KR101389264B1 - one time password including integrity code and authentication system based on it - Google Patents

Abstract

The present invention provides a method for generating a one-time password including integrity data and an authentication scheme based on the method. When the service server is transmitted to the wired / wireless communication terminal of the integrity code user generated based on the summary data of the service item requested by the client terminal, the integrity code is input to the one-time password generator and the one- Time-Password, OTP). The user transmits the one-time password to the one-time password authentication server using the wired / wireless communication terminal or the network to which the client terminal is connected, and authenticates the one-time password upon receiving the one-time password authentication server. The service server that has received the authentication result achieves security by providing or denying service to the client terminal according to the result of the authentication.

One time password, OTP, One Time Password (OTP) Generator, Time-Synchronization, One-Time Password, Integrity Code, Memory Hacking, Challenge-Response

Description

A one-time password-based authentication method including an integrity code, and a system thereof,

The present invention relates to a method of generating a one-time password including an integrity code in an environment in which a client and a service server are connected, and an authentication method and an authentication system using the same.

Generally, the one time password scheme can be largely divided into a challenge-response type scheme and a time synchronized type scheme.

A one-time password (OTP) generator is a portable device that can be carried by a user. In the challenge-response method, a challenge of the server can be input to generate a one-time password. In case of the time sync method, Is generated.

In the challenge-response type one-time password (OTP), when a client terminal requests a connection to a server, the server transmits a challenge value composed of several bytes to the client terminal, and the client terminal transmits a challenge The hash result is derived using a hash function that is shared with the server by combining the number and the organization code. Such a hash result is an expression function that is provided in a manner that the user can easily input and provides such a representation function. The value output from the expression function is a response, a one-time password, or an OTP. Therefore, 'response', 'one-time password', and 'OTP' in this document mean the same generated one-time password. This process is summarized as the following equation.

Here, h denotes a hash result, H () denotes a one-way hash function, C denotes a challenge, S denotes a serial number shared with the server, A denotes an authority code, and other reservation codes. Rep () is a representation function, and OTP is a generated one-time password.

A hash function is a function that takes long data without any length restriction as its input value and outputs a value (hash value) of a fixed size of 128 bits to 160 bits. To have such a hash function cryptographically secure, the input value must be unidirectional from the output value, and a small change in the input value must sufficiently generate the chain effect that results in a large change in the output value. It must be numerically impossible to find different input values giving the same output value. Common hash functions are md5, sha, and sha1. The hash function module 411 defines a module in which such a hash function is implemented in software or hardware.

This response value is transmitted to the server through the client terminal requesting the connection by the user and the server authenticates the client terminal when the leasing value is equal to the response value derived by the server. In actual implementation, the hash function provides a long output value of 128 bits to 160 bits. Therefore, the response (OTP) is expressed in decimal numbers from 6 to 10 digits (or a defined length) This function can be implemented by simply reducing the size by using XOR or by using another hash function. This is called an expression function Rep (representation function), and a module implementing this is defined as an expression module 412.

One-time password (OTP) of time synchronization method is different from challenge-response method in that server and one-time password (OTP) generators share synchronized time, thereby generating a one-time password (OTP) to be. The one-time password by the time sync method is derived by the following equation.

Where T is the time shared with the server, S is the one-time password (OTP) generator and the serial number shared with the server, A is the authority code and other reserved code. The time synchronization method can be more convenient than the challenge-response type one-time password in terms of the user since the user is generated at a predetermined time interval without receiving and inputting the challenge from the server. However, since the authentication of the same one-time password is allowed for authentication for a certain period of time, it is known that the challenge-response type one-time password is superior in terms of security.

The challenge-response method is characterized in that authentication is not failed when a correct one-time password is input due to accumulation of time errors, but a process of receiving a response from the server is added. In the time sink method, However, there is a disadvantage in that the security may be weakened because time errors with the server may accumulate and authentication of the same one-time password may be allowed for authentication for a certain period of time.

