[thirdparty/systemd.git] / src / shared / efivars.c

/***
  This file is part of systemd.

  Copyright 2013 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>

#include "sd-id128.h"

#include "alloc-util.h"
#include "dirent-util.h"
#include "efivars.h"
#include "fd-util.h"
#include "io-util.h"
#include "macro.h"
#include "parse-util.h"
#include "stdio-util.h"
#include "time-util.h"
#include "utf8.h"
#include "util.h"
#include "virt.h"

#if ENABLE_EFI

#define LOAD_OPTION_ACTIVE            0x00000001
#define MEDIA_DEVICE_PATH                   0x04
#define MEDIA_HARDDRIVE_DP                  0x01
#define MEDIA_FILEPATH_DP                   0x04
#define SIGNATURE_TYPE_GUID                 0x02
#define MBR_TYPE_EFI_PARTITION_TABLE_HEADER 0x02
#define END_DEVICE_PATH_TYPE                0x7f
#define END_ENTIRE_DEVICE_PATH_SUBTYPE      0xff
#define EFI_OS_INDICATIONS_BOOT_TO_FW_UI    0x0000000000000001

struct boot_option {
        uint32_t attr;
        uint16_t path_len;
        uint16_t title[];
} _packed_;

struct drive_path {
        uint32_t part_nr;
        uint64_t part_start;
        uint64_t part_size;
        char signature[16];
        uint8_t mbr_type;
        uint8_t signature_type;
} _packed_;

struct device_path {
        uint8_t type;
        uint8_t sub_type;
        uint16_t length;
        union {
                uint16_t path[0];
                struct drive_path drive;
        };
} _packed_;

bool is_efi_boot(void) {
        return access("/sys/firmware/efi", F_OK) >= 0;
}

static int read_flag(const char *varname) {
        int r;
        _cleanup_free_ void *v = NULL;
        size_t s;
        uint8_t b;

        r = efi_get_variable(EFI_VENDOR_GLOBAL, varname, NULL, &v, &s);
        if (r < 0)
                return r;

        if (s != 1)
                return -EINVAL;

        b = *(uint8_t *)v;
        r = b > 0;
        return r;
}

bool is_efi_secure_boot(void) {
        return read_flag("SecureBoot") > 0;
}

bool is_efi_secure_boot_setup_mode(void) {
        return read_flag("SetupMode") > 0;
}

int efi_reboot_to_firmware_supported(void) {
        int r;
        size_t s;
        uint64_t b;
        _cleanup_free_ void *v = NULL;

        if (!is_efi_boot() || detect_container() > 0)
                return -EOPNOTSUPP;

        r = efi_get_variable(EFI_VENDOR_GLOBAL, "OsIndicationsSupported", NULL, &v, &s);
        if (r < 0)
                return r;
        else if (s != sizeof(uint64_t))
                return -EINVAL;

        b = *(uint64_t *)v;
        b &= EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
        return b > 0 ? 0 : -EOPNOTSUPP;
}

static int get_os_indications(uint64_t *os_indication) {
        int r;
        size_t s;
        _cleanup_free_ void *v = NULL;

        r = efi_reboot_to_firmware_supported();
        if (r < 0)
                return r;

        r = efi_get_variable(EFI_VENDOR_GLOBAL, "OsIndications", NULL, &v, &s);
        if (r == -ENOENT) {
                /* Some firmware implementations that do support
                 * OsIndications and report that with
                 * OsIndicationsSupported will remove the
                 * OsIndications variable when it is unset. Let's
                 * pretend it's 0 then, to hide this implementation
                 * detail. Note that this call will return -ENOENT
                 * then only if the support for OsIndications is
                 * missing entirely, as determined by
                 * efi_reboot_to_firmware_supported() above. */
                *os_indication = 0;
                return 0;
        } else if (r < 0)
                return r;
        else if (s != sizeof(uint64_t))
                return -EINVAL;

        *os_indication = *(uint64_t *)v;
        return 0;
}

int efi_get_reboot_to_firmware(void) {
        int r;
        uint64_t b;

        r = get_os_indications(&b);
        if (r < 0)
                return r;

        return !!(b & EFI_OS_INDICATIONS_BOOT_TO_FW_UI);
}

int efi_set_reboot_to_firmware(bool value) {
        int r;
        uint64_t b, b_new;

        r = get_os_indications(&b);
        if (r < 0)
                return r;

        if (value)
                b_new = b | EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
        else
                b_new = b & ~EFI_OS_INDICATIONS_BOOT_TO_FW_UI;

        /* Avoid writing to efi vars store if we can due to firmware bugs. */
        if (b != b_new)
                return efi_set_variable(EFI_VENDOR_GLOBAL, "OsIndications", &b_new, sizeof(uint64_t));

        return 0;
}

int efi_get_variable(
                sd_id128_t vendor,
                const char *name,
                uint32_t *attribute,
                void **value,
                size_t *size) {

        _cleanup_close_ int fd = -1;
        _cleanup_free_ char *p = NULL;
        uint32_t a;
        ssize_t n;
        struct stat st;
        _cleanup_free_ void *buf = NULL;

        assert(name);
        assert(value);
        assert(size);

        if (asprintf(&p,
                     "/sys/firmware/efi/efivars/%s-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                     name, SD_ID128_FORMAT_VAL(vendor)) < 0)
                return -ENOMEM;

        fd = open(p, O_RDONLY|O_NOCTTY|O_CLOEXEC);
        if (fd < 0)
                return -errno;

        if (fstat(fd, &st) < 0)
                return -errno;
        if (st.st_size < 4)
                return -EIO;
        if (st.st_size > 4*1024*1024 + 4)
                return -E2BIG;

        n = read(fd, &a, sizeof(a));
        if (n < 0)
                return -errno;
        if (n != sizeof(a))
                return -EIO;

        buf = malloc(st.st_size - 4 + 2);
        if (!buf)
                return -ENOMEM;

        n = read(fd, buf, (size_t) st.st_size - 4);
        if (n < 0)
                return -errno;
        if (n != (ssize_t) st.st_size - 4)
                return -EIO;

        /* Always NUL terminate (2 bytes, to protect UTF-16) */
        ((char*) buf)[st.st_size - 4] = 0;
        ((char*) buf)[st.st_size - 4 + 1] = 0;

