Sunday, February 2, 2020

Anypoint Runtime Fabric - SSL Handshaking Troubleshooting

Introduction

Mulesoft's Anypoint Runtime Fabric is gaining momentum in the hybrid deployment model. Since version 1.4.1, the installation, configuration, and management have improved significantly. However, as it involves TLS/SSL, many things can go wrong. This article will provide some technical insights on how to diagnose those issues. In many cases, it may not be the configuration issues. Sometimes, the issues could be related to client code or network configuration. In later section, I have provided java code to test HTTPS REST API. First let's review the architecture of Anypoint Runtime Fabric.
As shown from the above diagram, the TLS/SSL is applied to all the controllers. Let's say the IP addresses are:
10.64.6.65
10.64.6.66
10.64.6.67
On all of the above controllers, the port 443 should be open. And we should be able to connect to all these controllers by using networking tools like nc, openssl, etc.

Verify Controller's TLS/SSL

First, from the client point of view, we need to make sure the port 443 is open and reachable. To do so, we can execute the following command:
$ nc -zv 10.64.6.65 443
Connection to 10.64.6.65 port 443 [tcp/https] succeeded!
As you can see, we can connect the port 443 successfully. nc is a very light and powerful tool for quickly scan the port of the server. Secondly, we can use openssl to verify the TLS/SSL:
$ openssl s_client -connect 10.64.6.65:443
openssl is a heavy weight tool. It can do a lot things, such as, connection verification, ssl certification generation and conversion, etc. The above command will print out information about the server's TLS/SSL certificates, ssh handshaking, cipher, etc. Here are an example:

$ openssl s_client -connect 10.64.6.65:443
CONNECTED(00000003)
depth=2 C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert High Assurance EV Root CA
verify return:1
depth=1 C = US, O = DigiCert Inc, OU = www.digicert.com, CN = DigiCert SHA2 High Assurance Server CA
verify return:1
depth=0 C = US, ST = Texas, L = Plano, O = "Keurig Dr. Pepper, Inc.", CN = *.gmcr.com
verify return:1
---
Certificate chain
 0 s:/C=US/ST=Texas/L=Plano/O=Keurig Dr. Pepper, Inc./CN=*.gmcr.com
   i:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert SHA2 High Assurance Server CA
 1 s:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert SHA2 High Assurance Server CA
   i:/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert High Assurance EV Root CA
---
Server certificate
-----BEGIN CERTIFICATE-----
...
-----END CERTIFICATE-----
subject=/C=US/ST=Texas/L=Plano/O=Keurig Dr. Pepper, Inc./CN=*.gmcr.com
issuer=/C=US/O=DigiCert Inc/OU=www.digicert.com/CN=DigiCert SHA2 High Assurance Server CA
---
No client certificate CA names sent
Server Temp Key: ECDH, X25519, 253 bits
---
SSL handshake has read 4087 bytes and written 289 bytes
---
New, TLSv1/SSLv3, Cipher is ECDHE-RSA-AES128-GCM-SHA256
Server public key is 4096 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
SSL-Session:
    Protocol  : TLSv1.2
    Cipher    : ECDHE-RSA-AES128-GCM-SHA256
    Session-ID: 820EF7CA565E40E495662B0D1AAAB24E2AE431B660A86DF7659D2DEFB7B986B1
    Session-ID-ctx:
    Master-Key: 98F3D990B13A2847041E6275682C74F3D371A15C8D0358434957D6B87B865DA9E839AB95950FE6F24E9D5CDD0DE59F93
    TLS session ticket lifetime hint: 7200 (seconds)
    TLS session ticket:
...
    Start Time: 1580667077
    Timeout   : 7200 (sec)
    Verify return code: 0 (ok)
---
closed
The most important information client should notice are the following:
  • CN = *.gmcr.com -- This dictate how client should invoke the service
  • SHA2 High Assurance Server CA -- SHA2 is Secure Hashing Algorithm 2.
  • Protocol : TLSv1.2 -- We are using TLSv1.2, now Anypoint RTF also support TLSv1.3
  • Cipher : ECDHE-RSA-AES128-GCM-SHA256
  • Verify return code: 0 (ok) -- This is very important.
The last line tells us the TLS certificate is valid and can be verified. If the self-signed certificate is applied, the last line will be something like:
Verify return code: 18 (self signed certificate)

