RU2637486C2 - System for monitoring integrity of continuously maintained data records logs - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: system for monitoring the integrity of continuously maintained data records logs, executed as an administration server containing the first entry of data records, the first hash code generation unit, the first foreign key storage unit, the second foreign key storage unit, and the second hash code generation unit. In addition, foreign key switching unit, internal key switching unit, k-2 foreign key storage units, m-2 hash code generation units, m-1 data entry inputs, m-1 outputs of the protected data record system, m concatenation units with memory, foreign key distribution function key storage unit, internal key distribution function key storage unit.

EFFECT: ensuring the necessary level of protection of data records in the file based on specifying the corresponding parameters of the oneshot method, the nesting degree in the data block, and the number of foreign keys used.

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Description

Technical field

The invention relates to systems and methods for ensuring information security in automated systems (AS), and in particular to systems and methods for monitoring the integrity of data processed in AS.

State of the art

To ensure the security of information in the AU, the integrity of various files (operating system boot files, antivirus program files, etc.) is important. In addition, there are log files of continuously maintained data records (for example, security audit log files), the integrity of which must be monitored. At the same time, these logs can be changed accidentally or intentionally, the log can be replaced, or log entries can be accidentally or intentionally overwritten. Known technical solutions for monitoring data integrity:

1. Patent US 20030192033, Validating computer program installation, 2002, [Electronic resource] - https://books.google.com.tr/patents/US 20030192033.

2. The software package "Shield System Manager subsystem integrity control (Integrity Control System), [Electronic resource] - http://lissiru.narod.ru/products/index.html.

3. The hardware-software complex of trusted download "Blockhost-MDZ [Electronic resource] - https://gaz-is.ru/poddergka/download/finish/6/8.html.

In these solutions, a hash function is used to control the integrity of information (a function that maps strings of bits of the original data to strings of bits of a fixed length - a hash code).

The disadvantage of such solutions is the low level of protection of data records from attacks by authorized users (insiders). When maintaining consecutive records of data in a file (records in an electronic medical history, a security audit event log), a user (or one of the administrators), having his own key (when using key hash functions), has the ability to modify (fake) his records recorded in file earlier. That is, these solutions do not take into account internal threats to data security from legal users (insiders).

A known system for monitoring the integrity of data records based on the method of "write once" (Atsushi Harada, Masakatsu Nishigaki, Masakazu Soga, Akio Takubo, Itsukazu Nakamura. A Write-Once Data Management System, ICITA 2002. - Shizuoka University, Japan, 2002, [Electronic resource] - http://www.icita.org/previous/icita2002/ICITA2002/kptdata/116-21/index.htm), which uses various combinations of electronic user signatures to protect (integrity control) records from authorized users.

The disadvantage of this solution is the lack of functionality to establish additional parameters for entering key data of various users and the procedure for their application (secret for the users themselves or for different groups of users, the composition of which is not known to the users themselves), which allows providing an appropriate level of security for data records in a file.

The closest in technical essence to the proposed system (prototype) is the hash-based message authentication system, the essence of which is the use of a cryptographic hash function in combination with one secret key and NMAC with two secret keys (M. Bellare, R. Canetti and N. Krawczyk, Keying Hash Functions for Message Authentication, Advances in Cryptology Proceedings of CRYPTO 1996, pp. 1-15, Springer-Verlag, [Electronic resource] - http://dblp.uni-trier.de/ db / conf / crypto / crypto96, [Electronic resource] - http://daily.sec.ru/2012/07/16/print-Algoritmi-auntentifikatsii-soobsheniy-HMAC-i-NMAC.html).

The NMAC message authentication system consists of: an input for a message connected to the first input of the first hash code generation unit, a storage unit of the first secret (external) key, the output of which is connected to the second input of the first hash code generation unit, the output of which is connected to the first input a second hash code generating unit, a second secret (external) key storage unit, the output of which is connected to the second input of the second hash code generating unit, the output of which is connected to the output of the message authenticity code.

