Patent Publication Number: US-2021194865-A1

Title: Using client certificates to communicate trusted information

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation application of, and claims priority to U.S. patent application Ser. No. 16/227,147 filed Dec. 20, 2018, which is a continuation of and claims priority to U.S. patent application Ser. No. 14/211,640 filed Mar. 14, 2014, which claims priority to U.S. Provisional Application No. 61/800,548 filed Mar. 15, 2013 by Derk Norton, et al., and titled “Method of Client Authentication,” each of which is incorporated by reference. 
     This application also incorporates by reference U.S. patent application Ser. No. 12/584,861 filed Sep. 14, 2009 by Edward R. Kelly, et al., and titled “Authentication System for Networked Computer Applications”; U.S. patent application Ser. No. 12/217,005 (now U.S. Pat. No. 8,291,490) filed Jun. 30, 2008 by Zahid N. Ahmed, et al., and titled “Tenant Life Cycle Management for a Software as a Service Platform”; U.S. patent application Ser. No. 11/533,296 (now U.S. Pat. No. 7,325,128) filed Sep. 19, 2006 by David L. Wood, et al., and titled “Log-On Service Providing Credential Level Change without Loss of Session Continuity”; U.S. patent application Ser. No. 11/224,675 (now U.S. Pat. No. 7,117,359) filed Sep. 12, 2005 by David L. Wood, et al.,” and titled “Default Credential Provisioning”; U.S. patent application Ser. No. 10/643,813 (now U.S. Pat. No. 6,944,761) filed Aug. 19, 2003 by David L. Wood, et al., and titled “Log-On Service Providing Credential Level Change without Loss of Session Continuity”; and U.S. patent application Ser. No. 10/431,097 filed May 7, 2003 by Derk D. Norton and titled “Client-Server Architecture Incorporating Secure Tuple Space.” 
    
    
     BACKGROUND 
     The disclosure generally relates to computer networks employing a client-server architecture and more particularly to authentication, authorization, and auditing within such networks. 
     Computer networks may employ various architectures. One such architecture is a client-server architecture. In a client-server network, a client, which may be an end user, may desire to use a service on an application server. Using a client application on the client, the client may send to the application server a request for the service. In reply, the application server may send to the client a response from the service or a resource associated with the service. A gateway server may be located between the client and the application server and may function as an interface between the client and the application server. The requests and responses may follow various protocols and require authentication and authorization. In addition, the application server may audit, or log, the requests and responses. 
     SUMMARY 
     In one embodiment, the disclosure includes a device comprising: a receiver configured to receive a client certificate; a processor coupled to the receiver and configured to: authenticate the client certificate, extract, in response to the authentication, attributes from the client certificate, and create, in response to the extraction, a message comprising reformatted attributes based on the attributes, wherein the reformatted attributes can be trusted; and a transmitter coupled to the processor and configured to transmit the message. 
     In another embodiment, the disclosure includes a device comprising: a processor configured to: process a client certificate comprising a certificate identifier (ID) attribute, a tenant ID attribute, and a role ID attribute, and package the client certificate in a request for a shared service; and a transmitter coupled to the processor and configured to transmit the request. 
     In yet another embodiment, the disclosure includes a method comprising: receiving a client certificate; authenticating the client certificate based on a signature in the client certificate; authorizing, in response to the authenticating, the client to access a shareable service; extracting, in response to the authenticating, attributes from the client certificate; and creating, in response to the extracting, a message comprising reformatted attributes based on the attributes, wherein the reformatted attributes can be trusted. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of a client-server network according to an embodiment of the disclosure. 
         FIG. 2 a    is a first portion of a message sequence diagram of the network described in  FIG. 1  according to an embodiment of the disclosure. 
         FIG. 2 b    is a second portion of a message sequence diagram of the network described in  FIG. 1  according to an embodiment of the disclosure. 