Verify Server's Cipher Suites

It is not very uncommon that server and client could not find the common supported ciphers. To handle this, we need to scan server's cipher suite. I use two tools: nmap and cipherscan. There are many free software available, but I find they are very easy to use and very powerful. Wireshark is another very popular tool. If all of the simple tools are exhausted, we can use Wireshark. Here is example using cipherscan:
$ ./cipherscan 10.64.6.65
Warning: target is not a FQDN. SNI was disabled. Use a FQDN or '-servername '
...............
Target: 10.64.6.65:443

prio  ciphersuite                  protocols  pfs                 curves
1     ECDHE-RSA-AES128-GCM-SHA256  TLSv1.2    ECDH,P-256,256bits  prime256v1,secp384r1,secp521r1
2     ECDHE-RSA-AES256-GCM-SHA384  TLSv1.2    ECDH,P-256,256bits  prime256v1,secp384r1,secp521r1
3     AES256-GCM-SHA384            TLSv1.2    None                None
4     DHE-RSA-AES128-GCM-SHA256    TLSv1.2    DH,2048bits         None
5     AES128-GCM-SHA256            TLSv1.2    None                None

Certificate: trusted, 4096 bits, sha256WithRSAEncryption signature
TLS ticket lifetime hint: 7200
NPN protocols: None
OCSP stapling: not supported
Cipher ordering: server
Curves ordering: server - fallback: no
Server supports secure renegotiation
Server supported compression methods: NONE
TLS Tolerance: yes

Intolerance to:
 SSL 3.254           : absent
 TLS 1.0             : PRESENT
 TLS 1.1             : PRESENT
 TLS 1.2             : absent
 TLS 1.3             : absent
 TLS 1.4             : absent
As you can see, it provide supported cipher and TLS protocols. You can down cipherscan from github: https://github.com/mozilla/cipherscan. nmap is another very powerful and easy to use tool. nmap is a bit slow.
$ nmap -sV --script ssl-enum-ciphers -p 443 10.64.6.65
Starting Nmap 7.80 ( https://nmap.org ) at 2020-02-02 13:11 CST
Nmap scan report for hello-earth.kdrp.com (10.64.6.65)
Host is up (0.086s latency).

PORT    STATE SERVICE   VERSION
443/tcp open  ssl/https
| fingerprint-strings:
|   FourOhFourRequest, GetRequest, HTTPOptions:
|     HTTP/1.1 404 NOT FOUND
|     Content-Length: 0
|     Connection: Close
|   RTSPRequest, SIPOptions:
|     HTTP/1.1 400 BAD REQUEST - bad version
|     Content-Length: 0
|_    Connection: Close
| ssl-enum-ciphers:
|   TLSv1.2:
|     ciphers:
|       TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (ecdh_x25519) - A
|       TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (ecdh_x25519) - A
|       TLS_RSA_WITH_AES_256_GCM_SHA384 (rsa 4096) - A
|       TLS_DHE_RSA_WITH_AES_128_GCM_SHA256 (dh 2048) - A
|       TLS_RSA_WITH_AES_128_GCM_SHA256 (rsa 4096) - A
|     compressors:
|       NULL
|     cipher preference: server
|     warnings:
|       Key exchange (dh 2048) of lower strength than certificate key
|       Key exchange (ecdh_x25519) of lower strength than certificate key
|_  least strength: A
1 service unrecognized despite returning data. If you know the service/version, please submit the following fingerprint at https://nmap.org/cgi-bin/submit.cgi?new-service :
SF-Port443-TCP:V=7.80%T=SSL%I=7%D=2/2%Time=5E371EE9%P=x86_64-apple-darwin1
SF:7.7.0%r(GetRequest,40,"HTTP/1\.1\x20404\x20NOT\x20FOUND\r\nContent-Leng
SF:th:\x200\r\nConnection:\x20Close\r\n\r\n")%r(HTTPOptions,40,"HTTP/1\.1\
SF:x20404\x20NOT\x20FOUND\r\nContent-Length:\x200\r\nConnection:\x20Close\
SF:r\n\r\n")%r(FourOhFourRequest,40,"HTTP/1\.1\x20404\x20NOT\x20FOUND\r\nC
SF:ontent-Length:\x200\r\nConnection:\x20Close\r\n\r\n")%r(RTSPRequest,50,
SF:"HTTP/1\.1\x20400\x20BAD\x20REQUEST\x20-\x20bad\x20version\r\nContent-L
SF:ength:\x200\r\nConnection:\x20Close\r\n\r\n")%r(SIPOptions,50,"HTTP/1\.
SF:1\x20400\x20BAD\x20REQUEST\x20-\x20bad\x20version\r\nContent-Length:\x2
SF:00\r\nConnection:\x20Close\r\n\r\n");

