Merging upstream version 1.14.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1001 insertions, 0 deletions

diff --git a/nvme-rpmb.c b/nvme-rpmb.c
new file mode 100644
index 0000000..0e11ef3
--- /dev/null
+++ b/nvme-rpmb.c
@@ -0,0 +1,1001 @@
+/*
+ * Copyright (C) 2020 Micron Techology Inc. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version
+ * 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ * nvme-rpmb.c - Implementation of NVMe RPMB support commands in Nvme
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/socket.h>
+#include <linux/if_alg.h>
+#include <linux/socket.h>
+
+#include "nvme.h"
+#include "nvme-print.h"
+#include "nvme-ioctl.h"
+
+#define CREATE_CMD
+
+
+#ifndef AF_ALG
+#define AF_ALG 38
+#endif
+#ifndef SOL_ALG
+#define SOL_ALG 279
+#endif
+
+#define HMAC_SHA256_ALGO_NAME		"hmac(sha256)"
+#define MD5_HASH_ALGO_NAME		"md5"
+#define HMAC_SHA256_HASH_SIZE		32
+#define MD5_HASH_HASH_SIZE		16
+
+extern int nvme_show_id_ctrl_rpmbs(unsigned int);
+/*
+ * Utility function to create hash value of given data (with given key) using
+ * given hash algorithm; this function uses kernel crypto services
+ */
+unsigned char *create_hash(const char *algo,
+			   int hash_size,
+			   unsigned char *data,
+			   int datalen,
+			   unsigned char *key,
+			   int keylen)
+{
+	int error, infd, outfd = -1;
+	unsigned char *hash = NULL;
+	struct sockaddr_alg provider_sa = {
+		.salg_family = AF_ALG,
+		.salg_type = "hash",
+		.salg_name = { 0 }
+	};
+
+	/* copy algorith name */
+	memcpy(provider_sa.salg_name, algo, strlen(algo));
+
+    	/* open netlink socket connection to algorigm provider and bind */
+    	infd = socket(AF_ALG, SOCK_SEQPACKET, 0);
+	if (infd < 0) {
+		perror("socket");
+		return hash;
+	}
+    	error = bind(infd, (struct sockaddr *)&provider_sa, sizeof(provider_sa));
+	if (error < 0) {
+		perror("bind");
+		goto out;
+	}
+
+	/* if algorithm requires key, set it first - empty keys not accepted !*/
+	if (key != NULL && keylen > 0) {
+        	error = setsockopt(infd, SOL_ALG, ALG_SET_KEY, key, keylen);
+		if (error < 0) {
+			perror("setsockopt");
+			goto out;
+		}
+	}
+		
+    	/* now send data to hash */
+    	outfd = accept(infd, NULL, 0);
+	if (outfd < 0) {
+		perror("accept");
+		goto out;
+	}
+    	error = send(outfd, data, datalen, 0);
+	if (error < 0) {
+		perror("send");
+		goto out;
+	}
+
+	/* read computed hash */
+    	hash = (unsigned char *)calloc(hash_size, 1);
+	if (hash == NULL) {
+        	perror("calloc");
+		goto out;
+    	}
+
+    	error = read(outfd, hash, hash_size);
+	if (error != hash_size) {
+        	perror("read");
+        	free(hash);
+        	hash = NULL;
+    	}
+out:
+    if (outfd > 0) close(outfd);
+    if (infd > 0)  close(infd);
+
+    return hash;
+}
+
+/* Function that computes hmac-sha256 hash of given data and key pair. Returns
+ * byte stream (non-null terminated) upon success, NULL otherwise.
+ */
+unsigned char *
+hmac_sha256(unsigned char *data, int datalen, unsigned char *key, int keylen)
+{
+	return create_hash(HMAC_SHA256_ALGO_NAME,
+			   HMAC_SHA256_HASH_SIZE,
+			   data,
+			   datalen,
+			   key,
+			   keylen);
+}
+
+/* Function that computes md5 of given buffer - md5 hash is used as nonce
+ * Returns byte stream (non-null terminated) upon success, NULL otherwise.
