577 lines
14 KiB
C
577 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
|
|
/*
|
|
* dm-init.c
|
|
* Copyright (C) 2017 The Chromium OS Authors <chromium-os-dev@chromium.org>
|
|
*
|
|
* This file is released under the GPLv2.
|
|
*/
|
|
|
|
#include <linux/ctype.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/device.h>
|
|
#include <linux/device-mapper.h>
|
|
#include <linux/init.h>
|
|
#include <linux/list.h>
|
|
#include <linux/moduleparam.h>
|
|
|
|
#define DM_MSG_PREFIX "init"
|
|
#define DM_MAX_DEVICES 256
|
|
#define DM_MAX_TARGETS 256
|
|
#define DM_MAX_STR_SIZE 4096
|
|
#define DM_MAX_WAITFOR 256
|
|
|
|
static char *create;
|
|
|
|
static char *waitfor[DM_MAX_WAITFOR];
|
|
|
|
/*
|
|
* Format: dm-mod.create=<name>,<uuid>,<minor>,<flags>,<table>[,<table>+][;<name>,<uuid>,<minor>,<flags>,<table>[,<table>+]+]
|
|
* Table format: <start_sector> <num_sectors> <target_type> <target_args>
|
|
* Block devices to wait for to become available before setting up tables:
|
|
* dm-mod.waitfor=<device1>[,..,<deviceN>]
|
|
*
|
|
* See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..." format
|
|
* details.
|
|
*/
|
|
|
|
struct dm_device {
|
|
struct dm_ioctl dmi;
|
|
struct dm_target_spec *table[DM_MAX_TARGETS];
|
|
char *target_args_array[DM_MAX_TARGETS];
|
|
struct list_head list;
|
|
};
|
|
|
|
static const char * const dm_allowed_targets[] __initconst = {
|
|
"crypt",
|
|
"delay",
|
|
"linear",
|
|
"snapshot-origin",
|
|
"striped",
|
|
"verity",
|
|
};
|
|
|
|
static int __init dm_verify_target_type(const char *target)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(dm_allowed_targets); i++) {
|
|
if (!strcmp(dm_allowed_targets[i], target))
|
|
return 0;
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
static void __init dm_setup_cleanup(struct list_head *devices)
|
|
{
|
|
struct dm_device *dev, *tmp;
|
|
unsigned int i;
|
|
|
|
list_for_each_entry_safe(dev, tmp, devices, list) {
|
|
list_del(&dev->list);
|
|
for (i = 0; i < dev->dmi.target_count; i++) {
|
|
kfree(dev->table[i]);
|
|
kfree(dev->target_args_array[i]);
|
|
}
|
|
kfree(dev);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* str_field_delimit - delimit a string based on a separator char.
|
|
* @str: the pointer to the string to delimit.
|
|
* @separator: char that delimits the field
|
|
*
|
|
* Find a @separator and replace it by '\0'.
|
|
* Remove leading and trailing spaces.
|
|
* Return the remainder string after the @separator.
|
|
*/
|
|
static char __init *str_field_delimit(char **str, char separator)
|
|
{
|
|
char *s;
|
|
|
|
/* TODO: add support for escaped characters */
|
|
*str = skip_spaces(*str);
|
|
s = strchr(*str, separator);
|
|
/* Delimit the field and remove trailing spaces */
|
|
if (s)
|
|
*s = '\0';
|
|
*str = strim(*str);
|
|
return s ? ++s : NULL;
|
|
}
|
|
|
|
/**
|
|
* dm_parse_table_entry - parse a table entry
|
|
* @dev: device to store the parsed information.
|
|
* @str: the pointer to a string with the format:
|
|
* <start_sector> <num_sectors> <target_type> <target_args>[, ...]
|
|
*
|
|
* Return the remainder string after the table entry, i.e, after the comma which
|
|
* delimits the entry or NULL if reached the end of the string.
