CROSS-REFERENCE TO RELATED APPLICATIONSThe present application is a continuation and claims the priority benefit of U.S. patent application Ser. No. 13/481,742 filed May 25, 2012, the disclosure of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION1. Technical Field
Various inventive embodiments disclosed herein relate generally to computer security applications. In particular, embodiments disclosed herein relate to a system for and methods of providing single sign-on (SSO) capability in an application publishing environment.
2. Background
In a client-server computing system, a computer application or program that is running on one computer (i.e., the server) may be accessible to another computer (i.e., the client) over a network, such as over the Internet. The user interface running on the server is exposed and visible to the client. In this way, the client has remote access to the server and the user of the client device can interact with the application that is running on the server. Single sign-on (SSO) capability is a feature that may be beneficial in client-server computing systems. SSO is a method of access control that enables a user to log in once and gain access to the resources of multiple software systems without being prompted to log in again.
In certain client-server computing systems, a web application is used as the gateway into the system. Namely, a web component that is accessible via the Internet is used as the gateway that controls access to the host and to resources installed and running thereon. Using the web application, the user authenticates to the gateway server. If, for example, the gateway server is implemented as an operating system (OS)-specific application, the user authenticates to that OS-specific application. In this example, the OS-specific application may include mechanisms by which the OS may share the user's security context and automatically authenticate the user on other computers that are members of the same domain. However, a drawback of these single sign-on mechanisms is that they do not necessarily work well between a web application and the OS-specific application. Namely, there is no protocol to share user security context between a web application and the OS-specific application. As a result, this scenario will require the user to sign into the web application and then sign in again to access the OS-specific application.
BRIEF DESCRIPTION OF THE DRAWINGSVarious inventive embodiments disclosed herein, both as to its organization and manner of operation, together with further objectives and advantages, may be best understood by reference to the following description, taken in connection with the accompanying drawings as set forth below:
FIG. 1 illustrates a block diagram of a client-server computing system for providing single sign-on capability in an application publishing environment, according to the present disclosure;
FIG. 2 illustrates a flow diagram of a method of registering a computer on a computer cluster of the client-server computing system, according to the present disclosure;
FIG. 3 illustrates a flow diagram of a method of bringing a host computer online within the computer cluster of the client-server computing system, according to the present disclosure;
FIG. 4 illustrates a flow diagram of a method of performing computer cluster authentication, according to the present disclosure;
FIGS. 5 and 6 illustrate a flow diagram of a method of performing resource authentication without the need for a user to reenter his/her credentials, according to the present disclosure; and
FIG. 7 illustrates a flow diagram of a method of processing a single sign-on (SSO) failure, according to the present disclosure.
DETAILED DESCRIPTIONThe disclosure is a system for and methods of providing single sign-on (SSO) capability in an application publishing environment. Namely, the system and methods allow users to enter credentials one time and then access resources that may be distributed across multiple computers with no further prompting of the user for credentials. The system and methods of the disclosure exhibit numerous advantages over existing systems. In various embodiments, the system and methods provide SSO capability in distributed application environments in which a web application is used as the gateway into the system. Further, the system and methods of the disclosure allow users to sign into a web application and then allow users to authenticate to a native application, such as a native Windows application, on the same directory without reentering credentials, such as username and password.
An SSO method of the disclosure includes performing a computer cluster authentication process in which a user enters his/her credentials followed by a resource authentication process in which there is no need for the user to reenter his/her credentials, having entered them already in the computer cluster authentication process.
FIG. 1 illustrates a block diagram of a client-server computing system100 for providing single sign-on capability in an application publishing environment. Client-server computing system100 includes a computer cluster105 for hosting certain resources, applications, programs, processes, files, and/or data that are published to users who are accessing computer cluster105 remotely. In one example, computer cluster105 includes a network of one ormore host computers110, i.e., host computers110-1 through110-n; agateway server120; agateway service database130; and a user database140. Host computers110-1 through110-nmay be connected togateway server120 and user database140 via, for example, a TCP connection. The TCP connection may be a standard TCP connection with no encryption or a TCP connection with encryption. One or more users150 are associated with client-server computing system100. Users150 may be individual users and/or groups of users and, thus, hereafter it may be understood that any reference to users150 means individual users or user groups (i.e., groups of users150).
