CN107241451B - Method, device and system for tampering intervention based on content distribution network - Google Patents

Abstract

The invention discloses a tampering intervention method, device and system based on a content distribution network. The method includes: a CDN edge node receives a request message from a user terminal, and the request message requests a request for a static file; And initiate a back-to-origin request; receive a response message and send it to the user terminal; determine whether the static file in the response message has been tampered with; if it has not been tampered with, cache the static file; if it has been tampered with, it will not cache the static file. When the message of the static file is sent, the back-to-origin request is re-initiated. If the origin site returns a normal response and there is no tampering between the origin site and the CDN edge node, the static file of the normal response is cached to achieve tampering recovery. In the present invention, the CDN edge node can timely find out that the file has been tampered with by judging, and does not cache the tampered file, and the user can perform the tampering recovery next time when the user requests the file, which shortens the tampering recovery time.

Description

Method, device and system for tampering intervention based on content distribution network

technical field

The invention relates to the technical field of data anti-tampering and tampering recovery, in particular to a tampering intervention method, device and system based on a content distribution network.

Background technique

The basic idea of content tamper-proof technology based on Content Delivery Network (CDN) is that the response header in the user request CDN network does not carry Cache-Control: no-cache or no-store or private or max-age= 0 files, that is, static files cached on CDN edge nodes (hereinafter referred to as static files for this type of files), if the static files are maliciously inserted into code fragments or file fragments, the user will respond to unexpected content, such as advertising pop-ups. Wait.

The steps of the current content tamper-resistant recovery solution are as follows:

(1) When a user requests a newly released static file or an expired static file from the source site, the CDN edge node needs to make a back-to-source request;

(2) The source station monitoring module of the CDN edge node selects which source station to return, and the CDN edge node initiates a back-to-source request to the source station;

(3) The source station responds normally;

(4) The CDN edge node will return the response to the user and cache the corresponding file, regardless of whether the file has been maliciously tampered with.

(5) If the file is maliciously tampered with, before the file expires, if a user requests the file, the CDN edge node directly sends the cached file to the user, that is, the user receives the tampered file. . If the CDN edge node determines that the file is expired and a user requests the file, the CDN edge node initiates a back-to-source request, and there is no malicious tampering between the source station and the CDN edge node. At this time, the tampering is restored and the user responds normally, that is, the user Able to receive files that have not been maliciously tampered with.

The above content tamper-proof recovery scheme has the following drawbacks: regardless of whether the requested static file is maliciously tampered with, the CDN edge node caches the static file. If malicious tampering occurs, the malicious tampering will be recovered only when the cache expires and the origin site gives a normal response, and the malicious tampering will not be reset. Rapid recovery cannot be achieved during the entire recovery process. During the period of expiration, all requests for the file return maliciously tampered files, which prolongs the time of the failure and aggravates the impact of the failure. For example, when visiting a commonly used webpage or shopping mall, it is found that the advertisement pop-up window always exists, which affects the user experience; if the cache time of the empty response file is 1 day, it will be possible to return to normal after at least 1 day after the cache expires and a user requests the file.

SUMMARY OF THE INVENTION

In order to solve the problem in the prior art that tampering recovery needs to wait for file expiration, which affects user experience, embodiments of the present invention provide a content distribution network-based tampering intervention method, device, and system.

According to an aspect of the embodiments of the present invention, a method for tampering intervention based on a content distribution network is provided, including:

The CDN edge node of the content distribution network receives a request message from the user terminal, wherein the request message requests a static file;

The CDN edge node determines the source station of the back-to-source, and initiates a back-to-source request;

The CDN edge node receives the response message of the source station, and sends the response message to the user terminal;

The CDN edge node determines whether the static file in the response message has been tampered with;

If it has not been tampered with, cache the static file;

If it is tampered with, the static file will not be cached. When receiving a message requesting the static file again, the CDN edge node will re-initiate a back-to-origin request. If the origin site returns a normal response and the origin No tampering occurs between the station and the CDN edge node, and the CDN edge node caches the static file of the normal response to realize tampering recovery.

