WO2008087332A2

WO2008087332A2 - Method enabling a security policy to be applied to a downloadable application accessing resources of the network

Info

Publication number: WO2008087332A2
Application number: PCT/FR2007/052581
Authority: WO
Inventors: Pierre Cregut; Yragaël LEVEQUE; Cuihtlauac Alvarado
Original assignee: France Telecom
Priority date: 2006-12-29
Filing date: 2007-12-20
Publication date: 2008-07-24
Also published as: FR2911022A1; WO2008087332A3; WO2008087332B1

Abstract

The invention relates to a method for transmitting an application towards a terminal, in a telecommunications network, said application being able to access at least one resource accessible on the telecommunications network. The method is characterised in that it comprises the following steps: a certificate indicating the conformance of the code of the application with secure means for accessing the at least one resource used by the application is generated on the basis of an identification information message from the terminal and a certification key; and the application, the secure means for accessing the at least one resource and the certificate thus generated are transmitted to the terminal.

Description

Method for imposing a security policy on a downloadable application accessing network resources

The present invention relates to controlling access to resources of a resource provider accessible in a telecommunications network, the access being made by downloadable applications on a terminal of the network, in particular a mobile telephone terminal.

More particularly, the invention applies when securing access to resources made available by a resource provider when this access may entail risks for the data of the user of the terminal, resources being able, indeed , manipulate the private data of the user.

We call resource, any value-added service, functionality, hardware or software resource.

In known manner, the application execution platforms, including downloaded applications, on open terminals, for example, on a mobile terminal, access resources of the resource provider by a control performed by the terminal execution platform. In this way, the terminals allow applications to access remote resources that are sensitive in terms of security, while ensuring the security of the user.

Access to remote resources from an application loaded on a mobile terminal and executing, for example, on a Java platform, is achieved for example by sending a short message, also called " SMS "(" Short Message Service "in English terminology), or by sending a multimedia message" MMS "(" Multimedia Messaging Service "in English terminology). Resource providers increasingly want to offer new resources. However, access to these resources must be controlled. Indeed, the user of these resources must be authenticated, this authentication can be performed by the authentication of the user's terminal.

To do this, it must be verified that the application on the user's terminal that accesses these resources is not malicious and does not use user-specific information without the knowledge of the user. this and wrongly.

According to an existing method, the resource provider limits access to these resources to only digitally signed applications, including applications that are signed by this resource provider. This method is particularly used by the MHP type platforms ("Multimedia Home Platform" in English terminology) installed on the decoders or routers ("Set top box" in English terminology). Indeed, the MHP type platforms only allow access to telecommunications network resources to signed applications.

However, this method has the disadvantage that the resources of the provider are accessible only by signed applications.

The disadvantage for the resource provider is that the resource provider must implement an application signature management process (signing and verification acts). The resource provider must therefore systematically intervene in the distribution chain.

The resource provider must, in addition, validate the application, that is to say, ensure, by a review of the application code, that it satisfies the obligations of the security policy that he defined. In the context of the present invention, it is called "security policy" to impose a predetermined sequence at certain predetermined stages of the execution of an application used for the exploitation of said resources.

A security policy may also be, for example, the prohibition of any access to personal data of the user. In addition, according to this method, access to features is limited to a controlled group of developers and application users. In addition, the validation procedure is very often complex.

Indeed, this procedure requires that a specialist analyzes the code to ensure the good behavior of the application. In the example security policy presented above, you must read the code to verify that no request can be sent to a personal database.

The invention aims to remedy at least one of the drawbacks of the prior art by proposing a method of transmitting, in a telecommunications network, an application to a terminal, said application being able to access at least one accessible resource on the telecommunications network, characterized in that it comprises the following steps:

generating a certificate indicating the compliance of the code of the application with secure means of access to said at least one resource used by said application, from a terminal identification information and a key of certification; and

- transmission to the terminal of the application and the certificate thus generated.

The present invention makes it possible to control access to accessible resources in a telecommunications network, the access being achieved by an application transmitted to a terminal of the telecommunications network, in particular a mobile telephone terminal.

For this, the present invention provides that (for example, the reception from the terminal of a request comprising a terminal identification information) is generated from the terminal identification information of the terminal. user, and the certification key, a certificate indicating the compliance of the application with the secure means of access to resources.

