WASD VMS Web Services - Features and Facilities

4 - Transport Layer Security

4.1 - SSL Functionality Sources 4.2 - WASD SSL Quick-Start 4.3 - SSL Configuration 4.3.1 - WASD_CONFIG_SERVICE 4.3.2 - SSL Versions 4.3.3 - SSL Ciphers 4.3.4 - (Open)SSL Options 4.3.5 - Forward Secrecy 4.3.6 - Session Resumption 4.3.7 - Strict Transport Security 4.3.8 - SSL Server Certificate 4.3.9 - SSL Private Key 4.3.10 - SSL Virtual Services 4.3.11 - SSL Access Control 4.3.12 - Authorization Using X.509 Certification 4.3.13 - X.509 Certificate Renegotiation 4.3.14 - Features 4.3.15 - Subject Alternative Name and Other Extensions 4.3.16 - X509 Configuration 4.3.17 - Certificate Authority Verification File 4.3.18 - X.509 Authorization CGI Variables 4.4 - Certificate Management 4.4.1 - Server Certificate 4.4.2 - Client Certificate 4.4.3 - Certificate Signing Request 4.5 - SSL CGI Variables 4.6 - SSL Service Evaluation 4.7 - SSL References
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Transport Layer Security (TLS), and its predecessor Secure Sockets Layer (SSL), are cryptographic protocols designed to provide communication privacy over a network, in the case of HTTP between the browser (client) and the server. It also authenticates server and optionally client identity. TLS/SSL operates by establishing an encrypted communication path between the two applications, "wrapping" the entire application protocol inside the secure link, providing complete privacy for the entire transaction. In this way security-related data such as user identification and password, as well as sensitive transaction information can be protected from unauthorized access while in transit. This section is not a tutorial on TLS/SSL. It contains only information relating to WASD's use of it. See 4.7 - SSL References for further information on TLS/SSL technology.


The terms are used interchangably in this document to represent cryptographic communication technology. They are similar but with important differences. TLS is the more modern and considered the more secure. The term SSL is still in common usage though and retained here even if (by default) WASD now only implements TLS. (When OpenSSL(.org) considers changing its name WASD will toss out the term SSL :-)


WASD implements SSL using a freely available software toolkit supported by the OpenSSL Project.

OpenSSL licensing allows unrestricted commercial and non-commercial use. This toolkit is in use regardless of whether the WASD OpenSSL package, HP SSL for OpenVMS product, or other stand-alone OpenSSL environment is installed. It is always preferable to move to the latest support release of OpenSSL as known bugs in previous versions are progressively addressed (ignoring the issue of new bugs being introduced ;-)

TLS functionality is not supplied with the basic WASD package

In part this is due to the relative bulk of this component, in further part that the updates to each are not necessarily coincident, and also considers potential patent issues and export restrictions on some cryptography technology in some jurisdictions.

Cryptography Software

Be aware that export/import and/or use of cryptography software, or even just providing cryptography hooks, is illegal in some parts of the world. When you re-distribute this package or even email patches/suggestions to the author or other people, please PAY CLOSE ATTENTION TO ANY APPLICABLE EXPORT/IMPORT LAWS. The author of this package is not liable for any violations you make here.

Some Thoughts From R. S. Engelschall

Ralf S. Engelschall (rse@engelschall.com) is the author of the popular Apache mod_ssl package. This section is taken from the mod_ssl read-me and is well-worth some consideration for this and software security issues in general.

You should be very sensible when using cryptography software, because just running an SSL server DOES NOT mean your system is then secure! This is for a number of reasons. The following questions illustrate some of the problems.

  • SSL itself may not be secure. People think it is, do you?
  • Does this code implement SSL correctly?
  • Have the authors of the various components put in back doors?
  • Does the code take appropriate measures to keep private keys private? To what extent is your cooperation in this process required?
  • Is your system physically secure?
  • Is your system appropriately secured from intrusion over the network?
  • Whom do you trust? Do you understand the trust relationship involved in SSL certificates? Do your system administrators?
  • Are your keys, and keys you trust, generated careful[ly] enough to avoid reverse engineering of the private keys?
  • How do you obtain certificates, keys, and the like, securely?
  • Can you trust your users to safeguard their private keys?
  • Can you trust your browser to safeguard its generated private key?

If you can't answer these questions to your personal satisfaction, then you usually have a problem. Even if you can, you may still NOT be secure. Don't blame the authors if it all goes horribly wrong. Use it at your own risk!

4.1 - SSL Functionality Sources

Secure Sockets Layer functionality is easily integrated into WASD and is available from one (or more) of the following sources. See 4.2 - WASD SSL Quick-Start for the basics of installing WASD SSL and 4.3 - SSL Configuration for configuration of various aspects.

  1. The HP SSL1 for OpenVMS product
    Information regarding HP SSL1 (Secure Sockets Layer) for OpenVMS may be found somewhere within this URL: http://h71000.www7.hp.com/openvms/security.html (though it's been a bit of a moving target).
    Perhaps here: http://h71000.www7.hp.com/openvms/security.html#ssl
    Perhaps from the OpenVMS (top-level) documentation URL: http://www.hp.com/go/openvms/doc

    This is provided from the directory

    containing shared libraries, executables and templates for certificate management, etc. If this product is installed and started the WASD installation and update procedures should detect it and provide the option of compiling and/or linking WASD against its shareable libraries.

  2. As a separate, easily integrated WASD OpenSSL package, with OpenSSL object libraries, OpenSSL utility object modules for building executables and WASD support files. It requires no compilation, only linking, and is available for Alpha, Itanium and VAX for VMS version 7.0 up to current. Obtain these from the same source as the main package.

    WASD OpenSSL installation creates an OpenSSL directory in the source area

    WASD_ROOT:[SRC.OPENSSL-n_n_n]   (look for it here)
    containing the OpenSSL copyright notice, object libraries, object modules for building executables, example certificates, and some other support files and documentation.

  3. Using a locally compiled and installed OpenSSL toolkit.

4.2 - WASD SSL Quick-Start

SSL functionality can be installed with a new package, or with an update, or it can be added to an existing non-SSL enabled site. The following steps give a quick outline for support of SSL.

  1. If using the HP SSL1 for OpenVMS product or an already installed OpenSSL toolkit go directly to step 2. To install the WASD OpenSSL package the ZIP archive needs to be restored.
  2. It is then necessary to build the (server and Open)SSL executables.
  3. Once linked the UPDATE.COM procedure will prompt for permission to execute the demonstration/check procedure.

    It is also possible to check the SSL package at any other time using the server demonstration procedure. It is necessary to specify that it is to use the SSL executable. Follow the displayed instructions.


