s390/pkey: support CCA and EP11 secure ECC private keys

This patch extends the pkey kernel module to support CCA
and EP11 secure ECC (private) keys as source for deriving
ECC protected (private) keys.

There is yet another new ioctl to support this: PKEY_KBLOB2PROTK3
can handle all the old keys plus CCA and EP11 secure ECC keys.
For details see ioctl description in pkey.h.

The CPACF unit currently only supports a subset of 5
different ECC curves (P-256, P-384, P-521, ED25519, ED448) and
so only keys of this curve type can be transformed into
protected keys. However, the pkey and the cca/ep11 low level
functions do not check this but simple pass-through the key
blob to the firmware onto the crypto cards. So most likely
the failure will be a response carrying an error code
resulting in user space errno value EIO instead of EINVAL.

Deriving a protected key from an EP11 ECC secure key
requires a CEX7 in EP11 mode. Deriving a protected key from
an CCA ECC secure key requires a CEX7 in CCA mode.

Together with this new ioctl the ioctls for querying lists
of apqns (PKEY_APQNS4K and PKEY_APQNS4KT) have been extended
to support EP11 and CCA ECC secure key type and key blobs.

Together with this ioctl there comes a new struct ep11kblob_header
which is to be prepended onto the EP11 key blob. See details
in pkey.h for the fields in there. The older EP11 AES key blob
with some info stored in the (unused) session field is also
supported with this new ioctl.

Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Ingo Franzki <ifranzki@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

1 files changed, 42 insertions, 2 deletions

diff --git a/drivers/s390/crypto/zcrypt_ccamisc.h b/drivers/s390/crypto/zcrypt_ccamisc.h
index 4d88a1d6af21..e7105443d5cb 100644
--- a/drivers/s390/crypto/zcrypt_ccamisc.h
+++ b/drivers/s390/crypto/zcrypt_ccamisc.h
@@ -14,8 +14,9 @@
 #include <asm/pkey.h>
 
 /* Key token types */
-#define TOKTYPE_NON_CCA		0x00 /* Non-CCA key token */
-#define TOKTYPE_CCA_INTERNAL	0x01 /* CCA internal key token */
+#define TOKTYPE_NON_CCA		 0x00 /* Non-CCA key token */
+#define TOKTYPE_CCA_INTERNAL	 0x01 /* CCA internal sym key token */
+#define TOKTYPE_CCA_INTERNAL_PKA 0x1f /* CCA internal asym key token */
 
 /* For TOKTYPE_NON_CCA: */
 #define TOKVER_PROTECTED_KEY	0x01 /* Protected key token */
@@ -93,6 +94,31 @@ struct cipherkeytoken {
 	u8  vdata[]; /* variable part data follows */
 } __packed;
 
+/* inside view of an CCA secure ECC private key */
+struct eccprivkeytoken {
+	u8  type;     /* 0x1f for internal asym key token */
+	u8  version;  /* should be 0x00 */
+	u16 len;      /* total key token length in bytes */
+	u8  res1[4];
+	u8  secid;    /* 0x20 for ECC priv key section marker */
+	u8  secver;   /* section version */
+	u16 seclen;   /* section length */
+	u8  wtype;    /* wrapping method, 0x00 clear, 0x01 AES */
+	u8  htype;    /* hash method, 0x02 for SHA-256 */
+	u8  res2[2];
+	u8  kutc;     /* key usage and translation control */
+	u8  ctype;    /* curve type */
+	u8  kfs;      /* key format and security */
+	u8  ksrc;     /* key source */
+	u16 pbitlen;  /* length of prime p in bits */
+	u16 ibmadlen; /* IBM associated data length in bytes */
+	u64 mkvp;     /* master key verification pattern */
+	u8  opk[48];  /* encrypted object protection key data */
+	u16 adatalen; /* associated data length in bytes */
+	u16 fseclen;  /* formated section length in bytes */
+	u8  more_data[]; /* more data follows */
+} __packed;
+
 /* Some defines for the CCA AES cipherkeytoken kmf1 field */
 #define KMF1_XPRT_SYM  0x8000
 #define KMF1_XPRT_UASY 0x4000
@@ -123,6 +149,14 @@ int cca_check_secaescipherkey(debug_info_t *dbg, int dbflvl,
 			      int checkcpacfexport);
 
 /*
+ * Simple check if the token is a valid CCA secure ECC private
+ * key token. Returns 0 on success or errno value on failure.
+ */
+int cca_check_sececckeytoken(debug_info_t *dbg, int dbflvl,
+			     const u8 *token, size_t keysize,
+			     int checkcpacfexport);
+
+/*
  * Generate (random) CCA AES DATA secure key.
  */
 int cca_genseckey(u16 cardnr, u16 domain, u32 keybitsize, u8 *seckey);
@@ -159,6 +193,12 @@ int cca_clr2cipherkey(u16 cardnr, u16 domain, u32 keybitsize, u32 keygenflags,
 		      const u8 *clrkey, u8 *keybuf, size_t *keybufsize);
 
 /*
+ * Derive proteced key from CCA ECC secure private key.
+ */
+int cca_ecc2protkey(u16 cardnr, u16 domain, const u8 *key,
+		    u8 *protkey, u32 *protkeylen, u32 *protkeytype);
+
+/*
  * Query cryptographic facility from CCA adapter
  */
 int cca_query_crypto_facility(u16 cardnr, u16 domain,