+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];
+} __attribute__((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;
+}
+
+char *efi_tilt_backslashes(char *s) {
+ char *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];
+ char *buf;
+ size_t size;
+ size_t title_len;
+ size_t path_len;
+ struct boot_option *option;
+ struct device_path *devicep;
+ int err;
+
+ 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) {
+ err = -ENOMEM;
+ goto finish;
+ }
+
+ /* 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;
+
+ snprintf(boot_id, sizeof(boot_id), "Boot%04X", id);
+ err = efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, buf, size);
+
+finish:
+ free(buf);
+ return err;
+}
+
+int efi_remove_boot_option(uint16_t id) {
+ char boot_id[9];
+
+ snprintf(boot_id, sizeof(boot_id), "Boot%04X", id);
+ return efi_set_variable(EFI_VENDOR_GLOBAL, boot_id, NULL, 0);
+}
+