Salesforce附带的PHP工具包已经过时，不应使用。最近有更多的fork / community项目（一个，两个）尝试实现现代PHP客户端，也许其中一个可以为你服务。

一种简单的解决方案是通过对元数据API的普通SOAP调用来检索SecuritySettings。API版本设置为的请求有效负载46.0应为

<?xml version="1.0" encoding="UTF-8"?>
<Package xmlns="http://soap.sforce.com/2006/04/metadata">
    <types>
        <members>Security</members>
        <name>Settings</name>
    </types>
    <version>46.0</version>
</Package>

响应看起来像这样（仅显示了相关部分，实际响应要大得多）

<?xml version="1.0" encoding="UTF-8"?>
<SecuritySettings xmlns="http://soap.sforce.com/2006/04/metadata">
    <networkAccess>
        <ipRanges>
            <description>...</description>
            <end>1.255.255.255</end>
            <start>0.0.0.0</start>
        </ipRanges>
    </networkAccess>
</SecuritySettings>

转换为PHP：

$wsdl = PUBLIC_PATH . '/wsdl-metadata.xml'; 
$apiVersion = 46.0;
$singlePackage = true;
$members = 'Security';
$name = 'Settings';

$params = new StdClass();
$params->retrieveRequest = new StdClass();
$params->retrieveRequest->apiVersion = $apiVersion;
$params->retrieveRequest->singlePackage = $singlePackage;
$params->retrieveRequest->unpackaged = new StdClass();
$params->retrieveRequest->unpackaged->version = $apiVersion;
$params->retrieveRequest->unpackaged->type = new stdClass();
$params->retrieveRequest->unpackaged->type->members = $members;
$params->retrieveRequest->unpackaged->type->name = $name;

$option = [
    'trace' => TRUE,
];
// Namespaces
$namespace = 'http://soap.sforce.com/2006/04/metadata';
$client = new SoapClient($wsdl, $option);

$header = new SoapHeader($namespace, "SessionHeader", array ('sessionId' => $token)); // NEED: access token
$client->__setSoapHeaders($header);
$client->__setLocation($serverUrl); // NEED: service endpoint URL
$serviceResult = $client->retrieve($params);

你需要提供访问令牌（$token）和服务端点（$serverUrl）。