cmd/mbr.c - filogic/uboot - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * cmd_mbr.c -- MBR (Master Boot Record) handling command
  *
  * Copyright (C) 2020 Samsung Electronics
  * author: Marek Szyprowski <m.szyprowski@samsung.com>
  *
  * based on the gpt command.
  */

 #include <blk.h>
 #include <command.h>
 #include <malloc.h>
 #include <part.h>
 #include <vsprintf.h>

 /**
  * extract_val() - Extract a value from the key=value pair list
  * @str: pointer to string with key=values pairs
  * @key: pointer to the key to search for
  *
  * The list of parameters is come separated, only a value for
  * the given key is returend.
  *
  * Function allocates memory for the value, remember to free!
  *
  * Return: Pointer to allocated string with the value.
  */
 static char *extract_val(const char *str, const char *key)
 {
 	char *v, *k;
 	char *s, *strcopy;
 	char *new = NULL;

 	strcopy = strdup(str);
 	if (strcopy == NULL)
 		return NULL;

 	s = strcopy;
 	while (s) {
 		v = strsep(&s, ",");
 		if (!v)
 			break;
 		k = strsep(&v, "=");
 		if (!k)
 			break;
 		if  (strcmp(k, key) == 0) {
 			new = strdup(v);
 			break;
 		}
 	}

 	free(strcopy);

 	return new;
 }

 /**
  * found_key() - Search for a key without a value in the parameter list
  * @str: pointer to string with key
  * @key: pointer to the key to search for
  *
  * The list of parameters is come separated.
  *
  * Return: True if key has been found.
  */
 static bool found_key(const char *str, const char *key)
 {
 	char *k;
 	char *s, *strcopy;
 	bool result = false;

 	strcopy = strdup(str);
 	if (!strcopy)
 		return NULL;

 	s = strcopy;
 	while (s) {
 		k = strsep(&s, ",");
 		if (!k)
 			break;
 		if  (strcmp(k, key) == 0) {
 			result = true;
 			break;
 		}
 	}

 	free(strcopy);

 	return result;
 }

 static int str_to_partitions(const char *str_part, int blksz,
 	unsigned long *disk_uuid, struct disk_partition **partitions,
 	int *parts_count)
 {
 	char *tok, *str, *s;
 	int i;
 	char *val, *p;
 	int p_count;
 	struct disk_partition *parts;
 	int errno = 0;
 	uint64_t size_ll, start_ll;

 	if (str_part == NULL)
 		return -1;

 	str = strdup(str_part);
 	if (str == NULL)
 		return -ENOMEM;

 	/* extract disk guid */
 	s = str;
 	val = extract_val(str, "uuid_disk");
 	if (val) {
 		val = strsep(&val, ";");
 		p = val;
 		*disk_uuid = ustrtoull(p, &p, 0);
 		free(val);
 		/* Move s to first partition */
 		strsep(&s, ";");
 	}
 	if (s == NULL) {
 		printf("Error: is the partitions string NULL-terminated?\n");
 		return -EINVAL;
 	}

 	/* remove the optional semicolon at the end of the string */
 	i = strlen(s) - 1;
 	if (s[i] == ';')
 		s[i] = '\0';

 	/* calculate expected number of partitions */
 	p_count = 1;
 	p = s;
 	while (*p) {
 		if (*p++ == ';')
 			p_count++;
 	}

 	/* allocate memory for partitions */
 	parts = calloc(sizeof(struct disk_partition), p_count);
 	if (parts == NULL)
 		return -ENOMEM;

 	/* retrieve partitions data from string */
 	for (i = 0; i < p_count; i++) {
 		tok = strsep(&s, ";");

 		if (tok == NULL)
 			break;

 		/* size */
 		val = extract_val(tok, "size");
 		if (!val) { /* 'size' is mandatory */
 			errno = -4;
 			goto err;
 		}
 		p = val;
 		if ((strcmp(p, "-") == 0)) {
 			/* auto extend the size */
 			parts[i].size = 0;
 		} else {
 			size_ll = ustrtoull(p, &p, 0);
 			parts[i].size = size_ll / blksz;
 		}
 		free(val);