Service detection performed. Please report any incorrect results at https://nmap.org/submit/ .
Nmap done: 1 IP address (1 host up) scanned in 46.51 seconds

Verify REST API

From network point view, everything seems working, but client may still have problem to invoke the REST API exposed on the Anypoint RTF. In these cases, we need to check the following. Using postman, if the certificate applied to Anypoint RTF is self-signed, we need to make sure to turn off the ssl verification on the postman.
Still some client are using plain java to invoke REST API. In this case, we can use the following code:
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class HttpsHelloWorld {

 public static void main(String[] args) {
  // TODO Auto-generated method stub
  System.out.println("Hello, World");
  HttpGet request = new HttpGet("https://kknxplvmsftct.gmcr.com/earth/hello");
  request.addHeader("Host", "hello-earth-one.gmcr.com");
  CloseableHttpClient httpClient = HttpClients.createDefault();
  
        try {
          CloseableHttpResponse response = httpClient.execute(request);
            // Get HttpResponse Status
            System.out.println(response.getStatusLine().toString());

            HttpEntity entity = response.getEntity();
            Header headers = entity.getContentType();
            System.out.println(headers);

            if (entity != null) {
                // return it as a String
                String result = EntityUtils.toString(entity);
                System.out.println(result);
            }
        } catch (Exception e) {
          e.printStackTrace();
        }
     
 }

}
add the following dependencies to pom.xml
  
    org.apache.httpcomponents
    httpclient
    4.5.10
  
  
  
      org.springframework
      spring-core
      5.2.3.RELEASE
  
  
  
      org.springframework
      spring-web
      5.2.3.RELEASE
  

Or if you prefer to use REST template, you can use the following example:

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URI;
import java.net.URL;

import javax.net.ssl.HttpsURLConnection;

import org.apache.http.conn.ssl.NoopHostnameVerifier;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.RequestEntity;
import org.springframework.http.ResponseEntity;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.web.client.HttpClientErrorException;
import org.springframework.web.client.RestTemplate;

public class HttpsPostMes {

 public static void main(String[] args) {
  try {
   httpsRequestCall3();
   
  } catch(Exception e) {
   e.printStackTrace();
   
  }
     
 }

 public static void httpsRequestCall3() {
  
     CloseableHttpClient httpClient
       = HttpClients.custom()
         .setSSLHostnameVerifier(new NoopHostnameVerifier())
         .build();
     
     HttpComponentsClientHttpRequestFactory requestFactory  = new HttpComponentsClientHttpRequestFactory();
     
     requestFactory.setHttpClient(httpClient);
     
     String urlOverHttps = "https://kknxplvmsftct.gmcr.com/earth/hello";
     
     HttpHeaders headers = new HttpHeaders();
     headers.add("Host", "hello-earth-one.gmcr.com");
      HttpEntity entity = new HttpEntity<>("header", headers);
     
  
     ResponseEntity response = new RestTemplate(requestFactory).exchange(urlOverHttps, HttpMethod.GET, entity, String.class);
     org.springframework.http.HttpStatus code = response.getStatusCode();
     
     System.out.println(code);
     
     System.out.print(response);
  
