Security Target
for
HOB RD VPN
blue edition
Document version:
2.2
Product version:
2.1 10.5397
Issue:
January 15, 2014
HOB GmbH & Co. KG
Schwadermuehlstrasse 3
90556 Cadolzburg
Germany
Ph. +49-9103-715-0
Fax +49-9103-715-271
E-mail: support@hob.de
Internet: http://www.hobsoft.com
Table of Contents
Symbols and Conventions....................................................................................................4
Document history.................................................................................................................4
Abbreviations and Acronyms................................................................................................4
1 INTRODUCTION.................................................................................................................7
1.1 Security Target and CC Identification...........................................................................7
1.2 TOE Identification...........................................................................................................7
1.3 TOE Type.........................................................................................................................7
1.4 TOE Overview.................................................................................................................7
1.4.1 Required Hardware and Software..............................................................................8
1.4.1.1 Java Virtual Machines..........................................................................................8
1.4.1.2 Browsers..............................................................................................................9
1.4.1.3 LDAP...................................................................................................................9
1.4.2 Intended Method of Use.............................................................................................9
1.4.3 Major Security Features...........................................................................................10
1.5 TOE Description............................................................................................................10
1.5.1 Product operation.....................................................................................................10
1.5.1.1 WSP..................................................................................................................11
1.5.1.2 Client-side..........................................................................................................12
1.5.1.2.1 JWT connection..........................................................................................13
1.5.1.2.2 Web Server Gate operation of HTTP handler.............................................14
1.5.1.3 HOBLink Security Manager...............................................................................14
1.5.2 TOE boundaries.......................................................................................................14
1.5.2.1 Physical.............................................................................................................14
1.5.2.2 Logical...............................................................................................................15
1.5.2.3 Configurations...................................................................................................16
2 CC CONFORMANCE CLAIM............................................................................................17
3 SECURITY PROBLEM DEFINITION................................................................................17
3.1 Threat Environment......................................................................................................17
3.1.1 Assets......................................................................................................................17
3.1.2 Threat Agents...........................................................................................................17
3.1.3 Threats countered by the TOE.................................................................................18
3.1.4 Threats countered by the TOE environment.............................................................18
3.2 Assumptions.................................................................................................................18
3.2.1 Environment of use of the TOE................................................................................18
3.2.1.1 Physical.............................................................................................................18
3.2.1.2 Personnel..........................................................................................................18
3.2.1.3 Procedural.........................................................................................................19
3.2.1.4 Connectivity.......................................................................................................19
3.3 Organizational Security Policies.................................................................................20
4 SECURITY OBJECTIVES.................................................................................................20
4.1 Objectives for the TOE.................................................................................................20
4.2 Objectives for the Operational Environment..............................................................21
4.3 Security Objectives Rationale.....................................................................................22
4.3.1 Coverage..................................................................................................................22
4.3.2 Sufficiency................................................................................................................23
5 EXTENDED COMPONENTS DEFINITION.......................................................................27
5.1 Class FMT: Security management..............................................................................28
5.1.1 TOE Configuration (FMT_CFG)...............................................................................28
5.1.1.1 FMT_CFG.1 - Configuration of security functions..............................................28
5.1.1.2 FMT_CFG.2 - Configuration value initialization..................................................29
6 SECURITY REQUIREMENTS...........................................................................................29
i HOB GmbH & Co. KG
6.1 TOE Security Functional Requirements.....................................................................29
6.1.1 Information flow control policy models......................................................................30
6.1.1.1 Information flow control policy model (JWT)......................................................30
6.1.1.2 Information flow control policy model (HTTPS)..................................................31
6.1.1.3 Information flow control policy model (WSP).....................................................31
6.1.2 Cryptographic support..............................................................................................32
6.1.2.1 Cryptographic key generation (FCS_CKM.1(RNG))...........................................32
6.1.2.2 Cryptographic key generation (FCS_CKM.1(RSA))...........................................32
6.1.2.3 Cryptographic key distribution (FCS_CKM.2)....................................................33
6.1.2.4 Cryptographic key destruction (FCS_CKM.4)....................................................34
6.1.2.5 Cryptographic operation (FCS_COP.1(TLS))....................................................34
6.1.2.6 Cryptographic operation (FCS_COP.1(CERT)).................................................35
6.1.2.7 Random number generation (Class DRG.3) (FCS_RNG.1)...............................35
6.1.3 JWT TLS connectivity..............................................................................................36
6.1.3.1 Subset information flow control (FDP_IFC.1(JWT))...........................................36
6.1.3.2 Simple security attributes (FDP_IFF.1(JWT))....................................................37
6.1.3.3 Basic internal transfer protection (FDP_ITT.1)...................................................38
6.1.3.4 Integrity monitoring (FDP_ITT.3).......................................................................38
6.1.3.5 Configuration value initialization (FMT_CFG.2(JWT)).......................................39
6.1.4 HTTPS connectivity..................................................................................................39
6.1.4.1 Subset information flow control (FDP_IFC.1(HTTPS))......................................39
6.1.4.2 Simple security attributes (FDP_IFF.1(HTTPS))................................................39
6.1.4.3 Configuration value initialization (FMT_CFG.2(HTTPS))...................................40
6.1.4.4 Inter-TSF trusted channel (FTP_ITC.1).............................................................40
6.1.5 Identification, Authentication and Authorization........................................................41
6.1.5.1 Complete information flow control (FDP_IFC.2)................................................41
6.1.5.2 Simple security attributes (FDP_IFF.1(WSP))...................................................41
6.1.5.3 User attribute definition (FIA_ATD.1).................................................................42
6.1.5.4 Timing of authentication (FIA_UAU.1)...............................................................42
6.1.5.5 Timing of identification (FIA_UID.1)...................................................................43
6.1.5.6 User-subject binding (FIA_USB.1).....................................................................43
6.1.5.7 Configuration value initialization (FMT_CFG.2(WSP)).......................................43
6.1.5.8 Configuration of security functions (FMT_CFG.1)..............................................44
6.2 Security Functional Requirements Rationale.............................................................44
6.2.1 Coverage..................................................................................................................44
6.2.2 Sufficiency................................................................................................................45
6.2.3 Security requirements dependency analysis............................................................46
6.3 Security Assurance Requirements..............................................................................48
6.4 Security Assurance Requirements Rationale.............................................................49
7 TOE SUMMARY SPECIFICATION...................................................................................49
7.1 TOE Security Functionality..........................................................................................49
7.1.1 Cryptographic primitives...........................................................................................50
7.1.1.1 General characteristics of the TLS protocol.......................................................50
7.1.1.2 TLS implementation in the TOE.........................................................................50
7.1.2 Certificate Generation..............................................................................................51
7.1.3 Establishment and maintenance of TLS protected links...........................................51
7.1.4 Identification, authentication and authorization.........................................................52
7.1.4.1 HTTP session cookies.......................................................................................52
8 CONVENTIONS, TERMINOLOGY, AND ACRONYMS....................................................55
8.1 Terminology..................................................................................................................55
9 INDEX OF TABLES AND ILLUSTRATIONS....................................................................56
10 RELATED STANDARDS AND DOCUMENTS................................................................57
11 APPENDIX/APPENDICES...............................................................................................60
11.1 Appendix A: Overview of HOB RD VPN scenario.....................................................60
ii HOB GmbH & Co. KG
HOB RD VPN Software and Documentation 2005-2013 © HOB
All rights are reserved. Reproduction of editorial or pictorial contents without express permission is prohibited.
HOB RD VPN and HOBLink software and documentation have been tested and reviewed. Nevertheless, HOB will
not be liable for any loss or damage whatsoever arising from the use of any information or particulars in, or any
error or omission in, this document. HOB reserves the right to change the specification or parts of it without prior
notice.
iii HOB GmbH & Co. KG
Security Target for HOB RD VPN blue edition v 2.2____________________________4 of 62
Symbols and Conventions
This document uses certain symbols and conventions, which have the following meanings:
This symbol is used to indicate paragraphs with special informative character.
This symbol is used for procedures that may result in major changes. Please make
sure that the results will correspond with your intentions.
 References to HOB RD VPN/HOBLink program commands and dialog boxes are printed
in bold, e.g. Select the command Open…
 Keys or key combinations are put in square brackets, e.g. [space].
 Options and push buttons, selectable in a dialog box, are in printed bold, e.g. user
defined.
 Cross-references to other chapters or figures are printed in italics and are accompanied
by the symbol ►. The chapter and / or page number is also referenced.
 References to previous CC evaluations are printed in italics on a grey background, e.g.
interface 6.
Document history
Date Version Author Changes
Jan. 2014 2.2 Version to be published
Abbreviations and Acronyms
The following abbreviations and acronyms are used in this Security Target:
AES Advanced Encryption Standard
CA Certificate Authority
CBC Cipher Block Chaining
CC Common Criteria
CM Configuration Management
EAL Evaluation Assurance Level
FDP Forms of user Data Protection
GUI Graphical User Interface
HL HOBLink
HMAC Hash-based Message Authentication Code
HTTP Hypertext Transfer Protocol
HTTPS Hypertext Transfer Protocol / Secured
IP Internet Protocol
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Security Target for HOB RD VPN blue edition v 2.2____________________________5 of 62
JNI Java Native Interface
JRE Java Runtime Environment
JVM Java Virtual Machine
JWT Java Windows Terminal
LAN Local Area Network
MAC Message Authentication Code
MD Message Digest
OSP Operational Security Policy
PKI Public Key Infrastructure
PP Protection Profile
RDP Remote Desktop Protocol
RNG Random Number Generator
RSA Rivest, Shamir, Adleman
SAR Security Assurance Requirement
SFP Security Function Policy
SFR Security Functional Requirement
SHA Secure Hash Algorithm
SM HOB Security Manager
SSL Secure Socket Layer
ST Security Target
TCP Transmission Control Protocol
TLS Transport Layer Security
TOE Target Of Evaluation
TSF TOE Security Functions
TSP TOE Security Policy
TSS TOE Summary Specification
URL Uniform Resource Locator
WSG Web Secure Gate
WSP HOB WebSecureProxy
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Security Target for HOB RD VPN blue edition v 2.2____________________________6 of 62
Trademarks
 Linux is the registered trademark of Linus Torvalds in the U.S. and other countries.
 UNIX is a registered trademark of The Open Group1
.
 Microsoft Windows is a trademark of Microsoft Corporation.
 Oracle and Java are registered trademarks of Oracle and/or its affiliates.
 All other product names, company names and service names may be trademarks,
registered trademarks or service marks of their respective corporations or owners.
1
See http://www.unix.org/trademark.html
© 2005-2013 HOB GmbH & Co. KG. All rights reserved. 6
Security Target for HOB RD VPN blue edition v 2.2____________________________7 of 62
1 Introduction
1.1 Security Target and CC Identification
ST title Security Target for HOB RD VPN blue edition
ST version 2.2
Developer HOB GmbH & Co. KG, Cadolzburg, Germany
CC version Version 3.1, Revision 4
Certification ID BSI-DSZ-CC-0832
Assurance level EAL4, augmented by ALC_FLR.2
1.2 TOE Identification
TOE Reference
TOE / Product name HOB RD VPN blue edition
Product version 2.1 10.5397
1.3 TOE Type
The TOE is an encryption secured remote access solution (a so-called SSL-VPN) based on
the TLSv1.1 [RFC4346] and TLSv1.2 [RFC5246] protocol.
1.4 TOE Overview
HOB RD VPN blue edition is a software package that provides TLS secured access to
servers. In the evaluated configuration, it provides secured access to Remote Desktop
servers as well as to web servers. The evaluated configuration of the product is built of three
main components:
1. A gateway called “WebSecureProxy” located in front of the destination server
(referred to as “WSP”). This software includes a module called “HTTP handler” that
enables it to act as a web server gateway as well as an integrated web server. The
WSP can handle all incoming connections over one single TCP/IP port. The WSP is
equipped with a module called “HOBLink Secure, Server”2
that performs all
cryptographic operations on the server side.
2. A Java client application for Remote Desktop Services called “HOBLink JWT”.
HOBLink JWT is equipped with a module called “HOBLink Secure, Client”, that
performs all cryptographic operations on the client side. This component is located
on the server within the RD VPN server installation and is downloaded by the client
and executed on the client side.
3. An administrative tool called “HOBLink Security Manager” (Security Manager). It
generates the HOBLink Security Units (each a set of files) containing the
2
The identifiers “HOBLink Secure, Client” and “HOBLink Secure, Server” are formal definitions for a module called
“HOBLink Secure SSL Software module”. This module is referred to hereinafter as “HOBLink Secure, Client” or
“HOBLink Secure, Server” according to the role of the component it is used with. The “HOBLink Secure SSL
Software module” is executed in different ways on the server-side and on the client-side. It uses identical code
for cryptographic operations on both sides. The module is part of HOBLink Secure which is a software developed
by HOB.
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Security Target for HOB RD VPN blue edition v 2.2____________________________8 of 62
configurations and certificate(s) for the server and the client side. The HOB WSP
employs the HOBLink Security Unit for the server and HOBLink JWT uses that for
the client for establishing a secured communication. The administrator must transmit
the generated units to the WSP in a secure manner. The files of the client HOBLink
Security Unit are transmitted to the HOBLink JWT client via an already established
TLS channel. The client unit is therefore protected for integrity, authenticity and
privacy.