        *value = buf;
        buf = NULL;
        *size = (size_t) st.st_size - 4;

        if (attribute)
                *attribute = a;

        return 0;
}

int efi_set_variable(
                sd_id128_t vendor,
                const char *name,
                const void *value,
                size_t size) {

        struct var {
                uint32_t attr;
                char buf[];
        } _packed_ * _cleanup_free_ buf = NULL;
        _cleanup_free_ char *p = NULL;
        _cleanup_close_ int fd = -1;

        assert(name);
        assert(value || size == 0);

        if (asprintf(&p,
                     "/sys/firmware/efi/efivars/%s-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                     name, SD_ID128_FORMAT_VAL(vendor)) < 0)
                return -ENOMEM;

        if (size == 0) {
                if (unlink(p) < 0)
                        return -errno;
                return 0;
        }

        fd = open(p, O_WRONLY|O_CREAT|O_NOCTTY|O_CLOEXEC, 0644);
        if (fd < 0)
                return -errno;

        buf = malloc(sizeof(uint32_t) + size);
        if (!buf)
                return -ENOMEM;

        buf->attr = EFI_VARIABLE_NON_VOLATILE|EFI_VARIABLE_BOOTSERVICE_ACCESS|EFI_VARIABLE_RUNTIME_ACCESS;
        memcpy(buf->buf, value, size);

        return loop_write(fd, buf, sizeof(uint32_t) + size, false);
}

int efi_get_variable_string(sd_id128_t vendor, const char *name, char **p) {
        _cleanup_free_ void *s = NULL;
        size_t ss = 0;
        int r;
        char *x;

        r = efi_get_variable(vendor, name, NULL, &s, &ss);
        if (r < 0)
                return r;

        x = utf16_to_utf8(s, ss);
        if (!x)
                return -ENOMEM;

        *p = x;
        return 0;
}

static size_t utf16_size(const uint16_t *s) {
        size_t l = 0;

        while (s[l] > 0)
                l++;

        return (l+1) * sizeof(uint16_t);
}

static void efi_guid_to_id128(const void *guid, sd_id128_t *id128) {
        struct uuid {
                uint32_t u1;
                uint16_t u2;
                uint16_t u3;
                uint8_t u4[8];
        } _packed_;
        const struct uuid *uuid = guid;

        id128->bytes[0] = (uuid->u1 >> 24) & 0xff;
        id128->bytes[1] = (uuid->u1 >> 16) & 0xff;
        id128->bytes[2] = (uuid->u1 >> 8) & 0xff;
        id128->bytes[3] = (uuid->u1) & 0xff;
        id128->bytes[4] = (uuid->u2 >> 8) & 0xff;
        id128->bytes[5] = (uuid->u2) & 0xff;
        id128->bytes[6] = (uuid->u3 >> 8) & 0xff;
        id128->bytes[7] = (uuid->u3) & 0xff;
        memcpy(&id128->bytes[8], uuid->u4, sizeof(uuid->u4));
}

int efi_get_boot_option(
                uint16_t id,
                char **title,
                sd_id128_t *part_uuid,
                char **path,
                bool *active) {

        char boot_id[9];
        _cleanup_free_ uint8_t *buf = NULL;
        size_t l;
        struct boot_option *header;
        size_t title_size;
        _cleanup_free_ char *s = NULL, *p = NULL;
        sd_id128_t p_uuid = SD_ID128_NULL;
        int r;

        xsprintf(boot_id, "Boot%04X", id);
        r = efi_get_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, (void **)&buf, &l);
        if (r < 0)
                return r;
        if (l < sizeof(struct boot_option))
                return -ENOENT;

        header = (struct boot_option *)buf;
        title_size = utf16_size(header->title);
        if (title_size > l - offsetof(struct boot_option, title))
                return -EINVAL;

        if (title) {
                s = utf16_to_utf8(header->title, title_size);
                if (!s)
                        return -ENOMEM;
        }

        if (header->path_len > 0) {
                uint8_t *dbuf;
                size_t dnext;

                dbuf = buf + offsetof(struct boot_option, title) + title_size;
                dnext = 0;
                while (dnext < header->path_len) {
                        struct device_path *dpath;

                        dpath = (struct device_path *)(dbuf + dnext);
                        if (dpath->length < 4)
                                break;

                        /* Type 0x7F – End of Hardware Device Path, Sub-Type 0xFF – End Entire Device Path */
                        if (dpath->type == END_DEVICE_PATH_TYPE && dpath->sub_type == END_ENTIRE_DEVICE_PATH_SUBTYPE)
                                break;

                        dnext += dpath->length;

                        /* Type 0x04 – Media Device Path */
                        if (dpath->type != MEDIA_DEVICE_PATH)
                                continue;

                        /* Sub-Type 1 – Hard Drive */
                        if (dpath->sub_type == MEDIA_HARDDRIVE_DP) {
                                /* 0x02 – GUID Partition Table */
                                if (dpath->drive.mbr_type != MBR_TYPE_EFI_PARTITION_TABLE_HEADER)
                                        continue;

                                /* 0x02 – GUID signature */
                                if (dpath->drive.signature_type != SIGNATURE_TYPE_GUID)
                                        continue;

                                if (part_uuid)
                                        efi_guid_to_id128(dpath->drive.signature, &p_uuid);
                                continue;
                        }

                        /* Sub-Type 4 – File Path */
                        if (dpath->sub_type == MEDIA_FILEPATH_DP && !p && path) {
                                p = utf16_to_utf8(dpath->path, dpath->length-4);
                                efi_tilt_backslashes(p);
                                continue;
                        }
                }
        }

        if (title) {
                *title = s;
                s = NULL;
        }
        if (part_uuid)
                *part_uuid = p_uuid;
        if (path) {
                *path = p;
                p = NULL;
        }
        if (active)
                *active = !!(header->attr & LOAD_OPTION_ACTIVE);

        return 0;
}

static void to_utf16(uint16_t *dest, const char *src) {
        int i;

        for (i = 0; src[i] != '\0'; i++)
                dest[i] = src[i];
        dest[i] = '\0';
}

struct guid {
        uint32_t u1;
        uint16_t u2;
        uint16_t u3;
        uint8_t u4[8];
} _packed_;

static void id128_to_efi_guid(sd_id128_t id, void *guid) {
        struct guid *uuid = guid;

