kernel-ark/drivers/firmware/dmi_scan.c
Tony Luck d114a33387 dmi: Feed DMI table to /dev/random driver
Send the entire DMI (SMBIOS) table to the /dev/random driver to
help seed its pools.

Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2012-07-24 13:16:41 -04:00

753 lines
18 KiB
C

#include <linux/types.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/dmi.h>
#include <linux/efi.h>
#include <linux/bootmem.h>
#include <linux/random.h>
#include <asm/dmi.h>
/*
* DMI stands for "Desktop Management Interface". It is part
* of and an antecedent to, SMBIOS, which stands for System
* Management BIOS. See further: http://www.dmtf.org/standards
*/
static char dmi_empty_string[] = " ";
/*
* Catch too early calls to dmi_check_system():
*/
static int dmi_initialized;
static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
{
const u8 *bp = ((u8 *) dm) + dm->length;
if (s) {
s--;
while (s > 0 && *bp) {
bp += strlen(bp) + 1;
s--;
}
if (*bp != 0) {
size_t len = strlen(bp)+1;
size_t cmp_len = len > 8 ? 8 : len;
if (!memcmp(bp, dmi_empty_string, cmp_len))
return dmi_empty_string;
return bp;
}
}
return "";
}
static char * __init dmi_string(const struct dmi_header *dm, u8 s)
{
const char *bp = dmi_string_nosave(dm, s);
char *str;
size_t len;
if (bp == dmi_empty_string)
return dmi_empty_string;
len = strlen(bp) + 1;
str = dmi_alloc(len);
if (str != NULL)
strcpy(str, bp);
else
printk(KERN_ERR "dmi_string: cannot allocate %Zu bytes.\n", len);
return str;
}
/*
* We have to be cautious here. We have seen BIOSes with DMI pointers
* pointing to completely the wrong place for example
*/
static void dmi_table(u8 *buf, int len, int num,
void (*decode)(const struct dmi_header *, void *),
void *private_data)
{
u8 *data = buf;
int i = 0;
/*
* Stop when we see all the items the table claimed to have
* OR we run off the end of the table (also happens)
*/
while ((i < num) && (data - buf + sizeof(struct dmi_header)) <= len) {
const struct dmi_header *dm = (const struct dmi_header *)data;
/*
* We want to know the total length (formatted area and
* strings) before decoding to make sure we won't run off the
* table in dmi_decode or dmi_string
*/
data += dm->length;
while ((data - buf < len - 1) && (data[0] || data[1]))
data++;
if (data - buf < len - 1)
decode(dm, private_data);
data += 2;
i++;
}
}
static u32 dmi_base;
static u16 dmi_len;
static u16 dmi_num;
static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
void *))
{
u8 *buf;
buf = dmi_ioremap(dmi_base, dmi_len);
if (buf == NULL)
return -1;
dmi_table(buf, dmi_len, dmi_num, decode, NULL);
add_device_randomness(buf, dmi_len);
dmi_iounmap(buf, dmi_len);
return 0;
}
static int __init dmi_checksum(const u8 *buf)
{
u8 sum = 0;
int a;
for (a = 0; a < 15; a++)
sum += buf[a];
return sum == 0;
}
static char *dmi_ident[DMI_STRING_MAX];
static LIST_HEAD(dmi_devices);
int dmi_available;
/*
* Save a DMI string
*/
static void __init dmi_save_ident(const struct dmi_header *dm, int slot, int string)
{
const char *d = (const char*) dm;
char *p;
if (dmi_ident[slot])
return;
p = dmi_string(dm, d[string]);
if (p == NULL)
return;
dmi_ident[slot] = p;
}
static void __init dmi_save_uuid(const struct dmi_header *dm, int slot, int index)
{
const u8 *d = (u8*) dm + index;
char *s;
int is_ff = 1, is_00 = 1, i;
if (dmi_ident[slot])
return;
