JP3498008B2 - User mutual authentication system, user mutual authentication method, and recording medium - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a user mutual authentication system, a user mutual authentication method and a recording medium using a cryptographic method, and more particularly to a client / server in which a client and a server are connected via the Internet or an intranet. The present invention relates to a user mutual authentication system, a user mutual authentication method, and a recording medium.

[0002]

2. Description of the Related Art In a client / server system via the Internet or an intranet, a conventional technique for speeding up mutual user authentication using encryption between a client and a server is as follows, for example.

At the time of the first connection from the client to the server, mutual authentication is performed by mutually encrypting and exchanging the random number for authentication and the common key information using the public keys of the other parties, and how to perform the subsequent communication. Both parties decide whether to use a random number for authentication and a common key. The random number for authentication and the common key are stored in the storage means on the client and server sides. When connecting the same client and server for the second time and thereafter, the stored random numbers for authentication are encrypted with a common key and exchanged to mutually authenticate each other.

[0004]

The problem of the above-mentioned conventional technique is that the common key is not updated, so that the same common key is continuously used for the connection between the same client and the server after the second time, and the same common key is used. This means that the common key will continue to be used for a long time, and there is a high possibility that the common key will be intercepted (decrypted).

An object of the present invention is to solve the above-mentioned drawbacks and to realize highly reliable mutual user authentication by updating a common key.

[0006]

According to a first mutual user authentication system of the present invention , an initial authentication start token is added to an index section.
The second key that stores the second authentication information in the data section.
With a cache table, the initial authentication start token
The first authentication response token to the
Send second authentication response token for certificate start token
The server that receives the authentication response completion token.
The user ID of the server is stored in the query section and the first in the data section.
A first cache table for storing authentication information,
The initial authentication start token requesting authentication for the first time, twice
Authentication start talk from the second time onward requesting authentication
Send the authentication response completion token indicating the completion of authentication
A client to
The user ID of the server in the first cache table
Check whether the first authentication information corresponding to
If the search is performed and the search fails, the generation information Ka is generated and generated.
The initial authentication start token including the information Ka is sent to the server.
And sends the generated information Kb and the random number R1 from the server.
When receiving the first authentication response token, the random number R2
To generate a common key from the generation information Ka and the generation information Kb.
Including the random number R2 generated and encrypted with the generated common key
The authentication response completion token is transmitted to the server, and the first
Corresponding to the user ID of the server in the cache table of
Random number R1, random number R2, and generated common key in the data section
Storing the first authentication information including the first cache information;
If the lookup table is successfully searched, a random number R3 is generated and
Encrypted with the common key from the first cache table
Random number R3, R2 from the first cache table,
Authentication starting from the second time including the initial authentication start token
Send the start token, and the server sends random numbers R1 and R
When receiving the second authentication response token containing 4,
Number R3, random number R4 from the second authentication response token
Generate a new common key from the first cache table
The first of the data part corresponding to the user ID of the server
Random number R1, random number R2, and common key of authentication information of
Replace with the number R4, random number R3, new common key, and the server
When the initial authentication start token is received, a random number R1
Before generating the generation information Kb and including the random number R1 and the generation information Kb
The first authentication response token is transmitted, and the generation information Kb, before
Common key from the generation information Ka from the initial authentication start token
Is generated, and when the authentication response completion token is received,
Decrypted with the generated common key, and the second cache table
The initial authentication token in the index part of the
The second number including the random number R1, the random number R2, and the generated common key
Authentication information is stored, and the authentication start token from the second time onwards
To the second cache table,
The initial start confirmation included in the authentication start token after the second time
Whether the second authentication information corresponding to the identification token exists
If the search is successful, and if the search is successful,
The random number R2 in the cache table and the authentication starting from the second time
When the random number R2 in the first token matches, the random number R4 is generated.
Created by using the common key from the second cache table.
Encrypted random number R4 from the second cache table
Sending the second authentication response token containing R1 of
Generated random number R4, from the authentication start token from the second time onwards
Generate a new common key from the random number R3 of
Table corresponding to the initial authentication start token
Common random number R1, random number R2 of the second authentication information
Replace key with random number R4, random number R3, new common key respectively
It

A second mutual user authentication system of the present invention is the first mutual user authentication system, wherein:
Receiving the second authentication response token from the server,
The first cache table is searched successfully, and the second cache table is searched.
Of the random number R1 included in the authentication response token of
If the random number R1 in the cache table does not match,
If the authentication is not established, the first cash
Delete the corresponding first authentication information in the
Have a client.

A first mutual user authentication method of the present invention is
Initial authentication start token in the index part and data part
A second cache table that stores the second authentication information
A first authentication response to the initial authentication start token.
Answer token, or authentication start token from the second time onwards
Send the second authentication response token to
The server that receives the Khun and the server in the index section
User ID of the first authentication information is stored in the data section
Has a first cache table and requires authentication for the first time
The initial authentication start token, which requires authentication after 2 times
The second and subsequent authentication start tokens, which indicate the completion of authentication
A client that sends the authentication response completion token
And the client uses the first cache
Table corresponding to the user ID of the server.
Steps to search for the presence of authentication information, and
If the search fails, the generation information Ka is generated and the generation information Ka is generated.
Sending the initial authentication start token including
And the generation information Kb and the random number R1 from the server.
When receiving the first authentication response token including
R2 is created, and the common key is created from the generation information Ka and the generation information Kb.
And includes a random number R2 encrypted with the generated common key
A step of transmitting the authentication response completion token to the server.
Of the server of the first cache table
Random number R1, random number R2, in the data section corresponding to the user ID,
A storage for storing the first authentication information including the generated common key.
Succeeded in searching the first cache table with the step
Then, a random number R3 is generated, and the first cache data is generated.
The random number R3 encrypted with the common key from the
R2 from the cache table, the initial authentication start talk
The authentication start token that is sent from the second time onward
Before including the random numbers R1 and R4 from the server
When receiving the second authentication response token, the random number R3,
The new common key from the random number R4 from the second authentication response token
Generating the server of the first cache table
First authentication information of the data portion corresponding to the user ID of
Random number R1, random number R2, common key is random number R4, random
The number R3, the step of replacing with a new common key, and the server
When the initial authentication start token is received, a random number R
1. Generate the generation information Kb and generate the random number R1 and the generation information Kb.
Sending the first authentication response token including
And the generation information Kb, the raw from the initial authentication start token.
Generating a common key from the generated information Ka, and the authentication
When the response completion token is received, it is decrypted with the generated common key
In the index section of the second cache table
The initial authentication token has a random number R1 and a random number R in the data part.
2. Store the second authentication information including the generated common key
However, if the authentication start token is received after the second time,
In the second cache table, the second and subsequent authentications are opened.
Corresponding to the initial start authentication token included in the start token
Searching for the presence of the second authentication information
If the search is successful, in the second cache table
Random number R2 and randomness in the authentication start token after the second time
When the number R2 matches, a random number R4 is generated and the second
Random number R encrypted with common key from cache table
4, before including R1 from the second cache table
The step of transmitting the second authentication response token and the generation
Random number R4 from the authentication start token
A new common key is generated from the random number R3, and the second cache is used.
Data corresponding to the initial authentication start token in the table
Part of the second authentication information random number R1, random number R2, common key
Are replaced by random number R4, random number R3, and new common key, respectively.
Includes a step, a.

