s390/zcrypt: new sysfs attributes serialnr and mkvps

This patch extends the sysfs interface with two new attributes for the
CEX4, CEX5 and CEX6 crypto cards/queues in coprocessor ('CCA') mode:
  /sys/devices/ap/cardxx/serialnr
  /sys/devices/ap/cardxx/xx.yyyy/mkvps

The serialnr attribute is card based and shows the 8 character ASCII
serial number string which should unique identify the card.

The mkvps is queue based and displays 3 lines of information about the
new, current and old master key register:
  AES NEW: <new_aes_mk_state> <new_aes_mk_mkvp>
  AES CUR: <cur_aes_mk_state> <cur_aes_mk_mkvp>
  AES OLD: <old_aes_mk_state> <old_aes_mk_mkvp>
with
  <new_aes_mk_state>: 'empty' or 'partial' or 'full'
  <cur_aes_mk_state>: 'valid' or 'invalid'
  <old_aes_mk_state>: 'valid' or 'invalid'
  <new_aes_mk_mkvp>, <cur_aes_mk_mkvp>, <old_aes_mk_mkvp>
    8 byte hex string with leading 0x
MKVP means Master Key Verification Pattern and is a folded hash over
the key value. Only the states 'full' and 'valid' result in displaying
a useful mkvp, otherwise a mkvp of all bytes zero is shown. If for any
reason the FQ fails and the (cached) information is not available, the
state '-' will be shown with the mkvp value also '-'. The values shown
here are the very same as the cca panel tools displays. As of now only
the AES master keys states and verification patterns are shown. A CCA
APQN also has similar master key registers for DES, RSA and ECC. So
the content of this attribute may get extended.

Reading the sysfs attribute automatically triggers an FQ CPRB to be
sent to the queue as long as the queue is (soft-) online. For the
serialnr attribute the queue with the default domain id is addressed
(if available and valid). This is reasonable as it is assumed that
this sysfs interface is not performance critical and on the other side
a master key change should be visiable as soon as possible. When a
queue is (soft-) offline however, the cached values are displayed. If
no cached values are available, the serial number string will be empty
and the mkvp lines will show state '-' and mkvp value '-'.

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, 105 insertions, 1 deletions

diff --git a/drivers/s390/crypto/zcrypt_cex4.c b/drivers/s390/crypto/zcrypt_cex4.c
index 582ffa7e0f18..f58d8dec19dc 100644
--- a/drivers/s390/crypto/zcrypt_cex4.c
+++ b/drivers/s390/crypto/zcrypt_cex4.c
@@ -18,6 +18,7 @@
 #include "zcrypt_msgtype50.h"
 #include "zcrypt_error.h"
 #include "zcrypt_cex4.h"
+#include "zcrypt_ccamisc.h"
 
 #define CEX4A_MIN_MOD_SIZE	  1	/*    8 bits	*/
 #define CEX4A_MAX_MOD_SIZE_2K	256	/* 2048 bits	*/
@@ -65,6 +66,85 @@ static struct ap_device_id zcrypt_cex4_queue_ids[] = {
 
 MODULE_DEVICE_TABLE(ap, zcrypt_cex4_queue_ids);
 