         FIG. 3  is a schematic diagram of the client certificate described in  FIGS. 2 a    and  2   b.    
         FIG. 4  is a flowchart illustrating a method of processing a client certificate according to an embodiment of the disclosure. 
         FIG. 5  is a schematic diagram of a computer system according to an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     When a client requests a service from an application server, the client may request a shareable service, meaning that multiple partners are associated with the service. Shareable services may be used to, for example, manage business data and perform business transactions. First, it is important that the client be trusted before processing the client&#39;s request. Second, because shareable services are shared among multiple partners, it is important for a gateway to distinguish among the partners and to be able to maintain data privacy. As an example, the client may request a service associated with a first partner. In that case, the application server may query data for the first partner and not query data for a second partner, which might compete with the first partner, so that the application server does not divulge to the second partner data that is confidential to the first partner. The application server&#39;s access to, but distinction among, multiple partners may be referred to as multi-tenancy. 
     Disclosed herein are techniques for addressing the above issues. Specifically, first, the disclosure may provide for authenticating and authorizing a client, and therefore trusting the client, before processing the client&#39;s request. The request may comprise a client certificate, which may contain encoded in it at least three attributes. The attributes may include a certificate identifier (ID) attribute, a tenant ID attribute, and a role ID attribute. Second, the tenant ID attribute may identify a specific partner and therefore prevent data confidential to that partner from being divulged to other partners. The role ID may implement role-based access control, which may refer to identifying what role the client application may fulfill while using a shareable service and prohibiting the client application from attempting to fulfill any other roles. 
       FIG. 1  is a schematic diagram of a client-server network  100  according to an embodiment of the disclosure. The network  100  may comprise clients  110   1-m  and partner servers  170   1-n  communicatively coupled to a gateway server  140  via a network  120  and through a firewall  130 . The gateway server  140  may be communicatively coupled to an application server  150 , which may, in turn, be communicatively coupled to a back end  160 . The components of the network  100  may be arranged and coupled as shown or in another suitable manner. 
     The clients  110   1-m  may be a notebook computer, tablet computer, desktop computer, mobile telephone, or other device suitable for sending communication to, and receiving communication from, the network  120 . M may be any positive integer. The clients  110   1-m  may be associated with users (not shown), who may operate the clients  110   1-m  using a graphical user interface (GUI). In addition, the clients  110   1-m  may comprise a client application (not shown), which may be any software application coded in any format for purposes of carrying out designated tasks based on automation or user input. The users may use the client application using the GUI. The client application may be used to access a shareable service on the application server  150 . 
     The network  120  may be any network suitable for allowing communication among the clients  110   1-m , the gateway server  140 , and the partner servers  170   1-n . For example, the network  120  may be the Internet or a mobile telephone network. The network  120  may allow communication along wired or wireless channels. 
     The firewall  130  may be a software-based or hardware-based system suitable for controlling communication to and from the server gateway  140 . The firewall  130  may control communication by applying rules to communications. The rules may be set by an administrator (not shown) via the gateway server  140 , the application server  150 , or another suitable device. The firewall  130  may include the gateway server  140 . 
     The gateway server  140  may be a hardware server or other device suitable for serving as an interface between the clients  110   1-m  and the partner servers  170   1-n  on the one hand and the application server  150  on the other hand. The gateway server  140  may translate and convert network protocols in order to allow such communication. By routing all communication to the application server  150  through the gateway server  140 , the gateway server  140  may make authentication and authorization of the clients  110   1-m  simpler. In order to authenticate and authorize the clients  110   1-m , the gateway server  140  may require bi-directional Hypertext Transfer Protocol Secure (HTTPS) or other protocol authentication using mutual certificate-based Secure Sockets Layer (SSL) or Transport Layer Security (TLS), or another suitable form of authentication. HTTPS, SSL, and TLS are incorporated by reference. 