+ */
+unsigned char *
+rpmb_md5(unsigned char *data, int datalen)
+{
+	return create_hash(MD5_HASH_ALGO_NAME,
+			   MD5_HASH_HASH_SIZE,
+			   data,
+			   datalen,
+			   NULL,
+			   0);
+}
+
+/* Read data from given file into buffer and return its length */
+static int read_file(const char *file, unsigned char **data, unsigned int *len)
+{
+	struct stat sb;
+	size_t size;
+	unsigned char   *buf = NULL;
+	int fd;
+	int err = -EINVAL;
+
+	if (file == NULL) return err;
+
+	if ((fd = open(file, O_RDONLY)) < 0) {
+		fprintf(stderr, "Failed to open %s: %s\n", file, strerror(errno));
+		return fd;
+	}
+
+	err = fstat(fd, &sb);
+	if (err < 0) {
+		perror("fstat");
+		goto out;
+	}
+
+	size = sb.st_size;
+	if (posix_memalign((void **)&buf, getpagesize(), size)) {
+		fprintf(stderr, "No memory for reading file :%s\n", file);
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = read(fd, buf, size);
+	if (err < 0) {
+		err = -errno;
+		fprintf(stderr, "Failed to read data from file"
+				" %s with %s\n", file, strerror(errno));
+		free(buf);
+		goto out;
+	}
+	err -= size;
+	*data = buf; 
+	*len = size;
+out:
+	close(fd);
+	return err;
+}
+
+/* Write given buffer data to specified file */
+static void write_file(unsigned char *data, size_t len, const char *dir,
+			  const char *file, const char *msg)
+{
+	char temp_folder[PATH_MAX] = { 0 };
+	FILE *fp = NULL;
+
+	if (dir != NULL)
+		sprintf(temp_folder, "%s/%s", dir, file);
+	else
+		sprintf(temp_folder, "./%s", file);
+
+	if ((fp = fopen(temp_folder, "ab+")) != NULL) {
+		if (fwrite(data, 1, len,  fp) != len) {
+			fprintf(stderr, "Failed to write %s data to %s\n",
+				 msg ? msg : "", temp_folder);
+		}
+		fclose(fp);
+	} else  {
+		fprintf(stderr, "Failed to open %s file to write %s\n",
+			temp_folder, msg ? msg : "");
+	}
+}
+
+/* Various definitions used in RPMB related support */
+enum rpmb_request_type {
+	RPMB_REQ_AUTH_KEY_PROGRAM = 0x0001,
+	RPMB_REQ_READ_WRITE_CNTR  = 0x0002,
+	RPMB_REQ_AUTH_DATA_WRITE  = 0x0003,
+	RPMB_REQ_AUTH_DATA_READ   = 0x0004,
+	RPMB_REQ_READ_RESULT      = 0x0005,
+	RPMB_REQ_AUTH_DCB_WRITE   = 0x0006,
+	RPMB_REQ_AUTH_DCB_READ    = 0x0007
+};
+	
+enum rpmb_response_type {
+	RPMB_RSP_AUTH_KEY_PROGRAM = (RPMB_REQ_AUTH_KEY_PROGRAM << 8),
+	RPMB_RSP_READ_WRITE_CNTR  = (RPMB_REQ_READ_WRITE_CNTR  << 8),
+	RPMB_RSP_AUTH_DATA_WRITE  = (RPMB_REQ_AUTH_DATA_WRITE  << 8),
+	RPMB_RSP_AUTH_DATA_READ   = (RPMB_REQ_AUTH_DATA_READ   << 8),
+	RPMB_RSP_READ_RESULT      = (RPMB_REQ_READ_RESULT      << 8),
+	RPMB_RSP_AUTH_DCB_WRITE   = (RPMB_REQ_AUTH_DCB_WRITE   << 8),
+	RPMB_RSP_AUTH_DCB_READ    = (RPMB_REQ_AUTH_DCB_READ    << 8)
+};
+
+/* RPMB data frame structure */
+#pragma pack(1)
+struct rpmb_data_frame_t {
+	unsigned char  pad[191];
+	unsigned char  mac[32];
+	unsigned char  target;     /* 0-6, should match with NSSF with SS, SR */
+	unsigned char  nonce[16];
+	unsigned int   write_counter;
+	unsigned int   address;
+	unsigned int   sectors;
+	unsigned short result;
+	unsigned short type;       /* req or response */
+	unsigned char  data[0];    /* in sector count times */
+};
+#pragma pack()
+	
+struct rpmb_config_block_t {
+	unsigned char  bp_enable;
+	unsigned char  bp_lock;
+	unsigned char  rsvd[510]; 
+};
+
+#define RPMB_DATA_FRAME_SIZE  256
+#define RPMB_NVME_SECP        0xEA 
+#define RPMB_NVME_SPSP        0x0001
+
+#define SEND_RPMB_REQ(tgt, size, req) \
+nvme_sec_send(fd, 0, tgt, RPMB_NVME_SPSP, RPMB_NVME_SECP, size, size, \
+		(unsigned char *)(req))
+	
+#define RECV_RPMB_RSP(tgt, size, rsp) \