        uuid->u1 = id.bytes[0] << 24 | id.bytes[1] << 16 | id.bytes[2] << 8 | id.bytes[3];
        uuid->u2 = id.bytes[4] << 8 | id.bytes[5];
        uuid->u3 = id.bytes[6] << 8 | id.bytes[7];
        memcpy(uuid->u4, id.bytes+8, sizeof(uuid->u4));
}

static uint16_t *tilt_slashes(uint16_t *s) {
        uint16_t *p;

        for (p = s; *p; p++)
                if (*p == '/')
                        *p = '\\';

        return s;
}

int efi_add_boot_option(uint16_t id, const char *title,
                        uint32_t part, uint64_t pstart, uint64_t psize,
                        sd_id128_t part_uuid, const char *path) {
        char boot_id[9];
        size_t size;
        size_t title_len;
        size_t path_len;
        struct boot_option *option;
        struct device_path *devicep;
        _cleanup_free_ char *buf = NULL;

        title_len = (strlen(title)+1) * 2;
        path_len = (strlen(path)+1) * 2;

        buf = calloc(sizeof(struct boot_option) + title_len +
                     sizeof(struct drive_path) +
                     sizeof(struct device_path) + path_len, 1);
        if (!buf)
                return -ENOMEM;

        /* header */
        option = (struct boot_option *)buf;
        option->attr = LOAD_OPTION_ACTIVE;
        option->path_len = offsetof(struct device_path, drive) + sizeof(struct drive_path) +
                           offsetof(struct device_path, path) + path_len +
                           offsetof(struct device_path, path);
        to_utf16(option->title, title);
        size = offsetof(struct boot_option, title) + title_len;

        /* partition info */
        devicep = (struct device_path *)(buf + size);
        devicep->type = MEDIA_DEVICE_PATH;
        devicep->sub_type = MEDIA_HARDDRIVE_DP;
        devicep->length = offsetof(struct device_path, drive) + sizeof(struct drive_path);
        devicep->drive.part_nr = part;
        devicep->drive.part_start = pstart;
        devicep->drive.part_size = psize;
        devicep->drive.signature_type = SIGNATURE_TYPE_GUID;
        devicep->drive.mbr_type = MBR_TYPE_EFI_PARTITION_TABLE_HEADER;
        id128_to_efi_guid(part_uuid, devicep->drive.signature);
        size += devicep->length;

        /* path to loader */
        devicep = (struct device_path *)(buf + size);
        devicep->type = MEDIA_DEVICE_PATH;
        devicep->sub_type = MEDIA_FILEPATH_DP;
        devicep->length = offsetof(struct device_path, path) + path_len;
        to_utf16(devicep->path, path);
        tilt_slashes(devicep->path);
        size += devicep->length;

        /* end of path */
        devicep = (struct device_path *)(buf + size);
        devicep->type = END_DEVICE_PATH_TYPE;
        devicep->sub_type = END_ENTIRE_DEVICE_PATH_SUBTYPE;
        devicep->length = offsetof(struct device_path, path);
        size += devicep->length;

        xsprintf(boot_id, "Boot%04X", id);
        return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, buf, size);
}

int efi_remove_boot_option(uint16_t id) {
        char boot_id[9];

        xsprintf(boot_id, "Boot%04X", id);
        return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, 0);
}

int efi_get_boot_order(uint16_t **order) {
        _cleanup_free_ void *buf = NULL;
        size_t l;
        int r;

        r = efi_get_variable(EFI_VENDOR_GLOBAL, "BootOrder", NULL, &buf, &l);
        if (r < 0)
                return r;

        if (l <= 0)
                return -ENOENT;

        if (l % sizeof(uint16_t) > 0 ||
            l / sizeof(uint16_t) > INT_MAX)
                return -EINVAL;

        *order = buf;
        buf = NULL;
        return (int) (l / sizeof(uint16_t));
}

int efi_set_boot_order(uint16_t *order, size_t n) {
        return efi_set_variable(EFI_VENDOR_GLOBAL, "BootOrder", order, n * sizeof(uint16_t));
}

static int boot_id_hex(const char s[4]) {
        int i;
        int id = 0;

        for (i = 0; i < 4; i++)
                if (s[i] >= '0' && s[i] <= '9')
                        id |= (s[i] - '0') << (3 - i) * 4;
                else if (s[i] >= 'A' && s[i] <= 'F')
                        id |= (s[i] - 'A' + 10) << (3 - i) * 4;
                else
                        return -EINVAL;

        return id;
}

static int cmp_uint16(const void *_a, const void *_b) {
        const uint16_t *a = _a, *b = _b;

        return (int)*a - (int)*b;
}

int efi_get_boot_options(uint16_t **options) {
        _cleanup_closedir_ DIR *dir = NULL;
        struct dirent *de;
        _cleanup_free_ uint16_t *list = NULL;
        size_t alloc = 0;
        int count = 0;

        assert(options);

        dir = opendir("/sys/firmware/efi/efivars/");
        if (!dir)
                return -errno;

        FOREACH_DIRENT(de, dir, return -errno) {
                int id;

                if (strncmp(de->d_name, "Boot", 4) != 0)
                        continue;

                if (strlen(de->d_name) != 45)
                        continue;

                if (strcmp(de->d_name + 8, "-8be4df61-93ca-11d2-aa0d-00e098032b8c") != 0)
                        continue;

                id = boot_id_hex(de->d_name + 4);
                if (id < 0)
                        continue;

                if (!GREEDY_REALLOC(list, alloc, count + 1))
                        return -ENOMEM;

                list[count++] = id;
        }

        qsort_safe(list, count, sizeof(uint16_t), cmp_uint16);

        *options = list;
        list = NULL;
        return count;
}

static int read_usec(sd_id128_t vendor, const char *name, usec_t *u) {
        _cleanup_free_ char *j = NULL;
        int r;
        uint64_t x = 0;

        assert(name);
        assert(u);

        r = efi_get_variable_string(EFI_VENDOR_LOADER, name, &j);
        if (r < 0)
                return r;

        r = safe_atou64(j, &x);
        if (r < 0)
                return r;