The attack on the challenge-response one-time password scheme is possible by continuously accumulating the response to the challenge. For example, when an attacker who intends to attack user A continuously accumulates a challenge received and a response received by a specific user to complete a challenge-response table of user A, the server A impersonates A and receives a response, The user can obtain the authentication by finding the corresponding response using the server and transmitting the response to the server. In effect, an attacker does not have to wait 100% for the challenge-response table to attack user A. If this table is partly built and the server sends the same thing that it had previously generated the challenge, the attacker could obtain the response from the partially completed table and use it to gain authentication.

The attack on the time synchronization type disposable cipher system uses the authentication expiration time of the one-time password provided to the time sink method (usually set to one minute) as the main attack path. If the attacker's Trojan-horse attack tool is installed and the user B's terminal is attempting authentication and authentication, the attacker will continue to monitor the user B's terminal, and user B will input the one-time password of the time sink method, ), It modifies the one-time password value to another value and transmits it to the server, and transmits the real one-time password inputted by user B to the monitoring attacker. This attack method is called so-called memory hacking. The attacker transmits this to the server within the validity period of the authentication and receives the authentication and proceeds with the service. These attacks have occurred several times in recent Internet banking and are expected to cause more serious damage in the future.

Therefore, in order to enhance the security of the one-time password-based authentication method, a method and system are required to include the service request data in the one-time password so that the OTP authentication server can check the integrity of the one-time password in the authentication step.

Accordingly, the present invention has been made to solve the hacker's attack using the Trojan-type hacking tool, and it is an object of the present invention to provide a method and system for protecting a hacker's attack by using a wired / wireless communication terminal, Or a wired / wireless communication terminal, thereby allowing the client terminal to bypass the control of the client terminal 100 using a hacking tool in the form of a Trojan horses, By transmitting and authenticating the one-time password including the integrity code 2100 through the network or the network to which the client terminal is connected, an attack based on the memory hacking is completely blocked.

The method includes an OTP generator 500 for generating a one-time password, a bypass network for transmitting a one-time password to the SMS or ARS, an SMS or ARS server 400 for connection to a wired and wireless network, And an OTP authentication server 300 for authenticating the one-time password 1100 including the password 2100.

In addition, the present invention is a new technical concept that combines the challenge-response method and the one-time-use cryptosystem of the time sync method. It does not reflect only the time-synchronized challenge value received at the server and other static serial, Integrity code and The discretized time data By adding the input value fused static data and dynamic data to Lindsay previous intercept of - overcomes the disadvantages of providing a challenge response to the same problems of response manner. What is Time Sync? Since the integrity code is received, there is a fundamental difference in terms of completely blocking the loopholes of the time synchronization method , which has been different from the configuration in which only one authentication opportunity is given,

An integrity code 2100 derived from a service request item and a request time, a one-time password 1100 including an integrity code, an OTP generator 500 for a one-time password, an OTP authentication server 300 for authenticating the password, The service server 200 receiving the service request, the wired / wireless communication terminal 600, and the SMS / ARS server 400 for transmitting the integrity code 2100 to them is a key solution of the present invention.

And generates a one-time password based on the integrity data to secure the safety of the electronic financial transaction by fundamentally blocking the memory hacking attack that modifies the service request items in the client terminal by generating the integrity code including the service item requested by the user.

The client terminal 100 transmits a one-time password including an integrity code to the OTP authentication server through a heterogeneous bypass network instead of the network to which the client terminal 100 is connected, thereby blocking attacks such as memory hacking based on the Trojan-based hacking tool. Applicable fields include, for example, Internet banking, and phone banking using wired and wireless telephone networks.

The user authentication is looped back to the OTP authentication server 300, the server server 200, the client terminal 100, the wireless communication terminal 600, the SMS / ARS server 400 and the OTP authentication server 300, The integrated authentication of all the components participating in the authentication step is performed, thereby enhancing the security degree dramatically.

In the present invention, in generating a one-time password, not only the challenge value and other static serial and authority codes are reflected in the input value but the discretized time data added together with the integrity code is added to the input value, ≪ / RTI > integrity.

