[RFC 06/14] efi_loader: capsule: add capsule_on_disk support

AKASHI Takahiro takahiro.akashi at linaro.org
Tue Mar 17 03:12:39 CET 2020


Capsule data can be loaded into the system either via UpdateCapsule
runtime service or files on a file system (of boot device).
The latter case is called "capsules on disk", and actual updates will
take place at the next boot time.

In this commit, we will support capsule on disk mechanism.

Please note that U-Boot itself has no notion of "boot device" and
all the capsule files to be executed will be identified only if they
are located in a specific directory on a device that is determined
by "BootXXXX" variables.

Signed-off-by: AKASHI Takahiro <takahiro.akashi at linaro.org>
---
 include/efi_loader.h          |  18 ++
 lib/efi_loader/Kconfig        |   7 +
 lib/efi_loader/efi_boottime.c |   3 +
 lib/efi_loader/efi_capsule.c  | 548 ++++++++++++++++++++++++++++++++++
 lib/efi_loader/efi_setup.c    |   6 +
 5 files changed, 582 insertions(+)

diff --git a/include/efi_loader.h b/include/efi_loader.h
index c3cb7735bf50..c701672e18db 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -178,6 +178,8 @@ extern const efi_guid_t efi_guid_hii_config_routing_protocol;
 extern const efi_guid_t efi_guid_hii_config_access_protocol;
 extern const efi_guid_t efi_guid_hii_database_protocol;
 extern const efi_guid_t efi_guid_hii_string_protocol;
+/* GUID of capsule update result */
+extern const efi_guid_t efi_guid_capsule_report;
 
 /* GUID of RNG protocol */
 extern const efi_guid_t efi_guid_rng_protocol;
@@ -690,6 +692,22 @@ efi_status_t EFIAPI efi_query_capsule_caps(
 		u64 *maximum_capsule_size,
 		u32 *reset_type);
 
+#ifdef CONFIG_EFI_CAPSULE_ON_DISK
+#define EFI_CAPSULE_DIR L"\\EFI\\UpdateCapsule\\"
+
+/* Hook at initialization */
+efi_status_t efi_launch_capsules(void);
+/* Notify ExitBootServices() is called */
+void efi_capsule_boot_exit_notify(void);
+#else
+static inline efi_status_t efi_launch_capsules(void)
+{
+	return EFI_SUCCESS;
+}
+
+static inline efi_capsule_boot_exit_notify(void) {}
+#endif /* CONFIG_EFI_CAPSULE_ON_DISK */
+
 #else /* CONFIG_IS_ENABLED(EFI_LOADER) */
 
 /* Without CONFIG_EFI_LOADER we don't have a runtime section, stub it out */
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig
index 2ef6cb124f3a..95e10f7d981b 100644
--- a/lib/efi_loader/Kconfig
+++ b/lib/efi_loader/Kconfig
@@ -97,6 +97,13 @@ config EFI_CAPSULE_UPDATE
 	  Select this option if you want to use capsule update feature,
 	  including firmware updates and variable updates.
 
+config EFI_CAPSULE_ON_DISK
+	bool "Enable capsule-on-disk support"
+	depends on EFI_CAPSULE_UPDATE
+	default n
+	help
+	  Select this option if you want to use capsule-on-disk feature.
+
 config EFI_LOADER_BOUNCE_BUFFER
 	bool "EFI Applications use bounce buffers for DMA operations"
 	depends on ARM64
diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c
index 9860d5047502..c2a789b4f910 100644
--- a/lib/efi_loader/efi_boottime.c
+++ b/lib/efi_loader/efi_boottime.c
@@ -1981,6 +1981,9 @@ static efi_status_t EFIAPI efi_exit_boot_services(efi_handle_t image_handle,
 	/* Notify variable services */
 	efi_variables_boot_exit_notify();
 
+	/* Notify capsule services */
+	efi_capsule_boot_exit_notify();
+
 	/* Remove all events except EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE */
 	list_for_each_entry_safe(evt, next_event, &efi_events, link) {
 		if (evt->type != EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE)
diff --git a/lib/efi_loader/efi_capsule.c b/lib/efi_loader/efi_capsule.c
index d3f931910d10..f3e2a555a6b9 100644
--- a/lib/efi_loader/efi_capsule.c
+++ b/lib/efi_loader/efi_capsule.c
@@ -10,8 +10,14 @@
 #include <efi_loader.h>
 #include <fs.h>
 #include <malloc.h>
+#include <mapmem.h>
 #include <sort.h>
 