  4. Modification of server startup procedures should not be necessary. If an SSL image is detected during startup it will be used in preference to the standard image.
  5. Modify the WASD_CONFIG_SERVICE configuration file to specify an SSL service. For example the following adds a generic SSL service on port 443.
  6. Shutdown the server completely, then restart.
  7. To check the functionality (on default ports) access the server via
    Standard HTTP

  8. Once the server has been proved functional with the example certificate it is recommended that a server-specific certificate be created using the tools described in 4.4 - Certificate Management. This may then be used by placing it in the appropriate local directory, assigning the WASD_SSL_CERT symbol appropriately before startup.

4.3 - SSL Configuration

The example server startup procedure already contains support for the SSL executable. If this has been used as the basis for startup then an SSL executable will be started automatically, rather than the standard executable. The SSL executable supports both standard HTTP services (ports) and HTTPS services (ports). These must be configured using the [service] parameter. SSL services are distinguished by specifying "https:" in the parameter. The default port for an SSL service is 443.

WASD can configure services using the WASD_CONFIG_GLOBAL [SSL..] directives, the per-service WASD_CONFIG_SERVICE [ServiceSSL..] directives, or the /SSL= qualifier. Configuration precedence is WASD_CONFIG_SERVICE, /SSL= and finally WASD_CONFIG_GLOBAL.


SSL service configuration using the WASD_CONFIG_SERVICE configuration is slightly simpler, with a specific configuration directive for each aspect. (see "WASD VMS Web Services - Install and Config"; 9 - Service Configuration WASD Web Services - Install and Config ). This example illustrates configuring the same services as used in the previous section.


[ServiceSSLversion]  TLSvALL
[ServiceSSLcert]  WASD_ROOT:[local]alpha.pem

[ServiceSSLversion]  SSLv3
[ServiceSSLcert]  WASD_ROOT:[local]beta.pem

4.3.2 - SSL Versions

As WASD uses the OpenSSL package in one distribution or another it largely supports all of the capability of that underlying package. The obsolete SSLv2, and the deprecated SSLv3 are no longer accepted by default. WASD default comprise the TLS family of protocols, at the time of writing, TLSv1, TLSv1.1 and TLSv1.2.

Some older clients employing SSLv3 may fail. Symptoms are dropped connection establishment and WATCH [x]SSL variously showing "SSL routines SSLn_GET_RECORD wrong version number", "SSL routines SSLn_GET_CLIENT_HELLO unknown protocol", possibly others. It is generally considered SSL best-practice not to have SSLv3 enabled but if required may be supported by configuring WASD_CONFIG_GLOBAL [SSLversion] with "SSLv3,TLSvALL", the per-service WASD_CONFIG_SERVICE equivalent, or using the /SSL=(SSLv3,TLSvALL) command line parameter during server startup.

4.3.3 - SSL Ciphers

Ciphers are the algorithms, designed and implemented on mathematical computations, that render the readable plaintext into unreadable ciphertext. Ciphers tend to be available in suites (or families) where variants, usually based on key size and therefore resistence to decryption without a known key, that browsers and otheragents negotiate on and accept when setting up a secure (encrypted) network transports with servers.

Cipher selection is important to the overall security of the supported environment as well as the range of clients and servers that can establish communication due to shared cipher suites. Including only more recent (and technically secure) ciphers can preclude older clients from establishing secure connection, and including older (and perhaps more susceptible to modern attack) ciphers increases site vunerability. Some environments, for example HTTP/2, are quite prescriptive regarding the secure connection, to the point of blacklisting protocol versions and cipher suites no longer considered secure enough.

Fortunately a number of sites provide cipher guidelines based on requirements. The Mozilla Developer Network provides these amongst other useful information on security and server side TLS.


WASD has a default (built-in) functional cipher list that is general in application and relevant to when it was compiled. This in particular and site cipher lists in general, should be reviewed from time to time as opinions and requirements do change.

4.3.4 - (Open)SSL Options

The OpenSSL package provides for various options to be flagged against an TLS/SSL service. WASD sets the (OpenSSL) default options and then allows these to be overwitten/set/reset using hexadecimal values representing bit patterns. OpenSSL defaults are suitable for most sites.

The SSL options directives in global and per-service configuration, and the OPTIONS= keyword for the /SSL= qualifier, accept

Alternatively, the following OpenSSL option mnemonics can be used with a leading "+" to enable, or "-" to disable


4.3.5 - Forward Secrecy

Forward secrecy, sometimes known as perfect forward secrecy (PFS), is a property of key-agreement protocols ensuring that a session key derived from a set of long-term keys cannot be compromised if one of the long-term keys is compromised in the future.


OpenSSL supports forward secrecy using Diffie-Hellman key exchange with elliptic curve cryptography and this relies on generating emphemeral keys based on unique, safe prime numbers. These are expensive to generate and so this is done infrequently, often during software build or installation. In the case of WASD, to maximise flexibility, these numbers are stored in external PEM-format files, by default located in the WASD_ROOT:[LOCAL] directory. These files are only briefly accessed during server startup SSL initialisation and the content later used during network connection SSL negotiation to generate the required ephemeral keys.

PFS requires a small number of elements working in concert

The detail is described in these references


Ephemeral keys are supported beginning with WASD v10.4.1.

Executing the WASD OpenSSL procedure

will generate site-unique files containing 512, 1024 and 2048 bit primes, and optionally copy those files to the WASD_ROOT:[LOCAL] directory. The [.CERT] directory contains files that could be used but unique, locally generated primes are preferable.

Alternatively, generated directly at the command-line using the OpenSSL dhparam utility, as in these examples;

$ openssl dhparam -out dh_param_512.pem 512
$ openssl dhparam -out dh_param_1024.pem 1024
$ openssl dhparam -out dh_param_2048.pem 2048

Key generation can take some considerable time!

The file(s) must be located in the WASD_ROOT:[LOCAL] directory and the file names use the format DH_PARAM_number-of-bits.PEM

Alternatively, files containing emphemeral keys generated freshly with each release, may be copied from the WASD OpenSSL package using


4.3.6 - Session Resumption

When a TLS/SSL connection is initiated an expensive handshake (in terms of time and compute) is required to establish the cryptographic and other elements of the connection. Mitigation of this expense is undertaken by allowing the resumption of a previous session (abbreviating the handshake exchanges) using connection state stored either at the server or at the client.

With Session Tickets being the more modern, flexible and efficient solution to session resumption (and being available cluster-wide) it is recommended that WASD sites disable Session ID caching.