1.4.1 Required Hardware and Software
Table 1: Hardware and Software requirements
TOE component Hardware requirements Software requirements
HOBLink JWT
(client software):
Intel Pentium Processor 1 GHz
or CPU with equivalent or higher
processing speed
256 Mbytes of RAM available
MS Windows 7
MS Windows 8
Apple Mac OS X 10.8 Intel 64-bit
openSUSE Linux 12.2 (with graphical
subsystem installed)
WebSecureProxy
(gateway):
Intel Pentium Processor 1 GHz
or CPU with equivalent or higher
processing speed
1 Gbytes of RAM available
250 ... 450 Mbytes of non-
volatile storage space
SUSE Linux Enterprise Server 11 on
Intel EM64T SP2
HOBLink Security
Manager
(administration
workstation):
Intel Pentium Processor 1 GHz
or CPU with equivalent or higher
processing speed
256 Mbytes of RAM available
160 Mbytes of non-volatile
storage space
see “HOBLink JWT (client
software)” above
1.4.1.1 Java Virtual Machines
The TOE component HOBLink Security Manager implicitly installs a third party JVM on
Windows and Linux. The delivery of the JVM is mandatory on Linux and Windows, and this
JVM is not shared with any other software, so it can be considered to be outside of the TOE.
On Apple MAC OS X systems a Java Virtual Machine must already be installed before the
HOBLink Security Manager is installed. The installer software requires a JVM that is
downloaded from the Apple Mac OS X support web site. The following table contains the
JVM versions that are used for the HOBLink Security Manager.
Table 2: JVMs that are currently used for the HOBLink Security Manager
OS family JVM version
Windows Sun Java 1.6.0 update 26 (32-bit)
Apple Mac OS X Apple Java 1.6.0 update 65 (64-bit)
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Security Target for HOB RD VPN blue edition v 2.2____________________________9 of 62
OS family JVM version
Linux Sun Java 1.6.0 update 26 (32-bit)
The HOBLink JWT component is a Java application and executes within the client's JVM of
the installed JRE. The web browser starts the JVM (according to the configuration in the web
browser) and passes necessary information to start HOBLink JWT. Recommended versions
of web browsers are listed hereafter. HOBLink JWT runs on Java JVM versions listed in
table 3, but the client side user is advised to use the most up-to-date versions provided by
Oracle for security reasons.
Table 3: JVMs allowed to be used with HOBLink JWT
OS family JVM version3
Windows Oracle Java 1.7.0 update 45 (32-bit)
Apple Mac OS X Oracle Java 1.7.0 update 45 (64-bit)
Linux Oracle Java 1.7.0 update 45 (32-bit)
Note: The WebSecureProxy is not a Java software and does therefore not require a JVM.
1.4.1.2 Browsers
Web browsers with the support for TLS v1.1 and TLS v1.2 are suitable for communication
with the HTTP handler module. Browsers that currently support this requirement are, for
example, Internet Explorer, Opera or Google Chrome.
1.4.1.3 LDAP
The “WebSecureProxy” (WSP) uses an LDAP server to verify credentials and read other
information as discussed in the subsequent sections.
WSP does not require a specific brand of LDAP server, but the LDAP server must support
LDAPv34
.
1.4.2 Intended Method of Use
Users of the TOE start a browser on their client system and connect to the
“WebSecureProxy” (WSP) server using the HTTPS protocol. The WSP server requests a
username and password from the client that are verified with the user's credentials stored in
an LDAP server. After a successful identification and authentication against an LDAP server,
the user is granted access to Remote Desktop services (using the HOBLink JWT which is
executed within a JVM) as well as web-based services (displayed by the client browser)
protected by the TOE. Access to the Remote Desktop services or web-based services is
granted by the WSP based on an access configuration applicable to the authenticated user.
The WSP implements a forwarding of the RDP data (messages) between the HOBLink JWT
client and the protected Remote Desktop services.
3
Java JRE 1.7 implicitly supports TLS v1.1 and TLS v1.2. The user must ensure that these TLS protocols are
activated in the Java Control Panel.
4
An implementation of parts of RFC 4510 and related documents is required for the performed LDAP database
accesses.
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Security Target for HOB RD VPN blue edition v 2.2___________________________10 of 62
To ensure a seamless access of web pages from the protected web-based services, the
WSP implements an address-rewrite of the transmitted URLs as well as of the URLs found in
the web pages to point to the WSP as gateway.
In the evaluated configuration, the communication is routed between the WSP and either the
client browser or the HOBLink JWT through an untrusted network. All of these
communications are secured using the TLS protocol when in transit through the untrusted
network – the communication between WSP and the client's browser or HOBLink JWT is
always routed through a TLS channel.
1.4.3 Major Security Features
The evaluated configuration of HOB RD VPN blue edition provides the following security
services that are considered in this document:
• The TOE provides cryptographic primitives required to implement the TLS protocol,
including symmetric and asymmetric key generation methods.
• The “Certificate Generation” service is provided by a utility for the generation of
certificates and keys for use in TLS secured connections. This software is called
“HOBLink Security Manager”.
• The “TLS Protocol Function” is provided by the module “HOBLink Secure SSL
Software module”. The HOBLink Secure SSL module implements the cryptographic
primitives as well as the TLS protocol logic. Therefore, this module encrypts the
HTTP or RDP data using the TLS protocol before sending it to the recipient via the
untrusted network. In addition, this module also decrypts the received TLS data
stream. The HOBLink Secure SSL Software module is used by HOBLink JWT as
well as by the WSP. To distinguish both occurrences of this module, this Security
Target uses the terms of “HOBLink Secure, Client” for the instance integrated with
HOBLink JWT and “HOBLink Secure, Server” for the instance integrated with WSP.
• The WSP requires the user to identify and authenticate before proceeding with any
access request to a server. The WSP denies access to the protected resources
without a successful identification and authentication. The WSP allows the
administrator to specify role-based access lists. These access lists reference the
protected HTTP or RDP servers a user is allowed or denied to connect to.
1.5 TOE Description
This section provides a product description in order to point out the purpose of the TOE and
its possible fields of application. Furthermore, the scope of the evaluated configuration is
defined.
1.5.1 Product operation
HOB RD VPN blue edition is a software package that provides TLS secured access to web
servers and Remote Desktop servers. These servers are the resources protected by the
TOE.
The evaluated configuration of the product is built of the following main components that
work together to deliver the communication protection.
The following figure visualizes the systems and components involved, the physical boundary
of the TOE, and shows relevant communication paths. The following sections explain the
different TOE components. As the illustration may be hard to read, it is presented in a larger
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Security Target for HOB RD VPN blue edition v 2.2___________________________11 of 62
scale in section 11.1.
Fig. 1: Overview of HOB RD VPN scenario
1.5.1.1 WSP
The WSP reads its configuration and the server HOBLink Security Unit during start up. The
data of each file of the server HOBLink Security Unit are passed to “HOBLink Secure,
Server”. The WSP accepts incoming encrypted requests, ensures the identification and
authentication of the user via username and password and generates a start web page with
URLs (so-called links) to the web servers and Remote Desktop servers the user is allowed to
access.
The username and password are validated with an LDAP server.
The start web page is dynamically created for each user based on the master copy web page
stored in a folder of the HOB RD VPN installation and according to the settings found in the
WSP configuration and the Web Server Gate (WSG) configuration. These Web Server Gate
settings are stored in LDAP for this user.
The list of servers authorized for use by the user are specified in the WSP configuration file.
There is a list for each of the web servers and the Remote Desktop servers. The list for the
Remote Desktop servers works as a so-called white list, while the list for the web servers can
work as a white list or as a black list. The WSP configuration can contain these lists with a
global part and a role-based part. Authorization for the access of the users to allowed servers
depends on the role assigned to the users.
When a user connects to the WSP, the WSP generates an HTTP session cookie after a
successful authentication and returns it to the calling browser. This cookie must be presented
by the user browser for each HTTP request. In addition, when establishing an RDP session
© 2004-2013 HOB GmbH & Co. KG. All rights reserved. 11
Remote Desktop Server
Web Secure Proxy
Gateway
Server
HL Secure, Server
Client
Computer
System
Web Server
Server Security Unit
Client Security Unit
HL JWT
package
Web Browser
HOBLink JWT
HL Secure, Client
WSP configuration tool
LDAP
database
LDAP
Server
HL Security Manager
Administrative
Workstation
HL Secure, Client
HTTP Handler
JAVA runtime environment
client configuration
tool for LDAP-based
user administration
Security Target for HOB RD VPN blue edition v 2.2___________________________12 of 62
HOBLink JWT must transmit the ticket information of the cookie to the WSP to allow the
WSP assign the new connection to the already authenticated user. Note: even if a user
knows other URLs to protected servers (either web or Remote Desktop servers) that are
located in the "in-house" area and are not listed on the user's start web page, the WSP does
not allow access to this server if the WSP configuration excludes this user from the group of
authorized users or does not include the user in this group.
The WSP mediates access to:
• the WSP-integrated web server (part of the TOE), by accepting the HTTPS requests.
The integrated web server (which is a module of the “HTTP handler”) of the WSP
involved in this operation ensures that the user credentials are passed to the
authentication method and that a unique cookie for each HTTP session is created
and assigned to a user.
• a protected web server by unwrapping the HTTP requests from the received TLS
requests. The WSP establishes an unencrypted connection to the destination server
system. The processing of the TLS protocol enforced for data in transit between the
WSP and the client web browser is performed by “HOBLink Secure, Server”.
Destination servers are only available to users if they are previously defined in the
WSP configuration. Additionally, the Web Server Gate configuration of a specific
user that is read from LDAP defines the start web page for this user. The WSP
ensures that any link on the back-end web site is rerouted through the WSP.
• a protected RDP server by unwrapping the RDP requests from the received TLS
requests. The WSP establishes an unencrypted connection to the destination server
system. The processing of the TLS protocol enforced for data in transit between the
WSP and HOBLink JWT is performed by “HOBLink Secure, Server”. Destination
servers are only available to users if they are previously defined in the WSP
configuration. Additionally, the Web Server Gate configuration of a specific user that
is read from LDAP defines the start web page for this user.
• the JWT configuration of a specific user read from LDAP. This configuration
determines the window GUI and user specific properties such as the keyboard
features or language for the RDP session and the peripheral components that are
available from within the RDP session. Note: the WSP only allows the establishment
of a new RDP communication link using the ticket information of the above
mentioned HTTP cookie that HOBLink JWT must present to the WSP.
A start web page is dynamically created for each user displaying the links to the authorized
servers based on the access control list applicable to the user. In addition, the layout
parameter settings for the link page are found in the Web Server Gate configuration stored in
LDAP for this user.
1.5.1.2 Client-side
The user starts a browser on the client system, provides the destination URL and initiates a
connection to the WSP. The user must establish trust in the server certificate offered by the
WSP it connects to, but which is outside this evaluation. This can be established by loading
the WSP root certificate onto the client system (e.g. into the browser or the operating system
key store) to allow the browser to validate the certificate offered by the WSP. A similar
approach must be claimed for the JRE.
After connecting to the WSP, the user has to identify and authenticate via a username and
password. The user credentials are matched with the credentials stored in an LDAP server.
The WSP performs an LDAP-bind operation to verify the credentials, which implies that the
identification and authentication decision is performed by the LDAP server and the WSP
enforces the decision made by the LDAP server.
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Security Target for HOB RD VPN blue edition v 2.2___________________________13 of 62
The WSP-integrated web server provides a web page together with a unique cookie after a
successful authentication. This page contains the URLs to protected web servers as well as
links to those protected Remote Desktop servers the user is authorized to access.
The currently established HTTPS session with its cookie continues to be used when
accessing protected web servers.
When accessing a Remote Desktop server, the selected URL causes the Java application of
“HOBLink JWT” to be downloaded. HOBLink JWT is stored as the HL JWT package in a
folder of the RD VPN installation. The package contains the Java jar-file and additional JNI
executables that are used to provide native, OS-dependent functions to the Java application.
HOBLink JWT is executed as a Java Webstart application on the client system.
1.5.1.2.1 JWT connection
As mentioned above, HOBLink JWT is downloaded by selecting a link to a Remote Desktop
server on the start web page presented by the WSP. Selecting such a link triggers the
browser to start a HTTPS secured connection to the destination address and downloads the
HOBLink JWT Webstart file. The HTTP session cookie is used to authenticate the
connections with the WSP to allow the WSP to assign the new connection to the already
authenticated user. The HOBLink JWT Webstart file as provided by the link on the WSP-
generated web start page contains the destination address, the HTTP session cookie, the
client HOBLink Security Unit and a unique identification for the user's JWT configuration that
will be downloaded from the server component of RDVPN. The client HOBLink Security Unit
is stored in a folder of the HOB RD VPN installation (on the server) and is defined in the
WSP configuration. In addition, the HOBLink JWT Webstart file points to the HOBLink JWT
package (symbolized as “HL JWT package” in figure ► Fig. 1: Overview of HOB RD VPN
scenario) that is to be downloaded by the JVM and that implements the client-side logic
ensuring a secured data tunneling for RDP.
After the download of the HOBLink JWT package and its startup, HOBLink JWT establishes
a new connection to the WSP and the “HOBLink Secure, Client” module initiates a new TLS
handshake to “HOBLink Secure, Server” within the WSP.
All subsequent data exchanges are tunneled through this new TLS secured connection.
During the establishment of the TLS link, the “HOBLink Secure, Client” module performs a
server certificate validation using the root certificate or certificate chain found in the client
HOBLink Security Unit already obtained.
To allow the WSP to assign the newly instantiated TLS connection to the already
authenticated user, HOBLink JWT passes the information of the obtained HTTP session
cookie5
to the WSP. The WSP now uses this information for user authentication and after a
successful verification the connection is continued or terminated if not successful. The WSP
transfers data between HOBLink JWT on the client side through the newly established TLS
channel and the selected Remote Desktop server in the protected environment.
After the successful establishment of the TLS link, a new window is presented that allows the
user to enter the credentials needed to access the requested Remote Desktop server. These
credentials are forwarded to the Remote Desktop server with the intention of allowing this
server to perform the identification and authentication of the user based on these credentials.
HOBLink JWT now uses the RDP protocol communication for the Remote Desktop session
tunneled through the established TLS tunnel and displays the corresponding remote desktop
GUI.
5
Please note that the session ticket, the user name and the domain name that are embedded in the HTTP
session cookie are used for the mentioned authentication process.