Users150 may access the resources, applications, programs, processes, files, and/or data of computer cluster105 viaclient devices160, which are connected to computer cluster105 via anetwork170.Client devices160 may be any remote access computing device, such as, but not limited to, any handheld computing device, mobile phone, tablet device, laptop computer, desktop computer, and the like.Network170 may be, for example, a local area network (LAN) and/or a wide area network (WAN) for connecting to the Internet. Entities of client-server computing system100 may connect tonetwork170 by any wired and/or wireless means. Client-server computing system100 may be implemented using standard client-server architecture between computer cluster105 andclient devices160.
Eachhost computer110 is a computer on which resources, files, applications, programs, and/or processes run on behalf of a given user150. For example, in a remote access system, such as client-server computing system100, the “remoting” software is installed and executing (i.e., “running”) on eachhost computer110, which is software that allows users150 to remotely access resources, files, applications, programs, and/or processes that are running on eachhost computer110. By way of example, a set ofresources112 is installed and running on eachhost computer110. Individual instances and/or type of resources, applications, programs, processes, files, and/or data on eachhost computer110 is represented by resources112-1 to112-n. Examples ofindividual resources112 may include, but are not limited to, a word processing application, such as Microsoft® Word; a personal or business finance application, such as Intuit® QuickBooks®; a computer-aided design (CAD) application, such as Autodesk® AutoCAD® and Cadence® Virtuoso®; a medical clinical workflow application, such as Siemens AG Symbia.net™.
Using an example of three host computers110-1,110-2, and110-3, instances of the same or different types ofresources112 may be installed and running on each of the host computers110-1,110-2, and110-3. For example, Microsoft® Word maybe on installed and running on all three host computers110-1,110-2, and110-3. Intuit® QuickBooks® maybe on installed and running on host computers110-2 and110-3, but not on host computer110-1. Autodesk® AutoCAD® maybe on installed and running only on host computer110-2. Siemens AG Symbia.net™ maybe on installed and running on host computers110-1 and110-3, but not on host computer110-2, and so on.
Eachhost computer110 further includes ahost service116.Host service116 is the application or process that manages the user authentication process at thehost computer110 whenever a resource access request is received from aclient device160 of a certain user150 viagateway server120. Additionally,host service116 provides an application publishing service. Namely, at eachhost computer110,host service116 is used to publish its resources112-1 to112-nto users150. Thehost service116 is an application running on eachhost computer110 that is capable of starting a remote session in which applications can be run and displayed to a user150 atclient device160, which is a remote device. Thehost service116 application manages the communication of eachhost computer110 with theclient device160 with respect to creating and displaying host sessions on behalf of users150.
Gateway server120 is used as the gateway into computer cluster105. Namely,gateway server120 provides the interface betweenclient devices160 andhost computers110. As such, resources112-1 to112-nof host computers110-1 through110-nis delivered toclient devices160 viagateway server120. More specifically,gateway server120 includes agateway service122.Gateway service122 is implemented as a web application that is accessible byclient devices160 via, for example, the Internet (e.g., network170).Gateway service122 controls access tohost computers110 and any other entities of computer cluster105. More particularly, under the control ofgateway service122,resources112 ofhost computers110 shall be visible to and accessible byclient devices160 vianetwork170. For example, users150 authenticate togateway server120 usinggateway service122, which is a web application. Once authenticated, based on access rights and permissions, users150 are allowed access to resources112-1 to112-nof host computers110-1 through110-nthat are connected togateway server120.
In one embodiment, computer cluster105 is a network of computers that are members of the same domain or directory. Namely,host computers110 andgateway server120 are members of the same domain or directory. In another embodiment,host computers110 andgateway server120 may be members of different domains or directories as long as the user directory can be accessed from all the computers. For example, if trust relationships exist between the domains.
Aclient application162 is an application installed on and executing on eachclient device160.Client application162 provides a user interface togateway service122 ofgateway server120. Namely,client application162 is the component that is the counterpart togateway service122 ofgateway server120.Client application162 may be implemented as a web application and run in a web browser, such as Internet Explorer. However,client application162 may be implemented by other means, such as a .NET application, a light weight desktop application, a mobile app, and the like.