The default maximum period for session reuse is five minutes. This may be set globally using the [SSLsessionLifetime] directive or on a per-service basis using [ServiceSSLsessionLifetime].

To some extent, the relatively long-lived connections and lower concurrency with HTTP/2 means the importance of session resumption in improving request latency and connection overhead is reduced.

4.3.7 - Strict Transport Security

HTTP Strict Transport Security (HSTS) is a security policy mechanism which helps protect sites against protocol downgrade attack and cookie hijacking. It allows web servers to declare that browsers and other complying agents should only interact using secure (TLS) HTTP connections and never via clear-text HTTP. HSTS is an IETF standard specified in RFC 6797.

When global configuration directive [SSLstrictTransSec] is non-zero, or per-service configuration directive [ServiceSSLstrictTransSec] is non-zero, or a path is SET response=sts=<value>, TLS/SSL HTTP responses include a "Strict-Transport-Security: max-age=seconds" header field. Conforming agents note this period and refuse to communicate with the site via clear-text HTTP for the period represented by the integer number of seconds specified.

4.3.8 - SSL Server Certificate

The server certificate is used by the browser to authenticate the server against the server certificate Certificate Authority (CA), in making a secure connection, and in establishing a trust relationship between the browser and server. By default this is located using the WASD_CONFIG_GLOBAL [SSLcert] or WASD_CONFIG_SERVICE [ServiceSSLcert] configuration directive, the WASD_CONFIG_SSL_CERT logical name, or using the /SSL= command-line qualifier, however if required. Each SSL service can have an individual certificate configured as in the example above.

4.3.9 - SSL Private Key

The private key is used to validate and enable the server certificate. A private key is enabled using a secret, a password. It is common practice to embed this (encrypted) password within the private key data. This private key can be appended to the server certificate file, or it can be supplied separately. If provided separately it can be located using the WASD_CONFIG_GLOBAL [SSLkey] or WASD_CONFIG_SERVICE [ServiceSSLkey] configuration directive, tor using the WASD_CONFIG_SSL_KEY logical. When the password is embedded in the private key information it becomes vulnerable to being stolen as an enabled key. For this reason it is possible to provide the password separately and manually.

If the password key is not found with the key during startup the server will request that it be entered at the command-line. This request is made via the HTTPDMON "STATUS:" line (see "WASD VMS Web Services - Install and Config"; 4.11 - OPCOM Logging WASD Web Services - Install and Config ), and if any OPCOM category is enabled via an operator message. If the private key password is not available with the key it is recommended that OPCOM be configured, enabled and monitored at all times.

When a private key password is requested by the server it is supplied using the /DO=SSL=KEY=PASSWORD directive (9.7 - HTTPd Command Line). This must be used at the command line on the same system as the server is executing. The server then prompts for the password.

Enter private key password []:
The password is not echoed. When entered the password is securely supplied to the server and startup progresses. An incorrect password will be reprompted for twice (i.e. up to three attempts are allowed) before the startup continues with the particular service not configured and unavailable. Entering a password consisting of all spaces will cause the server to abort the full startup and exit from the system.

4.3.10 - SSL Virtual Services

Multiple virtual SSL services (https:) sharing the same or individual certificates (and other characteristics) can essentially be configured against any host name (unique IP address or host name alias) and/or port in the same way as standard services (http:).

WASD SSL implements Server Name Indication (SNI), an extension to the TLS protocol that indicates what hostname the client is attempting to connect to at the start of the handshaking process. This allows a server to present multiple certificates on the same IP address and port number and hence allows multiple secure (HTTPS) websites (or any other Service over TLS) to be served off the same IP address without requiring all those sites to use the same certificate.

When the client presents an SNI server name during SSL connection establishment, WASD searches the list of services it is offering for an SSL service (the first hit) operating with a name matching the SNI server name. If matched, the SSL context (certificate, etc.) of that service is used to establish the connection. If not matched, the service the TCP/IP connection originally arrived at is used.

4.3.11 - SSL Access Control

When authorization is in place (3 - Authentication and Authorization) access to username/password controlled data/functionality benefits enormously from the privacy of an authorization environment inherently secured via the encrypted communications of SSL. In addition there is the possibility of authentication via client X.509 certification (4.3.12 - Authorization Using X.509 Certification). SSL may be used as part of the site's access control policy, as whole-of-site, see 3.2 - Authentication Policy, or on a per-path basis (see "WASD VMS Web Services - Install and Config"; 12 - Request Processing Configuration WASD Web Services - Install and Config ).

4.3.12 - Authorization Using X.509 Certification

The server access control functionality (authentication and authorization) allows the use of public key infrastructure (PKI) X.509 v3 client certificates for establishing identity and based on that apply authorization constraints. See 3 - Authentication and Authorization for general information on WASD authorization and 3.4 - Authorization Configuration File for configuring a X509 realm. 4.7 - SSL References provides introductory references on public-key cryptography and PKI.

A client certificate is stored by the browser. During an SSL transaction the server can request that such a certificate be provided. For the initial instance of such a request the browser activates a dialog requesting the user select one of any certificates it has installed. If selected it is transmitted securely to the server which will usually (though optionally not) authenticate its Certificate Authority to establish its integrity. If accepted it can then be used as an authenticated identity. This obviates the use of username/password dialogs.


Neither username/password nor certificate-based authentication addresses security issues related to access to individual machines and stored certificates, or to password confidentiality. Public-key cryptography only verifies that a private key used to sign some data corresponds to the public key in a certificate. It is a user responsibility to protect a machine's physical security and to keep private-key passwords secret.

The initial negotiation and verification of a client certificate is a relatively resource intensive process. Once established however, OpenSSL sessions are usually either stored in a cache or stored encrypted withing the client, reducing subsequent request overheads significantly. Each session has a specified expiry period after which the client is forced to negotiate a new session. This period is adjustable using the "[LT:integer]" and "[TO:integer]" directives described below.

4.3.13 - X.509 Certificate Renegotiation

An X.509 client certificate is requested at either TLS/SSL connection establishment (WASD_CONFIG_GLOBAL [SSLverifyPeer], WASD_CONFIG_SERVICE [ServiceSSLverifyPeer]) or once the request has been made and assessed against authorisation rules. If an X509 realm controls access to the resources then the TLS/SSL connection is queried for an X.509 client certificate to authenticate the client and authorise the access.

This is performed via a TLS/SSL renegotiation and for this the connection must have been cleared of request data. In the case of a HEAD, GET, OPTIONS, etc. request, this already has implicitly occurred by there being no request body. For POST, PROPFIND, PUT, etc. requests, the client most likely already will be transmitting the request body. This (application data) must be absorbed before the client certificate renegotiation can be performed.

