1 files changed, 248 insertions, 0 deletions
diff --git a/drivers/s390/crypto/zcrypt_cca_key.h b/drivers/s390/crypto/zcrypt_cca_key.h
new file mode 100644
index 000000000..f09bb8507
--- /dev/null
+++ b/drivers/s390/crypto/zcrypt_cca_key.h
@@ -0,0 +1,248 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ *  Copyright IBM Corp. 2001, 2006
+ *  Author(s): Robert Burroughs
+ *	       Eric Rossman (edrossma@us.ibm.com)
+ *
+ *  Hotplug & misc device support: Jochen Roehrig (roehrig@de.ibm.com)
+ *  Major cleanup & driver split: Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#ifndef _ZCRYPT_CCA_KEY_H_
+#define _ZCRYPT_CCA_KEY_H_
+
+struct T6_keyBlock_hdr {
+	unsigned short blen;
+	unsigned short ulen;
+	unsigned short flags;
+};
+
+/**
+ * mapping for the cca private ME key token.
+ * Three parts of interest here: the header, the private section and
+ * the public section.
+ *
+ * mapping for the cca key token header
+ */
+struct cca_token_hdr {
+	unsigned char  token_identifier;
+	unsigned char  version;
+	unsigned short token_length;
+	unsigned char  reserved[4];
+} __packed;
+
+#define CCA_TKN_HDR_ID_EXT 0x1E
+
+#define CCA_PVT_USAGE_ALL 0x80
+
+/**
+ * mapping for the cca public section
+ * In a private key, the modulus doesn't appear in the public
+ * section. So, an arbitrary public exponent of 0x010001 will be
+ * used, for a section length of 0x0F always.
+ */
+struct cca_public_sec {
+	unsigned char  section_identifier;
+	unsigned char  version;
+	unsigned short section_length;
+	unsigned char  reserved[2];
+	unsigned short exponent_len;
+	unsigned short modulus_bit_len;
+	unsigned short modulus_byte_len;    /* In a private key, this is 0 */
+} __packed;
+
+/**
+ * mapping for the cca private CRT key 'token'
+ * The first three parts (the only parts considered in this release)
+ * are: the header, the private section and the public section.
+ * The header and public section are the same as for the
+ * struct cca_private_ext_ME
+ *
+ * Following the structure are the quantities p, q, dp, dq, u, pad,
+ * and modulus, in that order, where pad_len is the modulo 8
+ * complement of the residue modulo 8 of the sum of
+ * (p_len + q_len + dp_len + dq_len + u_len).
+ */
+struct cca_pvt_ext_CRT_sec {
+	unsigned char  section_identifier;
+	unsigned char  version;
+	unsigned short section_length;
+	unsigned char  private_key_hash[20];
+	unsigned char  reserved1[4];
+	unsigned char  key_format;
+	unsigned char  reserved2;
+	unsigned char  key_name_hash[20];
+	unsigned char  key_use_flags[4];
+	unsigned short p_len;
+	unsigned short q_len;
+	unsigned short dp_len;
+	unsigned short dq_len;
+	unsigned short u_len;
+	unsigned short mod_len;
+	unsigned char  reserved3[4];
+	unsigned short pad_len;
+	unsigned char  reserved4[52];
+	unsigned char  confounder[8];
+} __packed;
+
+#define CCA_PVT_EXT_CRT_SEC_ID_PVT 0x08
+#define CCA_PVT_EXT_CRT_SEC_FMT_CL 0x40
+
+/**
+ * Set up private key fields of a type6 MEX message. The _pad variant
+ * strips leading zeroes from the b_key.
+ * Note that all numerics in the key token are big-endian,
+ * while the entries in the key block header are little-endian.
+ *
+ * @mex: pointer to user input data
+ * @p: pointer to memory area for the key
+ *
+ * Returns the size of the key area or negative errno value.
+ */
+static inline int zcrypt_type6_mex_key_en(struct ica_rsa_modexpo *mex, void *p)
+{
+	static struct cca_token_hdr static_pub_hdr = {
+		.token_identifier	=  0x1E,
+	};
+	static struct cca_public_sec static_pub_sec = {
+		.section_identifier	=  0x04,
+	};
+	struct {
+		struct T6_keyBlock_hdr t6_hdr;
+		struct cca_token_hdr pubHdr;
+		struct cca_public_sec pubSec;
+		char exponent[0];
+	} __packed *key = p;
+	unsigned char *temp;
+	int i;
+
+	/*
+	 * The inputdatalength was a selection criteria in the dispatching
+	 * function zcrypt_rsa_modexpo(). However, do a plausibility check
+	 * here to make sure the following copy_from_user() can't be utilized
+	 * to compromise the system.
