[S390] zcrypt secure key cryptography extension.

Allow the user space to send extended cprb messages directly to the
PCIXCC / CEX2C cards. This allows the CCA library to construct special
crypto requests that use "secure" keys that are stored on the card.

Signed-off-by: Ralph Wuerthner <rwuerthn@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 250 insertions, 13 deletions

diff --git a/drivers/s390/crypto/zcrypt_pcixcc.c b/drivers/s390/crypto/zcrypt_pcixcc.c
index 6064cf58be43..2da8b9381407 100644
--- a/drivers/s390/crypto/zcrypt_pcixcc.c
+++ b/drivers/s390/crypto/zcrypt_pcixcc.c
@@ -1,7 +1,7 @@
 /*
  *  linux/drivers/s390/crypto/zcrypt_pcixcc.c
  *
- *  zcrypt 2.0.0
+ *  zcrypt 2.1.0
  *
  *  Copyright (C)  2001, 2006 IBM Corporation
  *  Author(s): Robert Burroughs
@@ -60,6 +60,15 @@
 
 #define PCIXCC_CLEANUP_TIME     (15*HZ)
 
+#define CEIL4(x) ((((x)+3)/4)*4)
+
+struct response_type {
+        struct completion work;
+        int type;
+};
+#define PCIXCC_RESPONSE_TYPE_ICA  0
+#define PCIXCC_RESPONSE_TYPE_XCRB 1
+
 static struct ap_device_id zcrypt_pcixcc_ids[] = {
         { AP_DEVICE(AP_DEVICE_TYPE_PCIXCC) },
         { AP_DEVICE(AP_DEVICE_TYPE_CEX2C) },
@@ -244,6 +253,108 @@ static int ICACRT_msg_to_type6CRT_msgX(struct zcrypt_device *zdev,
 }
 