In avoiding disruption to the current request, any request body must be buffered (in full, based on the content length specified in the header) before issuing the renegotiation. This consumes memory and potentially large quantities. The default maximum buffer space is 1MB. The maximum request body size and hence maximum memory accomodated can be configured using the per-service WASD_CONFIG_SERVICE [ServiceSSLverifyDataMax] directive, or the global WASD_CONFIG_GLOBAL configuration directive [SSLverifyDataMax].

Where a request with a body exceeds the maximum allowed buffer space the authorisation fails. This can be observed using WATCH. Where very large files are being sent the only solution is to first authenticate with a request without a body (e.g. using OPTIONS) then using the persistent connection and associated X.509 authentication perform the PUT or POST.

4.3.14 - Features

WASD provides a range of capabilities when using X.509 client certificates.

4.3.15 - Subject Alternative Name and Other Extensions

The basic syntax for this field is the full extension name, and the short-hand equivalent.

/VMS/* r+w,param="[ru:X509v3_subject_Alternative_Name]"
/VMS/* r+w,param="[ru:X509v3_SAN]"

The Subject Alternative Name (SAN) extension (in common with many others) may contain multiple data elements, each with a leading name, a colon, and a (if multi line) carriage-control terminated value. WASD parses these into unqiue fields using keywords fixed in function SesolaCertKeyword() and the site configurable logical name WASD_X509_EXTENSION_KEYWORDS value. To select one of these fields, for example the common (Microsoft) user principal name (UPN), append the required field name to the extension name as shown in the following example (includes "shorthand" equivalents, along with the underscore and equate variants). Note that the identifying name match is not case sensitive.

/VMS/* r+w,param="[ru:X509V3_Subject_Alternative_Name_UserPrincipalName]"
/VMS/* r+w,param="[ru:X509V3_Subject_Alternative_Name=UserPrincipalName]"
/VMS/* r+w,param="[ru:X509v3_SAN_UPN]"
/VMS/* r+w,param="[ru:X509v3_SAN=UPN]"
/VMS/* r+w,param="[ru:X509V3_Subject_Alternative_Name_rfc822Name]"
/VMS/* r+w,param="[ru:X509V3_Subject_Alternative_Name=rfc822Name]"
/VMS/* r+w,param="[ru:X509v3_SAN_822]"
/VMS/* r+w,param="[ru:X509v3_SAN=822]"

Object Identifiers (OIDs) may be used for either record and field name (if an unknown otherName) by prefixing with "OID_". For example, the SAN may be alternatively selected, and the (Microsoft) UPN, as in the following examples.

/VMS/* r+w,param="[ru:OID_2_5_29_17]"
/VMS/* r+w,param="[ru:OID_2_5_29_17_UPN]"
/VMS/* r+w,param="[ru:OID_2_5_29_17=UPN]"
/VMS/* r+w,param="[ru:X509v3_SAN_OID_1_3_6_1_20_2_3]"
/VMS/* r+w,param="[ru:X509v3_SAN_OID=1_3_6_1_20_2_3]"

Extension Visibility

X509 certificate extensions are in general visible from WATCH and accessible via CGI variables (when enabled using SET SSLCGI=apache_mod_ssl_extens and SSLCGI=apache_mod_ssl_client path mappings). The identifying names derived from X509 extensions are built of the alphanumerics in the element names. Non-alphanumerics (e.g. spaces) have underscores substituted. Multiple underscores are compressed into singles. Where elements have identical names the first multiple has TWO underscores and the digit two appended, the second mutiple, two underscores and three appended, etc.

4.3.16 - X509 Configuration

Of course, the WASD OpenSSL component must be installed and in use to apply client X.509 certificate authorization. There is general server setup, then per-service and per-resource configuration.

General Setup

Client certificate authorization has reasonable defaults. If some aspect requires site refinement the WASD_CONFIG_GLOBAL [SSL..] directives (see WASD Web Services - Install and Config ) or command-line /SSL= qualifier parameters can provide per-server defaults.

The location of the CA verification file can also be determined using the logical name WASD_CONFIG_SSL_CAFILE. The order of precedence for using these specifications is

  1. per-service configuration using WASD_CONFIG_SERVICE or WASD_CONFIG_GLOBAL
  2. per-server using /SSL=CAFILE=filename
  3. per-server using WASD_CONFIG_SSL_CAFILE

By Service

The WASD_CONFIG_SERVICE directive is provided for per-service CA file specification, if necessary allowing different services to accept a different mix of CAs.

[ServiceSSLVerifyPeer]  enabled

By Resource

Client certificate authorization is probably most usefully applied on a per-resource (per-request-path) basis using WASD_CONFIG_AUTH configuration file rules. Of course, per-resource control also applies to services that always require a client certificate (the only difference is the certificate has already been negotiated for during the initial connection handshake). The reserved realm name "X509" activates client certificate authentication when a rule belonging to that realm is triggered. The following example shows such a rule providing read access to those possessing any verified certificate.

/path/requiring/cert/* r

Optional directives may be supplied to the X.509 authenticator controlling what mode the certificate is accepted in, as well a further access-restriction rules on specifically which certificates may or may not be accepted for authorization. Such directives are passed via the "param=" mechanism. The following real-life example shows a script path requiring a mandatory certificate, but not necessarily having the CA verified. This would allow a certificate display service to be established, the "[to:EXPIRED]" directive forcing the client to explicitly select a certificate with each access.

/cgi-bin/client_cert_details r,param="[vf:OPTIONAL][to:EXPIRED]"

A number of such directives are available controlling some aspects of the certificate negotiation and verification. The "[LT:integer]" directive causes a verified certificate selection to continue to be valid for the specified period as long as requests continue during that period (lifetime is reset with each access).

Optional "param=" passed conditionals may also be used to provide additional filtering on which certificates may or may not be used against the particular path. This is based on pattern matching against client certificate components.

These function and can be used in a similar fashion to mapping rule conditionals (see WASD Web Services - Install and Config document, "Conditional Configuration" section). This includes the logical ORing, ANDing and negating of conditionals. Asterisk wildcards match any zero or more characters, percent characters any single character. Matching is case-insensitive.

Note that the "IS:" and "SU:" conditionals each have a specific-record and an entire-field mode. If the conditional string begins with a slash then it is considered to be a match against a specified record contents within the field. If it begins with a wildcard then it is matched against the entire field contents. Certificate DN records recognised by WASD,

/C= countryName
/ST= stateOrProvinceName
/SP= stateOrProvinceName
/L= localityName
/O= organizationName
/OU= organizationalUnitName
/CN= commonName
/T= title
/I= initials
/G= givenName
/S= surname
/D= description
/UID= uniqueIdentifier
/Email= pkcs9_emailAddress

The following (fairly contrived) examples provide an illustration of the basics of X509 conditionals. When matching against Issuer and Subject DNs some knowlege of their contents and structure is required (see 4.7 - SSL References for some basic resources).