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1.5.1.2.2 Web Server Gate operation of HTTP handler
The user clicks on a link to a protected web server on the start page offered by the WSP.
The WSP establishes the communication with the protected web server and forwards the
HTTP requests from the client web browser to the web server. The replies of the web server
are also forwarded to the client web browser using the HTTPS communication channel that is
already established with the initial HTTPS request of the client browser.
The user HTTP session cookie is used to authenticate the requests in the WSP. All HTTP
requests and links within HTML pages are modified by the Web Server Gate within the WSP
to reroute these addresses from the browser to the Web Server Gate and from there via
WSP to the web server and back.
1.5.1.3 HOBLink Security Manager
The administrative tool “HOBLink Security Manager” (Security Manager) is used to generate
the HOBLink Security Units. A HOBLink Security Unit is a set of files containing the
configurations and certificates for the server and the client sides.
The HOBLink Security Manager implements the mechanism to generate asymmetric keys to
support the TLS protocol.
The HOBLink Security Manager includes the HOBLink Secure SSL Software module and
uses the certificate generation, the random number generator and other functions. It can be
seen that the HOBLink Security Manager does not explicitly use the functionality for server or
client as needed by the components involved in the secured communication. The HOBLink
Secure SSL Software module that it uses includes only those same classes as used in
HOBLink JWT. Therefore "HL Secure, Client" is added to the HOBLink Security Manager in
figure ► Fig. 1: Overview of HOB RD VPN scenario. The HOBLink Security Manager itself
does not require server specific or client specific functions.
1.5.2 TOE boundaries
Figure ► Fig. 1: Overview of HOB RD VPN scenario shows the physical and logical
boundaries of the TOE. The following table provides a short description of the software
components for the evaluation.
1.5.2.1 Physical
The following software components form the TOE:
Table 4: Software components of the TOE
Component Purpose
WebSecureProxy A multi-functional gateway that translates the encrypted data stream
from the public side of the network into “clear-text” communication
for the internal LAN and vice versa.
The cryptographic operations are performed by the module
“HOBLink Secure, Server”.
The module “HTTP Handler” contains the functions “Web Server
Gate” and “integrated web server” that provide additional web server
gateway and web server functionality.
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Component Purpose
HOBLink Security
Manager
An offline PKI utility designed to create, import, export and maintain
X.509v3 certificates and TLS configurations required for the TLS
and HTTPS connections.
HOBLink JWT A Java application for Remote Desktop Services. Its purpose is to
show the GUI of a session to a Remote Desktop server on the local
workstation.
It includes a module called “HOBLink Secure, Client” that performs
the cryptographic operations.
The HOB RD VPN blue edition product media contains additional software that can be used
with the WSP or in the environment the WSP is used. This additional software allows, for
example, alternative protocols or alternative authentication methods to be used. All the
additional software is not part of the TOE and does not provide security services relevant to
the context of this document.
Along with the TOE components mentioned above, HOB provides a number of tools that
fulfill the requirements to create and edit specific HOB RD VPN blue edition configurations.
This includes the configurations for TOE relevant components and also the configurations for
the additional software on the product media. The manual also provides information to
analyze most configuration files, if the files are human readable.
The configuration tools and software used to view or edit configuration files does not belong
to the TOE and therefore will not be discussed further.
The following guidance is delivered together with the TOE:
• Administration Guide HOBLink Secure and HOBLink Security Manager
• Administration Guide HOB Remote Desktop VPN blue edition
1.5.2.2 Logical
The primary security features of the TOE are:
• Cryptographic primitives required to implement the TLS protocol, including symmetric
and asymmetric key generation methods. To support the cryptographic primitives, a
deterministic random number generator is provided which is based on the
CTR_DRBG design with an AES-128 core specified in the NIST SP800-90A
documentation.
• RSA certificate and RSA key generation provided by the HOBLink Security Manager
to support the TLS protocol handshake.
• Establishment and maintenance of TLS protected links. These links can transport
HTTP requests as well as the RDP protocol. The TLS protocol implementation
provided by the web browser and by the JVM in the JRE is not part of the TOE
however it is enforced by the TOE component of the WSP.
• Enforcement of the identification and authentication decisions performed by the
LDAP server before users can access any resources protected by the TOE. In
addition, the TOE implements a role-based access control. Each user can be given
or denied access to a protected resource of:
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◦ web servers,
◦ Remote Desktop servers.
• Mechanisms to configure the security functions are offered by the TOE.
The TOE provides many more functions and mechanisms. The evaluation ensures that all
these additional functions do not interfere with the above mentioned security mechanisms in
the evaluated configuration of the TOE. Mechanisms and functions that would interfere with
the operation of the security functions are disallowed in the evaluated configuration. The
section of the administrator guidance discussing the specific configuration of the product to
conform to the Common Criteria evaluation provides instructions to the administrator on how
to disable them. Note: TOE mechanisms which provide additional restrictions to the above
claimed security functions are allowed in the TOE's evaluated configuration.
The WSP and HOBLink JWT are administered by configuration files which constitute the
management interface. The Security Manager is a utility to generate among others
configuration files i.e. the HOBLink Security Units for the Server and Client. It does not
enforce any form of roles.
Note: Software and mechanisms not covered with security claims and subsequent
assessments during the evaluation or disabling of the respective functionality in the evaluated
configuration result from resource constraints during the evaluation, but does not imply that
the respective package or functionality is implemented insecurely.
1.5.2.3 Configurations
Before any TLS connections can be established, the administrator must generate the
configuration for the “WebSecureProxy” server. The guidance documents the contents of the
configuration file.
In addition, before any TLS connection can be established, the administrator creates two
HOBLink Security Units, one for the “HOBLink Secure, Client” and one for the “HOBLink
Secure, Server”. Each “HOBLink Security Unit” is a set of files and consists of the following
three files:
• the configuration file,
• the certificate database file,
• and the password file holding the password that protects access to the configuration
file and to the certificate database file.
Both HOBLink Security Units are manually and securely distributed to the WSP by means
outside the TOE. The guidance documents the directory structure which hosts the files for
the server and client side. When the client requests the initiation of a Remote Desktop
session, the client downloads the HOBLink JWT Java application and the client HOBLink
Security Unit via the already established HTTPS channel.
Furthermore, a configuration file for the client software “HOBLink JWT” has to be created.
This configuration file mainly defines a set of presentation parameters such as the display
size. The configuration parameters specified in this configuration file are not relevant to the
enforcement of the security claims made in this Security Target. The administrator stores the
configuration information in the LDAP tree, either on a per-user basis or on a per-group
basis.
All configuration files are generated and maintained with tools that are not part of this TOE.
All configuration parameters that are intended to be used in the configuration files are
documented in the manual.
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During the initial installation, an OpenDJ LDAP server is additionally installed on the server
system. An administrative tool exists that allows the configuration of the HOB WSP with GUI
support if a manually edited and reviewed configuration is not to be used. The OpenDJ LDAP
system and the configuration GUI tool are not part of the TOE. Therefore, the LDAP server is
unused in the evaluated configuration except in the case of a severe configuration error.
2 CC Conformance Claim
This ST is CC Part 2 extended and CC Part 3 conformant, with a claimed Evaluation
Assurance Level of EAL4, augmented by ALC_FLR.2.
This ST does not claim conformance to any Protection Profile:
Common Criteria [CC] version 3.1 revision 4 is the basis for this conformance claim.
3 Security Problem Definition
In order to clarify the nature of the security problem that the TOE is intended to solve, this
section describes the following:
• Any known or assumed threats to the assets against which protection within the TOE
or its environment is required.
• Any organisational security policy statements or rules with which the TOE must
comply.
• Any assumptions about the security aspects of the environment and/or of the manner
for which the TOE is intended.
3.1 Threat Environment
Threats to be countered by the TOE are characterized by the combination of an asset being
subject to a threat, a threat agent and an adverse action.
3.1.1 Assets
The assets in transit to be protected are TSF and user data transmitted between physically
separated parts of the TOE over an untrusted network.
The resource assets to be protected are the web servers and RDP servers the WSP
mediates access to.
3.1.2 Threat Agents
The threat agents are attackers who have access to the untrusted network and who have the
ability and skill to monitor, modify, delete, re-play or re-order transmitted information or to
insert information into the transmitted information. Attackers are assumed to have an
enhanced-basic attack potential.
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3.1.3 Threats countered by the TOE
Table 5: Threats to be countered by the TOE
Threat Description
T.Access.Resource A threat agent might gain access to the resources of web
servers and Remote Desktop servers protected by the WSP
without being appropriately authorized according to the TOE
security policy.
T.IA.Masquerade A threat agent might masquerade as an authorized entity
including the TOE itself or a part of the TOE in order to gain
unauthorized access to resources of web servers and
Remote Desktop servers protected by the WSP.
T.IA.User A threat agent might gain access to resources of web servers
and Remote Desktop servers protected by the WSP without
being identified and authenticated.
T.Untrusted-Path A threat agent may attempt to disclose, modify, delete, re-
play, re-order or insert TSF and/or user data by monitoring,
modifying, deleting, re-playing or re-ordering the information
transmitted over the untrusted network or by inserting
additional information in the transmitted information in an
unnoticeable manner.
3.1.4 Threats countered by the TOE environment
There are no threats to be solely addressed by the operational environment.
3.2 Assumptions
3.2.1 Environment of use of the TOE
3.2.1.1 Physical
Table 6: Assumptions to be covered by physical constraints
Assumption Description
A.Physical It is assumed that the environment provides the TOE with
appropriate physical security, commensurate with the value
of the IT assets protected by the TOE.
3.2.1.2 Personnel
Table 7: Assumptions to be covered by personnel constraints
Assumption Description
A.Administrators The TOE environment is managed by one or more
competent individuals. The system administrative personnel
are not careless, willfully negligent, or hostile, and will follow
and abide by the instructions provided by the guidance
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Assumption Description
documentation.
A.AuthUser Authorized users possess the necessary authorization to
access at least some of the resources protected by the TOE
and are expected to act in a cooperating manner in a benign
environment.
A.TrainedUser Users are sufficiently trained to use the TOE in a secure
manner.
3.2.1.3 Procedural
Table 8: Assumptions to be covered by procedural constraints
Assumption Description
A.DestroyRSA RSA keys stored in non-volatile storage are securely
destroyed when they are no longer needed.
A.LDAPMgt The LDAP server is assumed to be under the same
management control, operating under the same security
policy constraints and having the same level of physical
protection as the TOE.
A.LDAPFunc The LDAP server is assumed to correctly implement the
functionality required by the TSF consistent with the
assumptions defined for this functionality, i.e.:
• correctly perform the I&A decision requested via an
LDAP-bind operation by the TOE (WSP),
• protect the user credentials against brute force
attacks6
,
• supporting LDAPv3 protocol for accessing the
directory services.
A.Systems The operating systems, the Java virtual machines, and the
web browser operate according to their specification. These
external systems are configured in accordance with the
installation guidance and the evaluated configuration
guidance of the TOE. These systems are assumed to be well
managed and trustworthy.
A.Time The underlying operating system provides reliable time
information to the TOE.
3.2.1.4 Connectivity
Table 9: Assumptions to be covered by connectivity constraints
Assumption Description
A.ProtectedResources Any connection between the untrusted network and the
protected resources of web servers and Remote Desktop
6
Techniques such as login authentication delay, account lockout after consecutive unsuccessful login attempts,
password complexity rules, etc. can be used to implement this requirement.
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Assumption Description
servers is established via the WSP by an appropriate
network architecture.
A.SecMgr The Security Manager is installed on a separate machine that
is not physically connected to any network and the HOBLink
Security Units generated by this tool are transferred securely
to the WSP.
A.WSP The WebSecureProxy is installed on a separate machine
without unprivileged users having local access and that does
not host any productive relevant services such as database
servers or alternative web servers besides the software that
is provided through the HOB product installation. The logical
access to this machine is restricted to authorized
administrators.
3.3 Organizational Security Policies
Table 10: Organizational Security Policies to be met by the TOE
Assumption Description
P.Certificates The RSA keys and certificates are generated by the TOE
facilities.
4 Security Objectives
This section identifies the security objectives for the TOE and for the TOE environment.
4.1 Objectives for the TOE
Table 11: Security Objectives for the TOE
Objective Description
O.Certificates The TOE provides the facility to generate RSA certificates
and the corresponding keys.
O.Crypto.Net The TSF must be designed and implemented in a manner
that allows for establishing a trusted channel between
distributed parts of the TOE that protects the user data and
TSF data transferred over this channel from disclosure and
undetected modification and prevents masquerading of the
remote trusted IT system.
O.I&A The TOE must ensure that users have been successfully
authenticated before allowing any action the TOE has
defined to provide to authenticated users only.
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Objective Description
O.Resource.Access The TSF must control access of subjects and/or users to the
resources of web servers and Remote Desktop servers
based on identity of the user. The TSF must provide
authorized users with the means to specify which
users/subjects are allowed to access a specific named object
in that access mode.
4.2 Objectives for the Operational Environment
Table 12: Security Objectives for the TOE environment
Objective Description
OE.Administrators Those responsible for the TOE environment are competent
and trustworthy individuals, capable of managing the TOE
and the security of the information it contains. The system
administrative personnel are not careless, willfully negligent,
or hostile, and will follow and abide by the instructions
provided by the guidance documentation.
OE.LDAP The LDAP server must implement the functionality required
by the TSF correctly and provides its result to the TOE
supporting LDAPv3. In particular the LDAP server must
correctly perform the I&A decision supported by the
protection against brute forcing account credentials
requested via an LDAP-bind operation by the TOE (WSP).
The LDAP server must be under the same management
control, operating under the same security policy constraints
and must have the same level of physical protection as the
TOE.
OE.InfoProtect Those responsible for the TOE must establish and
implement procedures to ensure that information is protected
in an appropriate manner. In particular:
• Users are authorized to access parts of the data
managed by the TOE and are trained to use the TOE
in a secure manner in a benign environment.