 } 
  

}

Take Aways

In this article, I have covered the following:
  1. Basic Anypoint runtime fabric's controllers
  2. Tools to verify servers ports, SSL protocols, and ciphers
    • nc
    • openssl
    • nmap
    • ciphjerscan
  3. java code to invoke REST API using https

Saturday, October 26, 2019

Mule Integration - Write Elegant Code

Introduction

Recently, I encountered the following piece of Mule Dataweave 2.0 function code.

fun getEmployeePovince(worker) = getStateAbbrevation(worker) match {
     case "AB" -> "AB"
     case "BC" -> "BC"
     case "MB" -> "MB"
     case "NB" -> "NB"
     case "NL" -> "NL"
     case "NS" -> "NS"
     case "NT" -> "NT"
     case "NU" -> "NU"
     case "ON" -> "ON"
     case "PE" -> "PE"
     case "QC" -> "QC"
     case "SK" -> "SK"
     case "YT" -> "YT"
     else -> "ZZ"
    }

The purpose of the above function is to get home province's code of a Canadian employee. The Canadian province code is like, BC for British Columbia, ON for Ontario, etc. The input is an xml object which contains information about the employee. If the worker's province code is not among the list, default to "ZZ".

The above code works and about to go to production. However, this kind of code is really not very cool to say the least. It is just an amateur's code!

Improvement One

First of all, the gist of this kind of problem is to find a match from a given list of Strings. Mule Dataweave 2.0 provides a function, namely find. The documentation can be found here.. The find function works like the following:
['aa', 'bb', 'cc'] find 'xy'  //return [], empty array
['aa', 'bb', 'cc', 'aa'] find 'aa' //return [0, 3]
Now the code using find function should be clear. If the return array from the find is empty (isEmpty(findFunction)), use the input, otherwise, use default, "ZZ".

The following is the datawave code:

%dw 2.0
var CanadianProvinces = ["BC", "MB", "NB", "NL", "NS", "NT", "NU", "NT", "NU", "ON", "PE", "QC", "SK", "YT"]
var pv = payload.state
fun findAKey(aKey) = CanadianProvinces find aKey

output application/json
---
{
 province: if(isEmpty(findAKey(pv))) "ZZ" else pv,
}
The above code is much cleaner. We put the constants of the province code into an array, and use find function. However the above code is still not good for maintenance. Let's see if I want to use the same to logic to US state's code. We have to modify the dataweave code. We can further improve the code. That is to put the constant into property file.

Improvement Two

First, we put the two constants to the yaml property file as the following:
provinces: ["BC", "MB", "NB", "NL", "NS", "NT", "NU", "NT", "NU", "ON", "PE", "QC", "SK", "YT"]
constants:
   default: "ZZ"

%dw 2.0
var provinces = p('provinces')
var pv = payload.state
var dp = p('constants.default')
fun findAKey(aKey) = provinces find aKey

output application/json
---
{
 provice: if(isEmpty(findAKey(pv))) dp else pv,
}

Take Aways

  1. Two dataweave 2.0 functions: switch and find
  2. Array constants in yaml property file
  3. When we encounter some strange code, we should think about the improvement. There is always ways to write elegant code.

Tuesday, September 3, 2019

Install JSON Plugin In Anypoint Studio

Introduction

JSON Plugin is very useful tool for editing and verifying JSON schemas or json examples data in our API deployment. Unfortunately, it does not come with Anypoint Studio. To me, AnypointStudio should more or less behave like Eclipse which allow us to drag and paste any available plugin. This short article describe the procedure to install the plugin.

Installation of JSON Plugin

First download the plugin zip file from this website to ~/Download. The file name should be like:

rw-r--r--@   1 gl17  staff   112K Sep  3 14:38 jsonedit-repository-0.9.7.zip

Second, in AnypointStudio, Help --> Install New Software --> Add

Note, select Achive and from local file.

After installation, restart the AnypointStudion. Now if you open any json file, the Studio will validate the file.

