u-boot/lib/efi_loader/efi_device_path.c
Heinrich Schuchardt 5cad4a3093 efi_loader: efi_dp_check_length()
We need to check that device paths provided via UEFI variables are not
malformed.

Provide function efi_dp_check_length() to check if a device path has an
end node within a given number of bytes.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-24 16:37:53 +02:00

1163 lines
28 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* EFI device path from u-boot device-model mapping
*
* (C) Copyright 2017 Rob Clark
*/
#include <common.h>
#include <blk.h>
#include <dm.h>
#include <log.h>
#include <net.h>
#include <usb.h>
#include <mmc.h>
#include <nvme.h>
#include <efi_loader.h>
#include <part.h>
#include <sandboxblockdev.h>
#include <asm-generic/unaligned.h>
#include <linux/compat.h> /* U16_MAX */
#ifdef CONFIG_SANDBOX
const efi_guid_t efi_guid_host_dev = U_BOOT_HOST_DEV_GUID;
#endif
#ifdef CONFIG_VIRTIO_BLK
const efi_guid_t efi_guid_virtio_dev = U_BOOT_VIRTIO_DEV_GUID;
#endif
/* template END node: */
static const struct efi_device_path END = {
.type = DEVICE_PATH_TYPE_END,
.sub_type = DEVICE_PATH_SUB_TYPE_END,
.length = sizeof(END),
};
/* template ROOT node: */
static const struct efi_device_path_vendor ROOT = {
.dp = {
.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE,
.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR,
.length = sizeof(ROOT),
},
.guid = U_BOOT_GUID,
};
#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
/*
* Determine if an MMC device is an SD card.
*
* @desc block device descriptor
* @return true if the device is an SD card
*/
static bool is_sd(struct blk_desc *desc)
{
struct mmc *mmc = find_mmc_device(desc->devnum);
if (!mmc)
return false;
return IS_SD(mmc) != 0U;
}
#endif
static void *dp_alloc(size_t sz)
{
void *buf;
if (efi_allocate_pool(EFI_ALLOCATE_ANY_PAGES, sz, &buf) !=
EFI_SUCCESS) {
debug("EFI: ERROR: out of memory in %s\n", __func__);
return NULL;
}
memset(buf, 0, sz);
return buf;
}
/*
* Iterate to next block in device-path, terminating (returning NULL)
* at /End* node.
*/
struct efi_device_path *efi_dp_next(const struct efi_device_path *dp)
{
if (dp == NULL)
return NULL;
if (dp->type == DEVICE_PATH_TYPE_END)
return NULL;
dp = ((void *)dp) + dp->length;
if (dp->type == DEVICE_PATH_TYPE_END)
return NULL;
return (struct efi_device_path *)dp;
}
/*
* Compare two device-paths, stopping when the shorter of the two hits
* an End* node. This is useful to, for example, compare a device-path
* representing a device with one representing a file on the device, or
* a device with a parent device.
*/
int efi_dp_match(const struct efi_device_path *a,
const struct efi_device_path *b)
{
while (1) {
int ret;
ret = memcmp(&a->length, &b->length, sizeof(a->length));
if (ret)
return ret;
ret = memcmp(a, b, a->length);
if (ret)
return ret;
a = efi_dp_next(a);
b = efi_dp_next(b);
if (!a || !b)
return 0;
}
}
/*
* We can have device paths that start with a USB WWID or a USB Class node,
* and a few other cases which don't encode the full device path with bus
* hierarchy:
*
* - MESSAGING:USB_WWID
* - MESSAGING:USB_CLASS
* - MEDIA:FILE_PATH
* - MEDIA:HARD_DRIVE
* - MESSAGING:URI
*
* See UEFI spec (section 3.1.2, about short-form device-paths)
*/
static struct efi_device_path *shorten_path(struct efi_device_path *dp)
{
while (dp) {
/*
* TODO: Add MESSAGING:USB_WWID and MESSAGING:URI..
* in practice fallback.efi just uses MEDIA:HARD_DRIVE
* so not sure when we would see these other cases.
