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woocommerce/vendor/maxmind-db/reader/ext/maxminddb.c
naomi c46c7ddbf0 initial commit
2021-12-10 12:03:04 +00:00

705 lines
23 KiB
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/* MaxMind, Inc., licenses this file to you under the Apache License, Version
* 2.0 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
#include "php_maxminddb.h"
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <php.h>
#include <zend.h>
#include "Zend/zend_exceptions.h"
#include "ext/standard/info.h"
#include <maxminddb.h>
#ifdef ZTS
#include <TSRM.h>
#endif
#define __STDC_FORMAT_MACROS
#include <inttypes.h>
#define PHP_MAXMINDDB_NS ZEND_NS_NAME("MaxMind", "Db")
#define PHP_MAXMINDDB_READER_NS ZEND_NS_NAME(PHP_MAXMINDDB_NS, "Reader")
#define PHP_MAXMINDDB_READER_EX_NS \
ZEND_NS_NAME(PHP_MAXMINDDB_READER_NS, "InvalidDatabaseException")
#ifdef ZEND_ENGINE_3
#define Z_MAXMINDDB_P(zv) php_maxminddb_fetch_object(Z_OBJ_P(zv))
#define _ZVAL_STRING ZVAL_STRING
#define _ZVAL_STRINGL ZVAL_STRINGL
typedef size_t strsize_t;
typedef zend_object free_obj_t;
#else
#define Z_MAXMINDDB_P(zv) \
(maxminddb_obj *)zend_object_store_get_object(zv TSRMLS_CC)
#define _ZVAL_STRING(a, b) ZVAL_STRING(a, b, 1)
#define _ZVAL_STRINGL(a, b, c) ZVAL_STRINGL(a, b, c, 1)
typedef int strsize_t;
typedef void free_obj_t;
#endif
/* For PHP 8 compatibility */
#ifndef TSRMLS_C
#define TSRMLS_C
#endif
#ifndef TSRMLS_CC
#define TSRMLS_CC
#endif
#ifndef TSRMLS_DC
#define TSRMLS_DC
#endif
#ifndef ZEND_ACC_CTOR
#define ZEND_ACC_CTOR 0
#endif
#ifdef ZEND_ENGINE_3
typedef struct _maxminddb_obj {
MMDB_s *mmdb;
zend_object std;
} maxminddb_obj;
#else
typedef struct _maxminddb_obj {
zend_object std;
MMDB_s *mmdb;
} maxminddb_obj;
#endif
PHP_FUNCTION(maxminddb);
static int
get_record(INTERNAL_FUNCTION_PARAMETERS, zval *record, int *prefix_len);
static const MMDB_entry_data_list_s *
handle_entry_data_list(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC);
static const MMDB_entry_data_list_s *
handle_array(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC);
static const MMDB_entry_data_list_s *
handle_map(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC);
static void handle_uint128(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC);
static void handle_uint64(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC);
static void handle_uint32(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC);
static zend_class_entry *lookup_class(const char *name TSRMLS_DC);
#define CHECK_ALLOCATED(val) \
if (!val) { \
zend_error(E_ERROR, "Out of memory"); \
return; \
}
#define THROW_EXCEPTION(name, ...) \
{ \
zend_class_entry *exception_ce = lookup_class(name TSRMLS_CC); \
zend_throw_exception_ex(exception_ce, 0 TSRMLS_CC, __VA_ARGS__); \
}
#if PHP_VERSION_ID < 50399
#define object_properties_init(zo, class_type) \
{ \
zval *tmp; \
zend_hash_copy((*zo).properties, \
&class_type->default_properties, \