+nvme_sec_recv(fd, 0, tgt, RPMB_NVME_SPSP, RPMB_NVME_SECP, size, size, \
+		(unsigned char *)(rsp))
+	
+/* Initialize nonce value in rpmb request frame */
+static void rpmb_nonce_init(struct rpmb_data_frame_t *req)
+{
+	int num = rand();
+	unsigned char *hash = rpmb_md5((unsigned char *)&num, sizeof(num));
+	if (hash) memcpy(req->nonce, hash, sizeof(req->nonce));
+}
+
+/* Read key from a given key buffer or key file */
+static unsigned char *read_rpmb_key(char *keystr, char *keyfile, unsigned int *keysize)
+{
+	unsigned char *keybuf = NULL;
+	
+	if (keystr == NULL) {
+		if (keyfile != NULL)
+			read_file(keyfile, &keybuf, keysize);
+	} else if ((keybuf = (unsigned char *)malloc(strlen(keystr))) != NULL) {
+		*keysize = strlen(keystr);
+		memcpy(keybuf, keystr, *keysize);
+	}
+
+	return keybuf;
+}
+
+/* Initialize RPMB request frame with given values */
+static struct rpmb_data_frame_t *
+rpmb_request_init(unsigned int   req_size,
+		  unsigned short type,
+		  unsigned char  target,
+		  unsigned char  nonce,
+		  unsigned int   addr,
+		  unsigned int   sectors,
+		  unsigned char  *data,
+		  unsigned short data_offset,
+		  unsigned int   data_size)
+{
+	struct rpmb_data_frame_t *req = NULL;
+
+	if ((req = (struct rpmb_data_frame_t *)calloc(req_size, 1)) == NULL) {
+		fprintf(stderr, "Memory allocation failed for request 0x%04x\n",
+			type);
+		return req;
+	}
+
+	req->type = type;
+	req->target = target;
+	req->address = addr;
+	req->sectors = sectors;
+	
+	if (nonce) rpmb_nonce_init(req);
+	if (data)  memcpy((unsigned char *)req + data_offset, data, data_size);
+
+	return req;
+}
+
+/* Process rpmb response and print appropriate error message */
+static int check_rpmb_response( struct rpmb_data_frame_t *req,
+				struct rpmb_data_frame_t *rsp,
+				char *msg)
+{
+	const char *rpmb_result_string [] = {
+		"Operation successful", 
+		"General failure",
+		"Authentication (MAC) failure",
+		"Counter failure (not matching/incrementing failure)",
+		"Address failure (out of range or wrong alignment)",
+		"Write (data/counter/result) failure",
+		"Read (data/counter/result) failure",
+		"Authentication key not yet programmed",
+		"Invalid device configuration block",
+		"Unknown error"
+	};
+	 
+	/* check error status before comparing nonce and mac */
+	if (rsp->result != 0)  {
+		if (rsp->type != ((req->type << 8) & 0xFF00)) {
+			fprintf(stderr, "%s ! non-matching response 0x%04x for"
+				" 0x%04x\n", msg, rsp->type, req->type);
+		} else if ((rsp->result & 0x80) == 0x80) {
+			fprintf(stderr, "%s ! Expired write-counter !\n", msg);
+		} else if (rsp->result) {
+			fprintf(stderr, "%s ! %s\n", msg,
+				rpmb_result_string[rsp->result & 0x7F]);
+		} else if (memcmp(req->nonce, rsp->nonce, 16)) {
+			fprintf(stderr, "%s ! non-matching nonce\n", msg);
+		} else if (memcmp(req->mac, rsp->mac, 32)) {
+			fprintf(stderr, "%s ! non-matching MAC\n", msg);
+		} else if ((req->write_counter + 1) != rsp->write_counter) {
+			fprintf(stderr, "%s ! out-of-sync write-counters\n", msg);
+		}
+	}
+	
+	return (int)(rsp->result);
+}
+
+/* send an initialized rpmb request to the controller and read its response
+ * expected response size give in 'rsp_size'. returns response buffer upon
+ * successful completion (caller must free), NULL otherwise
+ */
+static struct rpmb_data_frame_t *
+rpmb_read_request(int fd, 
+		  struct rpmb_data_frame_t *req,
+	          int req_size,
+	          int rsp_size)
+{
+	struct rpmb_data_frame_t *rsp = NULL;
+	unsigned char msg[1024] = { 0 };
+	int error;
+
+	sprintf((char *)msg, "RPMB request 0x%04x to target 0x%x",