     The application server  150  may be a hardware server or other device suitable for storing data and providing that data to requesting clients. The application server  150  may be dedicated to providing data associated with a single service or with multiple services. When another device, for instance one of the clients  110   1-m , requests a service from the application server  150 , the application server  150  may retrieve from the back end  160  a resource associated with the service. 
     The back end  160  may be a device or devices suitable for storing the resources associated with the service. The back end  160  may reside within or without the application server  150 . The back end  160  may not run independently, but may instead require commands from the application server  150 . For example, the back end  160  may be a database operated using Structured Query Language (SQL), which is incorporated by reference, or any other suitable language or protocol. 
     The firewall  130 , the gateway server  140 , the application server  150 , and the back end  160 , or any combination of those components may be located in the network  120  or a portion of the network  120 . Specifically, those components may be located in a cloud and operate, from the perspective of an entity associated with the application server  150 , in a cloud computing environment. In other words, those components may not be physically located where the entity associated with the application server  150  resides. The cloud may, for instance, be an Amazon® cloud. 
     The partner servers  170   1-n  may be hardware servers or other devices suitable for sending communication to, and receiving communication from, the network  120 . N may be any positive integer. The partner servers  170   1-n  may be associated with partners (not shown), which may be brick-and-mortar merchants such as Safeway® or Albertsons®; gift, credit, and other card issuers such as Starbucks® or Visa®; or other entities unrelated to card processing transactions. Each partner may have a specific ID associated with it. Furthermore, each partner may have multiple partner servers  170   1-n  associated with it. The service described above may be a shareable service, meaning that multiple partners are associated with the service. In addition, the service may use a framework using applications that conform to representational state transfer (REST), which is incorporated by reference. Such applications may be referred to as RESTful applications. 
       FIG. 2 a    is a first portion of a message sequence diagram  200  of the network  100  described in  FIG. 1  according to an embodiment of the disclosure. At step  205 , a user (not shown) associated with the client  110   1  may access a client application (not shown) using a GUI (not shown) on the client  110   1 . Specifically, the user may request from the client application a service associated with the partner  170   1 . The application server  150  may, however, provide the service on behalf of the partner  170   1 . Accordingly, the client  110   1  may begin a process of communication with the application server  150 . The communication may start, however, with mutual authentication between the client  110   1  and the gateway server  140  and with the gateway server  140  authorizing the client  110   1 . 
     Generally, steps  210 - 240  may comprise steps for mutual authentication between the client  110   1  and the gateway server  140 . The steps may comprise messages sent between the client  110   1  and the gateway server  140 , as well as among other components, such as the network  120  and the firewall  130 , between the client  110   1  and the gateway server  140 . The messages may comply with SSL, TLS, or another suitable authentication protocol and be sent and received using HTTPS or another suitable communications protocol. Though steps  220 - 270  are shown, it may be understood that different steps may be used for SSL, TLS, or another suitable authentication protocol. 
     At step  210 , the client  110   1  may send a request for establishment of communication with the application server  150 . For example, the client application may be an Internet browser, so the request may be the client application attempting to access a website. As another example, the client application may be a stand-alone application that directly accesses the Internet without use of a web browser. Because all communication with the application server  150  may be routed through the gateway server  140 , the gateway server  140  may handle the request. At step  215 , in response to the request at step  210 , the gateway server  140  may retrieve a server certificate either locally or from a database. 
     At step  220 , the gateway server  140  may send to the client  110   1  the server certificate. At step  225 , the client  110   1  may authenticate the gateway server  140  based on the server certificate. At step  230 , the client  110   1  may retrieve a client certificate. The client  110   1  may have previously received the client certificate from the partner server  170   1  upon downloading the client application or at some other point. The client  110   1  may store the client certificate either locally on the client  110   1  or in a database accessible to the client  110   1 . The client certificate may be signed by a private certificate authority associated with the application server  150 . The client certificate may have embedded within it three attributes, a certificate ID, a tenant ID, and a role ID, which are described more fully below. 