for (i = 0; i < 16 && (is_ff || is_00); i++) {
if(d[i] != 0x00) is_ff = 0;
if(d[i] != 0xFF) is_00 = 0;
}
if (is_ff || is_00)
return;
s = dmi_alloc(16*2+4+1);
if (!s)
return;
sprintf(s, "%pUB", d);
dmi_ident[slot] = s;
}
static void __init dmi_save_type(const struct dmi_header *dm, int slot, int index)
{
const u8 *d = (u8*) dm + index;
char *s;
if (dmi_ident[slot])
return;
s = dmi_alloc(4);
if (!s)
return;
sprintf(s, "%u", *d & 0x7F);
dmi_ident[slot] = s;
}
static void __init dmi_save_one_device(int type, const char *name)
{
struct dmi_device *dev;
/* No duplicate device */
if (dmi_find_device(type, name, NULL))
return;
dev = dmi_alloc(sizeof(*dev) + strlen(name) + 1);
if (!dev) {
printk(KERN_ERR "dmi_save_one_device: out of memory.\n");
return;
}
dev->type = type;
strcpy((char *)(dev + 1), name);
dev->name = (char *)(dev + 1);
dev->device_data = NULL;
list_add(&dev->list, &dmi_devices);
}
static void __init dmi_save_devices(const struct dmi_header *dm)
{
int i, count = (dm->length - sizeof(struct dmi_header)) / 2;
for (i = 0; i < count; i++) {
const char *d = (char *)(dm + 1) + (i * 2);
/* Skip disabled device */
if ((*d & 0x80) == 0)
continue;
dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d + 1)));
}
}
static void __init dmi_save_oem_strings_devices(const struct dmi_header *dm)
{
int i, count = *(u8 *)(dm + 1);
struct dmi_device *dev;
for (i = 1; i <= count; i++) {
char *devname = dmi_string(dm, i);
if (devname == dmi_empty_string)
continue;
dev = dmi_alloc(sizeof(*dev));
if (!dev) {
printk(KERN_ERR
"dmi_save_oem_strings_devices: out of memory.\n");
break;
}
dev->type = DMI_DEV_TYPE_OEM_STRING;
dev->name = devname;
dev->device_data = NULL;
list_add(&dev->list, &dmi_devices);
}
}
static void __init dmi_save_ipmi_device(const struct dmi_header *dm)
{
struct dmi_device *dev;
void * data;
data = dmi_alloc(dm->length);
if (data == NULL) {
printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
return;
}
memcpy(data, dm, dm->length);
dev = dmi_alloc(sizeof(*dev));
if (!dev) {
printk(KERN_ERR "dmi_save_ipmi_device: out of memory.\n");
return;
}
dev->type = DMI_DEV_TYPE_IPMI;
dev->name = "IPMI controller";
dev->device_data = data;
list_add_tail(&dev->list, &dmi_devices);
}
static void __init dmi_save_dev_onboard(int instance, int segment, int bus,
int devfn, const char *name)
{
struct dmi_dev_onboard *onboard_dev;
onboard_dev = dmi_alloc(sizeof(*onboard_dev) + strlen(name) + 1);
if (!onboard_dev) {
printk(KERN_ERR "dmi_save_dev_onboard: out of memory.\n");
return;
}
onboard_dev->instance = instance;
onboard_dev->segment = segment;
onboard_dev->bus = bus;
onboard_dev->devfn = devfn;
strcpy((char *)&onboard_dev[1], name);
onboard_dev->dev.type = DMI_DEV_TYPE_DEV_ONBOARD;
onboard_dev->dev.name = (char *)&onboard_dev[1];
onboard_dev->dev.device_data = onboard_dev;
list_add(&onboard_dev->dev.list, &dmi_devices);
}
static void __init dmi_save_extended_devices(const struct dmi_header *dm)
{
const u8 *d = (u8*) dm + 5;
/* Skip disabled device */
if ((*d & 0x80) == 0)
return;
dmi_save_dev_onboard(*(d+1), *(u16 *)(d+2), *(d+4), *(d+5),
dmi_string_nosave(dm, *(d-1)));
dmi_save_one_device(*d & 0x7f, dmi_string_nosave(dm, *(d - 1)));
}
/*
* Process a DMI table entry. Right now all we care about are the BIOS
* and machine entries. For 2.5 we should pull the smbus controller info
* out of here.