|
|
*/
|
|
static char __init *dm_parse_table_entry(struct dm_device *dev, char *str)
|
|
{
|
|
const unsigned int n = dev->dmi.target_count - 1;
|
|
struct dm_target_spec *sp;
|
|
unsigned int i;
|
|
/* fields: */
|
|
char *field[4];
|
|
char *next;
|
|
|
|
field[0] = str;
|
|
/* Delimit first 3 fields that are separated by space */
|
|
for (i = 0; i < ARRAY_SIZE(field) - 1; i++) {
|
|
field[i + 1] = str_field_delimit(&field[i], ' ');
|
|
if (!field[i + 1])
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
/* Delimit last field that can be terminated by comma */
|
|
next = str_field_delimit(&field[i], ',');
|
|
|
|
sp = kzalloc(sizeof(*sp), GFP_KERNEL);
|
|
if (!sp)
|
|
return ERR_PTR(-ENOMEM);
|
|
dev->table[n] = sp;
|
|
|
|
/* start_sector */
|
|
if (kstrtoull(field[0], 0, &sp->sector_start))
|
|
return ERR_PTR(-EINVAL);
|
|
/* num_sector */
|
|
if (kstrtoull(field[1], 0, &sp->length))
|
|
return ERR_PTR(-EINVAL);
|
|
/* target_type */
|
|
strscpy(sp->target_type, field[2], sizeof(sp->target_type));
|
|
if (dm_verify_target_type(sp->target_type)) {
|
|
DMERR("invalid type \"%s\"", sp->target_type);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
/* target_args */
|
|
dev->target_args_array[n] = kstrndup(field[3], DM_MAX_STR_SIZE,
|
|
GFP_KERNEL);
|
|
if (!dev->target_args_array[n])
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
return next;
|
|
}
|
|
|
|
/**
|
|
* dm_parse_table - parse "dm-mod.create=" table field
|
|
* @dev: device to store the parsed information.
|
|
* @str: the pointer to a string with the format:
|
|
* <table>[,<table>+]
|
|
*/
|
|
static int __init dm_parse_table(struct dm_device *dev, char *str)
|
|
{
|
|
char *table_entry = str;
|
|
|
|
while (table_entry) {
|
|
DMDEBUG("parsing table \"%s\"", str);
|
|
if (++dev->dmi.target_count > DM_MAX_TARGETS) {
|
|
DMERR("too many targets %u > %d",
|
|
dev->dmi.target_count, DM_MAX_TARGETS);
|
|
return -EINVAL;
|
|
}
|
|
table_entry = dm_parse_table_entry(dev, table_entry);
|
|
if (IS_ERR(table_entry)) {
|
|
DMERR("couldn't parse table");
|
|
return PTR_ERR(table_entry);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* dm_parse_device_entry - parse a device entry
|
|
* @dev: device to store the parsed information.
|
|
* @str: the pointer to a string with the format:
|
|
* name,uuid,minor,flags,table[; ...]
|
|
*
|
|
* Return the remainder string after the table entry, i.e, after the semi-colon
|
|
* which delimits the entry or NULL if reached the end of the string.
|
|
*/
|
|
static char __init *dm_parse_device_entry(struct dm_device *dev, char *str)
|
|
{
|
|
/* There are 5 fields: name,uuid,minor,flags,table; */
|
|
char *field[5];
|
|
unsigned int i;
|
|
char *next;
|
|
|
|
field[0] = str;
|
|
/* Delimit first 4 fields that are separated by comma */
|
|
for (i = 0; i < ARRAY_SIZE(field) - 1; i++) {
|
|
field[i+1] = str_field_delimit(&field[i], ',');
|
|
if (!field[i+1])
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
/* Delimit last field that can be delimited by semi-colon */
|
|
next = str_field_delimit(&field[i], ';');
|
|
|
|
/* name */
|
|
strscpy(dev->dmi.name, field[0], sizeof(dev->dmi.name));
|
|
/* uuid */
|
|
strscpy(dev->dmi.uuid, field[1], sizeof(dev->dmi.uuid));
|
|
/* minor */
|
|
if (strlen(field[2])) {
|
|
if (kstrtoull(field[2], 0, &dev->dmi.dev) ||
|
|
dev->dmi.dev >= (1 << MINORBITS))
|
|
return ERR_PTR(-EINVAL);
|
|
dev->dmi.dev = huge_encode_dev((dev_t)dev->dmi.dev);
|
|
dev->dmi.flags |= DM_PERSISTENT_DEV_FLAG;
|
|
}
|
|
/* flags */
|
|
if (!strcmp(field[3], "ro"))
|
|
dev->dmi.flags |= DM_READONLY_FLAG;
|
|
else if (strcmp(field[3], "rw"))
|
|
return ERR_PTR(-EINVAL);
|
|
/* table */
|
|
if (dm_parse_table(dev, field[4]))
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
return next;
|
|
}
|
|
|
|
/**
|
|
* dm_parse_devices - parse "dm-mod.create=" argument
|
|
* @devices: list of struct dm_device to store the parsed information.