        *u = x;
        return 0;
}

int efi_loader_get_boot_usec(usec_t *firmware, usec_t *loader) {
        uint64_t x, y;
        int r;

        assert(firmware);
        assert(loader);

        r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeInitUSec", &x);
        if (r < 0)
                return r;

        r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeExecUSec", &y);
        if (r < 0)
                return r;

        if (y == 0 || y < x)
                return -EIO;

        if (y > USEC_PER_HOUR)
                return -EIO;

        *firmware = x;
        *loader = y;

        return 0;
}

int efi_loader_get_device_part_uuid(sd_id128_t *u) {
        _cleanup_free_ char *p = NULL;
        int r, parsed[16];

        r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderDevicePartUUID", &p);
        if (r < 0)
                return r;

        if (sscanf(p, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
                   &parsed[0], &parsed[1], &parsed[2], &parsed[3],
                   &parsed[4], &parsed[5], &parsed[6], &parsed[7],
                   &parsed[8], &parsed[9], &parsed[10], &parsed[11],
                   &parsed[12], &parsed[13], &parsed[14], &parsed[15]) != 16)
                return -EIO;

        if (u) {
                unsigned i;

                for (i = 0; i < ELEMENTSOF(parsed); i++)
                        u->bytes[i] = parsed[i];
        }

        return 0;
}

#endif

char *efi_tilt_backslashes(char *s) {
        char *p;

        for (p = s; *p; p++)
                if (*p == '\\')
                        *p = '/';

