Testing SSL certificate validity – client and server

When accessing a web application via the https protocol, a secure channel is established between the client (usually the browser) and the server. The identity of one (the server) or both parties (client and server) is then established by means of digital certificates. In order for the communication to be set up, a number of checks on the certificates must be passed. a) checking if the Certificate Authority (CA) is a known one (meaning one considered trusted), b) checking that the certificate is currently valid, and c) checking that the name of the site and the name reported in the certificate match. Remember to upgrade your browser because CA certs expired too, in every release of the browser, CA Certs has been renewed. Moreover it's important to update the browser because more web sites require strong cipher more of 40 or 56 bit.
Let’s examine each check more in detail.
a) Each browser comes with a preloaded list of trusted CAs, against which the certificate signing CA is compared (this list can be customized and expanded at will). During the initial negotiations with an https server, if the server certificate relates to a CA unknown to the browser, a warning is usually raised. This happens most often because a web application relies on a certificate signed by a self-established CA. Whether this is to be considered a concern depends on several factors. For example, this may be fine for an Intranet environment (think of corporate web email being provided via https; here, obviously all users recognize the internal CA as a trusted CA). When a service is provided to the general public via the Internet, however (i.e. when it is important to positively verify the identity of the server we are talking to), it is usually imperative to rely on a trusted CA, one which is recognized by all the user base (and here we stop with our considerations; we won’t delve deeper in the implications of the trust model being used by digital certificates).
b) Certificates have an associated period of validity, therefore they may expire. Again, we are warned by the browser about this. A public service needs a temporally valid certificate; otherwise, it means we are talking with a server whose certificate was issued by someone we trust, but has expired without being renewed.
c) What if the name on the certificate and the name of the server do not match? If this happens, it might sound suspicious. For a number of reasons, this is not so rare to see. A system may host a number of name-based virtual hosts, which share the same IP address and are identified by means of the HTTP 1.1 Host: header information. In this case, since the SSL handshake checks the server certificate before the HTTP request is processed, it is not possible to assign different certificates to each virtual server. Therefore, if the name of the site and the name reported in the certificate do not match, we have a condition which is typically signalled by the browser. To avoid this, one of two techniques should be used. First is Server Name Indication (SNI), which is a TLS extension from RFC 3546; and second is IP-based virtual servers must be used. [2] and [3] describe techniques to deal with this problem and allow name-based virtual hosts to be correctly referenced.

DER vs. CRT vs. CER vs. PEM Certificates and How To Convert Them

Certificates and Encodings

At its core an X.509 certificate is a digital document that has been encoded and/or digitally signed according to RFC 5280.
In fact, the term X.509 certificate usually refers to the IETF’s PKIX Certificate and CRL Profile of the X.509 v3 certificate standard, as specified in RFC 5280, commonly referred to as PKIX for Public Key Infrastructure (X.509).

X509 File Extensions

The first thing we have to understand is what each type of file extension is.   There is a lot of confusion about what DER, PEM, CRT, and CER are and many have incorrectly said that they are all interchangeable.  While in certain cases some can be interchanged the best practice is to identify how your certificate is encoded and then label it correctly.  Correctly labeled certificates will be much easier to manipulat

Encodings (also used as extensions)

• .DER = The DER extension is used for binary DER encoded certificates. These files may also bear the CER or the CRT extension.   Proper English usage would be “I have a DER encoded certificate” not “I have a DER certificate”.
• .PEM = The PEM extension is used for different types of X.509v3 files which contain ASCII (Base64) armored data prefixed with a “—– BEGIN …” line.

Common Extensions

• .CRT = The CRT extension is used for certificates. The certificates may be encoded as binary DER or as ASCII PEM. The CER and CRT extensions are nearly synonymous.  Most common among *nix systems
• CER = alternate form of .crt (Microsoft Convention) You can use MS to convert .crt to .cer (.both DER encoded .cer, or base64[PEM] encoded .cer)  The .cer file extension is also recognized by IE as a command to run a MS cryptoAPI command (specifically rundll32.exe cryptext.dll,CryptExtOpenCER) which displays a dialogue for importing and/or viewing certificate contents.
• .KEY = The KEY extension is used both for public and private PKCS#8 keys. The keys may be encoded as binary DER or as ASCII PEM.