Saturday, August 24, 2019

Manage Mule Runtime Using Linux Services On RHEL 7

Introduction

This article describes the procedures to enable Mule runtime as systemd service for Mule standalone runtime clustering on-premises or in private clouds. Since RHEL 7, the systemd init system is a must. The traditional init.d approach is obsolete. For details about the systemd and Unit files, you may refer to this article.

Assumptions

  • Mule standalone runtime is installed at /opt/mule/runtime/current
  • Mule runtime can be started and stoped by the command /opt/mule/runtime/current/bin/mule start | stop
  • mule user has sudo permission

Create Unit File

First, we need to create a file, mule.service at /etc/systemd/system, with the following contents:
# file: /etc/systemd/system/mule.service
# Systemd unit file for mule standalone runtime
[Unit]
Description=Mule Runtime Standalone Runtime
After=syslog.target network.target

[Service]
Type=forking
WorkingDirectory=/opt/mule/runtime/current
Environment=JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.222.b10-0.el7_6.x86_64
Environment=MULE_HOME=/opt/mule/runtime/current
TasksMax=infinity
LimitNOFILE=65335

ExecStart=/opt/mule/runtime/current/bin/mule start
ExecStop=/opt/mule/runtime/current/bin/mule stop

User=mule
Group=mule

RestartSec=10
Restart=always

[Install]
WantedBy=multi-user.target

$ cd /etc/systemd/system/
$ sudo chmod 644 mule.service
$ sudo systemctl daemon-reload
$ sudo systemctl enable mule.service
The above command will enable the mule.service. This procedure simply creates a line in the folder of: /etc/systemd/system/system-update.target.wants
systemd-readahead-drop.service -> /usr/lib/systemd/system/systemd-readahead-drop.service
Now, we are ready to start the mule runtime as a service. To do this, we must first stop the running Mule runtime:
$ cd /opt/mule/runtime/current
$ bin/mule stop
Now, run the following command:
$ sudo systemctl start mule.service
It may take sometime before we get the prompt back. After that we can check whether the mule runtime is running or not by the following command:
$ sudo systemctl status mule.service
● mule.service - Mule Runtime Standalone Runtime
   Loaded: loaded (/etc/systemd/system/mule.service; enabled; vendor preset: disabled)
   Active: active (running) since Sat 2019-08-24 15:46:04 CDT; 2h 45min ago
 Main PID: 17555 (wrapper-linux-x)
   CGroup: /system.slice/mule.service
           ├─17555 /opt/mule/runtime/current/lib/boot/exec/wrapper-linux-x86-64 /opt/mule/runtime/current/conf/wrapper.conf wrapper.s...
           └─17569 /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.222.b10-0.el7_6.x86_64/jre/bin/java -Dmule.home=/opt/mule/runtime/current -D...