Gateway service122 ofgateway server120 is the first process thatclient application162 ofclient devices160 connects to. The purpose ofgateway service122 is to authenticate users150 and keep track of what each individual user150 is allowed to access. Namely,gateway service122 is used to enforce the access rights and limitations that a system administrator (not shown) has defined.Gateway server120 stores its own information in agateway service database130.
Gateway service database130 is used for storing access information. For example, the identity of eachhost computer110 that a given user150 is allowed to access is stored ongateway service database130. Optionally, user/group account information and user/group credentials may be stored ingateway service database130. However, typically user/group account information and user/group credentials are stored in a separate user database140, which is accessible togateway server120 and allhost computers110, but is generally not accessible toclient devices160. For example, user/group information142 may be stored in user database140. A system administrator (not shown) creates and defines user/group information142. User/group information142 may contain, for example, account information, user names, group names, user credentials, locations of user/group profiles (e.g., file paths), and the like.
Client-server computing system100, and more particularly computer cluster105, may support a cloud computing environment. In a cloud computing environment,gateway server120 is the cloud server. Further, computer cluster105 of client-server computing system100 is not limited to onegateway server120 only. Computer cluster105 may include any number of gateway servers120 (or cloud servers).
A user table132, a user session table134, and an access control table136 are also stored ingateway service database130. User table132 contains a list of all users150 (or groups) that are currently signed intogateway service122 as well as any users150 (or groups) that have signed intogateway service122 in the past. User table132 is typically populated on demand, as needed. For example, once a user150 signs in and is authenticated withgateway service122, a record is created in user table132. Additionally, a system administrator may create records in user table132 and may also choose to purge user table132 at certain times. In this way, user table132 may contain a partial list of the users in user database140. Each record in user table132 contains, for example, the name or other identifying information of a certain user150 (or group), as well at the user's access rights.
User session table134 contains a list of sessions of signed-in users150. Namely, each time a user150 signs intogateway service122, a session object is created and stored in user session table134. The session object is removed from user session table134 when the user150 signs out or when the session times out. Access control table136 that contains the mapping between resources (e.g.,resources112 of host computers110) that are managed bygateway service122 and users150 (or groups) that are allowed to access these resources.
Further, a host table138 atgateway service database130 contains a list of allhost computers110 that are registered withgateway server120. Accordingly, a record for each of thehost computers110 is stored in host table138. Each record in host table138 contains, for example, the hostname or host ID and network address. Each record may also include a hardware identifier, such as a media access control (MAC) address, for thecertain host computer110. A public security certificate or public encryption key (PUBLIC KEY) exists for each of thehost computers110. The record in host table138 for each of thehost computers110 contains its PUBLIC KEY. Additionally, a private encryption key (PRIVATE KEY) exists at each of thehost computers110. The PRIVATE KEY is a secret key for each of thehost computers110 in computer cluster105. The PRIVATE KEY allows each member of computer cluster105 to encrypt and decrypt passwords. More details of creating and installing the PUBLIC KEYS and PRIVATE KEYS in computer cluster105 are described with reference toFIG. 2.
Eachgateway service122 orgateway server120 must have the capability to encrypt passwords, and eachhost service116 ofhost computers110 in computer cluster105 must have the capability to decrypt passwords. Eachhost service116 of host computers100 may also have the ability to encrypt passwords. For example,gateway service122 ofgateway server120 encrypts a password and then passes the encrypted password to acertain host computer110.Host service116 of thehost computer110 then decrypts the encrypted password. In another example,host service116 of thehost computer110 encrypts a password and stores it ingateway service database130 and, at a later time, accesses and decrypts the password to authenticate a user150. An encryption algorithm (not shown) that is used to perform the encryption and decryption is running on each computer in computer cluster105. An example of an encryption algorithm is the RSA encryption algorithm (RSA is the Security Division of EMC Corporation (Bedford, Mass.)).
In operation, a system administrator sets up and controls theresources112 andhost computers110 that each user150 (or group) may access. User and group information is stored in the user database140. Optionally, user and group information is stored in a separate database, such as in an active directory database (not shown) or ingateway service database130.
A user150 accesses computer cluster105 via his/herclient device160. For example, using a web browser ofclient device160, user150 may initiateclient application162. In so doing,client device160 connects togateway service122 ofgateway server120. Using the web browser,client application162 prompts the user150 to enter his/her credentials. For example, the user150 is prompted to enter a username and password. Having entered the correct username and password, the user150 is authenticated and connected to computer cluster105 and has access to resources therein based on access rights and permissions that have been previously determined and stored in the user/group information142 of the specific user150. More details of a method of performing computer cluster authentication are described with reference toFIG. 4.