Further, the CDN edge node determines whether the static file in the response message has been tampered with, including:

The CDN edge node obtains at least two first feature values from corresponding at least two response messages respectively;

The CDN edge node judges whether the at least two first feature values are consistent;

If it is consistent, it is determined that the static file has not been tampered with;

If not, it is determined that the static file has been tampered with.

Further, the method further includes: when the CDN edge node judges whether the at least two first characteristic values are consistent, first judge whether it is the first time that a request message for requesting the static file is received.

Further, the CDN edge node determines whether the static file in the response message has been tampered with, including:

The CDN edge node extracts the second feature value carried in the response message, wherein the second feature value uniquely identifies the static file;

The CDN edge node uses the calculation method negotiated with the source station to calculate and obtain the third characteristic value according to the response message;

The CDN edge node determines whether the second eigenvalue is consistent with the third eigenvalue;

If it is consistent, it is determined that the static file has not been tampered with;

If not, it is determined that the static file has been tampered with.

Further, the CDN edge node determines whether the static file in the response message has been tampered with, including:

The negotiated calculation method is a calculation method negotiated with the CDN system in advance by the source station.

Further, if there are multiple CDN nodes between the source station and the user terminal, the CDN edge node sending the response message to the user terminal includes:

The CDN edge node processes the response message by using a preset private protocol among the multiple CDN nodes;

The CDN edge node transmits the processed response message through the multiple CDN nodes;

When the CDN edge node on the user terminal side receives the processed response message, it restores the processed response message by using the preset private protocol, and sends the restored response message to the user terminal.

According to another aspect of the embodiments of the present invention, there is provided a content distribution network-based tampering intervention device, which is applied to a CDN edge node of a content distribution network, and the device includes:

a receiving unit, configured to receive a request message from a user terminal and a response message from the source station;

The back-to-source unit is used to determine the back-to-source origin station and initiate a back-to-source request;

a first sending unit, configured to send the response message to the user terminal;

a judging unit for judging whether the static file in the response message has been tampered with;

a cache unit, configured to cache the static file without being tampered with;

A processing unit, configured to not cache the static file in the case of being tampered with, and re-initiate the back-to-origin request when the message requesting the static file is received again, if the origin site returns a normal response And no tampering occurs between the source station and the CDN edge node, and the static file of the normal response is cached to realize tampering recovery.

Further, applied to a CDN edge node of a content distribution network, the device includes:

The receiving unit includes a first receiving unit and a second receiving unit, wherein the first receiving unit is configured to receive a request message from a user terminal; the second receiving unit is configured to receive a response message from the source station.

Further, the judging unit includes:

a first judging module for judging whether it is the first time that a request message requesting the static file is received;

an obtaining module, configured to obtain at least two first characteristic values from the response message;

a second judgment module, configured to judge whether the at least two first characteristic values are consistent;

A first determining module, configured to determine that the static file has not been tampered with in the case of consistency; and determine that the static file has been tampered with in the case of inconsistency.

Further, the judging unit is configured to judge whether it is the first time to receive a request message requesting the static file; obtain at least two first characteristic values from the response message and judge whether the at least two first characteristic values are Consistent; and for determining that the static file has not been tampered with in the case of consistency, and determining that the static file has been tampered with in the case of inconsistency.

Further, the judging unit includes:

an extraction module, configured to extract the second characteristic value carried in the response message, wherein the second characteristic value uniquely identifies the static file;

a calculation module, configured to obtain a third eigenvalue according to the response message by using a calculation method negotiated with the source station, and the calculation method is a calculation method negotiated with the CDN system in advance by the source station;

a third judgment module, configured to judge whether the second characteristic value is consistent with the third characteristic value;

The second determining module is configured to determine that the static file has not been tampered with in the case of consistency; and determine that the static file has been tampered with in the case of inconsistency.