• Any connection between the untrusted network and
the protected resources of web servers and Remote
Desktop servers must be established via the WSP by
an appropriate network architecture.
OE.Install Those responsible for the TOE must establish and
implement procedures to ensure that the hardware, software
and firmware components that comprise the system are
distributed, installed and configured in a secure manner
supporting the security mechanisms provided by the TOE.
OE.WSP Those responsible for the TOE, install the WebSecureProxy
on a separate machine without unprivileged users having
local access and that does not host any productive relevant
services such as database servers or alternative web servers
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Objective Description
besides the software that is provided through the HOB
product installation. The logical access to this machine is
restricted to authorized administrators.
OE.Physical Those responsible for the TOE must ensure that those parts
of the TOE critical to enforcement of the security policy are
protected from physical attack that might compromise IT
security objectives. The protection must be commensurate
with the value of the IT assets protected by the TOE.
OE.DestroyRSA Those responsible for the TOE must assure that RSA keys
maintained with the HOBLink Security Units are securely
destroyed when they are no longer needed.
OE.SecMgr Those responsible for the TOE must assure that the Security
Manager is installed on a separate machine that is not
physically connected to any network and that the HOBLink
Security Units generated by this tool are transferred securely
to the WSP.
OE.System Those responsible for the TOE must ensure that the
operating systems, the Java virtual machines, and the web
browser are installed and configured in accordance with the
guidance of the TOE and that these mechanisms operate as
specified. These systems are well managed and trustworthy.
This also covers that only the software enumerated in this ST
are used as underlying platform to ensure that proper date
and time information is available.
4.3 Security Objectives Rationale
4.3.1 Coverage
The following table provides a mapping of TOE objectives to threats and policies, showing
that each objective counters or enforces at least one threat or policy, respectively.
Table 13: Mapping of security objectives to threats and policies
Objective Threats / OSPs
O.Certificates P.Certificates
O.Crypto.Net T.Untrusted-Path
O.I&A T.IA.Masquerade, T.IA.User
O.Resource.Access T.Access.Resource
The following table provides a mapping of the objectives for the Operational Environment to
assumptions, threats and policies, showing that each objective holds, counters or enforces at
least one assumption, threat or policy, respectively.
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Table 14: Mapping of security objectives for the Operational Environment to assumptions, threats and
policies
Objective Assumptions / Threats / OSPs
OE.Administrators A.Administrators
OE.LDAP A.LDAPMgt, A.LDAPFunc, T.IA.User, T.IA.Masquerade
OE.InfoProtect A.AuthUser, A.TrainedUser, A.ProtectedResources
OE.Install A.Administrators
OE.WSP A.WSP
OE.Physical A.Physical
OE.DestroyRSA A.DestroyRSA
OE.SecMgr A.SecMgr
OE.System A.Systems, A.Time
4.3.2 Sufficiency
The following rationale provides justification that the security objectives are suitable to
counter each individual threat and that each security objective tracing back to a threat, when
achieved, actually contributes to the removal, diminishing or mitigation of that threat:
Table 15: Sufficiency of objectives countering threats
Threat Rationale for security objectives
T.Access.Resource The threat of accessing the resources of web servers and
Remote Desktop servers protected by the WSP without
being appropriately authorized according to the TOE security
policy is removed by:
• O.Resource.Access requiring the TSF to control
access of subjects and/or users to the resources of
web servers and Remote Desktop servers based on
identity of the user. The TSF must provide authorized
users with the means to specify which users/subjects
are allowed to access a specific named object in that
access mode.
T.IA.Masquerade The threat of masquerading as an authorized entity including
the TOE itself or a part of the TOE in order to gain
unauthorized access to resources of web servers and
Remote Desktop servers protected by the WSP is removed
by:
• O.I&A requiring the TOE to ensure that users have
been successfully authenticated before allowing any
action the TOE has defined to provide to
authenticated users only.
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Threat Rationale for security objectives
• OE.LDAP requiring that the LDAP server correctly
performs the requested I&A decision, operating
under the same security policy constraints as the
TOE, having the same level of physical protection as
the TOE and requiring the same management
control as for the TOE.
T.IA.User The threat of gaining access to resources of web servers and
Remote Desktop servers protected by the WSP without
being identified and authenticated is removed by:
• O.I&A requiring the TOE to ensure that users have
been successfully authenticated before allowing any
action the TOE has defined to provide to
authenticated users only.
• OE.LDAP requiring that the LDAP server correctly
performs the requested I&A decision, operating
under the same security policy constraints as the
TOE, having the same level of physical protection as
the TOE and requiring the same management
control as for the TOE.
T.Untrusted-Path The threat of attempting to disclose, modify, delete, re-play,
re-order or insert user data by monitoring, modifying,
deleting, re-playing or re-ordering the information transmitted
over the untrusted network or by inserting additional
information in the transmitted information in an unnoticeable
manner is removed by:
• O.Crypto.Net requiring the TSF to be designed and
implemented in a manner that allows for establishing
a trusted channel between distributed parts of the
TOE that protects the user data and TSF data
transferred over this channel from disclosure and
undetected modification and prevents masquerading
of the remote trusted IT system.
The following rationale provides justification that the security objectives for the environment
are suitable to cover each individual assumption, that each security objective for the
environment that traces back to an assumption about the environment of use of the TOE,
when achieved, actually contributes to the environment achieving consistency with the
assumption, and that if all security objectives for the environment that trace back to an
assumption are achieved, the intended usage is supported:
Table 16: Sufficiency of objectives holding assumptions
Assumption Rationale for security objectives
A.Physical The assumption that the environment provides the TOE with
appropriate physical security, commensurate with the value
of the IT assets protected by the TOE is covered by:
• OE.Physical requiring that those responsible for the
TOE must ensure that those parts of the TOE critical
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Assumption Rationale for security objectives
to enforcement of the security policy are protected
from physical attack that might compromise IT
security objectives. The protection must be
commensurate with the value of the IT assets
protected by the TOE.
A.Administrators The assumption that the TOE environment is managed by
one or more competent individuals. The system
administrative personnel are not careless, willfully negligent,
or hostile, and will follow and abide by the instructions
provided by the guidance documentation is covered by:
• OE.Administrators requiring that those responsible
for the TOE environment are competent and
trustworthy individuals, capable of managing the
TOE and the security of the information it contains.
The system administrative personnel are not
careless, willfully negligent, or hostile, and will follow
and abide by the instructions provided by the
guidance documentation.
• OE.Install requiring that those responsible for the
TOE must establish and implement procedures to
ensure that the hardware, software and firmware
components that comprise the system are
distributed, installed and configured in a secure
manner supporting the security mechanisms
provided by the TOE.
A.AuthUser The assumption that authorized users possess the necessary
authorization to access at least some of the resources
protected by the TOE and are expected to act in a
cooperating manner in a benign environment is covered by:
• OE.InfoProtect requiring that users are authorized to
access parts of the data managed by the TOE.
A.TrainedUser The assumption that users are sufficiently trained to use the
TOE in a secure manner is covered by:
• OE.InfoProtect requiring that users are trained to use
the TOE in a secure manner.
A.DestroyRSA The assumption that RSA keys stored in non-volatile storage
are securely destroyed when they are no longer needed is
covered by:
• OE.DestroyRSA requiring that those responsible for
the TOE must assure that RSA keys maintained with
the HOBLink Security Units are securely destroyed
when they are no longer needed.
A.LDAPMgt The assumption that the LDAP server is under the same
management control, operating under the same security
policy constraints and having the same level of physical
protection as the TOE. is covered by:
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Assumption Rationale for security objectives
• OE.LDAP requiring the LDAP server to be under the
same management control, operating under the
same security policy constraints and having the
same level of physical protection as the TOE.
A.LDAPFunc The assumption that the LDAP server correctly implements
the functionality required by the TSF and provide it to the
TOE consistent with the assumptions defined for this
functionality, i.e.:
• correctly perform the I&A decision requested via an
LDAP-bind operation by the TOE (WSP),
• protect the user credentials against brute force
attacks,
• supporting LDAPv3 protocol for accessing the
directory services.
is covered by:
• OE.LDAP requiring that the LDAP server correctly
performs the I&A decision supported by the
protection against brute forcing account credentials
requested via an LDAP-bind operation by the TOE
(WSP) supporting LDAPv3.
A.Systems The assumption that the operating systems, the Java virtual
machines, and the web browser operate according to their
specification. These external systems are configured in
accordance with the installation guidance and the evaluated
configuration guidance of the TOE and are assumed to be
well managed and trustworthy is covered by:
• OE.System requiring that those responsible for the
TOE must ensure that the operating systems, the
Java virtual machines, and the web browser are
installed and configured in accordance with the
guidance of the TOE and that these mechanisms
operate as specified and are well managed and
trustworthy.
A.Time The assumption that the underlying operating system
provides reliable time information to the TOE is covered by:
• OE.System requiring that only the software
enumerated in this ST are used as underlying
platform to ensure that proper date and time
information is available.
A.ProtectedResources The assumption that any connection between the untrusted
network and the protected resources of web servers and
Remote Desktop servers is established via the WSP by an
appropriate network architecture is implemented by:
• OE.InfoProtect requiring that any connection
between the untrusted network and the protected
resources of web servers and Remote Desktop
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Assumption Rationale for security objectives
servers must be established via the WSP by an
appropriate network architecure.
A.SecMgr The assumption that the Security Manager is installed on a
separate machine that is not physically connected to any
network and the HOBLink Security Units generated by this
tool are transferred securely to the WSP is covered by:
• OE.SecMgr requiring that those responsible for the
TOE must assure that the Security Manager is
installed on a separate machine that is not physically
connected to any network and that the HOBLink
Security Units generated by this tool are transferred
securely to the WSP.
A.WSP The assumption that the WebSecureProxy is installed on a
separate machine without unprivileged users having local
access to the machine and that does not host any productive
relevant services such as database servers or alternative
web servers besides the software that is provided through
the HOB product installation is covered by:
• OE.WSP requiring that those responsible for the
TOE install the WebSecureProxy on a separate
machine without unprivileged users having local
access and that does not host any productive
relevant services such as database servers or
alternative web servers besides the software that is
provided through the HOB product installation. The
logical access to this machine is restricted to
authorized administrators.
The following rationale provides justification that the security objectives are suitable to cover
each individual organizational security policy, that each security objective that traces back to
an OSP, when achieved, actually contributes to the implementation of the OSP, and that if all
security objectives that trace back to an OSP are achieved, the OSP is implemented:
Table 17: Sufficiency of objectives enforcing Organizational Security Policies
OSP Rationale for security objectives
P.Certificates The policy that the RSA keys and certificates are generated
by the TOE facilities is implemented by:
• O.Certificates requiring the TOE to provide the
facility to generate RSA certificates and the
corresponding keys.
5 Extended Components Definition
The ST claims the following extended components:
• FCS_RNG.1
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• FMT_CFG.1
• FMT_CFG.2
The SFR FCS_RNG.1 is derived from [KS2011].
The TOE does not support administrative roles in the evaluated configuration, as this is
handled in the TOE environment. The TOE is managed by configuration files. To better
model this, the family CFG is introduced in class FMT instead of using
FMT_MSA/FMT_SMF.
5.1 Class FMT: Security management
5.1.1 TOE Configuration (FMT_CFG)
Family behavior
This family defines requirements for TOE configurations that are independent of
administrative roles.
Component leveling
FMT_CFG.1 specifies configurability of the TOE without the need of management roles.
FMT_CFG.1 is not hierarchical to any other component within the FMT_CFG family.
FMT_CFG.2 specifies TOE configuration value initialization.
FMT_CFG.2 is not hierarchical to any other component within the FMT_CFG family.
Management: FMT_CFG.1
There are no management activities foreseen.
Management: FMT_CFG.2
There are no management activities foreseen.
Audit: FMT_CFG.1
The following actions should be auditable if FAU_GEN Security audit data generation is
included in the PP/ST:
a) Minimal: Changes of the TOE configuration.
Audit: FMT_CFG.2
There are no audit events foreseen.
5.1.1.1 FMT_CFG.1 - Configuration of security functions
Hierarchical to: No other components.
Dependencies: No dependencies.
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FMT_CFG.1.1 The TSF shall be capable of configuring the following security
functions: [assignment: list of functions to be configurable by the
TSF].
Rationale
The configuration of the TOE is specified with a configuration method that is not dependent
on TOE supported roles.
5.1.1.2 FMT_CFG.2 - Configuration value initialization
Hierarchical to: No other components.
Dependencies: No dependencies.
FMT_CFG.2.1 The TSF shall enforce the [assignment: access control SFP,
information flow control SFP] to provide [selection, choose one of:
restrictive, permissive, [assignment: other property]] default values
for security attributes that are used to enforce the SFP.
FMT_CFG.2.2 The TSF shall support the specification of alternative initial values
to override the default values used in enforcing the security policy.
Rationale
The defaults of the TOE configuration are specified with a configuration method that is not
dependent on TOE supported roles.
6 Security Requirements
6.1 TOE Security Functional Requirements
The following table shows the Security functional requirements for the TOE, and the
operations performed on the components according to CC part 2: iteration (Iter.), refinement
(Ref.), assignment (Ass.) and selection (Sel.).
Table 18: Security functional requirements for the TOE
Security
functional
group
Security functional
requirement
Base security
functional
component
Source Operations
Iter. Ref. Ass. Sel.
Crypto.
Support
FCS_CKM.1(RNG) FCS_CKM.1 [CC] X X X
FCS_CKM.1(RSA) FCS_CKM.1 [CC] X X
FCS_CKM.2 FCS_CKM.2 [CC] X X
FCS_CKM.4 FCS_CKM.4 [CC] X
FCS_COP.1(TLS) FCS_COP.1 [CC] X X X
FCS_COP.1(CERT) FCS_COP.1 [CC] X X X
FCS_RNG.1 FCS_RNG.1 [KS2
011]
X X X
JWT TLS FDP_IFC.1(JWT) FDP_IFC.1 [CC] X X
FDP_IFF.1(JWT) FDP_IFF.1 [CC] X X
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Security
functional
group
Security functional
requirement
Base security
functional
component
Source Operations
Iter. Ref. Ass. Sel.