A second mutual user authentication method of the present invention is the first mutual user authentication method, wherein the client
Receives the second authentication response token from the server.
Received and successfully searched the first cache table
The random number R1 included in the second authentication response token.
And the random number R1 in the first cache table do not match.
If they match, it is determined that the authentication is not established, and the first
The corresponding first authentication information in the cache table
Including the step of deleting.

A first recording medium of the present invention is an index
Initial authentication start token in the data section and the second authentication in the data section
A second cache table for storing information,
First authentication response talk for initial authentication start token
Or the second for the authentication start token after the second time
Send the authentication response token of
User of the server to receive server and index part
The ID is the first key that stores the first authentication information in the data section.
The first with a cache table and requiring authentication for the first time
Term authentication start token, the above 2 which requires authentication after the second time
Authentication start token after the first time, the above authentication indicating the completion of authentication
Use a client that sends a response completion token,
User I of the server in the first cache table
Whether the first authentication information corresponding to D exists
The step of searching and the generation information Ka if the search fails
And the initial authentication start talk including the generation information Ka.
From the server,
The first authentication response token including the generation information Kb and the random number R1.
When Kun is received, the random number R2 is created and the generation information Ka,
A common key is generated from the generation information Kb, and the generated common key
The authentication response completion token including the encrypted random number R2
Sending to the server, the first cache
Data part of the table corresponding to the user ID of the server
The random number R1, the random number R2, and the generated common key
Storing authentication information of the first cache,
If the lookup table is successfully searched, a random number R3 is generated and
Encrypted with the common key from the first cache table
Random number R3, R2 from the first cache table,
Authentication starting from the second time including the initial authentication start token
Sending the first token and a random number from the server
Receive the second authentication response token including R1 and random number R4
When receiving, from the random number R3, the second authentication response token
A new common key is generated from the random number R4 of
Data corresponding to the user ID of the server in the user table
Part of the first authentication information random number R1, random number R2, common key
Are replaced by random number R4, random number R3, and new common key, respectively.
The initial authentication is performed by the client executing the steps
When the start token is received, the random number R1 and the generation information Kb are
The first authentication generated and including the random number R1 and the generation information Kb
The step of transmitting a response token and the generation information Kb, before
Common key from the generation information Ka from the initial authentication start token
Is generated, and the authentication response completion token is received.
Then, it decrypts with the generated common key,
The initial authentication token is added to the index section of the stable.
The random number R1, the random number R2, and the generated common key in the data part.
The second authentication information including the authentication information is stored, and the second and subsequent authentications are performed.
When the start token is received, the second cash
Bull, before being included in the authentication start token after the second time
The second authentication information corresponding to the initial start authentication token
Is searched for, and if the search is successful, the previous
The random number R2 in the second cache table and
If the random number R2 in the authentication start token after the eyes matches,
Generate a random number R4 from the second cache table
Random number R4 encrypted with the common key of the second cache
The second authentication response token containing R1 from the table
And a random number R4 generated, the second time
After that, a new common key is generated from the random number R3 from the authentication start token.
And the initial authentication of the second cache table is opened.
Of the second authentication information of the data part corresponding to the start token
Random number R1, random number R2, common key random number R4, random number respectively
R3, replacing with the new common key, to the server
Record the program you want to run .

A second recording medium of the present invention is the first recording medium, comprising the second authentication response from the server.
The answer token is received and stored in the first cache table.
Successful search, included in the second authentication response token
Random number R1 and random number R in the first cache table
If 1 does not match, authentication is not established, and
The corresponding first authorization in the first cache table.
Cause the client to perform the step of deleting the authentication information .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a client / server system to which the present invention is applied will be described with reference to the drawings. FIG. 2A shows a client to which the present invention is applied.
It is a block diagram which shows a server system, FIG.
FIG. 3 is an explanatory diagram of a communication sequence in FIG. 1.

Referring to FIG. 2A, in the client / server system to which the invention is applied, a plurality of clients 1 and a plurality of servers 2 are connected via a network 3 such as the Internet or an intranet. In this client / server system, when an arbitrary client 1 and an arbitrary server 2 authenticate each other and send / receive data to / from the authenticated other party, the procedure as shown in FIG. 2B is taken. .

First, the connection connection phase is executed, and the network 3 is provided between the client 1 and the server 2.
Connect the connection via. Next, the mutual authentication phase is executed, the client 1 side confirms that the server 2 of the connection partner is the server that truly wants to connect, and that the client 1 of the connection partner is the client that truly wants to connect. The server 2 side confirms. Then, the data transfer phase is executed only when mutual authentication is possible, data is transmitted and received between the client 1 and the server 2, and after the series of data transfer phases is completed, the connection disconnection phase is executed to establish the connection. Disconnect. If mutual authentication is not obtained in the mutual authentication phase, the connection disconnection phase is immediately executed without shifting to the data transfer phase. When the client 1 connects to the server 2 again, each phase of connection connection, mutual authentication, data transfer, and connection disconnection is repeated.

The mutual user authentication of the present invention is applied to the mutual authentication phase in the above communication sequence.