Further, the judging unit is used to extract the second characteristic value carried in the response message, wherein the second characteristic value uniquely identifies the static file; for using the calculation method negotiated with the source station, The third characteristic value is calculated and obtained according to the response message, and the calculation method is a calculation method negotiated by the source station with the CDN system in advance; it is used to judge whether the second characteristic value is consistent with the third characteristic value ; and for determining that the static file has not been tampered with in the case of consistency, and determining that the static file has been tampered with in the case of inconsistency.

Further, the first sending unit includes:

A processing module, configured to process the response message by using a preset private protocol between the multiple CDN nodes when there are multiple CDN nodes between the source station and the user terminal, and after processing The response message cannot be recognized by other devices;

a transmission module, configured to transmit the processed response message through the multiple CDN nodes;

The restoration module is configured to use the preset private protocol to restore the processed response message when the CDN edge node on the user terminal side receives the processed response message, and send the restored response message to the user terminal.

According to yet another aspect of the embodiments of the present invention, a content distribution network-based tampering intervention system is provided, including: a user terminal, a content distribution network CDN edge node, and a source station, wherein,

The user terminal is configured to send a request message, wherein the request message requests a static file;

The CDN edge node includes the content distribution network-based tampering intervention device;

The origin site includes:

a third receiving unit, configured to receive a back-to-source request sent by the CDN edge node;

The second sending unit is configured to send a response message to the CDN edge node.

Further, the source site also includes:

A computing unit, configured to obtain a characteristic value uniquely identifying the static file by using a calculation method negotiated with the CDN edge node in advance, and place the characteristic value in the response message.

The technical solution of the embodiment of the present invention determines whether the file has been maliciously tampered with by the CDN edge node. If there is no malicious tampering, the file is normally cached. Re-request, when the source station responds normally and there is no tampering between the source station and the CDN edge node, then the tampering is restored. CDN edge nodes can detect maliciously tampered files in time by judging, and do not cache maliciously tampered files; there is no need to wait for the cache to expire before maliciously tampered recovery, as long as the user requests the file next time, maliciously tampered recovery can be performed, shortening the time To save the time for tampering and recovery, abnormal data can be recovered in time to ensure user experience. In addition, data that cannot be identified by other devices is transmitted between multiple CDN nodes through a preset private protocol, ensuring that the content transmitted between CDN nodes will not be maliciously tampered with, and at the same time, it can effectively modify the congestion policy in time for network conditions. Improve transmission speed and stability to ensure user experience.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

1 is a flowchart of a method for tampering intervention based on a content distribution network provided by an embodiment of the present invention;

2 is a structural block diagram of a content distribution network-based tampering intervention device provided by an embodiment of the present invention;

3 is a structural block diagram of a content distribution network-based tampering intervention system provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a tampering intervention system based on a content distribution network provided by an embodiment of the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

An embodiment of the present invention provides a method for tampering intervention based on a content distribution network. As shown in FIG. 1 , the method includes the following steps S101 to S106. It should be noted that the tampering intervention in the embodiment of the present invention includes tampering prevention and tampering recovery. In other words, the embodiment of the present invention can not only prevent the static file from being tampered with, but also restore the tampered static file.

Step S101, the CDN edge node receives a request message from the user terminal, where the request message requests a static file; the static file in this embodiment may be a static file newly released by the origin site or a static file that has expired in the cache;

Step S102, the CDN edge node determines the source station to be returned to the source, and initiates a back-to-source request; specifically, the source station monitoring module of the CDN edge node may determine which source station to return to;

Step S103, the CDN edge node receives the response message of the source station, and sends the response message to the user terminal;

Step S104, the CDN edge node judges whether the static file in the response message has been tampered with;

Step S105, if it has not been tampered with, cache the static file;

Step S106, if the static file is tampered with, the static file is not cached, and when the message requesting the static file is received again, the CDN edge node re-initiates the source back request. If no tampering occurs, the CDN edge node caches the static file of the normal response to achieve tampering recovery.