This feature of the present invention is that the eavesdropper continuously collects the challenge and the response, and if the same challenge is used to detect the response, it completely blocks the possibility of attack in the existing challenge-response type one-time password system In addition, from the viewpoint of the one-time cryptosystem of the time synchronization method, there is an effect that the authentication attempt of the non-person can be completely blocked during the authentication valid period of the predetermined time.

In conclusion, it strengthens the advantages of challenge-response one-time passwords and time-sync one-time password schemes and essentially blocks the memory hacking possible by manipulating service request data.

The components constituting the present invention include a client terminal 100, a service server 200 for providing contents related to a service according to a service provision request of the client terminal, an integrity code 2100 for generating a one- An OTP authentication server 300 for confirming the received one-time password, an SMS or ARS server 400 for receiving the transmitted integrity code, a wired / wireless communication terminal 600 for transmitting OTP information, and an OTP Generator 500 includes both the challenge-response scheme and the time synchronization scheme described above.

Authentication methods using one-time passwords are used as authentication methods for access control of security systems and financial transactions including Internet banking because of the advantage of achieving high degree of security. The following is an explanation of a service flow related to an authentication system using a conventional one-time password (OTP) by taking an Internet banking service as an example (refer to FIG. 1).

When the client terminal 100 transmits a user ID and a password to the Internet banking server and logs in, it can receive general services such as inquiry. When requesting a service having a high security level such as an account transfer, the Internet banking server requests the OTP authentication server to generate a challenge, and the OTP authentication server generates a challenge and transmits the challenge to the service server The step of generating and transmitting the challenge in the case of the synchronous scheme may be omitted). The Internet banking server transmits the challenge to the client terminal 100. The user enters the challenge in an OPT generator (which may also be implemented in an independent handheld device or in a mobile phone) to derive the challenge. The client terminal 100 receives the response from the user and transmits the response to the Internet banking server. The Internet banking server transmits the response to the OTP authentication server again, and the one-time password (OTP) If one of the responses is the same, it notifies the Internet banking server of the authentication success and provides a service with a high security level requested by the user.

Recent techniques relating to disposable ciphers are disclosed in Korean Patent Laid-Open No. 10-2007-0077569 (Prior Art Document 1) and US Publication No. US2006 / 0136739 (Prior Art Document 2).

The prior art document 1 relates to a system and method for a one-time password service using a mobile phone. When the OTP authentication server generates a challenge, it transmits the challenge to the mobile phone via the SMS server and transmits the response to the mobile phone using a one- (OTP) and transmits the one-time password to the server through the client terminal 100 to authenticate the user. This method allows the user to easily receive the challenge and derive the response.

The prior art document 2 is related to a method and apparatus for generating a one-time password in a portable mobile device, receives a response for generating a one-time password from a global authentication server, generates a one-time password using the response, (See page 2). The core configuration is similar to the prior art document 1. These prior art documents have been further enhanced in terms of the combined use of wireless and wired networks and are a step ahead of the technology of transmitting and receiving existing one-time passwords over a single network connected by a client PC .

Despite such technological advances, the authentication method of the service server using the conventional one-time password (OTP) proposed by the prior art document 1-2 provides a relatively strong security level, but the client terminal 100 has a hacker- It has become known by a recent series of events that this disposable cryptosystem can be disabled if a hacking tool in the form of a Taojan Horse is installed and seized. A hacker who hacked a Trojan-shaped hacking tool to install on a user's PC intercepts the user's typed password (OTP) through kernel hooking or keyboat hooking. Thereafter, the OTP of the client terminal 100 is modulated to a different value before the user inputs it, and the client terminal 100 processes the input of the one-time password as a failure. This is a typical example of memory hacking as described above, and many cases of hacking of Internet banking have been reported recently.

 Then, the hacker transmits the one-time password (OTP) intercepted by the hacker to the service server within the expiration date of the one-time password (usually set to one minute) and receives the one-time password authentication. This trend is not merely a theoretical one, but recent news has shown that this attack has been conducted by Chinese hackers over a number of occasions, and many users have withdrawn funds from their accounts to a third party account that they do not know at all.