Upon the successful authentication of the user150 onto computer cluster105,gateway service122 ofgateway server120 immediately reuses the credentials of user150 and authenticates user150 on one of thehost computers110 of computer cluster150.Gateway service122 then erases from memory the credentials of user150. Next, anyresource112 that has been published to user150 is displayed to the user150 viaclient application162 andgateway service122 ofgateway server120. Next, user150 attempts to access or view acertain resource112, such as Microsoft® Word, within computer cluster105.Gateway service122 ofgateway server120 determines on which one or more of thehost computers110 the Microsoft® Word application resides and directs the access request to a certain one of thehost computers110. Then, a process of resource authentication is performed usinghost service116 of the givenhost computer110 and usinggateway service122 ofgateway server120, wherein the user150 is authenticated to thehost computer110 without being prompted to reenter his/her credentials. In this way, a single sign-on function is accomplished within computer cluster105 of client-server computing system100, which is the application publishing environment.
By contrast, a drawback of conventional systems is that they either a) require a user to enter his/her credentials when first accessing the computer cluster, and then they require the user to reenter credentials each time a resource on a certain host is accessed or b) require a user to cache his/her credentials in a database or file and thereby create a security vulnerability. More details of a method of performing resource authentication without the need for a user to reenter his/her credentials are described with reference toFIGS. 5 and 6.
FIG. 2 illustrates a flow diagram of amethod200 of registering ahost computer110 on computer cluster105 of client-server computing system100. In order to allow access to anyhost computer110 usinggateway service122, each of thehost computers110 is registered withgateway service122 when itshost service116 is installed. In so doing, eachhost computer110 must identify itself togateway service122 and establish credentials by which it may connect togateway service122. In this way, it is reliably ensured that thehost computer110 is connected togateway service122 and vice versa. Accordingly, with respect to the SSO aspect of the disclosure,method200 provides a means by which anyhost computer110 andgateway service122 can reliable identify each other. Further,method200 is used to generate and store the encryptions keys, which are used to exchange credentials (e.g., username and password) during the SSO process. The encryptions keys are critical to maintaining the integrity of the SSO process.Method200 may include, but is not limited to, the following steps.
Atstep210, a host registration or setup program (not shown) of a givenhost computer110 establishes a secure connection togateway service122 ofgateway server120. For example, the secure connection may be a secure sockets layer (SSL) connection. In this example,gateway service122 has an SSL certificate installed thereon that identifies the service. The SSL certificate is the means by which thehost service116 of thecertain host computer110 is ensured it is communicating withgateway service122 ofgateway server120 and not some other service.
Atstep212, a system administrator authenticates togateway service122 using an account that has rights to registerhost computers110 withgateway service122. More specifically, aftergateway service122 identifies itself to the system administrator using its SSL certificate atstep210, the system administrator that has rights to register thehost computer110 enters his/her credentials (e.g., username and password), thereby identifying himself/herself togateway service122.
Atstep214, the host registration or setup program (not shown) of thecertain host computer110 transmits information that identifies thehost computer110 togateway service122 ofgateway server120. This information may include, for example, the hostname, network address, and MAC address of thehost computer110, which uniquely identifies thehost computer110. This information is stored in host table138 and is used in host authentication processes, such as the process described with reference toFIG. 3.
Atstep216,gateway service122 generates the public and private encryption keys (i.e., PUBLIC KEY and PRIVATE KEY) for thehost computer110. For example, the PUBLIC KEY and PRIVATE KEY may be generated as SSL certificates.Gateway service122 is a certificate authority, which allows it to generate public and private encryption keys for anyhost computer110 connecting thereto. As such, during any host authentication process (seeFIG. 4),gateway service122 can verify that the SSL certificate from thehost computer110 was generated bygateway service122. Optionally,gateway service122 may accept certificates from other certificate authorities.
Atstep218,gateway service122 creates a host record in host table138 ofgateway service database130. Stored in this record is a unique identifier for the host (a host ID), the host information (e.g., hostname, network address, and MAC address) provided instep214, as well at the PUBLIC KEY generated instep216.