 		/* start address */
 		val = extract_val(tok, "start");
 		if (val) { /* start address is optional */
 			p = val;
 			start_ll = ustrtoull(p, &p, 0);
 			parts[i].start = start_ll / blksz;
 			free(val);
 		}

 		/* system id */
 		val = extract_val(tok, "id");
 		if (!val) { /* '' is mandatory */
 			errno = -4;
 			goto err;
 		}
 		p = val;
 		parts[i].sys_ind = ustrtoul(p, &p, 0);
 		free(val);

 		/* bootable */
 		if (found_key(tok, "bootable"))
 			parts[i].bootable = PART_BOOTABLE;
 	}

 	*parts_count = p_count;
 	*partitions = parts;
 	free(str);

 	return 0;
 err:
 	free(str);
 	free(parts);

 	return errno;
 }

 static int do_write_mbr(struct blk_desc *dev, const char *str)
 {
 	unsigned long disk_uuid = 0;
 	struct disk_partition *partitions;
 	int blksz = dev->blksz;
 	int count;

 	if (str_to_partitions(str, blksz, &disk_uuid, &partitions, &count)) {
 		printf("MBR: failed to setup partitions from \"%s\"\n", str);
 		return -1;
 	}

 	if (layout_mbr_partitions(partitions, count, dev->lba)) {
 		printf("MBR: failed to layout partitions on the device\n");
 		free(partitions);
 		return -1;
 	}

 	if (write_mbr_partitions(dev, partitions, count, disk_uuid)) {
 		printf("MBR: failed to write partitions to the device\n");
 		free(partitions);
 		return -1;
 	}

 	return 0;
 }

 static int do_verify_mbr(struct blk_desc *dev, const char *str)
 {
 	unsigned long disk_uuid = 0;
 	struct disk_partition *partitions;
 	int blksz = dev->blksz;
 	int count, i, ret = 1;

 	if (str_to_partitions(str, blksz, &disk_uuid, &partitions, &count)) {
 		printf("MBR: failed to setup partitions from \"%s\"\n", str);
 		return -1;
 	}

 	for (i = 0; i < count; i++) {
 		struct disk_partition p;

 		if (part_get_info_by_type(dev, i + 1, PART_TYPE_DOS, &p))
 			goto fail;

 		if ((partitions[i].size && p.size != partitions[i].size) ||
 		    (partitions[i].start && p.start != partitions[i].start) ||
 		    p.sys_ind != partitions[i].sys_ind)
 			goto fail;
 	}
 	ret = 0;
 fail:
 	free(partitions);
 	return ret;
 }

 static int do_mbr(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
 {
 	const char *parts = NULL;
 	int ret = CMD_RET_SUCCESS;
 	int dev = 0;
 	char *ep;
 	struct blk_desc *blk_dev_desc = NULL;

 	if (argc != 4 && argc != 5)
 		return CMD_RET_USAGE;

 	dev = (int)dectoul(argv[3], &ep);
 	if (!ep || ep[0] != '\0') {
 		printf("'%s' is not a number\n", argv[3]);
 		return CMD_RET_USAGE;
 	}
 	blk_dev_desc = blk_get_dev(argv[2], dev);
 	if (!blk_dev_desc) {
 		printf("%s: %s dev %d NOT available\n",
 		       __func__, argv[2], dev);
 		return CMD_RET_FAILURE;
 	}

 	if ((strcmp(argv[1], "write") == 0)) {
 		parts = (argc == 5) ? argv[4] : env_get("mbr_parts");
 		printf("MBR: write ");
 		ret = do_write_mbr(blk_dev_desc, parts);
 	} else if ((strcmp(argv[1], "verify") == 0)) {
 		printf("MBR: verify ");
 		parts = (argc == 5) ? argv[4] : env_get("mbr_parts");
 		ret = do_verify_mbr(blk_dev_desc, parts);
 	} else {
 		return CMD_RET_USAGE;
 	}

 	if (ret) {
 		printf("error!\n");
 		return CMD_RET_FAILURE;
 	}

 	printf("success!\n");
 	return CMD_RET_SUCCESS;
 }

 U_BOOT_CMD(mbr, CONFIG_SYS_MAXARGS, 1, do_mbr,
 	"MBR (Master Boot Record)",
 	"<command> <interface> <dev> <partitions_list>\n"
 	" - MBR partition table restoration utility\n"
 	" Restore or check partition information on a device connected\n"
 	" to the given block interface\n"
 	" Example usage:\n"
 	" mbr write mmc 0 [\"${mbr_parts}\"]\n"
 	" mbr verify mmc 0 [\"${partitions}\"]\n"
 );
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* cmd_mbr.c -- MBR (Master Boot Record) handling command
	*
	* Copyright (C) 2020 Samsung Electronics
	* author: Marek Szyprowski <m.szyprowski@samsung.com>
	*
	* based on the gpt command.
	*/