The only time CRT and CER can safely be interchanged is when the encoding type can be identical.  (ie  PEM encoded CRT = PEM encoded CER)

Common OpenSSL Certificate Manipulations

There are four basic types of certificate manipulations. View, Transform, Combination , and Extraction

View

Even though PEM encoded certificates are ASCII they are not human readable.  Here are some commands that will let you output the contents of a certificate in human readable form;

View PEM encoded certificate

Use the command that has the extension of your certificate replacing cert.xxx with the name of your certificate

openssl x509 -in cert.pem -text -noout
openssl x509 -in cert.cer -text -noout
openssl x509 -in cert.crt -text -noout

If you get the folowing error it means that you are trying to view a DER encoded certifciate and need to use the commands in the “View DER encoded certificate  below”

unable to load certificate
12626:error:0906D06C:PEM routines:PEM_read_bio:no start line:pem_lib.c:647:Expecting: TRUSTED CERTIFICATE

View DER encoded Certificate

openssl x509 -in certificate.der -inform der -text -noout

If you get the following error it means that you are trying to view a PEM encoded certificate with a command meant for DER encoded certs. Use a command in the “View PEM encoded certificate above

unable to load certificate
13978:error:0D0680A8:asn1 encoding routines:ASN1_CHECK_TLEN:wrong tag:tasn_dec.c:1306:
13978:error:0D07803A:asn1 encoding routines:ASN1_ITEM_EX_D2I:nested asn1 error:tasn_dec.c:380:Type=X509

Transform

Transforms can take one type of encoded certificate to another. (ie. PEM To DER conversion)

PEM to DER

openssl x509 -in cert.crt -outform der -out cert.der

DER to PEM

openssl x509 -in cert.crt -inform der -outform pem -out cert.pem

Combination

In some cases it is advantageous to combine multiple pieces of the X.509 infrastructure into a single file.  One common example would be to combine both the private key and public key into the same certificate.
The easiest way to combine certs keys and chains is to convert each to a PEM encoded certificate then simple copy the contents of each file into a new file.   This is suitable for combining files to use in applications lie Apache.

Extraction

Some certs will come in a combined form.  Where one file can contain any one of: Certificate, Private Key, Public Key, Signed Certificate, Certificate Authority (CA), and/or Authority Chain.

Ref: https://support.ssl.com/Knowledgebase/Article/View/19/0/der-vs-crt-vs-cer-vs-pem-certificates-and-how-to-convert-them

How to create a self-signed SSL Certificate

Overview

The following is an extremely simplified view of how SSL is implemented and what part the certificate plays in the entire process.
Normal web traffic is sent unencrypted over the Internet. That is, anyone with access to the right tools can snoop all of that traffic. Obviously, this can lead to problems, especially where security and privacy is necessary, such as in credit card data and bank transactions. The Secure Socket Layer is used to encrypt the data stream between the web server and the web client (the browser).
SSL makes use of what is known as asymmetric cryptography, commonly referred to as public key cryptography (PKI). With public key cryptography, two keys are created, one public, one private. Anything encrypted with either key can only be decrypted with its corresponding key. Thus if a message or data stream were encrypted with the server's private key, it can be decrypted only using its corresponding public key, ensuring that the data only could have come from the server.
If SSL utilizes public key cryptography to encrypt the data stream traveling over the Internet, why is a certificate necessary? The technical answer to that question is that a certificate is not really necessary - the data is secure and cannot easily be decrypted by a third party. However, certificates do serve a crucial role in the communication process. The certificate, signed by a trusted Certificate Authority (CA), ensures that the certificate holder is really who he claims to be. Without a trusted signed certificate, your data may be encrypted, however, the party you are communicating with may not be whom you think. Without certificates, impersonation attacks would be much more common.

Step 1: Generate a Private Key

The openssl toolkit is used to generate an RSA Private Key and CSR (Certificate Signing Request). It can also be used to generate self-signed certificates which can be used for testing purposes or internal usage.