        return s;
}
Commit	Line	Data
2e3d0692 LP	1	/***
	2	This file is part of systemd.
	3
	4	Copyright 2013 Lennart Poettering
	5
	6	systemd is free software; you can redistribute it and/or modify it
	7	under the terms of the GNU Lesser General Public License as published by
	8	the Free Software Foundation; either version 2.1 of the License, or
	9	(at your option) any later version.
	10
	11	systemd is distributed in the hope that it will be useful, but
	12	WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	Lesser General Public License for more details.
	15
	16	You should have received a copy of the GNU Lesser General Public License
	17	along with systemd; If not, see <http://www.gnu.org/licenses/>.
	18	***/
	19
a8fbdf54 TA	20	#include <dirent.h>
a8fbdf54 TA	21	#include <errno.h>
2e3d0692	22	#include <fcntl.h>
a8fbdf54 TA	23	#include <limits.h>
	24	#include <stdio.h>
	25	#include <stdlib.h>
cf0fbc49	26	#include <string.h>
a8fbdf54	27	#include <sys/stat.h>
cf0fbc49	28	#include <unistd.h>
2e3d0692	29
a8fbdf54 TA	30	#include "sd-id128.h"
a8fbdf54 TA	31
b5efdb8a	32	#include "alloc-util.h"
a0956174	33	#include "dirent-util.h"
3ffd4af2 LP	34	#include "efivars.h"
3ffd4af2 LP	35	#include "fd-util.h"
c004493c	36	#include "io-util.h"
a8fbdf54	37	#include "macro.h"
6bedfcbb	38	#include "parse-util.h"
15a5e950	39	#include "stdio-util.h"
a8fbdf54	40	#include "time-util.h"
2e3d0692	41	#include "utf8.h"
3ffd4af2	42	#include "util.h"
5bdf2243	43	#include "virt.h"
2e3d0692	44
349cc4a5	45	#if ENABLE_EFI
b872e9a0	46
0974a682 KS	47	#define LOAD_OPTION_ACTIVE 0x00000001
	48	#define MEDIA_DEVICE_PATH 0x04
	49	#define MEDIA_HARDDRIVE_DP 0x01
	50	#define MEDIA_FILEPATH_DP 0x04
	51	#define SIGNATURE_TYPE_GUID 0x02
	52	#define MBR_TYPE_EFI_PARTITION_TABLE_HEADER 0x02
	53	#define END_DEVICE_PATH_TYPE 0x7f
	54	#define END_ENTIRE_DEVICE_PATH_SUBTYPE 0xff
5bdf2243	55	#define EFI_OS_INDICATIONS_BOOT_TO_FW_UI 0x0000000000000001
0974a682 KS	56
	57	struct boot_option {
	58	uint32_t attr;
	59	uint16_t path_len;
	60	uint16_t title[];
885fdebc	61	} _packed_;
0974a682 KS	62
	63	struct drive_path {
	64	uint32_t part_nr;
	65	uint64_t part_start;
	66	uint64_t part_size;
	67	char signature[16];
	68	uint8_t mbr_type;
	69	uint8_t signature_type;
885fdebc	70	} _packed_;
0974a682 KS	71
	72	struct device_path {
	73	uint8_t type;
	74	uint8_t sub_type;
	75	uint16_t length;
	76	union {
	77	uint16_t path[0];
	78	struct drive_path drive;
	79	};
885fdebc	80	} _packed_;
0974a682	81
9cde64ff	82	bool is_efi_boot(void) {
34e5a31e LP	83	return access("/sys/firmware/efi", F_OK) >= 0;
	84	}
	85
bc6f2e7c KS	86	static int read_flag(const char *varname) {
bc6f2e7c KS	87	int r;
b47d419c	88	_cleanup_free_ void *v = NULL;
bc6f2e7c KS	89	size_t s;
	90	uint8_t b;
	91
	92	r = efi_get_variable(EFI_VENDOR_GLOBAL, varname, NULL, &v, &s);
	93	if (r < 0)
	94	return r;
	95
b47d419c ZJS	96	if (s != 1)
b47d419c ZJS	97	return -EINVAL;
bc6f2e7c KS	98
	99	b = (uint8_t )v;
	100	r = b > 0;
bc6f2e7c KS	101	return r;
	102	}
	103
9df49b33 TG	104	bool is_efi_secure_boot(void) {
9df49b33 TG	105	return read_flag("SecureBoot") > 0;
bc6f2e7c KS	106	}
bc6f2e7c KS	107
9df49b33 TG	108	bool is_efi_secure_boot_setup_mode(void) {
9df49b33 TG	109	return read_flag("SetupMode") > 0;
bc6f2e7c KS	110	}
bc6f2e7c KS	111
5bdf2243 JJ	112	int efi_reboot_to_firmware_supported(void) {
	113	int r;
	114	size_t s;
	115	uint64_t b;
	116	_cleanup_free_ void *v = NULL;
	117
75f86906	118	if (!is_efi_boot() \|\| detect_container() > 0)
5bdf2243 JJ	119	return -EOPNOTSUPP;
	120
	121	r = efi_get_variable(EFI_VENDOR_GLOBAL, "OsIndicationsSupported", NULL, &v, &s);
	122	if (r < 0)
	123	return r;
	124	else if (s != sizeof(uint64_t))
	125	return -EINVAL;
	126
	127	b = (uint64_t )v;
	128	b &= EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
	129	return b > 0 ? 0 : -EOPNOTSUPP;
	130	}
	131
	132	static int get_os_indications(uint64_t *os_indication) {
	133	int r;
	134	size_t s;
	135	_cleanup_free_ void *v = NULL;
	136
	137	r = efi_reboot_to_firmware_supported();
	138	if (r < 0)
	139	return r;
	140
	141	r = efi_get_variable(EFI_VENDOR_GLOBAL, "OsIndications", NULL, &v, &s);
6b62bbbc LP	142	if (r == -ENOENT) {
	143	/* Some firmware implementations that do support
	144	* OsIndications and report that with
	145	* OsIndicationsSupported will remove the
	146	* OsIndications variable when it is unset. Let's
	147	* pretend it's 0 then, to hide this implementation
	148	* detail. Note that this call will return -ENOENT
	149	* then only if the support for OsIndications is
	150	* missing entirely, as determined by
	151	* efi_reboot_to_firmware_supported() above. */
	152	*os_indication = 0;
	153	return 0;
	154	} else if (r < 0)
5bdf2243 JJ	155	return r;
	156	else if (s != sizeof(uint64_t))
	157	return -EINVAL;
	158
	159	os_indication = (uint64_t *)v;
	160	return 0;
	161	}
	162
	163	int efi_get_reboot_to_firmware(void) {
	164	int r;
	165	uint64_t b;
	166
	167	r = get_os_indications(&b);
	168	if (r < 0)
	169	return r;
	170
	171	return !!(b & EFI_OS_INDICATIONS_BOOT_TO_FW_UI);
	172	}
	173
	174	int efi_set_reboot_to_firmware(bool value) {
	175	int r;
	176	uint64_t b, b_new;
	177
	178	r = get_os_indications(&b);
	179	if (r < 0)
	180	return r;
	181
	182	if (value)
