Message authentication
9 claims: 7 independent, 2 dependent
- 1送信側装置と受信側装置との間の データ通信を認証するデータ認証方法において、 乱数データ、時間的有効性情報、及び私用キーに基づいて、キーハッシュ法によりログインキーを生成するステップと、 上記ログインキーを上記送信側装置から上記受信側装置に伝送するステップと、 上記受信側装置において、キーハッシュダイジェストに基づいて、上記ログインキーの認証有効性及び時間的有効性を確認するステップと、 上記ログインキーの認証有効性及び時間的有効性が確認されると、第2の乱数データと私用キーとに基づいて、キーハッシュ法により肯定応答キーを生成するステップと、 上記肯定応答キーを上記受信側装置から上記送信側装置に伝送するステップと、 上記送信側装置において上記肯定応答キーを確認するステップと、 を有 し、 上記肯定応答キーは、タイムスタンプを有し、 上記肯定応答キーを確認するステップにおいては、上記タイムスタンプと上記肯定応答キーの時間的有効性情報とに基づいて、該肯定応答キーが現在有効であるか否かが判定されることを特徴とする、 データ認証方法。
- 2上記時間的有効性情報は、送信側装置において定義されることを特徴とする請求項1記載のデータ認証方法。
- 3上記肯定応答キーが有効であると判定されると、上記肯定応答キーから第2の乱数データを抽出するステップと 、メ ッセージデータ、第2の乱数データ、及び私用キーに基づいて、キーハッシュ法によりメッセージを生成するステップと、上記メッセージを上記送信側装置から上記受信側装置に伝送するステップと、上記受信側装置において上記メッセージを確認するステップとを有することを特徴とする 請求項1 記載の データ認証 方法。
- 4上記メッセージは、タイムスタンプを有し、上記メッセージを確認するステップにおいては、上記タイムスタンプと 上記メッセージの 時間的有効性情報とに基づいて、該メッセージが現在有効であるか否かを判定することを特徴とする 請求項3 記載の データ認証 方法。
- 5分散型システムにおけるコンピュータ装置に読み込まれるコンピュータプログラムであって、上記コンピュータプログラムは、 請求項1~4のいずれか1項に記載のデータ認証方法を上記コンピュータ装置に実行させる ことを特徴とする 、 コンピュータプログラム。
- 6ネットワークを介する送信側装置と受信側装置との間の データ通信を認証する分散型システムにおいて、 上記送信側装置は、乱数データ、時間的有効性情報、及び私用キーに基づいて、キーハッシュ法によりログインキーを生成し、上記ログインキーを上記送信側装置から上記受信側装置に上記ネットワークを介して伝送し、 上記受信側装置は、キーハッシュダイジェストに基づいて、上記ログインキーの認証有効性及び時間的有効性を確認し、上記ログインキーの認証有効性及び時間的有効性を確認した場合、第2の乱数データと私用キーとに基づいて、キーハッシュ法により肯定応答キーを生成及び上記送信側装置に送信し、 上記送信側装置は、上記肯定応答キーを確認し、 上記肯定応答キーは、タイムスタンプを有し、 上記送信側装置は、上記タイムスタンプと上記肯定応答キーの時間的有効性情報とに基づいて、該肯定応答キーが現在有効であるか否かを判定することを特徴とする、 分散型システム。
- 7上記送信側装置は、上記時間的有効性情報を定義することを特徴とする 請求項6 記載の分散型システム。
- 8上記送信側装置は、上記肯定応答キーが有効であると判定した場合、上記肯定応答キーから第2の乱数データを抽出し 、メ ッセージデータ、第2の乱数データ、及び私用キーに基づいて、キーハッシュ法によりメッセージを生成及び上記受信側装置に送信し、上記受信側装置は、上記メッセージを確認することを特徴とする 請求項6 記載の分散型システム。
- 9上記メッセージは、タイムスタンプを有し、上記受信側装置は、上記タイムスタンプと 上記メッセージの 時間的有効性情報とに基づいて、該メッセージが現在有効であるか否かを判定することを特徴とする 請求項8 記載の分散型システム。
Independent claims9
1 paragraph, as filed
[0001] [Technical field to which the invention belongs] The present invention relates to a data authentication method, a message transmission method, a computer program and a distributed system for authenticating data or a message in data communication from a transmitting side device to a receiving side device. [0002] [Conventional technology] Devices and methods for establishing secure communication between two communication terminal devices, that is, between communication terminals on the data transmitting side (originator) and the data receiving side (destination), have been proposed. For example, there is a method of performing authentication for exchanging a communication partner and a message. In this method, the communication terminal device can confirm whether or not the other party's communication terminal device has a legitimate access right, and can confirm that the received message has not been tampered with unreasonably. [0003] In order to establish secure communication between two communication terminal devices, it is necessary to pay attention to the following four points. First, the communication terminal device on the sending side of the message needs to be authorized to establish communication. Second, the communication terminal device on the receiving side of the message needs to be authorized to receive the message. Thirdly, it is necessary that the message received by the communication terminal device on the receiving side is surely transmitted from the communication terminal on the transmitting side. Fourth, it is necessary to confirm that the message received by the communication terminal device on the receiving side has not been tampered with during communication. [0004] A keyed-hashing message authentication technique is known as a method for establishing such secure communication. In 1996, "Applied Cryptography" by Schneyer and Bruce, published by Edison-Wessley, contains a message authentication code. code: Hereafter, it is called MAC. ) And techniques for implementing one-way cryptographic hashes are described. [0005] Keyed-hashing for message authentication (hereinafter referred to as HMAC) is a method for message authentication using cryptographic hash functions. HMAC can be used with any repetitive cryptographic hash function, such as MD5, SH-1, by combining it with a private (private) shared key. The encryption strength of HMAC is determined by the characteristics of the hash function used. HMAC uses a private key to calculate and confirm the authentication value of a message. [0006] For an example of HMAC, see "Proceeding of Crypto-96, '96 Proceeding of Crypto-96," It is also described in "keying hash functions for message authentication" by Bellare et al. On pages 1 to 15 of "LNCS (lecture notes on computer science) 1109". [0007] [Problems to be Solved by the Invention] In the first communication initial setting process such as the login process in the communication establishment process, a copy of the communication setup information such as the user name and password recorded in the login process is sent to the communication partner, so that the information is invalid. Susceptible to