In the method of the above embodiment, when the user requests a static file newly released by the origin site or caches an expired static file, the CDN edge node adds a step of judging whether the file has been maliciously tampered with. If there is no malicious tampering, the file will be cached normally. If the file is tampered with, the file will not be cached. When subsequent users continue to access the file, they need to go back to the origin and request again. When the origin site responds normally and there is no tampering between the origin site and the CDN edge node, the tampering is restored. CDN edge nodes can detect maliciously tampered files in time by judging, and do not cache maliciously tampered files; there is no need to wait for the cache to expire before maliciously tampered recovery, as long as the user requests the file next time, maliciously tampered recovery can be performed, shortening the time To save the time for tampering and recovery, abnormal data can be recovered in time to ensure user experience.

The embodiments of the present invention provide the following two methods for the CDN edge node to determine whether a static file has been tampered with, which will be described separately below.

(1) Determine the feature value obtained from the response message multiple times. The specific steps are as follows: the CDN edge node determines whether it is the first time to receive the request message requesting the static file; if not, the CDN edge node from the corresponding at least two At least two first feature values are obtained from the response message; the CDN edge node determines whether the at least two first feature values are consistent; if they are consistent, it is determined that the static file has not been tampered with; if they are inconsistent, it is determined that the static file has been tampered with.

The method is based on probability statistics, that is, the tampering phenomenon is occasional and unpredictable. If the CDN edge node receives the request message requesting the static file for the first time, according to this method, the acquired static file is not cached, and waits for subsequent users to request the static file, so as to obtain the static file from the source again, so as to determine the two Whether the eigenvalues of one or more times are consistent.

Specifically, the above-mentioned first characteristic value may be the MD5 value of the static file (Message Digest AlgorithmMD5, that is, the fifth edition of the message digest algorithm), or other values that will change after the static file is tampered with, so that the characteristic value can be passed in time. changes, determine that static files have been tampered with.

Using this method to determine whether a static file has been tampered with can shorten the recovery time of abnormal files. For example, a file whose cache time is 1 day does not need to wait for 1 day before malicious tampering is restored. As long as the user requests the file next time, malicious tampering is performed. recovery, greatly reducing the data recovery time.

(2) The CDN edge node and the source station negotiate a calculation method. Both the CDN edge node and the source station use this calculation method to calculate the characteristic value. The CDN edge node compares the value calculated by itself with the value calculated by the source station to confirm the file. uniqueness. The specific steps are as follows: the CDN edge node extracts the second feature value carried in the response message, wherein the second feature value uniquely identifies the static file, and is calculated by the source station using the calculation method negotiated with the CDN edge node in advance; the CDN edge node uses the In the calculation method, the third characteristic value is calculated according to the response message; the CDN edge node judges whether the second characteristic value and the third characteristic value are consistent; if they are consistent, it is determined that the static file has not been tampered with;

Specifically, the second feature value calculated by the source station may be carried in the response header. For example, the second characteristic value and the third characteristic value may be calculated according to the len information obtained from the http header of the response message and the MD5 value of the file.

This method is based on the calculation method negotiated in advance. If the value calculated by the CDN edge node is inconsistent with the value calculated by the origin site, it is determined that the static file has been tampered with, and the static file is not cached. When subsequent users continue to request access to this file, repeat the process. The above process of returning to the source and judging whether it has been tampered with will not cache the file until the two values are consistent. Using this method to determine whether a static file has been tampered with can be uniquely confirmed, ensuring that the CDN edge node will not cache files that have been maliciously tampered with, and greatly shortening the tampering recovery time.

In the actual network environment, there may be multiple CDN nodes between the source station and the user terminal. In the process of the user requesting files to the CDN edge node and returning to the source to obtain the files, the transmission of these multiple CDN nodes is required. The link is not controllable, and there is also the possibility of tampering with files.