|
|
* @str: the pointer to a string with the format:
|
|
* <device>[;<device>+]
|
|
*/
|
|
static int __init dm_parse_devices(struct list_head *devices, char *str)
|
|
{
|
|
unsigned long ndev = 0;
|
|
struct dm_device *dev;
|
|
char *device = str;
|
|
|
|
DMDEBUG("parsing \"%s\"", str);
|
|
while (device) {
|
|
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
|
|
if (!dev)
|
|
return -ENOMEM;
|
|
list_add_tail(&dev->list, devices);
|
|
|
|
if (++ndev > DM_MAX_DEVICES) {
|
|
DMERR("too many devices %lu > %d",
|
|
ndev, DM_MAX_DEVICES);
|
|
return -EINVAL;
|
|
}
|
|
|
|
device = dm_parse_device_entry(dev, device);
|
|
if (IS_ERR(device)) {
|
|
DMERR("couldn't parse device");
|
|
return PTR_ERR(device);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* dm_init_init - parse "dm-mod.create=" argument and configure drivers
|
|
*/
|
|
static int __init dm_init_init(void)
|
|
{
|
|
struct dm_device *dev;
|
|
LIST_HEAD(devices);
|
|
char *str;
|
|
int i, r;
|
|
|
|
if (!create)
|
|
return 0;
|
|
|
|
if (strlen(create) >= DM_MAX_STR_SIZE) {
|
|
DMERR("Argument is too big. Limit is %d", DM_MAX_STR_SIZE);
|
|
return -EINVAL;
|
|
}
|
|
str = kstrndup(create, DM_MAX_STR_SIZE, GFP_KERNEL);
|
|
if (!str)
|
|
return -ENOMEM;
|
|
|
|
r = dm_parse_devices(&devices, str);
|
|
if (r)
|
|
goto out;
|
|
|
|
DMINFO("waiting for all devices to be available before creating mapped devices");
|
|
wait_for_device_probe();
|
|
|
|
for (i = 0; i < ARRAY_SIZE(waitfor); i++) {
|
|
if (waitfor[i]) {
|
|
DMINFO("waiting for device %s ...", waitfor[i]);
|
|
while (!dm_get_dev_t(waitfor[i]))
|
|
msleep(5);
|
|
}
|
|
}
|
|
|
|
if (waitfor[0])
|
|
DMINFO("all devices available");
|
|
|
|
list_for_each_entry(dev, &devices, list) {
|
|
if (dm_early_create(&dev->dmi, dev->table,
|
|
dev->target_args_array))
|
|
break;
|
|
}
|
|
out:
|
|
kfree(str);
|
|
dm_setup_cleanup(&devices);
|
|
return r;
|
|
}
|
|
|
|
late_initcall(dm_init_init);
|
|
|
|
module_param(create, charp, 0);
|
|
MODULE_PARM_DESC(create, "Create a mapped device in early boot");
|
|
|
|
/* ---------------------------------------------------------------
|
|
* ChromeOS shim - convert dm= format to dm-mod.create= format
|
|
* ---------------------------------------------------------------
|
|
*/
|
|
|
|
struct dm_chrome_target {
|
|
char *field[4];
|
|
};
|
|
|
|
struct dm_chrome_dev {
|
|
char *name, *uuid, *mode;
|
|
unsigned int num_targets;
|
|
struct dm_chrome_target targets[DM_MAX_TARGETS];
|
|
};
|
|
|
|
static char __init *dm_chrome_parse_target(char *str, struct dm_chrome_target *tgt)
|
|
{
|
|
unsigned int i;
|
|
|
|
tgt->field[0] = str;
|
|
/* Delimit first 3 fields that are separated by space */
|
|
for (i = 0; i < ARRAY_SIZE(tgt->field) - 1; i++) {
|
|
tgt->field[i + 1] = str_field_delimit(&tgt->field[i], ' ');
|
|
if (!tgt->field[i + 1])
|
|
return NULL;
|
|
}
|
|
/* Delimit last field that can be terminated by comma */
|
|
return str_field_delimit(&tgt->field[i], ',');
|
|
}
|
|
|
|