# only give "VeriSign"ed ones access
/controlled/path1/* r+w,param="[IS:/O=VeriSign\ Inc.]"
# only give non-"VeriSign"ed ones access
/controlled/path2/* r+w,param="[!IS:/O=VeriSign\ Inc.]"
# only allow 128 bit keys using RC4-MD5 access
/controlled/path3/* r+w,param="[KS:128][CI:RC4-MD5]"
# only give a "Thawte"-signed client based in Australia
# with the following email address access
/controlled/path4/* r+w,param="\
[IS:*/O=Thawte\ Consulting\ cc/*]\
# use the subject DN common-name record as the remote-user name
# furthermore, restrict the CA's allowed to be used this way
/VMS/* r+w,param="[RU:/CN=][IS:/O=WASD\ CA\ Cert]"

Of course, access control via group membership is also available. The effective username for the list is the 32 digit fingerprint of the client certificate (shown as REMOTE_USER IN the first example of 4.3.18 - X.509 Authorization CGI Variables), or the Subject DN record as specified using the [RU:/record=] directive. This may be entered into simple lists as part of a group of which membership then controls access to the resource. The following examples show the contents of simple list files containing the X.509 fingerprints, derived remote-user names, and the required WASD_CONFIG_AUTH realm entries.

# (a file of X.509 fingerprints for access to "/path/requiring/cert/")
106C8342890A1703AAA517317B145BF7  mark.daniel@wasd.vsm.com.au
6ADA07108C20338ADDC3613D6D8B159D  just.another@where.ever.com

# (a file of X.509 remote-user names derived using [RU:/CN=]
Mark_Daniel mark.daniel@wasd.vsm.com.au
Just_Another just.another@where.ever.com

/path/requiring/cert/* r+w

/path/requiring/cn/* r+w

In a similar fashion the effective username can be placed in an access restriction list. The following configuration would only allow the user of the certificate access to the specified resources. Other verified certificate holders would be denied access.

/httpd/-/admin/* ~106C8342890A1703AAA517317B145BF7,r+w
/wasd_root/local/* ~106C8342890A1703AAA517317B145BF7,r+w

/other/path/* ~Mark_Daniel,r+w,param="[ru:/cn=]"
/yet/another/path/* ~Just_Another,r+w,param="[ru:/cn=]"

4.3.17 - Certificate Authority Verification File

For the CA certificate component of the client certificate to be verified as being what it claims to be (and thus establishing the integrity of the client certificate) a list of such certificates must be provided for comparison purposes. For WASD this list is contained in a single, plain-text file variously specified using either the WASD_CONFIG_SSL_CAFILE logical or per-service "[ServiceSSLclientCAfile]" directives, or the global [SSLverifyPeerCAFile] directive.

Copies of CA certificates are available for such purposes. The PEM copies (base-64 encoded versions of the binary certificate) can be placed into this file using any desired text editor. Comments may be inserted by prefixing with the "#" character. For WASD this would be best stored in the WASD_ROOT:[LOCAL] directory, or site equivalent.

An example of how such a file appears is provided below (bulk of the file has been 8< snipped 8< for bevity).

## Bundle of CA Root Certificates
## Certificate data from Mozilla as of: Wed Apr 20 03:12:05 2016
## This is a bundle of X.509 certificates of public Certificate Authorities
## (CA). These were automatically extracted from Mozilla's root certificates
## file (certdata.txt).  This file can be found in the mozilla source tree:
## http://hg.mozilla.org/releases/mozilla-release/raw-file/default/security/nss/lib/ckfw/builtins/certdata.txt
## It contains the certificates in PEM format and therefore
## can be directly used with curl / libcurl / php_curl, or with
## an Apache+mod_ssl webserver for SSL client authentication.
## Just configure this file as the SSLCACertificateFile.
## Conversion done with mk-ca-bundle.pl version 1.25.
## SHA1: 5df367cda83086392e1acdf22bfef00c48d5eba6

GlobalSign Root CA
8< snip 8<

The WASD OpenSSL package provides an example CA verification file. The exact date and source can be found in the opening commentary of the file itself. The contents of this file easily can be pared down to the minimum certificates required for any given site.

The bundle may be refreshed at any time using any reliable source. The cURL project provides such a resource suitable for its own use, Apache mod_ssl and WASD. This is sourced from the root certificates used by the Mozilla Foundation for its Firefox product (and others). Mozilla uses a non-PEM format source which must be converted before use by WASD. The cURL site provides this already converted for use with its own utility and made available as a general resource.


Download the bundle using a command-line tool as in this example

$ curl -o ca-bundle_crt.txt https://curl.haxx.se/ca/cacert.pem
or as a save-as dialogue click from your favourite browser and then a transfer onto the VMS system.

4.3.18 - X.509 Authorization CGI Variables

CGI variables specific to client certificate authorization are always generated for use by scripts and SSI documents. These along with the general WASD authorization variables are shown in the example below. Note, that due to length of particular items some in this example are displayed wrapped.

WWW_AUTH_USER == "Mark Daniel, mark.daniel@wasd.vsm.com.au"
WWW_AUTH_X509_FINGERPRINT == "10:6C:83:42:89:0A:17:03:AA:A5:17:31:7B:14:5B:F7"
WWW_AUTH_X509_ISSUER == "/O=VeriSign, Inc./OU=VeriSign Trust
Network/OU=www.verisign.com/repository/RPA Incorp. By
Ref.,LIAB.LTD(c)98/CN=VeriSign Class 1 CA Individual Subscriber-Persona Not
WWW_AUTH_X509_KEYSIZE == "128"
WWW_AUTH_X509_SUBJECT == "/O=VeriSign, Inc./OU=VeriSign Trust
Network/OU=www.verisign.com/repository/RPA Incorp. by
Ref.,LIAB.LTD(c)98/OU=Persona Not Validated/OU=Digital ID Class 1 - Netscape
/CN=Mark Daniel/Email=mark.daniel@wasd.vsm.com.au"
WWW_REMOTE_USER == "106C8342890A1703AAA517317B145BF7"

Other CGI variables optionally may be enabled using WASD_CONFIG_MAP mapping rules. See 4.5 - SSL CGI Variables. Specific client certificate variables providing the details of such certificates are available with SSLCGI=apache_mod_ssl. These are of course in addition to the more general apache_mod_ssl variables described in the above section. Note that where some ASN.1 records are duplicated (as in SSL_CLIENT_S_DN) some variables will contain newline characters (0x10) between those elements (e.g. SSL_CLIENT_S_DN_OU). The line breaks in this example do not necesarily reflect those characters.