The first step is to create your RSA Private Key. This key is a 1024 bit RSA key which is encrypted using Triple-DES and stored in a PEM format so that it is readable as ASCII text.

openssl genrsa -des3 -out server.key 1024

Generating RSA private key, 1024 bit long modulus
.........................................................++++++
........++++++
e is 65537 (0x10001)
Enter PEM pass phrase:
Verifying password - Enter PEM pass phrase:

Step 2: Generate a CSR (Certificate Signing Request)

Once the private key is generated a Certificate Signing Request can be generated. The CSR is then used in one of two ways. Ideally, the CSR will be sent to a Certificate Authority, such as Thawte or Verisign who will verify the identity of the requestor and issue a signed certificate. The second option is to self-sign the CSR, which will be demonstrated in the next section.

During the generation of the CSR, you will be prompted for several pieces of information. These are the X.509 attributes of the certificate. One of the prompts will be for "Common Name (e.g., YOUR name)". It is important that this field be filled in with the fully qualified domain name of the server to be protected by SSL. If the website to be protected will be https://public.akadia.com, then enter public.akadia.com at this prompt. The command to generate the CSR is as follows:

openssl req -new -key server.key -out server.csr

Country Name (2 letter code) [GB]:CH
State or Province Name (full name) [Berkshire]:Bern
Locality Name (eg, city) [Newbury]:Oberdiessbach
Organization Name (eg, company) [My Company Ltd]:Akadia AG
Organizational Unit Name (eg, section) []:Information Technology
Common Name (eg, your name or your server's hostname) []:public.akadia.com
Email Address []:martin dot zahn at akadia dot ch
Please enter the following 'extra' attributes
to be sent with your certificate request
A challenge password []:
An optional company name []:

Step 3: Remove Passphrase from Key

One unfortunate side-effect of the pass-phrased private key is that Apache will ask for the pass-phrase each time the web server is started. Obviously this is not necessarily convenient as someone will not always be around to type in the pass-phrase, such as after a reboot or crash. mod_ssl includes the ability to use an external program in place of the built-in pass-phrase dialog, however, this is not necessarily the most secure option either. It is possible to remove the Triple-DES encryption from the key, thereby no longer needing to type in a pass-phrase. If the private key is no longer encrypted, it is critical that this file only be readable by the root user! If your system is ever compromised and a third party obtains your unencrypted private key, the corresponding certificate will need to be revoked. With that being said, use the following command to remove the pass-phrase from the key:

cp server.key server.key.org
openssl rsa -in server.key.org -out server.key

The newly created server.key file has no more passphrase in it.

-rw-r--r-- 1 root root 745 Jun 29 12:19 server.csr
-rw-r--r-- 1 root root 891 Jun 29 13:22 server.key
-rw-r--r-- 1 root root 963 Jun 29 13:22 server.key.org

Step 4: Generating a Self-Signed Certificate

At this point you will need to generate a self-signed certificate because you either don't plan on having your certificate signed by a CA, or you wish to test your new SSL implementation while the CA is signing your certificate. This temporary certificate will generate an error in the client browser to the effect that the signing certificate authority is unknown and not trusted.
To generate a temporary certificate which is good for 365 days, issue the following command:

openssl x509 -req -days 365 -in server.csr -signkey server.key -out server.crt
Signature ok
subject=/C=CH/ST=Bern/L=Oberdiessbach/O=Akadia AG/OU=Information
Technology/CN=public.akadia.com/Email=martin dot zahn at akadia dot ch
Getting Private key

Step 5: Installing the Private Key and Certificate

When Apache with mod_ssl is installed, it creates several directories in the Apache config directory. The location of this directory will differ depending on how Apache was compiled.

cp server.crt /usr/local/apache/conf/ssl.crt
cp server.key /usr/local/apache/conf/ssl.key

Step 6: Configuring SSL Enabled Virtual Hosts

SSLEngine on
SSLCertificateFile /usr/local/apache/conf/ssl.crt/server.crt
SSLCertificateKeyFile /usr/local/apache/conf/ssl.key/server.key
SetEnvIf User-Agent ".*MSIE.*" nokeepalive ssl-unclean-shutdown
CustomLog logs/ssl_request_log \
   "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"

Step 7: Restart Apache and Test

/etc/init.d/httpd stop
/etc/init.d/httpd start

https://public.akadia.com

Ref:  http://www.akadia.com/services/ssh_test_certificate.html

What is SSLyze?