     At step  235 , the client  110   1  may attempt to send to the application server  150  a request for a shareable service. Once again, the gateway server  140  may handle the request. The request may include the client certificate and may be related to a partner associated with the partner server  170   1 . Alternatively, the client  110   1  may route the request through the partner server  170   1 , which may contain the client certificate. 
     At step  240 , the gateway server  140  may authenticate and authorize the client  110   1 . The gateway server  140  may authenticate the client  110   1  because it received the client certificate from the client  110   1 . The client certificate may not be forged because it is signed by the private certificate authority associated with the application server  150 . The gateway server  140  may therefore authorize the client  110   1  to have access to the shareable service. 
       FIG. 2 b    is a second portion of a message sequence diagram  200  of the network  100  described in  FIG. 1  according to an embodiment of the disclosure. At step  245 , after authenticating and authorizing the client  110   1 , the gateway server  140  may extract the attributes from the client certificate. At step  250 , the gateway server  140  may reformat the attributes into HTTPS headers or an HTTPS body in an Extensible Markup Language (XML), JavaScript Object Notation (JSON) or other suitable message. The message may be in human readable format. At step  255 , the gateway server  140  may send to the application server  150  a request for the shareable service. The request may include the message comprising the attributes. 
     At step  260 , the application server  150  may audit the certificate ID, the tenant ID, and the role ID from the request for legal, billing, or other purposes. For example, if the request is related to a financial shareable service, the application server  150  may be required by law to audit the request. In addition, the application server  150  may audit the request in order to bill the client  110   1  for use of the shareable service. The audit data may indicate which one of the client  100   1-m , for instance the client  100   1 , made which requests. The application server  150  may store audit data either locally or on the back end  160 . 
     At step  265 , the application server  150  may request data from the back end  160 , which may be a resource associated with the shareable service. At step  270 , the back end  160  may send to the application server  150  the resource associated with the shareable service. At step  275 , the application server  150  may forward to the gateway server  140  the resource associated with the shareable service or a response to the request. At step  280 , the gateway server  140  may send to the client  110   1  the resource associated with the shareable service or a response to the request. At step  285 , the client  110   1  or the client application may use the resource or process the response. 
     As another example, the shareable service may be related to gift cards. A merchant may be associated with a partner server  170   1 , and a user associated with the client  110   1  may desire to obtain a Starbucks® gift card from the partner server  170   1 . The client  110   1  may be a notebook computer at a user&#39;s home. The user may access on the client  110   1  a client application, which may be a web browser such as Safari®. In particular, the user may navigate to the merchant&#39;s website to obtain a Starbucks® gift card. The application server  150  may provide the shareable service. Accordingly, the partner server  170   1  may contact the application server  150  through the gateway server  140 , and the partner server  170   1  and the gateway server  140  may authenticate each other. After authentication, the client application may send a request to the shareable service. In other words, the client application may request a gift card or a resource related to the gift card. The application server  150  may respond with a new gift card ID, time stamps associated with the transaction, or other resources associated with the shareable service. While this example relates to gift cards, it is understood that the shareable service may be any shareable or non-shareable service provided in a client-server network such as the network  100 . 
       FIG. 3  is a schematic diagram of the client certificate  300  described in  FIGS. 2 a  and 2 b   . The certificate  300  may comprise a certificate ID, or certificateld, attribute  310 ; a tenant ID, or tenantld, attribute  320 ; and a role ID, or roleld, attribute  330 . In a message from the client  110   1  to the gateway server  140 , the certificateld attribute  310  may be referenced as a common name (CN) attribute, the tenantld attribute  320  may be referenced as an organization (O) attribute, and the roleld attribute  330  may be referenced as an organizational unit (OU) attribute in the subject line of the client certificate  300 , though other associations may be made as well. In a message from the gateway server  140  to the application server  150 , the attributes may maintain their nomenclature. In addition to the certificateld attribute  310 , the tenantld attribute  320 , and the roleld attribute  330 , the client certificate  300  may comprise additional attributes that may identify other aspects of the relationship among the client  110   1 , the gateway server  140 , the application server  150 , and the partner server  170   1 . A private certificate authority (not shown) associated with the gateway server  140  may issue the client certificate  300 . Each partner associated with the partner servers  170   1-n  may have a client certificate associated with it. 