Said secure means of access to said at least one resource are therefore supposed to comply with a security policy relating to access to said resource. The certificate thus generated and customized to the terminal ensures that the application loaded uses the resources on the telecommunications network according to a security policy defined, for example, by the provider of this resource and not the phone manufacturer or the developer of the application, the latter may have malicious intent.

Advantageously, the burden of verifying compliance of the application code with the security policy of a resource provider does not rely on said resource provider.

The method therefore preferably comprises, before said generation step, a preliminary step of verifying the compliance of the code of the application with the secure means of access to said at least one resource used by said application.

According to one embodiment, these secure means of access to said at least one resource are transmitted to the terminal in addition to the application and the certificate. This embodiment is obviously useful in the case where the terminal does not yet contain these secure means of access. In this case, it will be possible, optionally, to insert said certificate into these secure means of access.

The present invention also aims to provide a method for accessing at least one accessible resource on the telecommunications network from an application installed on a terminal, characterized in that it comprises the following steps:

receiving a request for access to said at least one resource, said request comprising a certificate indicating the compliance of the application code with secure means of access to said at least one resource used by said application and identifying the terminal; and

- verification of said certificate.

According to this method, the certificate is not verified by the terminal but by the service platform allowing access to resources made available when calling a resource.

The present invention also aims to provide a method of loading an application on a terminal, said application being able to access at least one accessible resource on a telecommunications network, characterized in that it comprises the following steps: sending a request for loading said application, the request comprising identification information of the terminal; and

receiving said application and a certificate indicating the compliance of the application code with the secure means of access to said at least one resource used by said application and identifying the terminal.

As described above, the present invention makes it possible to control access to resources of a resource provider in a telecommunications network, the access being provided by an application loaded, in particular, on a mobile telephone terminal.

For this, the present invention is based on a step of issuing a request comprising the identifier of the terminal and on a step of receiving an application and a certificate indicating the compliance of the application code with secure means of access to resources.

In this way, the certificate makes it possible to guarantee that the application loaded uses the resources of the provider on the telecommunications network according to a security policy defined, for example, by the resource provider and not by the telephone manufacturer or the developer of the network. the application, the latter may have malicious intent.

According to one embodiment, the terminal receives these secure means of access to said at least one resource in addition to the application and the certificate. As indicated above, this embodiment is useful in the case where the terminal does not yet contain these secure means of access. In this case, it will be possible, optionally, to insert said certificate in these secure means of access.

The present invention also aims to provide a method for executing, on a terminal, an application able to access at least one accessible resource on the telecommunications network, characterized in that the method comprises a transmission step a request to access said at least one resource by secure means of access to said at least one resource, said request comprising a certificate, said certificate indicating the compliance of the application code with the secure means access to said at least one resource used by said application and identifying the terminal.

According to this method, when accessing a provider resource, the certificate is issued when sending the request, by the secure means of access to resources.

Correlatively, the invention also provides a device for transmitting, in a telecommunications network, an application to a terminal, said application being able to access at least one accessible resource on the telecommunications network, characterized in that includes the following means:

means for generating a certificate indicating the conformity of the code of the application with secure means of access to said at least one resource used by said application, based on terminal identification information and a certification key; and

means for transmitting, to the terminal, the application and the certificate thus generated.

This device has the same advantages as the transmission method, in a telecommunications network, of an application to a terminal, said application being able to access at least one accessible resource on the telecommunications network briefly described above.

According to one embodiment, said transmission means are able to transmit to the terminal said secure means of access in addition to the application and the certificate.

The present invention also aims to provide a device for accessing at least one resource accessible on the telecommunications network from an application installed on a terminal, characterized in that it comprises the following means:

means for receiving an access request to said at least one resource, said request comprising a certificate indicating the compliance of the application code with secure means of access to said at least one resource used by said application and identifying the terminal; and

means for verifying said certificate. This device has the same advantages as the method of accessing at least one resource accessible on the telecommunications network from an application installed on a terminal briefly described above.

The present invention also aims to provide a device for loading an application on a terminal, said application being able to access at least one accessible resource on a telecommunications network, characterized in that it comprises the following means:

means for transmitting a request for loading said application, the request comprising terminal identification information; and

means for receiving said application, secure means of access to said at least one resource used by said application and a certificate indicating the compliance of the application code with the secure means of access to said at least one resource a resource used by said application and identifying the terminal.