*/
if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_CLASS) ||
EFI_DP_TYPE(dp, MEDIA_DEVICE, HARD_DRIVE_PATH) ||
EFI_DP_TYPE(dp, MEDIA_DEVICE, FILE_PATH))
return dp;
dp = efi_dp_next(dp);
}
return dp;
}
static struct efi_object *find_obj(struct efi_device_path *dp, bool short_path,
struct efi_device_path **rem)
{
struct efi_object *efiobj;
efi_uintn_t dp_size = efi_dp_instance_size(dp);
list_for_each_entry(efiobj, &efi_obj_list, link) {
struct efi_handler *handler;
struct efi_device_path *obj_dp;
efi_status_t ret;
ret = efi_search_protocol(efiobj,
&efi_guid_device_path, &handler);
if (ret != EFI_SUCCESS)
continue;
obj_dp = handler->protocol_interface;
do {
if (efi_dp_match(dp, obj_dp) == 0) {
if (rem) {
/*
* Allow partial matches, but inform
* the caller.
*/
*rem = ((void *)dp) +
efi_dp_instance_size(obj_dp);
return efiobj;
} else {
/* Only return on exact matches */
if (efi_dp_instance_size(obj_dp) ==
dp_size)
return efiobj;
}
}
obj_dp = shorten_path(efi_dp_next(obj_dp));
} while (short_path && obj_dp);
}
return NULL;
}
/*
* Find an efiobj from device-path, if 'rem' is not NULL, returns the
* remaining part of the device path after the matched object.
*/
struct efi_object *efi_dp_find_obj(struct efi_device_path *dp,
struct efi_device_path **rem)
{
struct efi_object *efiobj;
/* Search for an exact match first */
efiobj = find_obj(dp, false, NULL);
/* Then for a fuzzy match */
if (!efiobj)
efiobj = find_obj(dp, false, rem);
/* And now for a fuzzy short match */
if (!efiobj)
efiobj = find_obj(dp, true, rem);
return efiobj;
}
/*
* Determine the last device path node that is not the end node.
*
* @dp device path
* @return last node before the end node if it exists
* otherwise NULL
*/
const struct efi_device_path *efi_dp_last_node(const struct efi_device_path *dp)
{
struct efi_device_path *ret;
if (!dp || dp->type == DEVICE_PATH_TYPE_END)
return NULL;
while (dp) {
ret = (struct efi_device_path *)dp;
dp = efi_dp_next(dp);
}
return ret;
}
/* get size of the first device path instance excluding end node */
efi_uintn_t efi_dp_instance_size(const struct efi_device_path *dp)
{
efi_uintn_t sz = 0;
if (!dp || dp->type == DEVICE_PATH_TYPE_END)
return 0;
while (dp) {
sz += dp->length;
dp = efi_dp_next(dp);
}
return sz;
}
/* get size of multi-instance device path excluding end node */
efi_uintn_t efi_dp_size(const struct efi_device_path *dp)
{
const struct efi_device_path *p = dp;
if (!p)
return 0;
while (p->type != DEVICE_PATH_TYPE_END ||
p->sub_type != DEVICE_PATH_SUB_TYPE_END)
p = (void *)p + p->length;
return (void *)p - (void *)dp;
}
/* copy multi-instance device path */
struct efi_device_path *efi_dp_dup(const struct efi_device_path *dp)
{
struct efi_device_path *ndp;
size_t sz = efi_dp_size(dp) + sizeof(END);
if (!dp)
return NULL;
ndp = dp_alloc(sz);
if (!ndp)
return NULL;
memcpy(ndp, dp, sz);
return ndp;
}
struct efi_device_path *efi_dp_append(const struct efi_device_path *dp1,
const struct efi_device_path *dp2)