, где

- символ конкатенации, hash - функция вычислений в блоке формирования хэш-кода. Сообщение с кодом аутентичности (М, N) по каналу передачи сообщения, расположенного в недоверительной среде, поступает получателю. Доверительная сторона (получатель сообщения) осуществляет проверку соответствия полученного кода аутентичности Н* для контроля целостности и аутентификации сообщения М*.Monitoring the integrity of the message is that the sender of the message M using two secret (external) keys k ₁ and k ₂ calculates the authenticity code of the message according to the rule:

where

is a concatenation symbol, hash is a calculation function in the hash code generation unit. A message with an authenticity code (M, N) is sent to the recipient via a message channel located in an untrusted environment. The trusted party (recipient of the message) checks the compliance of the received authenticity code H * to control the integrity and authentication of the message M *.

The disadvantage of the prototype is the low level of data protection from attacks by authorized users (insiders) (requires two parties trusting each other, confidentiality of secret keys).

A feature of the logs of continuously maintained data records is the dynamism and continuity of data writing to a file. The file is constantly updated by adding new entries. Due to the circumstances, it becomes clear that a new system for detecting changes in log files is needed, which provides protection (integrity control) of data from authorized users (internal threats to data security).

Disclosure of invention

The present invention is intended to solve the problem of detecting attacks on speakers by authorized users (insiders).

The technical result consists in the fact that the system allows to provide the necessary level of protection for data records in a file based on setting the corresponding parameters of the “write once” method: the degree of nesting of records in the data block, the number of foreign keys used.

To control data integrity in the AS, both keyless hash functions (prototype) and key hash functions that were used in the invention to provide the required level of data security can be used. By foreign keys in the invention we mean cryptographic keys of a hash function.

The specified technical result is achieved in that in the known NMAC message authentication system, including: an input for data records that is connected to the first input of the first hash code generation unit, a storage unit of the first foreign key, a storage unit of the second foreign key, and a second hash generation unit the code, the output of which is connected to the output of the system of protected data records, is additionally introduced: a block for switching foreign keys, a block for switching internal keys, which hereinafter refers to the values obtained in as a result of concatenation, k-2 blocks of storage of foreign keys, m-2 blocks of generating a hash code, m-1 inputs of data records, m-1 outputs of a system of protected data records, m blocks of concatenation with memory, key storage block of a foreign key distribution function, a key storage unit for the internal key distribution function, k k foreign key storage units are connected to the first inputs of the foreign key switching unit, a key storage unit of the foreign key distribution function is connected to the second input of the foreign key switching unit, outputs are cat They are connected to the second inputs of the hash code generation blocks, m-1 inputs of data records are connected to the first inputs of m-1 hash code generation blocks and m inputs of data records are connected to the second inputs of m memory concatenation blocks, m-1 outputs of the generation blocks hash codes are m-1 outputs of the secure data recording system and m outputs of the secure data recording system are connected to the first inputs of m concatenation units with memory, the outputs of which are connected to the first inputs of the internal key switching unit, the outputs of which are connected a third input of blocks forming a hash code, second input key internal switching unit connected to the output of the storage unit key internal key distribution function.

These distinctive features in comparison with the prototype allow us to conclude that the claimed technical solution meets the criterion of "novelty."

The invention consists in the following. If the prototype is used to control the integrity of the logs of continuously maintained data records, an authorized user (the owner of the keys k ₁ and k ₂ ) can hide the fact of an attack on the speakers by changing the entries in the file. Distinctive features in comparison with the prototype are the use of k foreign keys and m internal keys, a foreign key switching unit, an internal key switching unit, m concatenation blocks with memory, which ensures the required level of data protection (from an internal intruder), and prevents users from trying to hide traces previously implemented destructive effects on the magazine, as well as detect facts of an attack on the speakers.

To describe the essence of the invention, we introduce the following notation:

- множество двоичных векторов произвольной конечной длины (множество непрерывно поступающих записей данных в файл);

- a set of binary vectors of arbitrary finite length (a set of continuously incoming data records in a file);

- двоичный вектор произвольной конечной длины

, представляющий произвольную запись и соответствующий моменту времени t_i+k;

is a binary vector of arbitrary finite length

representing an arbitrary record and corresponding to time t _{i + k} ;

- бесключевая хэш-функция, отображающая двоичный вектор

произвольной конечной длины

в сигнатуру

(двоичный вектор длины

бит);

- keyless hash function displaying a binary vector

arbitrary finite length

to signature

(binary length vector

bit);

d _j - cryptographic (foreign) key;

- сигнатура ключевой хэш-функции под записью

;

- signature of the key hash function under the entry

;

- получение сигнатуры ключевой хэш-функции;

- Obtaining the signature of the key hash function;

- операция конкатенации двоичных векторов.