	183	b_new = b \| EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
	184	else
	185	b_new = b & ~EFI_OS_INDICATIONS_BOOT_TO_FW_UI;
	186
	187	/* Avoid writing to efi vars store if we can due to firmware bugs. */
	188	if (b != b_new)
	189	return efi_set_variable(EFI_VENDOR_GLOBAL, "OsIndications", &b_new, sizeof(uint64_t));
	190
	191	return 0;
	192	}
	193
9cde64ff LP	194	int efi_get_variable(
	195	sd_id128_t vendor,
	196	const char *name,
	197	uint32_t *attribute,
	198	void **value,
	199	size_t *size) {
	200
2e3d0692 LP	201	_cleanup_close_ int fd = -1;
	202	_cleanup_free_ char *p = NULL;
	203	uint32_t a;
	204	ssize_t n;
	205	struct stat st;
ad7bcf52	206	_cleanup_free_ void *buf = NULL;
2e3d0692 LP	207
	208	assert(name);
	209	assert(value);
	210	assert(size);
	211
	212	if (asprintf(&p,
	213	"/sys/firmware/efi/efivars/%s-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
	214	name, SD_ID128_FORMAT_VAL(vendor)) < 0)
	215	return -ENOMEM;
	216
	217	fd = open(p, O_RDONLY\|O_NOCTTY\|O_CLOEXEC);
	218	if (fd < 0)
	219	return -errno;
	220
	221	if (fstat(fd, &st) < 0)
	222	return -errno;
	223	if (st.st_size < 4)
	224	return -EIO;
	225	if (st.st_size > 410241024 + 4)
	226	return -E2BIG;
	227
	228	n = read(fd, &a, sizeof(a));
	229	if (n < 0)
9cde64ff	230	return -errno;
2e3d0692 LP	231	if (n != sizeof(a))
	232	return -EIO;
	233
0797f232 ZJS	234	buf = malloc(st.st_size - 4 + 2);
0797f232 ZJS	235	if (!buf)
2e3d0692 LP	236	return -ENOMEM;
2e3d0692 LP	237
0797f232 ZJS	238	n = read(fd, buf, (size_t) st.st_size - 4);
0797f232 ZJS	239	if (n < 0)
742af54a	240	return -errno;
0797f232	241	if (n != (ssize_t) st.st_size - 4)
2e3d0692	242	return -EIO;
2e3d0692 LP	243
2e3d0692 LP	244	/* Always NUL terminate (2 bytes, to protect UTF-16) */
0797f232 ZJS	245	((char*) buf)[st.st_size - 4] = 0;
0797f232 ZJS	246	((char*) buf)[st.st_size - 4 + 1] = 0;
2e3d0692	247
0797f232 ZJS	248	*value = buf;
0797f232 ZJS	249	buf = NULL;
ff47c895	250	*size = (size_t) st.st_size - 4;
2e3d0692 LP	251
	252	if (attribute)
	253	*attribute = a;
	254
	255	return 0;
	256	}
	257
0974a682 KS	258	int efi_set_variable(
	259	sd_id128_t vendor,
	260	const char *name,
	261	const void *value,
	262	size_t size) {
	263
	264	struct var {
	265	uint32_t attr;
	266	char buf[];
b7749eb5 ZJS	267	} _packed_ * _cleanup_free_ buf = NULL;
	268	_cleanup_free_ char *p = NULL;
	269	_cleanup_close_ int fd = -1;
0974a682 KS	270
0974a682 KS	271	assert(name);
e1e26566	272	assert(value \|\| size == 0);
0974a682 KS	273
	274	if (asprintf(&p,
	275	"/sys/firmware/efi/efivars/%s-%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
	276	name, SD_ID128_FORMAT_VAL(vendor)) < 0)
	277	return -ENOMEM;
	278
	279	if (size == 0) {
b7749eb5 ZJS	280	if (unlink(p) < 0)
	281	return -errno;
	282	return 0;
0974a682 KS	283	}
	284
	285	fd = open(p, O_WRONLY\|O_CREAT\|O_NOCTTY\|O_CLOEXEC, 0644);
b7749eb5 ZJS	286	if (fd < 0)
b7749eb5 ZJS	287	return -errno;
0974a682 KS	288
0974a682 KS	289	buf = malloc(sizeof(uint32_t) + size);
b7749eb5 ZJS	290	if (!buf)
b7749eb5 ZJS	291	return -ENOMEM;
0974a682 KS	292
	293	buf->attr = EFI_VARIABLE_NON_VOLATILE\|EFI_VARIABLE_BOOTSERVICE_ACCESS\|EFI_VARIABLE_RUNTIME_ACCESS;
	294	memcpy(buf->buf, value, size);
	295
b7749eb5	296	return loop_write(fd, buf, sizeof(uint32_t) + size, false);
0974a682 KS	297	}
0974a682 KS	298
9cde64ff	299	int efi_get_variable_string(sd_id128_t vendor, const char name, char *p) {
7b4d7cc0	300	_cleanup_free_ void *s = NULL;
39883f62	301	size_t ss = 0;
9cde64ff LP	302	int r;
9cde64ff LP	303	char *x;
7b4d7cc0	304
9cde64ff LP	305	r = efi_get_variable(vendor, name, NULL, &s, &ss);
	306	if (r < 0)
	307	return r;
	308
	309	x = utf16_to_utf8(s, ss);
	310	if (!x)
	311	return -ENOMEM;
	312
	313	*p = x;
	314	return 0;
7b4d7cc0 KS	315	}
	316
	317	static size_t utf16_size(const uint16_t *s) {
	318	size_t l = 0;
	319
	320	while (s[l] > 0)
	321	l++;
9cde64ff	322
7b4d7cc0 KS	323	return (l+1) * sizeof(uint16_t);
	324	}
	325
	326	static void efi_guid_to_id128(const void guid, sd_id128_t id128) {
	327	struct uuid {
	328	uint32_t u1;
	329	uint16_t u2;
	330	uint16_t u3;
	331	uint8_t u4[8];
	332	} _packed_;
	333	const struct uuid *uuid = guid;
	334
	335	id128->bytes[0] = (uuid->u1 >> 24) & 0xff;
	336	id128->bytes[1] = (uuid->u1 >> 16) & 0xff;
	337	id128->bytes[2] = (uuid->u1 >> 8) & 0xff;
	338	id128->bytes[3] = (uuid->u1) & 0xff;
	339	id128->bytes[4] = (uuid->u2 >> 8) & 0xff;
	340	id128->bytes[5] = (uuid->u2) & 0xff;
	341	id128->bytes[6] = (uuid->u3 >> 8) & 0xff;
	342	id128->bytes[7] = (uuid->u3) & 0xff;
	343	memcpy(&id128->bytes[8], uuid->u4, sizeof(uuid->u4));
	344	}
	345
9cde64ff LP	346	int efi_get_boot_option(
	347	uint16_t id,
	348	char **title,
	349	sd_id128_t *part_uuid,
0974a682 KS	350	char **path,
0974a682 KS	351	bool *active) {
7b4d7cc0	352
9cde64ff LP	353	char boot_id[9];
9cde64ff LP	354	_cleanup_free_ uint8_t *buf = NULL;
7b4d7cc0 KS	355	size_t l;
	356	struct boot_option *header;
	357	size_t title_size;
b7749eb5	358	_cleanup_free_ char s = NULL, p = NULL;
7b4d7cc0	359	sd_id128_t p_uuid = SD_ID128_NULL;
a8436474	360	int r;
7b4d7cc0	361
b7749eb5	362	xsprintf(boot_id, "Boot%04X", id);
a8436474 ZJS	363	r = efi_get_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, (void **)&buf, &l);
	364	if (r < 0)
	365	return r;