attacks such as copying and replaying. Such information is deciphered using additional knowledge of the other communication terminal and / or a long random number session key or transaction key obtained by intercepting a normal transaction. [0008] Therefore, in view of the above circumstances, the present invention is a more effective data authentication method, message transmission method, computer program, and distributed type that reduces the risk of being attacked by copying, replay, etc., especially in the first communication establishment process. The purpose is to provide a system. [0009] [Means for solving problems] In order to achieve the above object, in the data authentication method according to the present invention, a private key is attached to the data to be authenticated, processing is performed by an encryption hash function, and an encryption hash is performed from the transmitting side device to the receiving side device. In the data authentication method for authenticating data communication by using the key hash method of transmitting data together with the digest of the function, temporal validity information indicating the temporal validity is provided to this data. [0010] This temporal validity information is preferably defined in the transmitting device. [0011] In addition, this data has unique random number data in the period defined by the temporal validity information. [0012] Further, this data may be, for example, a login key and / or a message for communication setup. [0013] Further, in order to achieve the above object, the message transmission method according to the present invention includes a step of generating a login key by a key hash method based on random number data, time validity information, and a private key, and login. It has a step of transmitting the key from the transmitting side device to the receiving side device, and a step of confirming the authentication validity and temporal validity of the login key in the receiving side device based on the key hash digest. [0014] Here, when the authentication validity and temporal validity of the login key are confirmed, the step of generating an acknowledgment key by the key hash method based on the second random number data and the private key, and the acknowledgment key Is transmitted from the receiving device to the transmitting device, and the step of confirming the acknowledgment key in the receiving device is executed. [0015] Further, the acknowledgment key has a time stamp, and in the step of confirming the acknowledgment key, it is determined whether or not the acknowledgment key is currently valid based on the time stamp and the temporal validity information. To do. [0016] Further, this message transmission method includes a step of extracting a second random number data from the acknowledgment key when it is determined that the acknowledgment key is valid, and a message data, a second random number data, and a private key. Based on the above, it has a step of generating a message by the key hash method, a step of transmitting the message from the transmitting side device to the receiving side device, and a step of confirming the message in the receiving side device. [0017] This message has a time stamp, and in the step of confirming the message, it is determined whether or not the message is currently valid based on the time stamp and the time validity information. [0018] Further, in order to achieve the above object, the software program according to the present invention is a computer program read into a computer device in a distributed system, and the computer program attaches a private key to the data to be authenticated. The data communication is authenticated by using the key hash method that performs processing by the encrypted hash function and transmits the data together with the digest of the encrypted hash function from the transmitting side device to the receiving side device. It has temporal effectiveness information indicating the temporal effectiveness of. [0019] Further, in order to achieve the above object, the distributed system according to the present invention attaches a private key to the data to be authenticated, processes it by an encryption hash function, and transfers the data from the transmitting side device to the receiving side device ( In a distributed system that authenticates data communication by using a key hash method that transmits data together with a digest of a (one-way) cryptographic hash function, this data is provided with temporal validity information indicating temporal validity. [0020] Here, the transmitting device may be designed to define temporal (limited) validity information. [0021] [0021] In addition, this data has unique random number data in the period defined by the temporal validity information. [0022] In addition, this data may be a login key and / or a message for communication setup. [0023] Further, in order to achieve the above object, the distributed system according to the