Atstep220,gateway service122 returns the PUBLIC KEY and PRIVATE KEY, along with the host ID, to thehost computer110.
Atstep222, the host registration or setup program (not shown) of thecertain host computer110 stores the PUBLIC KEY and PRIVATE KEY in a secure location on thehost computer110. For example, the PUBLIC KEY and PRIVATE KEY are stored in a directory of thehost computer110 that only a system administrator can access. In addition, the host ID is stored on thehost computer110.
FIG. 3 illustrates a flow diagram of amethod300 of bringing ahost computer110 online within computer cluster105 of client-server computing system100. By way of example, in the steps ofmethod200, host computer110-2 is the host computer of interest.Method300 may include, but is not limited to, the following steps.
Atstep310,host service116 of host computer110-2 starts and connects togateway service122 ofgateway server120. The connection togateway service122 may be, for example, an SSL connection or a TCP connection.
Atstep312,host service116 of host computer110-2 transmits the host ID, host-specific information and its PUBLIC KEY togateway service122, thereby providing unique identifying information togateway service122. For example,host service116 transmits the hostname and/or host ID, network address, and MAC address of host computer110-2 along with the PUBLIC KEY of host computer110-2 togateway service122.
Atstep314,gateway service122 queries host table138 ofgateway service database130 for the host record that corresponds to host computer110-2.
Atstep316,gateway service122 authenticates host computer110-2 by comparing the information received instep312 with information stored in host table138 ofgateway service database130. For example,gateway service122 compares the hostname or host ID, network address, MAC address, and PUBLIC KEY received instep312 to the information about host computer110-2 that is stored in host table138.Gateway service122 also verifies that the PUBLIC KEY was issued by a trusted certificate authority.
Atdecision step318,gateway service122 determines whether the information received instep312 matches the information about host computer110-2 that is stored in host table138 ofgateway service database130. If the information matches,method200 proceeds to step320. However, if the information does not match,method200 proceeds to step322.
Atstep320,gateway service122 accepts the connection and host computer110-2 is connected togateway service122 ofgateway server120. Once connected, host computer110-2 is online within computer cluster105 and itsresources112 are visible to users150.
Atstep322,gateway service122 rejects the connection and host computer110-2 is not online within computer cluster105. Consequently, host computer110-2 and itsresources112 are not visible to users150. Optionally, if the connection fails,method300 may return to step310 andhost service116 of host computer110-2 tries again to connect.
FIG. 4 illustrates a flow diagram of amethod400 of initiating computer cluster authentication; namely, of initiating the SSO process.Method400 may include, but is not limited to, the following steps.
Atstep410,client application162 ofclient device160 connects togateway service122 ofgateway server120. For example, a particular user150 starts upclient application162 on his/herclient device160. Using a web browser, the user150 enters the address (e.g., URL, IP address, a name that resolves to the IP address, etc) ofgateway server120 and opens a secure (e.g., SSL) connection togateway server120. If using a desktop application, the connection may be automatically established togateway server120 when the application is started. In any case,gateway service122 ofgateway server120 is exposed toclient device160 viaclient application162. In the case ofmultiple gateway servers120, there may be a load balancer to balance the connection to any one of thegateway servers120.
Atstep412, once the connection is established,client application162 prompts user150 for credentials. For example, if the user150 is connected using a web browser, the browser loads in the sign-on application fromgateway server120. The sign-on application prompts the user150 for his/her credentials, such as a username and password. If the user150 is connected using a desktop application installed onclient device160, the desktop application may automatically establish the connection and then prompt the user150 for username and password.
Computer cluster105 of the disclosure is not limited to a particular form of credentials. A username and password is just one example. Other authentication inputs may be used. For example, a multi-step process may be used, such as enter username and password, then prompt for a personal identification number (PIN); or enter username and password, thengateway server120 transmits an SMS to the user150's cell phone that includes a PIN# that the user150 subsequently enters.
Atstep414, usingclient application162 ofclient device160, the user150 enters his/her computer cluster105 credentials, such as his/her username and password.
Atstep416,client application162 ofclient device160 transmits the credentials togateway service122 ofgateway server120.