FDP_ITT.1 FDP_ITT.1 [CC] X X
FDP_ITT.3 FDP_ITT.3 [CC] X
FMT_CFG.2(JWT) FMT_CFG.2 ECD X X X
HTTPS FDP_IFC.1(HTTPS) FDP_IFC.1 [CC] X X
FDP_IFF.1(HTTPS) FDP_IFF.1 [CC] X X
FMT_CFG.2(HTTPS) FMT_CFG.2 ECD X X X
FTP_ITC.1 FTP_ITC.1 [CC] X X X
I&A and
Auth.
FDP_IFC.2 FDP_IFC.2 [CC] X
FDP_IFF.1(WSP) FDP_IFF.1 [CC] X X
FIA_ATD.1 FIA_ATD.1 [CC] X
FIA_UAU.1 FIA_UAU.1 [CC] X
FIA_UID.1 FIA_UID.1 [CC] X
FIA_USB.1 FIA_USB.1 [CC] X
FMT_CFG.2(WSP) FMT_CFG.2 ECD X X X
FMT_CFG.1 FMT_CFG.1 ECD X
6.1.1 Information flow control policy models
6.1.1.1 Information flow control policy model (JWT)
The security policy for the JWT TLS information flow control policy is defined by the security
functional requirements in section 6.1.3. The following is a list of the subjects and resources
participating in the policy.
• Subject:
◦ HOBLink JWT component acting as the client
◦ WSP component acting as the server
• Information security attribute:
◦ Established TLS connection for each X.509 certificate:
▪ Digital signature generated with the X.509 certificate,
▪ Distinguished Name (DN) stored in an X.509 certificate,
▪ Validity period of X.509 certificate,
▪ BasicConstraints
• Resources:
◦ Protected Remote Desktop servers;
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• Operation:
◦ all data transmissions between the HOBLink JWT component and the WSP
component
• User data:
◦ All RDP data exchanged between the resources managed by the WSP and the
HOBLink JWT.
6.1.1.2 Information flow control policy model (HTTPS)
The security policy for the HTTPS information flow control policy is defined by the security
functional requirements in section 6.1.4. The following is a list of the subjects and resources
participating in the policy.
• Subjects:
◦ remote trusted entity acting as the client
◦ WSP component acting as the server
• Information security attribute:
◦ Established TLS connection
• Resources:
◦ Protected external web servers;
◦ WSP-integrated web server;
• Operation:
◦ all data transmissions between the remote trusted entity and the WSP
component
• User data:
◦ All data transmissions between the remote trusted entity and the WSP
component;
6.1.1.3 Information flow control policy model (WSP)
The security policy for the WSP information flow control policy is defined by the security
functional requirements in section 6.1.5. The following is a list of the subjects and resources
participating in the policy.
• Subject:
◦ Authenticated users represented by an HTTP session cookie.
Note: Within the same browser on the same machine there is only one cookie for
an authenticated user that is used for all connection types. This is the HTTP
session cookie that is created when the “integrated web server” presents the
start web page.
◦ Authenticated users represented by an established TLS connection for JWT
connections.
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• Subject security attributes:
◦ Role assigned to the authenticated user of the subject,
◦ HTTPS connections: HTTP session cookie,
◦ JWT connections: Established TLS connection between HOBLink JWT and the
WSP component.
• Resources:
◦ Protected Remote Desktop servers;
◦ Protected external web servers;
◦ WSP-integrated web server.
• TSF data:
◦ Configuration information used by the WSP defining the resource access list
where access rights are assigned to roles. Therefore, users are also assigned to
roles as part of the resource access list.
• User data:
◦ All data exchanged between the resources managed by the WSP and the
subjects.
6.1.2 Cryptographic support
6.1.2.1 Cryptographic key generation (FCS_CKM.1(RNG))
FCS_CKM.1.1 The TSF shall generate symmetric cryptographic keys in accordance with a
specified cryptographic key generation algorithm capable of generating a
random bit sequence7
and specified cryptographic key sizes:
• AES: 128 bits,
• HMAC-SHA1: 160 bits,
• HMAC-SHA256: 256 bits8
that meet the following: cryptographic key generation with random bits
generated by:
• TLS: generation and exchange of pre-master secrets as defined
in the TLSv1.1 protocol [RFC4346] or in the TLSv1.2 protocol
[RFC5246] with the cipher suites defined in FCS_COP.1(TLS)9
.
6.1.2.2 Cryptographic key generation (FCS_CKM.1(RSA))
FCS_CKM.1.1 The TSF shall generate cryptographic keys in accordance with a specified
cryptographic key generation algorithm defined in [FIPS186-3] appendix
B.3.310
and specified cryptographic key sizes:
7
[assignment: cryptographic key generation algorithm]
8
[assignment: cryptographic key sizes]
9
[assignment: list of standards]
10
[assignment: cryptographic key generation algorithm]
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• 1536 bits
• 2048 bits11
that meet the following: [FIPS186-3]12
.
Application Note: The primes used for the RSA key are generated based on random
numbers derived out of the RNG specified in FCS_RNG.1. The TOE uses the Miller-Rabin
test to validate that the random values are prime. Therefore, the primes are considered
“probable prime”.
Application Note: The prime requirements for the RSA keys are derived from [FIPS186-3]
appendix B.3.3 and the minimum number of rounds of M-R testing is determined according
to table C.3 in [FIPS186-3]. To define the number of necessary rounds in the Miller-Rabin
test for values of prime numbers for RSA key sizes (such as 1536 bits) that are not listed in
the table the following methods shall be used. The intermediate value for sizes of prime
numbers are determined by the larger number of rounds of the next smaller size of a prime
number found in the table. This is equal to the value of rounds for the primes p = 512 and q =
512 in the case of a 1536 bit RSA key. Alternatively the number of rounds for a 1536 bit RSA
key may be approximated by a linear interpolation of the requirements for the surrounding
key sizes 1024 bits and 2048 bits.
Application Note: The algorithm for the RSA key generation as described in appendix B.3.3 of
[FIPS186-3] is not fully congruent with the actual implementation in the source code. The
details of the differences are outlined in the TOE design documentation. It is claimed that the
parameters created from the implemented RSA key generation will pass all conditions as
specified in appendix B.3.3 of [FIPS186-3], except for item 1., which restricts possible key
sizes, and the random extraction iteration limit. The TOE design documentation provides the
necessary information to prove this claim.
Application Note: The RSA key generation mechanism is used to generate all RSA keys
required by the TOE, including root keys, potentially intermediate keys, and leaf keys.
6.1.2.3 Cryptographic key distribution (FCS_CKM.2)
FCS_CKM.2.1 The TSF shall distribute cryptographic keys in accordance with a the
following specified cryptographic key distribution methods [assignment:
cryptographic key distribution method] that meets the following:
a) RSA encryption of cryptographic sensitive parameters as
defined in [RFC4346] and [RFC5246];
b) Transmission of the client HOBLink Security Unit from the WSP
to the “HOBLink Secure, Client” using the established TLS
channel specified by the “HOB HTTPS information flow control
policy”1314
;
c) TLS server certificate distribution as defined in [RFC4346] and
[RFC5246].
Application Note: The TLS channel ends at the client browser whereas the client HOBLink
Security Unit is fed into the “HOBLink Secure, Client” by the client browser.
11
[assignment: cryptographic key sizes]
12
[assignment: list of standards]
13
[assignment: cryptographic key distribution method]
14
[assignment: list of standards]
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6.1.2.4 Cryptographic key destruction (FCS_CKM.4)
FCS_CKM.4.1 The TSF shall destroy cryptographic keys in accordance with a specified
cryptographic key destruction method overwriting with zeros15
that meets
the following: vendor-specific zeroization16
.
Application Note: The "vendor-specific zeroization" covers the following concepts:
• Memory objects: Overwriting the memory with zeros at the time the memory is not
further required.
6.1.2.5 Cryptographic operation (FCS_COP.1(TLS))
FCS_COP.1.1 The TSF shall perform encryption, decryption, integrity verification, peer
authentication17
in accordance with a specified the following cryptographic
algorithms [assignment: cryptographic algorithm] and, cryptographic key
sizes [assignment: cryptographic key sizes] that meet the following:
[assignment: list of standards] and applicable standards:
a) TLS version 1.1 defined by [RFC4346] with the following
properties:
◦ AES defined in [FIPS197] in CBC mode defined by [SP800-
38A] with 128 bits key size,
◦ HMAC defined by [RFC2104],
◦ SHA-1 defined by [FIPS180] used for the pseudo-random
function and MAC,
◦ MD5 defined by [RFC1321] used for the pseudo-random
function only,
◦ RSA with a key size of either 1536 or 2048 bits;
b) TLS version 1.2 defined by [RFC5246] with the following
properties:
◦ AES defined in [FIPS197] in CBC mode defined by [SP800-
38A] with 128 bits key size,
◦ HMAC defined by [RFC2104],
◦ SHA-1 defined by [FIPS180] used for MAC,
◦ SHA-256 defined by [FIPS180] used for the pseudo-random
function and MAC,
◦ RSA with a key size of either 1536 or 2048 bits.181920
Application Note: For TLSv1.1, the following cipher suite is implemented:
TLS_RSA_WITH_AES_128_CBC_SHA. Any other cipher suite defined in the RFC is not
implemented.
15
[assignment: cryptographic key destruction method]
16
[assignment: list of standards]
17
[assignment: list of cryptographic operations]
18
[assignment: cryptographic algorithm]
19
[assignment: cryptographic key sizes]
20
[assignment: list of standards]
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Application Note: For TLSv1.2, the following cipher suites are implemented:
TLS_RSA_WITH_AES_128_CBC_SHA and TLS_RSA_WITH_AES_128_CBC_SHA256.
Any other cipher suite defined in the RFC is not implemented.
Application Note: The protocols of TLSv1.1 and TLSv1.2 are implemented with the
RSAES-PKCS1-v1_5 encryption scheme defined in [PKCS1].
6.1.2.6 Cryptographic operation (FCS_COP.1(CERT))
FCS_COP.1.1 The TSF shall perform signature generation and verification21
in
accordance with a specified the following cryptographic algorithms
[assignment: cryptographic algorithm] and, cryptographic key sizes
[assignment: cryptographic key sizes] that meet the following: [assignment:
list of standards] and applicable standards:
a) Signing of an X.509 certificate defined by [RFC5280] using :
◦ RSA with key size of either 1536 bits or 2048 bits
◦ SHA-1, SHA-256;
b) Verification of an X.509 certificate defined by [RFC5280] using:
◦ RSA with key size of either 1536 bits or 2048 bits
◦ SHA-1, SHA-256.222324
Application Note: Padding is implemented based on the RSASSA-PKCS1-v1_5 signature
scheme defined in [PKCS1].
6.1.2.7 Random number generation (Class DRG.3) (FCS_RNG.1)
FCS_RNG.1.1 The TSF shall provide a deterministic random number generator that
implements:
a) DRG.3.1: If initialized with a random seed using timing of key
strokes by users, timing of movement of mouse by users,
variances of CPU load, timing of OS API calls, Linux
"/dev/random" output, timing of TCP handshake as random
source25
, the internal state of the RNG shall have a Min-entropy26
of 48 bits27
.
b) DRG.3.2: The DRNG provides forward secrecy.
c) DRG.3.3: The DRNG provides backward secrecy even if the current
internal state is known.
FCS_RNG.1.2 The TSF shall provide random numbers that meet:
21
[assignment: list of cryptographic operations]
22
[assignment: cryptographic algorithm]
23
[assignment: cryptographic key sizes]
24
[assignment: list of standards]
25
[selection: using PTRNG of class PTG.2 as random source, using PTRNG of class PTG.3 as random source,
using NPTRNG of class NTG.1 as random source, [assignment: other requirements for seeding]]
26
defined in [KS2011]
27
[selection: have [assignment: amount of entropy], have [assignment: work factor], require [assignment: guess
work]]
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a) DRG.3.4: The RNG initialized with a random seed at initialization
time of the DRNG28
generates output for which 2**3229
strings of bit
length 128 are mutually different with probability of greater than 1-
2**-1030
.
b) DRG.3.5: Statistical test suites cannot practically distinguish the
random numbers from output sequences of an ideal RNG. The
random numbers must pass test procedure A31
.
Application Note: The TOE implements the CTR_DRBG with AES 128 core according to the
specification of NIST SP800-90A.
Application Note: The TOE implements the specified RNG in the following components:
• the WSP implements one RNG for handling the TLS connections and the HTTP
session cookie generation,
• the HOBLink Security Manager implements the RNG to support the key and
certificate generation, and
• the HOBLink JWT implementing one RNG for handling the TLS connections.
Application Note: The TOE implements the specified RNG which uses the following random
sources in the following components:
• the WSP initializes the RNG using variances of CPU load, timing of OS API calls,
Linux "/dev/random" output and timing of TCP handshake,
• the HOBLink Security Manager initializes the RNG using timing of key strokes by
users and timing of movement of mouse by users, and
• the HOBLink JWT initializes the RNG using timing of key strokes by users and
timing of movement of mouse by users.
6.1.3 JWT TLS connectivity
6.1.3.1 Subset information flow control (FDP_IFC.1(JWT))
FDP_IFC.1.1 The TSF shall enforce the JWT TLS information flow control policy32
on
• Subjects:
◦ HOBLink JWT component acting as the client
◦ WSP component acting as the server
• Information:
◦ all encapsulated RDP user data,
◦ X.509 certificate
• Operation:
28
[assignment: requirements for seeding]
29
[assignment: number of strings]
30
[assignment: probability]
31
[assignment: additional test suites]
32
[assignment: information flow control SFP]
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◦ all data transmissions between the HOBLink JWT
component and the WSP component33
.