This device has the same advantages as the method of loading an application on a terminal, said application being able to access at least one accessible resource on a telecommunications network briefly described above.

The present invention also aims to provide a device for executing, on a terminal, an application able to access at least one accessible resource on the telecommunications network, characterized in that the device comprises transmission means a request to access said at least one resource by secure means of access to said at least one resource, said request comprising a certificate, said certificate indicating the compliance of the application code with the secure means of access said at least one resource used by said application and identifying the terminal.

This device has the same advantages as the method of executing, on a terminal, an application able to access at least one accessible resource on the telecommunications network briefly described above.

According to yet another aspect, the invention relates to a computer program loadable into a computer system, said program containing instructions enabling the implementation of the method of transmission in a telecommunications network of an application as explained hereinabove. above when this program is loaded and executed by the computer system.

According to yet another aspect, the invention relates to a computer program loadable in a computer system, said program containing instructions for implementing the method of access to at least one resource accessible on the telecommunications network from an application as explained above when this program is loaded and executed by the computer system.

According to yet another aspect, the invention relates to a computer program loadable in a computer system, said program containing instructions for implementing the method of loading an application as explained above when this program is loaded and executed by the computer system.

According to yet another aspect, the invention relates to a computer program loadable in a computer system, said program containing instructions for implementing the method of executing an application able to access at least one resource accessible on the telecommunications network as explained above when this program is loaded and executed by the computer system.

According to another aspect, the invention also provides a computer program product that can be loaded into a programmable device, characterized in that it comprises an application able to access at least one accessible resource on the telecommunications network, means secure access to said at least one resource and a certificate indicating the compliance of the application code with the secure means of access to the said at least one resource used by said application, and generated from a terminal identification information and a certification key.

The present invention also aims to provide a certificate comprising information indicating the compliance of the code of an application with secure means of access to at least one resource used by said application, and identifying a terminal for hosting the application. .

Other aspects and advantages of the present invention will appear more clearly on reading the description which follows, this description being given solely by way of nonlimiting example and with reference to the appended drawings, in which:

- Figure 1 shows a hardware architecture of a telecommunications network on which the invention is implemented; and

- Figure 2 illustrates a method and a device for transmitting and executing an application according to the invention.

It is illustrated by means of FIG. 1 and FIG. 2 a method and a device for transmission in a telecommunications network of an application, the application being able to access at least one accessible resource on the telecommunications network. , a method and a device for accessing at least one resource accessible on the telecommunications network from an application installed on a terminal, a method and a device for loading an application on a terminal, and a method and an application execution device adapted to access at least one resource accessible on the telecommunications network, the application securely accessing resources of a resource provider over a telecommunications network. This security is achieved by marking the applications downloaded to a user's terminal by means of a certificate linked to a code compliance property of downloaded applications with the secure means of access to resources, these secure means of access. implementing a security policy. According to the invention, the applications calling said secure means of access to resources of the resource provider, allow the user to access these resources only via these same secure means of access.

Figure 1 illustrates the hardware architecture on which the invention is implemented.

This architecture consists of an application developer 1 who, in particular, develops applications, a resource provider capable of providing a platform of services 2 allowing access to the resources made available, of an operator certification system capable of providing a platform 3 providing, on the one hand, means of secure access to resources of a resource provider while respecting a security policy and, on the other hand, means of certification an application accessing these resources for a given user. The platform of the certification operator can furthermore manage the transmission of applications to user terminals in accordance with the invention, this platform is also called a portal. The architecture further includes a terminal 4 of a user on which the applications are loaded and executed.

The resources of the resource provider are, in particular, value-added services that can be used by applications that can be downloaded to the mobile terminals of the users.

The certification operator has a pair of cryptographic keys, namely a private key and a public key, in particular to sign certificates. This key pair is uniquely attached to this operator.

Using this certificate and cryptographic keys, the resource provider is able to verify the origin of the certificate.

According to a particular embodiment, the resource provider and the certification operator form a single entity.

The terminal 4 of a user is in particular a mobile terminal on which runs an execution platform, for example, a Java platform. The terminal is connected via the network of telecommunications to at least one platform of a certification operator and at least one platform of a resource provider. The terminal, by means of its execution platform, is able to download applications that are accessible from a portal.

The terminal is uniquely identified by means of an identifier, this identifier also being that of the user of the terminal. This is, for example, the phone number of the mobile terminal. This identifier also makes it possible to control access to resources of the resource provider.