(copy_ctor_func_t)zval_add_ref, \
(void *)&tmp, \
sizeof(zval *)); \
}
#endif
static zend_object_handlers maxminddb_obj_handlers;
static zend_class_entry *maxminddb_ce;
static inline maxminddb_obj *
php_maxminddb_fetch_object(zend_object *obj TSRMLS_DC) {
#ifdef ZEND_ENGINE_3
return (maxminddb_obj *)((char *)(obj)-XtOffsetOf(maxminddb_obj, std));
#else
return (maxminddb_obj *)obj;
#endif
}
ZEND_BEGIN_ARG_INFO_EX(arginfo_maxmindbreader_construct, 0, 0, 1)
ZEND_ARG_INFO(0, db_file)
ZEND_END_ARG_INFO()
PHP_METHOD(MaxMind_Db_Reader, __construct) {
char *db_file = NULL;
strsize_t name_len;
zval *_this_zval = NULL;
if (zend_parse_method_parameters(ZEND_NUM_ARGS() TSRMLS_CC,
getThis(),
"Os",
&_this_zval,
maxminddb_ce,
&db_file,
&name_len) == FAILURE) {
THROW_EXCEPTION("InvalidArgumentException",
"The constructor takes exactly one argument.");
return;
}
if (0 != php_check_open_basedir(db_file TSRMLS_CC) ||
0 != access(db_file, R_OK)) {
THROW_EXCEPTION("InvalidArgumentException",
"The file \"%s\" does not exist or is not readable.",
db_file);
return;
}
MMDB_s *mmdb = (MMDB_s *)ecalloc(1, sizeof(MMDB_s));
uint16_t status = MMDB_open(db_file, MMDB_MODE_MMAP, mmdb);
if (MMDB_SUCCESS != status) {
THROW_EXCEPTION(PHP_MAXMINDDB_READER_EX_NS,
"Error opening database file (%s). Is this a valid "
"MaxMind DB file?",
db_file);
efree(mmdb);
return;
}
maxminddb_obj *mmdb_obj = Z_MAXMINDDB_P(getThis());
mmdb_obj->mmdb = mmdb;
}
ZEND_BEGIN_ARG_INFO_EX(arginfo_maxmindbreader_get, 0, 0, 1)
ZEND_ARG_INFO(0, ip_address)
ZEND_END_ARG_INFO()
PHP_METHOD(MaxMind_Db_Reader, get) {
int prefix_len = 0;
get_record(INTERNAL_FUNCTION_PARAM_PASSTHRU, return_value, &prefix_len);
}
PHP_METHOD(MaxMind_Db_Reader, getWithPrefixLen) {
zval *record, *z_prefix_len;
#ifdef ZEND_ENGINE_3
zval _record, _z_prefix_len;
record = &_record;
z_prefix_len = &_z_prefix_len;
#else
ALLOC_INIT_ZVAL(record);
ALLOC_INIT_ZVAL(z_prefix_len);
#endif
int prefix_len = 0;
if (get_record(INTERNAL_FUNCTION_PARAM_PASSTHRU, record, &prefix_len)) {
return;
}
array_init(return_value);
add_next_index_zval(return_value, record);
ZVAL_LONG(z_prefix_len, prefix_len);
add_next_index_zval(return_value, z_prefix_len);
}
static int
get_record(INTERNAL_FUNCTION_PARAMETERS, zval *record, int *prefix_len) {
char *ip_address = NULL;
strsize_t name_len;
zval *_this_zval = NULL;
if (zend_parse_method_parameters(ZEND_NUM_ARGS() TSRMLS_CC,
getThis(),
"Os",
&_this_zval,
maxminddb_ce,
&ip_address,
&name_len) == FAILURE) {
THROW_EXCEPTION("InvalidArgumentException",
"Method takes exactly one argument.");
return 1;
}
const maxminddb_obj *mmdb_obj = (maxminddb_obj *)Z_MAXMINDDB_P(getThis());
MMDB_s *mmdb = mmdb_obj->mmdb;
if (NULL == mmdb) {
THROW_EXCEPTION("BadMethodCallException",
"Attempt to read from a closed MaxMind DB.");
return 1;
}
struct addrinfo hints = {
.ai_family = AF_UNSPEC,
.ai_flags = AI_NUMERICHOST,
// We set ai_socktype so that we only get one result back
