CPRBX *prepcblk)
+{
+	memset(pxcrb, 0, sizeof(*pxcrb));
+	pxcrb->agent_ID = 0x4341; /* 'CA' */
+	pxcrb->user_defined = (cardnr == 0xFFFF ? AUTOSELECT : cardnr);
+	pxcrb->request_control_blk_length =
+		preqcblk->cprb_len + preqcblk->req_parml;
+	pxcrb->request_control_blk_addr = (void *) preqcblk;
+	pxcrb->reply_control_blk_length = preqcblk->rpl_msgbl;
+	pxcrb->reply_control_blk_addr = (void *) prepcblk;
+}
+
+/*
+ * Helper function which calls zcrypt_send_cprb with
+ * memory management segment adjusted to kernel space
+ * so that the copy_from_user called within this
+ * function do in fact copy from kernel space.
+ */
+static inline int _zcrypt_send_cprb(struct ica_xcRB *xcrb)
+{
+	int rc;
+	mm_segment_t old_fs = get_fs();
+
+	set_fs(KERNEL_DS);
+	rc = zcrypt_send_cprb(xcrb);
+	set_fs(old_fs);
+
+	return rc;
+}
+
+/*
+ * Generate (random) AES secure key.
+ */
+int pkey_genseckey(u16 cardnr, u16 domain,
+		   u32 keytype, struct pkey_seckey *seckey)
+{
+	int i, rc, keysize;
+	int seckeysize;
+	u8 *mem;
+	struct CPRBX *preqcblk, *prepcblk;
+	struct ica_xcRB xcrb;
+	struct kgreqparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		struct lv1 {
+			u16 len;
+			char  key_form[8];
+			char  key_length[8];
+			char  key_type1[8];
+			char  key_type2[8];
+		} lv1;
+		struct lv2 {
+			u16 len;
+			struct keyid {
+				u16 len;
+				u16 attr;
+				u8  data[SECKEYBLOBSIZE];
+			} keyid[6];
+		} lv2;
+	} *preqparm;
+	struct kgrepparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		struct lv3 {
+			u16 len;
+			u16 keyblocklen;
+			struct {
+				u16 toklen;
+				u16 tokattr;
+				u8  tok[0];
+				/* ... some more data ... */
+			} keyblock;
+		} lv3;
+	} *prepparm;
+
+	/* get already prepared memory for 2 cprbs with param block each */
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	if (rc)
+		return rc;
+
+	/* fill request cprb struct */
+	preqcblk->domain = domain;
+
+	/* fill request cprb param block with KG request */
+	preqparm = (struct kgreqparm *) preqcblk->req_parmb;
+	memcpy(preqparm->subfunc_code, "KG", 2);
+	preqparm->rule_array_len = sizeof(preqparm->rule_array_len);
+	preqparm->lv1.len = sizeof(struct lv1);
+	memcpy(preqparm->lv1.key_form,	 "OP      ", 8);
+	switch (keytype) {
+	case PKEY_KEYTYPE_AES_128:
+		keysize = 16;
+		memcpy(preqparm->lv1.key_length, "KEYLN16 ", 8);
+		break;
+	case PKEY_KEYTYPE_AES_192:
+		keysize = 24;
+		memcpy(preqparm->lv1.key_length, "KEYLN24 ", 8);
+		break;
+	case PKEY_KEYTYPE_AES_256:
+		keysize = 32;
+		memcpy(preqparm->lv1.key_length, "KEYLN32 ", 8);
+		break;
+	default:
+		DEBUG_ERR(
+			"pkey_genseckey unknown/unsupported keytype %d\n",
+			keytype);
+		rc = -EINVAL;
+		goto out;
+	}
+	memcpy(preqparm->lv1.key_type1,  "AESDATA ", 8);
+	preqparm->lv2.len = sizeof(struct lv2);
+	for (i = 0; i < 6; i++) {
+		preqparm->lv2.keyid[i].len = sizeof(struct keyid);
+		preqparm->lv2.keyid[i].attr = (i == 2 ? 0x30 : 0x10);
+	}
+	preqcblk->req_parml = sizeof(struct kgreqparm);
+
+	/* fill xcrb struct */
+	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
+
+	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
+	rc = _zcrypt_send_cprb(&xcrb);