SSLyze

Fast and full-featured SSL scanner.

Description

SSLyze is a Python tool that can analyze the SSL configuration of a server by
connecting to it. It is designed to be fast and comprehensive, and should help
organizations and testers identify misconfigurations affecting their SSL
servers.

Key features include:
* Multi-processed and multi-threaded scanning (it's fast)
* SSL 2.0/3.0 and TLS 1.0/1.1/1.2 compatibility
* Performance testing: session resumption and TLS tickets support
* Security testing: weak cipher suites, insecure renegotiation, CRIME, Heartbleed and more
* Server certificate validation and revocation checking through OCSP stapling
* Support for StartTLS handshakes on SMTP, XMPP, LDAP, POP, IMAP, RDP and FTP
* Support for client certificates when scanning servers that perform mutual authentication
* XML output to further process the scan results
* And much more !

Installation

SSLyze requires Python 2.7; the supported platforms are Windows 7 32/64 bits,
Linux 32/64 bits and OS X 64 bits.

SSLyze is statically linked with OpenSSL. For this reason, the easiest
way to run SSLyze is to download one the pre-compiled packages available in
the GitHub releases section for this project, at
https://github.com/iSECPartners/sslyze/releases.

Usage

### Command line options

The following command will provide the list of available command line options:
    $ python sslyze.py -h


### Sample command line:

    $ python sslyze.py --regular www.isecpartners.com:443 www.google.com

See the test folder for additional examples.

Build / nassl

SSLyze is all Python code but since version 0.7, it uses a custom OpenSSL
wrapper written in C called nassl. The pre-compiled packages for SSLyze
contain a compiled version of this wrapper in sslyze/nassl. If you want to
clone the SSLyze repo, you will have to get a compiled version of nassl from
one of the SSLyze packages and copy it to sslyze-master/nassl, in order to get
SSLyze to run.

The source code for nassl is hosted at https://github.com/nabla-c0d3/nassl.

Py2exe Build

SSLyze can be packaged as a Windows executable by running the following command:

    $ python.exe setup_py2exe.py py2exe

License

GPLv2 - See LICENSE.txt.




Ref: https://github.com/iSECPartners/sslyze

What Is a Realm?

Realm

For a web application, a realm is a complete database of users and groups that identify valid users of a web application (or a set of web applications) and are controlled by the same authentication policy.

The Java EE server authentication service can govern users in multiple realms. In this release of the Application Server, the file, admin-realm, and certificate realms come preconfigured for the Application Server.

In the file realm, the server stores user credentials locally in a file named keyfile. You can use the Admin Console to manage users in the file realm.

When using the file realm, the server authentication service verifies user identity by checking the file realm. This realm is used for the authentication of all clients except for web browser clients that use the HTTPS protocol and certificates.

In the certificate realm, the server stores user credentials in a certificate database. When using the certificate realm, the server uses certificates with the HTTPS protocol to authenticate web clients. To verify the identity of a user in the certificate realm, the authentication service verifies an X.509 certificate. For step-by-step instructions for creating this type of certificate, see Working with Digital Certificates. The common name field of the X.509 certificate is used as the principal name.

The admin-realm is also a FileRealm and stores administrator user credentials locally in a file named admin-keyfile. You can use the Admin Console to manage users in this realm in the same way you manage users in the file realm. For more information, see Managing Users and Groups on the Application Server.

OpenEdge Supports?

Realm	Description
JDBC Realm	The JDBC realm is a user management system built on a database. It reads user, password, group, and Bussiness Process Server specific information from the database. It also provides password encryption
LDAP	The LDAP realm employs the LDAP directory service to retrieve user, password, and general group information. Other Business Process Server-specific information is retrieved from the database. LDAP runs over TCP/IP and features a hierarchical structure. Business Process Server supports Sun Java System Directory Server 5.2 and MS Active Directory for Windows 2000.
LDAP	The LDAP hybrid realm uses a combination of LDAP realm and Business Process Server database. Typically, the LDAP realm is used for authentication and Business Process Server database is used to store groups related information.
OERealm	The OEHybrid realm is a combination of the JDBC realm and the OpenEdge AppServer based service. Business Process Server (BP Server) supports the single point of authentication (SPA) service using the OEHybrid realm.