+const efi_guid_t efi_guid_capsule_report = EFI_CAPSULE_REPORT_GUID;
+
+/* for file system access */
+static struct efi_file_handle *bootdev_root;
+
 /*
  * Launch a capsule
  */
@@ -96,3 +102,545 @@ efi_status_t EFIAPI efi_query_capsule_caps(
 out:
 	return EFI_EXIT(ret);
 }
+
+#ifdef CONFIG_EFI_CAPSULE_ON_DISK
+static void efi_capsule_result_variable(int num,
+					struct efi_capsule_header *capsule,
+					efi_status_t return_status)
+{
+	char variable_name[12];
+	u16 variable_name16[12], *p;
+	struct efi_capsule_result_variable_header result;
+	struct efi_time time;
+	efi_status_t ret;
+
+	sprintf(variable_name, "Capsule%04X", num);
+	p = variable_name16;
+	utf8_utf16_strncpy(&p, variable_name, 11);
+	result.variable_total_size = sizeof(result);
+	result.capsule_guid = capsule->capsule_guid;
+	ret = EFI_CALL((*efi_runtime_services.get_time)(&time, NULL));
+	if (ret == EFI_SUCCESS)
+		memcpy(&result.capsule_processed, &time, sizeof(time));
+	else
+		memset(&result.capsule_processed, 0, sizeof(time));
+	result.capsule_status = return_status;
+	ret = EFI_CALL(efi_set_variable(variable_name16,
+					&efi_guid_capsule_report,
+					EFI_VARIABLE_NON_VOLATILE |
+					EFI_VARIABLE_BOOTSERVICE_ACCESS |
+					EFI_VARIABLE_RUNTIME_ACCESS,
+					sizeof(result), &result));
+	if (ret)
+		EFI_PRINT("EFI Capsule: creating %s failed\n", variable_name);
+}
+
+static efi_status_t get_dp_device(u16 *boot_var,
+				  struct efi_device_path **device_dp)
+{
+	void *buf = NULL;
+	efi_uintn_t size;
+	struct efi_load_option lo;
+	struct efi_device_path *file_dp;
+	efi_status_t ret;
+
+	size = 0;
+	ret = EFI_CALL(efi_get_variable(boot_var, &efi_global_variable_guid,
+					NULL, &size, NULL));
+	if (ret == EFI_BUFFER_TOO_SMALL) {
+		buf = malloc(size);
+		if (!buf)
+			return EFI_OUT_OF_RESOURCES;
+		ret = EFI_CALL(efi_get_variable(boot_var,
+						&efi_global_variable_guid,
+						NULL, &size, buf));
+	}
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	efi_deserialize_load_option(&lo, buf);
+
+	if (lo.attributes & LOAD_OPTION_ACTIVE) {
+		efi_dp_split_file_path(lo.file_path, device_dp, &file_dp);
+		efi_free_pool(file_dp);
+
+		ret = EFI_SUCCESS;
+	} else {
+		ret = EFI_NOT_FOUND;
+	}
+
+	free(buf);
+
+	return ret;
+}
+
+static bool device_is_present(struct efi_device_path *dp)
+{
+	efi_handle_t handle;
+	struct efi_handler *handler;
+	efi_status_t ret;
+
+	handle = efi_dp_find_obj(dp, NULL);
+	if (!handle)
+		return false;
+
+	/* check if this is a block device */
+	ret = efi_search_protocol(handle, &efi_block_io_guid, &handler);
+	if (ret != EFI_SUCCESS)
+		return false;
+
+	return true;
+}
+
+static efi_status_t find_boot_device(void)
+{
+	char boot_var[9];
+	u16 boot_var16[9], *p, bootnext, *boot_order = NULL;
+	efi_uintn_t size;
+	int i, num;
+	struct efi_simple_file_system_protocol *volume;
+	struct efi_device_path *boot_dev = NULL;
+	efi_status_t ret;
+
