// SPDX-License-Identifier: GPL-2.0
/*
 *  pkey device driver
 *
 *  Copyright IBM Corp. 2017
 *  Author(s): Harald Freudenberger
 */

#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(const 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 = kzalloc(2 * cprbplusparamblen, GFP_KERNEL);
        if (!cprbmem)
                return -ENOMEM;

        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 __user *) preqcblk;
        pxcrb->reply_control_blk_length = preqcblk->rpl_msgbl;
        pxcrb->reply_control_blk_addr = (void __user *) 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;
        }
        if (prepcblk->ccp_rscode != 0) {
                DEBUG_WARN(
                        "pkey_sec2protkey unwrap secure key warning, card response %d/%d\n",
                        (int) prepcblk->ccp_rtcode,
                        (int) prepcblk->ccp_rscode);
        }

        /* 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 the current and old mkvp values via
 * query_crypto_facility from adapter.
 */
static int fetch_mkvp(u16 cardnr, u16 domain, u64 mkvp[2])
{
        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[8*8] == '2') {
                        /* current master key state is valid */
                        mkvp[0] = *((u64 *)(varray + 184));
                        mkvp[1] = *((u64 *)(varray + 172));
                        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[2];
};

/* 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[2])
{
        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) {
                        memcpy(mkvp, ptr->mkvp, 2 * sizeof(u64));
                        rc = 0;
                        break;
                }
        }
        spin_unlock_bh(&mkvp_list_lock);

        return rc;
}

static void mkvp_cache_update(u16 cardnr, u16 domain, u64 mkvp[2])
{
        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) {
                        memcpy(ptr->mkvp, mkvp, 2 * sizeof(u64));
                        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;
                memcpy(ptr->mkvp, mkvp, 2 * sizeof(u64));
                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_status_ext *device_status;
        u16 card, dom;
        u64 mkvp[2];
        int i, rc, oi = -1;

        /* mkvp must not be zero */
        if (t->mkvp == 0)
                return -EINVAL;

        /* fetch status of all crypto cards */
        device_status = kmalloc(MAX_ZDEV_ENTRIES_EXT
                                * sizeof(struct zcrypt_device_status_ext),
                                GFP_KERNEL);
        if (!device_status)
                return -ENOMEM;
        zcrypt_device_status_mask_ext(device_status);

        /* walk through all crypto cards */
        for (i = 0; i < MAX_ZDEV_ENTRIES_EXT; i++) {
                card = AP_QID_CARD(device_status[i].qid);
                dom = AP_QID_QUEUE(device_status[i].qid);
                if (device_status[i].online &&
                    device_status[i].functions & 0x04) {
                        /* an enabled CCA Coprocessor card */
                        /* try cached mkvp */
                        if (mkvp_cache_fetch(card, dom, mkvp) == 0 &&
                            t->mkvp == mkvp[0]) {
                                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[0])
                                                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_EXT) {
                /* nothing found, so this time without cache */
                for (i = 0; i < MAX_ZDEV_ENTRIES_EXT; i++) {
                        if (!(device_status[i].online &&
                              device_status[i].functions & 0x04))
                                continue;
                        card = AP_QID_CARD(device_status[i].qid);
                        dom = AP_QID_QUEUE(device_status[i].qid);
                        /* fresh fetch mkvp from adapter */
                        if (fetch_mkvp(card, dom, mkvp) == 0) {
                                mkvp_cache_update(card, dom, mkvp);
                                if (t->mkvp == mkvp[0])
                                        break;
                                if (t->mkvp == mkvp[1] && oi < 0)
                                        oi = i;
                        }
                }
                if (i >= MAX_ZDEV_ENTRIES_EXT && oi >= 0) {
                        /* old mkvp matched, use this card then */
                        card = AP_QID_CARD(device_status[oi].qid);
                        dom = AP_QID_QUEUE(device_status[oi].qid);
                }
        }
        if (i < MAX_ZDEV_ENTRIES_EXT || oi >= 0) {
                if (pcardnr)
                        *pcardnr = card;
                if (pdomain)
                        *pdomain = dom;
                rc = 0;
        } else
                rc = -ENODEV;

        kfree(device_status);
        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);

/*
 * Verify key and give back some info about the key.
 */
int pkey_verifykey(const struct pkey_seckey *seckey,
                   u16 *pcardnr, u16 *pdomain,
                   u16 *pkeysize, u32 *pattributes)
{
        struct secaeskeytoken *t = (struct secaeskeytoken *) seckey;
        u16 cardnr, domain;
        u64 mkvp[2];
        int rc;

        /* check the secure key for valid AES secure key */
        rc = check_secaeskeytoken((u8 *) seckey, 0);
        if (rc)
                goto out;
        if (pattributes)
                *pattributes = PKEY_VERIFY_ATTR_AES;
        if (pkeysize)
                *pkeysize = t->bitsize;

        /* try to find a card which can handle this key */
        rc = pkey_findcard(seckey, &cardnr, &domain, 1);
        if (rc)
                goto out;

        /* check mkvp for old mkvp match */
        rc = mkvp_cache_fetch(cardnr, domain, mkvp);
        if (rc)
                goto out;
        if (t->mkvp == mkvp[1]) {
                DEBUG_DBG("pkey_verifykey secure key has old mkvp\n");
                if (pattributes)
                        *pattributes |= PKEY_VERIFY_ATTR_OLD_MKVP;
        }

        if (pcardnr)
                *pcardnr = cardnr;
        if (pdomain)
                *pdomain = domain;

out:
        DEBUG_DBG("pkey_verifykey rc=%d\n", rc);
        return rc;
}
EXPORT_SYMBOL(pkey_verifykey);

/*
 * 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;
        }
        case PKEY_VERIFYKEY: {
                struct pkey_verifykey __user *uvk = (void __user *) arg;
                struct pkey_verifykey kvk;

                if (copy_from_user(&kvk, uvk, sizeof(kvk)))
                        return -EFAULT;
                rc = pkey_verifykey(&kvk.seckey, &kvk.cardnr, &kvk.domain,
                                    &kvk.keysize, &kvk.attributes);
                DEBUG_DBG("pkey_ioctl pkey_verifykey()=%d\n", rc);
                if (rc)
                        break;
                if (copy_to_user(uvk, &kvk, sizeof(kvk)))
                        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
 */
static 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);