KeepAlive

A keepAlive (KA) is a message sent by one device to another to check that the link between the two is operating, or to prevent this link from being broken.

A keepalive signal is often sent at predefined intervals, and plays an important role on the Internet. After a signal is sent, if no reply is received the link is assumed to be down and future data will be routed via another path until the link is up again. A keepalive signal can also be used to indicate to Internet infrastructure that the connection should be preserved. Without a keepalive signal, intermediate NAT-enabled routers can drop the connection after timeout.

Since the only purpose is to find links that don't work or to indicate links that should be preserved, keepalive messages tend to be short and not take much bandwidth. However, their precise format and usage terms depend on the communication protocol.

TCP keepalive

Transmission Control Protocol (TCP) keepalives are an optional feature, and if included must default to off.[1] The keepalive packet contains null data. In an Ethernet network, a keepalive frame length is 60 bytes, while the server response to this, also a null data frame, is 54 bytes.[citation needed] There are three parameters related to keepalive:

    Keepalive time is the duration between two keepalive transmissions in idle condition. TCP keepalive period is required to be configurable and by default is set to no less than 2 hours.
    Keepalive interval is the duration between two successive keepalive retransmissions, if acknowledgement to the previous keepalive transmission is not received.
    Keepalive retry is the number of retransmissions to be carried out before declaring that remote end is not available.

Does OpenEdge AppServer support KeepAlive?

An OpenEdge application that employs the AppServer is vulnerable to failures in the persistent TCP/IP connections that are established between the client and the AppServer.   These connections can fail for the following reasons:

Category of Error	Description
closed connection	The client or server application has purposely closed the connection.
process abort	The client or server application process has aborted, but the TCP/IP stack on the host machine is still functional.
host machine crash	The machine where the client or server application is running has crashed.  The TCP/IP stack on the crashed machine is not functional.
network failure	The network between the client and server application host machines has failed.  The TCP/IP stacks on the host machines are still functional, but no route through the network exists between the two host machines.

In the first two cases (closed connections or process abort), TCP/IP notifies the remaining application[1], allowing it to react appropriately.  In the latter two cases (machine crash or network failure), however, the failures are not immediately detected by TCP/IP, leaving the application unaware that a problem has occurred[2].  When this happens, the application is often stalled, consuming system resources and unable to perform additional work.

The features described in this document attempt to improve the ability of the stalled application to detect these “undetected” network failures and react to them.  The specific use cases addressed by the Distributed Component Awareness (DCA) AppServer Keepalive protocol are described below, followed by a description of the protocol.

---

[1] The notification usually comes in the form of a close event when the application attempts to read data from the connection.

[2] Actually, a subcase of the ‘host machine crash’ scenario exists.  If the host machine crashes and restarts before the TCP/IP keepalive interval expires, then an attempt to send data to that machine will result in an immediate error as the old connection is unknown to restarted TCP/IP stack.  For purposes of simplicity, we will ignore this case.

To address the problems described above, OpenEdge has introduced the AppServer Keepalive (ASK) Protocol.  This protocol actually consists of two features, referred to as the serverASK and clientASK protocols.  The serverASK protocol allows the AppServer to detect failures of the client, while the clientASK protocol allows the client to detect failures of the AppServer.

It should be noted that these two protocols operate independently of one another, and therefore may be deployed as such .

Also Refer:
http://tldp.org/HOWTO/TCP-Keepalive-HOWTO/overview.html

Overview of the JMS API

This overview defines the concept of messaging, describes the JMS API and when it can be used

What Is Messaging?

Messaging is a method of communication between software components or applications. A messaging system is a peer-to-peer facility: A messaging client can send messages to, and receive messages from, any other client. Each client connects to a messaging agent that provides facilities for creating, sending, receiving, and reading messages.