+	/* find active boot device in BootNext */
+	bootnext = 0;
+	size = sizeof(bootnext);
+	ret = EFI_CALL(efi_get_variable(L"BootNext",
+					(efi_guid_t *)&efi_global_variable_guid,
+					NULL, &size, &bootnext));
+	if (ret == EFI_SUCCESS || ret == EFI_BUFFER_TOO_SMALL) {
+		/* BootNext does exist here */
+		if (ret == EFI_BUFFER_TOO_SMALL || size != sizeof(u16)) {
+			printf("BootNext must be 16-bit integer\n");
+			goto skip;
+		}
+		sprintf((char *)boot_var, "Boot%04X", bootnext);
+		p = boot_var16;
+		utf8_utf16_strcpy(&p, boot_var);
+
+		ret = get_dp_device(boot_var16, &boot_dev);
+		if (ret == EFI_SUCCESS) {
+			if (device_is_present(boot_dev)) {
+				goto out;
+			} else {
+				efi_free_pool(boot_dev);
+				boot_dev = NULL;
+			}
+		}
+	}
+
+skip:
+	/* find active boot device in BootOrder */
+	size = 0;
+	ret = EFI_CALL(efi_get_variable(L"BootOrder", &efi_global_variable_guid,
+					NULL, &size, NULL));
+	if (ret == EFI_BUFFER_TOO_SMALL) {
+		boot_order = malloc(size);
+		if (!boot_order) {
+			ret = EFI_OUT_OF_RESOURCES;
+			goto out;
+		}
+
+		ret = EFI_CALL(efi_get_variable(
+					L"BootOrder", &efi_global_variable_guid,
+					NULL, &size, boot_order));
+	}
+	if (ret != EFI_SUCCESS)
+		goto out;
+
+	/* check in higher order */
+	num = size / sizeof(u16);
+	for (i = 0; i < num; i++) {
+		sprintf((char *)boot_var, "Boot%04X", boot_order[i]);
+		p = boot_var16;
+		utf8_utf16_strcpy(&p, boot_var);
+		ret = get_dp_device(boot_var16, &boot_dev);
+		if (ret != EFI_SUCCESS)
+			continue;
+
+		if (device_is_present(boot_dev))
+			break;
+
+		efi_free_pool(boot_dev);
+		boot_dev = NULL;
+	}
+out:
+	if (boot_dev) {
+		u16 *path_str;
+
+		path_str = efi_dp_str(boot_dev);
+		EFI_PRINT("EFI Capsule: bootdev is %ls\n", path_str);
+		efi_free_pool(path_str);
+
+		volume = efi_fs_from_path(boot_dev);
+		if (!volume)
+			ret = EFI_DEVICE_ERROR;
+		else
+			ret = EFI_CALL(volume->open_volume(volume,
+							   &bootdev_root));
+		efi_free_pool(boot_dev);
+	} else {
+		ret = EFI_NOT_FOUND;
+	}
+	free(boot_order);
+
+	return ret;
+}
+
+/*
+ * Traverse a capsule directory in boot device
+ * Called by initialization code, and returns an array of capsule file
+ * names in @files
+ */
+static efi_status_t efi_capsule_scan_dir(u16 ***files, int *num)
+{
+	struct efi_file_handle *dirh;
+	struct efi_file_info *dirent;
+	efi_uintn_t dirent_size, tmp_size;
+	int count;
+	u16 **tmp_files;
+	efi_status_t ret;
+
+	ret = find_boot_device();
+	if (ret == EFI_NOT_FOUND) {
+		EFI_PRINT("EFI Capsule: bootdev is not set\n");
+		*num = 0;
+		return EFI_SUCCESS;
+	} else if (ret != EFI_SUCCESS) {
+		return EFI_DEVICE_ERROR;
+	}
+
+	/* count capsule files */
+	ret = EFI_CALL((*bootdev_root->open)(bootdev_root, &dirh,
+					     EFI_CAPSULE_DIR,
+					     EFI_FILE_MODE_READ, 0));
+	if (ret != EFI_SUCCESS) {
+		*num = 0;
+		return EFI_SUCCESS;
+	}
+
+	dirent_size = 256;
+	dirent = malloc(dirent_size);