	#include <blk.h>
	#include <command.h>
	#include <malloc.h>
	#include <part.h>
	#include <vsprintf.h>

	/**
	* extract_val() - Extract a value from the key=value pair list
	* @str: pointer to string with key=values pairs
	* @key: pointer to the key to search for
	*
	* The list of parameters is come separated, only a value for
	* the given key is returend.
	*
	* Function allocates memory for the value, remember to free!
	*
	* Return: Pointer to allocated string with the value.
	*/
	static char extract_val(const char str, const char *key)
	{
	char v, k;
	char s, strcopy;
	char *new = NULL;

	strcopy = strdup(str);
	if (strcopy == NULL)
	return NULL;

	s = strcopy;
	while (s) {
	v = strsep(&s, ",");
	if (!v)
	break;
	k = strsep(&v, "=");
	if (!k)
	break;
	if (strcmp(k, key) == 0) {
	new = strdup(v);
	break;
	}
	}

	free(strcopy);

	return new;
	}

	/**
	* found_key() - Search for a key without a value in the parameter list
	* @str: pointer to string with key
	* @key: pointer to the key to search for
	*
	* The list of parameters is come separated.
	*
	* Return: True if key has been found.
	*/
	static bool found_key(const char str, const char key)
	{
	char *k;
	char s, strcopy;
	bool result = false;

	strcopy = strdup(str);
	if (!strcopy)
	return NULL;

	s = strcopy;
	while (s) {
	k = strsep(&s, ",");
	if (!k)
	break;
	if (strcmp(k, key) == 0) {
	result = true;
	break;
	}
	}

	free(strcopy);

	return result;
	}

	static int str_to_partitions(const char *str_part, int blksz,
	unsigned long disk_uuid, struct disk_partition *partitions,
	int *parts_count)
	{
	char tok, str, *s;
	int i;
	char val, p;
	int p_count;
	struct disk_partition *parts;
	int errno = 0;
	uint64_t size_ll, start_ll;

	if (str_part == NULL)
	return -1;

	str = strdup(str_part);
	if (str == NULL)
	return -ENOMEM;

	/* extract disk guid */
	s = str;
	val = extract_val(str, "uuid_disk");
	if (val) {
	val = strsep(&val, ";");
	p = val;
	*disk_uuid = ustrtoull(p, &p, 0);
	free(val);
	/* Move s to first partition */
	strsep(&s, ";");
	}
	if (s == NULL) {
	printf("Error: is the partitions string NULL-terminated?\n");
	return -EINVAL;
	}

	/* remove the optional semicolon at the end of the string */
	i = strlen(s) - 1;
	if (s[i] == ';')
	s[i] = '\0';

	/* calculate expected number of partitions */
	p_count = 1;
	p = s;
	while (*p) {
	if (*p++ == ';')
	p_count++;
	}

	/* allocate memory for partitions */
	parts = calloc(sizeof(struct disk_partition), p_count);
	if (parts == NULL)
	return -ENOMEM;

	/* retrieve partitions data from string */
	for (i = 0; i < p_count; i++) {
	tok = strsep(&s, ";");

	if (tok == NULL)
	break;

	/* size */
	val = extract_val(tok, "size");
	if (!val) { /* 'size' is mandatory */
	errno = -4;
	goto err;
	}
	p = val;
	if ((strcmp(p, "-") == 0)) {
	/* auto extend the size */
	parts[i].size = 0;
	} else {
	size_ll = ustrtoull(p, &p, 0);
	parts[i].size = size_ll / blksz;
	}
	free(val);

	/* start address */
	val = extract_val(tok, "start");
	if (val) { /* start address is optional */
	p = val;
	start_ll = ustrtoull(p, &p, 0);
	parts[i].start = start_ll / blksz;
	free(val);
	}