present invention is a distributed system that authenticates the transmission of a message, based on random data, temporal validity information, and a private key. Confirm the authentication validity and temporal validity of the login key based on the sender device that generates the login key by the hash method, the network that transmits the login key from the sender device to the receiver device, and the key hash digest. .. [0024] When this receiving device confirms the authentication validity and temporal validity of the login key, it generates an acknowledgment key by the key hash method based on the second random number data and the private key, and sends it to the transmitting device. The transmitting device confirms the acknowledgment key. [0025] Further, the acknowledgment key has a time stamp, and the transmitting device determines whether or not the acknowledgment key is currently valid based on the time stamp and the temporal validity information. [0026] Further, when the transmitting device determines that the acknowledgment key is valid, it extracts the second random number data from the acknowledgment key, and the key is based on the message data, the second random number data, and the private key. A message is generated and sent to the receiving device by the hash method, and the receiving device confirms the message. [0027] This message has a time stamp, and the receiving device determines whether or not the message is currently valid based on the time stamp and the time validity information. [0028] The data authentication method, message transmission method, and distributed system according to the present invention reduce the risk of being attacked by an unjust copy or replay. [0029] BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the data authentication method, the message transmission method, the computer program, and the distributed system according to the present invention will be described in detail with reference to the drawings. [0030] In the time synchronised communication setup (hereinafter referred to as TSCS) based on the present invention, a secure random is used. By using (number generator), almost all setup keys are unique. The setup key is valid only within a predetermined period dynamically defined by the transmitting communication terminal device that initiates communication. The transmitting side communication terminal device and the receiving side communication terminal device confirm each other's access rights. Only when these two communication terminal devices can confirm the access right, the receiving side communication terminal device receives the information from the transmitting side communication terminal device. When the setup key expires, the setup key becomes invalid and cannot be reused. The setup key can be reused within the validity period. This process can be realized without remembering the login key. [0031] The transmitting and receiving communication terminal devices share a single private key of arbitrary length. Private keys are secure with well-known protection protocols such as public key encryption. It can be replaced regularly using protocol). The TSCS communication setup protocol is robust against copy and replay attacks. As mentioned above, TSCS is a method based on keyed-hashing for message authentication (hereinafter referred to as HMAC). HMAC is difficult to decrypt, even if the protected hash functions used, such as SHA-1 and MD-5, are vulnerable, for example, predictable collisions. It is known. [0032] FIG. 1 is a diagram showing an initial connection and information flow of communication between two communication terminal devices based on TSCS by a key hash authentication message. [0033] In step 1, the communication terminal device on the information transmitting side generates a TSCS login key and transmits this TSCS login key to the communication terminal device on the receiving side. As will be described later, the TSCS login key is a (secure) random bit array and ((secure) random bit), unified system time information (unified system). It consists of a time), a temporary validity field, and its authentication key. The longer the random number bit array, the lower the probability that the same random number bit array will be generated. The communication terminal device on the receiving side receives the login key and confirms the authentication key. Since the communication terminal device on the transmitting side and the communication terminal device on the receiving side have a common private key, if the login key is changed, the digest of the login key will be different. In this case, further communication processing is rejected. If the login key is valid here, the communication terminal device on the receiving side confirms the temporal validity described in the temporal validity field. [0034] In stage 2, the receiving communication terminal device generates an acknowledgment key and transmits this acknowledgment key to the transmitting communication