- operation of concatenation of binary vectors.

To ensure data integrity with one foreign key d _{1, we} use the result of concatenation of two binary vectors as an argument to the hash function:

;

;

- внутренний ключ.Where

- internal key.

для элемента из множества

:Then

for an element from the set

:

,

,

Records in the data block are updated only by adding new records, and the data structure is required to preserve the order of the records, therefore, to obtain dependent protected data blocks, the binary vector concatenation operation is applicable.

для элемента из множества

:Then

for an element from the set

:

.

.

We use the following expression to determine the parameters:

,

,

where the coefficients: (s ₁ , s ₂ , ..., s _h ) - determine the nesting in the data block, d _j - the number of foreign keys used.

(множество всех криптографических ключей пользователей).Foreign keys d ₁ and d ₂ are used randomly (according to a certain algorithm) from the set

(the set of all cryptographic keys of users).

To hide the fact of an attack (data modification), an attacker needs to conspire with all key owners and know the data integrity algorithm for this AS, which can be dynamically changing (changing the parameters of the "write once" method).

Description of drawings

The drawing shows: FIG. 1 is a diagram of a system for monitoring the integrity of logs of continuously maintained data records.

In FIG. 1 shows a system for monitoring the integrity of the logs of continuously maintained data records, made in the form of an administration server, which contains: blocks 1.1-1.k of storage of foreign keys, block 2 of the key storage function of the distribution of foreign keys, block 3 of switching foreign keys, blocks 4.1-4. m hash code generation, key storage unit 5 of the internal key distribution function, internal key switching unit 6, inputs 7.1-7.m of data records, outputs 8.1-8.m of a secure data record system, memory concatenation blocks 9.1-9.m , and blocks 1.1-1.k kept The foreign key connections are connected to the first inputs of the foreign key switching unit 3, the key storage unit 2 of the foreign key distribution function is connected to the second input of the foreign key switching unit 3, the outputs of which are connected to the second inputs of the hash code generation blocks 4.1-4.m, inputs 7.1 -7.m of data records are connected to the first inputs of hash codes generation blocks 4.1-4.m and to the second inputs of concatenation blocks 9.1-9.m with memory, the outputs of hash codes generation blocks 4.1-4.m are outputs 8.1-8 .m secure data record systems and are connected first and the inputs of memory concatenation blocks 9.1-9.m, the outputs of which are connected to the first inputs of the internal key switching unit 6, the outputs of which are connected to the third inputs of the hash codes generation blocks 4.1-4.m, the second input of the internal key switching unit 6 the output of the key storage unit 5 of the internal key distribution function.

Description of the claimed invention

The system contains 7.1-7.m inputs that continuously receive data records, the sources of which can be: file servers, user workstations, warning and detection systems for computer attacks, access control systems, anti-virus programs, etc.

Blocks 4.1-4.m are functionally independent blocks made in the form of sections of memory of a computing device and designed to calculate the signature of the hash function.

The outputs 8.1-8.m of the system of protected data records are recorded in a log of continuously maintained data records made in the form of a table or database in which causal relationships between records are determined (chronological sequence, etc.).

Blocks 1.1-1.k are identical to the key storage units presented in the prototype and represent data storage devices in readable computer form (hard drives, flash cards, optical disks, RAM, etc.). Storage devices can be located on user workstations distributed over the network and use a network connection to communicate with them.

Blocks 2 and 5 of the key storage of the distribution function (internal and foreign keys) represent data storage devices that can be located both in distributed workstations and in the workplace of the system administrator. The key is presented in the form of a binary matrix, the rows of which correspond to the internal (foreign) keys, and the columns are the numbers of the outputs of the switching blocks (3, 6).

Block 3 is designed for switching foreign keys from blocks 1.1-1.k in accordance with the key distribution function from block 2.

Block 6 is intended for switching internal keys obtained from blocks 9.1-9.m, in accordance with the key, with the distribution function from block 5.