 /**
+ * Convert a XCRB message to a type6 CPRB message.
+ *
+ * @zdev: crypto device pointer
+ * @ap_msg: pointer to AP message
+ * @xcRB: pointer to user input data
+ *
+ * Returns 0 on success or -EFAULT.
+ */
+struct type86_fmt2_msg {
+        struct type86_hdr hdr;
+        struct type86_fmt2_ext fmt2;
+} __attribute__((packed));
+
+static int XCRB_msg_to_type6CPRB_msgX(struct zcrypt_device *zdev,
+                                       struct ap_message *ap_msg,
+                                       struct ica_xcRB *xcRB)
+{
+        static struct type6_hdr static_type6_hdrX = {
+                .type           =  0x06,
+                .offset1        =  0x00000058,
+        };
+        struct {
+                struct type6_hdr hdr;
+                struct ica_CPRBX cprbx;
+        } __attribute__((packed)) *msg = ap_msg->message;
+
+        int rcblen = CEIL4(xcRB->request_control_blk_length);
+        int replylen;
+        char *req_data = ap_msg->message + sizeof(struct type6_hdr) + rcblen;
+        char *function_code;
+
+        /* length checks */
+        ap_msg->length = sizeof(struct type6_hdr) +
+                CEIL4(xcRB->request_control_blk_length) +
+                xcRB->request_data_length;
+        if (ap_msg->length > PCIXCC_MAX_XCRB_MESSAGE_SIZE) {
+                PRINTK("Combined message is too large (%ld/%d/%d).\n",
+                    sizeof(struct type6_hdr),
+                    xcRB->request_control_blk_length,
+                    xcRB->request_data_length);
+                return -EFAULT;
+        }
+        if (CEIL4(xcRB->reply_control_blk_length) >
+            PCIXCC_MAX_XCRB_REPLY_SIZE) {
+                PDEBUG("Reply CPRB length is too large (%d).\n",
+                    xcRB->request_control_blk_length);
+                return -EFAULT;
+        }
+        if (CEIL4(xcRB->reply_data_length) > PCIXCC_MAX_XCRB_DATA_SIZE) {
+                PDEBUG("Reply data block length is too large (%d).\n",
+                    xcRB->reply_data_length);
+                return -EFAULT;
+        }
+        replylen = CEIL4(xcRB->reply_control_blk_length) +
+                CEIL4(xcRB->reply_data_length) +
+                sizeof(struct type86_fmt2_msg);
+        if (replylen > PCIXCC_MAX_XCRB_RESPONSE_SIZE) {
+                PDEBUG("Reply CPRB + data block > PCIXCC_MAX_XCRB_RESPONSE_SIZE"
+                       " (%d/%d/%d).\n",
+                       sizeof(struct type86_fmt2_msg),
+                       xcRB->reply_control_blk_length,
+                       xcRB->reply_data_length);
+                xcRB->reply_control_blk_length = PCIXCC_MAX_XCRB_RESPONSE_SIZE -
+                        (sizeof(struct type86_fmt2_msg) +
+                            CEIL4(xcRB->reply_data_length));
+                PDEBUG("Capping Reply CPRB length at %d\n",
+                       xcRB->reply_control_blk_length);
+        }
+
+        /* prepare type6 header */
+        msg->hdr = static_type6_hdrX;
+        memcpy(msg->hdr.agent_id , &(xcRB->agent_ID), sizeof(xcRB->agent_ID));
+        msg->hdr.ToCardLen1 = xcRB->request_control_blk_length;
+        if (xcRB->request_data_length) {
+                msg->hdr.offset2 = msg->hdr.offset1 + rcblen;
+                msg->hdr.ToCardLen2 = xcRB->request_data_length;
+        }
+        msg->hdr.FromCardLen1 = xcRB->reply_control_blk_length;
+        msg->hdr.FromCardLen2 = xcRB->reply_data_length;
+
+        /* prepare CPRB */
+        if (copy_from_user(&(msg->cprbx), xcRB->request_control_blk_addr,
+                    xcRB->request_control_blk_length))
+                return -EFAULT;
+        if (msg->cprbx.cprb_len + sizeof(msg->hdr.function_code) >
+            xcRB->request_control_blk_length) {
+                PDEBUG("cprb_len too large (%d/%d)\n", msg->cprbx.cprb_len,
+                    xcRB->request_control_blk_length);
+                return -EFAULT;
+        }
+        function_code = ((unsigned char *)&msg->cprbx) + msg->cprbx.cprb_len;
+        memcpy(msg->hdr.function_code, function_code, sizeof(msg->hdr.function_code));
+
+        /* copy data block */
+        if (xcRB->request_data_length &&
+            copy_from_user(req_data, xcRB->request_data_address,
+                xcRB->request_data_length))
+                return -EFAULT;
+        return 0;
+}
+
+/**
  * Copy results from a type 86 ICA reply message back to user space.
  *
  * @zdev: crypto device pointer
@@ -363,6 +474,37 @@ static int convert_type86_ica(struct zcrypt_device *zdev,
         return 0;
 }
 
+/**
+ * Copy results from a type 86 XCRB reply message back to user space.
+ *
+ * @zdev: crypto device pointer
+ * @reply: reply AP message.
+ * @xcRB: pointer to XCRB
+ *
+ * Returns 0 on success or -EINVAL, -EFAULT, -EAGAIN in case of an error.
+ */
+static int convert_type86_xcrb(struct zcrypt_device *zdev,
+                               struct ap_message *reply,
+                               struct ica_xcRB *xcRB)
+{
+        struct type86_fmt2_msg *msg = reply->message;
+        char *data = reply->message;
+
+        /* Copy CPRB to user */
+        if (copy_to_user(xcRB->reply_control_blk_addr,
+                data + msg->fmt2.offset1, msg->fmt2.count1))
+                return -EFAULT;
+        xcRB->reply_control_blk_length = msg->fmt2.count1;
+
+        /* Copy data buffer to user */
+        if (msg->fmt2.count2)
+                if (copy_to_user(xcRB->reply_data_addr,
+                        data + msg->fmt2.offset2, msg->fmt2.count2))
+                        return -EFAULT;
+        xcRB->reply_data_length = msg->fmt2.count2;
+        return 0;
+}
+
 static int convert_response_ica(struct zcrypt_device *zdev,
                             struct ap_message *reply,
                             char __user *outputdata,
@@ -391,6 +533,36 @@ static int convert_response_ica(struct zcrypt_device *zdev,
         }
 }
 