.ai_socktype = SOCK_STREAM};
struct addrinfo *addresses = NULL;
int gai_status = getaddrinfo(ip_address, NULL, &hints, &addresses);
if (gai_status) {
THROW_EXCEPTION("InvalidArgumentException",
"The value \"%s\" is not a valid IP address.",
ip_address);
return 1;
}
if (!addresses || !addresses->ai_addr) {
THROW_EXCEPTION(
"InvalidArgumentException",
"getaddrinfo was successful but failed to set the addrinfo");
return 1;
}
int sa_family = addresses->ai_addr->sa_family;
int mmdb_error = MMDB_SUCCESS;
MMDB_lookup_result_s result =
MMDB_lookup_sockaddr(mmdb, addresses->ai_addr, &mmdb_error);
freeaddrinfo(addresses);
if (MMDB_SUCCESS != mmdb_error) {
char *exception_name;
if (MMDB_IPV6_LOOKUP_IN_IPV4_DATABASE_ERROR == mmdb_error) {
exception_name = "InvalidArgumentException";
} else {
exception_name = PHP_MAXMINDDB_READER_EX_NS;
}
THROW_EXCEPTION(exception_name,
"Error looking up %s. %s",
ip_address,
MMDB_strerror(mmdb_error));
return 1;
}
*prefix_len = result.netmask;
if (sa_family == AF_INET && mmdb->metadata.ip_version == 6) {
// We return the prefix length given the IPv4 address. If there is
// no IPv4 subtree, we return a prefix length of 0.
*prefix_len = *prefix_len >= 96 ? *prefix_len - 96 : 0;
}
if (!result.found_entry) {
ZVAL_NULL(record);
return 0;
}
MMDB_entry_data_list_s *entry_data_list = NULL;
int status = MMDB_get_entry_data_list(&result.entry, &entry_data_list);
if (MMDB_SUCCESS != status) {
THROW_EXCEPTION(PHP_MAXMINDDB_READER_EX_NS,
"Error while looking up data for %s. %s",
ip_address,
MMDB_strerror(status));
MMDB_free_entry_data_list(entry_data_list);
return 1;
} else if (NULL == entry_data_list) {
THROW_EXCEPTION(PHP_MAXMINDDB_READER_EX_NS,
"Error while looking up data for %s. Your database may "
"be corrupt or you have found a bug in libmaxminddb.",
ip_address);
return 1;
}
handle_entry_data_list(entry_data_list, record TSRMLS_CC);
MMDB_free_entry_data_list(entry_data_list);
return 0;
}
ZEND_BEGIN_ARG_INFO_EX(arginfo_maxmindbreader_void, 0, 0, 0)
ZEND_END_ARG_INFO()
PHP_METHOD(MaxMind_Db_Reader, metadata) {
if (ZEND_NUM_ARGS() != 0) {
THROW_EXCEPTION("InvalidArgumentException",
"Method takes no arguments.");
return;
}
const maxminddb_obj *const mmdb_obj =
(maxminddb_obj *)Z_MAXMINDDB_P(getThis());
if (NULL == mmdb_obj->mmdb) {
THROW_EXCEPTION("BadMethodCallException",
"Attempt to read from a closed MaxMind DB.");
return;
}
const char *const name = ZEND_NS_NAME(PHP_MAXMINDDB_READER_NS, "Metadata");
zend_class_entry *metadata_ce = lookup_class(name TSRMLS_CC);
object_init_ex(return_value, metadata_ce);
#ifdef ZEND_ENGINE_3
zval _metadata_array;
zval *metadata_array = &_metadata_array;
ZVAL_NULL(metadata_array);
#else
zval *metadata_array;
ALLOC_INIT_ZVAL(metadata_array);
#endif
MMDB_entry_data_list_s *entry_data_list;
MMDB_get_metadata_as_entry_data_list(mmdb_obj->mmdb, &entry_data_list);
handle_entry_data_list(entry_data_list, metadata_array TSRMLS_CC);
MMDB_free_entry_data_list(entry_data_list);