WWW_SSL_CLIENT_A_KEY == "rsaEncryption"
WWW_SSL_CLIENT_A_SIG == "md5WithRSAEncryption"
WWW_SSL_CLIENT_I_DN == "/O=VeriSign, Inc./OU=VeriSign Trust Network
/OU=www.verisign.com/repository/RPA Incorp. By Ref.,LIAB.LTD(c)98
/CN=VeriSign Class 1 CA Individual Subscriber-Persona Not Validated"
WWW_SSL_CLIENT_I_DN_CN == "VeriSign Class 1 CA Individual Subscriber-Persona
Not Validated"
WWW_SSL_CLIENT_I_DN_O == "VeriSign, Inc."
WWW_SSL_CLIENT_I_DN_OU == "VeriSign Trust Network
www.verisign.com/repository/RPA Incorp. By Ref.,LIAB.LTD(c)98"
WWW_SSL_CLIENT_S_DN == "/O=VeriSign, Inc./OU=VeriSign Trust Network
/OU=www.verisign.com/repository/RPA Incorp. by Ref.,LIAB.LTD(c)98
/OU=Persona Not Validated/OU=Digital ID Class 1 - Netscape
/CN=Mark Daniel/Email=mark.daniel@wasd.vsm.com.au"
WWW_SSL_CLIENT_S_DN_CN == "Mark Daniel"
WWW_SSL_CLIENT_S_DN_EMAIL == "mark.daniel@wasd.vsm.com.au"
WWW_SSL_CLIENT_S_DN_O == "VeriSign, Inc."
WWW_SSL_CLIENT_S_DN_OU == "VeriSign Trust Network
www.verisign.com/repository/RPA Incorp. by Ref.,LIAB.LTD(c)98
Persona Not Validated.Digital ID Class 1 - Netscape"
WWW_SSL_CLIENT_V_END == "Feb 10 23:59:59 2001 GMT"
WWW_SSL_CLIENT_V_START == "Dec 12 00:00:00 2000 GMT"

4.4 - Certificate Management

This is not a tutorial on X.509 certificates and their management. Refer to the listed references, 4.7 - SSL References, for further information on this aspect. It does provide some basic guidelines.

Certificates identify something or someone, associating a public cryptographic key with the identity of the certificate holder. It includes a distinguished name, identification and signature of the certificate authority (CA, the issuer and guarantor of the certificate), and the period for which the certificate is valid, possibly with other, additional information.

The three types of certificates of interest here should not be confused.

The various OpenSSL tools are available for management of all of these certificate types in each of the three SSL environments.

4.4.1 - Server Certificate

The server uses a certificate to establish its identity during the initial phase of the SSL protocol exchange. Each server should have a unique certificate. An example certificate is provided with the WASD OpenSSL package. If this is not available (for instance when using the HP SSL1 for OpenVMS product) then the server will fallback to an internal, default certificate that allows SSL functionality even when no external certification is available. If a "live" SSL site is required a unique certificate issued by a third-party Certificate Authority is desirable.

A working alternative to obtaining one of these certificates is provided by the WASD support DCL procedures, which are quick hacks to ease the production of certificates on an ad hoc basis. In all cases it is preferable to directly use the utilities provided with OpenSSL, but the documentation tends to be rather sparse.

The first requirement may be a tailored "Certificate Authority" certificate. As the Certificate Authority is non-authoritative (not trying to be too oxymoronic, i.e. not a well-known CA) these certificates have little value except to allow SSL transactions to be established with trusting clients. More commonly "Server Certificates" for specific host names are required.

Loading Authority Certificates

CA certificates can be loaded into browsers to allow sites using that CA to be accessed by that browser without further dialog. Browsers commonly invoke a server certificate load dialog when encountering a site using a valid but unknown server certificate.

A manual load is accomplished by requesting the certificate in a format appropriate to the particular browser. This triggers a browser dialog with the user to confirm or refuse the loading of that certificate into the browser Certificate Authority database.

To facilitate loading CA certificates into a browser ensure the following entries are contained in the HTTP$CONFIG configuration file:

/httpd/-/binary.gif  [BIN]  application/x-x509-ca-cert

.CRT  application/x-x509-ca-cert  -  DER certifcate (MSIE)
.PEM  application/x-x509-ca-cert  -  Privacy Enhanced Mail certificate

Then just provide a link to the required certificate file(s), and click.

Changing Server Certificates

If a site's server (or CA certificate) is changed and the server restarted any executing browsers will probably complain (Netscape Navigator reports an I/O error). In this case open the browser's certificate database and delete any relevant, permanently stored certificate entry, then close and restart the browser. The next access should initiate the server certificate dialog, or the CA certificate may be explicitly reloaded.

4.4.2 - Client Certificate

As with server certificates, client certficates are best obtained from a recognised Certificate Authority. However, for testing and experimental purposes WASD provides some elementary CGI scripts and DCL procedures to assist in locally generating X.509 client certificates and installing them into user browsers.

Manual Generation

The OpenSSL CA certificate generation utility can be used at the command line to process a CSR. That CSR could have been generated via an online HTML form.

Command-Line Generation

A basic DCL procedure providing the necessary Certificate Signing Request (CSR) then subsequent certificate generation and optional PKSC#12 conversion is provided by


Semi-Automatic Generation

Using this approach the user generates a Certificate Signing Request (CSR) online, which is then further processed off-line, at the discretion of the site administrator. Only Netscape browsers are supported for what is described below.

  1. Provide an HTML form with the appropriate fields for each of the required ASN.1 fields used in X.509 certificates, plus a special, Netscape-sepcific one named <KEYGEN>, which allows the creation of a user's private-key. The user completes the elements of that form and when submitted the contents are emailed to the site administrator. A CSR can be freely transmitted as open text because it is secured by the private-key generated and only stored on the user's local machine.
  2. The site administrator receives such a CSR by email. At that person's discretion and availability the CSR is input (cut-and-paste to eliminate errors) to a form activating a local CGI script requiring authorization for activation. The CGI script processes the CSR submitted by the form and creates using the OpenSSL CA certificate signing utility to generate a certificate (or an error if there is a problem).
  3. If a client certificate is successfully generated it can either be delivered back to the user via email, for local saving and import, or made available for a short period via the Web for the user to collect (via a file with the content-type of "application/x-x509-user-cert"). Notification of such availability could be made using email.