Next, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 shows the first of the present invention.
It is a block diagram showing an embodiment of. Referring to FIG. 1, a first exemplary embodiment of the present invention includes a client 1 and
It is composed of a server 2 and a network 3 connecting these. The client 1 and the server 2 have an authentication unit 10 and an authentication unit 20, respectively, and in the mutual authentication phase after connection connection, mutual authentication processing is performed by the authentication unit 10 and the authentication unit 20, and mutual authentication is possible. The subsequent data transfer phase is carried out only in the case.

The authentication unit 10 of the client 1 stores the authentication information cache table 11, a storage unit 17, an authentication information cache search unit 12, an authentication start token generation / transmission unit 13, and an authentication response token reception unit 14.
And an authentication response completion token generation / transmission means 15 and an authentication information cache generation / update means 16. Such an authentication unit 10 can be realized by a computer having a processor (CPU) and a memory and a machine-readable recording medium such as a CD-ROM, a magnetic disk device, and a semiconductor memory. In this case, a program for mutual authentication on the client 1 side is recorded on the recording medium, and the program is read by the CPU and the operation of the CPU is controlled, whereby the authentication unit 1 is installed on the client 1.
Achieve 0.

On the other hand, the authentication unit 20 of the server 2 stores the authentication information cache table 21, a storage unit 27, an authentication start token reception unit 22, an authentication information cache search unit 23, and an authentication response token generation / transmission unit 24.
And an authentication response completion token receiving means 25 and an authentication information cache generation / update means 26. Such an authentication unit 20 can be realized by a computer having a processor (CPU) and a memory and a machine-readable recording medium such as a CD-ROM, a magnetic disk device, and a semiconductor memory. In this case, a program for mutual authentication on the server 2 side is recorded on the recording medium, and the program is read by the CPU and the operation of the CPU is controlled to realize the authentication unit 20 on the server 2.

Next, each component of the authentication unit 10 of the client 1 will be described. FIG. 3 is an explanatory diagram showing the configuration of the authentication information cache table 11. The authentication information cache table 11 is a table that holds the authentication information of the server 2 of the connection partner, and is dynamically generated for each server 2 at the time of the first connection. Referring to FIG. 3, the authentication information cache table 11 includes an index part and a data part, and the index part includes a user I of the server 2 in the index part.
D is registered and an initial authentication start token encrypted with the public key of the server 2, a user ID of the client 1, a random number R1 (generated by the server 2), a random number R2 in the data part.
(Generated by client 1), set of authentication information (public key of server 2, user ID of server 2, client 1
Private key, common key, etc.) are registered.

The authentication information cache retrieving means 12 is means for retrieving the authentication information cache table 11 having the user ID of the server 2 in the index portion from the storage means 17 at the start of the authentication phase.

The authentication start token generating / transmitting means 13 is
This is a means for generating an initial authentication start token or an authentication start token for the second and subsequent times according to the search result of the authentication information cache search means 12 and transmitting it to the server 2. The initial authentication start token is generated and transmitted when the search fails, and the second and subsequent authentication start tokens are generated and transmitted, respectively.

Next, the contents of the initial authentication start token and the second and subsequent authentication start tokens will be described. Figure 4
FIG. 4A is an explanatory diagram showing the contents of the periodic authentication start token, and FIG. 4B is an explanatory diagram showing the contents of the authentication start token for the second and subsequent times.

Referring to FIG. 4A, the term authentication start token is a header including a token indicating that the token is an initial authentication start token, a user ID of the client 1 encrypted by the public key of the server 2, and a random number. Ra and common key first
It includes the generation information seed-Ka. The public key of the server 2 is obtained by the client 1 in advance and separately managed. As the public key method, for example, RSA can be used. The random number Ra and the first generation information seed-Ka of the common key are independently generated by the random number generator in the authentication start token generation / transmission means 13. Common key first generation information seed-Ka
Is information that can uniquely generate one common key by combining it with second generation information seed-Kb of the common key, which will be described later and is generated on the server 2 side. That is, when the information A and the information B are determined, a specific common key is generated from them, and when no other common key can be generated, such information A and B is the first generation information of the common key. seed-Ka, common key second generation information seed
-Kb. As the common key method, for example, DE
S can be used.

Referring to FIG. 4 (b), the authentication start token for the second and subsequent authentications is a header including the fact that the token is the authentication start token for the second and subsequent authentications, and the initial authentication encrypted with the public key of the server 2. It contains a start token and a random number R2 and a random number R3 encrypted with a common key. The initial authentication start token is the initial authentication start token acquired from the retrieved authentication information cache table 11. The random number R2 is obtained from the retrieved authentication information cache table 11. The random number R3 is newly generated by the authentication start token generating / transmitting means 13 by the random number generator. The common key for encrypting the random numbers R2 and R3 is the common key acquired from the retrieved authentication information cache table 11.

The authentication response token receiving means 14 is means for receiving and processing an authentication response token when the server 2 has transmitted the authentication start token transmitted by the authentication start token generating / transmitting means 13. . There are two types of authentication response tokens to be received: an initial authentication response token and an authentication response token from the second time onward.

Next, the initial authentication response token and the second and subsequent authentication response tokens will be described. Figure 5 (a)
Is an explanatory diagram showing the contents of the initial authentication response token, FIG.
(B) is an explanatory view showing the contents of the authentication response token from the second time onward.

Referring to FIG. 5 (a), the initial authentication response token includes a header containing a token indicating that the token is an initial authentication response token, a random number Ra and a random number Rb encrypted with the public key of the client 1, and a common Second key generation information se
ed-Kb and random number R1 (or random number Rn) are included.

Referring to FIG. 5B, the second and subsequent authentication response tokens include a header including the fact that the token is the second and subsequent authentication response tokens, and a random number R4 and a random number R1 encrypted with a common key. Is included. The second and subsequent authentication response tokens are returned as the second and subsequent authentication start token responses, but the initial authentication response token may be returned as the second and subsequent authentication start token responses in addition to the initial authentication start token response. The method for generating the initial identification response token and the authentication response tokens for the second and subsequent times will be described in detail in the description of the authentication response token generation / transmission means 24 of the server 2.

Authentication response completion token generation / transmission means 15
When the authentication response token receiving means 14 receives the initial authentication response token, is a means for generating an authentication response completion token, which is a response to the initial authentication response token, and transmitting it to the server 2. When the authentication response token receiving means 14 receives the authentication response token from the second time onward, the authentication response completion token generating / transmitting means 15 does not operate.