+		req->type, req->target);
+
+	error = SEND_RPMB_REQ(req->target, req_size, req);
+	if (error != 0) {
+		fprintf(stderr, "%s failed with error = 0x%x\n",
+			msg, error);
+		goto error_out;
+	}
+
+	/* read the result back */
+	rsp = (struct rpmb_data_frame_t *)calloc(rsp_size, 1);
+	if (rsp == NULL) {
+		fprintf(stderr, "memory alloc failed for %s\n", msg);
+		goto error_out;
+	}
+
+	/* Read result of previous request */
+	error = RECV_RPMB_RSP(req->target, rsp_size, rsp);
+	if (error) {
+		fprintf(stderr, "error 0x%x receiving response for %s\n",
+			error, msg);
+		goto error_out;
+	}
+
+	/* validate response buffer - match target, nonce, and mac */
+	error = check_rpmb_response(req, rsp, (char *)msg);
+	if (error == 0) return rsp;
+
+error_out:
+	free(rsp);
+	return NULL;
+}
+
+/* read current write counter value from controller */
+static int rpmb_read_write_counter(int fd,
+				   unsigned char target,
+				   unsigned int *counter)
+{
+	int error = -1;
+	int req_size = sizeof(struct rpmb_data_frame_t);
+	struct rpmb_data_frame_t *req = NULL;
+	struct rpmb_data_frame_t *rsp = NULL;
+
+	req = rpmb_request_init(req_size, RPMB_REQ_READ_WRITE_CNTR,
+				target, 1, 0, 0, NULL, 0, 0);
+	if (req == NULL) goto out;
+	if ((rsp = rpmb_read_request(fd, req, req_size, req_size)) == NULL) {
+		goto out;
+	}	
+	*counter = rsp->write_counter; 
+	error = 0;
+	
+out:
+	free(req);
+	free(rsp);
+	return error;
+}
+
+/* Read current device configuration block into specified buffer. It also returns
+ * current write counter value returned as part of response, in case of error it
+ * returns 0
+ */
+static unsigned int rpmb_read_config_block(int fd, unsigned char **config_buf)
+{
+	int req_size = sizeof(struct rpmb_data_frame_t);
+	int cfg_size = sizeof(struct rpmb_config_block_t);
+	int rsp_size = req_size + cfg_size;
+	
+	struct rpmb_data_frame_t   *req = NULL;
+	struct rpmb_data_frame_t   *rsp = NULL;
+	struct rpmb_config_block_t *cfg = NULL;
+	unsigned int retval = 0;
+
+	/* initialize request with nonce, no data on input */
+	req = rpmb_request_init(req_size, RPMB_REQ_AUTH_DCB_READ, 0, 1, 0, 1,
+				0, 0, 0);
+	if ((req == NULL) ||
+	    (rsp = rpmb_read_request(fd, req, req_size, rsp_size)) == NULL)
+	{
+		goto out;
+	}	
+
+	/* copy configuration data to be sent back to caller */
+	cfg = (struct rpmb_config_block_t *)calloc(cfg_size, 1);
+	if (cfg == NULL) {
+		fprintf(stderr, "failed to allocate RPMB config buffer\n");
+		goto out;
+	}
+
+	memcpy(cfg, rsp->data, cfg_size);
+	*config_buf = (unsigned char *)cfg;
+	cfg = NULL;
+	retval = rsp->write_counter;
+out:
+	free(req);
+	free(rsp);
+	free(cfg);
+	return retval;
+}
+
+
+static int rpmb_auth_data_read(int fd, unsigned char target,
+			       unsigned int offset,
+			       unsigned char **msg_buf,
+			       int msg_size, int acc_size)
+{
+	struct rpmb_data_frame_t *req = NULL;
+	struct rpmb_data_frame_t *rsp = NULL;
+	int req_size = sizeof(struct rpmb_data_frame_t);
+	int chunk_size = (acc_size < msg_size) ? acc_size : msg_size;
+	int xfer = chunk_size;
+	unsigned char *bufp = (unsigned char *)malloc(msg_size * 512);
+	unsigned char *tbufp = bufp;
+	int data_size, rsp_size;
+	int error = -1;
+
+	if (bufp == NULL) {
+		fprintf(stderr, "Failed to allocated memory for read-data req\n");
+		goto out;
+	}
+	
+	while (xfer > 0) {
+		rsp_size = req_size + xfer * 512;
+		req = rpmb_request_init(req_size, RPMB_REQ_AUTH_DATA_READ,
+					target, 1, offset, xfer, 0, 0, 0);
+		if (req == NULL) break;