The platforms 2 and 3 further include means for authenticating the terminal, in particular by means of the identifier of the terminal, in order to detect unauthorized uses of the identifier.

The terminal comprises storage means capable of storing a plurality of applications. The execution platform present on the terminal allows the execution of these applications. However, as managed by the runtime platform, each application has its own application context, including a program and data space for running the application. . By means of such a platform, an application can not access the context of another application loaded on the terminal.

For example, a MIDP (Mobile Information Device Profile) Java operating platform running on a mobile telephone terminal has the property of isolating the contexts between the different applications written in MIDP Java language, called midlets, which are present in the terminal.

In particular, an application can not manipulate the code of another application present in the mobile terminal, nor download a new application.

As for the application developer 1, it develops and makes applications available to users via a portal, these applications calling in particular resources of the resource provider.

These applications have a structure compatible with a basic level of modularity. Indeed, it is possible to realize these applications to from a plurality of libraries. Each library includes a set of functionalities accessible through an interface describing a set of entry points, also called methods, and allowing access to these features.

In addition, a method in one library can use a method from another library.

For example, in the Java language, a Java archive (with the extension ".jar" and grouping Java libraries) is composed of a set of Java files in compiled code corresponding to libraries, each library can be handled separately in the archive.

In addition, it is possible to protect data against access by codes external to the library. This access is defined in particular by the declaration of this data. Indeed, according to the Java language, a data declared "private" is not accessible from outside the library.

Similarly, entry points to the library are limited, for example, by means of statements in the library interface.

For example, according to the Java language, the visibility of the fields and the methods of the libraries is defined by means of their declaration. Indeed, if a method or data is declared private then it will not be visible from outside the library by other objects.

Referring to Figure 2, the method of loading, transmitting and executing an application is now described.

In order to realize an application, an application developer is provided with a development library (step E21). This development library is the resource access interface of the resource provider. The application developer is able, on the one hand, to develop applications for accessing resources of the resource provider using this interface, and, on the other hand, to simulate access to these resources.

The development library which aims to control access to resources and define the appropriate security policy is developed, for example, under the control of the certification operator or the resource provider.

The application developer develops (step E22) a new application calling the secure means of access to resources of a resource provider using the development library.

After developing this application, the application developer makes it available to customers (step E23). For this, the application is stored on a portal, for example, on the portal of the certification operator. A portal is a website offering a gateway to resources.

The client who wishes to use this new application sends a loading request, via his terminal, to the portal 3 in order to obtain the application (step E24).

The request includes the identifier of the terminal, for example, the phone number of the latter.

This request is sent, for example, by means of an SMS type message and is authenticated by the portal.

Upon receipt of a request, the portal substitutes for said development library a deployment library comprising secure means of access to resources of the resource provider. The deployment library also includes a certificate indicating the compliance of the application code with the secure means of access to resources of the resource provider used by said application, the certificate being generated from the identification information of the application. terminal and the private key of the certification operator (step E25). In this way, this certificate certifies that the application that will be transmitted to the terminal complies, via the secure means of access to resources, the resource access policy of the resource provider, this certificate is also linked to the terminal.

The deployment library is customized on the fly, that is to say dynamically, in particular, depending on the certificate generated and therefore the terminal identification information. Prior to the generation of the certificate, it is verified that the code of the application complies with the secure means of access to resources of the resource provider, that is to say it is verified that access to resources by the application are made according to the access library and therefore comply with the resource access security policy.

The portal then transmits the complete application to the terminal, the application comprising the application code developed by the application developer and the previously customized deployment library (step E26).

The transmission is carried out on the return channel, for example by using an MMS message containing the application or an SMS message containing a usable link, for example, only once to access the application.

Alternatively, it can be provided that the transmission to the terminal of all the required software bricks is performed in a fractional manner. In this case, the certificate of the invention will be attached to a "main" fragment, which describes the entire application, but may not contain the deployment library. However, after being installed on the terminal, this main fragment must be able to be unambiguously associated with the libraries (of which, of course, the deployment library) for which the compliance of the application code has been verified. For this purpose, it will be possible, for this purpose, to integrate in the main fragment checksums calculated by means of cryptographic hash functions applied to the codes of these libraries. The advantage of this variant is that it allows to share a number of libraries between several applications, in which case a terminal will obviously not need to load these libraries more than once (some libraries can even be pre-loaded on the terminals before their marketing).