A basic DCL procedure providing such a facility is


This semi-automatic method would probably be the author's preference over the on-demand approach (see below).

Generation On-Demand

Automatic, on-demand client certificate generation allows any user (subject to access controls) to generate a client certificate automatically via an online service. While this may not generally be a useful thing for a site to provide there may be occasions for its use. It is a three part process. Only Netscape browsers are supported for what is described below.

  1. As with the semi-automatic approach an HTML form allows a user to input and submit certificate details.
  2. The submitted form activates a CGI script which collates the form details generating the Certificate Signing Request (CSR). The CSR is then used directly by the OpenSSL CA certificate signing utility to generate a certificate (or an error if there is a problem).
  3. If a client certificate is successfully generated it is delivered back to the browser with a content-type of "application/x-x509-user-cert" which results in the browser installing it in its certificate database.
A basic DCL procedure providing such a facility is
(and yes, it's the same procedure as used with the semi-automatic approach, just configured differently).

4.4.3 - Certificate Signing Request

Recognised Certificate Authorities (CAs) such as Thawte and VeriSign publish lists of requirements for obtaining a server certificate. These often include such documents required to prove organisational name and the right to use the domain name being requested. Check the particular vendor for the exact requirements.

In addition, a document containing the site's private key is required. This is known as the Certificate Signing Request (CSR) and must be generated digitally at the originating site.

Using the HP SSL1 for OpenVMS product "SSL Certificate Tool" described in 4.4 - Certificate Management a CSR can easily be generated using its menu-driven interface. The alternative is using a command-line interface tool.

The following instructions provide the basics for generating a CSR at the command-line in the WASD and generally the any OpenSSL environment (including the HP SSL1 for OpenVMS product).

  1. Change to a secure directory. The following is a suggestion.
  2. Assign a foreign verb for the OPENSSL application. The location may vary a little depending on which OpenSSL package you have installed.

    When using the HP SSL1 for OpenVMS product or other OpenSSL toolkit the verb may already be available.


  3. Specify a source of lots of "random" data (can be any big file for the purposes of this exercise).
  4. Find the template configuration file. You will need to specify this location in a step described below. Should be something like the following.
  5. Generate your private key (RANDFILE data is used by this). The output from this looks something like what's shown. Notice the pass phrase prompts. This is your private key, don't forget it!
    Generating RSA private key, 1024 bit long modulus
    e is 65537 (0x10001)
    Enter PEM pass phrase:
    Verifying password - Enter PEM pass phrase:
  6. Generate the Certificate Signing Request using syntax similar to the following (this is where you are required to specify the location of the configuration template). Note that there are quite a few fields - GET THEM RIGHT! They need to be unique and local - they're your distinguishing name (DN). "Common Name" is the host you want the certificate for. It can be a fully qualifier host name (e.g. "klaatu.local.net"), or a local wildcard (e.g. "*.local.net") for which you may pay more.
    Using configuration from template.cnf
    Enter PEM pass phrase:
    You are about to be asked to enter information that will be
    incorporated into your certificate request.
    What you are about to enter is what is called a Distinguished Name
    or a DN.
    There are quite a few fields but you can leave some blank
    For some fields there will be a default value,
    If you enter '.', the field will be left blank.
    Country Name (2 letter code) [AU]:AU
    State or Province Name (full name) [Some-State]:South Australia
    Locality Name (eg, city) []:Adelaide
    Organization Name (eg, company) [Internet Widgits Pty Ltd]:Example
    Organizational Unit Name (eg, section) []:WASD
    Common Name (eg, YOUR name) []:klaatu.local.net
    Email Address []:Mark.Daniel@wasd.vsm.com.au
    Please enter the following 'extra' attributes
    to be sent with your certificate request
    A challenge password []:
    An optional company name []:
  7. That's it! You should have two files in your default directory.
    SERVER.CSR;1               2  14-MAR-2002 04:38:26.15
    SERVER.KEY;1               2  14-MAR-2002 04:31:38.76

    Keep the SERVER.KEY file secure. You'll need it when you receive the certificate back from the CA.

    The SERVER.CSR is what you send to the CA (usually by mail or Web form). It looks something like the following


    You can see the details of this file using


After Receiving The Certificate

Once the signed certificate has been issued by the Certificate Authority it can be placed directly into the server configuration directory, usually WASD_ROOT:[LOCAL], and configured for use from there. Using the certificate direct from the CA requires that the private key password be given to the server each time (4.3.9 - SSL Private Key). It is possible to embed the password into the certificate key so that this is not required.

Remember to keep original files secure, only work on copies!

  1. Assign a foreign verb for the OPENSSL application. The location may vary a little depending on which OpenSSL package you have installed.

    When using the HP SSL1 for OpenVMS product or other OpenSSL toolkit the verb may already be available.


  2. Go to wherever you want to do the work.
  3. You may require these additional steps (based on user experience):
  4. Using the original key file embed your password into a copy. When prompted "Enter PEM pass phrase:" enter the password.
    $ OPENSSL rsa -in SERVER.KEY -out WORK.PEM
  5. Append this password-embedded key file to your certificate file.
  6. Delete the temporary file.

4.5 - SSL CGI Variables

CGI variables specific to SSL transactions optionally may be enabled using WASD_CONFIG_MAP mapping rules. (See WASD Web Services - Install and Config document, "Request Processing Configuration" section.) The may be done on a specific per-path or general CGI basis. Two variations are available, one reflecting Purveyor Secure Web Server style variables, the other the Apache mod_ssl style. In the following examples, due to length of particular items, some in this example are displayed wrapped. Also, where some ASN.1 records are duplicated (as in SSL_CLIENT_S_DN), some variables will contain newline characters (0x10) between those elements (e.g. SSL_CLIENT_S_DN_OU). The line breaks in the examples do not necesarily reflect those characters.

set /path/* SSLCGI=apache_mod_ssl

WWW_SSL_SERVER_A_KEY == "rsaEncryption"
WWW_SSL_SERVER_A_SIG == "sha1WithRSAEncryption"
/OU=OpenSSL 1.0.1j Testing Only/CN=WASD VMS Web Services
WWW_SSL_SERVER_I_DN_EMAIL == "Mark.Daniel@wasd.vsm.com.au"
WWW_SSL_SERVER_I_DN_L == "Adelaide"
WWW_SSL_SERVER_I_DN_OU == "OpenSSL 1.0.1j Testing Only"
WWW_SSL_SERVER_S_DN == "/C=AU/ST=SA/L=Adelaide/O=WASD Server Cert
/OU=OpenSSL 1.0.1j Testing Only/CN=WASD VMS Web Services
WWW_SSL_SERVER_S_DN_EMAIL == "Mark.Daniel@wasd.vsm.com.au"
WWW_SSL_SERVER_S_DN_L == "Adelaide"
WWW_SSL_SERVER_S_DN_OU == "OpenSSL 1.0.1j Testing Only"
WWW_SSL_SERVER_V_END == "Nov 16 13:02:05 2024 GMT"
WWW_SSL_SERVER_V_START == "Nov 19 13:02:05 2014 GMT"
WWW_SSL_SESSION_ID == "b72812e716f1f20c983935db08ad8ede3af786ffd505b4a2d707eddf8d07dcd9"
WWW_SSL_VERSION_LIBRARY == "OpenSSL 1.0.1j 15 Oct 2014"

The Apache mod_ssl client certificate details described in 4.3.18 - X.509 Authorization CGI Variables above are not shown in the above example but would be included if the request was X.509 authenticated.