+/*
+ * CCA card addditional device attributes
+ */
+static ssize_t serialnr_show(struct device *dev,
+			     struct device_attribute *attr,
+			     char *buf)
+{
+	struct cca_info ci;
+	struct ap_card *ac = to_ap_card(dev);
+	struct zcrypt_card *zc = ac->private;
+
+	memset(&ci, 0, sizeof(ci));
+
+	if (ap_domain_index >= 0)
+		cca_get_info(ac->id, ap_domain_index, &ci, zc->online);
+
+	return snprintf(buf, PAGE_SIZE, "%s\n", ci.serial);
+}
+static DEVICE_ATTR_RO(serialnr);
+
+static struct attribute *cca_card_attrs[] = {
+	&dev_attr_serialnr.attr,
+	NULL,
+};
+
+static const struct attribute_group cca_card_attr_group = {
+	.attrs = cca_card_attrs,
+};
+
+/*
+ * CCA queue addditional device attributes
+ */
+static ssize_t mkvps_show(struct device *dev,
+			  struct device_attribute *attr,
+			  char *buf)
+{
+	int n = 0;
+	struct cca_info ci;
+	struct zcrypt_queue *zq = to_ap_queue(dev)->private;
+	static const char * const cao_state[] = { "invalid", "valid" };
+	static const char * const new_state[] = { "empty", "partial", "full" };
+
+	memset(&ci, 0, sizeof(ci));
+
+	cca_get_info(AP_QID_CARD(zq->queue->qid),
+		     AP_QID_QUEUE(zq->queue->qid),
+		     &ci, zq->online);
+
+	if (ci.new_mk_state >= '1' && ci.new_mk_state <= '3')
+		n = snprintf(buf, PAGE_SIZE, "AES NEW: %s 0x%016llx\n",
+			     new_state[ci.new_mk_state - '1'], ci.new_mkvp);
+	else
+		n = snprintf(buf, PAGE_SIZE, "AES NEW: - -\n");
+
+	if (ci.cur_mk_state >= '1' && ci.cur_mk_state <= '2')
+		n += snprintf(buf + n, PAGE_SIZE - n, "AES CUR: %s 0x%016llx\n",
+			      cao_state[ci.cur_mk_state - '1'], ci.cur_mkvp);
+	else
+		n += snprintf(buf + n, PAGE_SIZE - n, "AES CUR: - -\n");
+
+	if (ci.old_mk_state >= '1' && ci.old_mk_state <= '2')
+		n += snprintf(buf + n, PAGE_SIZE - n, "AES OLD: %s 0x%016llx\n",
+			      cao_state[ci.old_mk_state - '1'], ci.old_mkvp);
+	else
+		n += snprintf(buf + n, PAGE_SIZE - n, "AES OLD: - -\n");
+
+	return n;
+}
+static DEVICE_ATTR_RO(mkvps);
+
+static struct attribute *cca_queue_attrs[] = {
+	&dev_attr_mkvps.attr,
+	NULL,
+};
+
+static const struct attribute_group cca_queue_attr_group = {
+	.attrs = cca_queue_attrs,
+};
+
 /**
  * Probe function for CEX4/CEX5/CEX6 card device. It always
  * accepts the AP device since the bus_match already checked
@@ -194,8 +274,17 @@ static int zcrypt_cex4_card_probe(struct ap_device *ap_dev)
 	if (rc) {
 		ac->private = NULL;
 		zcrypt_card_free(zc);
+		goto out;
 	}
 
+	if (ap_test_bit(&ac->functions, AP_FUNC_COPRO)) {
+		rc = sysfs_create_group(&ap_dev->device.kobj,
+					&cca_card_attr_group);
+		if (rc)
+			zcrypt_card_unregister(zc);
+	}
+
+out:
 	return rc;
 }
 
@@ -205,8 +294,11 @@ static int zcrypt_cex4_card_probe(struct ap_device *ap_dev)
  */
 static void zcrypt_cex4_card_remove(struct ap_device *ap_dev)
 {
-	struct zcrypt_card *zc = to_ap_card(&ap_dev->device)->private;
+	struct ap_card *ac = to_ap_card(&ap_dev->device);
+	struct zcrypt_card *zc = ac->private;
 
+	if (ap_test_bit(&ac->functions, AP_FUNC_COPRO))
+		sysfs_remove_group(&ap_dev->device.kobj, &cca_card_attr_group);
 	if (zc)
 		zcrypt_card_unregister(zc);
 }
@@ -251,6 +343,7 @@ static int zcrypt_cex4_queue_probe(struct ap_device *ap_dev)
 	} else {
 		return -ENODEV;
 	}
+
 	zq->queue = aq;
 	zq->online = 1;
 	atomic_set(&zq->load, 0);
@@ -261,8 +354,17 @@ static int zcrypt_cex4_queue_probe(struct ap_device *ap_dev)
 	if (rc) {
 		aq->private = NULL;
 		zcrypt_queue_free(zq);
+		goto out;
+	}
+
+	if (ap_test_bit(&aq->card->functions, AP_FUNC_COPRO)) {
+		rc = sysfs_create_group(&ap_dev->device.kobj,
+					&cca_queue_attr_group);
+		if (rc)
+			zcrypt_queue_unregister(zq);
 	}
 
+out:
 	return rc;
 }
 
@@ -275,6 +377,8 @@ static void zcrypt_cex4_queue_remove(struct ap_device *ap_dev)
 	struct ap_queue *aq = to_ap_queue(&ap_dev->device);
 	struct zcrypt_queue *zq = aq->private;
 
+	if (ap_test_bit(&aq->card->functions, AP_FUNC_COPRO))
+		sysfs_remove_group(&ap_dev->device.kobj, &cca_queue_attr_group);
 	if (zq)
 		zcrypt_queue_unregister(zq);
 }