static char __init *dm_chrome_parse_dev(char *str, struct dm_chrome_dev *dev)
|
|
{
|
|
char *target, *num;
|
|
unsigned int i;
|
|
|
|
if (!str)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
target = str_field_delimit(&str, ',');
|
|
if (!target)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
/* Delimit first 3 fields that are separated by space */
|
|
dev->name = str;
|
|
dev->uuid = str_field_delimit(&dev->name, ' ');
|
|
if (!dev->uuid)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
dev->mode = str_field_delimit(&dev->uuid, ' ');
|
|
if (!dev->mode)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
/* num is optional */
|
|
num = str_field_delimit(&dev->mode, ' ');
|
|
if (!num)
|
|
dev->num_targets = 1;
|
|
else {
|
|
/* Delimit num and check if it the last field */
|
|
if(str_field_delimit(&num, ' '))
|
|
return ERR_PTR(-EINVAL);
|
|
if (kstrtouint(num, 0, &dev->num_targets))
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
if (dev->num_targets > DM_MAX_TARGETS) {
|
|
DMERR("too many targets %u > %d",
|
|
dev->num_targets, DM_MAX_TARGETS);
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
|
|
for (i = 0; i < dev->num_targets - 1; i++) {
|
|
target = dm_chrome_parse_target(target, &dev->targets[i]);
|
|
if (!target)
|
|
return ERR_PTR(-EINVAL);
|
|
}
|
|
/* The last one can return NULL if it reaches the end of str */
|
|
return dm_chrome_parse_target(target, &dev->targets[i]);
|
|
}
|
|
|
|
static char __init *dm_chrome_convert(struct dm_chrome_dev *devs, unsigned int num_devs)
|
|
{
|
|
char *str = kmalloc(DM_MAX_STR_SIZE, GFP_KERNEL);
|
|
char *p = str;
|
|
unsigned int i, j;
|
|
int ret;
|
|
|
|
if (!str)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
for (i = 0; i < num_devs; i++) {
|
|
if (!strcmp(devs[i].uuid, "none"))
|
|
devs[i].uuid = "";
|
|
ret = snprintf(p, DM_MAX_STR_SIZE - (p - str),
|
|
"%s,%s,,%s",
|
|
devs[i].name,
|
|
devs[i].uuid,
|
|
devs[i].mode);
|
|
if (ret < 0)
|
|
goto out;
|
|
p += ret;
|
|
|
|
for (j = 0; j < devs[i].num_targets; j++) {
|
|
ret = snprintf(p, DM_MAX_STR_SIZE - (p - str),
|
|
",%s %s %s %s",
|
|
devs[i].targets[j].field[0],
|
|
devs[i].targets[j].field[1],
|
|
devs[i].targets[j].field[2],
|
|
devs[i].targets[j].field[3]);
|
|
if (ret < 0)
|
|
goto out;
|
|
p += ret;
|
|
}
|
|
if (i < num_devs - 1) {
|
|
ret = snprintf(p, DM_MAX_STR_SIZE - (p - str), ";");
|
|
if (ret < 0)
|
|
goto out;
|
|
p += ret;
|
|
}
|
|
}
|
|
|
|
return str;
|
|
|
|
out:
|
|
kfree(str);
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
/**
|
|
* dm_chrome_shim - convert old dm= format used in chromeos to the new
|
|
* upstream format.
|
|
*
|
|
* ChromeOS old format
|
|
* -------------------
|
|
* <device> ::= [<num>] <device-mapper>+
|
|
* <device-mapper> ::= <head> "," <target>+
|
|
* <head> ::= <name> <uuid> <mode> [<num>]
|
|
* <target> ::= <start> <length> <type> <options> ","
|
|
* <mode> ::= "ro" | "rw"
|
|
* <uuid> ::= xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx | "none"
|
|
* <type> ::= "verity" | "bootcache" | ...