*/
static void __init dmi_decode(const struct dmi_header *dm, void *dummy)
{
switch(dm->type) {
case 0: /* BIOS Information */
dmi_save_ident(dm, DMI_BIOS_VENDOR, 4);
dmi_save_ident(dm, DMI_BIOS_VERSION, 5);
dmi_save_ident(dm, DMI_BIOS_DATE, 8);
break;
case 1: /* System Information */
dmi_save_ident(dm, DMI_SYS_VENDOR, 4);
dmi_save_ident(dm, DMI_PRODUCT_NAME, 5);
dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
dmi_save_uuid(dm, DMI_PRODUCT_UUID, 8);
break;
case 2: /* Base Board Information */
dmi_save_ident(dm, DMI_BOARD_VENDOR, 4);
dmi_save_ident(dm, DMI_BOARD_NAME, 5);
dmi_save_ident(dm, DMI_BOARD_VERSION, 6);
dmi_save_ident(dm, DMI_BOARD_SERIAL, 7);
dmi_save_ident(dm, DMI_BOARD_ASSET_TAG, 8);
break;
case 3: /* Chassis Information */
dmi_save_ident(dm, DMI_CHASSIS_VENDOR, 4);
dmi_save_type(dm, DMI_CHASSIS_TYPE, 5);
dmi_save_ident(dm, DMI_CHASSIS_VERSION, 6);
dmi_save_ident(dm, DMI_CHASSIS_SERIAL, 7);
dmi_save_ident(dm, DMI_CHASSIS_ASSET_TAG, 8);
break;
case 10: /* Onboard Devices Information */
dmi_save_devices(dm);
break;
case 11: /* OEM Strings */
dmi_save_oem_strings_devices(dm);
break;
case 38: /* IPMI Device Information */
dmi_save_ipmi_device(dm);
break;
case 41: /* Onboard Devices Extended Information */
dmi_save_extended_devices(dm);
}
}
static void __init print_filtered(const char *info)
{
const char *p;
if (!info)
return;
for (p = info; *p; p++)
if (isprint(*p))
printk(KERN_CONT "%c", *p);
else
printk(KERN_CONT "\\x%02x", *p & 0xff);
}
static void __init dmi_dump_ids(void)
{
const char *board; /* Board Name is optional */
printk(KERN_DEBUG "DMI: ");
print_filtered(dmi_get_system_info(DMI_SYS_VENDOR));
printk(KERN_CONT " ");
print_filtered(dmi_get_system_info(DMI_PRODUCT_NAME));
board = dmi_get_system_info(DMI_BOARD_NAME);
if (board) {
printk(KERN_CONT "/");
print_filtered(board);
}
printk(KERN_CONT ", BIOS ");
print_filtered(dmi_get_system_info(DMI_BIOS_VERSION));
printk(KERN_CONT " ");
print_filtered(dmi_get_system_info(DMI_BIOS_DATE));
printk(KERN_CONT "\n");
}
static int __init dmi_present(const char __iomem *p)
{
u8 buf[15];
memcpy_fromio(buf, p, 15);
if ((memcmp(buf, "_DMI_", 5) == 0) && dmi_checksum(buf)) {
dmi_num = (buf[13] << 8) | buf[12];
dmi_len = (buf[7] << 8) | buf[6];
dmi_base = (buf[11] << 24) | (buf[10] << 16) |
(buf[9] << 8) | buf[8];
/*
* DMI version 0.0 means that the real version is taken from
* the SMBIOS version, which we don't know at this point.
*/
if (buf[14] != 0)
printk(KERN_INFO "DMI %d.%d present.\n",
buf[14] >> 4, buf[14] & 0xF);
else
printk(KERN_INFO "DMI present.\n");
if (dmi_walk_early(dmi_decode) == 0) {
dmi_dump_ids();
return 0;
}
}
return 1;
}
void __init dmi_scan_machine(void)
{
char __iomem *p, *q;
int rc;
if (efi_enabled) {
if (efi.smbios == EFI_INVALID_TABLE_ADDR)
goto error;
/* This is called as a core_initcall() because it isn't
* needed during early boot. This also means we can
* iounmap the space when we're done with it.