In the case of memory hacking using such a Trojan-shaped hacking tool, both the challenge-response method and the time-synchronization method of one-time password (OTP) have the same vulnerability. Even if a challenge is received by using a mobile phone as in the prior art document 1-2, a disposable password must be input to the client terminal 100, and thus the client terminal 100 must be interrupted by a hacker will be. Therefore, in the OTP-related authentication system proposed so far, authentication using the OTP becomes meaningless when a trojan-based hacking tool that takes control of the client terminal 100 is planted.

The general service configuration of the present invention is as shown in FIG. The OTP authentication server 300 receiving the service request items and the request time received from the client terminal 100 by the service server 200 generates the integrity code 2100 and transmits the integrity code 2100 to the SMS / ARS server 400 To the wired / wireless communication terminal. This is input through the input unit 50 of the one-time password generator, which is stored in the memory unit 40. The control unit receives the serial number stored in the memory unit. This serial number is a serial number shared by the OTP authentication server and the one-time password generator in registering / distributing the one-time password generator. The control unit receives the discretized time data from the discretization time unit 20. The discretized time data refers to time data in the form of discretization in minutes or days, for example, on the day of the year (eg, 2008.03.10.18.30) or on the day of the month (eg, 2008.03.10.18).

For example, if the daily discretization can be expressed as 2008.107 (the 107th day of a year), and if it is discretized on a weekly basis, the disaggregated time data may be formed by 2008.15 (the 15th week of the year). The configuration recommended in the present invention is recommended to take discrete data for a number of days in a year or a week in a year. The reason for this recommendation is that the probability that the same integrity code will be thrown through the wired / wireless communication terminal in the server within one day or one week is very small, and the authentication failure gap (Gap ) (Which is different from the effective authentication time of the time synchronization method). Therefore, the present invention has been derived in order to fundamentally solve such a problem.

Further, the control unit reads other reservation codes stored in the memory unit, and the other reservation codes may include institution codes, service codes, and the like.

The control unit generates the hash input data block 1000 by connecting the integrity code, the serial, the discretized time data, and other reservation codes as shown in the following Equations 3 and 4 and inputs it into the hash function and the expression function (OTP) 1100. In this case, The configuration for generating the one-time password in the present invention is as follows.

Here, the service request item is an item requested by the client terminal to the service server, and includes, for example, a transfer bank code, an account number, a transfer amount, and the like in an electronic financial transaction. The request time means the time requested by the client terminal to the service server. This increases the randomness of the integrity code and blocks the predictability of the hacker (see Figure 2)

The integrity code 2100 is generated as described in Equation 3, and the OTP authentication server 300 is responsible for generating the integrity code (see FIG. 3)

In order to generate the one-time password including the integrity code 2100, information on the request request items and the request time are required by the user to the service server. As described above, the service request items in the electronic financial transaction may be, for example, a transfer bank code, a transfer account, a transfer amount, and the like. These service request items are combined and the request time is attached together to define it as the service request data, which becomes the source data for generating the integrity code. Pass the service request data to the hash function H () to obtain the hash result h1. h1 is again passed to the expression function Rep () to generate an integrity code. Since this integrity code is a code for proving the integrity of the service request item and is included as a part of the input value for generating the one time use password (OTP), the one-time password of the present invention can be used to verify the integrity with the service request data on the OTP authentication server side do. The hash input data is completed by combining the integrity code and the serial number of the OTP generator, discretized time data, and other reservation codes. After passing the hash input data to the hash function and expression function, a one-time password containing the final integrity data is generated.

The detailed configuration for generating the one-time password according to the present invention is as follows (see FIG. 1-4)

A system for generating a one-time password comprising an integrity code, or a one-time password generator,

(a) preparing the hash input data 1000 by connecting the integrity code 2100, serial, and discretized time data, and other reservation codes;

(b) inputting the hash input data to the hash function module 411 and deriving a hash result;

(c) inputting the hash result into the expression function module 412 and deriving a one-time password (OTP) 1100. [

The integrity code 2100 generates the service request data by attaching a plurality of service request items and a request time, passes the hash function module 411 and the presentation module 412, and is generated with a predetermined length. The plurality of service request items described above may include a transfer bank code, a transfer account, and a transfer amount considering an electronic financial transaction.