+	if (rc) {
+		DEBUG_ERR(
+			"pkey_genseckey zcrypt_send_cprb (cardnr=%d domain=%d) failed with errno %d\n",
+			(int) cardnr, (int) domain, rc);
+		goto out;
+	}
+
+	/* check response returncode and reasoncode */
+	if (prepcblk->ccp_rtcode != 0) {
+		DEBUG_ERR(
+			"pkey_genseckey secure key generate failure, card response %d/%d\n",
+			(int) prepcblk->ccp_rtcode,
+			(int) prepcblk->ccp_rscode);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* process response cprb param block */
+	prepcblk->rpl_parmb = ((u8 *) prepcblk) + sizeof(struct CPRBX);
+	prepparm = (struct kgrepparm *) prepcblk->rpl_parmb;
+
+	/* check length of the returned secure key token */
+	seckeysize = prepparm->lv3.keyblock.toklen
+		- sizeof(prepparm->lv3.keyblock.toklen)
+		- sizeof(prepparm->lv3.keyblock.tokattr);
+	if (seckeysize != SECKEYBLOBSIZE) {
+		DEBUG_ERR(
+			"pkey_genseckey secure token size mismatch %d != %d bytes\n",
+			seckeysize, SECKEYBLOBSIZE);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* check secure key token */
+	rc = check_secaeskeytoken(prepparm->lv3.keyblock.tok, 8*keysize);
+	if (rc) {
+		rc = -EIO;
+		goto out;
+	}
+
+	/* copy the generated secure key token */
+	memcpy(seckey->seckey, prepparm->lv3.keyblock.tok, SECKEYBLOBSIZE);
+
+out:
+	free_cprbmem(mem, PARMBSIZE, 0);
+	return rc;
+}
+EXPORT_SYMBOL(pkey_genseckey);
+
+/*
+ * Generate an AES secure key with given key value.
+ */
+int pkey_clr2seckey(u16 cardnr, u16 domain, u32 keytype,
+		    const struct pkey_clrkey *clrkey,
+		    struct pkey_seckey *seckey)
+{
+	int rc, keysize, seckeysize;
+	u8 *mem;
+	struct CPRBX *preqcblk, *prepcblk;
+	struct ica_xcRB xcrb;
+	struct cmreqparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		char  rule_array[8];
+		struct lv1 {
+			u16 len;
+			u8  clrkey[0];
+		} lv1;
+		struct lv2 {
+			u16 len;
+			struct keyid {
+				u16 len;
+				u16 attr;
+				u8  data[SECKEYBLOBSIZE];
+			} keyid;
+		} lv2;
+	} *preqparm;
+	struct lv2 *plv2;
+	struct cmrepparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		struct lv3 {
+			u16 len;
+			u16 keyblocklen;
+			struct {
+				u16 toklen;
+				u16 tokattr;
+				u8  tok[0];
+				/* ... some more data ... */
+			} keyblock;
+		} lv3;
+	} *prepparm;
+
+	/* get already prepared memory for 2 cprbs with param block each */
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	if (rc)
+		return rc;
+
+	/* fill request cprb struct */
+	preqcblk->domain = domain;
+
+	/* fill request cprb param block with CM request */
+	preqparm = (struct cmreqparm *) preqcblk->req_parmb;
+	memcpy(preqparm->subfunc_code, "CM", 2);
+	memcpy(preqparm->rule_array, "AES     ", 8);
+	preqparm->rule_array_len =
+		sizeof(preqparm->rule_array_len) + sizeof(preqparm->rule_array);
+	switch (keytype) {
+	case PKEY_KEYTYPE_AES_128:
+		keysize = 16;
+		break;
+	case PKEY_KEYTYPE_AES_192:
+		keysize = 24;
+		break;
+	case PKEY_KEYTYPE_AES_256:
+		keysize = 32;
+		break;
+	default:
+		DEBUG_ERR(
+			"pkey_clr2seckey unknown/unsupported keytype %d\n",
+			keytype);
+		rc = -EINVAL;
+		goto out;
+	}
+	preqparm->lv1.len = sizeof(struct lv1) + keysize;
