s390/zcrypt: remove unused ancient padding code

There was some ancient code which padded the results of
a clear key ME or CRT operation with some PKCS 1.2 header.
According to the comment this was only needed by crypto
cards older than the CEX2. These cards are not supported
any more and so this patch removes this obscure result
padding code.
Signed-off-by: Harald Freudenberger <freude@linux.ibm.com>
Reviewed-by: Juergen Christ <jchrist@linux.ibm.com>
Reviewed-by: Holger Dengler <dengler@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

drivers/s390/crypto/zcrypt_msgtype6.c

@@ -566,8 +566,8 @@ struct type86x_reply {
 	struct type86_fmt2_ext fmt2;
 	struct CPRBX cprbx;
 	unsigned char pad[4];	/* 4 byte function code/rules block ? */
-	unsigned short length;
-	char text[];
+	unsigned short length;	/* length of data including length field size */
+	char data[];
 } __packed;
 
 struct type86_ep11_reply {
@@ -581,45 +581,9 @@ static int convert_type86_ica(struct zcrypt_queue *zq,
 			      char __user *outputdata,
 			      unsigned int outputdatalength)
 {
-	static unsigned char static_pad[] = {
-		0x00, 0x02,
-		0x1B, 0x7B, 0x5D, 0xB5, 0x75, 0x01, 0x3D, 0xFD,
-		0x8D, 0xD1, 0xC7, 0x03, 0x2D, 0x09, 0x23, 0x57,
-		0x89, 0x49, 0xB9, 0x3F, 0xBB, 0x99, 0x41, 0x5B,
-		0x75, 0x21, 0x7B, 0x9D, 0x3B, 0x6B, 0x51, 0x39,
-		0xBB, 0x0D, 0x35, 0xB9, 0x89, 0x0F, 0x93, 0xA5,
-		0x0B, 0x47, 0xF1, 0xD3, 0xBB, 0xCB, 0xF1, 0x9D,
-		0x23, 0x73, 0x71, 0xFF, 0xF3, 0xF5, 0x45, 0xFB,
-		0x61, 0x29, 0x23, 0xFD, 0xF1, 0x29, 0x3F, 0x7F,
-		0x17, 0xB7, 0x1B, 0xA9, 0x19, 0xBD, 0x57, 0xA9,
-		0xD7, 0x95, 0xA3, 0xCB, 0xED, 0x1D, 0xDB, 0x45,
-		0x7D, 0x11, 0xD1, 0x51, 0x1B, 0xED, 0x71, 0xE9,
-		0xB1, 0xD1, 0xAB, 0xAB, 0x21, 0x2B, 0x1B, 0x9F,
-		0x3B, 0x9F, 0xF7, 0xF7, 0xBD, 0x63, 0xEB, 0xAD,
-		0xDF, 0xB3, 0x6F, 0x5B, 0xDB, 0x8D, 0xA9, 0x5D,
-		0xE3, 0x7D, 0x77, 0x49, 0x47, 0xF5, 0xA7, 0xFD,
-		0xAB, 0x2F, 0x27, 0x35, 0x77, 0xD3, 0x49, 0xC9,
-		0x09, 0xEB, 0xB1, 0xF9, 0xBF, 0x4B, 0xCB, 0x2B,
-		0xEB, 0xEB, 0x05, 0xFF, 0x7D, 0xC7, 0x91, 0x8B,
-		0x09, 0x83, 0xB9, 0xB9, 0x69, 0x33, 0x39, 0x6B,
-		0x79, 0x75, 0x19, 0xBF, 0xBB, 0x07, 0x1D, 0xBD,
-		0x29, 0xBF, 0x39, 0x95, 0x93, 0x1D, 0x35, 0xC7,
-		0xC9, 0x4D, 0xE5, 0x97, 0x0B, 0x43, 0x9B, 0xF1,
-		0x16, 0x93, 0x03, 0x1F, 0xA5, 0xFB, 0xDB, 0xF3,
-		0x27, 0x4F, 0x27, 0x61, 0x05, 0x1F, 0xB9, 0x23,
-		0x2F, 0xC3, 0x81, 0xA9, 0x23, 0x71, 0x55, 0x55,
-		0xEB, 0xED, 0x41, 0xE5, 0xF3, 0x11, 0xF1, 0x43,
-		0x69, 0x03, 0xBD, 0x0B, 0x37, 0x0F, 0x51, 0x8F,
-		0x0B, 0xB5, 0x89, 0x5B, 0x67, 0xA9, 0xD9, 0x4F,
-		0x01, 0xF9, 0x21, 0x77, 0x37, 0x73, 0x79, 0xC5,
-		0x7F, 0x51, 0xC1, 0xCF, 0x97, 0xA1, 0x75, 0xAD,
-		0x35, 0x9D, 0xD3, 0xD3, 0xA7, 0x9D, 0x5D, 0x41,
-		0x6F, 0x65, 0x1B, 0xCF, 0xA9, 0x87, 0x91, 0x09
-	};
 	struct type86x_reply *msg = reply->msg;
 	unsigned short service_rc, service_rs;
-	unsigned int reply_len, pad_len;
-	char *data;
+	unsigned int data_len;
 
 	service_rc = msg->cprbx.ccp_rtcode;
 	if (unlikely(service_rc != 0)) {
@@ -647,32 +611,12 @@ static int convert_type86_ica(struct zcrypt_queue *zq,
 		ap_send_online_uevent(&zq->queue->ap_dev, zq->online);
 		return -EAGAIN;
 	}
-	data = msg->text;
-	reply_len = msg->length - 2;
-	if (reply_len > outputdatalength)
-		return -EINVAL;
-	/*
-	 * For all encipher requests, the length of the ciphertext (reply_len)
-	 * will always equal the modulus length. For MEX decipher requests
-	 * the output needs to get padded. Minimum pad size is 10.
-	 *
-	 * Currently, the cases where padding will be added is for:
-	 * - PCIXCC_MCL2 using a CRT form token (since PKD didn't support
-	 *   ZERO-PAD and CRT is only supported for PKD requests)
-	 * - PCICC, always
-	 */
-	pad_len = outputdatalength - reply_len;
-	if (pad_len > 0) {
-		if (pad_len < 10)
-			return -EINVAL;
-		/* 'restore' padding left in the CEXXC card. */
-		if (copy_to_user(outputdata, static_pad, pad_len - 1))
-			return -EFAULT;
-		if (put_user(0, outputdata + pad_len - 1))
-			return -EFAULT;
-	}
+	data_len = msg->length - sizeof(msg->length);
+	if (data_len > outputdatalength)
+		return -EMSGSIZE;
+
 	/* Copy the crypto response to user space. */
-	if (copy_to_user(outputdata + pad_len, data, reply_len))
+	if (copy_to_user(outputdata, msg->data, data_len))
 		return -EFAULT;
 	return 0;
 }