Atstep418,gateway service122 authenticates user150 against information in user database140 or ingateway service database130. For example,gateway server120 calls to user database140 to authenticate the user150. However, ifgateway service122 is configured to usegateway service database130, the user150 is defined ingateway service database130 and, therefore,gateway service122 performs the authentication against the information ingateway service database130. For security reasons, a user's actual credentials, such as actual username and password, are not stored in any database. Instead, a hash value of the credentials is stored.
Atdecision step420, it is determined whether the computer cluster authentication is successful. Namely, whether the credentials entered by the user150 match the credentials for that user150 in user database140 or ingateway service database130. If the authentication is successful, thenmethod400 proceeds to step422. However, if the authentication fails, thenmethod400 proceeds to step434.
Atstep422,gateway service122 selects acertain host computer110. For example,gateway service122 selects ahost computer110 that has the lightest load (i.e. lowest CPU utilization) or selects thelast host computer110 that the user150 accessed in a previous session on the computer cluster105. In one example,gateway service122 selects host computer110-1.
Atstep424,gateway service122 encrypts the credentials the user150 entered instep414 using the PUBLIC KEY of the selectedhost computer110. Continuing the example,gateway service122 encrypts the credentials using the PUBLIC KEY of host computer110-1.Gateway service122 uses any standard encryption algorithm that is appropriate for encrypting sensitive data, such as the RSA encryption algorithm.
Atstep426,gateway service122 transmits the encrypted credentials to hostservice116 of the selectedhost computer110. Continuing the example,gateway service122 transmits the encrypted credentials to hostservice116 of host computer110-1. The transmission of the encrypted credentials may be, for example, over an SSL connection or TCP connection, both of which are suitably secure because the credentials can only be decrypted by an entity that has the PRIVATE KEY.
Atstep428,host service116 of the selectedhost computer110 decrypts the credentials of user150 and authenticates the user150 via information in user database140. Continuing the example,host service116 of host computer110-1 authenticates the user150 via information in user database140.
Atdecision step430, it is determined whether the host authentication is successful. Namely, whether the credentials user150 used to authenticate togateway service122 are acceptable tohost computer110. If the authentication is successful, thenmethod400 proceeds to step432. However, if the authentication fails, thenmethod400 proceeds to step436. Optionally, if the authentication fails, thenmethod400 proceeds to step434.
Atstep432,host service116 of the selectedhost computer110 starts a host session for the user150. Continuing the example,host service116 of host computer110-1 starts a host session for the user150. The result is an identified session at host computer110-1 in which the user150 is authenticated. Optionally, the host session that is started is only a partially constructed host session, in which certain processes may be deferred until actually needed.
Atstep434, the authentication failure is processed. In one example,client application162 ofclient device160 and/orgateway service122 notifies the user150 of an error and thenclient application162 is closed. In another example,client application162 and/orgateway service122 prompts user150 to try again to enter credentials that are valid on thehost computer110. For example,method400 may return to step414 and reiterate throughsteps414,416,418, and420. User150 may be allowed a certain number of attempts (e.g.,4 attempts) beforeclient application162 is closed.
Atstep436, the SSO failure is processed according to amethod700 ofFIG. 7, which is a method of processing a SSO failure.
FIGS. 5 and 6 illustrate a flow diagram of amethod500 of performing resource authentication without the need for a user150 to reenter his/her credentials, having entered them already in the computer cluster authentication process ofmethod400 ofFIG. 4. Further,method500 of performing resource authentication is iterated any time a user150 accesses a host computer100 that is different from the host computer100 on which the user150 already has a session. For example, if in the process of the user150 accessing and/viewingcertain resources112, the host computers110-1,110-2, and110-3 are accessed, thenmethod400 iterates three times—once for host computer110-1, once for host computer110-2, and once for host computer110-3; all without the need for the user150 to reenter his/her credentials, having entered them already in the computer cluster authentication process ofmethod400 ofFIG. 4.Method500 may include, but is not limited to, the following steps.
Atstep506, a user150 attempts to access acertain resource112 residing on one ormore host computers110. For example, once the user150 is authenticated into computer cluster105 usingmethod400 ofFIG. 4, the user150 is presented with a list of specific resources112 (e.g., resources, applications, programs, processes, files, and/or data) to which he/she has access rights. From the list, the user150 selects acertain resource112. For example, the user150 selects Microsoft® Word.