+	memcpy(preqparm->lv1.clrkey, clrkey->clrkey, keysize);
+	plv2 = (struct lv2 *) (((u8 *) &preqparm->lv2) + keysize);
+	plv2->len = sizeof(struct lv2);
+	plv2->keyid.len = sizeof(struct keyid);
+	plv2->keyid.attr = 0x30;
+	preqcblk->req_parml = sizeof(struct cmreqparm) + keysize;
+
+	/* fill xcrb struct */
+	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
+
+	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
+	rc = _zcrypt_send_cprb(&xcrb);
+	if (rc) {
+		DEBUG_ERR(
+			"pkey_clr2seckey zcrypt_send_cprb (cardnr=%d domain=%d) failed with errno %d\n",
+			(int) cardnr, (int) domain, rc);
+		goto out;
+	}
+
+	/* check response returncode and reasoncode */
+	if (prepcblk->ccp_rtcode != 0) {
+		DEBUG_ERR(
+			"pkey_clr2seckey clear key import failure, card response %d/%d\n",
+			(int) prepcblk->ccp_rtcode,
+			(int) prepcblk->ccp_rscode);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* process response cprb param block */
+	prepcblk->rpl_parmb = ((u8 *) prepcblk) + sizeof(struct CPRBX);
+	prepparm = (struct cmrepparm *) prepcblk->rpl_parmb;
+
+	/* check length of the returned secure key token */
+	seckeysize = prepparm->lv3.keyblock.toklen
+		- sizeof(prepparm->lv3.keyblock.toklen)
+		- sizeof(prepparm->lv3.keyblock.tokattr);
+	if (seckeysize != SECKEYBLOBSIZE) {
+		DEBUG_ERR(
+			"pkey_clr2seckey secure token size mismatch %d != %d bytes\n",
+			seckeysize, SECKEYBLOBSIZE);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* check secure key token */
+	rc = check_secaeskeytoken(prepparm->lv3.keyblock.tok, 8*keysize);
+	if (rc) {
+		rc = -EIO;
+		goto out;
+	}
+
+	/* copy the generated secure key token */
+	memcpy(seckey->seckey, prepparm->lv3.keyblock.tok, SECKEYBLOBSIZE);
+
+out:
+	free_cprbmem(mem, PARMBSIZE, 1);
+	return rc;
+}
+EXPORT_SYMBOL(pkey_clr2seckey);
+
+/*
+ * Derive a proteced key from the secure key blob.
+ */
+int pkey_sec2protkey(u16 cardnr, u16 domain,
+		     const struct pkey_seckey *seckey,
+		     struct pkey_protkey *protkey)
+{
+	int rc;
+	u8 *mem;
+	struct CPRBX *preqcblk, *prepcblk;
+	struct ica_xcRB xcrb;
+	struct uskreqparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		struct lv1 {
+			u16 len;
+			u16 attr_len;
+			u16 attr_flags;
+		} lv1;
+		struct lv2 {
+			u16 len;
+			u16 attr_len;
+			u16 attr_flags;
+			u8  token[0];	      /* cca secure key token */
+		} lv2 __packed;
+	} *preqparm;
+	struct uskrepparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		struct lv3 {
+			u16 len;
+			u16 attr_len;
+			u16 attr_flags;
+			struct cpacfkeyblock {
+				u8  version;  /* version of this struct */
+				u8  flags[2];
+				u8  algo;
+				u8  form;
+				u8  pad1[3];
+				u16 keylen;
+				u8  key[64];  /* the key (keylen bytes) */
+				u16 keyattrlen;
+				u8  keyattr[32];
+				u8  pad2[1];
+				u8  vptype;
+				u8  vp[32];  /* verification pattern */
+			} keyblock;
+		} lv3 __packed;
+	} *prepparm;
+
+	/* get already prepared memory for 2 cprbs with param block each */
+	rc = alloc_and_prep_cprbmem(PARMBSIZE, &mem, &preqcblk, &prepcblk);
+	if (rc)
+		return rc;
+
+	/* fill request cprb struct */
+	preqcblk->domain = domain;
+
+	/* fill request cprb param block with USK request */