*/
p = dmi_ioremap(efi.smbios, 32);
if (p == NULL)
goto error;
rc = dmi_present(p + 0x10); /* offset of _DMI_ string */
dmi_iounmap(p, 32);
if (!rc) {
dmi_available = 1;
goto out;
}
}
else {
/*
* no iounmap() for that ioremap(); it would be a no-op, but
* it's so early in setup that sucker gets confused into doing
* what it shouldn't if we actually call it.
*/
p = dmi_ioremap(0xF0000, 0x10000);
if (p == NULL)
goto error;
for (q = p; q < p + 0x10000; q += 16) {
rc = dmi_present(q);
if (!rc) {
dmi_available = 1;
dmi_iounmap(p, 0x10000);
goto out;
}
}
dmi_iounmap(p, 0x10000);
}
error:
printk(KERN_INFO "DMI not present or invalid.\n");
out:
dmi_initialized = 1;
}
/**
* dmi_matches - check if dmi_system_id structure matches system DMI data
* @dmi: pointer to the dmi_system_id structure to check
*/
static bool dmi_matches(const struct dmi_system_id *dmi)
{
int i;
WARN(!dmi_initialized, KERN_ERR "dmi check: not initialized yet.\n");
for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
int s = dmi->matches[i].slot;
if (s == DMI_NONE)
break;
if (dmi_ident[s]
&& strstr(dmi_ident[s], dmi->matches[i].substr))
continue;
/* No match */
return false;
}
return true;
}
/**
* dmi_is_end_of_table - check for end-of-table marker
* @dmi: pointer to the dmi_system_id structure to check
*/
static bool dmi_is_end_of_table(const struct dmi_system_id *dmi)
{
return dmi->matches[0].slot == DMI_NONE;
}
/**
* dmi_check_system - check system DMI data
* @list: array of dmi_system_id structures to match against
* All non-null elements of the list must match
* their slot's (field index's) data (i.e., each
* list string must be a substring of the specified
* DMI slot's string data) to be considered a
* successful match.
*
* Walk the blacklist table running matching functions until someone
* returns non zero or we hit the end. Callback function is called for
* each successful match. Returns the number of matches.
*/
int dmi_check_system(const struct dmi_system_id *list)
{
int count = 0;
const struct dmi_system_id *d;
for (d = list; !dmi_is_end_of_table(d); d++)
if (dmi_matches(d)) {
count++;
if (d->callback && d->callback(d))
break;
}
return count;
}
EXPORT_SYMBOL(dmi_check_system);
/**
* dmi_first_match - find dmi_system_id structure matching system DMI data
* @list: array of dmi_system_id structures to match against
* All non-null elements of the list must match
* their slot's (field index's) data (i.e., each
* list string must be a substring of the specified
* DMI slot's string data) to be considered a
* successful match.
*
* Walk the blacklist table until the first match is found. Return the
* pointer to the matching entry or NULL if there's no match.
*/
const struct dmi_system_id *dmi_first_match(const struct dmi_system_id *list)
{
const struct dmi_system_id *d;
for (d = list; !dmi_is_end_of_table(d); d++)
if (dmi_matches(d))
return d;
return NULL;
}
EXPORT_SYMBOL(dmi_first_match);
/**
* dmi_get_system_info - return DMI data value
* @field: data index (see enum dmi_field)
*
* Returns one DMI data value, can be used to perform
* complex DMI data checks.
*/
const char *dmi_get_system_info(int field)
{
return dmi_ident[field];
}
EXPORT_SYMBOL(dmi_get_system_info);
/**
* dmi_name_in_serial - Check if string is in the DMI product serial information
* @str: string to check for
*/
int dmi_name_in_serial(const char *str)
{
int f = DMI_PRODUCT_SERIAL;
if (dmi_ident[f] && strstr(dmi_ident[f], str))
return 1;
return 0;
}
/**
* dmi_name_in_vendors - Check if string is in the DMI system or board vendor name
* @str: Case sensitive Name
*/
int dmi_name_in_vendors(const char *str)
{
static int fields[] = { DMI_SYS_VENDOR, DMI_BOARD_VENDOR, DMI_NONE };
int i;
for (i = 0; fields[i] != DMI_NONE; i++) {
int f = fields[i];
if (dmi_ident[f] && strstr(dmi_ident[f], str))
return 1;
}
return 0;
}
EXPORT_SYMBOL(dmi_name_in_vendors);
/**
* dmi_find_device - find onboard device by type/name
* @type: device type or %DMI_DEV_TYPE_ANY to match all device types
* @name: device name string or %NULL to match all
* @from: previous device found in search, or %NULL for new search.