     Each of the attributes may not be forged because the client certificate  300  may be signed by the private certificate authority associated with the gateway server  140 . Because the attributes may not be forged, the attributes may not need to be validated, but may instead be trusted and cannot be repudiated later by the client  110   1  or other legal party. Any additional attributes similarly may be trusted and cannot be repudiated later by the client  110   1  or other legal party. When the gateway server  140  extracts the attributes and forwards them to the application server  150 , the application server  150  may trust the attributes because they came from the gateway server  140 . Each attribute may be a cryptographically random globally unique identifier (GUID), meaning that the same values may not be created twice. Because the attributes may be encoded in the client certificate  300 , they may not be changed without the client certificate  300  signature being invalidated. 
     The certificateId attribute  310  may be an ID that is unique to the client certificate  300 . In other words, every client certificate may have a different value for the certificateId attribute  310 . The certificateId attribute  310  may tell the gateway server  140  and the application server  150  which one of the clients  110   1-m , for instance the client  110   1 , is requesting the shareable service. Before processing the tenantId attribute  320  and the roleld attribute  330 , the gateway server  140  and the application server  150  may confirm that the certificateld attribute  310  value is valid and has not been revoked. A certificateId attribute  310  value may be revoked if, for instance, the client certificate  300  has been stolen or suspected of being stolen. 
     The tenantId attribute  320  may be an ID that specifies which partner owns the data that the client application is attempting to access. Each partner may have a tenant ID associated with it. The tenantId attribute  320  may specify which partner data the client  110   1  may access. Accordingly, the tenantId attribute  320  may ensure segregation of data associated with the partners. In other words, if the client certificate  300  comprises the tenantId attribute  320  and the tenantId attribute  320  indicates a first partner, then the first partner may not access the data of a second partner and no data associated with the second partner may be affected based on the client certificate  300 . 
     The roleId attribute  330  may be an ID that helps to implement role-based access control, which may refer to identifying what role the client application may fulfill while using the shareable service and prohibiting the client application from attempting to fulfill any other roles. For example, the role may be an administrator role, a general role, or another role. The types of roles may be unlimited and may dictate what data transactions the client  110   1  may perform. If the roleId attribute  330  has a value indicating a general role, then the client  110   1  may have limited access to data. If, however, the roleId attribute  330  has a value indicating an administrator role, then the client  110   1  may have nearly unlimited access to data. There may be multiple roleId attribute  330  values associated with a single tenantId attribute  320  value in separate client certificates. 
       FIG. 4  is a flowchart illustrating a method  400  of processing a client certificate according to an embodiment of the disclosure. The method  400  may be implemented in the gateway server  140 . At step  410 , a client certificate may be received. The client certificate may be the client certificate  300 . At step  420 , the client certificate may be authenticated. The client certificate may be authenticated based on a signature in the client certificate. At step  430 , access to a shareable service may be authorized. The authorization may occur in response to the authentication. The access may be authorized to one of the clients  110   1-m . At step  440 , attributes from the client certificate may be extracted. The extraction may be in response to the authentication. The attributes may be the certificateId attribute  310 , the tenantId attribute  320 , and the roleId attribute  330 . At step  450 , a message comprising reformatted attributes may be created. The creation may be in response to the extraction. The reformatted attributes may be based on the attributes and may be trusted based on the authentication. 