|
|
*
|
|
* Example:
|
|
* 2 vboot none ro 1,
|
|
* 0 1768000 bootcache
|
|
* device=aa55b119-2a47-8c45-946a-5ac57765011f+1
|
|
* signature=76e9be054b15884a9fa85973e9cb274c93afadb6
|
|
* cache_start=1768000 max_blocks=100000 size_limit=23 max_trace=20000,
|
|
* vroot none ro 1,
|
|
* 0 1740800 verity payload=254:0 hashtree=254:0 hashstart=1740800 alg=sha1
|
|
* root_hexdigest=76e9be054b15884a9fa85973e9cb274c93afadb6
|
|
* salt=5b3549d54d6c7a3837b9b81ed72e49463a64c03680c47835bef94d768e5646fe
|
|
*
|
|
* Notes:
|
|
* 1. uuid is a label for the device and we set it to "none".
|
|
* 2. The <num> field will be optional initially and assumed to be 1.
|
|
* Once all the scripts that set these fields have been set, it will
|
|
* be made mandatory.
|
|
*/
|
|
|
|
static char *chrome_create;
|
|
|
|
static int __init dm_chrome_shim(char *arg) {
|
|
if (!arg || create)
|
|
return -EINVAL;
|
|
chrome_create = arg;
|
|
return 0;
|
|
}
|
|
|
|
static int __init dm_chrome_parse_devices(void)
|
|
{
|
|
struct dm_chrome_dev *devs;
|
|
unsigned int num_devs, i;
|
|
char *next, *base_str;
|
|
int ret = 0;
|
|
|
|
/* Verify if dm-mod.create was not used */
|
|
if (!chrome_create || create)
|
|
return -EINVAL;
|
|
|
|
if (strlen(chrome_create) >= DM_MAX_STR_SIZE) {
|
|
DMERR("Argument is too big. Limit is %d\n", DM_MAX_STR_SIZE);
|
|
return -EINVAL;
|
|
}
|
|
|
|
base_str = kstrdup(chrome_create, GFP_KERNEL);
|
|
if (!base_str)
|
|
return -ENOMEM;
|
|
|
|
next = str_field_delimit(&base_str, ' ');
|
|
if (!next) {
|
|
ret = -EINVAL;
|
|
goto out_str;
|
|
}
|
|
|
|
/* if first field is not the optional <num> field */
|
|
if (kstrtouint(base_str, 0, &num_devs)) {
|
|
num_devs = 1;
|
|
/* rewind next pointer */
|
|
next = base_str;
|
|
}
|
|
|
|
if (num_devs > DM_MAX_DEVICES) {
|
|
DMERR("too many devices %u > %d", num_devs, DM_MAX_DEVICES);
|
|
ret = -EINVAL;
|
|
goto out_str;
|
|
}
|
|
|
|
devs = kcalloc(num_devs, sizeof(*devs), GFP_KERNEL);
|
|
if (!devs)
|
|
return -ENOMEM;
|
|
|
|
/* restore string */
|
|
strcpy(base_str, chrome_create);
|
|
|
|
/* parse devices */
|
|
for (i = 0; i < num_devs; i++) {
|
|
next = dm_chrome_parse_dev(next, &devs[i]);
|
|
if (IS_ERR(next)) {
|
|
DMERR("couldn't parse device");
|
|
ret = PTR_ERR(next);
|
|
goto out_devs;
|
|
}
|
|
}
|
|
|
|
create = dm_chrome_convert(devs, num_devs);
|
|
if (IS_ERR(create)) {
|
|
ret = PTR_ERR(create);
|
|
goto out_devs;
|
|
}
|
|
|
|
DMDEBUG("Converting:\n\tdm=\"%s\"\n\tdm-mod.create=\"%s\"\n",
|
|
chrome_create, create);
|
|
|
|
/* Call upstream code */
|
|
dm_init_init();
|
|
|
|
kfree(create);
|
|
|
|
out_devs:
|
|
create = NULL;
|
|
kfree(devs);
|
|
out_str:
|
|
kfree(base_str);
|
|
|
|
return ret;
|
|
}
|
|
|
|
late_initcall(dm_chrome_parse_devices);
|
|
|
|
__setup("dm=", dm_chrome_shim);
|
|
|
|
module_param_array(waitfor, charp, NULL, 0);
|
|
MODULE_PARM_DESC(waitfor, "Devices to wait for before setting up tables");
|