Hide sensitive data in API Gateway Manager

Overview

The API Gateway enables you to remove sensitive content from messages monitored in the API Gateway Manager web console and traffic monitoring database. You can redact sensitive content message content types such as HTTP headers, JSON, XML, HTML form, and plain text.

For example, sensitive data such as user passwords or credit card details can be redacted from both request and response messages. This means that such sensitive data is only ever present in the API Gateway memory during message processing, and is never displayed onscreen or persisted to disk. This is shown in the following architecture diagram:

API Gateway redaction configuration

In the API Gateway configuration, message redaction rules are configured in the following XML file:

When the API Gateway configuration is loaded, this creates redactors for the specified message protocol and content. This XML-based configuration uses the following model:

<Redaction enabled=”true” provider="redactors">
    <JSONRedactor>...</JSONRedactor>
    <RawRedactor>...</RawRedactor>
    <XMLRedactor>...</XMLRedactor>
    <HTTPRedactor>...</HTTPRedactor>
    <FormRedactor>...</FormRedactor>
</Redaction >

During the transaction processing, for each traffic monitoring stream, a chain of redactors is created for redacting the received and sent data. Each redactor removes any sensitive data that it finds and passes the data for the next redactor for processing. The redacted content is then written to the traffic monitoring database.

Each redactor defines its supported content types in RedactMime child elements. For example, the following shows content types for a JSON redactor:

<JSONRedactor>
    <RedactMime mimeType="application/json"/>
    <RedactMime mimeType="text/json"/>
     ...
</JSONRedactor>

Enable redaction for an API Gateway

To enable redaction for an API Gateway instance, perform the following steps:

1. Copy the sample redaction configuration file from the following directory:

apigateway/samples/redaction/sample_redaction.xml

2. Copy to the following directory:

apigateway/groups/<group-name/<instance-name/conf/redaction.xml

3. Ensure that redaction is enabled in redaction.xml as follows:

<ConfigurationFragment> <Redaction enabled="true" provider="redactors"> ... </ConfigurationFragment>

4. You can customize this file to configure redactors for different message payloads (HTTP, JSON, HTML form, and plain text). This is described in the next sections.
5. Edit the following file:

apigateway/groups/<group-name/<instance-name/conf/service.xml

6. And add the following line at the end of the file:

<NetService provider="NetService"> ... <include file="$VINSTDIR/conf/redaction.xml"/> </NetService>

7. Restart the API Gateway instance.

Redact HTTP message content

You can redact any HTTP header or parameter value from the API Gateway message stream based on HTTP URLs specified in configuration. This applies to both HTTP requests and responses. The following shows a simple example configured in redaction.xml:

<HTTPRedactor>
   <HTTPURL value="/payment"/>
   <HTTPParam value="credit_card"/>
   <HTTPParam value="password"/>
   <HTTPHeader value="Authorization"/>
</HTTPRedactor>

This example specifies to remove the credit_card and password query string parameters and Authorization header from messages sent to and from the /payment URL.

<HTTPURL value="/secure_folder" match="exact"/>

<HTTPURL value="/creditcard/" match="prefix"/>

<HTTPURL value="/order/shiptoaddress"/>

<HTTPURL value="/ORDER/shiptoaddress"/>

GET /securefiles/ HTTP/1.1
Host:www.httpwatch.com
Authorization:Basic aHR0cHdhdGNoOmY=

<HTTPRedactor>
   <HTTPURL value="/securefiles/" match="exact"/>
   <HTTPHeader value="Authorization"/>
</HTTPRedactor>

GET /securefiles/ HTTP/1.1Host:www.httpwatch.com

Redact JSON message content

You can redact JSON content from a message by configuring a specific path to be removed. You can define a relative or absolute location for elements inside a JSON document. When you configure a specific path in the JSON redactor configuration, all elements found in that element are removed.The following general syntax is used to remove JSON content:

rule = path_seg [“.”path_seg]*
path_seg = wildcard/rel_wildcard/identifier/array_elem
array_elem = identifier ”[”wildcard/number“]”
identifier = char*
wildcard = “*”
rel_wildcard = “**”

The following simple examples show how this syntax works:

ca.b.c, a.*.c, a.**.c, **.b.c,**.b[0].c,**.b[*].c, *.b[0].*

This results in the following configuration model:

<JSONRedactor>
   <RedactMime mimeType="text/json"/>
    ...
   <JSONPath path="a.b.c"/>
   <JSONPath path="**.b[0].c"/>
</JSONRedactor>

<JSONRedactor>
   <RedactMime mimeType="application/json"/>
   <JSONPath path="**.subject[0].id"/>
</JSONRedactor>

authentication.subject[0].id
cert.subject[0].id
attribute.subject[0].id

{
   "access_token":"2YotnFZFEjr1zCsicMWpAA",
   "token_type":"example",
   "expires_in":3600,
   "refresh_token":"tGzv3JOkF0XG5Qx2TlKWIA",
   "example_parameter":"example_value"
}

<JSONRedactor>
    <RedactMime mimeType="application/json"/>
    <JSONPath path="**.access_token"/>
    <JSONPath path="**.refresh_token"/>     
</JSONRedactor>

{
  "access_token":null,
  "token_type":"example",
  "expires_in":3600,
  "refresh_token":null,
  "example_parameter":"example_value"
}

Redact XML message content

You can redact specific XML content from a message by configuring XML elements or attributes to be removed. The XML redactor removes sensitive data based on the document location. You candefine the locations to be removed using the fully qualified name of the redacted element.