7b4d7cc0 KS	366	if (l < sizeof(struct boot_option))
	367	return -ENOENT;
	368
	369	header = (struct boot_option *)buf;
	370	title_size = utf16_size(header->title);
	371	if (title_size > l - offsetof(struct boot_option, title))
	372	return -EINVAL;
	373
5483a186 ZJS	374	if (title) {
5483a186 ZJS	375	s = utf16_to_utf8(header->title, title_size);
b7749eb5 ZJS	376	if (!s)
b7749eb5 ZJS	377	return -ENOMEM;
7b4d7cc0 KS	378	}
	379
	380	if (header->path_len > 0) {
9cde64ff	381	uint8_t *dbuf;
7b4d7cc0 KS	382	size_t dnext;
	383
	384	dbuf = buf + offsetof(struct boot_option, title) + title_size;
	385	dnext = 0;
	386	while (dnext < header->path_len) {
	387	struct device_path *dpath;
	388
	389	dpath = (struct device_path *)(dbuf + dnext);
	390	if (dpath->length < 4)
	391	break;
	392
	393	/* Type 0x7F – End of Hardware Device Path, Sub-Type 0xFF – End Entire Device Path */
0974a682	394	if (dpath->type == END_DEVICE_PATH_TYPE && dpath->sub_type == END_ENTIRE_DEVICE_PATH_SUBTYPE)
7b4d7cc0 KS	395	break;
	396
	397	dnext += dpath->length;
	398
	399	/* Type 0x04 – Media Device Path */
0974a682	400	if (dpath->type != MEDIA_DEVICE_PATH)
7b4d7cc0 KS	401	continue;
	402
	403	/* Sub-Type 1 – Hard Drive */
0974a682	404	if (dpath->sub_type == MEDIA_HARDDRIVE_DP) {
7b4d7cc0	405	/* 0x02 – GUID Partition Table */
0974a682	406	if (dpath->drive.mbr_type != MBR_TYPE_EFI_PARTITION_TABLE_HEADER)
7b4d7cc0 KS	407	continue;
	408
	409	/* 0x02 – GUID signature */
0974a682	410	if (dpath->drive.signature_type != SIGNATURE_TYPE_GUID)
7b4d7cc0 KS	411	continue;
7b4d7cc0 KS	412
5483a186 ZJS	413	if (part_uuid)
5483a186 ZJS	414	efi_guid_to_id128(dpath->drive.signature, &p_uuid);
7b4d7cc0 KS	415	continue;
	416	}
	417
	418	/* Sub-Type 4 – File Path */
0974a682	419	if (dpath->sub_type == MEDIA_FILEPATH_DP && !p && path) {
7b4d7cc0	420	p = utf16_to_utf8(dpath->path, dpath->length-4);
0974a682	421	efi_tilt_backslashes(p);
7b4d7cc0 KS	422	continue;
	423	}
	424	}
	425	}
	426
b7749eb5	427	if (title) {
9cde64ff	428	*title = s;
b7749eb5 ZJS	429	s = NULL;
b7749eb5 ZJS	430	}
7b4d7cc0 KS	431	if (part_uuid)
7b4d7cc0 KS	432	*part_uuid = p_uuid;
b7749eb5	433	if (path) {
7b4d7cc0	434	*path = p;
b7749eb5 ZJS	435	p = NULL;
b7749eb5 ZJS	436	}
0974a682	437	if (active)
0aa3b783	438	*active = !!(header->attr & LOAD_OPTION_ACTIVE);
9cde64ff	439
7b4d7cc0	440	return 0;
7b4d7cc0 KS	441	}
7b4d7cc0 KS	442
0974a682 KS	443	static void to_utf16(uint16_t dest, const char src) {
	444	int i;
	445
	446	for (i = 0; src[i] != '\0'; i++)
	447	dest[i] = src[i];
	448	dest[i] = '\0';
	449	}
	450
	451	struct guid {
	452	uint32_t u1;
	453	uint16_t u2;
	454	uint16_t u3;
	455	uint8_t u4[8];
885fdebc	456	} _packed_;
0974a682 KS	457
	458	static void id128_to_efi_guid(sd_id128_t id, void *guid) {
	459	struct guid *uuid = guid;
	460
	461	uuid->u1 = id.bytes[0] << 24 \| id.bytes[1] << 16 \| id.bytes[2] << 8 \| id.bytes[3];
	462	uuid->u2 = id.bytes[4] << 8 \| id.bytes[5];
	463	uuid->u3 = id.bytes[6] << 8 \| id.bytes[7];
	464	memcpy(uuid->u4, id.bytes+8, sizeof(uuid->u4));
	465	}
	466
	467	static uint16_t tilt_slashes(uint16_t s) {
	468	uint16_t *p;
	469
	470	for (p = s; *p; p++)
	471	if (*p == '/')
	472	*p = '\\';
	473
	474	return s;
	475	}
	476
0974a682 KS	477	int efi_add_boot_option(uint16_t id, const char *title,
	478	uint32_t part, uint64_t pstart, uint64_t psize,
	479	sd_id128_t part_uuid, const char *path) {
	480	char boot_id[9];
0974a682 KS	481	size_t size;
	482	size_t title_len;
	483	size_t path_len;
	484	struct boot_option *option;
	485	struct device_path *devicep;
b7749eb5	486	_cleanup_free_ char *buf = NULL;
0974a682 KS	487
	488	title_len = (strlen(title)+1) * 2;
	489	path_len = (strlen(path)+1) * 2;
	490
	491	buf = calloc(sizeof(struct boot_option) + title_len +
	492	sizeof(struct drive_path) +
	493	sizeof(struct device_path) + path_len, 1);
b7749eb5 ZJS	494	if (!buf)
b7749eb5 ZJS	495	return -ENOMEM;
0974a682 KS	496
	497	/* header */
	498	option = (struct boot_option *)buf;
	499	option->attr = LOAD_OPTION_ACTIVE;
	500	option->path_len = offsetof(struct device_path, drive) + sizeof(struct drive_path) +
	501	offsetof(struct device_path, path) + path_len +
	502	offsetof(struct device_path, path);
	503	to_utf16(option->title, title);
	504	size = offsetof(struct boot_option, title) + title_len;
	505
	506	/* partition info */
	507	devicep = (struct device_path *)(buf + size);
	508	devicep->type = MEDIA_DEVICE_PATH;
	509	devicep->sub_type = MEDIA_HARDDRIVE_DP;
	510	devicep->length = offsetof(struct device_path, drive) + sizeof(struct drive_path);
	511	devicep->drive.part_nr = part;
	512	devicep->drive.part_start = pstart;
920b52e4	513	devicep->drive.part_size = psize;
0974a682 KS	514	devicep->drive.signature_type = SIGNATURE_TYPE_GUID;
	515	devicep->drive.mbr_type = MBR_TYPE_EFI_PARTITION_TABLE_HEADER;
	516	id128_to_efi_guid(part_uuid, devicep->drive.signature);
	517	size += devicep->length;
	518
	519	/* path to loader */
	520	devicep = (struct device_path *)(buf + size);
	521	devicep->type = MEDIA_DEVICE_PATH;
	522	devicep->sub_type = MEDIA_FILEPATH_DP;
	523	devicep->length = offsetof(struct device_path, path) + path_len;
	524	to_utf16(devicep->path, path);
	525	tilt_slashes(devicep->path);
	526	size += devicep->length;
	527
	528	/* end of path */