terminal device. The acknowledgment key is composed of a random number bit array different from the random number bit array included in the authentication key from the communication terminal device on the receiving side, and integrated system time information on the receiving side. [0035] In step 3, the communication terminal device on the transmitting side confirms the acknowledgment key, that is, the digest and the temporal validity, and merges the message data to be transmitted into the random number bit array of the acknowledgment key. The transmitting side communication terminal device signs this data, that is, data consisting of a message and a random number field, and transmits the data to the receiving side communication terminal device. [0036] In step 4, the receiving communication terminal device confirms the identity of the message digest and the random number bit field from the message and the previously generated random number bit array. Here, if the digest of the message is valid and it is confirmed that the random number bit array has the same identity, this message has not been tampered with and the previous login key and acknowledgment key exchange was performed. It is the result of. In this case, the communication terminal device on the receiving side transmits an acknowledgment signal to the communication terminal device on the transmitting side. [0037] FIG. 2 is a diagram showing a specific example of the TSCS login key and the acknowledgment key. The login key is generated and signed by the transmitting communication terminal device. The acknowledgment key is signed and returned by the receiving communication terminal device. Note that HMAC, which has a full digest length, does not necessarily require the transmission of a signature. For login and acknowledgment keys, compressing the digest to limit its data length is important for security and key length. [0038] FIG. 3 is a diagram showing the structure of the TSCS login key. In this example, the HMAC key digest is compressed to shorten the key length and prevent the private key K from being decrypted if the signed message is short. In this embodiment, the length of the signed message is 265 bits. If the message length is short, compression to an 80-bit digest length is effective. [0039] As described above, the initial connection process between the two communication terminal devices consists of four stages. Hereinafter, the four steps based on the present invention will be described in more detail. [0040] Step 1: Login of the communication terminal device on the sending side a) Generate a TSCS login key.<u style="single"></u>b) Generate a protected random number bit array.<u style="single"></u>c) Attach the unified time (UT) field.<u style="single"></u>d) Attach a temporal effectiveness field.<u style="single"></u>e) Generate HMAC using private key K.<u style="single"></u>f) Attach HMAC (or a subset thereof) to your login key. g) Send the login key to the communication terminal device on the receiving side. [0041] Stage 2: Acknowledgment on the receiving side a) [Option 1] Search the key table for the same key as the random number bit field of the current login key.<u style="single"></u>b) [Option 1] If a duplicated key is detected in the key table, disconnect and end the process. c) [Option 1] Save the random number bit array of the login key in the key table until the key disappears. d) Check the authentication validity and temporal validity of the login key.<u style="single"></u>e) Check the login key signature (digest)<u style="single">。</u><u style="single"></u>f) Calculate your own HMAC using your private key K.<u style="single"></u>g) Compare your HMAC with a digest of your login key.<u style="single"></u>h) Check the temporal validity of the login key.<u style="single"></u>i) Calculate the difference between the integrated time information of the login key and the current time on the receiving side.<u style="single"></u>j) Make sure that the time difference (absolute value) is shorter than the valid period of the login key. k) Generate an acknowledgment key.<u style="single"></u>l) Generate a protected random number bit array (session key)<u style="single">。</u><u style="single"></u>m) Save the session key<u style="single">。</u><u style="single"></u>n) Attach the integrated time (UT) field<u style="single">。</u><u style="single"></u>o) Generate an HMAC using private key K.<u style="single"></u>p) Attach HMAC (or a subset thereof) to the acknowledgment key.<u style="single">q) Send an acknowledgment key to the communication terminal device on the transmitting side.</u>[0042] Stage 3<u style="single">:</u>Send Messege a) Confirm the authentication validity and temporal validity of the acknowledgment key.<u style="single"></u>b) Check the signature (digest) of the acknowledgment key<u style="single">。</u><u style="single"></u>c) Calculate your own HMAC using your private key K.<u style="single"></u>d) Compare your HMAC with a digest of the acknowledgment key.