After loading the application on the user's terminal, the user is ready to execute. The user starts the execution of the application (step E27) using the resources accessible from the service provider platform of the resource provider, these resources being accessible through the interface provided by the access library to resources.

This library ensures compliance by the application of the security policy for access to resources of the resource provider by requesting, for example, confirmations to the user (step E28).

When accessing a resource of the resource provider, the library sends, to the service platform 2, a request including the certificate generated during the transmission of the application.

The requests are transmitted securely and confidentially, in particular by using a secure exchange protocol, for example the SSL ("Secure Socket Layer") protocol.

This transmission is performed, for example, by sending an SMS.

The service platform 2, by means of the certificate, ensures that the request for access to a resource is performed by an authorized user and according to the appropriate security policy and certified by the certification operator (step E30) .

Then, after this step, the service platform 2 allows access to the requested resource (step E31).

In accordance with the invention, it should be noted that without decompiling the application or copying the certificate of an authenticated application into another application, an application can not use the resources of a resource provider in any way other than by executing the code of the library.

Indeed, the certificate is necessary to use a resource of a resource provider and can not be copied because the certification operator has a pair of cryptographic keys, namely a private key and a public key, which allow him to sign a certificate and that the supplier is able to verify this certificate. In addition, in the application, only the code in the library can access resources from the resource provider.

In addition, the isolation property of application contexts in the terminal's runtime platform ensures that other applications can not access resource provider resource library code.

Thus, a bona fide user is protected against any malicious use of resources made through the application downloaded from the portal or by another application.

However, if the user is malicious and extracts the certificate generated by the certification operator to insert it into another application, then two cases are to be considered.

If this other application is for its own phone, the security controls protecting the user against unauthorized use of resources are removed.

If, on the other hand, this other application is used by another user on another phone, then the account and resources of the first malicious user are used. Indeed, the certificate inserted in this other application is that obtained by the malicious user who could impersonate the attacked terminal because each terminal is uniquely identified.

As a result, a malicious user can not obtain a usable certificate to incorporate it into an application, except to endanger his own account.

Furthermore, it has been observed that it is not always possible to directly customize the code of the application, including libraries.

Indeed, it is sometimes not possible to customize data related to the application and only accessible by it. For example, for an application written in Java MIDP, the application consists of a descriptor called JAD file ("Java Application Descriptor") in English terminology) and an archive containing the compiled code called JAR file.

The portals are able to customize the JAD file on the fly, but by no means the JAR file. Indeed, the data stored in the JAD file can only be accessed by the application.

In this case, the certification operator can attach to the application data that is calculated based on the terminal identification information that is inaccessible to other applications.

Thus, according to this embodiment, the certificate is not directly inserted in the deployment library but issued with the application and the deployment library.

The communication methods according to the invention consist in memorizing the certificate generated by the operator in the private data of the application.

In this case, only the library must access this data.

Static analysis techniques that control calls to resources allow such verification. Thus, the language used to code the application must be able to control whether the executable code of an application uses, in a library, a resource of the resource provider managed by the resource provider's service platform.

In the case of the MIDP Java language, it is necessary to verify that the certificate attribute, called CERT, contained in the JAD file is not accessed, except by means of the library.

Thus, it is a question of checking that the application does not make any call to the method entitled MIDIet.getAppPropertyfCERT ") having as parameter the attribute CERT.

To do this, it must be verified that there is no call to the MIDIet.getAppProperty method consisting of a static resolution problem also known as "devirtualization" of method calls, or that the arguments of calls to the MIDIet.getAppProperty method does not include the string "CERT". It is then necessary to devirtualize and to solve the possible chains to verify that they are different from the name of the attribute. This type of analysis is carried out according to known methods, such as those described, for example in the document entitled "Accurate Analysis of String Expressions" by Aske Simon Christensen, Anders Moller and Michael I. Schwartzbach published in "Proceeding 10th International Static Analysis" Symposium "(SAS'03), Lecture Notes in Computer Science, Vol. 2694, Springer Verlag, 2003, or in the document entitled "Improving the Security of Downloadable Java Applications with Static Analysis" by Pierre Crégut and Cuihtlauac Alvarado, published in "Workshop on Bytecode Semantics, Analysis and Transformation" (BYTECODE05), Electronic Notes in Computer Science, Vol. 141, Elsevier, 2005.