#if PHP_VERSION_ID >= 80000
zend_call_method_with_1_params(Z_OBJ_P(return_value),
metadata_ce,
&metadata_ce->constructor,
ZEND_CONSTRUCTOR_FUNC_NAME,
NULL,
metadata_array);
zval_ptr_dtor(metadata_array);
#elif defined(ZEND_ENGINE_3)
zend_call_method_with_1_params(return_value,
metadata_ce,
&metadata_ce->constructor,
ZEND_CONSTRUCTOR_FUNC_NAME,
NULL,
metadata_array);
zval_ptr_dtor(metadata_array);
#else
zend_call_method_with_1_params(&return_value,
metadata_ce,
&metadata_ce->constructor,
ZEND_CONSTRUCTOR_FUNC_NAME,
NULL,
metadata_array);
zval_ptr_dtor(&metadata_array);
#endif
}
PHP_METHOD(MaxMind_Db_Reader, close) {
if (ZEND_NUM_ARGS() != 0) {
THROW_EXCEPTION("InvalidArgumentException",
"Method takes no arguments.");
return;
}
maxminddb_obj *mmdb_obj = (maxminddb_obj *)Z_MAXMINDDB_P(getThis());
if (NULL == mmdb_obj->mmdb) {
THROW_EXCEPTION("BadMethodCallException",
"Attempt to close a closed MaxMind DB.");
return;
}
MMDB_close(mmdb_obj->mmdb);
efree(mmdb_obj->mmdb);
mmdb_obj->mmdb = NULL;
}
static const MMDB_entry_data_list_s *
handle_entry_data_list(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC) {
switch (entry_data_list->entry_data.type) {
case MMDB_DATA_TYPE_MAP:
return handle_map(entry_data_list, z_value TSRMLS_CC);
case MMDB_DATA_TYPE_ARRAY:
return handle_array(entry_data_list, z_value TSRMLS_CC);
case MMDB_DATA_TYPE_UTF8_STRING:
_ZVAL_STRINGL(z_value,
(char *)entry_data_list->entry_data.utf8_string,
entry_data_list->entry_data.data_size);
break;
case MMDB_DATA_TYPE_BYTES:
_ZVAL_STRINGL(z_value,
(char *)entry_data_list->entry_data.bytes,
entry_data_list->entry_data.data_size);
break;
case MMDB_DATA_TYPE_DOUBLE:
ZVAL_DOUBLE(z_value, entry_data_list->entry_data.double_value);
break;
case MMDB_DATA_TYPE_FLOAT:
ZVAL_DOUBLE(z_value, entry_data_list->entry_data.float_value);
break;
case MMDB_DATA_TYPE_UINT16:
ZVAL_LONG(z_value, entry_data_list->entry_data.uint16);
break;
case MMDB_DATA_TYPE_UINT32:
handle_uint32(entry_data_list, z_value TSRMLS_CC);
break;
case MMDB_DATA_TYPE_BOOLEAN:
ZVAL_BOOL(z_value, entry_data_list->entry_data.boolean);
break;
case MMDB_DATA_TYPE_UINT64:
handle_uint64(entry_data_list, z_value TSRMLS_CC);
break;
case MMDB_DATA_TYPE_UINT128:
handle_uint128(entry_data_list, z_value TSRMLS_CC);
break;
case MMDB_DATA_TYPE_INT32:
ZVAL_LONG(z_value, entry_data_list->entry_data.int32);
break;
default:
THROW_EXCEPTION(PHP_MAXMINDDB_READER_EX_NS,
"Invalid data type arguments: %d",
entry_data_list->entry_data.type);
return NULL;
}
return entry_data_list;
}
static const MMDB_entry_data_list_s *
handle_map(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC) {
array_init(z_value);
const uint32_t map_size = entry_data_list->entry_data.data_size;
uint i;
for (i = 0; i < map_size && entry_data_list; i++) {
entry_data_list = entry_data_list->next;
char *key = estrndup((char *)entry_data_list->entry_data.utf8_string,
entry_data_list->entry_data.data_size);