+	preqparm = (struct uskreqparm *) preqcblk->req_parmb;
+	memcpy(preqparm->subfunc_code, "US", 2);
+	preqparm->rule_array_len = sizeof(preqparm->rule_array_len);
+	preqparm->lv1.len = sizeof(struct lv1);
+	preqparm->lv1.attr_len = sizeof(struct lv1) - sizeof(preqparm->lv1.len);
+	preqparm->lv1.attr_flags = 0x0001;
+	preqparm->lv2.len = sizeof(struct lv2) + SECKEYBLOBSIZE;
+	preqparm->lv2.attr_len = sizeof(struct lv2)
+		- sizeof(preqparm->lv2.len) + SECKEYBLOBSIZE;
+	preqparm->lv2.attr_flags = 0x0000;
+	memcpy(preqparm->lv2.token, seckey->seckey, SECKEYBLOBSIZE);
+	preqcblk->req_parml = sizeof(struct uskreqparm) + SECKEYBLOBSIZE;
+
+	/* fill xcrb struct */
+	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
+
+	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
+	rc = _zcrypt_send_cprb(&xcrb);
+	if (rc) {
+		DEBUG_ERR(
+			"pkey_sec2protkey zcrypt_send_cprb (cardnr=%d domain=%d) failed with errno %d\n",
+			(int) cardnr, (int) domain, rc);
+		goto out;
+	}
+
+	/* check response returncode and reasoncode */
+	if (prepcblk->ccp_rtcode != 0) {
+		DEBUG_ERR(
+			"pkey_sec2protkey unwrap secure key failure, card response %d/%d\n",
+			(int) prepcblk->ccp_rtcode,
+			(int) prepcblk->ccp_rscode);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* process response cprb param block */
+	prepcblk->rpl_parmb = ((u8 *) prepcblk) + sizeof(struct CPRBX);
+	prepparm = (struct uskrepparm *) prepcblk->rpl_parmb;
+
+	/* check the returned keyblock */
+	if (prepparm->lv3.keyblock.version != 0x01) {
+		DEBUG_ERR(
+			"pkey_sec2protkey reply param keyblock version mismatch 0x%02x != 0x01\n",
+			(int) prepparm->lv3.keyblock.version);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* copy the tanslated protected key */
+	switch (prepparm->lv3.keyblock.keylen) {
+	case 16+32:
+		protkey->type = PKEY_KEYTYPE_AES_128;
+		break;
+	case 24+32:
+		protkey->type = PKEY_KEYTYPE_AES_192;
+		break;
+	case 32+32:
+		protkey->type = PKEY_KEYTYPE_AES_256;
+		break;
+	default:
+		DEBUG_ERR("pkey_sec2protkey unknown/unsupported keytype %d\n",
+			  prepparm->lv3.keyblock.keylen);
+		rc = -EIO;
+		goto out;
+	}
+	protkey->len = prepparm->lv3.keyblock.keylen;
+	memcpy(protkey->protkey, prepparm->lv3.keyblock.key, protkey->len);
+
+out:
+	free_cprbmem(mem, PARMBSIZE, 0);
+	return rc;
+}
+EXPORT_SYMBOL(pkey_sec2protkey);
+
+/*
+ * Create a protected key from a clear key value.
+ */
+int pkey_clr2protkey(u32 keytype,
+		     const struct pkey_clrkey *clrkey,
+		     struct pkey_protkey *protkey)
+{
+	long fc;
+	int keysize;
+	u8 paramblock[64];
+
+	switch (keytype) {
+	case PKEY_KEYTYPE_AES_128:
+		keysize = 16;
+		fc = CPACF_PCKMO_ENC_AES_128_KEY;
+		break;
+	case PKEY_KEYTYPE_AES_192:
+		keysize = 24;
+		fc = CPACF_PCKMO_ENC_AES_192_KEY;
+		break;
+	case PKEY_KEYTYPE_AES_256:
+		keysize = 32;
+		fc = CPACF_PCKMO_ENC_AES_256_KEY;
+		break;
+	default:
+		DEBUG_ERR("pkey_clr2protkey unknown/unsupported keytype %d\n",
+			  keytype);
+		return -EINVAL;
+	}
+
+	/* prepare param block */
+	memset(paramblock, 0, sizeof(paramblock));
+	memcpy(paramblock, clrkey->clrkey, keysize);
+