Next, the authentication response completion token will be described. FIG. 6 is an explanatory diagram showing the content of the authentication response completion token. Referring to FIG. 6, the authentication response completion token includes a header including that the token is an authentication response completion token, and random numbers Rb and R2 encrypted with a common key.
(Or random number Rn + 1). The random number Rb is extracted from the initial authentication response token received by the authentication response token receiving means 14, and is a random number R2 (or Rn).
+1) is uniquely generated by the authentication response completion token generation / transmission means 15 by the random number generator. The common key for encrypting these is the first generation information seed-Ka of the common key included in the initial authentication start token sent by the authentication start token generation / transmission means 13 and the authentication response token reception means 14 for the initial authentication response. It is a common key uniquely generated from the second generation information seed-Kb of the common key extracted from the token.

Authentication information cache generation / update means 16
Are means for registering information in the authentication information cache table 11 as shown in FIG. 3 in the storage means 17, updating information in the authentication information cache table 11 already registered, and deleting.

Next, each component of the authentication unit 20 of the server 2 will be described. FIG. 7 is an explanatory diagram showing the configuration of the authentication information cache table 21. The authentication information cache table 21 is a table holding the authentication information of the client 1 of the connection partner, and is dynamically generated for each client 1 at the time of the first connection. Referring to FIG. 7, the authentication information cache table 21 includes an index part and a data part, and the index part includes the server 2
The initial authentication start token encrypted with the public key of is registered in the data part, the user ID of the server 2, the random number R1 (generated by the server 2), the random number R2 (generated by the client 1), the authentication information. Complete set (client 1's public key,
The user ID of the client 1, the secret key of the server 2, the common key, etc.) are registered.

The authentication start token receiving means 22 is means for receiving the authentication start token from the client 1 at the start of the authentication phase. The authentication start token to be received includes the initial authentication start token shown in FIG.
There are two types of authentication start tokens after the second time shown in (b).

When the authentication start token receiving means 22 receives the authentication start token from the second time onward, the authentication information cache searching means 23 has the authentication information having the initial authentication start token included in the authentication start token from the second time onward in the index part. It is means for searching the cache table 21 from the storage means 27. When the authentication start token receiving means 22 receives the initial authentication start token, the authentication information cache searching means 23 does not operate.

The authentication response token generation / transmission means 24 is
An authentication response token is generated as a response to the authentication start token received by the authentication start token receiving means 22,
It is a means for transmitting to the client 1. There are two types of authentication response tokens to be generated and transmitted: the initial authentication response token and the second and subsequent authentication response tokens. For the second and subsequent authentication response tokens, the authentication start token receiving unit 22 receives the authentication start token for the second and subsequent times, and the authentication information cache search unit 23 succeeds in searching the authentication information cache table 21 and further authentication is established on the server 2 side. Generated and sent when you do. In the case of the initial authentication response token other than that, that is, when the initial authentication start token is received by the authentication start token receiving means 22, the authentication start token is received for the second time and thereafter, but the authentication information cache table 21.
If the search fails, or if the search is successful but the authentication is not established, it is generated and transmitted.

Next, the authentication response token will be described. Referring to FIG. 5A, in the initial authentication response token, the random number Ra is extracted from the random number Ra extracted from the initial authentication start token received by the authentication start token receiving means 22 or the searched authentication information cache table 21. It is the random number Ra in the generated initial authentication start token. Also, the random number Rb and the second generation information seed-Kb of the common key
And the random number R1 are the authentication response token generation / transmission means 2
4 is uniquely generated by the random number generator. Further, the public key of the client 1 that encrypts these is a public key that the server 2 previously acquired and separately managed.

Referring to FIG. 5B, the random number R1 in the authentication response token from the second time onward is extracted from the retrieved authentication information cache table 21, and the random number R1.
Reference numeral 4 is generated by the authentication response token generation / transmission means 24 by the random number generator, and the common key for encrypting them is the retrieved authentication information cache table 2
This is the common key acquired from 1.

When the authentication response token generating / transmitting means 24 transmits the initial authentication response token, the authentication response completion token receiving means 25 sends the authentication response completion token as shown in FIG. It is a means for receiving and processing from. When the authentication response token generation / transmission means 24 transmits the authentication response token for the second time and thereafter, the authentication response completion token reception means 25 does not operate.

Authentication information cache generation / update means 26
Is means for newly registering information in the authentication information cache table 21 as shown in FIG. 7 in the storage means 27, updating information in the already registered authentication information cache table 21, or deleting. .

Next, the operation of the first embodiment of the present invention will be described with reference to the drawings. FIG. 8 shows the first of the present invention.
3 is a flowchart showing the operation of the embodiment of FIG. Figure 9
~ FIG. 12 is an explanatory diagram showing an authentication flow of the operation according to the first embodiment of the invention.

First, the case where the search of the authentication information cache table 11 of the client 1 fails (that is, the information is not registered) will be described.

In the client 1, the authentication information cache search means 12 uses the authentication information cache table 11
When the information of the server 2 is searched using the user ID of the server 2 as a key (FIG. 8S1), and the search fails (S1 failure in FIG. 8), the authentication flow as shown in FIG. 9 is performed.

The client 1 uses the authentication start token generation / transmission means 13 to generate the random number Ra and the first generation information seed-Ka of the common key, and then the own user ID, the random number Ra,
And the first generation information seed-Ka of the common key is encrypted with the public key of the server 2, and the initial authentication start token (FIG. 9f1) including the same is transmitted to the server 2 (S2 in FIG. 8).

The server 2 receives the initial authentication start token (FIG. 9f1) from the client 1 as the authentication start token receiving means 2
2, the initial authentication start token is decrypted with the self-secret key, and the random number Ra and the first generation information seed of the common key are received.
-Ka is extracted (Fig. 8 S3).

Next, in the server 2, the authentication response token generation / transmission means 24 generates the random number Rb, the random number R1, and the second generation information seed-Kb of the common key, and the random number Ra,
Random number Rb, random number R1, and second generation information s of common key
The eed-Kb is encrypted with the public key of the client 1, and the authentication response token (FIG. 9f2) including it is transmitted to the client 1 (S4 in FIG. 8). Further, the first generation information seed-Ka of the common key and the second generation information seed of the common key
A common key is generated from d-Kb (S5 in FIG. 8).