*
* Iterates through the list of known onboard devices. If a device is
* found with a matching @vendor and @device, a pointer to its device
* structure is returned. Otherwise, %NULL is returned.
* A new search is initiated by passing %NULL as the @from argument.
* If @from is not %NULL, searches continue from next device.
*/
const struct dmi_device * dmi_find_device(int type, const char *name,
const struct dmi_device *from)
{
const struct list_head *head = from ? &from->list : &dmi_devices;
struct list_head *d;
for(d = head->next; d != &dmi_devices; d = d->next) {
const struct dmi_device *dev =
list_entry(d, struct dmi_device, list);
if (((type == DMI_DEV_TYPE_ANY) || (dev->type == type)) &&
((name == NULL) || (strcmp(dev->name, name) == 0)))
return dev;
}
return NULL;
}
EXPORT_SYMBOL(dmi_find_device);
/**
* dmi_get_date - parse a DMI date
* @field: data index (see enum dmi_field)
* @yearp: optional out parameter for the year
* @monthp: optional out parameter for the month
* @dayp: optional out parameter for the day
*
* The date field is assumed to be in the form resembling
* [mm[/dd]]/yy[yy] and the result is stored in the out
* parameters any or all of which can be omitted.
*
* If the field doesn't exist, all out parameters are set to zero
* and false is returned. Otherwise, true is returned with any
* invalid part of date set to zero.
*
* On return, year, month and day are guaranteed to be in the
* range of [0,9999], [0,12] and [0,31] respectively.
*/
bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp)
{
int year = 0, month = 0, day = 0;
bool exists;
const char *s, *y;
char *e;
s = dmi_get_system_info(field);
exists = s;
if (!exists)
goto out;
/*
* Determine year first. We assume the date string resembles
* mm/dd/yy[yy] but the original code extracted only the year
* from the end. Keep the behavior in the spirit of no
* surprises.
*/
y = strrchr(s, '/');
if (!y)
goto out;
y++;
year = simple_strtoul(y, &e, 10);
if (y != e && year < 100) { /* 2-digit year */
year += 1900;
if (year < 1996) /* no dates < spec 1.0 */
year += 100;
}
if (year > 9999) /* year should fit in %04d */
year = 0;
/* parse the mm and dd */
month = simple_strtoul(s, &e, 10);
if (s == e || *e != '/' || !month || month > 12) {
month = 0;
goto out;
}
s = e + 1;
day = simple_strtoul(s, &e, 10);
if (s == y || s == e || *e != '/' || day > 31)
day = 0;
out:
if (yearp)
*yearp = year;
if (monthp)
*monthp = month;
if (dayp)
*dayp = day;
return exists;
}
EXPORT_SYMBOL(dmi_get_date);
/**
* dmi_walk - Walk the DMI table and get called back for every record
* @decode: Callback function
* @private_data: Private data to be passed to the callback function
*
* Returns -1 when the DMI table can't be reached, 0 on success.
*/
int dmi_walk(void (*decode)(const struct dmi_header *, void *),
void *private_data)
{
u8 *buf;
if (!dmi_available)
return -1;
buf = ioremap(dmi_base, dmi_len);
if (buf == NULL)
return -1;
dmi_table(buf, dmi_len, dmi_num, decode, private_data);
iounmap(buf);
return 0;
}
EXPORT_SYMBOL_GPL(dmi_walk);
/**
* dmi_match - compare a string to the dmi field (if exists)
* @f: DMI field identifier
* @str: string to compare the DMI field to
*
* Returns true if the requested field equals to the str (including NULL).
*/
bool dmi_match(enum dmi_field f, const char *str)
{
const char *info = dmi_get_system_info(f);
if (info == NULL || str == NULL)
return info == str;
return !strcmp(info, str);
}
EXPORT_SYMBOL_GPL(dmi_match);