+	/* call the pckmo instruction */
+	cpacf_pckmo(fc, paramblock);
+
+	/* copy created protected key */
+	protkey->type = keytype;
+	protkey->len = keysize + 32;
+	memcpy(protkey->protkey, paramblock, keysize + 32);
+
+	return 0;
+}
+EXPORT_SYMBOL(pkey_clr2protkey);
+
+/*
+ * query cryptographic facility from adapter
+ */
+static int query_crypto_facility(u16 cardnr, u16 domain,
+				 const char *keyword,
+				 u8 *rarray, size_t *rarraylen,
+				 u8 *varray, size_t *varraylen)
+{
+	int rc;
+	u16 len;
+	u8 *mem, *ptr;
+	struct CPRBX *preqcblk, *prepcblk;
+	struct ica_xcRB xcrb;
+	struct fqreqparm {
+		u8  subfunc_code[2];
+		u16 rule_array_len;
+		char  rule_array[8];
+		struct lv1 {
+			u16 len;
+			u8  data[VARDATASIZE];
+		} lv1;
+		u16 dummylen;
+	} *preqparm;
+	size_t parmbsize = sizeof(struct fqreqparm);
+	struct fqrepparm {
+		u8  subfunc_code[2];
+		u8  lvdata[0];
+	} *prepparm;
+
+	/* get already prepared memory for 2 cprbs with param block each */
+	rc = alloc_and_prep_cprbmem(parmbsize, &mem, &preqcblk, &prepcblk);
+	if (rc)
+		return rc;
+
+	/* fill request cprb struct */
+	preqcblk->domain = domain;
+
+	/* fill request cprb param block with FQ request */
+	preqparm = (struct fqreqparm *) preqcblk->req_parmb;
+	memcpy(preqparm->subfunc_code, "FQ", 2);
+	strncpy(preqparm->rule_array, keyword, sizeof(preqparm->rule_array));
+	preqparm->rule_array_len =
+		sizeof(preqparm->rule_array_len) + sizeof(preqparm->rule_array);
+	preqparm->lv1.len = sizeof(preqparm->lv1);
+	preqparm->dummylen = sizeof(preqparm->dummylen);
+	preqcblk->req_parml = parmbsize;
+
+	/* fill xcrb struct */
+	prep_xcrb(&xcrb, cardnr, preqcblk, prepcblk);
+
+	/* forward xcrb with request CPRB and reply CPRB to zcrypt dd */
+	rc = _zcrypt_send_cprb(&xcrb);
+	if (rc) {
+		DEBUG_ERR(
+			"query_crypto_facility zcrypt_send_cprb (cardnr=%d domain=%d) failed with errno %d\n",
+			(int) cardnr, (int) domain, rc);
+		goto out;
+	}
+
+	/* check response returncode and reasoncode */
+	if (prepcblk->ccp_rtcode != 0) {
+		DEBUG_ERR(
+			"query_crypto_facility unwrap secure key failure, card response %d/%d\n",
+			(int) prepcblk->ccp_rtcode,
+			(int) prepcblk->ccp_rscode);
+		rc = -EIO;
+		goto out;
+	}
+
+	/* process response cprb param block */
+	prepcblk->rpl_parmb = ((u8 *) prepcblk) + sizeof(struct CPRBX);
+	prepparm = (struct fqrepparm *) prepcblk->rpl_parmb;
+	ptr = prepparm->lvdata;
+
+	/* check and possibly copy reply rule array */
+	len = *((u16 *) ptr);
+	if (len > sizeof(u16)) {
+		ptr += sizeof(u16);
+		len -= sizeof(u16);
+		if (rarray && rarraylen && *rarraylen > 0) {
+			*rarraylen = (len > *rarraylen ? *rarraylen : len);
+			memcpy(rarray, ptr, *rarraylen);
+		}
+		ptr += len;
+	}
+	/* check and possible copy reply var array */
+	len = *((u16 *) ptr);
+	if (len > sizeof(u16)) {
+		ptr += sizeof(u16);
+		len -= sizeof(u16);
+		if (varray && varraylen && *varraylen > 0) {
+			*varraylen = (len > *varraylen ? *varraylen : len);
+			memcpy(varray, ptr, *varraylen);
+		}
+		ptr += len;
+	}
+
+out:
+	free_cprbmem(mem, parmbsize, 0);
+	return rc;
+}
+
+/*
+ * Fetch just the mkvp value via query_crypto_facility from adapter.