+		if ((rsp = rpmb_read_request(fd, req, req_size, rsp_size)) == NULL)
+		{
+			fprintf(stderr, "read_request failed\n");
+			free(rsp);
+			goto out;
+		}
+
+		data_size = rsp->sectors * 512;
+		memcpy(tbufp, rsp->data, data_size);
+		offset += rsp->sectors;
+		tbufp += data_size;
+		if (offset + chunk_size > msg_size)
+			xfer = msg_size - offset;
+		else 
+			xfer = chunk_size;
+		free(req);
+		free(rsp);
+	}
+	
+	*msg_buf = bufp;
+	error = offset;
+out:
+	return error;
+}
+
+/* Implementation of programming authentication key to given RPMB target */
+static int rpmb_program_auth_key(int fd, unsigned char target,
+				 unsigned char *key_buf, int key_size)
+{
+	int req_size = sizeof(struct rpmb_data_frame_t);
+	int rsp_size = sizeof(struct rpmb_data_frame_t);
+	
+	struct rpmb_data_frame_t *req = NULL;
+	struct rpmb_data_frame_t *rsp = NULL;
+	
+	int err = -ENOMEM;
+	
+	req = rpmb_request_init(req_size, RPMB_REQ_AUTH_KEY_PROGRAM, target,
+				0, 0, 0, key_buf, (223 - key_size), key_size);
+	if (req == NULL) {
+		fprintf(stderr, "failed to allocate request buffer memory\n");
+		goto out;
+	}
+
+	/* send request and read the result first */
+	rsp = rpmb_read_request(fd, req, req_size, rsp_size);
+	if (rsp == NULL || rsp->result != 0) {
+		goto out;
+	}
+
+	/* re-use response buffer */
+	memset(rsp, 0, rsp_size);
+	err = RECV_RPMB_RSP(req->target, rsp_size, (unsigned char *)rsp);
+	if (err != 0) {
+		err = check_rpmb_response(req, rsp, "Failed to Program Key");
+	}
+out:
+	free(req);
+	free(rsp);
+	
+	return err;
+}
+
+
+/* Implementation of RPMB authenticated data write command; this function
+ * transfers msg_size bytes from msg_buf to controller 'addr'. Returns
+ * number of bytes actually written to, otherwise negetive error code
+ * on failures.
+ */
+static int auth_data_write_chunk(int fd, unsigned char tgt, unsigned int addr,
+				 unsigned char *msg_buf, int msg_size,
+				 unsigned char *keybuf, int keysize)
+{
+	int req_size = sizeof(struct rpmb_data_frame_t) + msg_size;
+	int rsp_size = sizeof(struct rpmb_data_frame_t);
+	
+	struct rpmb_data_frame_t *req = NULL;
+	struct rpmb_data_frame_t *rsp = NULL;
+	
+	unsigned int write_cntr = 0;
+	unsigned char *mac = NULL;
+	int error  = -ENOMEM;
+
+	/* get current write counter and copy to the request  */
+	error = rpmb_read_write_counter(fd, tgt, &write_cntr);
+	if (error != 0) {
+	   fprintf(stderr, "Failed to read write counter for write-data\n");
+	    goto out;
+	}
+	
+	req = rpmb_request_init(req_size, RPMB_REQ_AUTH_DATA_WRITE, tgt, 0,
+				addr, (msg_size / 512), msg_buf,
+				offsetof(struct rpmb_data_frame_t, data), msg_size);
+	if (req == NULL) {
+		fprintf(stderr, "Memory alloc failed for write-data command\n");
+		goto out;
+	}
+
+	req->write_counter = write_cntr;
+
+	/* compute HMAC hash */
+	mac = hmac_sha256(((unsigned char *)req + 223), req_size - 223,
+			   keybuf, keysize);
+	if (mac == NULL) {
+		fprintf(stderr, "failed to compute HMAC-SHA256\n");
+		error = -1;
+		goto out;
+	}
+
+	memcpy(req->mac, mac, 32);
+	
+	/* send the request and get response */
+	error = SEND_RPMB_REQ(tgt, req_size, (unsigned char *)req);
+	if (error != 0) {
+	    fprintf(stderr, "RPMB request 0x%04x for 0x%x, error: %d\n",
+		    req->type, tgt, error);
+	    goto out;
+	}
+	
+	/* send the request to get the result and then request to get the response */
+        rsp = (struct rpmb_data_frame_t *)calloc(rsp_size, 1);
+	rsp->target = req->target;
+	rsp->type = RPMB_REQ_READ_RESULT;
+	error = SEND_RPMB_REQ(tgt, rsp_size, (unsigned char *)rsp);
+	if (error != 0 || rsp->result != 0) {