{
struct efi_device_path *ret;
if (!dp1 && !dp2) {
/* return an end node */
ret = efi_dp_dup(&END);
} else if (!dp1) {
ret = efi_dp_dup(dp2);
} else if (!dp2) {
ret = efi_dp_dup(dp1);
} else {
/* both dp1 and dp2 are non-null */
unsigned sz1 = efi_dp_size(dp1);
unsigned sz2 = efi_dp_size(dp2);
void *p = dp_alloc(sz1 + sz2 + sizeof(END));
if (!p)
return NULL;
memcpy(p, dp1, sz1);
/* the end node of the second device path has to be retained */
memcpy(p + sz1, dp2, sz2 + sizeof(END));
ret = p;
}
return ret;
}
struct efi_device_path *efi_dp_append_node(const struct efi_device_path *dp,
const struct efi_device_path *node)
{
struct efi_device_path *ret;
if (!node && !dp) {
ret = efi_dp_dup(&END);
} else if (!node) {
ret = efi_dp_dup(dp);
} else if (!dp) {
size_t sz = node->length;
void *p = dp_alloc(sz + sizeof(END));
if (!p)
return NULL;
memcpy(p, node, sz);
memcpy(p + sz, &END, sizeof(END));
ret = p;
} else {
/* both dp and node are non-null */
size_t sz = efi_dp_size(dp);
void *p = dp_alloc(sz + node->length + sizeof(END));
if (!p)
return NULL;
memcpy(p, dp, sz);
memcpy(p + sz, node, node->length);
memcpy(p + sz + node->length, &END, sizeof(END));
ret = p;
}
return ret;
}
struct efi_device_path *efi_dp_create_device_node(const u8 type,
const u8 sub_type,
const u16 length)
{
struct efi_device_path *ret;
if (length < sizeof(struct efi_device_path))
return NULL;
ret = dp_alloc(length);
if (!ret)
return ret;
ret->type = type;
ret->sub_type = sub_type;
ret->length = length;
return ret;
}
struct efi_device_path *efi_dp_append_instance(
const struct efi_device_path *dp,
const struct efi_device_path *dpi)
{
size_t sz, szi;
struct efi_device_path *p, *ret;
if (!dpi)
return NULL;
if (!dp)
return efi_dp_dup(dpi);
sz = efi_dp_size(dp);
szi = efi_dp_instance_size(dpi);
p = dp_alloc(sz + szi + 2 * sizeof(END));
if (!p)
return NULL;
ret = p;
memcpy(p, dp, sz + sizeof(END));
p = (void *)p + sz;
p->sub_type = DEVICE_PATH_SUB_TYPE_INSTANCE_END;
p = (void *)p + sizeof(END);
memcpy(p, dpi, szi);
p = (void *)p + szi;
memcpy(p, &END, sizeof(END));
return ret;
}
struct efi_device_path *efi_dp_get_next_instance(struct efi_device_path **dp,
efi_uintn_t *size)
{
size_t sz;
struct efi_device_path *p;
if (size)
*size = 0;
if (!dp || !*dp)
return NULL;
sz = efi_dp_instance_size(*dp);
p = dp_alloc(sz + sizeof(END));
if (!p)
return NULL;
memcpy(p, *dp, sz + sizeof(END));
*dp = (void *)*dp + sz;
if ((*dp)->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END)
*dp = (void *)*dp + sizeof(END);
else
*dp = NULL;
if (size)
*size = sz + sizeof(END);
return p;
}
bool efi_dp_is_multi_instance(const struct efi_device_path *dp)
{
const struct efi_device_path *p = dp;
if (!p)
return false;
while (p->type != DEVICE_PATH_TYPE_END)
p = (void *)p + p->length;
return p->sub_type == DEVICE_PATH_SUB_TYPE_INSTANCE_END;
}
#ifdef CONFIG_DM
/* size of device-path not including END node for device and all parents
* up to the root device.