<u style="single"></u>e) Check the temporal validity of the acknowledgment key.<u style="single"></u>f) Calculate the difference between the acknowledgment key integrated time information and the sender's current time.<u style="single"> g</u>) Make sure that the time difference (absolute value) is shorter than the acknowledgment key validity period. h) Extract the random bit field from the acknowledgment key. i) Attach or merge message data to a random number bit field (session key). j) [Option 2] Attach the integrated time information of the sender to the message. k) Sign the message data and session key.<u style="single">That is,</u>Calculate the HMAC of the message data and session key using the private key K. The integration time may also be signed. l) Attach to HMAC (or a subset thereof) message data and session key. m) Send a message. That is, message data, session key, HMAC<u style="single">Vedanā</u>Send to the trust side. [0043] Stage 4: Message confirmation a) Check the authentication validity of the message and (temporal validity as an optional item).<u style="single"></u>b) Compare the session key of the message with the previously saved session key.<u style="single"></u>c) Check the signature (digest) of the message<u style="single">。</u><u style="single"></u>d) Calculate your own HMAC using your private key K.<u style="single"></u>e) Compare your HMAC with the message digest.<u style="single"></u>f) [Option 2] Check the temporal validity of the message.<u style="single"></u>g) [Option 2] Compare the message integration time with the current time on the receiving side.<u style="single"></u>h) [Option 2] Make sure that the time difference (absolute value) is shorter than the validity period of the message. i) Return an acknowledgment signal to the sender. [0044] Option 1 is designed to protect against so-called replay attacks with multiple TSCS login keys that may be received even within the validity period defined in the attached lifetime field. The validity period can be defined by the user in the range of several nanoseconds to several minutes. Especially in the Internet environment, the validity period is set longer, and in the directly connected network, the validity period is set shorter. [0045] Option 2 is the process that is performed when the message itself also defines a time period for temporal validity. [0046] As described above, the present invention realizes an authentication process for message transmission in a distributed messaging communication environment. Authentication of time-synchronized messages and communications applies to message communications between two communication terminal devices. Furthermore, by slightly extending this method, TSCS can also be applied to one-to-N communication processing such as broadcast communication or broadcasting. The present invention relates to message-oriented communication processing. Logically, message-oriented means that communication is established in the first processing stage, then the message is transmitted, and in the third processing stage, an acknowledgment is returned as an optional item from the receiving communication terminal device. means. Message-oriented communication is unsuitable for processes that require continuous one-way or two-way data transmission, such as real-time audio transmission and video transmission. [0047] The method for establishing a communication between two communication terminal devices and realizing a secure authentication method for message transmission has been described above. By TSCS using key hash message authentication, it is possible to authenticate the communication terminal device to be the communication partner and authenticate the transmission information. Also, both communicating terminal devices share only a single private key that is periodically changed between the two communication terminal devices by a well-known public key encryption method for key transmission. In addition, by setting a time-effectiveness limit of several nanoseconds to several days, it is possible to improve the security of communication and prevent copy attacks or replay attacks. Transmission of message data that does not have a legitimate title due to a replay attack or the like is almost detected. While the protected random key is stored for its lifetime, replay attacks during the communication setup phase that do not compromise message integrity are nearly impossible. After the period defined by the transmitting terminal device that initiates communication, the previously exchanged session key cannot be reused. The property of this key cannot be recognized unless the session key is saved. According to this method, it is possible to set a temporal validity period for the transmission information. [0048] [Effect of the invention] As described above, in the data authentication method according to the present invention, a private key is attached to the data to be authenticated, processing is performed by an encryption hash function, and