	/* system id */
	val = extract_val(tok, "id");
	if (!val) { /* '' is mandatory */
	errno = -4;
	goto err;
	}
	p = val;
	parts[i].sys_ind = ustrtoul(p, &p, 0);
	free(val);

	/* bootable */
	if (found_key(tok, "bootable"))
	parts[i].bootable = PART_BOOTABLE;
	}

	*parts_count = p_count;
	*partitions = parts;
	free(str);

	return 0;
	err:
	free(str);
	free(parts);

	return errno;
	}

	static int do_write_mbr(struct blk_desc dev, const char str)
	{
	unsigned long disk_uuid = 0;
	struct disk_partition *partitions;
	int blksz = dev->blksz;
	int count;

	if (str_to_partitions(str, blksz, &disk_uuid, &partitions, &count)) {
	printf("MBR: failed to setup partitions from \"%s\"\n", str);
	return -1;
	}

	if (layout_mbr_partitions(partitions, count, dev->lba)) {
	printf("MBR: failed to layout partitions on the device\n");
	free(partitions);
	return -1;
	}

	if (write_mbr_partitions(dev, partitions, count, disk_uuid)) {
	printf("MBR: failed to write partitions to the device\n");
	free(partitions);
	return -1;
	}

	return 0;
	}

	static int do_verify_mbr(struct blk_desc dev, const char str)
	{
	unsigned long disk_uuid = 0;
	struct disk_partition *partitions;
	int blksz = dev->blksz;
	int count, i, ret = 1;

	if (str_to_partitions(str, blksz, &disk_uuid, &partitions, &count)) {
	printf("MBR: failed to setup partitions from \"%s\"\n", str);
	return -1;
	}

	for (i = 0; i < count; i++) {
	struct disk_partition p;

	if (part_get_info_by_type(dev, i + 1, PART_TYPE_DOS, &p))
	goto fail;

	if ((partitions[i].size && p.size != partitions[i].size) \|\|
	(partitions[i].start && p.start != partitions[i].start) \|\|
	p.sys_ind != partitions[i].sys_ind)
	goto fail;
	}
	ret = 0;
	fail:
	free(partitions);
	return ret;
	}

	static int do_mbr(struct cmd_tbl cmdtp, int flag, int argc, char const argv[])
	{
	const char *parts = NULL;
	int ret = CMD_RET_SUCCESS;
	int dev = 0;
	char *ep;
	struct blk_desc *blk_dev_desc = NULL;

	if (argc != 4 && argc != 5)
	return CMD_RET_USAGE;

	dev = (int)dectoul(argv[3], &ep);
	if (!ep \|\| ep[0] != '\0') {
	printf("'%s' is not a number\n", argv[3]);
	return CMD_RET_USAGE;
	}
	blk_dev_desc = blk_get_dev(argv[2], dev);
	if (!blk_dev_desc) {
	printf("%s: %s dev %d NOT available\n",
	__func__, argv[2], dev);
	return CMD_RET_FAILURE;
	}

	if ((strcmp(argv[1], "write") == 0)) {
	parts = (argc == 5) ? argv[4] : env_get("mbr_parts");
	printf("MBR: write ");
	ret = do_write_mbr(blk_dev_desc, parts);
	} else if ((strcmp(argv[1], "verify") == 0)) {
	printf("MBR: verify ");
	parts = (argc == 5) ? argv[4] : env_get("mbr_parts");
	ret = do_verify_mbr(blk_dev_desc, parts);
	} else {
	return CMD_RET_USAGE;
	}

	if (ret) {
	printf("error!\n");
	return CMD_RET_FAILURE;
	}

	printf("success!\n");
	return CMD_RET_SUCCESS;
	}

	U_BOOT_CMD(mbr, CONFIG_SYS_MAXARGS, 1, do_mbr,
	"MBR (Master Boot Record)",
	"<command> <interface> <dev> <partitions_list>\n"
	" - MBR partition table restoration utility\n"
	" Restore or check partition information on a device connected\n"
	" to the given block interface\n"
	" Example usage:\n"
	" mbr write mmc 0 [\"${mbr_parts}\"]\n"
	" mbr verify mmc 0 [\"${partitions}\"]\n"
	);