Aug 24 15:45:41 wp37mulerte01.aci.awscloud systemd[1]: Starting Mule Runtime Standalone Runtime...
Aug 24 15:45:41 wp37mulerte01.aci.awscloud mule[17439]: MULE_HOME is set to /opt/mule/runtime/current
Aug 24 15:45:41 wp37mulerte01.aci.awscloud mule[17439]: MULE_BASE is set to /opt/mule/runtime/current
Aug 24 15:45:42 wp37mulerte01.aci.awscloud mule[17439]: Starting Mule Enterprise Edition...
Aug 24 15:46:04 wp37mulerte01.aci.awscloud mule[17439]: Waiting for Mule Enterprise Edition.......................
Aug 24 15:46:04 wp37mulerte01.aci.awscloud mule[17439]: running: PID:17555
Aug 24 15:46:04 wp37mulerte01.aci.awscloud systemd[1]: Started Mule Runtime Standalone Runtime.
As you can see, the mule runtime is running. If you want to know the deatils about the mule runtime, you can use the following command:
$ sudo systemctl -l status mule.service
The -l option will print out the arguments passed to the JVM. To view the history of stop/start of the Mule runtime, we can use the following command:
$ sudo journalctl -u mule.service
-- Logs begin at Tue 2019-08-06 23:11:10 CDT, end at Sat 2019-08-24 18:39:13 CDT. --
Aug 22 21:40:03 wd35mulerte01.aci.awscloud systemd[1]: Starting Mule Runtime Standalone Runtime...
Aug 22 21:40:03 wd35mulerte01.aci.awscloud mule[31293]: MULE_HOME is set to /opt/mule/runtime/current
Aug 22 21:40:03 wd35mulerte01.aci.awscloud mule[31293]: MULE_BASE is set to /opt/mule/runtime/current
Aug 22 21:40:05 wd35mulerte01.aci.awscloud systemd[1]: mule.service: control process exited, code=exited status=1
Aug 22 21:40:05 wd35mulerte01.aci.awscloud systemd[1]: Failed to start Mule Runtime Standalone Runtime.
Aug 22 21:40:05 wd35mulerte01.aci.awscloud systemd[1]: Unit mule.service entered failed state.
Aug 22 21:40:05 wd35mulerte01.aci.awscloud systemd[1]: mule.service failed.
Aug 22 21:40:14 wd35mulerte01.aci.awscloud systemd[1]: Stopped Mule Runtime Standalone Runtime.
Aug 22 21:52:39 wd35mulerte01.aci.awscloud systemd[1]: Starting Mule Runtime Standalone Runtime...
Aug 22 21:52:39 wd35mulerte01.aci.awscloud mule[32610]: MULE_HOME is set to /opt/mule/runtime/current
Aug 22 21:52:39 wd35mulerte01.aci.awscloud mule[32610]: MULE_BASE is set to /opt/mule/runtime/current
Aug 22 21:52:40 wd35mulerte01.aci.awscloud mule[32610]: Starting Mule Enterprise Edition...
Aug 22 21:53:03 wd35mulerte01.aci.awscloud mule[32610]: Waiting for Mule Enterprise Edition.........................
Aug 22 21:53:04 wd35mulerte01.aci.awscloud mule[32610]: running: PID:32750
Aug 22 21:53:04 wd35mulerte01.aci.awscloud systemd[1]: Started Mule Runtime Standalone Runtime.
Aug 22 21:54:15 wd35mulerte01.aci.awscloud systemd[1]: Stopping Mule Runtime Standalone Runtime...
Aug 22 21:54:15 wd35mulerte01.aci.awscloud mule[633]: MULE_HOME is set to /opt/mule/runtime/current
Aug 22 21:54:15 wd35mulerte01.aci.awscloud mule[633]: MULE_BASE is set to /opt/mule/runtime/current
Aug 22 21:54:15 wd35mulerte01.aci.awscloud mule[633]: Stopping Mule Enterprise Edition...
Aug 22 21:54:18 wd35mulerte01.aci.awscloud systemd[1]: Stopped Mule Runtime Standalone Runtime.
Aug 22 21:55:43 wd35mulerte01.aci.awscloud systemd[1]: Starting Mule Runtime Standalone Runtime...
Aug 22 21:55:44 wd35mulerte01.aci.awscloud mule[912]: MULE_HOME is set to /opt/mule/runtime/current
Aug 22 21:55:44 wd35mulerte01.aci.awscloud mule[912]: MULE_BASE is set to /opt/mule/runtime/current
Aug 22 21:55:45 wd35mulerte01.aci.awscloud mule[912]: Starting Mule Enterprise Edition...
Aug 22 21:56:08 wd35mulerte01.aci.awscloud mule[912]: Waiting for Mule Enterprise Edition.........................
Aug 22 21:56:08 wd35mulerte01.aci.awscloud mule[912]: running: PID:1091
Aug 22 21:56:08 wd35mulerte01.aci.awscloud systemd[1]: Started Mule Runtime Standalone Runtime.

That is it. It is very helpful to study the commands of systemctl and journalctl.

Sunday, August 18, 2019

Two-Way SSL In Mule Application - Part 2

Introduction

In my previous article in DZone or here, I omitted the procedure to create a trust store for the application. This is important if the applications are deployed to the CloudHub.

In this article, I will describe the procedures to create the trust store and how to configure the HTTPS request for Mule application

Create A Trust Store FOR MULE HTTPS Request

The procedures to import the server's PEM certificate to a trust store are the following.