6.1.3.2 Simple security attributes (FDP_IFF.1(JWT))
FDP_IFF.1.1 The TSF shall enforce the JWT TLS information flow control policy34
based on the following types of subject and information security attributes:
• Information security attributes:
◦ RDP user data: Established TLS connection,
◦ For each X.509 certificate:
▪ Digital signature generated with the X.509 certificate,
▪ Distinguished Name (DN) stored in an X.509 certificate,
▪ Validity period of X.509 certificate,
▪ BasicConstraints35
.
FDP_IFF.1.2 The TSF shall permit an information flow between a controlled subject and
controlled information via a controlled operation if the following rules hold:
• “HOBLink Secure, Server” within the WSP component
presents an X.509v3 certificate according to [RFC5280] to
“HOBLink Secure, Client” within the HOBLink JWT component
and “HOBLink Secure, Client” within the HOBLink JWT
supported by HOBLink JWT performs the following validity
checks:
1. For server certificate:
◦ Validity of digital signature of X.509 certificate
presented by peer,
◦ Validity period of X.509 certificate started and did
not end,
◦ The Common Name part of the Distinguished Name
component stored in the X.509 certificate matches
either:
◦ the IP address of the WSP server, or
◦ the DNS name of the WSP server;
2. Certificate chain validation: If current certificate is not
the root certificate known to the validation mechanism,
the following checks are performed for each certificate
of the certificate chain that signed the current server
certificate and all intermediate certificates:
33
[assignment: list of subjects, information, and operations that cause controlled information to flow to and from
controlled subjects covered by the SFP]
34
[assignment: information flow control SFP]
35
[assignment: list of subjects and information controlled under the indicated SFP, and for each, the security
attributes]
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◦ Validity of digital signature of signed X.509
certificate,
◦ Validity period of X.509 certificate started and did
not end,
◦ BasicConstraints mark the certificate as a CA or
sub-CA certificate,
◦ Root certificate is self signed and is already known
to the validation mechanism, and
◦ Chain of certificate signatures leading from the root
certificate to the server certificate is complete.
• “HOBLink Secure, Server” within the WSP component and
“HOBLink Secure, Client” within the HOBLink JWT component
ensure that a communication link using either of the following
protocols is successfully established:
◦ TLS version 1.1
◦ TLS version 1.236
.
FDP_IFF.1.3 The TSF shall enforce the no other information flow control SFP rules37
.
FDP_IFF.1.4 The TSF shall explicitly authorise an information flow based on the following
rules: none38
.
FDP_IFF.1.5 The TSF shall explicitly deny an information flow based on the following
rules: none39
.
6.1.3.3 Basic internal transfer protection (FDP_ITT.1)
FDP_ITT.1.1 The TSF shall enforce the JWT TLS information flow control policy40
to
prevent the disclosure, modification41
of user data when it is transmitted
between physically-separated parts of the TOE.
6.1.3.4 Integrity monitoring (FDP_ITT.3)
FDP_ITT.3.1 The TSF shall enforce the JWT TLS information flow control policy42
to
monitor user data transmitted between physically-separated parts of the TOE
for the following errors:
• modification of data,
• reordering of data,
• deletion of data,
• insertion of data,
36
[assignment: for each operation, the security attribute-based relationship that must hold between subject and
information security attributes]
37
[assignment: additional information flow control SFP rules]
38
[assignment: rules, based on security attributes, that explicitly authorise information flows]
39
[assignment: rules, based on security attributes, that explicitly deny information flows]
40
[assignment: access control SFP(s) and/or information flow control SFP(s)]
41
[selection: disclosure, modification, loss of use]
42
[assignment: access control SFP(s) and/or information flow control SFP(s)]
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• replay of data43
.
FDP_ITT.3.2 Upon detection of a data integrity error, the TSF shall terminate the TLS
session and inform the application about the reason of the
termination44
.
6.1.3.5 Configuration value initialization (FMT_CFG.2(JWT))
FMT_CFG.2.1 The TSF shall enforce the JWT TLS information flow control policy45
to
provide restrictive46
default values for security attributes that are used to
enforce the SFP.
FMT_CFG.2.2 The TSF shall support the specification of alternative initial values to override
the default values used in enforcing the security policy.
6.1.4 HTTPS connectivity
6.1.4.1 Subset information flow control (FDP_IFC.1(HTTPS))
FDP_IFC.1.1 The TSF shall enforce the HOB HTTPS information flow control policy47
on
• Subjects:
◦ remote trusted entity acting as the client
◦ WSP component acting as the server
• Information:
◦ all encapsulated web user data,
◦ HOBLink JWT webstart application and client HOBLink
Security Unit
• Operation:
◦ all data transmissions between the remote trusted entity
and the WSP component48
.
6.1.4.2 Simple security attributes (FDP_IFF.1(HTTPS))
FDP_IFF.1.1 The TSF shall enforce the HOB HTTPS information flow control policy49
based on the following types of subject and information security attributes:
• Information security attribute:
◦ Established TLS connection50
.
43
[assignment: integrity errors]
44
[assignment: specify the action to be taken upon integrity error]
45
[assignment: access control SFP, information flow control SFP]
46
[selection, choose one of: restrictive, permissive, [assignment: other property]]
47
[assignment: information flow control SFP]
48
[assignment: list of subjects, information, and operations that cause controlled information to flow to and from
controlled subjects covered by the SFP]
49
[assignment: information flow control SFP]
50
[assignment: list of subjects and information controlled under the indicated SFP, and for each, the security
attributes]
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FDP_IFF.1.2 The TSF shall permit an information flow between a controlled subject and
controlled information via a controlled operation if the following rules hold:
• “HOBLink Secure, Server” within the WSP component ensures
that a communication link using either of the following
protocols is successfully established:
◦ TLS version 1.1
◦ TLS version 1.251
.
FDP_IFF.1.3 The TSF shall enforce the no other information flow control SFP rules52
.
FDP_IFF.1.4 The TSF shall explicitly authorise an information flow based on the following
rules: none53
.
FDP_IFF.1.5 The TSF shall explicitly deny an information flow based on the following
rules: none54
.
6.1.4.3 Configuration value initialization (FMT_CFG.2(HTTPS))
FMT_CFG.2.1 The TSF shall enforce the HOB HTTPS information flow control policy55
to provide restrictive56
default values for security attributes that are used to
enforce the SFP.
FMT_CFG.2.2 The TSF shall support the specification of alternative initial values to override
the default values used in enforcing the security policy.
6.1.4.4 Inter-TSF trusted channel (FTP_ITC.1)
FTP_ITC.1.1 The TSF shall provide a communication channel between itself and another
trusted IT product that is logically distinct from other communication
channels and provides assured identification of its end points and protection
of the channel data from modification orand disclosure using the following
mechanisms: Cryptographically-protected communication channel
using:
• TLS v1.1, or
• TLS v1.2.
FTP_ITC.1.2 The TSF shall permit another trusted IT product57
to initiate
communication via the trusted channel.
FTP_ITC.1.3 The TSF shall initiate communication via the trusted channel for
communication with the external entity58
.
Application Note: The SFR applies to the communication between the client Browser and the
WSP.
51
[assignment: for each operation, the security attribute-based relationship that must hold between subject and
information security attributes]
52
[assignment: additional information flow control SFP rules]
53
[assignment: rules, based on security attributes, that explicitly authorise information flows]
54
[assignment: rules, based on security attributes, that explicitly deny information flows]
55
[assignment: access control SFP, information flow control SFP]
56
[selection, choose one of: restrictive, permissive, [assignment: other property]]
57
[selection: the TSF, another trusted IT product]
58
[assignment: list of functions for which a trusted channel is required]
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6.1.5 Identification, Authentication and Authorization
6.1.5.1 Complete information flow control (FDP_IFC.2)
FDP_IFC.2.1 The TSF shall enforce the WSP information flow control policy59
on
• Subjects:
◦ HTTPS connections: Authenticated users represented by
the HTTP session cookie;
◦ JWT connections: Authenticated users represented by an
established TLS connection;
• Information
◦ All data flowing between subjects and resources of web
servers and Remote Desktop servers protected by the
WSP;60
and all operations that cause that information to flow to and from subjects
covered by the SFP.
FDP_IFC.2.2 The TSF shall ensure that all operations that cause any information in the
TOE to flow to and from any subject in the TOE are covered by an
information flow control SFP.
6.1.5.2 Simple security attributes (FDP_IFF.1(WSP))
FDP_IFF.1.1 The TSF shall enforce the WSP information flow control policy61
based on
the following types of subject and information security attributes:
• Subject security attributes:
◦ Role assigned to the authenticated user of the subject,
◦ HTTPS connections: HTTP session cookie,
◦ JWT connections: Established TLS connection between
HOBLink JWT and the WSP component62
.
FDP_IFF.1.2 The TSF shall permit an information flow between a controlled subject and
controlled information via a controlled operation if the following rules hold:
the subject's information flow to the protected resources of web
servers or Remote Desktop servers is allowed if
• subject presents either:
◦ ticket and user information encode in an HTTP session
cookie,
◦ or submits the data via an established TLS connection
between HOBLink JWT and the WSP component
59
[assignment: information flow control SFP]
60
[assignment: list of subjects and information]
61
[assignment: information flow control SFP]
62
[assignment: list of subjects and information controlled under the indicated SFP, and for each, the security
attributes]
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that allows the WSP to verify that the request is part of an
active session, and
• the accessed resource is listed in the access lists assigned to
the role the user represented the active session is mapped to63
.
FDP_IFF.1.3 The TSF shall enforce the no other information flow control SFP rules64
.
FDP_IFF.1.4 The TSF shall explicitly authorise an information flow based on the following
rules: none65
.
FDP_IFF.1.5 The TSF shall explicitly deny an information flow based on the following
rules: none66
.
Application Note: After successful I&A, the state of a connection is maintained as follows:
• As HTTP is a stateless protocol, the state is maintained by the HTTP session cookie
and the user must always transmit the HTTP session cookie with each request to
map the request to the initially identified user;
• The connection between WSP and JWT is a stateful TLS channel where each
request submitted via this established TLS channel is implicitly assigned to the
initially identified user.
6.1.5.3 User attribute definition (FIA_ATD.1)
FIA_ATD.1.1 The TSF shall maintain the following list of security attributes belonging to
individual users:
• zero or more ephemeral HTTP session cookies;
• zero or more ephemeral network connection from the HOBLink
JWT component67
.
Application Note: The identification and authentication is performed by requiring a
username/password combination to be entered by the user. These credentials are used to
perform an LDAP-bind operation to verify these credentials. Since the LDAP server performs
the identification/authentication decision and the TOE enforces this decision, the TOE does
not maintain or require any of the credentials.
6.1.5.4 Timing of authentication (FIA_UAU.1)
FIA_UAU.1.1 The TSF shall allow
• initiation of the TLS connection tunneling the HTTP requests,
• access to the logon web page offered by the WSP68
on behalf of the user to be performed before the user is authenticated.
FIA_UAU.1.2 The TSF shall require each user to be successfully authenticated before
allowing any other TSF-mediated actions on behalf of that user.
63
[assignment: for each operation, the security attribute-based relationship that must hold between subject and
information security attributes]
64
[assignment: additional information flow control SFP rules]
65
[assignment: rules, based on security attributes, that explicitly authorise information flows]
66
[assignment: rules, based on security attributes, that explicitly deny information flows]
67
[assignment: list of security attributes]
68
[assignment: list of TSF mediated actions]
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6.1.5.5 Timing of identification (FIA_UID.1)
FIA_UID.1.1 The TSF shall allow
• initiation of the TLS connection tunneling the HTTP requests,
• access to the logon web page offered by the WSP69
on behalf of the user to be performed before the user is identified.
FIA_UID.1.2 The TSF shall require each user to be successfully identified before allowing
any other TSF-mediated actions on behalf of that user.
6.1.5.6 User-subject binding (FIA_USB.1)
FIA_USB.1.1 The TSF shall associate the following user security attributes with subjects
acting on the behalf of that user:
• HTTPS connection: HTTP session cookie,
• JWT connection:
◦ HTTP session cookie for the authentication after the
establishment of the JWT TLS connection, and
◦ an established TLS connection70
.
FIA_USB.1.2 The TSF shall enforce the following rules on the initial association of user
security attributes with subjects acting on the behalf of users:
• HTTPS connection: Upon successful identification and
authentication, WSP issues a unique HTTP session cookie
which the WSP relates to the current HTTPS connection;
• JWT connection: The establishment of a JWS connection
requires a valid and established HTTPS connection where the
JWS connection re-uses and re-submits the existing HTTP
session cookie which the WSP relates to newly initiated JWT
connection71
.
FIA_USB.1.3 The TSF shall enforce the following rules governing changes to the user
security attributes associated with subjects acting on the behalf of users:
none72
.
6.1.5.7 Configuration value initialization (FMT_CFG.2(WSP))
FMT_CFG.2.1 The TSF shall enforce the WSP information flow control policy73
to
provide restrictive74
default values for security attributes that are used to
enforce the SFP.
FMT_CFG.2.2 The TSF shall support the specification of alternative initial values to override
the default values used in enforcing the security policy.
69
[assignment: list of TSF mediated actions]
70
[assignment: list of user security attributes]
71
[assignment: rules for the initial association of attributes]
72
[assignment: rules for the changing of attributes]
73
[assignment: access control SFP, information flow control SFP]
74
[selection, choose one of: restrictive, permissive, [assignment: other property]]
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Application Note: The restrictive default values apply to the allowed information flow: if the
administrator did not specify any information flow rules, no connection is allowed by the
WSP. Only when rules are specified, WSP allows communication based on those rules and
denies any other traffic.