The client 1 uses the authentication response token receiving means 14 to send the authentication response token from the server 2 (see FIG. 9f).
2) is received, the received authentication response token is decrypted by the private key, and the random number Ra, the random number Rb, the random number R1, and the second generation information seed-Kb of the common key are extracted (FIG. 8S).
6). Furthermore, the first generation information seed-K of the common key
a, a common key is generated from the second generation information seed-Kb of the common key (S7 in FIG. 8).

Next, in the client 1, the authentication response completion token generation / transmission means 15 generates a random number R2, encrypts the random number Rb and the random number R2 with the generated common key, and includes the authentication response completion token ( 9g1) server 2
(S8 in FIG. 8).

Next, the client 1 uses the authentication information cache generating / updating means 16 to store the user ID of the server 2 in the index portion of the authentication information cache table 11.
In the data part, the initial authentication start token encrypted with the public key of the server 2, the user ID of the client 1, the random number R
1, a random number R2, and a set of authentication information (public key of server 2, user ID of server 2, secret key of client 1, common key, etc.) are registered as a pair (FIG. 8S9).

When the authentication response completion token receiving means 25 of the server 2 receives the authentication response completion token (FIG. 9g1), the server 2 decrypts the authentication response completion token with the previously generated common key to extract the random number Rb and the random number R2 (see FIG. 8S10).

Next, in the server 2, the authentication information cache generating / updating means 26 deletes the information of the client 1 if it exists in the authentication information cache table 21,
An initial authentication start token encrypted with the public key of the server 2 is stored in the index section, and a user I of the server 2 is stored in the data section.
D, random number R1, random number R2, and a set of authentication information (public key of client 1, user ID of client 1, secret key of server 2, common key, etc.) are registered as a pair (FIG. 8S1).
1).

Next, the case where the search of the authentication information cache table 11 of the client 1 and the authentication information cache table 21 of the server 2 is successful (that is, information has been registered) will be described.

In the client 1, the authentication information cache retrieval means 12 uses the authentication information cache table 11
When the information of the server 2 is searched using the user ID of the server 2 as a key (FIG. 8S1) and the search is successful (S1 success in FIG. 8), the authentication flow as shown in FIG. 10 is performed.

Next, the client 1 uses the authentication start token generation / transmission means 13 to generate a random number R3 to be used in the next authentication confirmation, and uses the random number R2 and the random number R3 registered in the authentication information cache table 11 in common. The second and subsequent authentication start tokens including the one encrypted with the key and the initial authentication start token encrypted with the public key of the server 2 registered in the authentication information cache table 11 (see FIG. 10).
g2) is transmitted to the server 2 (S32 in FIG. 8).

The server 2 uses the authentication start token receiving means 2
At 2, the second and subsequent authentication start tokens (FIG. 10g2) are received (FIG. 8S33), and the public key of the server 2 in the second and subsequent authentication start tokens (FIG. 10g2) received by the authentication information cache generating / updating means 26 is used. The authentication information cache table 21 is searched by using the encrypted initial authentication start token portion as a key (S34 in FIG. 8). If the search is successful (S34 in FIG. 14), the authentication information cache table 21
It is confirmed that the random number R2 registered in (1) and the random number R2 in the authentication start token (FIG. 10g2) decrypted and extracted with the common key match (S35 in FIG. 8).

When the random numbers R2 match (S35 in FIG. 8), the authentication response token generation / transmission means 24 generates a random number R4 which is a seed for generating the common key used in the next authentication confirmation, and the generated random number R4 The random number R1 from the authentication information cache table 21 is encrypted with the common key, and the authentication response token (FIG. 10g3) including it is transmitted to the client 1 (S36 in FIG. 8). Also, the random number R4 and the random number R3 extracted from the authentication start token (FIG. 10g2) after the second time.
Based on and, a new common key used in the next authentication confirmation is generated (S37 in FIG. 8).

Next, in the server 2, the authentication information cache generating / updating means 26 causes the authentication information cache table 21.
Update the information in. That is, the random number R1 serving as a seed for generating the common key used in the next authentication confirmation
4. Random number R2 used in the next authentication confirmation in R4
Then, the common key is updated to the new common key used in the next authentication confirmation (S38 in FIG. 8).

The client 1 uses the authentication response token receiving means 14 to send the authentication response token from the server 2 (see FIG. 10g).
3) is received (FIG. 8S39), the received authentication response token (FIG. 10g3) is decrypted with the common key, and the random number R1 in the authentication information cache table 11 and the authentication response token (FIG. 1).
It is confirmed that the random number R1 extracted from 0g3) matches (S40 in FIG. 8).

When it is confirmed that they match (S40 in FIG. 8).
Matching), a new common key used in the next authentication confirmation is generated based on the random numbers R3 and R4 (S41 in FIG. 8).

Next, the client 1 updates the information in the authentication information cache table 11 by the authentication information cache generating / updating means 16. That is, the random number R1 is used as a seed for generating a common key used in the next authentication confirmation, the random number R2 is used as a random number R3 used in the next authentication confirmation, and the common key is used in the next authentication confirmation. The new common key is updated (S42 in FIG. 8).

Next, the search of the authentication information cache table 11 of the client 1 succeeds (that is, the information is registered), and the search of the authentication information cache table 21 of the server 2 fails (that is, the information is registered). If not) will be described. In this case, the authentication flow shown in FIG. 11 is performed.

In the client 1, the authentication information cache search means 12 uses the authentication information cache table 11
The user ID of the server 2 is used as a key to search the information of the server 2 (FIG. 8S1). When the search is successful (S1 success in FIG. 8), the authentication start token generation / transmission means 13 uses the random number used for the next authentication confirmation. R3 is generated and the random number R2 and the random number R3 registered in the authentication information cache table 11 are encrypted with a common key, and the public key of the server 2 registered in the authentication information cache table 11 is encrypted. The second and subsequent authentication start tokens (FIG. 11g2) including the initial authentication start token are transmitted to the server 2 (S32 in FIG. 8).

The server 2 uses the authentication start token receiving means 2
In 2, the second and subsequent authentication start tokens (FIG. 11g2) are received (FIG. 8S33), and the public key of the server 2 in the second and subsequent authentication start tokens (FIG. 11g2) received by the authentication information cache generation / update means 26 is used. The authentication information cache table 21 is searched by using the encrypted initial authentication start token portion as a key (S34 in FIG. 8).