Atdecision step508,gateway service122 ofgateway server120 tracks thehost computers110 on which thecertain resource112, such as Microsoft® Word, exists. If the selectedresource112 is exists on more than onehost computer110,gateway service122 first determines whether the selectedresource112 exists on thehost computer110 selected instep422 ofmethod400 ofFIG. 4, in which case a host session is already running on thishost computer110. For example, if host computer110-1 is selected instep422 ofmethod400 and the selectedresource112 exists on host computer110-1, thenmethod500 proceeds to step510. However, if host computer110-1 is selected instep422 ofmethod400 and the selectedresource112 does not exist on host computer110-1, thenmethod500 proceeds to step514.
Atstep510,gateway service122 ofgateway server120 transmits a resource access request tohost service116 of thehost computer110 that already has a host session running for the user150. For example, if the user150 already has a host session on host computer110-1, thengateway service122 transmits the request to access Microsoft® Word tohost service116 of host computer110-1.
Atstep512,host service116 opens requestedresource112. Continuing the example,host service116 of host computer110-1 opens Microsoft® Word on host computer110-1.
Atstep514,gateway service122 determines whichother host computers110 have the selected resource112 (e.g., Microsoft® Word) and selects one of them. For example,gateway service122 may select thehost computer110 that has the lowest CPU utilization. In one example, of themultiple computers110 on which Microsoft® Word exists, host computer110-2 has the lowest CPU utilization and, therefore,gateway service122 selects host computer110-2. Generally, users150 only seeresources112 and do not know on whichhost computer110 or host computers110 a given resource exists. Optionally, thehost computers110 themselves can be published to users150 and users150 may select acertain resource112 on aspecific host computer110.
Atdecision step516,gateway service122 ofgateway server120 determines whether a host session for the requesting user150 is already running on thehost computer110 selected instep514. For example, if host computer110-2 is selected instep514,gateway service122 ofgateway server120 determines whether a host session for the requesting user150 is already running on host computer110-2. If a host session is already running on the selectedhost computer110,method500 proceeds to step518. However, if a host session is not running on the selectedhost computer110,method500 proceeds to step522.
Atstep518,gateway service122 ofgateway server120 transmits a resource access request tohost service116 of thehost computer110 selected instep514. Continuing the example,gateway service122 transmits the request to access Microsoft® Word tohost service116 of host computer110-2.
Atstep520,host service116 of thehost computer110 selected instep514 opens requestedresource112. Continuing the example,host service116 of host computer110-2 opens Microsoft® Word on host computer110-2.
Atstep522,gateway service122 ofgateway server120 transmits the resource access request tohost service116 of thehost computer110 selected instep514 to start a host session for the authenticated user150. Continuing the example, to start a host session,gateway server120 transmits a session creation request tohost service116 of host computer110-2, which was selected instep514. The session creation request includes the username (or account name), but does not include the password.
Atstep524,host service116 of thehost computer110 selected instep514 transmits a SSO request back togateway service122 ofgateway server120. Continuing the example,host service116 of host computer110-2 transmits a SSO request back togateway service122 ofgateway server120.
Atstep526,gateway service122 ofgateway server120 verifies that the SSO request is in response to a valid host session creation request. For example,gateway service122 may generate a universally unique identifier (UUID) for the new session and transmit the UUID to thehost computer110 selected instep514. Continuing the example,gateway service122 may require the host computer110-2 to provide this UUID in the SSO request. Additionally,gateway service122 may timestamp the UUID and only accept SSO requests for a given UUID that are received within a specified timeout period.
Atstep decision528,gateway service122 ofgateway server120 determines whether a host session for the authenticated user150 is running on ahost computer110 other than thehost computer110 selected instep514, for example, other than host computer110-2. If yes,method500 proceeds to step530. However, if no, the SSO process has failed andmethod500 may proceed to step542.
Atstep530,gateway service122 forwards the SSO request to thehost computer110 on which the user150 is already authenticated. For example, if instep422 ofmethod400 the user150 is already authenticated on host computer110-1,gateway service122 forwards the SSO request to host computer110-1. The method of the disclosure uses the fact that the user150 is already authenticated on one host computer110 (e.g., host computer110-1) to now authenticate the user150 on a different host computer110 (e.g., host computer110-2) using, for example, a Security Support Provider Interface (SSPI) API.