+ */
+static int fetch_mkvp(u16 cardnr, u16 domain, u64 *mkvp)
+{
+	int rc, found = 0;
+	size_t rlen, vlen;
+	u8 *rarray, *varray, *pg;
+
+	pg = (u8 *) __get_free_page(GFP_KERNEL);
+	if (!pg)
+		return -ENOMEM;
+	rarray = pg;
+	varray = pg + PAGE_SIZE/2;
+	rlen = vlen = PAGE_SIZE/2;
+
+	rc = query_crypto_facility(cardnr, domain, "STATICSA",
+				   rarray, &rlen, varray, &vlen);
+	if (rc == 0 && rlen > 8*8 && vlen > 184+8) {
+		if (rarray[64] == '2') {
+			/* current master key state is valid */
+			*mkvp = *((u64 *)(varray + 184));
+			found = 1;
+		}
+	}
+
+	free_page((unsigned long) pg);
+
+	return found ? 0 : -ENOENT;
+}
+
+/* struct to hold cached mkvp info for each card/domain */
+struct mkvp_info {
+	struct list_head list;
+	u16 cardnr;
+	u16 domain;
+	u64 mkvp;
+};
+
+/* a list with mkvp_info entries */
+static LIST_HEAD(mkvp_list);
+static DEFINE_SPINLOCK(mkvp_list_lock);
+
+static int mkvp_cache_fetch(u16 cardnr, u16 domain, u64 *mkvp)
+{
+	int rc = -ENOENT;
+	struct mkvp_info *ptr;
+
+	spin_lock_bh(&mkvp_list_lock);
+	list_for_each_entry(ptr, &mkvp_list, list) {
+		if (ptr->cardnr == cardnr &&
+		    ptr->domain == domain) {
+			*mkvp = ptr->mkvp;
+			rc = 0;
+			break;
+		}
+	}
+	spin_unlock_bh(&mkvp_list_lock);
+
+	return rc;
+}
+
+static void mkvp_cache_update(u16 cardnr, u16 domain, u64 mkvp)
+{
+	int found = 0;
+	struct mkvp_info *ptr;
+
+	spin_lock_bh(&mkvp_list_lock);
+	list_for_each_entry(ptr, &mkvp_list, list) {
+		if (ptr->cardnr == cardnr &&
+		    ptr->domain == domain) {
+			ptr->mkvp = mkvp;
+			found = 1;
+			break;
+		}
+	}
+	if (!found) {
+		ptr = kmalloc(sizeof(*ptr), GFP_ATOMIC);
+		if (!ptr) {
+			spin_unlock_bh(&mkvp_list_lock);
+			return;
+		}
+		ptr->cardnr = cardnr;
+		ptr->domain = domain;
+		ptr->mkvp = mkvp;
+		list_add(&ptr->list, &mkvp_list);
+	}
+	spin_unlock_bh(&mkvp_list_lock);
+}
+
+static void mkvp_cache_scrub(u16 cardnr, u16 domain)
+{
+	struct mkvp_info *ptr;
+
+	spin_lock_bh(&mkvp_list_lock);
+	list_for_each_entry(ptr, &mkvp_list, list) {
+		if (ptr->cardnr == cardnr &&
+		    ptr->domain == domain) {
+			list_del(&ptr->list);
+			kfree(ptr);
+			break;
+		}
+	}
+	spin_unlock_bh(&mkvp_list_lock);
+}
+
+static void __exit mkvp_cache_free(void)
+{
+	struct mkvp_info *ptr, *pnext;
+
+	spin_lock_bh(&mkvp_list_lock);
+	list_for_each_entry_safe(ptr, pnext, &mkvp_list, list) {
+		list_del(&ptr->list);
+		kfree(ptr);
+	}
+	spin_unlock_bh(&mkvp_list_lock);
+}
+
+/*
+ * Search for a matching crypto card based on the Master Key
+ * Verification Pattern provided inside a secure key.