*/
__maybe_unused static unsigned int dp_size(struct udevice *dev)
{
if (!dev || !dev->driver)
return sizeof(ROOT);
switch (dev->driver->id) {
case UCLASS_ROOT:
case UCLASS_SIMPLE_BUS:
/* stop traversing parents at this point: */
return sizeof(ROOT);
case UCLASS_ETH:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_mac_addr);
#ifdef CONFIG_BLK
case UCLASS_BLK:
switch (dev->parent->uclass->uc_drv->id) {
#ifdef CONFIG_IDE
case UCLASS_IDE:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_atapi);
#endif
#if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
case UCLASS_SCSI:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_scsi);
#endif
#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
case UCLASS_MMC:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_sd_mmc_path);
#endif
#if defined(CONFIG_AHCI) || defined(CONFIG_SATA)
case UCLASS_AHCI:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_sata);
#endif
#if defined(CONFIG_NVME)
case UCLASS_NVME:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_nvme);
#endif
#ifdef CONFIG_SANDBOX
case UCLASS_ROOT:
/*
* Sandbox's host device will be represented
* as vendor device with extra one byte for
* device number
*/
return dp_size(dev->parent)
+ sizeof(struct efi_device_path_vendor) + 1;
#endif
#ifdef CONFIG_VIRTIO_BLK
case UCLASS_VIRTIO:
/*
* Virtio devices will be represented as a vendor
* device node with an extra byte for the device
* number.
*/
return dp_size(dev->parent)
+ sizeof(struct efi_device_path_vendor) + 1;
#endif
default:
return dp_size(dev->parent);
}
#endif
#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
case UCLASS_MMC:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_sd_mmc_path);
#endif
case UCLASS_MASS_STORAGE:
case UCLASS_USB_HUB:
return dp_size(dev->parent) +
sizeof(struct efi_device_path_usb_class);
default:
/* just skip over unknown classes: */
return dp_size(dev->parent);
}
}
/*
* Recursively build a device path.
*
* @buf pointer to the end of the device path
* @dev device
* @return pointer to the end of the device path
*/
__maybe_unused static void *dp_fill(void *buf, struct udevice *dev)
{
if (!dev || !dev->driver)
return buf;
switch (dev->driver->id) {
case UCLASS_ROOT:
case UCLASS_SIMPLE_BUS: {
/* stop traversing parents at this point: */
struct efi_device_path_vendor *vdp = buf;
*vdp = ROOT;
return &vdp[1];
}
#ifdef CONFIG_DM_ETH
case UCLASS_ETH: {
struct efi_device_path_mac_addr *dp =
dp_fill(buf, dev->parent);
struct eth_pdata *pdata = dev->platdata;
dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
dp->dp.length = sizeof(*dp);
memset(&dp->mac, 0, sizeof(dp->mac));
/* We only support IPv4 */
memcpy(&dp->mac, &pdata->enetaddr, ARP_HLEN);
/* Ethernet */
dp->if_type = 1;
return &dp[1];
}
#endif
#ifdef CONFIG_BLK
case UCLASS_BLK:
switch (dev->parent->uclass->uc_drv->id) {
#ifdef CONFIG_SANDBOX
case UCLASS_ROOT: {
/* stop traversing parents at this point: */
struct efi_device_path_vendor *dp;
struct blk_desc *desc = dev_get_uclass_platdata(dev);
dp_fill(buf, dev->parent);
dp = buf;
++dp;
dp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR;
dp->dp.length = sizeof(*dp) + 1;
memcpy(&dp->guid, &efi_guid_host_dev,
sizeof(efi_guid_t));
dp->vendor_data[0] = desc->devnum;
return &dp->vendor_data[1];
}
#endif
#ifdef CONFIG_VIRTIO_BLK
case UCLASS_VIRTIO: {
struct efi_device_path_vendor *dp;
struct blk_desc *desc = dev_get_uclass_platdata(dev);
dp_fill(buf, dev->parent);
dp = buf;
++dp;
dp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR;
dp->dp.length = sizeof(*dp) + 1;
memcpy(&dp->guid, &efi_guid_virtio_dev,
sizeof(efi_guid_t));
dp->vendor_data[0] = desc->devnum;
return &dp->vendor_data[1];
}
#endif
#ifdef CONFIG_IDE
case UCLASS_IDE: {
struct efi_device_path_atapi *dp =
dp_fill(buf, dev->parent);
struct blk_desc *desc = dev_get_uclass_platdata(dev);
dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_ATAPI;
dp->dp.length = sizeof(*dp);
dp->logical_unit_number = desc->devnum;
dp->primary_secondary = IDE_BUS(desc->devnum);
dp->slave_master = desc->devnum %
(CONFIG_SYS_IDE_MAXDEVICE /
CONFIG_SYS_IDE_MAXBUS);
return &dp[1];
}
#endif
#if defined(CONFIG_SCSI) && defined(CONFIG_DM_SCSI)
case UCLASS_SCSI: {
struct efi_device_path_scsi *dp =
dp_fill(buf, dev->parent);
struct blk_desc *desc = dev_get_uclass_platdata(dev);
dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SCSI;
dp->dp.length = sizeof(*dp);
dp->logical_unit_number = desc->lun;
dp->target_id = desc->target;
return &dp[1];
}
#endif
#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
case UCLASS_MMC: {
struct efi_device_path_sd_mmc_path *sddp =
dp_fill(buf, dev->parent);
struct blk_desc *desc = dev_get_uclass_platdata(dev);
sddp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
sddp->dp.sub_type = is_sd(desc) ?