When the search fails (FIG. S34 failure), the initial authentication start token encrypted by the public key of the server 2 of the authentication start token (FIG. 11g2) for the second time and thereafter is decrypted with the private key, and the random number Ra and the common The first generation information seed of the key
Authentication response token generation / transmission means 2 by extracting d-Ka
At 4, the random number Rb, the random number Rn, and the second generation information seed-Kb of the common key are generated, and the second generation information seed-Kb of the random number Ra, the random number Rb, the random number Rn, and the common key is generated as the public key of the client 1. Then, the authentication response token (FIG. 11g4) including the encrypted data is transmitted to the client 1 (S51 in FIG. 8). Furthermore, the first generation information se of the common key
A new common key is generated based on ed-Ka and second generation information seed-Kb of the common key (S52 in FIG. 8).

Next, the server 2 causes the authentication information cache generating / updating means 26 to store the initial authentication start token encrypted in the index part of the authentication information cache table 21 with the public key of the server 2 in the data part. 2 user ID, random number Rn, random number R2, and a set of authentication information (public key of client 1, user ID of client 1, secret key of server 2, new common key, etc.) are registered as a pair (FIG. 8).
S53).

The client 1 uses the authentication response token receiving means 14 to send the authentication response token from the server 2 (see FIG. 11).
g4), and the received authentication response token (Fig. 11g
4) is decrypted with a private key, and a random number Ra, a random number Rb, a random number R
n and the second generation information seed-Kb of the common key are extracted (S54 in FIG. 8).

Further, the first generation information seed of the common key
-Ka, the new common key is generated based on the second generation information seed-Kb of the common key (S55 in FIG. 8).

Next, the client 1 uses the authentication response completion token generation / transmission means 15 to generate a random number Rn + 1,
The random number Rb and the random number Rn + 1 are encrypted with the new common key, and the authentication response completion token (FIG. 11g5) including the same is transmitted to the server 2 (S56 in FIG. 8).

Next, the client 1 updates the information in the authentication information cache table 11 by the authentication information cache generating / updating means 16. That is, the random number R1 is updated to the random number Rn, the random number R2 is updated to the random number Rn + 1, and the common key is updated to the new common key used in the next authentication confirmation (FIG. 8).
S57).

When the authentication response completion token receiving means 25 of the server 2 receives the authentication response completion token (FIG. 11g5), it decrypts this with the new common key and extracts the random number Rb and the random number Rn + 1 (S58 in FIG. 8).

Next, the server 2 updates the information in the authentication information cache table 21 by the authentication information cache generating / updating means 26. That is, the random number R2 is replaced by the random number Rn + 1
Is updated to (S59 in FIG. 8).

Next, the search of the authentication information cache table 11 of the client 1 succeeds (that is, the information is registered), and the search of the authentication information cache table 21 of the server 2 also succeeds (that is, the information is registered). However, the case where the client 1 detects a mismatch in the information in the data section will be described. In this case, the authentication flow shown in FIG. 12 is performed.

In the client 1, the authentication information cache search means 12 uses the authentication information cache table 11
When the information of the server 2 is searched using the user ID of the server 2 as a key (FIG. 8S1) and the search is successful (S1 success in FIG. 8), the client 1 uses the authentication start token generation / transmission means 13 to perform the next authentication. A random number R3 used for confirmation is generated, and the random number R2 and the random number R3 registered in the authentication information cache table 11 are encrypted with a common key.
The second and subsequent authentication start tokens (FIG. 12g2) including the initial authentication start token encrypted with the public key of the server 2 registered in the authentication information cache table 11 are transmitted to the server 2 (S32 in FIG. 8).

The server 2 uses the authentication start token receiving means 2
2, the second and subsequent authentication start tokens (FIG. 12g2) are received (FIG. 8S33), and the second and subsequent authentication start tokens (FIG. 1 S33) received by the authentication information cache generating / updating means 8 are received.
The initial authentication start token portion encrypted by the public key of the server 2 in 2g2) is used as a key to search the authentication information cache table 21 (S34 in FIG. 8). If the search is successful (S34 in FIG. 10 succeeded), the random number R2 registered in the authentication information cache table 21 and the random number R in the authentication start token (FIG. 10g2) after the second decryption extracted by the common key are extracted.
It is confirmed that 2 and 2 match (S35 in FIG. 8).

When the random numbers R2 match (S35 in FIG. 8), the authentication response token generation / transmission means 24 generates a random number R4 which is a seed for generating the common key used in the next authentication confirmation, and the generated random number R4 The random number R1 from the authentication information cache table 21 is encrypted with the common key, and the authentication response token (FIG. 12g3) including it is transmitted to the client 1 (S36 in FIG. 8). Also, the random number R4 and the random number R3 extracted from the authentication start token (FIG. 12g2) after the second time.
Based on and, a new common key used in the next authentication confirmation is generated (S37 in FIG. 8).

Next, the server 2 updates the information in the authentication information cache table 21 by the certificate information cache generating / updating means 26. That is, the random number R4, which is a seed for generating the common key used in the next authentication confirmation, is the random number R4.
And the random number R2 to the random number R3 used in the next authentication confirmation,
The common key is updated to the new common key used in the next authentication confirmation (S38 in FIG. 8).

The client 1 uses the authentication response token receiving means 14 to send the authentication response token from the server 2 (see FIG. 10g).
3) is received (FIG. 8S39), the received authentication response token (FIG. 10g3) is decrypted with the common key, and the random number R1 in the authentication information cache table 11 and the authentication response token (FIG. 1).
It is confirmed that the random number R1 extracted from 0g3) matches (S40 in FIG. 8).

When it is confirmed that they do not match (see FIG. 8S).
40 mismatch), it is considered that mutual authentication has not been established, and the connection disconnection process is executed. That is, the authentication information cache generating / updating means 16 of the client 1 deletes the information of the server 2 in the authentication information cache table 11 (S71 in FIG. 8).

Next, a second embodiment of the present invention will be described with reference to the drawings. In the second embodiment of the present invention, the authentication information cache table 1 of the client 1
1. The user mutual authentication method using the authentication information cache table 21 of the server 2 and the user mutual authentication method including steps S1 to S71 shown in FIG.