Memory concatenation blocks 9.1-9.m are designed to receive internal keys and represent data storage devices in computer-readable form that can be placed on users' workstations distributed over the network and use a network connection to communicate with them.

The system operates as follows.

In the initial state, foreign keys are written in blocks 1.1-1.k (hash function cryptographic keys: d ₁ , d ₂ , ..., d _k ). The keys are recorded in blocks 2 and 5, according to which in blocks 3 and 6 a distribution function of foreign and internal keys is implemented for feeding the hash code to blocks 4.1-4.m.

,

,

, …,

, которые поступают на первые входы блоков 4.1-4.m формирования хэш-кода и вторые входы блоков 9.1-9.m конкатенации с памятью.Step 1: simultaneously the data records are received at the inputs 7.1-7.m:

,

,

, ...,

which go to the first inputs of hash code blocks 4.1-4.m and the second inputs of concatenation blocks 9.1-9.m with memory.

,

, …,

, полученные в предыдущем цикле. В блоках 4.1-4.m формирования хэш-кода вычисляется сигнатура хэш-функции:

.Step 2: foreign keys arrive at the second inputs of the blocks 4.1-4.m of the hash code generation from block 3: d ₁ , d ₂ , ..., d _k , the third inputs of the hash code generation blocks 4.1-4.m from block 6 internal keys arrive:

,

, ...,

obtained in the previous cycle. In the blocks 4.1-4.m of the formation of the hash code, the signature of the hash function is calculated:

.

,

, …,

поступают на выходы 8.1-8.m системы защищенные записи данных и первые входы блоков 9.1-9.m конкатенации с памятью. В блоках 9.1-9.m конкатенации с памятью вычисляются внутренние ключи

, значения которых заполняют ячейки памяти.Step 3: from the outputs of blocks 4.1-4.m generating a hash code protected records

,

, ...,

Protected data records and the first inputs of concatenation blocks 9.1-9.m with memory are sent to outputs 8.1-8.m of the system. In blocks 9.1-9.m concatenation with memory internal keys are calculated

whose values fill the memory cells.

.Next, the system operation cycle is repeated from the 1st step for all m-blocks: M _{t + 1} , M _{t + 2} , ...,

.

Thus, the block 3 for switching foreign keys, block 6 for switching internal keys, k-2 blocks 1.3-1.k for storing foreign keys, m-2 blocks 4.3-4.m for generating a hash code, m-1 inputs 7.2 -7.m data records, m-1 outputs 8.2-8.m of a protected data recording system, m concatenation blocks 9.1-9.m with memory, key storage unit 2 of the foreign key distribution function, key storage unit 5 of the internal key distribution function featured "significant differences" and provide a positive effect.

It should be noted that the information provided in the description are only examples that do not limit the scope of the present invention described by the claims. There are other embodiments of the present invention consistent with the spirit and scope of the present invention.

Claims (1)

An integrity monitoring system for logs of continuously maintained data records made in the form of an administration server, containing the first input of data records, connections to the first input of the first hash code generation unit, the storage unit of the first foreign key, the storage unit of the second foreign key, the second hash code generation unit the output of which is the second output of the secure data recording system, characterized in that it is additionally introduced: a foreign key switching unit, an internal key switching unit, k-2 storage units foreign keys, m-2 hash code generation blocks, m-1 entries of data records, m-1 outputs of a secure data recording system, m concatenation blocks with memory, key storage unit of the foreign key distribution function, key storage unit of the internal key distribution function, moreover, k foreign key storage units are connected to the first inputs of the foreign key switching unit, the key storage unit of the foreign key distribution function is connected to the second input of the foreign key switching unit, the outputs of which are connected to the second inputs of the blocks hash code generation, m-1 inputs of data records are connected to the first inputs of m-1 hash code generation blocks and m inputs of data records are connected to the second inputs of m concatenation blocks with memory, m-1 outputs of hash code generation blocks are m- 1 outputs of the system of secure data records and m outputs of the system of secure data records are connected to the first inputs of m concatenation blocks with memory, the outputs of which are connected to the first inputs of the switching block of internal keys, the outputs of which are connected to the third inputs of the generating blocks x br codes, the second input key internal switching unit connected to the output of the storage unit key internal key distribution function.

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