The one-time password authentication method including the integrity code is configured as follows.

(See Authentication Method Embodiment 1, Figures 5 and 7)

A one-time password based authentication method including a client terminal, a service server, an OTP authentication server, and a wired / wireless communication terminal,

(a) The OTP authentication server 300 generates service request data by attaching a plurality of service request items received from the service server 200 and a request time, and generates an integrity code 2100 using the hash function module and the presentation module ;

(b) receiving the service request item and the integrity code from the ARS / SMS server in the wired / wireless communication terminal 600 in which the connection number is registered;

(c) connecting the integrity code, serial, reservation code, and discretized time data to the OTP generator 500 and generating a one-time password using the hash function module and the presentation module;

(d) receiving, by the wired / wireless communication terminal 600, the disposable password and transmitting the disposable password to the ARS / SMS server and transmitting the disposable password to the OTP authentication server;

(e) The OTP authentication server authenticates the one-time password 1100 and informs the service server of the result of the authentication so that the service server selects whether or not to perform the requested service.

This authentication method may be constituted by another embodiment as follows.

(Authentication method example 2, Figs. 6 and 7)

A one-time password based authentication method including a client terminal, a service server, an OTP authentication server, and a wired / wireless communication terminal,

(a) The OTP authentication server 300 generates service request data by attaching a plurality of service request items received from the service server 200 and a request time, and generates an integrity code 2100 using the hash function module and the presentation module ;

(b) receiving the service request item and the integrity code from the ARS / SMS server in the wired / wireless communication terminal 600 in which the connection number is registered;

(c) connecting the integrity code, serial, reservation code, and discretized time data to the OTP generator 500 and generating a one-time password using the hash function module and the presentation module;

(d) the client terminal 100 receives the one-time password and transmits it to the service server 200, and the received service server transmits the one-time password to the OTP authentication server;

(e) The OTP authentication server authenticates the one-time password 1100 and notifies the service server of the result.

Authentication Method In Embodiments 1 and 2, it is determined whether the one-time password generated by using the integrity code received by the wired / wireless communication terminal is transmitted to the OTP authentication server using the client terminal or by using the wired / wireless communication terminal There is a difference. However, since the integrity of the one-time password including the integrity code is verified by the OPT authentication server during the authentication process, the security level is the same regardless of the path.

The most important application of the one-time password-based authentication method including the integrity data of the present invention is electronic payment related fields such as internet banking and phone banking, and the existing challenge-response or time-sinking one- The possibility of an attack that could not be done can be completely blocked.

The OTP generator 500 is implemented as a portable terminal having a specific configuration as follows (see FIG. 4). An input unit 550 for receiving the received integrity code 2100, a memory unit 530 for storing serial and reservation codes, a hash unit 510 for generating a hash result, a time- A control unit 540 for generating hash input data by adding the hash code 520, the integrity code 2100, the serial, the discretized time data, and other reservation codes to the hash unit 510 to generate a one- And a display unit 560 for displaying the image.

This authentication method is implemented including the following components (see Figs. 1 and 7).

A service server 200 that receives a service request of the client terminal 100 and provides an authenticated service, a service server 200 that generates an integrity code 2100 by combining the service request item and the request time, An OTP authentication server 300 for authenticating a password,

An SMS / ARS server 400 receiving the integrity code and the one-time password and transmitting the same to the OTP authentication server,

A one-time password generator 500 for generating a one-time password including an integrity code by connecting the wired / wireless communication terminal 600 receiving the integrity code, the entered integrity code 2100, the serial, the discretized time data, Is included to constitute an authentication system.

1 is a conceptual diagram illustrating an authentication method of a disposable cryptosystem including an integrity code according to an embodiment of the present invention.

FIG. 2 illustrates a method of generating an integrity code according to an embodiment of the present invention.

FIG. 3 illustrates a method of generating a one-time password using an integrity code according to an embodiment of the present invention.

FIG. 4 illustrates a configuration of a one-time password generator using an integrity code according to an embodiment of the present invention.