+	if (!dirent)
+		return EFI_OUT_OF_RESOURCES;
+
+	count = 0;
+	while (1) {
+		tmp_size = dirent_size;
+		ret = EFI_CALL((*dirh->read)(dirh, &tmp_size, dirent));
+		if (ret == EFI_BUFFER_TOO_SMALL) {
+			dirent = realloc(dirent, tmp_size);
+			if (!dirent) {
+				ret = EFI_OUT_OF_RESOURCES;
+				goto err;
+			}
+			dirent_size = tmp_size;
+			ret = EFI_CALL((*dirh->read)(dirh, &tmp_size, dirent));
+		}
+		if (ret != EFI_SUCCESS)
+			goto err;
+		if (!tmp_size)
+			break;
+
+		if (!(dirent->attribute & EFI_FILE_DIRECTORY) &&
+		    u16_strcmp(dirent->file_name, L".") &&
+		    u16_strcmp(dirent->file_name, L".."))
+			count++;
+	}
+
+	ret = EFI_CALL((*dirh->setpos)(dirh, 0));
+	if (ret != EFI_SUCCESS)
+		goto err;
+
+	/* make a list */
+	tmp_files = malloc(count * sizeof(*files));
+	if (!tmp_files) {
+		ret = EFI_OUT_OF_RESOURCES;
+		goto err;
+	}
+
+	count = 0;
+	while (1) {
+		tmp_size = dirent_size;
+		ret = EFI_CALL((*dirh->read)(dirh, &tmp_size, dirent));
+		if (ret != EFI_SUCCESS)
+			goto err;
+		if (!tmp_size)
+			break;
+
+		if (!(dirent->attribute & EFI_FILE_DIRECTORY) &&
+		    u16_strcmp(dirent->file_name, L".") &&
+		    u16_strcmp(dirent->file_name, L".."))
+			tmp_files[count++] = u16_strdup(dirent->file_name);
+	}
+	/* ignore an error */
+	EFI_CALL((*dirh->close)(dirh));
+
+	/* in ascii order */
+	/* FIXME: u16 version of strcasecmp */
+	qsort(tmp_files, count, sizeof(*tmp_files),
+	      (int (*)(const void *, const void *))strcasecmp);
+	*files = tmp_files;
+	*num = count;
+	ret = EFI_SUCCESS;
+err:
+	free(dirent);
+
+	return ret;
+}
+
+/*
+ * Read in a capsule file
+ */
+static efi_status_t efi_capsule_read_file(u16 *filename,
+					  struct efi_capsule_header **capsule)
+{
+	struct efi_file_handle *dirh, *fh;
+	struct efi_file_info *file_info = NULL;
+	struct efi_capsule_header *buf = NULL;
+	efi_uintn_t size;
+	efi_status_t ret;
+
+	ret = EFI_CALL((*bootdev_root->open)(bootdev_root, &dirh,
+					     EFI_CAPSULE_DIR,
+					     EFI_FILE_MODE_READ, 0));
+	if (ret != EFI_SUCCESS)
+		return ret;
+	ret = EFI_CALL((*dirh->open)(dirh, &fh, filename,
+				     EFI_FILE_MODE_READ, 0));
+	/* ignore an error */
+	EFI_CALL((*dirh->close)(dirh));
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	/* file size */
+	size = 0;
+	ret = EFI_CALL((*fh->getinfo)(fh, &efi_file_info_guid,
+				      &size, file_info));
+	if (ret == EFI_BUFFER_TOO_SMALL) {
+		file_info = malloc(size);
+		if (!file_info) {
+			ret = EFI_OUT_OF_RESOURCES;
+			goto err;
+		}
+		ret = EFI_CALL((*fh->getinfo)(fh, &efi_file_info_guid,
+					      &size, file_info));
+	}
+	if (ret != EFI_SUCCESS)
+		goto err;
+	size = file_info->file_size;
+	free(file_info);
+	buf = malloc(size);
+	if (!buf) {
+		ret = EFI_OUT_OF_RESOURCES;
+		goto err;
+	}
+
+	/* fetch data */
+	ret = EFI_CALL((*fh->read)(fh, &size, buf));
+	if (ret == EFI_SUCCESS) {
+		if (size >= buf->capsule_image_size) {
