diff options
Diffstat (limited to 'lib/efi_loader/efi_device_path.c')
| -rw-r--r-- | lib/efi_loader/efi_device_path.c | 1193 |
1 files changed, 1193 insertions, 0 deletions
diff --git a/lib/efi_loader/efi_device_path.c b/lib/efi_loader/efi_device_path.c new file mode 100644 index 00000000000..aec224d8466 --- /dev/null +++ b/lib/efi_loader/efi_device_path.c @@ -0,0 +1,1193 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * EFI device path from u-boot device-model mapping + * + * (C) Copyright 2017 Rob Clark + */ + +#define LOG_CATEGORY LOGC_EFI + +#include <blk.h> +#include <dm.h> +#include <dm/root.h> +#include <log.h> +#include <net.h> +#include <usb.h> +#include <mmc.h> +#include <nvme.h> +#include <efi_loader.h> +#include <part.h> +#include <uuid.h> +#include <asm-generic/unaligned.h> +#include <linux/compat.h> /* U16_MAX */ + +/* template END node: */ +const struct efi_device_path END = { + .type = DEVICE_PATH_TYPE_END, + .sub_type = DEVICE_PATH_SUB_TYPE_END, + .length = sizeof(END), +}; + +#if 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 + +/* + * 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; + } +} + +/** + * efi_dp_shorten() - shorten device-path + * + * When creating a short boot option we want to use a device-path that is + * independent of the location where the block device is plugged in. + * + * UsbWwi() nodes contain a serial number, hard drive paths a partition + * UUID. Both should be unique. + * + * See UEFI spec, section 3.1.2 for "short-form device path". + * + * @dp: original device-path + * Return: shortened device-path or NULL + */ +struct efi_device_path *efi_dp_shorten(struct efi_device_path *dp) +{ + while (dp) { + if (EFI_DP_TYPE(dp, MESSAGING_DEVICE, MSG_USB_WWI) || + 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; +} + +/** + * find_handle() - find handle by device path and installed protocol + * + * If @rem is provided, the handle with the longest partial match is returned. + * + * @dp: device path to search + * @guid: GUID of protocol that must be installed on path or NULL + * @short_path: use short form device path for matching + * @rem: pointer to receive remaining device path + * Return: matching handle + */ +static efi_handle_t find_handle(struct efi_device_path *dp, + const efi_guid_t *guid, bool short_path, + struct efi_device_path **rem) +{ + efi_handle_t handle, best_handle = NULL; + efi_uintn_t len, best_len = 0; + + len = efi_dp_instance_size(dp); + + list_for_each_entry(handle, &efi_obj_list, link) { + struct efi_handler *handler; + struct efi_device_path *dp_current; + efi_uintn_t len_current; + efi_status_t ret; + + if (guid) { + ret = efi_search_protocol(handle, guid, &handler); + if (ret != EFI_SUCCESS) + continue; + } + ret = efi_search_protocol(handle, &efi_guid_device_path, + &handler); + if (ret != EFI_SUCCESS) + continue; + dp_current = handler->protocol_interface; + if (short_path) { + dp_current = efi_dp_shorten(dp_current); + if (!dp_current) + continue; + } + len_current = efi_dp_instance_size(dp_current); + if (rem) { + if (len_current > len) + continue; + } else { + if (len_current != len) + continue; + } + if (memcmp(dp_current, dp, len_current)) + continue; + if (!rem) + return handle; + if (len_current > best_len) { + best_len = len_current; + best_handle = handle; + *rem = (void*)((u8 *)dp + len_current); + } + } + return best_handle; +} + +/** + * efi_dp_find_obj() - find handle by device path + * + * If @rem is provided, the handle with the longest partial match is returned. + * + * @dp: device path to search + * @guid: GUID of protocol that must be installed on path or NULL + * @rem: pointer to receive remaining device path + * Return: matching handle + */ +efi_handle_t efi_dp_find_obj(struct efi_device_path *dp, + const efi_guid_t *guid, + struct efi_device_path **rem) +{ + efi_handle_t handle; + + handle = find_handle(dp, guid, false, rem); + if (!handle) + /* Match short form device path */ + handle = find_handle(dp, guid, true, rem); + + return handle; +} + +/* + * 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 = efi_alloc(sz); + if (!ndp) + return NULL; + memcpy(ndp, dp, sz); + + return ndp; +} + +/** + * efi_dp_concat() - Concatenate two device paths and add and terminate them + * with an end node. + * + * @dp1: First device path + * @dp2: Second device path + * @split_end_node: If true the two device paths will be concatenated and + * separated by an end node (DEVICE_PATH_SUB_TYPE_END). + * If false the second device path will be concatenated to the + * first one as-is. + * + * Return: + * concatenated device path or NULL. Caller must free the returned value + */ +struct +efi_device_path *efi_dp_concat(const struct efi_device_path *dp1, + const struct efi_device_path *dp2, + bool split_end_node) +{ + struct efi_device_path *ret; + size_t end_size; + + 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; + + if (split_end_node) + end_size = 2 * sizeof(END); + else + end_size = sizeof(END); + p = efi_alloc(sz1 + sz2 + end_size); + if (!p) + return NULL; + ret = p; + memcpy(p, dp1, sz1); + p += sz1; + + if (split_end_node) { + memcpy(p, &END, sizeof(END)); + p += sizeof(END); + } + + /* the end node of the second device path has to be retained */ + memcpy(p, dp2, sz2); + p += sz2; + memcpy(p, &END, sizeof(END)); + } + + 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 = efi_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 = efi_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 = efi_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 = efi_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 = efi_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; +} + +/* 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(struct efi_device_path_udevice); + + switch (device_get_uclass_id(dev)) { + case UCLASS_ROOT: + /* stop traversing parents at this point: */ + return sizeof(struct efi_device_path_udevice); + case UCLASS_ETH: + return dp_size(dev->parent) + + sizeof(struct efi_device_path_mac_addr); + 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) + case UCLASS_SCSI: + return dp_size(dev->parent) + + sizeof(struct efi_device_path_scsi); +#endif +#if 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_USB + case UCLASS_MASS_STORAGE: + return dp_size(dev->parent) + + sizeof(struct efi_device_path_controller); +#endif + default: + /* UCLASS_BLKMAP, UCLASS_HOST, UCLASS_VIRTIO */ + return dp_size(dev->parent) + + sizeof(struct efi_device_path_udevice); + } +#if 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); + default: + return dp_size(dev->parent) + + sizeof(struct efi_device_path_udevice); + } +} + +/* + * 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) +{ + enum uclass_id uclass_id; + + if (!dev || !dev->driver) + return buf; + + uclass_id = device_get_uclass_id(dev); + if (uclass_id != UCLASS_ROOT) + buf = dp_fill(buf, dev->parent); + + switch (uclass_id) { +#ifdef CONFIG_NETDEVICES + case UCLASS_ETH: { + struct efi_device_path_mac_addr *dp = buf; + struct eth_pdata *pdata = dev_get_plat(dev); + + 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 + case UCLASS_BLK: + switch (device_get_uclass_id(dev->parent)) { +#ifdef CONFIG_IDE + case UCLASS_IDE: { + struct efi_device_path_atapi *dp = buf; + struct blk_desc *desc = dev_get_uclass_plat(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) + case UCLASS_SCSI: { + struct efi_device_path_scsi *dp = buf; + struct blk_desc *desc = dev_get_uclass_plat(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_MMC) + case UCLASS_MMC: { + struct efi_device_path_sd_mmc_path *sddp = buf; + struct blk_desc *desc = dev_get_uclass_plat(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(dev); + return &sddp[1]; + } +#endif +#if defined(CONFIG_AHCI) || defined(CONFIG_SATA) + case UCLASS_AHCI: { + struct efi_device_path_sata *dp = buf; + struct blk_desc *desc = dev_get_uclass_plat(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 = buf; + 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 +#if defined(CONFIG_USB) + case UCLASS_MASS_STORAGE: { + struct blk_desc *desc = dev_get_uclass_plat(dev); + struct efi_device_path_controller *dp = buf; + + dp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE; + dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_CONTROLLER; + dp->dp.length = sizeof(*dp); + dp->controller_number = desc->lun; + return &dp[1]; + } +#endif + default: { + /* UCLASS_BLKMAP, UCLASS_HOST, UCLASS_VIRTIO */ + struct efi_device_path_udevice *dp = buf; + struct blk_desc *desc = dev_get_uclass_plat(dev); + + dp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE; + dp->dp.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR; + dp->dp.length = sizeof(*dp); + memcpy(&dp->guid, &efi_u_boot_guid, + sizeof(efi_guid_t)); + dp->uclass_id = (UCLASS_BLK & 0xffff) | + (desc->uclass_id << 16); + dp->dev_number = desc->devnum; + + return &dp[1]; + } + } +#if defined(CONFIG_MMC) + case UCLASS_MMC: { + struct efi_device_path_sd_mmc_path *sddp = buf; + 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(dev); + + return &sddp[1]; + } +#endif + case UCLASS_MASS_STORAGE: + case UCLASS_USB_HUB: { + struct efi_device_path_usb *udp = buf; + + switch (device_get_uclass_id(dev->parent)) { + case UCLASS_USB_HUB: { + struct usb_device *udev = dev_get_parent_priv(dev); + + udp->parent_port_number = udev->portnr; + break; + } + default: + udp->parent_port_number = 0; + } + udp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE; + udp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_USB; + udp->dp.length = sizeof(*udp); + udp->usb_interface = 0; + + return &udp[1]; + } + default: { + struct efi_device_path_udevice *vdp = buf; + + vdp->dp.type = DEVICE_PATH_TYPE_HARDWARE_DEVICE; + vdp->dp.sub_type = DEVICE_PATH_SUB_TYPE_VENDOR; + vdp->dp.length = sizeof(*vdp); + memcpy(&vdp->guid, &efi_u_boot_guid, sizeof(efi_guid_t)); + vdp->uclass_id = uclass_id; + vdp->dev_number = dev->seq_; + + return &vdp[1]; + } + } +} + +static unsigned dp_part_size(struct blk_desc *desc, int part) +{ + unsigned dpsize; + struct udevice *dev = desc->bdev; + + dpsize = dp_size(dev); + + 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 + * + * Return: pointer to position after the node + */ +static void *dp_part_node(void *buf, struct blk_desc *desc, int part) +{ + struct disk_partition info; + int ret; + + ret = part_get_info(desc, part, &info); + if (ret < 0) + return buf; + + 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; +#if CONFIG_IS_ENABLED(PARTITION_UUIDS) + /* info.uuid exists only with PARTITION_UUIDS */ + if (uuid_str_to_bin(info.uuid, + hddp->partition_signature, + UUID_STR_FORMAT_GUID)) { + log_warning( + "Partition %d: invalid GUID %s\n", + part, info.uuid); + } +#endif + 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) +{ + struct udevice *dev = desc->bdev; + + buf = dp_fill(buf, dev); + + 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 = efi_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 = efi_alloc(dpsize); + + if (buf) + 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; +} + +/** + * efi_dp_from_file() - append file path node to device path. + * + * @dp: device path or NULL + * @path: file path or NULL + * Return: device path or NULL in case of an error + */ +struct efi_device_path *efi_dp_from_file(const struct efi_device_path *dp, + const char *path) +{ + struct efi_device_path_file_path *fp; + void *buf, *pos; + size_t dpsize, fpsize; + + dpsize = efi_dp_size(dp); + fpsize = sizeof(struct efi_device_path) + + 2 * (utf8_utf16_strlen(path) + 1); + if (fpsize > U16_MAX) + return NULL; + + buf = efi_alloc(dpsize + fpsize + sizeof(END)); + if (!buf) + return NULL; + + memcpy(buf, dp, dpsize); + pos = buf + dpsize; + + /* add file-path: */ + if (*path) { + fp = pos; + 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); + pos += fpsize; + } + + memcpy(pos, &END, sizeof(END)); + + return buf; +} + +struct efi_device_path *efi_dp_from_uart(void) +{ + void *buf, *pos; + struct efi_device_path_uart *uart; + size_t dpsize = dp_size(dm_root()) + sizeof(*uart) + sizeof(END); + + buf = efi_alloc(dpsize); + if (!buf) + return NULL; + pos = dp_fill(buf, dm_root()); + uart = pos; + uart->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE; + uart->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_UART; + uart->dp.length = sizeof(*uart); + pos += sizeof(*uart); + memcpy(pos, &END, sizeof(END)); + + return buf; +} + +struct efi_device_path __maybe_unused *efi_dp_from_eth(void) +{ + void *buf, *start; + unsigned dpsize = 0; + + assert(eth_get_dev()); + + dpsize += dp_size(eth_get_dev()); + + start = buf = efi_alloc(dpsize + sizeof(END)); + if (!buf) + return NULL; + + buf = dp_fill(buf, eth_get_dev()); + + *((struct efi_device_path *)buf) = END; + + return start; +} + +/* 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 = efi_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) +{ + struct blk_desc *desc = NULL; + struct efi_device_path *dp; + struct disk_partition fs_partition; + size_t image_size; + void *image_addr; + int part = 0; + + if (path && !file) + return EFI_INVALID_PARAMETER; + + if (IS_ENABLED(CONFIG_EFI_BINARY_EXEC) && + (!strcmp(dev, "Mem") || !strcmp(dev, "hostfs"))) { + /* loadm command and semihosting */ + efi_get_image_parameters(&image_addr, &image_size); + + dp = efi_dp_from_mem(EFI_RESERVED_MEMORY_TYPE, + (uintptr_t)image_addr, image_size); + } else if (IS_ENABLED(CONFIG_NETDEVICES) && !strcmp(dev, "Net")) { + dp = efi_dp_from_eth(); + } else if (!strcmp(dev, "Uart")) { + dp = efi_dp_from_uart(); + } else { + part = blk_get_device_part_str(dev, devnr, &desc, &fs_partition, + 1); + if (part < 0 || !desc) + return EFI_INVALID_PARAMETER; + + dp = efi_dp_from_part(desc, part); + } + if (device) + *device = dp; + + if (!path) + return EFI_SUCCESS; + + *file = efi_dp_from_file(dp, path); + if (!*file) + return EFI_OUT_OF_RESOURCES; + + 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); + } +} + +/** + * efi_dp_from_lo() - Get the instance of a VenMedia node in a + * multi-instance device path that matches + * a specific GUID. This kind of device paths + * is found in Boot#### options describing an + * initrd location + * + * @lo: EFI_LOAD_OPTION containing a valid device path + * @guid: guid to search for + * + * Return: + * device path including the VenMedia node or NULL. + * Caller must free the returned value. + */ +struct +efi_device_path *efi_dp_from_lo(struct efi_load_option *lo, + const efi_guid_t *guid) +{ + struct efi_device_path *fp = lo->file_path; + struct efi_device_path_vendor *vendor; + int lo_len = lo->file_path_length; + + for (; lo_len >= sizeof(struct efi_device_path); + lo_len -= fp->length, fp = (void *)fp + fp->length) { + if (lo_len < 0 || efi_dp_check_length(fp, lo_len) < 0) + break; + if (fp->type != DEVICE_PATH_TYPE_MEDIA_DEVICE || + fp->sub_type != DEVICE_PATH_SUB_TYPE_VENDOR_PATH) + continue; + + vendor = (struct efi_device_path_vendor *)fp; + if (!guidcmp(&vendor->guid, guid)) + return efi_dp_dup(efi_dp_next(fp)); + } + log_debug("VenMedia(%pUl) not found in %ls\n", &guid, lo->label); + + return NULL; +} + +/** + * search_gpt_dp_node() - search gpt device path node + * + * @device_path: device path + * + * Return: pointer to the gpt device path node + */ +struct efi_device_path *search_gpt_dp_node(struct efi_device_path *device_path) +{ + struct efi_device_path *dp = device_path; + + while (dp) { + if (dp->type == DEVICE_PATH_TYPE_MEDIA_DEVICE && + dp->sub_type == DEVICE_PATH_SUB_TYPE_HARD_DRIVE_PATH) { + struct efi_device_path_hard_drive_path *hd_dp = + (struct efi_device_path_hard_drive_path *)dp; + + if (hd_dp->partmap_type == PART_FORMAT_GPT && + hd_dp->signature_type == SIG_TYPE_GUID) + return dp; + } + dp = efi_dp_next(dp); + } + + return NULL; +} |