DEVICE_PATH_SUB_TYPE_MSG_SD :
DEVICE_PATH_SUB_TYPE_MSG_MMC;
sddp->dp.length = sizeof(*sddp);
sddp->slot_number = dev->seq;
return &sddp[1];
}
#endif
#if defined(CONFIG_AHCI) || defined(CONFIG_SATA)
case UCLASS_AHCI: {
struct efi_device_path_sata *dp =
dp_fill(buf, dev->parent);
struct blk_desc *desc = dev_get_uclass_platdata(dev);
dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_SATA;
dp->dp.length = sizeof(*dp);
dp->hba_port = desc->devnum;
/* default 0xffff implies no port multiplier */
dp->port_multiplier_port = 0xffff;
dp->logical_unit_number = desc->lun;
return &dp[1];
}
#endif
#if defined(CONFIG_NVME)
case UCLASS_NVME: {
struct efi_device_path_nvme *dp =
dp_fill(buf, dev->parent);
u32 ns_id;
dp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_NVME;
dp->dp.length = sizeof(*dp);
nvme_get_namespace_id(dev, &ns_id, dp->eui64);
memcpy(&dp->ns_id, &ns_id, sizeof(ns_id));
return &dp[1];
}
#endif
default:
debug("%s(%u) %s: unhandled parent class: %s (%u)\n",
__FILE__, __LINE__, __func__,
dev->name, dev->parent->uclass->uc_drv->id);
return dp_fill(buf, dev->parent);
}
#endif
#if defined(CONFIG_DM_MMC) && defined(CONFIG_MMC)
case UCLASS_MMC: {
struct efi_device_path_sd_mmc_path *sddp =
dp_fill(buf, dev->parent);
struct mmc *mmc = mmc_get_mmc_dev(dev);
struct blk_desc *desc = mmc_get_blk_desc(mmc);
sddp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
sddp->dp.sub_type = is_sd(desc) ?
DEVICE_PATH_SUB_TYPE_MSG_SD :
DEVICE_PATH_SUB_TYPE_MSG_MMC;
sddp->dp.length = sizeof(*sddp);
sddp->slot_number = dev->seq;
return &sddp[1];
}
#endif
case UCLASS_MASS_STORAGE:
case UCLASS_USB_HUB: {
struct efi_device_path_usb_class *udp =
dp_fill(buf, dev->parent);
struct usb_device *udev = dev_get_parent_priv(dev);
struct usb_device_descriptor *desc = &udev->descriptor;
udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB_CLASS;
udp->dp.length = sizeof(*udp);
udp->vendor_id = desc->idVendor;
udp->product_id = desc->idProduct;
udp->device_class = desc->bDeviceClass;
udp->device_subclass = desc->bDeviceSubClass;
udp->device_protocol = desc->bDeviceProtocol;
return &udp[1];
}
default:
debug("%s(%u) %s: unhandled device class: %s (%u)\n",
__FILE__, __LINE__, __func__,
dev->name, dev->driver->id);
return dp_fill(buf, dev->parent);
}
}
#endif
static unsigned dp_part_size(struct blk_desc *desc, int part)
{
unsigned dpsize;
#ifdef CONFIG_BLK
{
struct udevice *dev;
int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
if (ret)
dev = desc->bdev->parent;
dpsize = dp_size(dev);
}
#else
dpsize = sizeof(ROOT) + sizeof(struct efi_device_path_usb);
#endif
if (part == 0) /* the actual disk, not a partition */
return dpsize;
if (desc->part_type == PART_TYPE_ISO)
dpsize += sizeof(struct efi_device_path_cdrom_path);
else
dpsize += sizeof(struct efi_device_path_hard_drive_path);
return dpsize;
}
/*
* Create a device node for a block device partition.