	529	devicep = (struct device_path *)(buf + size);
	530	devicep->type = END_DEVICE_PATH_TYPE;
	531	devicep->sub_type = END_ENTIRE_DEVICE_PATH_SUBTYPE;
	532	devicep->length = offsetof(struct device_path, path);
	533	size += devicep->length;
	534
b7749eb5 ZJS	535	xsprintf(boot_id, "Boot%04X", id);
b7749eb5 ZJS	536	return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, buf, size);
0974a682 KS	537	}
	538
	539	int efi_remove_boot_option(uint16_t id) {
	540	char boot_id[9];
	541
b7749eb5	542	xsprintf(boot_id, "Boot%04X", id);
0974a682 KS	543	return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, 0);
	544	}
	545
9cde64ff	546	int efi_get_boot_order(uint16_t **order) {
0797f232	547	_cleanup_free_ void *buf = NULL;
7b4d7cc0	548	size_t l;
9cde64ff	549	int r;
7b4d7cc0	550
9cde64ff LP	551	r = efi_get_variable(EFI_VENDOR_GLOBAL, "BootOrder", NULL, &buf, &l);
	552	if (r < 0)
	553	return r;
7b4d7cc0	554
0797f232	555	if (l <= 0)
7b4d7cc0	556	return -ENOENT;
7b4d7cc0	557
0797f232 ZJS	558	if (l % sizeof(uint16_t) > 0 \|\|
0797f232 ZJS	559	l / sizeof(uint16_t) > INT_MAX)
7b4d7cc0	560	return -EINVAL;
7b4d7cc0 KS	561
7b4d7cc0 KS	562	*order = buf;
0797f232	563	buf = NULL;
9cde64ff LP	564	return (int) (l / sizeof(uint16_t));
	565	}
	566
0974a682 KS	567	int efi_set_boot_order(uint16_t *order, size_t n) {
	568	return efi_set_variable(EFI_VENDOR_GLOBAL, "BootOrder", order, n * sizeof(uint16_t));
	569	}
	570
4d34c495 KS	571	static int boot_id_hex(const char s[4]) {
	572	int i;
	573	int id = 0;
	574
	575	for (i = 0; i < 4; i++)
	576	if (s[i] >= '0' && s[i] <= '9')
	577	id \|= (s[i] - '0') << (3 - i) * 4;
	578	else if (s[i] >= 'A' && s[i] <= 'F')
	579	id \|= (s[i] - 'A' + 10) << (3 - i) * 4;
	580	else
7e8185ef	581	return -EINVAL;
4d34c495 KS	582
	583	return id;
	584	}
	585
9db11a99 LP	586	static int cmp_uint16(const void _a, const void _b) {
	587	const uint16_t a = _a, b = _b;
	588
02a6fc3e	589	return (int)a - (int)b;
9db11a99 LP	590	}
9db11a99 LP	591
9cde64ff LP	592	int efi_get_boot_options(uint16_t **options) {
	593	_cleanup_closedir_ DIR *dir = NULL;
	594	struct dirent *de;
b7749eb5	595	_cleanup_free_ uint16_t *list = NULL;
7432b24b	596	size_t alloc = 0;
b7749eb5	597	int count = 0;
9cde64ff LP	598
	599	assert(options);
	600
	601	dir = opendir("/sys/firmware/efi/efivars/");
	602	if (!dir)
	603	return -errno;
	604
b7749eb5	605	FOREACH_DIRENT(de, dir, return -errno) {
4d34c495	606	int id;
9cde64ff LP	607
	608	if (strncmp(de->d_name, "Boot", 4) != 0)
	609	continue;
	610
4d34c495	611	if (strlen(de->d_name) != 45)
9cde64ff LP	612	continue;
	613
	614	if (strcmp(de->d_name + 8, "-8be4df61-93ca-11d2-aa0d-00e098032b8c") != 0)
	615	continue;
	616
4d34c495 KS	617	id = boot_id_hex(de->d_name + 4);
4d34c495 KS	618	if (id < 0)
9cde64ff LP	619	continue;
9cde64ff LP	620
7432b24b	621	if (!GREEDY_REALLOC(list, alloc, count + 1))
b7749eb5	622	return -ENOMEM;
9cde64ff	623
7432b24b	624	list[count++] = id;
9cde64ff LP	625	}
9cde64ff LP	626
7ff7394d	627	qsort_safe(list, count, sizeof(uint16_t), cmp_uint16);
9db11a99	628
9cde64ff	629	*options = list;
b7749eb5	630	list = NULL;
9cde64ff	631	return count;
7b4d7cc0 KS	632	}
7b4d7cc0 KS	633
5dbe9f53	634	static int read_usec(sd_id128_t vendor, const char name, usec_t u) {
2e3d0692	635	_cleanup_free_ char *j = NULL;
2e3d0692	636	int r;
39883f62	637	uint64_t x = 0;
2e3d0692 LP	638
	639	assert(name);
	640	assert(u);
	641
61cc634b	642	r = efi_get_variable_string(EFI_VENDOR_LOADER, name, &j);
2e3d0692 LP	643	if (r < 0)
	644	return r;
	645
2e3d0692 LP	646	r = safe_atou64(j, &x);
	647	if (r < 0)
	648	return r;
	649
5dbe9f53	650	*u = x;
2e3d0692 LP	651	return 0;
	652	}
	653
c51d84dc	654	int efi_loader_get_boot_usec(usec_t firmware, usec_t loader) {
2e3d0692 LP	655	uint64_t x, y;
2e3d0692 LP	656	int r;
2e3d0692 LP	657
	658	assert(firmware);
	659	assert(loader);
	660
e9cea16d	661	r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeInitUSec", &x);
2e3d0692 LP	662	if (r < 0)
	663	return r;
	664
e9cea16d	665	r = read_usec(EFI_VENDOR_LOADER, "LoaderTimeExecUSec", &y);
2e3d0692 LP	666	if (r < 0)
	667	return r;
	668
	669	if (y == 0 \|\| y < x)
	670	return -EIO;
	671
	672	if (y > USEC_PER_HOUR)
	673	return -EIO;
	674
	675	*firmware = x;
	676	*loader = y;
	677
	678	return 0;
	679	}
	680
c51d84dc	681	int efi_loader_get_device_part_uuid(sd_id128_t *u) {
f4ce2b3e	682	_cleanup_free_ char *p = NULL;
f4ce2b3e	683	int r, parsed[16];
f4ce2b3e	684
61cc634b	685	r = efi_get_variable_string(EFI_VENDOR_LOADER, "LoaderDevicePartUUID", &p);
f4ce2b3e LP	686	if (r < 0)
	687	return r;
	688
f4ce2b3e LP	689	if (sscanf(p, "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
	690	&parsed[0], &parsed[1], &parsed[2], &parsed[3],
	691	&parsed[4], &parsed[5], &parsed[6], &parsed[7],
	692	&parsed[8], &parsed[9], &parsed[10], &parsed[11],
	693	&parsed[12], &parsed[13], &parsed[14], &parsed[15]) != 16)
	694	return -EIO;
	695
73b80ec2 LP	696	if (u) {
	697	unsigned i;
	698
	699	for (i = 0; i < ELEMENTSOF(parsed); i++)
	700	u->bytes[i] = parsed[i];
	701	}
f4ce2b3e LP	702
	703	return 0;
	704	}
b872e9a0 LP	705
b872e9a0 LP	706	#endif
b28ce7c6 TG	707
	708	char efi_tilt_backslashes(char s) {
	709	char *p;
	710
	711	for (p = s; *p; p++)
	712	if (*p == '\\')
	713	*p = '/';
	714
	715	return s;
	716	}