For example, to redact all the children of an element named axway:sensitive_data , where xmlns:axway is axway.com/ , you can use the following syntax:

<XMLRedactedElement localname=”sensitive_data” namespace=”http://axway.com”
  redactionDisposition=”redactChildren”/>

You can specify the following XML redaction directives:

If you need to redact attributes of the specified node, you can configure this using XMLRedactedAttribute (child of XMLRedactedElement). XMLRedactedElement has two mandatory attributes, localname and namespace, which have the same meaning for XMLRedactedAttribute.

<XMLRedactor>
   <RedactMime mimeType="application/xml"/>
   <RedactMime mimeType="text/xml"/>
   <!--Remove children of a_namespace:a_name and some attributtes-->
   <XMLRedactedElement localname="a_name" namespace="a_namespace" 
     redactionDisposition="redactChildren">
     <XMLRedactedAttribute localname="an_attribute_name" namespace="an_attribute_namespace"/>
     <XMLRedactedAttribute localname="another_attribute_name" namespace="o"/>
   </XMLRedactedElement>
</XMLRedactor>

<XMLRedactor>
   <RedactMime mimeType="application/xml"/>
   <RedactMime mimeType="text/xml"/> 
   <!---Remove element b:a and all its descendants-->
   <XMLRedactedElement localname="a" namespace="b" redactionDisposition="redactElement"/>
</XMLRedactor>

<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns="http://www.w3.org/2003/05/soap-envelope">
 <Header>
  <Security xmlns="http://docs.oasis-open.org/wss/2004/01/
    oasis-200401-wss-wssecurity-secext-1.0.xsd">
    <UsernameToken>
      <Username>root</Username>
      <Password Type="http://docs.oasis-open.org/wss/2004/01/
         oasis-200401-wss-username-token-profile-1.0#PasswordDigest">EVfkjdkljla=
      </Password>
      <Nonce>tKUH8ab3Rokm4t6IAlgcdg9yaEw=</Nonce>
      <Created xmlns="http://docs.oasis-open.org/wss/2004/01/
         oasis-200401-wss-wssecurity-utility-1.0.xsd">2010-08-10T10:52:42Z
      </Created>
    </UsernameToken>
  </Security>
 </Header>
 <Body>
  <SomeRequest xmlns="http://example.ns.com/foo/bar" />
 </Body>
</Envelope>

<XMLRedactor>
    <RedactMime mimeType="text/xml" />
    <XMLRedactedElement localname="UsernameToken" 
        namespace="http://docs.oasis-open.org/wss/2004/01/
          oasis-200401-wss-wssecurity-secext-1.0.xsd
          "redactionDisposition="redactChildren">
    </XMLRedactedElement>
</XMLRedactor>

<?xml version="1.0" encoding="UTF-8"?>
<Envelope xmlns="http://www.w3.org/2003/05/soap-envelope">
 <Header>
  <Security xmlns="http://docs.oasis-open.org/wss/2004/01/
    oasis-200401-wss-wssecurity-secext-1.0.xsd">
      <UsernameToken></UsernameToken>
  </Security>
 </Header>
 <Body>
  <SomeRequest xmlns="http://example.ns.com/foo/bar" /> 
 </Body>
</Envelope>

Redact HTML form message content

You can redact the content of specific HTML form fields by configuring the fields to be removed. The following shows an example from redaction.xml:

<FormRedactor>
    <RedactMime mimeType="application/x-www-form-urlencoded"/>
    <FormField value="credit_card"/>
    <FormField value="phone_number"/>
</FormRedactor>

This example removes the contents of the credit_card and phone_number form fields from the message.

Supported HTML form content types are as follows:

• application/x-www-form-urlencoded
• multipart/formdata

Redact raw message content

You can redact specific plain text by configuring regular expressions to define content to be removed. The following shows a configuration example:

<RawRedactor>
     <RedactMime mimeType="text/plain"/>
     <Regex exp="creditcard\s*=\s*(\d{16})" redact="1" icase="true"/>
     <Regex exp="source:\b(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\b" redact="1,2" icase="true"/>
     <Regex exp="\d{16}" redact="0" icase="false" />

</RawRedactor>

In this configuration model, the Regex element includes the following attributes to define the redactor behavior:

<Regex exp="creditcard\s*=\s*(\d{16})" redact="1" icase="false"/>

<Regex exp="ccdigits:(\d{1,4})\.(\d{1,4})\.(\d{1,4})\.(\d{1,4})" redact="1,2,3" icase="false"/>

<Regex exp="creditcard\s*=\s*(\d{16})" redact="1" icase="true"/>

Redact sensitive data from log files

For details on how to redact sensitive data from domain audit log and access log files, see the following topics:

• Configure API Gateway logging and events
• Transaction access log settings