if (NULL == key) {
THROW_EXCEPTION(PHP_MAXMINDDB_READER_EX_NS,
"Invalid data type arguments");
return NULL;
}
entry_data_list = entry_data_list->next;
#ifdef ZEND_ENGINE_3
zval _new_value;
zval *new_value = &_new_value;
ZVAL_NULL(new_value);
#else
zval *new_value;
ALLOC_INIT_ZVAL(new_value);
#endif
entry_data_list =
handle_entry_data_list(entry_data_list, new_value TSRMLS_CC);
add_assoc_zval(z_value, key, new_value);
efree(key);
}
return entry_data_list;
}
static const MMDB_entry_data_list_s *
handle_array(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC) {
const uint32_t size = entry_data_list->entry_data.data_size;
array_init(z_value);
uint i;
for (i = 0; i < size && entry_data_list; i++) {
entry_data_list = entry_data_list->next;
#ifdef ZEND_ENGINE_3
zval _new_value;
zval *new_value = &_new_value;
ZVAL_NULL(new_value);
#else
zval *new_value;
ALLOC_INIT_ZVAL(new_value);
#endif
entry_data_list =
handle_entry_data_list(entry_data_list, new_value TSRMLS_CC);
add_next_index_zval(z_value, new_value);
}
return entry_data_list;
}
static void handle_uint128(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC) {
uint64_t high = 0;
uint64_t low = 0;
#if MMDB_UINT128_IS_BYTE_ARRAY
int i;
for (i = 0; i < 8; i++) {
high = (high << 8) | entry_data_list->entry_data.uint128[i];
}
for (i = 8; i < 16; i++) {
low = (low << 8) | entry_data_list->entry_data.uint128[i];
}
#else
high = entry_data_list->entry_data.uint128 >> 64;
low = (uint64_t)entry_data_list->entry_data.uint128;
#endif
char *num_str;
spprintf(&num_str, 0, "0x%016" PRIX64 "%016" PRIX64, high, low);
CHECK_ALLOCATED(num_str);
_ZVAL_STRING(z_value, num_str);
efree(num_str);
}
static void handle_uint32(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC) {
uint32_t val = entry_data_list->entry_data.uint32;
#if LONG_MAX >= UINT32_MAX
ZVAL_LONG(z_value, val);
return;
#else
if (val <= LONG_MAX) {
ZVAL_LONG(z_value, val);
return;
}
char *int_str;
spprintf(&int_str, 0, "%" PRIu32, val);
CHECK_ALLOCATED(int_str);
_ZVAL_STRING(z_value, int_str);
efree(int_str);
#endif
}
static void handle_uint64(const MMDB_entry_data_list_s *entry_data_list,
zval *z_value TSRMLS_DC) {
uint64_t val = entry_data_list->entry_data.uint64;
#if LONG_MAX >= UINT64_MAX
ZVAL_LONG(z_value, val);
return;
#else
if (val <= LONG_MAX) {
ZVAL_LONG(z_value, val);
return;
}
char *int_str;
spprintf(&int_str, 0, "%" PRIu64, val);
CHECK_ALLOCATED(int_str);
_ZVAL_STRING(z_value, int_str);
efree(int_str);
#endif
}
static zend_class_entry *lookup_class(const char *name TSRMLS_DC) {
#ifdef ZEND_ENGINE_3
zend_string *n = zend_string_init(name, strlen(name), 0);
zend_class_entry *ce = zend_lookup_class(n);
zend_string_release(n);
if (NULL == ce) {
zend_error(E_ERROR, "Class %s not found", name);
}
return ce;
#else
zend_class_entry **ce;
if (FAILURE == zend_lookup_class(name, strlen(name), &ce TSRMLS_CC)) {
zend_error(E_ERROR, "Class %s not found", name);
}
return *ce;
#endif
}