+static int convert_response_xcrb(struct zcrypt_device *zdev,
+                            struct ap_message *reply,
+                            struct ica_xcRB *xcRB)
+{
+        struct type86x_reply *msg = reply->message;
+
+        /* Response type byte is the second byte in the response. */
+        switch (((unsigned char *) reply->message)[1]) {
+        case TYPE82_RSP_CODE:
+        case TYPE88_RSP_CODE:
+                xcRB->status = 0x0008044DL; /* HDD_InvalidParm */
+                return convert_error(zdev, reply);
+        case TYPE86_RSP_CODE:
+                if (msg->hdr.reply_code) {
+                        memcpy(&(xcRB->status), msg->fmt2.apfs, sizeof(u32));
+                        return convert_error(zdev, reply);
+                }
+                if (msg->cprbx.cprb_ver_id == 0x02)
+                        return convert_type86_xcrb(zdev, reply, xcRB);
+                /* no break, incorrect cprb version is an unknown response */
+        default: /* Unknown response type, this should NEVER EVER happen */
+                PRINTK("Unrecognized Message Header: %08x%08x\n",
+                       *(unsigned int *) reply->message,
+                       *(unsigned int *) (reply->message+4));
+                xcRB->status = 0x0008044DL; /* HDD_InvalidParm */
+                zdev->online = 0;
+                return -EAGAIN; /* repeat the request on a different device. */
+        }
+}
+
 /**
  * This function is called from the AP bus code after a crypto request
  * "msg" has finished with the reply message "reply".
@@ -407,6 +579,8 @@ static void zcrypt_pcixcc_receive(struct ap_device *ap_dev,
                 .type = TYPE82_RSP_CODE,
                 .reply_code = REP82_ERROR_MACHINE_FAILURE,
         };
+        struct response_type *resp_type =
+                (struct response_type *) msg->private;
         struct type86x_reply *t86r = reply->message;
         int length;
 
@@ -415,12 +589,27 @@ static void zcrypt_pcixcc_receive(struct ap_device *ap_dev,
                 memcpy(msg->message, &error_reply, sizeof(error_reply));
         else if (t86r->hdr.type == TYPE86_RSP_CODE &&
                  t86r->cprbx.cprb_ver_id == 0x02) {
-                length = sizeof(struct type86x_reply) + t86r->length - 2;
-                length = min(PCIXCC_MAX_ICA_RESPONSE_SIZE, length);
-                memcpy(msg->message, reply->message, length);
+                switch (resp_type->type) {
+                case PCIXCC_RESPONSE_TYPE_ICA:
+                        length = sizeof(struct type86x_reply)
+                                + t86r->length - 2;
+                        length = min(PCIXCC_MAX_ICA_RESPONSE_SIZE, length);
+                        memcpy(msg->message, reply->message, length);
+                        break;
+                case PCIXCC_RESPONSE_TYPE_XCRB:
+                        length = t86r->fmt2.offset2 + t86r->fmt2.count2;
+                        length = min(PCIXCC_MAX_XCRB_RESPONSE_SIZE, length);
+                        memcpy(msg->message, reply->message, length);
+                        break;
+                default:
+                        PRINTK("Invalid internal response type: %i\n",
+                            resp_type->type);
+                        memcpy(msg->message, &error_reply,
+                            sizeof error_reply);
+                }
         } else
                 memcpy(msg->message, reply->message, sizeof error_reply);
-        complete((struct completion *) msg->private);
+        complete(&(resp_type->work));
 }
 
 static atomic_t zcrypt_step = ATOMIC_INIT(0);
@@ -436,7 +625,9 @@ static long zcrypt_pcixcc_modexpo(struct zcrypt_device *zdev,
                                   struct ica_rsa_modexpo *mex)
 {
         struct ap_message ap_msg;
-        struct completion work;
+        struct response_type resp_type = {
+                .type = PCIXCC_RESPONSE_TYPE_ICA,
+        };
         int rc;
 