Considering this situation, the preferred embodiment of the present invention provides an implementation method for preventing files transmitted between CDN nodes from being tampered with. Specifically, the CDN edge node sending a response message to the user terminal includes: the CDN edge node utilizes multiple The preset private protocol between CDN nodes processes the response message, and the processed response message cannot be recognized by other devices; the CDN edge node transmits the processed response message through multiple CDN nodes; when the CDN edge on the user terminal side When the node receives the processed response message, it restores the processed response message by using a preset private protocol, and sends the restored response message to the user terminal.

This preferred embodiment transmits data between multiple CDN nodes through a preset private protocol. It can be intuitively understood that a tunnel is built between multiple CDN nodes, and the content in the tunnel is displayed as garbled externally, that is, it cannot be recognized by other devices. This can ensure that the content transmitted between CDN nodes will not be maliciously tampered with, and at the same time, it can effectively modify the congestion policy in time for network conditions, improve transmission speed and stability, and ensure user experience. In addition, in combination with the above-mentioned method (1) or (2) for judging whether a file has been tampered with, the entire link can be ensured that the content will not be maliciously tampered with.

The embodiment of the present invention also provides a tampering intervention device based on a content distribution network, which is applied to a CDN edge node and can be used to implement the foregoing tampering intervention method. For specific implementation details, refer to the foregoing method embodiments. As shown in FIG. 2 , the apparatus includes: a first receiving unit 21 , a back-to-source unit 22 , a second receiving unit 23 , a first sending unit 24 , a judging unit 25 , a buffering unit 26 and a processing unit 27 .

The first receiving unit 21 is configured to receive a request message from the user terminal, where the request message requests a static file newly released by the origin site or a static file whose cache has expired;

The back-to-source unit 22, connected to the first receiving unit 21, is used to determine the back-to-source source station and initiate a back-to-source request;

The second receiving unit 23 is connected to the back-to-source unit 22, and is used for receiving the response message of the source station;

The first sending unit 24, connected to the second receiving unit 23, is used for sending the response message to the user terminal;

The judging unit 25 is connected to the second receiving unit 23, and is used for judging whether the static file in the response message has been tampered with;

The cache unit 26, connected to the judgment unit 25, is used to cache the static file under the condition that it has not been tampered with;

The processing unit 27 is connected to the judging unit 25, and is used to not cache the static file in the case of being tampered with. When the message requesting the static file is received again, the back-to-origin request is re-initiated. If the source station returns a normal response In addition, there is no tampering between the origin site and the CDN edge node, and the static file of the normal response is cached to achieve tampering recovery.

It should be noted that the first receiving unit 21 and the second receiving unit 23 in the embodiment of the present invention may also be combined into one receiving unit, and the combined receiving unit receives the request message of the user terminal and the response of the source station. message; at this time, it can also be regarded that the combined receiving unit includes the first receiving unit 21 and the second receiving unit 23 . Therefore, whether to combine the first receiving unit 21 and the second receiving unit 23 into one receiving unit can be set according to actual needs, which is not limited in the present invention.

In the device of the above embodiment, the CDN edge node can timely find out that the file has been maliciously tampered with by judging, and does not cache the maliciously tampered file; it does not need to wait for the cache to expire before performing malicious tampering recovery, as long as the user requests the file next time. The recovery of malicious tampering shortens the time for tampering and recovery, and restores abnormal data in time to ensure user experience.

In one embodiment, the judging unit 25 includes: a first judging module for judging whether it is the first time to receive a request message requesting a static file; an obtaining module, connected to the first judging module, for when it is not the first time to receive a request message , respectively obtain at least two first characteristic values from the corresponding at least two response messages; the second judgment module, connected to the obtaining module, is used to judge whether the at least two first characteristic values are consistent; the first determination module is connected to The second judging module is configured to determine that the static file has not been tampered with in the case of consistency; and determine that the static file has been tampered with in the case of inconsistency. The judging unit 25 in this embodiment is applicable to the above-mentioned method (2) for judging whether a static file has been tampered with.