Messaging enables distributed communication that is loosely coupled. A component sends a message to a destination, and the recipient can retrieve the message from the destination. However, the sender and the receiver do not have to be available at the same time in order to communicate. In fact, the sender does not need to know anything about the receiver; nor does the receiver need to know anything about the sender. The sender and the receiver need to know only which message format and which destination to use. In this respect, messaging differs from tightly coupled technologies, such as Remote Method Invocation (RMI), which require an application to know a remote application’s methods.

Messaging also differs from electronic mail (email), which is a method of communication between people or between software applications and people. Messaging is used for communication between software applications or software components.

What Is the JMS API?

The Java Message Service is a Java API that allows applications to create, send, receive, and read messages. Designed by Sun and several partner companies, the JMS API defines a common set of interfaces and associated semantics that allow programs written in the Java programming language to communicate with other messaging implementations.

The JMS API minimizes the set of concepts a programmer must learn in order to use messaging products but provides enough features to support sophisticated messaging applications. It also strives to maximize the portability of JMS applications across JMS providers in the same messaging domain.

The JMS API enables communication that is not only loosely coupled but also:

    Asynchronous: A JMS provider can deliver messages to a client as they arrive; a client does not have to request messages in order to receive them.

    Reliable: The JMS API can ensure that a message is delivered once and only once. Lower levels of reliability are available for applications that can afford to miss messages or to receive duplicate messages.

When Can You Use the JMS API?

An enterprise application provider is likely to choose a messaging API over a tightly coupled API, such as a remote procedure call (RPC), under the following circumstances.

    The provider wants the components not to depend on information about other components’ interfaces, so components can be easily replaced.

    The provider wants the application to run whether or not all components are up and running simultaneously.

    The application business model allows a component to send information to another and to continue to operate without receiving an immediate response.

For example, components of an enterprise application for an automobile manufacturer can use the JMS API in situations like these:

    The inventory component can send a message to the factory component when the inventory level for a product goes below a certain level so the factory can make more cars.

    The factory component can send a message to the parts components so the factory can assemble the parts it needs.

    The parts components in turn can send messages to their own inventory and order components to update their inventories and to order new parts from suppliers.

    Both the factory and the parts components can send messages to the accounting component to update budget numbers.

    The business can publish updated catalog items to its sales force.

Using messaging for these tasks allows the various components to interact with one another efficiently, without tying up network or other resources. Following figure illustrates how this simple example might work.

Manufacturing is only one example of how an enterprise can use the JMS API. Retail applications, financial services applications, health services applications, and many others can make use of messaging.

PAS for OpenEdge / OpenEdge Next Generation AppServer

What is PAS?

1. PAS is an abbreviation for Pacific Application Server
2. Unified Application Server for Progress based applications
• OpenEdge
• Rollbase
• Corticon
3. PAS utilizes Apache Tomcat Server as its web server

What is PAS for OpenEdge?

Is a PAS For deploying, hosting and managing OpenEdge applications Integrated into one layer
Is available in two separate products:
    The Pacific Production Application Server for OpenEdge
    The Pacific Development Application Server for OpenEdge

Why PAS for OE?

1. Simple
• Administration
• Scalability
• Deployment
2. Extensible
• REST APIs for customer developed metrics, monitoring, and administration 
3. Analysis Tools
• Built-in metrics gathering, current state queries
4. Faster and optimized
• Runs same ABL application and client load with less memory and CPU consumption

PAS for OpenEdge Administration

1. tcman.sh
2. OpenEdge Explorer / OpenEdge Management
3. Management REST API
4. JMX remote access

POODLE SSLv3 Vulnerability

POODLE abbreviates to Padding Oracle On Downgraded Legacy Encryption.
This vulnerability was discovered by Bodo Möller, Thai Duong & Krzysztof Kotowicz from the GOOGLE security team.
It has been listed in NVD (National Vulnerability Database)

The most severe problem of CBC encryption in SSL 3.0 is that its block cipher padding is not deterministic, and not covered by the MAC (Message Authentication Code): thus, the integrity of padding cannot be fully verified when decrypting

Some Transport Layer Security (TLS) implementations are also vulnerable to the POODLE attack.

Systems Affected

All systems and applications utilizing the Secure Socket Layer (SSL) 3.0 with cipher-block chaining (CBC) mode ciphers may be vulnerable.