+		fprintf(stderr, "Write-data read result 0x%x, error = 0x%x\n",
+			rsp->result, error);
+		goto out;
+	}
+
+	/* Read final response */
+	memset(rsp, 0, rsp_size);
+	error = RECV_RPMB_RSP(tgt, rsp_size, (unsigned char *)rsp);
+	if (error != 0)
+		fprintf(stderr, "Auth data write recv error = 0x%x\n", error);
+	else 
+    		error = check_rpmb_response(req, rsp, "Failed to write-data");
+out:
+	free(req);
+	free(rsp);
+	free(mac);
+
+	return error;
+}
+
+/* send the request and get response */
+static int rpmb_auth_data_write(int fd, unsigned char target,
+				unsigned int addr, int acc_size,
+				unsigned char *msg_buf, int msg_size,
+				unsigned char *keybuf, int keysize)
+{
+	int chunk_size = acc_size < msg_size ? acc_size : msg_size;
+	int xfer   = chunk_size;
+	int offset = 0;
+
+	while (xfer > 0 ) {
+		if (auth_data_write_chunk(fd, target, (addr + offset / 512),
+				          msg_buf + offset, xfer,
+				          keybuf, keysize) != 0)
+		{
+			/* error writing chunk data */
+			break;	
+		}
+
+		offset += xfer;
+		if (offset + chunk_size > msg_size)
+			xfer = msg_size - offset;
+		else 
+			xfer = chunk_size;
+	}
+
+	return offset;
+}
+
+/* writes given config_block buffer to the drive target 0 */
+static int rpmb_write_config_block(int fd, unsigned char *cfg_buf,
+				   unsigned char *keybuf, int keysize)
+{
+	int cfg_size = sizeof(struct rpmb_config_block_t);
+	int rsp_size = sizeof(struct rpmb_data_frame_t);
+	int req_size = rsp_size + cfg_size;
+	
+	struct rpmb_data_frame_t *req = NULL;
+	struct rpmb_data_frame_t *rsp = NULL;
+	unsigned char *cfg_buf_read = NULL, *mac = NULL;
+	unsigned int write_cntr = 0;
+	int   error = -ENOMEM;
+	
+	/* initialize request */
+	req = rpmb_request_init(req_size, RPMB_REQ_AUTH_DCB_WRITE, 0, 0, 0, 1,
+				cfg_buf, offsetof(struct rpmb_data_frame_t, data),
+				cfg_size);
+	if (req == NULL) {
+		fprintf(stderr, "failed to allocate rpmb request buffer\n");
+		goto out; 
+	}
+
+	/* read config block write_counter from controller */
+	write_cntr = rpmb_read_config_block(fd, &cfg_buf_read);
+	if (cfg_buf_read == NULL) {
+	    	fprintf(stderr, "failed to read config block write counter\n");
+		error = -EIO;
+	    	goto out;
+	}
+
+	free(cfg_buf_read);
+	req->write_counter = write_cntr;
+	mac = hmac_sha256(((unsigned char *)req + 223), req_size - 223,
+			   keybuf, keysize);
+	if (mac == NULL) {
+		fprintf(stderr, "failed to compute hmac-sha256 hash\n");
+		error = -EINVAL;
+	    	goto out;
+	}
+	
+	memcpy(req->mac, mac, sizeof(req->mac)); 
+	
+	error = SEND_RPMB_REQ(0, req_size, (unsigned char *)req);
+	if (error != 0) {
+		fprintf(stderr, "Write-config RPMB request, error = 0x%x\n",
+			error);
+		goto out;
+	}
+	
+	/* get response */
+	rsp = (struct rpmb_data_frame_t *)calloc(rsp_size, 1);
+	if (rsp == NULL) {
+		fprintf(stderr, "failed to allocate response buffer memory\n");
+		error = -ENOMEM;
+		goto out;
+	}
+
+	/* get result first */
+	memset(rsp, 0, rsp_size);
+	rsp->target = req->target;
+	rsp->type = RPMB_REQ_READ_RESULT;
+	/* get the response and validate */
+	error = RECV_RPMB_RSP(req->target, rsp_size, rsp);
+	if (error != 0) {
+		fprintf(stderr,"Failed getting write-config response\
+			error = 0x%x\n", error);
+		goto out;
+	}
+	error = check_rpmb_response(req, rsp,
+				  "Failed to retrieve write-config response");
+out:
+	free(req);
+	free(rsp);
+	free(mac);
+	
+	return error;
+}
+
+static bool invalid_xfer_size(int blocks, unsigned int bpsz)
+{
+	return ((blocks <= 0) || 
+		(blocks * 512) > ((bpsz + 1) * 128 * 1024));
+}