The judging unit 25, which is applicable to the above-mentioned method (3) for judging whether a static file has been tampered with, includes: an extraction module, configured to extract the second characteristic value carried in the response message, wherein the second characteristic value uniquely identifies the static file, and is determined by the source The station is calculated by using the calculation method negotiated with the CDN edge node in advance; the calculation module is used to calculate the third eigenvalue according to the response message by using the calculation method; the third judgment module is connected to the calculation module and the extraction module, and is used to judge the first Whether the second characteristic value is consistent with the third characteristic value; the second determining module, connected to the third determining module, is used to determine that the static file has not been tampered with in the case of consistency; and in the case of inconsistency, determine that the static file has been tampered with .

It should be noted that the judging unit 25 in the embodiment of the present invention may also not include the first judging module, the second judging module, and the first determining module, and directly judge whether the request for a static file is received for the first time through the judging unit 25. message; obtain at least two first characteristic values from the response message and determine whether the at least two first characteristic values are consistent; and be used to determine that the static file has not been tampered with in the case of consistency, and to determine in the case of inconsistency Static files are tampered with.

In addition, the judgment unit 25 may not include the extraction module, the calculation module, the third judgment module, and the second determination module, and directly extract the second feature value carried in the response message through the judgment unit 25, wherein the second feature The value uniquely identifies the static file; the third characteristic value is calculated according to the response message by using the calculation method negotiated with the source station, and the calculation method is the calculation method negotiated with the CDN system in advance by the source station; Whether the third characteristic value is consistent; and is used to determine that the static file has not been tampered with in the case of consistency, and determine that the static file has been tampered with in the case of inconsistency.

Therefore, whether the judging unit 25 includes a first judging module, a second judging module, a first judging module, a fetching module, a calculating module, a third judging module, and a second judging module can be set according to actual needs. This is not limited.

Preferably, the first sending unit 24 includes: a processing module configured to process the response message by using a preset private protocol between the multiple CDN nodes when there are multiple CDN nodes between the source station and the user terminal, The processed response message cannot be recognized by other devices; the transmission module, connected to the processing module, is used to transmit the processed response message through multiple CDN nodes; the restoration module is used to receive the received response message as the CDN edge node on the user terminal side. When the processed response message is processed, the processed response message is restored by using a preset private protocol, and the restored response message is sent to the user terminal. This ensures that the content transmitted between CDN nodes will not be maliciously tampered with.

An embodiment of the present invention further provides a tampering intervention system based on a content distribution network. As shown in FIG. 3 , the system includes: a user terminal 10 , a CDN edge node 20 and a source station 30 .

The user terminal 10 is configured to send a request message, where the request message requests a static file newly released by the origin site or a static file whose cache has expired;

The CDN edge node 20, connected to the user terminal 10, includes the tampering intervention device based on the content distribution network described in the above embodiment;

The source station 30, connected to the CDN edge node 20, includes: a third receiving unit 31 for receiving a back-to-source request sent by the CDN edge node 20; a second sending unit 32, connected to the third receiving unit 31, for sending the CDN The edge node 20 sends a response message.

In the system of the above embodiment, the CDN edge node can timely find out that the file has been maliciously tampered with by judging, and does not cache the maliciously tampered file; there is no need to wait for the cache to expire before the malicious tampering can be recovered, as long as the user requests the file next time. The recovery of malicious tampering shortens the time for tampering and recovery, and restores abnormal data in time to ensure user experience.

Preferably, the source station 30 may further include: a computing unit, connected to the third receiving unit 31, configured to obtain a feature value uniquely identifying the static file by using a computing method negotiated with the CDN edge node in advance, and place the feature value in the in the response message.

The solution of the present invention will be described in detail below with reference to FIG. 4 .