According to this particular embodiment, the step E23 of FIG. 2 is replaced by a step of submission, by the application developer, of the application developed in order to verify that the application does not access the private data directly. specializing the application, except via resource access libraries of the resource provider.

In addition, still according to this embodiment, step E25 is replaced by a step of generation, by the portal, of the private data of deployment. This data contains a certificate generated from the terminal identification information and the private key of the certification operator. This data is joined to the other private data of the application.

In addition, the step E26 is replaced by a step of transmission to the terminal, by the portal, of the complete application comprising the code of the application generated by the application developer, the access libraries to the resources of the resource provider and the personalization data, that is, the certificate.

This transmission is performed by the return channel, for example by means of an MMS message containing the application or an SMS type message containing a link that can be used once to access the application.

Claims

1. A method of transmitting, in a telecommunications network, an application to a terminal, said application being able to access at least one accessible resource on the telecommunications network, characterized in that it comprises the following steps:

2. Transmission method according to claim 1, characterized in that one transmits further to the terminal said secure means of access.

3. Transmission method according to claim 2, characterized in that the generated certificate is inserted into the secure means of access to said at least one resource.

4. A method for accessing at least one accessible resource on the telecommunications network from an application installed on a terminal, characterized in that it comprises the following steps:

- verification of said certificate.

5. A method of loading an application on a terminal, said application being able to access at least one accessible resource on a telecommunications network, characterized in that it comprises the following steps: sending a request for loading said application, the request comprising identification information of the terminal; and

receiving said application and a certificate indicating compliance of the application code with secure means of access to said at least one resource used by said application and identifying the terminal.

6. Loading method according to claim 5, characterized in that the terminal further receives said secure means of access.

7. Loading method according to claim 6, characterized in that the generated certificate is inserted in the secure means of access to said at least one resource.

8. A method of executing, on a terminal, an application able to access at least one accessible resource on the telecommunications network, characterized in that the method comprises a step of transmitting a request to access said at least one resource by secure means of access to said at least one resource, said request comprising a certificate, said certificate indicating the compliance of the application code with the secure means of access to said at least one resource used by said application and identifying the terminal.

9. Device for transmitting, in a telecommunications network, an application to a terminal, said application being able to access at least one accessible resource on the telecommunications network, characterized in that it comprises the following means:

10. Transmission device according to claim 9, characterized in that said transmission means are adapted to transmit to the terminal said secure means of access in addition to the application and the certificate.

1 1. Device for accessing at least one resource accessible on the telecommunications network from an application installed on a terminal, characterized in that it comprises the following means:

means for verifying said certificate.

12. Device for loading an application on a terminal, said application being able to access at least one accessible resource on a telecommunications network, characterized in that it comprises the following means:

13. Device for executing, on a terminal, an application able to access at least one accessible resource on the telecommunications network, characterized in that the device comprises means for transmitting a request for accessing said at least one resource by secure means of access to said at least one resource, said request comprising a certificate, said certificate indicating the compliance of the application code with secure means of access to said at least one resource used by said application and identifying the terminal.

14. Computer program loadable in a computer system, said program containing instructions for implementing the method of transmission in a telecommunications network of an application according to any one of claims 1 to 3, when this program is loaded and executed by said computer system.

15. A computer program loadable in a computer system, said program containing instructions for implementing the method of access to at least one resource accessible on the telecommunications network from an application according to claim 4, when this program is loaded and executed by said computer system.

16. A computer program loadable in a computer system, said program containing instructions for implementing the method of loading an application according to any one of claims 5 to 7, when the program is loaded and executed by said computer system.

17. A computer program loadable in a computer system, said program containing instructions for implementing the method of executing an application able to access at least one accessible resource on the telecommunications network, according to claim 8 when this program is loaded and executed by said computer system.

18. Computer program product that can be loaded into a programmable device, characterized in that it comprises an application able to access at least one accessible resource on the network of telecommunications, secure access means to said at least one resource and a certificate indicating compliance of the application code with the secure means of access to said at least one resource used by said application, and generated from an identification information of a terminal and a certification key.

19. A certificate comprising information indicating the compliance of the code of an application with secure means of access to at least one resource used by said application, and identifying a terminal intended to host the application.