Next, a third embodiment of the present invention will be described with reference to the drawings. FIG. 13 is a block diagram showing a third embodiment of the present invention. Referring to FIG. 13, in the third embodiment of the present invention, the steps (S1 to S71 in FIG. 8) of the second embodiment of the present invention are performed by the computer 100 (for example, the client 1 and the server 2). The recording medium 120 records a program to be executed.

Here, this program executes step S
1, S2, S6-89, S32, S39-S42, S5
4 to S57 and S71 are executed by the client 1, and S
3-S5, S10-S11, S33-S38, S51-
The server 2 is configured to execute S53 and S58 to S59.

The program is loaded into the storage devices of the client 1 and the server 2 and further loaded into the main memory for execution.

[0082]

The effects of the present invention are as follows:
The reliability is improved without affecting the performance.

The reason is that the common key is updated for each authentication in the authentication flow (for example, as described above, the random number R3 and the random number R4 are the new common key), so that the common key may be intercepted (deciphered). Is low.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a client / server system to which the present invention is applied, and an explanatory diagram of a communication sequence.

FIG. 3 is an explanatory diagram showing a configuration of a client authentication information cache table.

FIG. 4 is an explanatory diagram showing the contents of an initial authentication start token and second and subsequent authentication start tokens.

FIG. 5 is an explanatory diagram showing the contents of the initial authentication response token and the second and subsequent authentication response tokens.

FIG. 6 is an explanatory diagram showing the content of an authentication response completion token.

FIG. 7 is an explanatory diagram showing a configuration of an authentication information cache table of a server.

FIG. 8 is a flowchart showing an operation of the first exemplary embodiment of the present invention.

FIG. 9 is an explanatory diagram showing an authentication flow of an operation according to the first embodiment of the present invention.

FIG. 10 is an explanatory diagram showing an authentication flow of an operation according to the first embodiment of the present invention.

FIG. 11 is an explanatory diagram showing an authentication flow of an operation according to the first embodiment of the present invention.

FIG. 12 is an explanatory diagram showing an authentication flow of operation according to the first embodiment of the present invention.

FIG. 13 is a block diagram showing a third embodiment of the present invention.

[Explanation of symbols]

1 client 2 servers 3 network 10 Authentication Department 11 Authentication information cache table 12 Authentication information cache search means 13 Authentication start token generation / transmission means 14 Authentication response token receiving means 15 Authentication response completion token generation / transmission means 16 Authentication information cache generation / update means 17 storage means 20 Authentication Department 21 Authentication information cache table 22 Authentication start token receiving means 23 Authentication information cache search means 24 Authentication response token generation / transmission means 25 Authentication response completion token receiving means 26 Authentication Information Cache Generation / Update Means 27 storage means 100 computers 120 recording media

Claims (6)