First, we will create a trust store using the following command:

keytool -genkey -keyalg RSA -alias cyberark-poc -keystore truststore.ks
Enter anything. They are not important as we will delete it.

Second, delete the content of the trust store just created:

keytool -delete -alias cyberark-poc -keystore truststore.ks
Third, import the server's certificate:
keytool -import -v -trustcacerts -alias cyberark-server -file SERVER-CERT.pem -keystore truststore.ks
Now, copy the truststore.ks to Mule application project /src/main/resources

HTTPS Request Configuration

The following is the complete HTTPS Request configuration:
 
  
   
    
    
   
  
 
Note: I put both client.pfx and truststore in the directory of /src/main/resources. You may put them into different directory. In that case, you need to give the full path relative to the Mule Application Project, such as ssh/cert/client.pfx.

The Key Takeaways

The best practice for certificates manipulation is:
  1. If the deployment is on-prem, import servers' certificates to cacert. In this way if the server's certificate is expired, we just need to reimport, not code change is required.
  2. If the deployment is CloudHub, we have to import the servers' certificate to a truststore as described in this article.
  3. Use JKS format for the trust store used in the HTTPS request. It is most popular one.

Sunday, August 11, 2019

Two-Way SSL In Mule Application

Introduction

In my previous article, I have explained how Two-Way SSL works with the context of Mule Application. Many people have asked the question about how to setup HTTPS request in Mule application. This article provide the details about the procedures to invoke HTTPS services which require Two-Way SSL or Mutual Authentication. Before we dive into the detail procedures, lets review how Two-Way SLL works between clients and servers.

The gist of Two-Way SSL is to exchange certificates between clients and servers. The details are pretty complicated and they beyond the scope of this article. Basically, here are the high level scheme of the exchange of certificates:
  1. Client send a ClientHello message to a server
  2. Server replies with ServerHello, Server's certificate, and Request for Client's certificate
  3. Client its certificate other information like cipher scheme, server's certificate verification, etc.
  4. Server replies with cipher scheme.
  5. Start to exchange information
Now, how do we setup Mule Application as client?

Client's Certificate Generation

In general, IT admin will generate client certificates similar as I describe in my blog here Let's assume that is the way for now so that we can describe how to setup Mule HTTPS Request. Before we continue, we need to obtain server's certificate in advance. The certificate can be in many forms like JKS, PKCS12, PEM, etc. Mule HTTPS request support three forms:
  • JKS
  • PKCS12
  • JCEKS
Let's say if we got PEM format from the server. We need to do one of the two things depending on the deployment pattern.
  • if it is on-prem deployment, the best way is to import the cert to JVM cacerts
  • if it is deployed to MuleSoft CloudHub, we need to convert the PEM to PKCS12.
If it is on-prem deplopment, we can import the the PEM certificate directly into cacerts here is the procedure (Make sure you have sudo permission, and server's cert is named like SERVER_CERT.pem)
cd ${JAVA_HOME}/jre/lib/security
cp SERVER_CERT.pem
sudo keytool -import -alias mule1-cyberark -keystore cacerts -file SERVER_CERT.pem
To be sure that server's cert is in pem format, you can use the following command:
$ openssl x509 -in SERVER_CERT.pem -text
If it is CloudHub deployment, we need to convert the pem file to PKCS12 format. Here is the command:
$ openssl pkcs12 -export -nokeys -in SERVER_CERT.pem -out SERVER_CERT.pfx

Note the option of "-nokeys". This means I do not have the private key of the certificate. Now we have server's certificates being taken care of. We need to convert the client's certificate to PKCS12. Here is the command to do so:

 openssl pkcs12 -export -in cacert.pem -inkey cakey.pem -out identity.p12 -name "mykey"

Note the above procedure will ask the password. Make sure you remember it.

Setup Mule Flow

The following diagram shows the simple Mule flow
The https request configuration is the following:

 
  
   
    
   
  
 
 
The import point here is that client's certificate is

and server's certificates is

Friday, August 9, 2019

How To Pass MuleSoft Certified Developer - Level 1 (Mule 4)

Congratulation Gary!