6.1.5.8 Configuration of security functions (FMT_CFG.1)
FMT_CFG.1.1 The TSF shall be capable of configuring the following security functions:
access control via access lists specifying the allowed resources
protected by the WSP holding the following information:
• access control rules mapping resources to roles,
• role specifications mapping users to roles75
.
6.2 Security Functional Requirements Rationale
6.2.1 Coverage
The following table provides a mapping of SFR to the security objectives, showing that each
security functional requirement addresses at least one security objective.
Table 19: Mapping of security functional requirements to security objectives
Security Functional Requirements Objectives
FCS_CKM.1(RNG) O.Crypto.Net
FCS_CKM.1(RSA) O.Certificates
FCS_CKM.2 O.Crypto.Net
FCS_CKM.4 O.Crypto.Net,
O.Certificates
FCS_COP.1(TLS) O.Crypto.Net
FCS_COP.1(CERT) O.Certificates,
O.CryptoNet
FCS_RNG.1 O.Crypto.Net,
O.Certificates,
O.I&A
FDP_IFC.1(JWT) O.Crypto.Net
FDP_IFF.1(JWT) O.Crypto.Net
FDP_ITT.1 O.Crypto.Net
FDP_ITT.3 O.Crypto.Net
FMT_CFG.2(JWT) O.Crypto.Net
FDP_IFC.1(HTTPS) O.Crypto.Net
FDP_IFF.1(HTTPS) O.Crypto.Net
FMT_CFG.2(HTTPS) O.Crypto.Net
FTP_ITC.1 O.CryptoNet
FDP_IFC.2 O.Resource.Access
75
[assignment: list of functions to be configurable by the TSF]
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Security Functional Requirements Objectives
FDP_IFF.1(WSP) O.Resource.Access
FIA_ATD.1 O.I&A
FIA_UAU.1 O.I&A
FIA_UID.1 O.I&A
FIA_USB.1 O.I&A
FMT_CFG.2(WSP) O.Resource.Access
FMT_CFG.1 O.Resource.Access
6.2.2 Sufficiency
The following rationale provides justification for each security objective for the TOE, showing
that the security functional requirements are suitable to meet and achieve the security
objectives:
Table 20: Security objectives for the TOE rationale
Security
objectives
Rationale
O.Certificates The objective that the TOE provides the facility to generate RSA
certificates and the corresponding keys is implemented with:
• FCS_CKM.1(RSA) defining the RSA key generation mechanism
and creating X.509 certificates from the RSA keys
(FCS_COP.1(CERT)).
• FCS_CKM.4 which zeroizes the memory used for RSA keys.
• FCS_RNG.1 supporting the key generation by providing random
numbers.
O.Crypto.Net The objective that the TSF must be designed and implemented in a
manner that allows for establishing a trusted channel between the TOE
and a remote trusted IT system that protects the user data and TSF
data transferred over this channel from disclosure and undetected
modification and prevents masquerading of the remote trusted IT
system is implemented with:
• Providing cryptographic primitives for key generation
(FCS_CKM.1(RNG)) supported by a deterministic RNG as defined
in FCS_RNG.1;
• Providing the cryptographic protocol of TLS including the key and
certificate exchange mechanism (FCS_CKM.2,
FCS_COP.1(TLS), FCS_COP.1(CERT));
• Zeroization of key material and other ephemeral cryptographic
sensitive data (FCS_CKM.4);
• Use and definition of properties of the TLS channel with uni-
directional certificate validation used by the HOBLink JWT
component connecting to the WSP component (FDP_IFC.1(JWT),
FDP_IFF.1(JWT), FDP_ITT.1, FDP_ITT.3, FMT_CFG.2(JWT));
• Use and definition of properties of the TLS channel used by the
environmental web browser connecting to the WSP component
(FDP_IFC.1(HTTPS), FDP_IFF.1(HTTPS), FMT_CFG.2(HTTPS),
FTP_ITC.1).
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Security
objectives
Rationale
O.I&A The objective that the TOE must ensure that users have been
successfully authenticated before allowing any action the TOE has
defined to provide to authenticated users only is implemented with:
• Generation of the HTTPS session cookie (FCS_RNG.1);
• Maintenance of ephemeral user data (FIA_ATD.1);
• Specification of the identification and authentication method
(FIA_UAU.1, FIA_UID.1);
• Definition of the user-subject binding mechanism (FIA_USB.1).
O.Resource.
Access
The objective that the TSF must control access of subjects and/or
users to the resources of web servers and Remote Desktop servers
based on identity of the resource is implemented by:
• The information flow control policy that governs the access of
subjects to resources (FDP_IFC.2, FDP_IFF.1(WSP),
FMT_CFG.2(WSP));
• Management interface for the information flow control policy
(FMT_CFG.1).
6.2.3 Security requirements dependency analysis
The following table demonstrates the dependencies of SFRs modeled in CC Part 2 and how
the SFRs for the TOE resolve those dependencies:
Table 21: TOE SFR dependency analysis
Security Functional
Requirements
Dependencies Resolution
FCS_CKM.1(RNG) [FCS_CKM.2 or
FCS_COP.1]
FCS_CKM.4
Yes: FCS_CKM.2, FCS_COP.1(TLS)
Yes: FCS_CKM.4
FCS_CKM.1(RSA) [FCS_CKM.2 or
FCS_COP.1]
FCS_CKM.4
Yes: FCS_CKM.2, FCS_COP.1
Yes: FCS_CKM.4, covering the copies of the
RSA keys in memory.
Uncovered: FCS_CKM.4 – The objective for
the environment OE.DestroyRSA ensures that
environmental procedures are in place that
ensure the destruction of long-lived RSA keys.
Uncovered: FCS_CKM.2 for the distribution of
keys between the HOBLink Security Manager
and the WSP which is covered by OE.SecMgr.
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Security Functional
Requirements
Dependencies Resolution
FCS_CKM.2 [FDP_ITC.1 or
FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
Yes: FCS_CKM.1(RNG) and
FCS_CKM.1(RSA)
Yes: FCS_CKM.4
FCS_CKM.4 [FDP_ITC.1 or
FDP_ITC.2 or
FCS_CKM.1]
Yes: FCS_CKM.1(RNG), FCS_CKM.1(RSA)
FCS_COP.1(TLS) [FDP_ITC.1 or
FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
Yes: FCS_CKM.1(RNG) and
FCS_CKM.1(RSA)
Yes: FCS_CKM.4
FCS_COP.1(CERT) [FDP_ITC.1 or
FDP_ITC.2 or
FCS_CKM.1]
FCS_CKM.4
Yes: FCS_CKM.1(RSA)
Yes: FCS_CKM.4
FCS_RNG.1 No dependencies Yes
FDP_IFC.1(JWT) FDP_IFF.1 Yes: FDP_IFF.1(JWT)
FDP_IFF.1(JWT) FDP_IFC.1
FDP_MSA.3
Yes: FDP_IFC.1(JWT)
NO: The TOE does not support administrative
roles. Therefore the configuration aspects are
covered by FMT_CFG.2(JWT) instead of
FMT_MSA.3.
FDP_ITT.1 [FDP_ACC.1 or
FDP_IFC.1]
Yes: FDP_IFC.1(JWT)
FDP_ITT.3 [FDP_ACC.1 or
FDP_IFC.1]
FDP_ITT.1
Yes: FDP_IFC.1(JWT)
Yes: FDP_ITT.1
FMT_CFG.2(JWT) No dependencies Yes
FDP_IFC.1(HTTPS) FDP_IFF.1 Yes: FDP_IFF.1(HTTPS)
FDP_IFF.1(HTTPS) FDP_IFC.1
FDP_MSA.3
Yes: FDP_IFC.1(HTTPS)
NO: The TOE does not support administrative
roles. Therefore the configuration aspects are
covered by FMT_CFG.2(HTTPS) instead of
FMT_MSA.3.
FMT_CFG.2(HTTPS) No dependencies Yes
FTP_ITC.1 No dependencies Yes.
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Security Functional
Requirements
Dependencies Resolution
FDP_IFC.2 FDP_IFF.1 Yes: FDP_IFF.1(WSP)
FDP_IFF.1(WSP) FDP_IFC.1
FDP_MSA.3
Yes: FDP_IFC.2
Yes: FMT_CFG.2(WSP)
FIA_ATD.1 No dependencies Yes
FIA_UAU.1 FIA_UID.1 Yes: FIA_UID.1
FIA_UID.1 No dependencies
FIA_USB.1 FIA_ATD.1 Yes: FIA_ATD.1
FMT_CFG.2(WSP) No
dependencies
Yes
FMT_CFG.1 No
dependencies
Yes
6.3 Security Assurance Requirements
The security assurance requirements for the TOE are the EAL4 components as specified in
[CC] part 3, augmented by ALC_FLR.2.
The following table shows the Security assurance requirements, and the operations
performed on the components according to CC part 3: iteration (Iter.), refinement (Ref.),
assignment (Ass.) and selection (Sel.).
Table 22: Security assurance requirements
Security
assurance
class
Security assurance requirement Source Operations
Iter. Ref. Ass. Sel.
ADV ADV_ARC.1 CC Part 3
ADV_FSP.4 CC Part 3
ADV_IMP.1 CC Part 3
ADV_TDS.3 CC Part 3
AGD AGD_OPE.1 CC Part 3
AGD_PRE.1 CC Part 3
ALC ALC_CMC.4 CC Part 3
ALC_CMS.4 CC Part 3
ALC_DEL.1 CC Part 3
ALC_DVS.1 CC Part 3
ALC_FLR.2 CC Part 3
ALC_LCD.1 CC Part 3
ALC_TAT.1 CC Part 3
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Security
assurance
class
Security assurance requirement Source Operations
Iter. Ref. Ass. Sel.
ASE ASE_INT.1 CC Part 3
ASE_CCL.1 CC Part 3
ASE_SPD.1 CC Part 3
ASE_OBJ.2 CC Part 3
ASE_ECD.1 CC Part 3
ASE_REQ.2 CC Part 3
ASE_TSS.1 CC Part 3
ATE ATE_COV.2 CC Part 3
ATE_DPT.1 CC Part 3
ATE_FUN.1 CC Part 3
ATE_IND.2 CC Part 3
AVA AVA_VAN.3 CC Part 3
6.4 Security Assurance Requirements Rationale
The basis for the justification of EAL4 is the threat environment experienced by the typical
consumers of the TOE. This matches the package description for EAL4.
In addition, the evaluation assurance level has been augmented with ALC_FLR.2
commensurate with the flaw remediation capabilities offered by the developer beyond those
required by the evaluation assurance level.
7 TOE Summary Specification
7.1 TOE Security Functionality
The following section explains how the security functions are implemented. The different
TOE security functions cover the various SFR classes.
The primary security features of the TOE are:
• Cryptographic primitives
• Certificate generation
• Establishment and maintenance of TLS protected links
• Identification, authentication and authorization
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7.1.1 Cryptographic primitives
The TOE implements the TLSv1.1 as well as TLSv1.2 protocols as specified in the
respective RFC. The product does not use third party classes to provide this functionality. All
cryptographic primitives required by the protocols as well as other services in the TOE are
fully implemented in the TOE, including:
• generation of symmetric keys, including cryptographic sensitive parameters for
HMACs, the TLS handshake (such as pre-master secret), padding for RSA and the
generation of HTTP session cookies;
• verification of RSA keys and certificates;
• deterministic random number generator seeded by noise sources developed by HOB
and operational on all underlying systems allowed by this ST.
The “HOBLink Secure, Client” module within the HOBLink JWT component reflects the
“client” as specified in TLS and the HOB WebSecureProxy (WSP) component that includes
the “HOBLink Secure, Server” module implements the “server” as specified in TLS.
Any key material and cryptographically sensitive parameters are zeroized after use.
This functionality covers the SFRs of: FCS_CKM.1(RNG), FCS_CKM.4, FCS_COP.1(CERT),
FCS_RNG.1.
7.1.1.1 General characteristics of the TLS protocol
The first phase within the TLS protocol is the handshake protocol, in which a cryptographic
cipher suite (consisting of an asymmetric algorithm, a bulk data encryption algorithm, the key
size for the bulk data encryption algorithm, a hash algorithm) and cryptographic keys
(encryption/decryption keys, MAC secrets) are negotiated. Separate bulk data encryption
keys and MAC secrets are generated for each communication direction. The handshake
protocol uses MD5 and SHA-1 (TLSv1.1) and SHA-256 (TLSv1.2) to create these session
keys and MAC secrets. The MAC secrets are used for protecting integrity of the information
exchanged.
After the handshake protocol has been successfully completed, user data can be securely
transferred according to the agreed cipher suite. The TLS protocol ensures the confidentiality
and integrity of transmitted user data.
Integrity is achieved specifically by the HMAC mechanism for message authentication using
cryptographic hash functions in combination with the secret shared keys (MAC secrets).
Concealment of asymmetric encrypted secrets is achieved by adding random padding bytes.
A proper implementation of the TLS protocol allows detection of modification of data,
substitution of data, re-ordering of data, deletion of data, insertion of data, replay of data and
prevents disclosure of data.
This functionality covers the SFRs of: FCS_COP.1(TLS).
7.1.1.2 TLS implementation in the TOE
In the course of the handling of the TLS handshake protocol, the “HOBLink Secure, Client”
module within HOBLink JWT and the “HOBLink Secure, Server” module within the WSP
negotiate on (TLSv1.1: RSA, AES 128 bits, TLSv1.2: RSA, AES 128 bits) as the cipher suite.
These modules generate a TLS master secret out of the pre-master secret protected using
RSA encryption of 48 Bytes length from which keys used for AES and for MAC secrets using
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HMAC-SHA-1 or HMAC-SHA-256, respectively. User data is transferred only after a TLS
handshake has been successfully completed.
For the HTTPS connections, the TOE does not perform any certificate validation. The WSP
sends its server certificate to the web browser. The web browser together with the user is
assumed to correctly verify the WSP server certificate to prevent any man-in-the-middle
attacks and any derived attacks.