*
* @buf buffer to which the device path is written
* @desc block device descriptor
* @part partition number, 0 identifies a block device
*/
static void *dp_part_node(void *buf, struct blk_desc *desc, int part)
{
struct disk_partition info;
part_get_info(desc, part, &info);
if (desc->part_type == PART_TYPE_ISO) {
struct efi_device_path_cdrom_path *cddp = buf;
cddp->boot_entry = part;
cddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
cddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CDROM_PATH;
cddp->dp.length = sizeof(*cddp);
cddp->partition_start = info.start;
cddp->partition_size = info.size;
buf = &cddp[1];
} else {
struct efi_device_path_hard_drive_path *hddp = buf;
hddp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
hddp->dp.sub_type = DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH;
hddp->dp.length = sizeof(*hddp);
hddp->partition_number = part;
hddp->partition_start = info.start;
hddp->partition_end = info.size;
if (desc->part_type == PART_TYPE_EFI)
hddp->partmap_type = 2;
else
hddp->partmap_type = 1;
switch (desc->sig_type) {
case SIG_TYPE_NONE:
default:
hddp->signature_type = 0;
memset(hddp->partition_signature, 0,
sizeof(hddp->partition_signature));
break;
case SIG_TYPE_MBR:
hddp->signature_type = 1;
memset(hddp->partition_signature, 0,
sizeof(hddp->partition_signature));
memcpy(hddp->partition_signature, &desc->mbr_sig,
sizeof(desc->mbr_sig));
break;
case SIG_TYPE_GUID:
hddp->signature_type = 2;
memcpy(hddp->partition_signature, &desc->guid_sig,
sizeof(hddp->partition_signature));
break;
}
buf = &hddp[1];
}
return buf;
}
/*
* Create a device path for a block device or one of its partitions.
*
* @buf buffer to which the device path is written
* @desc block device descriptor
* @part partition number, 0 identifies a block device
*/
static void *dp_part_fill(void *buf, struct blk_desc *desc, int part)
{
#ifdef CONFIG_BLK
{
struct udevice *dev;
int ret = blk_find_device(desc->if_type, desc->devnum, &dev);
if (ret)
dev = desc->bdev->parent;
buf = dp_fill(buf, dev);
}
#else
/*
* We *could* make a more accurate path, by looking at if_type
* and handling all the different cases like we do for non-
* legacy (i.e. CONFIG_BLK=y) case. But most important thing
* is just to have a unique device-path for if_type+devnum.
* So map things to a fictitious USB device.
*/
struct efi_device_path_usb *udp;
memcpy(buf, &ROOT, sizeof(ROOT));
buf += sizeof(ROOT);
udp = buf;
udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB;
udp->dp.length = sizeof(*udp);
udp->parent_port_number = desc->if_type;
udp->usb_interface = desc->devnum;
buf = &udp[1];
#endif
if (part == 0) /* the actual disk, not a partition */
return buf;
return dp_part_node(buf, desc, part);
}
/* Construct a device-path from a partition on a block device: */
struct efi_device_path *efi_dp_from_part(struct blk_desc *desc, int part)
{
void *buf, *start;
start = buf = dp_alloc(dp_part_size(desc, part) + sizeof(END));
if (!buf)
return NULL;
buf = dp_part_fill(buf, desc, part);
*((struct efi_device_path *)buf) = END;
return start;
}
/*
* Create a device node for a block device partition.