+	 */
+	if (WARN_ON_ONCE(mex->inputdatalength > 512))
+		return -EINVAL;
+
+	memset(key, 0, sizeof(*key));
+
+	key->pubHdr = static_pub_hdr;
+	key->pubSec = static_pub_sec;
+
+	/* key parameter block */
+	temp = key->exponent;
+	if (copy_from_user(temp, mex->b_key, mex->inputdatalength))
+		return -EFAULT;
+	/* Strip leading zeroes from b_key. */
+	for (i = 0; i < mex->inputdatalength; i++)
+		if (temp[i])
+			break;
+	if (i >= mex->inputdatalength)
+		return -EINVAL;
+	memmove(temp, temp + i, mex->inputdatalength - i);
+	temp += mex->inputdatalength - i;
+	/* modulus */
+	if (copy_from_user(temp, mex->n_modulus, mex->inputdatalength))
+		return -EFAULT;
+
+	key->pubSec.modulus_bit_len = 8 * mex->inputdatalength;
+	key->pubSec.modulus_byte_len = mex->inputdatalength;
+	key->pubSec.exponent_len = mex->inputdatalength - i;
+	key->pubSec.section_length = sizeof(key->pubSec) +
+					2*mex->inputdatalength - i;
+	key->pubHdr.token_length =
+		key->pubSec.section_length + sizeof(key->pubHdr);
+	key->t6_hdr.ulen = key->pubHdr.token_length + 4;
+	key->t6_hdr.blen = key->pubHdr.token_length + 6;
+	return sizeof(*key) + 2*mex->inputdatalength - i;
+}
+
+/**
+ * Set up private key fields of a type6 CRT message.
+ * Note that all numerics in the key token are big-endian,
+ * while the entries in the key block header are little-endian.
+ *
+ * @mex: pointer to user input data
+ * @p: pointer to memory area for the key
+ *
+ * Returns the size of the key area or -EFAULT
+ */
+static inline int zcrypt_type6_crt_key(struct ica_rsa_modexpo_crt *crt, void *p)
+{
+	static struct cca_public_sec static_cca_pub_sec = {
+		.section_identifier = 4,
+		.section_length = 0x000f,
+		.exponent_len = 0x0003,
+	};
+	static char pk_exponent[3] = { 0x01, 0x00, 0x01 };
+	struct {
+		struct T6_keyBlock_hdr t6_hdr;
+		struct cca_token_hdr token;
+		struct cca_pvt_ext_CRT_sec pvt;
+		char key_parts[0];
+	} __packed *key = p;
+	struct cca_public_sec *pub;
+	int short_len, long_len, pad_len, key_len, size;
+
+	/*
+	 * The inputdatalength was a selection criteria in the dispatching
+	 * function zcrypt_rsa_crt(). However, do a plausibility check
+	 * here to make sure the following copy_from_user() can't be utilized
+	 * to compromise the system.
+	 */
+	if (WARN_ON_ONCE(crt->inputdatalength > 512))
+		return -EINVAL;
+
+	memset(key, 0, sizeof(*key));
+
+	short_len = (crt->inputdatalength + 1) / 2;
+	long_len = short_len + 8;
+	pad_len = -(3*long_len + 2*short_len) & 7;
+	key_len = 3*long_len + 2*short_len + pad_len + crt->inputdatalength;
+	size = sizeof(*key) + key_len + sizeof(*pub) + 3;
+
+	/* parameter block.key block */
+	key->t6_hdr.blen = size;
+	key->t6_hdr.ulen = size - 2;
+
+	/* key token header */
+	key->token.token_identifier = CCA_TKN_HDR_ID_EXT;
+	key->token.token_length = size - 6;
+
+	/* private section */
+	key->pvt.section_identifier = CCA_PVT_EXT_CRT_SEC_ID_PVT;
+	key->pvt.section_length = sizeof(key->pvt) + key_len;
+	key->pvt.key_format = CCA_PVT_EXT_CRT_SEC_FMT_CL;
+	key->pvt.key_use_flags[0] = CCA_PVT_USAGE_ALL;
+	key->pvt.p_len = key->pvt.dp_len = key->pvt.u_len = long_len;
+	key->pvt.q_len = key->pvt.dq_len = short_len;
+	key->pvt.mod_len = crt->inputdatalength;
+	key->pvt.pad_len = pad_len;
+
+	/* key parts */
+	if (copy_from_user(key->key_parts, crt->np_prime, long_len) ||
+	    copy_from_user(key->key_parts + long_len,
+					crt->nq_prime, short_len) ||
+	    copy_from_user(key->key_parts + long_len + short_len,
+					crt->bp_key, long_len) ||
+	    copy_from_user(key->key_parts + 2*long_len + short_len,
+					crt->bq_key, short_len) ||
+	    copy_from_user(key->key_parts + 2*long_len + 2*short_len,
+					crt->u_mult_inv, long_len))
+		return -EFAULT;
+	memset(key->key_parts + 3*long_len + 2*short_len + pad_len,
+	       0xff, crt->inputdatalength);
+	pub = (struct cca_public_sec *)(key->key_parts + key_len);
+	*pub = static_cca_pub_sec;
+	pub->modulus_bit_len = 8 * crt->inputdatalength;
+	/*
+	 * In a private key, the modulus doesn't appear in the public
+	 * section. So, an arbitrary public exponent of 0x010001 will be
+	 * used.
+	 */
+	memcpy((char *) (pub + 1), pk_exponent, 3);
+	return size;
+}
+
+#endif /* _ZCRYPT_CCA_KEY_H_ */