a digest of the encryption hash function is performed from the transmitting side device to the receiving side device. A key hash method for transmitting data is used, and temporal effectiveness information indicating temporal effectiveness is provided in the data. This makes it possible to reduce the risk of being attacked by copying, replaying, etc. when sending and receiving data such as messages. [0049] Further, the message transmission method according to the present invention generates a login key by a key hash method based on random number data, temporal validity information, and a private key, and transmits the login key from the transmitting side device to the receiving side device. Then, in the receiving device, the authentication validity and temporal validity of the login key are confirmed based on the key hash digest. This makes it possible to reduce the risk of being attacked by copying, replaying, etc. when sending and receiving data such as messages. [0050] Further, the software program according to the present invention attaches a private key to the data to be authenticated, performs processing by the cryptographic hash function, and transmits the data from the transmitting side device to the receiving side device together with the digest of the cryptographic hash function. In addition to using the key hash method, temporal validity information indicating the temporal validity is provided in the data. This makes it possible to reduce the risk of being attacked by copying, replaying, etc. when sending and receiving data such as messages. [0051] Further, in the distributed system according to the present invention, a private key is attached to the data to be authenticated, processing is performed by the encryption hash function, and the data is transmitted from the transmitting side device to the receiving side device together with the digest of the encryption hash function. In addition to using the key hash method, the data is provided with temporal validity information indicating the temporal validity. This makes it possible to reduce the risk of being attacked by copying, replaying, etc. when sending and receiving data such as messages. [0052] Further, the distributed system according to the present invention is a transmission that generates a login key by a key hash method based on random data, temporal validity information, and a private key in a distributed system that authenticates the transmission of a message. Based on the side device, the network that transmits the login key from the sending device to the receiving device, and the key hash digest, the authentication validity and temporal validity of the login key are confirmed. This makes it possible to reduce the risk of being attacked by copying, replaying, etc. when sending and receiving data such as messages. [Simple explanation of drawings] FIG. 1 is a diagram showing an initial connection and information flow of communication between two communication terminal devices based on TSCS by a key hash authentication message. FIG. 2 is a diagram showing the contents of a TSCS login key and an acknowledgment key. FIG. 3 is a diagram showing a data structure of a TSCS login key.
3 sheets
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Every citation, both waysCites: the store holds 3 of 4
| Document | Relation | Office |
|---|---|---|
| US05757920A | Cites | United States of America |
| JP11119649A | Cites | Japan |
| WO99057846A1 | Cites | World Intellectual Property Organization (WIPO) |
| M. Bellare, R. Canetti, and H. Krawczyk,"Keying Hash Functions for Message Authentication",Advances in Cryptology -- CRYPTO '96,1996年,LNCS vol. 1109,pp. 1--15 | Non-patent | – |
9 members in 4 offices
Priority claims5
| Document | Office | Kind | Date |
|---|---|---|---|
| 99124150 | European Patent Office (EPO) | A | |
| 99124150 | European Patent Office (EPO) | A | |
| 991241506 | European Patent Office (EPO) | – | |
| 199999124150 | – | – | – |
| EP19990124150 | – | – | – |
Members9
| Document | Office | Kind | |
|---|---|---|---|
| EP1104960A1 | European Patent Office (EPO) | A1 | |
| US2001002929A1 | United States of America | A1 | |
| JP2001202014A | Japan | A | |
| US7213149B2 | United States of America | B2 | |
| US2007162757A1 | United States of America | A1 | |
| EP1104960B1 | European Patent Office (EPO) | B1 | |
| DE69941335D1 | Germany | D1 | |
| US7949875B2 | United States of America | B2 | |
| JP4689815B2This record | Japan | B2 |
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Numbers
- Publication
- 4689815
- Publication, DOCDB
- 4689815
- Publication, EPODOC
- JP4689815B
- Application
- 365712
- Application, DOCDB
- 2000365712
- Application, EPODOC
- JP20000365712
Titles2
- Japanese
- データ認証方法、メッセージ伝送方法及び分散型システム
- English
- Data authentication method, message transmission method and distributed system
Classification
- CPC, 5
- H04L63/0442
- H04L9/3242
- H04L9/3297
- H04L63/061
- H04L63/126
- IPC, 4
- G09C1 00
- H04L9 32
- H04L9 08
- H04L29 06