+ */
+int pkey_findcard(const struct pkey_seckey *seckey,
+		  u16 *pcardnr, u16 *pdomain, int verify)
+{
+	struct secaeskeytoken *t = (struct secaeskeytoken *) seckey;
+	struct zcrypt_device_matrix *device_matrix;
+	u16 card, dom;
+	u64 mkvp;
+	int i, rc;
+
+	/* mkvp must not be zero */
+	if (t->mkvp == 0)
+		return -EINVAL;
+
+	/* fetch status of all crypto cards */
+	device_matrix = kmalloc(sizeof(struct zcrypt_device_matrix),
+				GFP_KERNEL);
+	if (!device_matrix)
+		return -ENOMEM;
+	zcrypt_device_status_mask(device_matrix);
+
+	/* walk through all crypto cards */
+	for (i = 0; i < MAX_ZDEV_ENTRIES; i++) {
+		card = AP_QID_CARD(device_matrix->device[i].qid);
+		dom = AP_QID_QUEUE(device_matrix->device[i].qid);
+		if (device_matrix->device[i].online &&
+		    device_matrix->device[i].functions & 0x04) {
+			/* an enabled CCA Coprocessor card */
+			/* try cached mkvp */
+			if (mkvp_cache_fetch(card, dom, &mkvp) == 0 &&
+			    t->mkvp == mkvp) {
+				if (!verify)
+					break;
+				/* verify: fetch mkvp from adapter */
+				if (fetch_mkvp(card, dom, &mkvp) == 0) {
+					mkvp_cache_update(card, dom, mkvp);
+					if (t->mkvp == mkvp)
+						break;
+				}
+			}
+		} else {
+			/* Card is offline and/or not a CCA card. */
+			/* del mkvp entry from cache if it exists */
+			mkvp_cache_scrub(card, dom);
+		}
+	}
+	if (i >= MAX_ZDEV_ENTRIES) {
+		/* nothing found, so this time without cache */
+		for (i = 0; i < MAX_ZDEV_ENTRIES; i++) {
+			if (!(device_matrix->device[i].online &&
+			      device_matrix->device[i].functions & 0x04))
+				continue;
+			card = AP_QID_CARD(device_matrix->device[i].qid);
+			dom = AP_QID_QUEUE(device_matrix->device[i].qid);
+			/* fresh fetch mkvp from adapter */
+			if (fetch_mkvp(card, dom, &mkvp) == 0) {
+				mkvp_cache_update(card, dom, mkvp);
+				if (t->mkvp == mkvp)
+					break;
+			}
+		}
+	}
+	if (i < MAX_ZDEV_ENTRIES) {
+		if (pcardnr)
+			*pcardnr = card;
+		if (pdomain)
+			*pdomain = dom;
+		rc = 0;
+	} else
+		rc = -ENODEV;
+
+	kfree(device_matrix);
+	return rc;
+}
+EXPORT_SYMBOL(pkey_findcard);
+
+/*
+ * Find card and transform secure key into protected key.
+ */
+int pkey_skey2pkey(const struct pkey_seckey *seckey,
+		   struct pkey_protkey *protkey)
+{
+	u16 cardnr, domain;
+	int rc, verify;
+
+	/*
+	 * The pkey_sec2protkey call may fail when a card has been
+	 * addressed where the master key was changed after last fetch
+	 * of the mkvp into the cache. So first try without verify then
+	 * with verify enabled (thus refreshing the mkvp for each card).
+	 */
+	for (verify = 0; verify < 2; verify++) {
+		rc = pkey_findcard(seckey, &cardnr, &domain, verify);
+		if (rc)
+			continue;
+		rc = pkey_sec2protkey(cardnr, domain, seckey, protkey);
+		if (rc == 0)
+			break;
+	}
+
+	if (rc)
+		DEBUG_DBG("pkey_skey2pkey failed rc=%d\n", rc);
+
+	return rc;
+}
+EXPORT_SYMBOL(pkey_skey2pkey);
+
+/*
+ * File io functions
+ */
+
+static long pkey_unlocked_ioctl(struct file *filp, unsigned int cmd,
+				unsigned long arg)
+{
+	int rc;
+
+	switch (cmd) {
+	case PKEY_GENSECK: {
+		struct pkey_genseck __user *ugs = (void __user *) arg;
+		struct pkey_genseck kgs;
+
+		if (copy_from_user(&kgs, ugs, sizeof(kgs)))
+			return -EFAULT;
+		rc = pkey_genseckey(kgs.cardnr, kgs.domain,
+				    kgs.keytype, &kgs.seckey);
+		DEBUG_DBG("pkey_ioctl pkey_genseckey()=%d\n", rc);
+		if (rc)
+			break;