*
* @buf buffer to which the device path is written
* @desc block device descriptor
* @part partition number, 0 identifies a block device
*/
struct efi_device_path *efi_dp_part_node(struct blk_desc *desc, int part)
{
efi_uintn_t dpsize;
void *buf;
if (desc->part_type == PART_TYPE_ISO)
dpsize = sizeof(struct efi_device_path_cdrom_path);
else
dpsize = sizeof(struct efi_device_path_hard_drive_path);
buf = dp_alloc(dpsize);
dp_part_node(buf, desc, part);
return buf;
}
/**
* path_to_uefi() - convert UTF-8 path to an UEFI style path
*
* Convert UTF-8 path to a UEFI style path (i.e. with backslashes as path
* separators and UTF-16).
*
* @src: source buffer
* @uefi: target buffer, possibly unaligned
*/
static void path_to_uefi(void *uefi, const char *src)
{
u16 *pos = uefi;
/*
* efi_set_bootdev() calls this routine indirectly before the UEFI
* subsystem is initialized. So we cannot assume unaligned access to be
* enabled.
*/
allow_unaligned();
while (*src) {
s32 code = utf8_get(&src);
if (code < 0)
code = '?';
else if (code == '/')
code = '\\';
utf16_put(code, &pos);
}
*pos = 0;
}
/*
* If desc is NULL, this creates a path with only the file component,
* otherwise it creates a full path with both device and file components
*/
struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
const char *path)
{
struct efi_device_path_file_path *fp;
void *buf, *start;
size_t dpsize = 0, fpsize;
if (desc)
dpsize = dp_part_size(desc, part);
fpsize = sizeof(struct efi_device_path) +
2 * (utf8_utf16_strlen(path) + 1);
if (fpsize > U16_MAX)
return NULL;
dpsize += fpsize;
start = buf = dp_alloc(dpsize + sizeof(END));
if (!buf)
return NULL;
if (desc)
buf = dp_part_fill(buf, desc, part);
/* add file-path: */
fp = buf;
fp->dp.type = DEVICE_PATH_TYPE_MEDIA_DEVICE;
fp->dp.sub_type = DEVICE_PATH_SUB_TYPE_FILE_PATH;
fp->dp.length = (u16)fpsize;
path_to_uefi(fp->str, path);
buf += fpsize;
*((struct efi_device_path *)buf) = END;
return start;
}
#ifdef CONFIG_NET
struct efi_device_path *efi_dp_from_eth(void)
{
#ifndef CONFIG_DM_ETH
struct efi_device_path_mac_addr *ndp;
#endif
void *buf, *start;
unsigned dpsize = 0;
assert(eth_get_dev());
#ifdef CONFIG_DM_ETH
dpsize += dp_size(eth_get_dev());
#else
dpsize += sizeof(ROOT);
dpsize += sizeof(*ndp);
#endif
start = buf = dp_alloc(dpsize + sizeof(END));
if (!buf)
return NULL;
#ifdef CONFIG_DM_ETH
buf = dp_fill(buf, eth_get_dev());
#else
memcpy(buf, &ROOT, sizeof(ROOT));
buf += sizeof(ROOT);
ndp = buf;
ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
ndp->dp.length = sizeof(*ndp);
ndp->if_type = 1; /* Ethernet */
memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
buf = &ndp[1];
#endif
*((struct efi_device_path *)buf) = END;
return start;
}
#endif
/* Construct a device-path for memory-mapped image */
struct efi_device_path *efi_dp_from_mem(uint32_t memory_type,
uint64_t start_address,
uint64_t end_address)
{
struct efi_device_path_memory *mdp;
void *buf, *start;
start = buf = dp_alloc(sizeof(*mdp) + sizeof(END));
if (!buf)
return NULL;
mdp = buf;
mdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE;
mdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MEMORY;
mdp->dp.length = sizeof(*mdp);
mdp->memory_type = memory_type;
mdp->start_address = start_address;
mdp->end_address = end_address;
buf = &mdp[1];
*((struct efi_device_path *)buf) = END;
return start;
}
/**
* efi_dp_split_file_path() - split of relative file path from device path
*
* Given a device path indicating a file on a device, separate the device
* path in two: the device path of the actual device and the file path
* relative to this device.