+			*capsule = buf;
+		} else {
+			free(buf);
+			ret = EFI_INVALID_PARAMETER;
+		}
+	} else {
+		free(buf);
+	}
+err:
+	EFI_CALL((*fh->close)(fh));
+
+	return ret;
+}
+
+static efi_status_t efi_capsule_delete_file(u16 *filename)
+{
+	struct efi_file_handle *dirh, *fh;
+	efi_status_t ret;
+
+	ret = EFI_CALL((*bootdev_root->open)(bootdev_root, &dirh,
+					     EFI_CAPSULE_DIR,
+					     EFI_FILE_MODE_READ, 0));
+	if (ret != EFI_SUCCESS)
+		return ret;
+	ret = EFI_CALL((*dirh->open)(dirh, &fh, filename,
+				     EFI_FILE_MODE_READ, 0));
+	/* ignore an error */
+	EFI_CALL((*dirh->close)(dirh));
+
+	ret = EFI_CALL((*fh->delete)(fh));
+
+	return ret;
+}
+
+static void efi_capsule_scan_done(void)
+{
+	EFI_CALL((*bootdev_root->close)(bootdev_root));
+	bootdev_root = NULL;
+}
+
+efi_status_t __weak arch_efi_load_capsule_drivers(void)
+{
+	return EFI_SUCCESS;
+}
+
+static int get_last_capsule(void)
+{
+	u16 value16[11]; /* "CapsuleXXXX": non-null-terminated */
+	char value[11], *p;
+	efi_uintn_t size;
+	unsigned long num = 0xffff;
+	efi_status_t ret;
+
+	size = sizeof(value16);
+	ret = EFI_CALL(efi_get_variable(L"CapsuleLast",
+					&efi_guid_capsule_report,
+					NULL, &size, value16));
+	if (ret != EFI_SUCCESS || u16_strncmp(value16, L"Capsule", 7))
+		goto err;
+
+	p = value;
+	utf16_utf8_strcpy(&p, value16);
+	strict_strtoul(&value[7], 16, &num);
+err:
+	return (int)num;
+}
+
+/*
+ * Launch all the capsules in system at boot time
+ *
+ * Called by efi init code
+ */
+efi_status_t efi_launch_capsules(void)
+{
+	struct efi_capsule_header *capsule = NULL;
+	u16 **files;
+	int nfiles, num, i;
+	char variable_name[12];
+	u16 variable_name16[12], *p;
+	efi_status_t ret;
+
+	num = get_last_capsule();
+
+	/* Load capsule drivers */
+	ret = arch_efi_load_capsule_drivers();
+	if (ret != EFI_SUCCESS)
+		return ret;
+
+	/*
+	 * Find capsules on disk.
+	 * All the capsules are collected at the beginning because
+	 * capsule files will be removed instantly.
+	 */
+	nfiles = 0;
+	files = NULL;
+	ret = efi_capsule_scan_dir(&files, &nfiles);
+	if (ret != EFI_SUCCESS)
+		return ret;
+	if (!nfiles)
+		return EFI_SUCCESS;
+
+	/* Launch capsules */
+	for (i = 0, ++num; i < nfiles; i++, num++) {
+		EFI_PRINT("EFI Capsule from %ls ...\n", files[i]);
+		if (num > 0xffff)
+			num = 0;
+		ret = efi_capsule_read_file(files[i], &capsule);
+		if (ret == EFI_SUCCESS) {
+			ret = EFI_CALL(efi_update_capsule(&capsule, 1, 0));
+			if (ret != EFI_SUCCESS)
+				EFI_PRINT("EFI Capsule update failed at %ls\n",
+					  files[i]);
+
+			free(capsule);
+		} else {
+			EFI_PRINT("EFI Capsule read failed\n");
+		}
+		/* create CapsuleXXXX */
+		efi_capsule_result_variable(num, capsule, ret);
+
+		/* delete a capsule either in case of success or failure */
+		ret = efi_capsule_delete_file(files[i]);
+		if (ret != EFI_SUCCESS)
+			EFI_PRINT("EFI Capsule deletion of capsule failed at %ls\n",
+				  files[i]);