       FIG. 5  is a schematic diagram of a computer system  500  according to an embodiment of the disclosure. The system  500  may be suitable for implementing the disclosed embodiments, including the clients  110   1-m , the gateway server  140 , the application server  150 , and the partner servers  170   1-n . The system  500  may comprise a processor  510  that is in communication with memory devices, including a secondary storage  520 , a read only memory (ROM)  530 , a random access memory (RAM)  540 , input/output (I/O) devices  550 , and a transmitter/receiver  560 . Although illustrated as a single processor, the processor  510  is not so limited and may comprise multiple processors. The processor  510  may be implemented as one or more central processor unit (CPU) chips, cores (e.g., a multi-core processor), field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), and/or digital signal processors (DSPs), and/or the processor  510  may be part of one or more ASICs. The processor  510  may be implemented using hardware or a combination of hardware and software. 
     The secondary storage  520  may comprise one or more disk drives or tape drives and may be used for non-volatile storage of data and as an overflow data storage device if the RAM  540  is not large enough to hold all working data. The secondary storage  520  may be used to store programs that are loaded into the RAM  540  when such programs are selected for execution. The ROM  530  may be used to store instructions and data that are read during program execution. The ROM  530  may be a non-volatile memory device that may have a small memory capacity relative to the larger memory capacity of the secondary storage  520 . The RAM  540  may be used to store volatile data and perhaps to store instructions. Access to both the ROM  530  and the RAM  540  may be faster than to the secondary storage  520 . 
     The transmitter/receiver  560  may serve as an output and/or input device of the system  500 . For example, if the transmitter/receiver  560  is acting as a transmitter, it may transmit data out of the system  500 . If the transmitter/receiver  560  is acting as a receiver, it may receive data into the system  500 . The transmitter/receiver  560  may take the form of modems; modem banks; Ethernet cards; universal serial bus (USB) interface cards; serial interfaces; token ring cards; fiber distributed data interface (FDDI) cards; wireless local area network (WLAN) cards; radio transceiver cards such as code division multiple access (CDMA), global system for mobile communications (GSM), long-term evolution (LTE), worldwide interoperability for microwave access (WiMAX), and/or other air interface protocol radio transceiver cards; and other well-known network devices. The transmitter/receiver  560  may enable the processor  510  to communicate with the Internet or one or more intranets. The I/O devices  550  may comprise a video monitor, a liquid crystal display (LCD), a touch screen display, or another type of video display for displaying video and may also include a video recording device for capturing video. The I/O devices  550  may also include one or more keyboards, mice, track balls, or other well-known input devices. 
     The ordering of steps in the various processes, data flows, and flowcharts presented are for illustration purposes and do not necessarily reflect the order that various steps must be performed. The steps may be rearranged in different orders in different embodiments to reflect the needs, desires and preferences of the entity implementing the systems. Furthermore, many steps may be performed simultaneously with other steps in some embodiments. 
     Also, techniques, systems, subsystems and methods described and illustrated in the various embodiments as discrete or separate may be combined or integrated with other systems, modules, techniques, or methods without departing from the scope of the present disclosure. Other items shown or discussed as directly coupled or communicating with each other may be coupled through some interface or device, such that the items may no longer be considered directly coupled to each other but may still be indirectly coupled and in communication, whether electrically, mechanically, or otherwise with one another. Other examples of changes, substitutions, and alterations are ascertainable by one skilled in the art and could be made without departing from the spirit and scope disclosed. There has been described herein an systems and methods for providing a security code of an electronic stored-value card such that users may purchase, redeem, and/or exchange value associated with the electronic stored-value card (e.g., electronic value tokens residing in an electronic wallet). It will be apparent to those skilled in the art that modifications may be made without departing from the spirit and scope of the disclosure. The embodiments described are representative only, and are not intended to be limiting. Many variations, combinations, and modifications of the applications disclosed herein are possible and are within the scope of the disclosure. Accordingly, the scope of protection is not limited by the description set out above, but is defined by the claims which follow, that scope including all equivalents of the subject matter of the claims.