static void maxminddb_free_storage(free_obj_t *object TSRMLS_DC) {
maxminddb_obj *obj =
php_maxminddb_fetch_object((zend_object *)object TSRMLS_CC);
if (obj->mmdb != NULL) {
MMDB_close(obj->mmdb);
efree(obj->mmdb);
}
zend_object_std_dtor(&obj->std TSRMLS_CC);
#ifndef ZEND_ENGINE_3
efree(object);
#endif
}
#ifdef ZEND_ENGINE_3
static zend_object *maxminddb_create_handler(zend_class_entry *type TSRMLS_DC) {
maxminddb_obj *obj = (maxminddb_obj *)ecalloc(1, sizeof(maxminddb_obj));
zend_object_std_init(&obj->std, type TSRMLS_CC);
object_properties_init(&(obj->std), type);
obj->std.handlers = &maxminddb_obj_handlers;
return &obj->std;
}
#else
static zend_object_value
maxminddb_create_handler(zend_class_entry *type TSRMLS_DC) {
zend_object_value retval;
maxminddb_obj *obj = (maxminddb_obj *)ecalloc(1, sizeof(maxminddb_obj));
zend_object_std_init(&obj->std, type TSRMLS_CC);
object_properties_init(&(obj->std), type);
retval.handle = zend_objects_store_put(
obj, NULL, maxminddb_free_storage, NULL TSRMLS_CC);
retval.handlers = &maxminddb_obj_handlers;
return retval;
}
#endif
// clang-format off
static zend_function_entry maxminddb_methods[] = {
PHP_ME(MaxMind_Db_Reader, __construct, arginfo_maxmindbreader_construct,
ZEND_ACC_PUBLIC | ZEND_ACC_CTOR)
PHP_ME(MaxMind_Db_Reader, close, arginfo_maxmindbreader_void, ZEND_ACC_PUBLIC)
PHP_ME(MaxMind_Db_Reader, get, arginfo_maxmindbreader_get, ZEND_ACC_PUBLIC)
PHP_ME(MaxMind_Db_Reader, getWithPrefixLen, arginfo_maxmindbreader_get, ZEND_ACC_PUBLIC)
PHP_ME(MaxMind_Db_Reader, metadata, arginfo_maxmindbreader_void, ZEND_ACC_PUBLIC)
{ NULL, NULL, NULL }
};
// clang-format on
PHP_MINIT_FUNCTION(maxminddb) {
zend_class_entry ce;
INIT_CLASS_ENTRY(ce, PHP_MAXMINDDB_READER_NS, maxminddb_methods);
maxminddb_ce = zend_register_internal_class(&ce TSRMLS_CC);
maxminddb_ce->create_object = maxminddb_create_handler;
memcpy(&maxminddb_obj_handlers,
zend_get_std_object_handlers(),
sizeof(zend_object_handlers));
maxminddb_obj_handlers.clone_obj = NULL;
#ifdef ZEND_ENGINE_3
maxminddb_obj_handlers.offset = XtOffsetOf(maxminddb_obj, std);
maxminddb_obj_handlers.free_obj = maxminddb_free_storage;
#endif
zend_declare_class_constant_string(maxminddb_ce,
"MMDB_LIB_VERSION",
sizeof("MMDB_LIB_VERSION") - 1,
MMDB_lib_version() TSRMLS_CC);
return SUCCESS;
}
static PHP_MINFO_FUNCTION(maxminddb) {
php_info_print_table_start();
php_info_print_table_row(2, "MaxMind DB Reader", "enabled");
php_info_print_table_row(
2, "maxminddb extension version", PHP_MAXMINDDB_VERSION);
php_info_print_table_row(
2, "libmaxminddb library version", MMDB_lib_version());
php_info_print_table_end();
}
zend_module_entry maxminddb_module_entry = {STANDARD_MODULE_HEADER,
PHP_MAXMINDDB_EXTNAME,
NULL,
PHP_MINIT(maxminddb),
NULL,
NULL,
NULL,
PHP_MINFO(maxminddb),
PHP_MAXMINDDB_VERSION,
STANDARD_MODULE_PROPERTIES};
#ifdef COMPILE_DL_MAXMINDDB
ZEND_GET_MODULE(maxminddb)
#endif
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