At step532, using a platform-specific SSO method, user security information established atstep428 ofmethod400 ofFIG. 4 that is on thehost computer110 selected instep422 of method400 (e.g., host computer110-1) is used to authenticate user150 on thehost computer110 selected in step514 (e.g., host computer110-2). In one example, in a Windows environment, the SSO authentication process may use the SSPI function. During authentication,gateway service122 relays challenges and responses between thehost computer110 on which the user is already authenticated (e.g., host computer110-1 selected instep422 of method400) and thehost computer110 selected in step514 (e.g., host computer110-2).
Atstep decision534, it is determined whether the resource authentication is successful. For example, the success or failure of the authentication may be depend on the whether any system errors have occurred, such as errors from the SSPI function, system communication errors, and the like, If errors are present, the authentication may fail. Another reason for failure may be the detection of an unauthorized user attempting to spoof the system. If the authentication is successful, thenmethod500 proceeds to step536. However, if the authentication fails, thenmethod500 proceeds to step546.
Atstep536,host service116 of thehost computer110 selected in step514 (e.g., host computer110-2) creates a host session for the authenticated user150.
Atstep538,host service116 of thehost computer110 selected in step514 (e.g., host computer110-2) opens the requested resource112 (e.g., an application, such as Microsoft® Word). Theparticular resource112 is presented to the user150 atclient device160 viagateway service122 andclient application162.
Atstep540, the authentication failure is processed. In one example,host service116 of thehost computer110 selected in step514 (e.g., host computer110-2) and/orgateway service122 notifies the user150 of an error andmethod500 ends.
Atstep542, the SSO failure is processed according to amethod700 ofFIG. 7, which is a method of processing a SSO failure.
FIG. 7 illustrates a flow diagram of amethod700 of processing a SSO failure.Method700 may include, but is not limited to, the following steps.
Atstep710,gateway service122 returns a failure response tohost service116 of the requestinghost computer110.
Atstep712,host service116 ofrequest host computer110 determines (e.g., but checking an administrator-defined configuration file) if an alternative authentication method is allowed. If an alternative authentication method is allowed,method700 proceeds to step714. However, if an alternative authentication method is not allowed, thenmethod700 proceeds to step722.
Atstep714,host service116 of the requestinghost computer110 authenticates the requesting user150 by alternative means, such as by prompting user150 to enter his/her credentials (e.g., username and password) or using credentials that have been cached from a previous session, and the like.
Atstep decision716, it is determined whether the resource authentication is successful. For example, it is determined whether the requesting user150 entered a correct or incorrect password. If the authentication is successful, thenmethod700 proceeds to step718. However, if the authentication fails, thenmethod700 proceeds to step722.
Atstep718,host service116 of the requestinghost computer110 creates a host session for the authenticated user150.
Atstep720,host service116 of the requestinghost computer110 opens the requested resource112 (e.g., an application, such as Microsoft® Word). Theparticular resource112 is presented to the user150 atclient device160 viaclient application162.
Atstep722, the authentication failure is processed. In one example,host service116 of the requestinghost computer110 notifies the user150 of an error andmethod700 ends. Optimally, further attempts are made to authenticate the requesting user150 by alternative means by returning to step714.
Referring now toFIGS. 1 through 7, when a user150 wishes to exit computer cluster105 of client-server computing system100, the user150 signs out ofgateway service122 ofgateway server120. For example, usingclient application162, which may be launched in a web browser on his/herclient device160, the user150 selects certain logout controls (e.g., click on a logout button). In so doing, the connection togateway server120 of computer cluster105 is closed. The user150 may then close the web browser on his/herclient device160. Alternatively, the user's session times out and the connection togateway server120 of computer cluster105 is automatically closed.
Once the user150 signs out ofgateway service122 or the user's session times out,gateway service122 ofgateway server120 deletes the user150's host sessions on allhost computers110. Optionally, the user150's host sessions may remain running so that the user150 can reconnect to them at a later time.
Various embodiments of the present invention allow for the method disclosed herein to be performed by an intermediary device (e.g., a cloud server), which may be associated with the host computer or reside elsewhere in the network (e.g., in the cloud). For example, a host computer of this disclosure may receive a request from a requesting client device, forward to a cloud server device, receive responsive data and forward to the client device, or visa-versa.