+
+/* Handling rpmb sub-command */
+int rpmb_cmd_option(int argc, char **argv, struct command *cmd, struct plugin *plugin)
+{
+	const char *desc    = "Run RPMB command on the supporting controller";
+	const char *msg     = "data to be written on write-data or write-config commands";
+	const char *mfile   = "data file for read/write-data, read/write-config options";
+	const char *kfile   = "key file that has authentication key to be used";
+	const char *target  = "RPMB target - numerical value of 0 to 6, default 0";
+	const char *address = "Sector offset to read from or write to for an RPMB target, default 0";
+	const char *blocks  = "Number of 512 blocks to read or write";
+	const char *key     = "key to be used for authentication";
+	const char *opt     = "RPMB action - info, program-key, read-counter, write-data, " \
+			      "read-data, write-config and read-config";
+	
+	struct config {
+		char *cmd;
+		char *key;
+		char *msg;
+		char *keyfile;
+		char *msgfile;
+		int  opt;
+		int  address;
+		int  blocks; 
+		char target;
+	};
+	
+	struct config cfg = {
+		.cmd     = "info",
+		.key     = NULL,
+		.msg     = NULL,
+		.msgfile = NULL,
+		.keyfile = NULL,
+		.opt     = 0,
+		.address = 0,
+		.blocks  = 0,
+		.target  = 0,
+	};
+	
+	OPT_ARGS(opts) = {
+		OPT_STRING("cmd",     'c', "command", &cfg.cmd,     opt),
+		OPT_STRING("msgfile", 'f', "FILE",    &cfg.msgfile, mfile),
+		OPT_STRING("keyfile", 'g', "FILE",    &cfg.keyfile, kfile),
+		OPT_STRING("key",     'k', "key",     &cfg.key,     key),
+		OPT_STRING("msg",     'd', "data",    &cfg.msg,     msg),
+		OPT_UINT("address",   'o', &cfg.address,  address),
+		OPT_UINT("blocks",    'b', &cfg.blocks,   blocks),
+		OPT_UINT("target",    't', &cfg.target,   target),
+		OPT_END()
+	};
+	
+	unsigned int write_cntr = 0;
+	unsigned char *key_buf = NULL;
+	unsigned char *msg_buf = NULL;
+	unsigned int msg_size = 0;
+	unsigned int key_size = 0;
+	int fd = -1, err = -1;
+	struct nvme_id_ctrl ctrl;
+
+	union ctrl_rpmbs_reg {
+		struct {
+			unsigned int num_targets:3;
+			unsigned int auth_method:3;
+			unsigned int reserved:10;
+			unsigned int total_size:8;   /* 128K units */
+			unsigned int access_size:8;  /* in 512 byte count */
+		};
+		unsigned int rpmbs;
+	} regs;
+	
+	if ((fd = parse_and_open(argc, argv, desc, opts)) < 0)
+		goto out;
+	
+	/* before parsing  commands, check if controller supports any RPMB targets */
+	err = nvme_identify_ctrl(fd, &ctrl);
+	if (err)
+		goto out;
+	
+	regs.rpmbs = le32_to_cpu(ctrl.rpmbs);
+	if (regs.num_targets == 0) {
+		fprintf(stderr, "No RPMB targets are supported by the drive\n");
+		goto out;
+	}
+	
+	/* parse and validate options; default print rpmb support info */
+	if (cfg.cmd == 0 || strcmp(cfg.cmd, "info") == 0) {
+		nvme_show_id_ctrl_rpmbs(regs.rpmbs);
+		goto out;
+	}
+	
+	if (strcmp(cfg.cmd, "program-key") == 0)
+		cfg.opt = RPMB_REQ_AUTH_KEY_PROGRAM;
+	else if (strcmp(cfg.cmd, "read-counter") == 0)
+		cfg.opt = RPMB_REQ_READ_WRITE_CNTR;
+	else if (strcmp(cfg.cmd, "write-data") == 0)
+		cfg.opt = RPMB_REQ_AUTH_DATA_WRITE;
+	else if (strcmp(cfg.cmd, "read-data") == 0)
+		cfg.opt = RPMB_REQ_AUTH_DATA_READ;
+	else if (strcmp(cfg.cmd, "write-config") == 0)
+		cfg.opt = RPMB_REQ_AUTH_DCB_WRITE;
+	else if (strcmp(cfg.cmd, "read-config") == 0)
+		cfg.opt = RPMB_REQ_AUTH_DCB_READ;
+	else {
+		fprintf(stderr, "Invalid option %s for rpmb command\n", cfg.cmd);
+		goto out;
+	}
+	
+	/* input file/data processing */
+	if (cfg.opt == RPMB_REQ_AUTH_DCB_WRITE || 
+	    cfg.opt == RPMB_REQ_AUTH_DATA_WRITE ||