(57) [Claims] 1. An initial authentication start token is provided in the index section.
Is stored in the data section of the second cache storing the second authentication information.
It is equipped with a stable and supports the initial authentication start token.
1st authentication response token or 2nd authentication
Send a second authentication response token to the start token,
Server and index that receive authentication response completion token
The user ID of the server in the section, and the first authentication in the data section
It has a first cache table for storing information,
Initial authentication start token that requires authentication by 2 times or more
Authentication request token from the second time onwards
Certificate that sends the authentication response completion token indicating completion of the certificate.
A client , wherein the client is the user I of the server in the first cache table.
Whether the first authentication information corresponding to D exists
If the search is performed and the search is unsuccessful, the generation information Ka is generated and the generation information K is generated.
send the initial authentication start token including a to the server
And, generation information Kb from the server, the first containing the random number R1
When the authentication response token of is received, a random number R2 is created,
Generate a common key from the generation information Ka and the generation information Kb, and generate
The authentication response complete including the random number R2 encrypted with the common key
Sends a completion token to the server, user I of the server of the first cache table
Generated a random number R1 and a random number R2 in the data part corresponding to D.
When the first authentication information including the common key is stored and the first cache table is successfully searched, a random number is stored.
Generate a number R3 from the first cache table
A random number R3 encrypted with a common key, the first cache
R2 from the cable, before including the initial authentication start token
Note that the second and later authentication authentication tokens are transmitted, and the second authentication including the random number R1 and the random number R4 is transmitted from the server.
When the certificate response token is received, the random number R3, the second authentication
Generate a new common key from the random number R4 from the certificate response token,
User I of the server in the first cache table
Random number R of the first authentication information in the data portion corresponding to D
1, random number R2, common key is random number R4, random number R3,
When the server replaces with a new common key and the server receives the initial authentication start token, the random number R1
Before generating the generation information Kb and including the random number R1 and the generation information Kb
The first authentication response token is transmitted, and the generation information Kb and the generation information from the initial authentication start token are transmitted.
When a common key is generated from the information Ka and the authentication response completion token is received , the generated common key is generated.
Decrypt with the key and index the second cache table.
The initial authentication token in the box part and the random number R in the data part.
1, the random number R2, the second authentication information including the generated common key
Information and stores the authentication start token after the second time,
In the second cache table, the authentication start
Corresponds to the initial start authentication token included in Kuhn
Search for the presence of the second authentication information, and search
Is successful, the disturbance in the second cache table
Number R2 and random number R in the authentication start token after the second time
When 2 and 2 match, a random number R4 is generated and the second
Random number R4 encrypted with the common key from the cache table, before
The second including R1 from the second cache table
Random number R4 generated by sending the authentication response token of
New common from the random number R3 from the authentication start token from the second time
Generate a key and initialize the second cache table
The second authentication of the data part corresponding to the authentication start token
Random number R1 of information, random number R2, common key respectively
4. A user mutual authentication system characterized by replacement with a random number R3 and a new common key . 2. The second authentication response token from the server
Kun is received and the first cache table is searched for
Successful random number R contained in the second authentication response token
1 and the random number R1 in the first cache table
If they do not match, the first
Corresponding first authentication information in the cache table of
User mutual authentication system according to claim 1, wherein the that have a said client to delete. 3. Initial authentication start token in the index section
Is stored in the data section of the second cache storing the second authentication information.
It is equipped with a stable and supports the initial authentication start token.
1st authentication response token or 2nd authentication
Send a second authentication response token to the start token,
Server and index that receive authentication response completion token
The user ID of the server in the section, and the first authentication in the data section
It has a first cache table for storing information,
Initial authentication start token that requires authentication by 2 times or more
Authentication request token from the second time onwards
Certificate that sends the authentication response completion token indicating completion of the certificate.
Utilizing the client, the client, user I of the server to the first cache table
Whether the first authentication information corresponding to D exists
The step of searching and the generation information Ka when the search fails
send the initial authentication start token including a to the server
And the first information including the generation information Kb and the random number R1 from the server.
When the authentication response token of is received, a random number R2 is created,
Generate a common key from the generation information Ka and the generation information Kb, and generate
The authentication response complete including the random number R2 encrypted with the common key
Sending an end token to the server, and the user I of the server in the first cache table.
Generated a random number R1 and a random number R2 in the data part corresponding to D.
Storing the first authentication information including a common key
If the search of the first cache table is successful,
Generate a number R3 from the first cache table
A random number R3 encrypted with a common key, the first cache
R2 from the cable, before including the initial authentication start token
The step of transmitting an authentication start token after the second time, and the second authentication including the random number R1 and the random number R4 from the server.
When the certificate response token is received, the random number R3, the second authentication
Generate a new common key from the random number R4 from the certificate response token,
User I of the server in the first cache table
Random number R of the first authentication information in the data portion corresponding to D
1, random number R2, common key is random number R4, random number R3,
Replacing with a new common key; and when the server receives the initial authentication start token, a random number R1
Before generating the generation information Kb and including the random number R1 and the generation information Kb
The step of transmitting the first authentication response token, the generation information Kb, and the generation information from the initial authentication start token.
The step of generating a common key from the information Ka and the generated common key when the authentication response completion token is received.
Decrypt with the key and index the second cache table.
The initial authentication token in the box part and the random number R in the data part.
1, the random number R2, the second authentication information including the generated common key
Information and stores the authentication start token after the second time,
In the second cache table, the authentication start
Corresponds to the initial start authentication token included in Kuhn
Search for the presence of the second authentication information, and search
Is successful, the disturbance in the second cache table
Number R2 and random number R in the authentication start token after the second time
When 2 and 2 match, a random number R4 is generated and the second
Random number R4 encrypted with the common key from the cache table, before
The second including R1 from the second cache table
The step of transmitting the authentication response token, and the generated random number R4, whether the authentication start token is the second time or later.
A new common key is generated from the random number R3 from
Corresponding to the initial authentication start token of the stable
The random number R1 and the random number R2 of the second authentication information of the data unit
Replace the common key with random number R4, random number R3, and new common key, respectively
And a user mutual authentication method comprising the steps of :. 4. The client is in front of the server.
The second authentication response token is received, and the first CAP is received.
Succeeded in the table search, and the second authentication response
The random number R1 included in the
If the random number R1 in the bull does not match, the authentication fails.
If there is a corresponding one in the first cache table,
4. The user mutual authentication method according to claim 3, further comprising the step of deleting the first authentication information . 5. An initial authentication start token is provided in the index section.
Is stored in the data section of the second cache storing the second authentication information.
It is equipped with a stable and supports the initial authentication start token.
1st authentication response token or 2nd authentication
Send a second authentication response token to the start token,
Server and index that receive authentication response completion token
The user ID of the server in the section, and the first authentication in the data section
It has a first cache table for storing information,
Initial authentication start token that requires authentication by 2 times or more
Authentication request token from the second time onwards
Certificate that sends the authentication response completion token indicating completion of the certificate.
And a client user I of the server in the first cache table.
Whether the first authentication information corresponding to D exists
The step of searching and the generation information Ka when the search fails
send the initial authentication start token including a to the server
And the first information including the generation information Kb and the random number R1 from the server.
When the authentication response token of is received, a random number R2 is created,
Generate a common key from the generation information Ka and the generation information Kb, and generate
The authentication response complete including the random number R2 encrypted with the common key
Sending an end token to the server, and the user I of the server in the first cache table.
Generated a random number R1 and a random number R2 in the data part corresponding to D.
Storing the first authentication information including a common key
If the search of the first cache table is successful,
Generate a number R3 from the first cache table
A random number R3 encrypted with a common key, the first cache
R2 from the cable, before including the initial authentication start token
The step of transmitting an authentication start token after the second time, and the second authentication including the random number R1 and the random number R4 from the server.
When the certificate response token is received, the random number R3, the second authentication
Generate a new common key from the random number R4 from the certificate response token,
User I of the server in the first cache table
Random number R of the first authentication information in the data portion corresponding to D
1, random number R2, common key is random number R4, random number R3,
Replace the step with the new common key to the client.
It is a row, upon receiving the initial start authentication token, the random number R1, raw
Before generating the generation information Kb and including the random number R1 and the generation information Kb
The step of transmitting the first authentication response token, the generation information Kb, and the generation information from the initial authentication start token.
The step of generating a common key from the information Ka and the generated common key when the authentication response completion token is received.
Decrypt with the key and index the second cache table.
The initial authentication token in the box part and the random number R in the data part.
1, the random number R2, the second authentication information including the generated common key
Information and stores the authentication start token after the second time,
In the second cache table, the authentication start
Corresponds to the initial start authentication token included in Kuhn
Search for the presence of the second authentication information, and search
Is successful, the disturbance in the second cache table
Number R2 and random number R in the authentication start token after the second time
When 2 and 2 match, a random number R4 is generated and the second
Random number R4 encrypted with the common key from the cache table, before
The second including R1 from the second cache table
The step of transmitting the authentication response token, and the generated random number R4, whether the authentication start token is the second time or later.
A new common key is generated from the random number R3 from
Corresponding to the initial authentication start token of the stable
Random number R1 before Symbol second authentication information over data portion, a random number R2, co
Replace the common key with random number R4, random number R3, and new common key, respectively
Recording medium characterized by recording a program for executing the steps that, to the server. 6. The second authentication response packet from the server.
Khun is received and the first cache table is searched
Successful, and the random number included in the second authentication response token
R1 and a random number R1 in the first cache table
If the passwords do not match, the
Corresponding first authentication information in one cache table
The recording medium according to claim 5, wherein the program that causes the client to execute a step of deleting information is recorded.