+	}
+	efi_capsule_scan_done();
+
+	for (i = 0; i < nfiles; i++)
+		free(files[i]);
+	free(files);
+
+	/* CapsuleMax */
+	p = variable_name16;
+	utf8_utf16_strncpy(&p, "CapsuleFFFF", 11);
+	EFI_CALL(efi_set_variable(L"CapsuleMax", &efi_guid_capsule_report,
+				  EFI_VARIABLE_BOOTSERVICE_ACCESS |
+				  EFI_VARIABLE_RUNTIME_ACCESS,
+				  22, variable_name16));
+
+	/* CapsuleLast */
+	sprintf(variable_name, "Capsule%04X", num - 1);
+	p = variable_name16;
+	utf8_utf16_strncpy(&p, variable_name, 11);
+	EFI_CALL(efi_set_variable(L"CapsuleLast", &efi_guid_capsule_report,
+				  EFI_VARIABLE_NON_VOLATILE |
+				  EFI_VARIABLE_BOOTSERVICE_ACCESS |
+				  EFI_VARIABLE_RUNTIME_ACCESS,
+				  22, variable_name16));
+
+	return ret;
+}
+
+/*
+ * Dummy functions after ExitBootServices()
+ */
+efi_status_t EFIAPI efi_update_capsule_runtime(
+		struct efi_capsule_header **capsule_header_array,
+		efi_uintn_t capsule_count,
+		u64 scatter_gather_list)
+{
+	return EFI_UNSUPPORTED;
+}
+
+efi_status_t EFIAPI efi_query_capsule_caps_runtime(
+		struct efi_capsule_header **capsule_header_array,
+		efi_uintn_t capsule_count,
+		u64 *maximum_capsule_size,
+		u32 *reset_type)
+{
+	return EFI_UNSUPPORTED;
+}
+
+/**
+ * efi_capsule_boot_exit_notify() - notify ExitBootServices() is called
+ */
+void efi_capsule_boot_exit_notify(void)
+{
+	efi_runtime_services.update_capsule = efi_update_capsule_runtime;
+	efi_runtime_services.query_capsule_caps =
+				efi_query_capsule_caps_runtime;
+	efi_update_table_header_crc32(&efi_runtime_services.hdr);
+}
+#else
+/*
+ * Dummy functions for runtime services
+ */
+efi_status_t EFIAPI efi_update_capsule(
+		struct efi_capsule_header **capsule_header_array,
+		efi_uintn_t capsule_count,
+		u64 scatter_gather_list)
+{
+	return EFI_UNSUPPORTED;
+}
+
+efi_status_t EFIAPI efi_query_capsule_caps(
+		struct efi_capsule_header **capsule_header_array,
+		efi_uintn_t capsule_count,
+		u64 *maximum_capsule_size,
+		u32 *reset_type)
+{
+	return EFI_UNSUPPORTED;
+}
+#endif /* CONFIG_EFI_CAPSULE_ON_DISK */
diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c
index c485cad34022..309defc5e40d 100644
--- a/lib/efi_loader/efi_setup.c
+++ b/lib/efi_loader/efi_setup.c
@@ -96,6 +96,10 @@ static efi_status_t efi_init_os_indications(void)
 #ifdef CONFIG_EFI_CAPSULE_UPDATE
 	os_indications_supported |=
 			EFI_OS_INDICATIONS_CAPSULE_RESULT_VAR_SUPPORTED;
+#endif
+#ifdef CONFIG_EFI_CAPSULE_ON_DISK
+	os_indications_supported |=
+			EFI_OS_INDICATIONS_FILE_CAPSULE_DELIVERY_SUPPORTED;
 #endif
 	return EFI_CALL(efi_set_variable(L"OsIndicationsSupported",
 					 &efi_global_variable_guid,
@@ -196,6 +200,8 @@ efi_status_t efi_init_obj_list(void)
 	if (ret != EFI_SUCCESS)
 		goto out;
 
+	/* Execute capsules after reboot */
+	ret = efi_launch_capsules();
 out:
 	efi_obj_list_initialized = ret;
 	return ret;
-- 
2.25.1



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