+	    cfg.opt == RPMB_REQ_AUTH_KEY_PROGRAM)
+	{
+		key_buf = read_rpmb_key(cfg.key, cfg.keyfile, &key_size);
+		if (key_buf == NULL) {
+			fprintf(stderr, "Failed to read key\n");
+			goto out;
+		}
+	
+		if (key_size > 223 || key_size <= 0) {
+			fprintf(stderr, "Invalid key size %d, valid input 1 to 223\n",
+			key_size);
+			goto out;
+		}
+
+		if (cfg.opt == RPMB_REQ_AUTH_DCB_WRITE ||
+		    cfg.opt == RPMB_REQ_AUTH_DATA_WRITE) {
+			if (cfg.msg != NULL) {
+				msg_size = strlen(cfg.msg);
+				msg_buf = (unsigned char *)malloc(msg_size);
+				memcpy(msg_buf, cfg.msg, msg_size);
+			} else {
+				err = read_file(cfg.msgfile, &msg_buf, &msg_size);
+				if (err || msg_size <= 0) {
+					fprintf(stderr, "Failed to read file %s\n",
+						cfg.msgfile);
+					goto out;
+				}
+			}
+		}
+	}
+	
+	switch (cfg.opt) {
+		case RPMB_REQ_READ_WRITE_CNTR:
+			err = rpmb_read_write_counter(fd, cfg.target, &write_cntr);
+			if (err == 0)
+				printf("Write Counter is: %u\n", write_cntr);
+			break;
+	
+		case RPMB_REQ_AUTH_DCB_READ:
+			write_cntr = rpmb_read_config_block(fd, &msg_buf);
+			if (msg_buf == NULL) {
+				fprintf(stderr, "failed read config blk\n");
+				goto out;
+			}
+
+			/* no output file is given, print the data on stdout */
+			if (cfg.msgfile == 0) {
+				struct rpmb_config_block_t *cfg =
+						(struct rpmb_config_block_t *)msg_buf;
+				printf("Boot Parition Protection is %s\n",
+					((cfg->bp_enable & 0x1)  ? "Enabled" : "Disabled"));
+				printf("Boot Parition 1 is %s\n",
+					((cfg->bp_lock & 0x2) ? "Locked" : "Unlocked"));
+				printf("Boot Parition 0 is %s\n",
+					((cfg->bp_lock & 0x1) ? "Locked" : "Unlocked"));
+			} else {
+				printf("Saving received config data to %s file\n", cfg.msgfile);
+				write_file(msg_buf, sizeof(struct rpmb_config_block_t), NULL,
+					   cfg.msgfile, NULL);
+			}
+			err = (write_cntr == 0);
+			break;
+	
+		case RPMB_REQ_AUTH_DATA_READ:
+			/* check if requested data is beyond what target supports */
+			msg_size = cfg.blocks * 512;
+			if (invalid_xfer_size(cfg.blocks, regs.total_size)) {
+				fprintf(stderr, "invalid transfer size %d \n",
+					msg_size);
+				break;
+			}
+			err = rpmb_auth_data_read(fd, cfg.target, cfg.address,
+						  &msg_buf, cfg.blocks,
+						  (regs.access_size + 1));
+			if (err > 0 && msg_buf != NULL) {
+				printf("Writting %d bytes to file %s\n",
+					err * 512, cfg.msgfile);
+				write_file(msg_buf, err * 512, NULL,
+					   cfg.msgfile, NULL);
+			}
+			break;
+	
+		case RPMB_REQ_AUTH_DATA_WRITE:
+			if (invalid_xfer_size(cfg.blocks, regs.total_size) || 
+			    (cfg.blocks * 512) > msg_size) {
+				fprintf(stderr, "invalid transfer size %d\n", 
+					cfg.blocks * 512);
+				break;
+			} else if ((cfg.blocks * 512) < msg_size) {
+				msg_size = cfg.blocks * 512;
+			}
+			err = rpmb_auth_data_write(fd, cfg.target, cfg.address,
+						  ((regs.access_size + 1) * 512),
+						   msg_buf, msg_size,
+						   key_buf, key_size);
+
+			/* print whatever extent of data written to target */
+			printf("Written %d sectors out of %d @target(%d):0x%x\n",
+				err/512, msg_size/512, cfg.target, cfg.address);
+			break;
+
+		case RPMB_REQ_AUTH_DCB_WRITE:
+			err = rpmb_write_config_block(fd, msg_buf, key_buf, key_size);
+			break;
+	
+		case RPMB_REQ_AUTH_KEY_PROGRAM:
+			err = rpmb_program_auth_key(fd, cfg.target, key_buf, key_size);
+			break;
+		default:
+			break;
+	}
+	 
+out:
+	/* release memory  */
+	free(key_buf);
+	free(msg_buf);
+	
+	/* close file descriptor */
+	if (fd > 0) close(fd);
+	
+	return err;
+}