*
* @full_path: device path including device and file path
* @device_path: path of the device
* @file_path: relative path of the file or NULL if there is none
* Return: status code
*/
efi_status_t efi_dp_split_file_path(struct efi_device_path *full_path,
struct efi_device_path **device_path,
struct efi_device_path **file_path)
{
struct efi_device_path *p, *dp, *fp = NULL;
*device_path = NULL;
*file_path = NULL;
dp = efi_dp_dup(full_path);
if (!dp)
return EFI_OUT_OF_RESOURCES;
p = dp;
while (!EFI_DP_TYPE(p, MEDIA_DEVICE, FILE_PATH)) {
p = efi_dp_next(p);
if (!p)
goto out;
}
fp = efi_dp_dup(p);
if (!fp)
return EFI_OUT_OF_RESOURCES;
p->type = DEVICE_PATH_TYPE_END;
p->sub_type = DEVICE_PATH_SUB_TYPE_END;
p->length = sizeof(*p);
out:
*device_path = dp;
*file_path = fp;
return EFI_SUCCESS;
}
/**
* efi_dp_from_name() - convert U-Boot device and file path to device path
*
* @dev: U-Boot device, e.g. 'mmc'
* @devnr: U-Boot device number, e.g. 1 for 'mmc:1'
* @path: file path relative to U-Boot device, may be NULL
* @device: pointer to receive device path of the device
* @file: pointer to receive device path for the file
* Return: status code
*/
efi_status_t efi_dp_from_name(const char *dev, const char *devnr,
const char *path,
struct efi_device_path **device,
struct efi_device_path **file)
{
int is_net;
struct blk_desc *desc = NULL;
struct disk_partition fs_partition;
int part = 0;
char filename[32] = { 0 }; /* dp->str is u16[32] long */
char *s;
if (path && !file)
return EFI_INVALID_PARAMETER;
is_net = !strcmp(dev, "Net");
if (!is_net) {
part = blk_get_device_part_str(dev, devnr, &desc, &fs_partition,
1);
if (part < 0 || !desc)
return EFI_INVALID_PARAMETER;
if (device)
*device = efi_dp_from_part(desc, part);
} else {
#ifdef CONFIG_NET
if (device)
*device = efi_dp_from_eth();
#endif
}
if (!path)
return EFI_SUCCESS;
snprintf(filename, sizeof(filename), "%s", path);
/* DOS style file path: */
s = filename;
while ((s = strchr(s, '/')))
*s++ = '\\';
*file = efi_dp_from_file(is_net ? NULL : desc, part, filename);
if (!*file)
return EFI_INVALID_PARAMETER;
return EFI_SUCCESS;
}
/**
* efi_dp_check_length() - check length of a device path
*
* @dp: pointer to device path
* @maxlen: maximum length of the device path
* Return:
* * length of the device path if it is less or equal @maxlen
* * -1 if the device path is longer then @maxlen
* * -1 if a device path node has a length of less than 4
* * -EINVAL if maxlen exceeds SSIZE_MAX
*/
ssize_t efi_dp_check_length(const struct efi_device_path *dp,
const size_t maxlen)
{
ssize_t ret = 0;
u16 len;
if (maxlen > SSIZE_MAX)
return -EINVAL;
for (;;) {
len = dp->length;
if (len < 4)
return -1;
ret += len;
if (ret > maxlen)
return -1;
if (dp->type == DEVICE_PATH_TYPE_END &&
dp->sub_type == DEVICE_PATH_SUB_TYPE_END)
return ret;
dp = (const struct efi_device_path *)((const u8 *)dp + len);
}
}