         ap_msg.message = (void *) get_zeroed_page(GFP_KERNEL);
@@ -444,14 +635,14 @@ static long zcrypt_pcixcc_modexpo(struct zcrypt_device *zdev,
                 return -ENOMEM;
         ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
                                 atomic_inc_return(&zcrypt_step);
-        ap_msg.private = &work;
+        ap_msg.private = &resp_type;
         rc = ICAMEX_msg_to_type6MEX_msgX(zdev, &ap_msg, mex);
         if (rc)
                 goto out_free;
-        init_completion(&work);
+        init_completion(&resp_type.work);
         ap_queue_message(zdev->ap_dev, &ap_msg);
         rc = wait_for_completion_interruptible_timeout(
-                                &work, PCIXCC_CLEANUP_TIME);
+                                &resp_type.work, PCIXCC_CLEANUP_TIME);
         if (rc > 0)
                 rc = convert_response_ica(zdev, &ap_msg, mex->outputdata,
                                           mex->outputdatalength);
@@ -478,7 +669,9 @@ static long zcrypt_pcixcc_modexpo_crt(struct zcrypt_device *zdev,
                                       struct ica_rsa_modexpo_crt *crt)
 {
         struct ap_message ap_msg;
-        struct completion work;
+        struct response_type resp_type = {
+                .type = PCIXCC_RESPONSE_TYPE_ICA,
+        };
         int rc;
 
         ap_msg.message = (void *) get_zeroed_page(GFP_KERNEL);
@@ -486,14 +679,14 @@ static long zcrypt_pcixcc_modexpo_crt(struct zcrypt_device *zdev,
                 return -ENOMEM;
         ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
                                 atomic_inc_return(&zcrypt_step);
-        ap_msg.private = &work;
+        ap_msg.private = &resp_type;
         rc = ICACRT_msg_to_type6CRT_msgX(zdev, &ap_msg, crt);
         if (rc)
                 goto out_free;
-        init_completion(&work);
+        init_completion(&resp_type.work);
         ap_queue_message(zdev->ap_dev, &ap_msg);
         rc = wait_for_completion_interruptible_timeout(
-                                &work, PCIXCC_CLEANUP_TIME);
+                                &resp_type.work, PCIXCC_CLEANUP_TIME);
         if (rc > 0)
                 rc = convert_response_ica(zdev, &ap_msg, crt->outputdata,
                                           crt->outputdatalength);
@@ -510,11 +703,55 @@ out_free:
 }
 
 /**
+ * The request distributor calls this function if it picked the PCIXCC/CEX2C
+ * device to handle a send_cprb request.
+ * @zdev: pointer to zcrypt_device structure that identifies the
+ *        PCIXCC/CEX2C device to the request distributor
+ * @xcRB: pointer to the send_cprb request buffer
+ */
+long zcrypt_pcixcc_send_cprb(struct zcrypt_device *zdev, struct ica_xcRB *xcRB)
+{
+        struct ap_message ap_msg;
+        struct response_type resp_type = {
+                .type = PCIXCC_RESPONSE_TYPE_XCRB,
+        };
+        int rc;
+
+        ap_msg.message = (void *) kmalloc(PCIXCC_MAX_XCRB_MESSAGE_SIZE, GFP_KERNEL);
+        if (!ap_msg.message)
+                return -ENOMEM;
+        ap_msg.psmid = (((unsigned long long) current->pid) << 32) +
+                                atomic_inc_return(&zcrypt_step);
+        ap_msg.private = &resp_type;
+        rc = XCRB_msg_to_type6CPRB_msgX(zdev, &ap_msg, xcRB);
+        if (rc)
+                goto out_free;
+        init_completion(&resp_type.work);
+        ap_queue_message(zdev->ap_dev, &ap_msg);
+        rc = wait_for_completion_interruptible_timeout(
+                                &resp_type.work, PCIXCC_CLEANUP_TIME);
+        if (rc > 0)
+                rc = convert_response_xcrb(zdev, &ap_msg, xcRB);
+        else {
+                /* Signal pending or message timed out. */
+                ap_cancel_message(zdev->ap_dev, &ap_msg);
+                if (rc == 0)
+                        /* Message timed out. */
+                        rc = -ETIME;
+        }
+out_free:
+        memset(ap_msg.message, 0x0, ap_msg.length);
+        kfree(ap_msg.message);
+        return rc;
+}
+
+/**
  * The crypto operations for a PCIXCC/CEX2C card.
  */
 static struct zcrypt_ops zcrypt_pcixcc_ops = {
         .rsa_modexpo = zcrypt_pcixcc_modexpo,
         .rsa_modexpo_crt = zcrypt_pcixcc_modexpo_crt,
+        .send_cprb = zcrypt_pcixcc_send_cprb,
 };
 
 /**