For the JWT connection, WSP again offers its server certificate to the HOBLink JWT
component. The HOBLink Client Security Unit holds all certificates needed for key chain
validation. Using the downloaded HOBLink Client Security Unit HOBLink JWT performs the
certificate verification, including the certificate chain validation.
This functionality covers the SFRs of: FCS_CKM.2, FCS_COP.1(CERT), FCS_COP.1(TLS).
7.1.2 Certificate Generation
The Security Manager component is able to generate RSA keys and issue X.509v3
certificates for these keys according to [RFC5280] with digital signatures based on the
properties documented in FCS_COP.1(CERT). In the evaluated configuration the Security
Manager generates RSA keys with a modulus size of 1536 bits or 2048 bits that are
constructed from random numbers proven to be prime. The implemented cryptographic key
generation algorithm is a slightly modified version of the algorithm defined in [FIPS186-3]
appendix B.3.3. Primality of the numbers used to create a RSA modulus is tested using the
Miller-Rabin test. The Miller-Rabin algorithm is implemented according to section C.3.1 of
[FIPS186-3] which equals the description of D.E. Knuth in [KNUT_CPRG_II] (Factoring into
primes, Algorithm P). It is also described in [ISO_IEC_18032] and [X9.31], and table C.3 of
[FIPS186-3] determines the test requirements, (also found in Annex A.3, table A.1 in
[ISO_IEC_18032]). [HboApplCryp] is used to verify the implemented algorithms against a
further source of information (p.139, p.165).
The RNG used for the generation of the RSA components is the Java implementation of the
same RNG algorithm used for the WSP.
This functionality covers the SFRs of: FCS_CKM.1(RSA), FCS_COP.1(CERT), FCS_RNG.1.
7.1.3 Establishment and maintenance of TLS protected links
The TOE requires that the client web browser initiates an HTTPS session based on TLSv1.1
or TLSv1.2 with the WSP component before any additional operation can proceed. If the web
browser fails to use the mentioned cryptographic protocols, WSP will terminate the
connection.
WSP also enforces the continued use of the HTTPS connection with the validation of the
HTTP session cookie (related to the user) when accessing protected web servers for each
access request. WSP decrypts the HTTPS requests and forwards these as HTTP requests
to the intended web server.
To initiate a session with a protected Remote Desktop server, the client web browser
together with its JVM is instructed to download the HOBLink JWT Java Webstart application
using an HTTPS connection to the given destination address (of the WSP) while presenting
the HTTPS session cookie. The HOBLink JWT Java Webstart application is started using the
parameters given in the HOBLink JWT Java Webstart file presented at the link of the
Remote Desktop server. The HOBLink JWT Java Webstart file contains all necessary
parameters. WSP now waits for a new TLS session to be initiated by HOBLink JWT. The
HOBLink JWT application initiates the TLS handshake and performs the server certificate
verification with the rules as defined in FDP_IFF.1(JWT) and assures that any subsequent
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RDP data exchanged with the accessed Remote Desktop server is routed through the newly
instantiated TLS link.
A TLS channel is established after all certificate validation passed successfully. Without a
HOBLink Client Security Unit, a TLS channel cannot be established.
This functionality covers the SFRs of:
• JWT: FDP_IFC.1(JWT), FDP_IFF.1(JWT), FDP_ITT.1, FDP_ITT.3,
FMT_CFG.2(JWT);
• HTTPS: FDP_IFC.1(HTTPS), FDP_IFF.1(HTTPS), FMT_CFG.2(HTTPS),
FTP_ITC.1.
7.1.4 Identification, authentication and authorization
WSP implements a gateway to the protected resources of web servers and Remote Desktop
servers. Before users are allowed to connect to these servers, WSP requires the user to
supply a username and password. These credentials are used to perform an LDAP-bind
operation to verify these credentials. If the LDAP server rejects the LDAP-bind operation with
these credentials, WSP also rejects the user. Otherwise the user is identified and
authenticated.
If the user is successfully identified and authenticated, the WSP retrieves the JWT and WSG
configuration for the logged-in user. In the next step the integrated web server in the HTTP
Handler module within the WSP generates a start web page for the logged-in user. The start
web page includes the links to the protected destination servers that the user is allowed to
access. Every link leads to one accessible server either with HOBLink JWT for an RDP
session or with the browser for web servers. The list of links to web servers is determined by
the user's configuration, but can be restricted by target filter entries in the WSP configuration
file. The WSP configuration file that is stored in a folder of the RD VPN installation is
configured by an authorized administrator.
A user now can access the destination servers via the links on the start web page. All
authorization relevant constraints that are active for access security are performed by the
WSP and determined in the WSP configuration based on role-based access control rules
specified in an access control list. Any communication established by selecting these URLs
always implies that the WSP is used as a gateway. Thus, the WSP is able to enforce the
configured authorization based on:
• the HTTP session cookies to be delivered by the client web browser with each
HTTPS request;
• the HTTP session cookies to be delivered by HOBLink JWT in a TLS connection that
subsequently is used for transporting RDP data of one Remote Desktop session to
one Remote Desktop server and back.
The administrator is able to configure the access control list to specify which role is granted
access to what resource. Moreover, the assignment of users to roles can be configured by
administrators as well.
This functionality covers the SFRs of: FDP_IFC.2, FDP_IFF.1(WSP), FIA_ATD.1,
FIA_UAU.1, FIA_UID.1, FIA_USB.1, FMT_CFG.2(WSP), FMT_CFG.1.
7.1.4.1 HTTP session cookies
After the user is identified and authenticated, the HTTP handler within the WSP issues an
HTTP session cookie. The web browser must submit this cookie with each HTTPS request.
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The WSP uses the cookie to accept further connections initiated and established by the user
or, by the user's activities, to prevent repetitive re-authentication by the user.
If a client does not submit a valid HTTP cookie, the request is denied.
HOBLink JWT receives all necessary parameters from the Webstart file the web start page
links to when it starts. The HOBLink JWT component submits information of the HTTP
session cookie after the successful establishment of the TLS connection to allow WSP to link
the new TLS connection with the already authenticated user. The WSP forwards the
connection data to the selected Remote Desktop server.
This functionality covers the SFRs of: FCS_RNG.1, FIA_ATD.1, FIA_USB.1.
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8 Conventions, Terminology, and Acronyms
This section identifies the formatting conventions used to convey additional information,
specific terminology and acronyms used throughout the remainder of the document.
8.1 Terminology
Application Connectivity software product, more specifically either
HOBLink JWT (RDP connection) or a Web Browser
(HTTP connection) that transfers user data between
one computer (Client) and another (Server).
Attacker An unauthorized user who attempts to violate the TSP.
Remote Desktop Server A software product for servers that allow multiple
users to log on simultaneously to a server system that
provides sessions for remote desktop clients, sharing
the hardware and software resources of the server.
TLS A common denominator for the TLS protocol 1.1 and
1.2 as specified in [TLS] (for example Microsoft
Windows Remote Desktop Session Host).
User Any entity (human user or external IT entity) outside
the TOE that interacts with the TOE.
User Data Data created by and for the user, that does not affect
the operation of the TSF. User data which is
transferred over physically separated parts of the TOE
according to the TSP is referred to as “transmitted
information”.
TOE Security Policy A set of rules that regulate how assets are managed,
protected and distributed within a TOE.
Web Browser Software product for Users that requests data from
Web Servers using HTTP or HTTPS and displays the
information with a GUI.
Web Server Software product for servers that sends files via HTTP
or HTTPS based on requests sent by Web Browsers.
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9 Index of Tables and Illustrations
Tables and Illustrations
Table 1: Hardware and Software requirements.......................................................................8
Table 2: JVMs that are currently used for the HOBLink Security Manager..............................8
Table 3: JVMs allowed to be used with HOBLink JWT............................................................9
Fig. 1: Overview of HOB RD VPN scenario...........................................................................11
Table 4: Software components of the TOE............................................................................14
Table 5: Threats to be countered by the TOE........................................................................18
Table 6: Assumptions to be covered by physical constraints.................................................18
Table 7: Assumptions to be covered by personnel constraints..............................................18
Table 8: Assumptions to be covered by procedural constraints.............................................19
Table 9: Assumptions to be covered by connectivity constraints...........................................19
Table 10: Organizational Security Policies to be met by the TOE..........................................20
Table 11: Security Objectives for the TOE.............................................................................20
Table 12: Security Objectives for the TOE environment........................................................21
Table 13: Mapping of security objectives to threats and policies...........................................22
Table 14: Mapping of security objectives for the Operational Environment to assumptions,
threats and policies................................................................................................................23
Table 15: Sufficiency of objectives countering threats...........................................................23
Table 16: Sufficiency of objectives holding assumptions.......................................................24
Table 17: Sufficiency of objectives enforcing Organizational Security Policies......................27
Table 18: Security functional requirements for the TOE........................................................29
Table 19: Mapping of security functional requirements to security objectives........................44
Table 20: Security objectives for the TOE rationale...............................................................45
Table 21: TOE SFR dependency analysis.............................................................................46
Table 22: Security assurance requirements...........................................................................48
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10 Related standards and documents
[BASE64] RFC 1521: Mechanisms for Specifying and Describing the Format of
Internet Message Bodies, September 1993
[CC] Common Criteria for Information Technology Security Evaluation, Version
3.1, Revision 4, September 2012, Parts 1 through 3
[DER] See ITU-T Recommendation X.690 (2002) | ISO/IEC 8825-1:2002,
Information Technology - ASN.1 Encoding Rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and
Distinguished Encoding Rules (DER)
[FIPS180] FIPS PUB 180-4, Federal Information Processing Standard,
Secure Hash Standard (SHS), March 2012, available at
http://csrc.nist.gov/publications/fips/fips180-4/fips-180-4.pdf
[FIPS186-3] FIPS PUB 186-3, Federal Information Processing Standard,
Dignature Signature Standard (DSS), June 2009, available at
http://csrc.nist.gov/publications/fips/fips186-3/fips_186-3.pdf
[FIPS197] Federal Information Processing Standards Publication 197, ADVANCED
ENCRYPTION STANDARD (AES), November 26, 2001
available at http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf
[HboApplCryp] Handbook of Applied Cryptography
Alfred J. Menezes, Paul C. van Oorschot, Scott A. Vanstone
CRC Press LLC, Florida, USA, 1997
[HTTP] RFC 2616, Hypertext Transfer Protocol, HTTP/1.1 (update to RFC 2068),
June 1999
[HTTPS] RFC 2818, E. Rescorla, HTTP over TLS, May 2000,
see also [RFC2246]
[ISO_IEC_18032] International Standard ISO/IEC 18032, First edition, 2005-01-15,
Information technology – Security techniques – Prime number generation,
Geneva, Switzerland 2005
[KNUT_CPRG_II] The Art of Computer Programming, Volume II, Seminumerical Algorithms,
3rd Edition, Donald E. Knuth, Addison Wesley Longman, USA 1998
[KS2011] Bundesamt für Sicherheit in der Informationstechnik
Proposal for functionality classes for random number generators,
Version 2.0, 2011-09-18
[PKCS1] PKCS #1 v2.1: RSA Cryptography Standard, RSA Laboratories,
June 14, 2002
see also
RFC 3447, Public-Key Cryptography Standards (PKCS) #1:
RSA Cryptography Specifications, Version 2.1, RSA Laboratories,
February 2003
[PKCS5] PKCS #5 v2.1, Password-Based Cryptography Standard,
RSA Laboratories, October 5, 2006
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[PKCS7] PKCS #7: Cryptographic Message Syntax Standard, Version 1.5,
RSA Laboratories, Revised November 1, 1993
available at ftp://ftp.rsasecurity.com/pub/pkcs/doc/pkcs-7.doc
[PKCS12] PKCS 12 v1.0: Personal Information Exchange Syntax,
RSA Laboratories, June 24, 1999, available at
ftp://ftp.rsasecurity.com/pub/pkcs/pkcs-12/pkcs-12v1.pdf
[RFC1321] Request for Comments: 1321, The MD5 Message-Digest Algorithm,
April 1992
[RFC2104] Request for Comments: 2104, HMAC: Keyed-Hashing for Message
Authentication, February 1997
[RFC4346] Request for Comments: 4346, The Transport Layer Security (TLS)
Protocol Version 1.1, April 2006
[RFC4510] Request for Comments: 4510, Lightweight Directory Access Protocol
(LDAP): Technical Specification Road Map, June 2006
[RFC5246] Request for Comments: 5246, The Transport Layer Security (TLS)
Protocol Version 1.2, August 2008
[RFC5280] Request for Comments: 5280, Internet X.509 Public Key Infrastructure
Certificate and Certificate Revocation List (CRL) Profile, May 2008
[SP800-38A] NIST Special Publication 800-38A, 2001 Edition
Recommendation for Block Cipher Modes of Operation
[SP800-90A] NIST Special Publication 800-90A (A Revision of SP 800-90),
Recommendation for Random Number Generation Using Deterministic
Random Bit Generators, January 2012
[X9.31] X9.31 - 1998, Digital Signatures Using Reversible Public Key
Cryptography ..., American National Standard for Financial Services,
American National Standards Institute, September 9, 1998
[XML] See “W3C Recommendation 04 February 2004, edited in place 15 April
2004“, available at http://www.w3.org/TR/xml11/
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11 Appendix/Appendices
Additional documentation texts and references that are related to the above given
description.
11.1 Appendix A: Overview of HOB RD VPN scenario
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Remote
Desktop
Server
Web
Secure
Proxy
Gateway Server
HL
Secure,
Server
Client
Computer
System
Web
Server
Server
Security
Unit
Client
Security
Unit
HL
JWT
package
WSP
configuration
tool
Web
Browser
HOBLink
JWT
HL
Secure,
Client
LDAP
database
LDAP Server
HL
Security
Manager
Administrative
Workstation
client
configuration
tool
for
LDAP-based
user
administration
HL
Secure,
Client
HTTP
Handler
JAVA
runtime
environment