+		if (copy_to_user(ugs, &kgs, sizeof(kgs)))
+			return -EFAULT;
+		break;
+	}
+	case PKEY_CLR2SECK: {
+		struct pkey_clr2seck __user *ucs = (void __user *) arg;
+		struct pkey_clr2seck kcs;
+
+		if (copy_from_user(&kcs, ucs, sizeof(kcs)))
+			return -EFAULT;
+		rc = pkey_clr2seckey(kcs.cardnr, kcs.domain, kcs.keytype,
+				     &kcs.clrkey, &kcs.seckey);
+		DEBUG_DBG("pkey_ioctl pkey_clr2seckey()=%d\n", rc);
+		if (rc)
+			break;
+		if (copy_to_user(ucs, &kcs, sizeof(kcs)))
+			return -EFAULT;
+		memzero_explicit(&kcs, sizeof(kcs));
+		break;
+	}
+	case PKEY_SEC2PROTK: {
+		struct pkey_sec2protk __user *usp = (void __user *) arg;
+		struct pkey_sec2protk ksp;
+
+		if (copy_from_user(&ksp, usp, sizeof(ksp)))
+			return -EFAULT;
+		rc = pkey_sec2protkey(ksp.cardnr, ksp.domain,
+				      &ksp.seckey, &ksp.protkey);
+		DEBUG_DBG("pkey_ioctl pkey_sec2protkey()=%d\n", rc);
+		if (rc)
+			break;
+		if (copy_to_user(usp, &ksp, sizeof(ksp)))
+			return -EFAULT;
+		break;
+	}
+	case PKEY_CLR2PROTK: {
+		struct pkey_clr2protk __user *ucp = (void __user *) arg;
+		struct pkey_clr2protk kcp;
+
+		if (copy_from_user(&kcp, ucp, sizeof(kcp)))
+			return -EFAULT;
+		rc = pkey_clr2protkey(kcp.keytype,
+				      &kcp.clrkey, &kcp.protkey);
+		DEBUG_DBG("pkey_ioctl pkey_clr2protkey()=%d\n", rc);
+		if (rc)
+			break;
+		if (copy_to_user(ucp, &kcp, sizeof(kcp)))
+			return -EFAULT;
+		memzero_explicit(&kcp, sizeof(kcp));
+		break;
+	}
+	case PKEY_FINDCARD: {
+		struct pkey_findcard __user *ufc = (void __user *) arg;
+		struct pkey_findcard kfc;
+
+		if (copy_from_user(&kfc, ufc, sizeof(kfc)))
+			return -EFAULT;
+		rc = pkey_findcard(&kfc.seckey,
+				   &kfc.cardnr, &kfc.domain, 1);
+		DEBUG_DBG("pkey_ioctl pkey_findcard()=%d\n", rc);
+		if (rc)
+			break;
+		if (copy_to_user(ufc, &kfc, sizeof(kfc)))
+			return -EFAULT;
+		break;
+	}
+	case PKEY_SKEY2PKEY: {
+		struct pkey_skey2pkey __user *usp = (void __user *) arg;
+		struct pkey_skey2pkey ksp;
+
+		if (copy_from_user(&ksp, usp, sizeof(ksp)))
+			return -EFAULT;
+		rc = pkey_skey2pkey(&ksp.seckey, &ksp.protkey);
+		DEBUG_DBG("pkey_ioctl pkey_skey2pkey()=%d\n", rc);
+		if (rc)
+			break;
+		if (copy_to_user(usp, &ksp, sizeof(ksp)))
+			return -EFAULT;
+		break;
+	}
+	default:
+		/* unknown/unsupported ioctl cmd */
+		return -ENOTTY;
+	}
+
+	return rc;
+}
+
+/*
+ * Sysfs and file io operations
+ */
+static const struct file_operations pkey_fops = {
+	.owner		= THIS_MODULE,
+	.open		= nonseekable_open,
+	.llseek		= no_llseek,
+	.unlocked_ioctl = pkey_unlocked_ioctl,
+};
+
+static struct miscdevice pkey_dev = {
+	.name	= "pkey",
+	.minor	= MISC_DYNAMIC_MINOR,
+	.mode	= 0666,
+	.fops	= &pkey_fops,
+};
+
+/*
+ * Module init
+ */
+int __init pkey_init(void)
+{
+	cpacf_mask_t pckmo_functions;
+
+	/* check for pckmo instructions available */
+	if (!cpacf_query(CPACF_PCKMO, &pckmo_functions))
+		return -EOPNOTSUPP;
+	if (!cpacf_test_func(&pckmo_functions, CPACF_PCKMO_ENC_AES_128_KEY) ||
+	    !cpacf_test_func(&pckmo_functions, CPACF_PCKMO_ENC_AES_192_KEY) ||
+	    !cpacf_test_func(&pckmo_functions, CPACF_PCKMO_ENC_AES_256_KEY))
+		return -EOPNOTSUPP;
+
+	pkey_debug_init();
+
+	return misc_register(&pkey_dev);
+}
+
+/*
+ * Module exit
+ */
+static void __exit pkey_exit(void)
+{
+	misc_deregister(&pkey_dev);
+	mkvp_cache_free();
+	pkey_debug_exit();
+}
+
+module_init(pkey_init);
+module_exit(pkey_exit);