X509 certificate extensions are in general visible from WATCH and accessible via CGI variables when enabled using SET SSLCGI=apache_mod_ssl_extens and SSLCGI=apache_mod_ssl_client path mappings.

set /path/* SSLCGI=purveyor

WWW_SSL_CLIENT_CA == "/O=VeriSign, Inc./OU=VeriSign Trust Network
/OU=www.verisign.com/repository/RPA Incorp. By Ref.,LIAB.LTD(c)98
/CN=VeriSign Class 1 CA Individual Subscriber-Persona Not Validated"
WWW_SSL_CLIENT_DN == "/O=VeriSign, Inc./OU=VeriSign Trust Network
/OU=www.verisign.com/repository/RPA Incorp. by Ref.,LIAB.LTD(c)98
/OU=Persona Not Validated/OU=Digital ID Class 1 - Netscape
/CN=Mark Daniel/Email=mark.daniel@wasd.vsm.com.au"
/OU=OpenSSL 1.0.1j Testing Only/CN=WASD VMS Web Services
WWW_SSL_SERVER_DN == "/C=AU/ST=SA/L=Adelaide/O=WASD Server Cert
/OU=OpenSSL 1.0.1j Testing Only/CN=WASD VMS Web Services

Note that this example also shows SSL_CLIENT_... variables. These will only be present if the request is X.509 certificate authenticated.

4.6 - SSL Service Evaluation

This section is just the barest introduction to a significant topic.

Qualys SSL Lab

"How well do you know SSL? If you want to learn more about the technology that protects the Internet, you've come to the right place."


Not necessarily an endorsement by WASD but a useful resource in itself.

Provides a free and unencumbered, comprehensive SSL Server test service

reporting on certificate status, protocol version, cipher suites, handshakes with various simulated clients, and protocol details including known vulnerabilities. It also summarises the report with a colour-coded rating.

At Home

So to speak.

The OPENSSL command-line application

provides a configurable client for checking and testing various aspects of server configuration and behaviour. The basic operation represented by the command-line
$ openssl s_client -host <host name or address> -port 443
provides a comprehensive report including certificates and certificate chain, the protocol version and cipher negotiated, along with more esoteric elements of TLS/SSL. Some data have been 8< snipped 8< for brevity in the following example.
$ openssl s_client -host klaatu.private -port 443
WARNING: can't open config file: SSLROOT:[000000]openssl.cnf
depth=0 C = AU, ST = SA, L = Adelaide, O = WASD Server Cert, OU 8< snip 8< 
verify error:num=20:unable to get local issuer certificate
verify return:1
depth=0 C = AU, ST = SA, L = Adelaide, O = WASD Server Cert, OU 8< snip 8< 
verify error:num=27:certificate not trusted
verify return:1
depth=0 C = AU, ST = SA, L = Adelaide, O = WASD Server Cert, OU 8< snip 8<
verify error:num=21:unable to verify the first certificate
verify return:1
Certificate chain
 0 s:/C=AU/ST=SA/L=Adelaide/O=WASD Server Cert/OU=OpenSSL 1.0.1 8< snip 8< 
   i:/C=AU/ST=SA/L=Adelaide/O=WASD CA Cert/OU=OpenSSL 1.0.1j Te 8< snip 8< 
Server certificate
8< snip 8< 
subject=/C=AU/ST=SA/L=Adelaide/O=WASD Server Cert/OU=OpenSSL 1. 8< snip 8<
issuer=/C=AU/ST=SA/L=Adelaide/O=WASD CA Cert/OU=OpenSSL 1.0.1j  8< snip 8< 
No client certificate CA names sent
SSL handshake has read 1791 bytes and written 625 bytes
New, TLSv1/SSLv3, Cipher is AES256-GCM-SHA384
Server public key is 2048 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
    Protocol  : TLSv1.2
    Cipher    : AES256-GCM-SHA384
    Session-ID: 61FEC1629DA3E675AA124223CDB9CB5AB7701D872E85E15 8< snip 8<
    Master-Key: F4260DFE9A7370B3EA85D22D89DB8A7925C655159C3C509 8< snip 8< 
    Key-Arg   : None
    PSK identity: None
    PSK identity hint: None
    SRP username: None
    TLS session ticket lifetime hint: 300 (seconds)
    TLS session ticket:
    0000 - 63 d6 2a 84 19 fe f6 9a-13 60 e1 8a 65 dd f9 fc   c.*......`..e...
8< snip 8<
    00a0 - 9a 2d 29 9b 8e aa ab 69-11 0d 45 ed 63 48 f5 4f   .-)....i..E.cH.O

    Start Time: 1415828121
    Timeout   : 300 (sec)
    Verify return code: 21 (unable to verify the first certificate)
bad select 38

The "bad select 38" is a VMS (C-RTL) limitation and on another platform the default use of -s_client will prompt for an HTTP request line, send that to the server, and report the response.

Checking whether a specific protocol version is enabled on a site:

$ openssl s_client -ssl2 -host <host name or address> -port 443
$ openssl s_client -ssl3 -host <host name or address> -port 443
$ openssl s_client -tls1 -host <host name or address> -port 443
$ openssl s_client -tls1_1 -host <host name or address> -port 443
$ openssl s_client -tls1_2 -host <host name or address> -port 443

The following example shows a server test where the protocol version is NOT supported.

$ openssl s_client -ssl3 -host klaatu.private -port 443
8< snip 8<
SSL handshake has read 7 bytes and written 0 bytes
New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
    Protocol  : SSLv3
    Cipher    : 0000
8< snip 8<

4.7 - SSL References

The following provide a starting-point for investigating SSL and OpenSSL further (verified available at time of publication).

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