FIG. 5 shows a flow of a protocol in which each object transmits and receives a one-time password-based authentication method using an integrity code according to an embodiment of the present invention.

FIG. 6 shows a flow of a protocol in which each object sends and receives a one-time password-based authentication method using an integrity code according to an embodiment of the present invention.

FIG. 7 illustrates a screen of a service request item and an integrity code received using SMS according to an embodiment of the present invention. The transmission of the integrity code can be similarly transmitted to the wired communication terminal using the ARS.

Claims (9)

A system for generating a one-time password comprising an integrity code, or a one-time password generator, (a) generating service request data by connecting a service request item 1, a service request item 2, ..., a service request item N, and a service request time with a single string; (b) passing the service request data to a hash function module 411 and an expression function module 412 to generate an integrity code 2100; (c) generating the hash input data 1000 by concatenating the integrity code 2100, the serial, the discretized time data, and the reservation code into one string; (d) inputting the hash input data to the hash function module 411 and deriving a hash result; (e) inputting the hash result into an expression function module (412) and deriving a one-time password (OTP) (1100). delete The method according to claim 1, Wherein the plurality of service request items include a transfer bank code, a transfer account, and a transfer amount in an electronic financial transaction. A one-time password based authentication method including a client terminal, a service server, an OTP authentication server, and a wired / wireless communication terminal, (a) The OTP authentication server 300 generates service request data by attaching a plurality of service request items received from the service server 200 and a request time, and generates an integrity code 2100 using the hash function module and the presentation module ; (b) receiving the service request item and the integrity code from the ARS / SMS server in the wired / wireless communication terminal 600 in which the connection number is registered; (c) connecting the integrity code, serial, reservation code, and discretized time data to the OTP generator 500 and generating a one-time password using the hash function module and the presentation module; (d) receiving, by the wired / wireless communication terminal 600, the disposable password and transmitting the disposable password to the ARS / SMS server and transmitting the disposable password to the OTP authentication server; (e) Authenticating the one-time password (1100) by the OTP authentication server and notifying the result to the service server. A one-time password based authentication method including a client terminal, a service server, an OTP authentication server, and a wired / wireless communication terminal, (a) The OTP authentication server 300 generates service request data by attaching a plurality of service request items received from the service server 200 and a request time, and generates an integrity code 2100 using the hash function module and the presentation module ; (b) receiving the service request item and the integrity code from the ARS / SMS server in the wired / wireless communication terminal 600 in which the connection number is registered; (c) connecting the integrity code, serial, reservation code, and discretized time data to the OTP generator 500 and generating a one-time password using the hash function module and the presentation module; (d) the client terminal 100 receives the one-time password and transmits it to the service server 200, and the received service server transmits the one-time password to the OTP authentication server; (e) Authenticating the one-time password (1100) by the OTP authentication server and notifying the result to the service server. An input unit 550 for receiving the received integrity code, a memory unit 530 for storing serial and reservation codes, a hash unit 510 for generating a hash result, a time discretization unit 520 for generating discretized time data, A control unit 540 for generating hash input data by combining the integrity code 2100, the serial, the discretized time data, and the reservation code, and transmitting the generated hash data to the hash unit 510 to generate a one-time password, (560). ≪ RTI ID = 0.0 > 5. < / RTI > A service server 200 that receives a service request of the client terminal 100 and provides an authenticated service, a service server 200 that generates an integrity code 2100 by combining the service request item and the request time, An OTP authentication server 300 for authenticating a password, An SMS / ARS server 400 receiving the integrity code and the one-time password and transmitting the same to the OTP authentication server, A one-time password generator 500 for generating a one-time password including an integrity code by connecting the wired / wireless communication terminal 600 receiving the integrity code, the entered integrity code 2100, the serial, the discretized time data, A user authentication system using a one-time password including an integrity code. A computer-readable recording medium having recorded thereon a program for executing the one-time password generation method including the integrity code (2100) of claim 1. A computer-readable recording medium having recorded thereon a program for executing an authentication method using a one-time password including the integrity code (2100) according to any one of claims 4 to 5.

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