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Diffstat (limited to 'src/shared/efivars.c')
-rw-r--r--src/shared/efivars.c406
1 files changed, 315 insertions, 91 deletions
diff --git a/src/shared/efivars.c b/src/shared/efivars.c
index a319574527..d34d977b9a 100644
--- a/src/shared/efivars.c
+++ b/src/shared/efivars.c
@@ -22,15 +22,49 @@
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
-#include <ctype.h>
-#include "acpi-fpdt.h"
#include "util.h"
#include "utf8.h"
+#include "virt.h"
#include "efivars.h"
#ifdef 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;
}
@@ -53,12 +87,82 @@ static int read_flag(const char *varname) {
return r;
}
-int is_efi_secure_boot(void) {
- return read_flag("SecureBoot");
+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(NULL) > 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 < 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 is_efi_secure_boot_setup_mode(void) {
- return read_flag("SetupMode");
+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(
@@ -73,7 +177,7 @@ int efi_get_variable(
uint32_t a;
ssize_t n;
struct stat st;
- void *r;
+ _cleanup_free_ void *buf = NULL;
assert(name);
assert(value);
@@ -101,25 +205,22 @@ int efi_get_variable(
if (n != sizeof(a))
return -EIO;
- r = malloc(st.st_size - 4 + 2);
- if (!r)
+ buf = malloc(st.st_size - 4 + 2);
+ if (!buf)
return -ENOMEM;
- n = read(fd, r, (size_t) st.st_size - 4);
- if (n < 0) {
- free(r);
+ n = read(fd, buf, (size_t) st.st_size - 4);
+ if (n < 0)
return -errno;
- }
- if (n != (ssize_t) st.st_size - 4) {
- free(r);
+ if (n != (ssize_t) st.st_size - 4)
return -EIO;
- }
/* Always NUL terminate (2 bytes, to protect UTF-16) */
- ((char*) r)[st.st_size - 4] = 0;
- ((char*) r)[st.st_size - 4 + 1] = 0;
+ ((char*) buf)[st.st_size - 4] = 0;
+ ((char*) buf)[st.st_size - 4 + 1] = 0;
- *value = r;
+ *value = buf;
+ buf = NULL;
*size = (size_t) st.st_size - 4;
if (attribute)
@@ -128,6 +229,46 @@ int efi_get_variable(
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);
+
+ 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;
@@ -179,47 +320,22 @@ int efi_get_boot_option(
uint16_t id,
char **title,
sd_id128_t *part_uuid,
- char **path) {
-
- 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_;
+ 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;
- char *s = NULL;
- char *p = NULL;
+ _cleanup_free_ char *s = NULL, *p = NULL;
sd_id128_t p_uuid = SD_ID128_NULL;
- int err;
+ int r;
- snprintf(boot_id, sizeof(boot_id), "Boot%04X", id);
- err = efi_get_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, (void **)&buf, &l);
- if (err < 0)
- return err;
+ 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;
@@ -230,10 +346,8 @@ int efi_get_boot_option(
if (title) {
s = utf16_to_utf8(header->title, title_size);
- if (!s) {
- err = -ENOMEM;
- goto err;
- }
+ if (!s)
+ return -ENOMEM;
}
if (header->path_len > 0) {
@@ -250,23 +364,23 @@ int efi_get_boot_option(
break;
/* Type 0x7F – End of Hardware Device Path, Sub-Type 0xFF – End Entire Device Path */
- if (dpath->type == 0x7f && dpath->sub_type == 0xff)
+ 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 != 0x04)
+ if (dpath->type != MEDIA_DEVICE_PATH)
continue;
/* Sub-Type 1 – Hard Drive */
- if (dpath->sub_type == 0x01) {
+ if (dpath->sub_type == MEDIA_HARDDRIVE_DP) {
/* 0x02 – GUID Partition Table */
- if (dpath->drive.mbr_type != 0x02)
+ if (dpath->drive.mbr_type != MBR_TYPE_EFI_PARTITION_TABLE_HEADER)
continue;
/* 0x02 – GUID signature */
- if (dpath->drive.signature_type != 0x02)
+ if (dpath->drive.signature_type != SIGNATURE_TYPE_GUID)
continue;
if (part_uuid)
@@ -275,29 +389,135 @@ int efi_get_boot_option(
}
/* Sub-Type 4 – File Path */
- if (dpath->sub_type == 0x04 && !p && 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)
+ if (title) {
*title = s;
+ s = NULL;
+ }
if (part_uuid)
*part_uuid = p_uuid;
- if (path)
+ if (path) {
*path = p;
+ p = NULL;
+ }
+ if (active)
+ *active = !!(header->attr & LOAD_OPTION_ACTIVE);
return 0;
-err:
- free(s);
- free(p);
- return err;
+}
+
+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) {
- void *buf;
+ _cleanup_free_ void *buf = NULL;
size_t l;
int r;
@@ -305,21 +525,22 @@ int efi_get_boot_order(uint16_t **order) {
if (r < 0)
return r;
- if (l <= 0) {
- free(buf);
+ if (l <= 0)
return -ENOENT;
- }
- if ((l % sizeof(uint16_t) > 0) ||
- (l / sizeof(uint16_t) > INT_MAX)) {
- free(buf);
+ 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;
@@ -344,8 +565,9 @@ static int cmp_uint16(const void *_a, const void *_b) {
int efi_get_boot_options(uint16_t **options) {
_cleanup_closedir_ DIR *dir = NULL;
struct dirent *de;
- uint16_t *list = NULL;
- int count = 0, r;
+ _cleanup_free_ uint16_t *list = NULL;
+ size_t alloc = 0;
+ int count = 0;
assert(options);
@@ -353,9 +575,8 @@ int efi_get_boot_options(uint16_t **options) {
if (!dir)
return -errno;
- FOREACH_DIRENT(de, dir, r = -errno; goto fail) {
+ FOREACH_DIRENT(de, dir, return -errno) {
int id;
- uint16_t *t;
if (strncmp(de->d_name, "Boot", 4) != 0)
continue;
@@ -370,24 +591,17 @@ int efi_get_boot_options(uint16_t **options) {
if (id < 0)
continue;
- t = realloc(list, (count + 1) * sizeof(uint16_t));
- if (!t) {
- r = -ENOMEM;
- goto fail;
- }
+ if (!GREEDY_REALLOC(list, alloc, count + 1))
+ return -ENOMEM;
- list = t;
- list[count ++] = id;
+ list[count++] = id;
}
qsort_safe(list, count, sizeof(uint16_t), cmp_uint16);
*options = list;
+ list = NULL;
return count;
-
-fail:
- free(list);
- return r;
}
static int read_usec(sd_id128_t vendor, const char *name, usec_t *u) {
@@ -463,3 +677,13 @@ int efi_loader_get_device_part_uuid(sd_id128_t *u) {
}
#endif
+
+char *efi_tilt_backslashes(char *s) {
+ char *p;
+
+ for (p = s; *p; p++)
+ if (*p == '\\')
+ *p = '/';
+
+ return s;
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2025-01-20 08:51:08 +0000