First of all, I must congratulate myself for getting this done. For almost a year, I have been thinking to take the exam, but my project schedules have been crazy. I hardly find time to prepare the certification. Three weeks ago, I decided to give a shot. I studied two weekends, and spend about 1 hour each day. And today, I did! I must say that I feel it is a kind of accomplishment. This test is not easy!
Here I will try to summarized my feeling about the test and how I prepared the test. Hopefully, it will provided some help to those who are thinking to take the test.

The Procedures

First of all, go to Mule training website and paid 250 USD online and schedule a test at the same time. I did my test at my local test center. There, I have to lock away my cell phone, watch, wallet, even my hat! It is very quiet and comfortable place. Not many people there either.

The exam is 2 hours long. That is plenty time to ponder each question carefully. At the first 10 minutes, MuleSoft did a survey about my experience in Mule, how I prepared the test, what role I play, etc. I am not sure why they should ask these questions at all. One thing really makes me suspicious is that if you are a very experience developer, you may get harder questions. It is just my guess!

How Was My Test Results?

It took me 88 minutes to submit the answer. I know I had plenty time, so that I read each question very carefully and did not plan to review them once I am done with all the questions.

The following are the results I got:

Creating Application Networks: 100.00%

Designing APIs: 100.00%

Building API Implementation Interfaces: 100.00%

Deploying and Managing APIs and Integrations: 75.00%

Accessing and Modifying Mule Events: 83.33%

Structuring Mule Applications: 66.66%

Routing Events: 80.00%

Handling Errors: 80.00%

Troubleshooting and Testing Mule Applications: 66.66%

Writing DataWeave Transformations: 100.00%

Using Connectors: 83.33%

Processing Records: 100.00%

Result: PASS
Roughly, my overall score is about 89%. I think I did pretty OK given that I did not have enough time to prepare. I have no idea why my trouble shooting score is only 66.66%. I thought this is my strongest area.

How Do I Feel About The Questions?

Overall, I think the questions are very good, but many of them are very hard to answer with confidence. About 15% of the questions are really hard.

The challenges come from several fronts. Firstly, most of the questions are very long. You must read the question at least two times before you answer the question. This really tests your English as the questions are very tricky. Secondly, most questions are really difficult to 100% sure from the first glance. You have to read them very carefully. Sometimes the brackets, comma, and semicolon make the difference. Thirdly, some questions are rare to encounter in real life, such as exporting artifacts from Anypoint Studio. We normally don't do this. All in all, I think MuleSoft training department did a good job. It seems the Mule 4 MCD is a bit harder the Mule 3 one.

How I Prepared My Test

I really don't have the time to go through all the training materials. Definitely no time to go through all the DIY.

Here is the procedure I took. I think if you are experience developer and want to pass the test at the first shot. You can follow my way.

  1. Go to the final Quiz at the last Module of the training material, and try to answer them. They are pretty difficult actually. Many of them, I really had trouble to answer at the first time. The good news is that for each question, if you did not answer correctly, the website tell you the right answer. Thus you can figure out why.
  2. Quickly go through each chapter and all the slides. Notes down what the chapter is about.
  3. After the first two steps, I start to create many mini-code to really understand the details about connectors, error handling, different scopes, etc.
  4. Take notes. Take a lot of notes. These notes really help me to remember the nitty-mitty details. Remember, to pass the test, you must pay attention to tiny details.

Some Thoughts About The Certification

Definitely, it worths the time and energy to prepare and take the Exam. It really lets us to start paying attention to details and try to think about the reason about the way MuleSoft implements connectors, design patterns, and other systems. It is not for beginner anyway.

Don't take the delta test. To me, it is really better to challenge ourselves and take Mule 4 MCD.

The questions have a lot of room to improve.

  • It should really focus on how our daily development works.
  • Questions should more focus on development of Mule flows, less memorization of syntaxes.
  • More questions on design and troubleshooting.
  • More questions on problem solving skills.

Anypoint Studio Error: The project is missing Munit lIbrary to run tests

Anypoint Studio 7.9 has a bug. Even if we following the article: https://help.mulesoft.com/s/article/The-project-is-missing-MUnit-libraries-...