As shown in FIG. 4 , there are multiple CDN nodes between the user terminal 10 and the source station 30. The user requests a static file, the user terminal 10 sends the request to the CDN edge node 20A, and the CDN edge node 20A sends the request to the CDN edge node through a preset private protocol. 20B forwards the request; CDN edge node 20B returns to the origin station 30 to obtain the static file, uses the above method (1) or (2) to determine whether the static file has been tampered with, to decide whether to cache the file, and sends the response through a preset private protocol To the CDN edge node 20A.

If it is determined that the static file has been tampered with, the CDN edge node 20B does not cache the static file, and the CDN edge node 20A processes the received response to obtain a static file that can be identified by the user terminal 10, and returns the static file to the user terminal 10. , and do not cache the static file, and subsequent users will still make back-to-origin requests to access the file.

If it is determined that the static file has not been tampered with, the CDN edge node 20B caches the static file. The CDN edge node 20A processes the received response, obtains a static file that can be identified by the user terminal 10, returns the static file to the user terminal 10, and caches the response at the same time. If subsequent users continue to access, the cached response is directly sent to the user. .

The device embodiments described above are only illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed over multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution in this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

From the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and certainly can also be implemented by hardware. Based on this understanding, the above-mentioned technical solutions can be embodied in the form of software products in essence or the parts that make contributions to the prior art, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic A disc, an optical disc, etc., includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the methods described in various embodiments or some parts of the embodiments.

The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection of the present invention. within the range.

Claims (15)

1. a tampering intervention method based on content distribution network, is characterized in that, comprises: The CDN edge node of the content distribution network receives a request message from the user terminal, wherein the request message requests a static file; The CDN edge node determines the source station of the back-to-source, and initiates a back-to-source request; The CDN edge node receives the response message of the source station, and sends the response message to the user terminal; The CDN edge node determines whether the static file in the response message has been tampered with; If it has not been tampered with, cache the static file; If it is tampered with, the static file will not be cached. When receiving a message requesting the static file again, the CDN edge node will re-initiate a back-to-origin request. If the origin site returns a normal response and the origin No tampering occurs between the station and the CDN edge node, and the CDN edge node caches the static file of the normal response to realize tampering recovery. 2. The content distribution network-based tampering intervention method according to claim 1, wherein the CDN edge node determines whether the static file in the response message is tampered with, comprising: The CDN edge node obtains at least two first feature values from corresponding at least two response messages respectively; The CDN edge node judges whether the at least two first feature values are consistent; If it is consistent, it is determined that the static file has not been tampered with; If not, it is determined that the static file has been tampered with. 3. The tampering intervention method based on content distribution network as claimed in claim 2, is characterized in that, also comprises: When determining whether the at least two first characteristic values are consistent, the CDN edge node first determines whether it is the first time that a request message for requesting the static file is received. 4. The content distribution network-based tampering intervention method according to claim 1, wherein the CDN edge node determines whether the static file in the response message has been tampered with, comprising: The CDN edge node extracts the second feature value carried in the response message, wherein the second feature value uniquely identifies the static file; The CDN edge node uses the calculation method negotiated with the source station to calculate and obtain the third characteristic value according to the response message; The CDN edge node determines whether the second eigenvalue is consistent with the third eigenvalue; If it is consistent, it is determined that the static file has not been tampered with; If not, it is determined that the static file has been tampered with. 5. The content distribution network-based tampering intervention method of claim 4, wherein the CDN edge node determines whether the static file in the response message has been tampered with, comprising: The negotiated calculation method is a calculation method negotiated by the source station with the CDN system in advance. 6. The content distribution network-based tampering intervention method according to any one of claims 1 to 5, wherein if there are multiple CDN nodes between the source station and the user terminal, the CDN edge The node sending the response message to the user terminal includes: The CDN edge node processes the response message by using a preset private protocol among the multiple CDN nodes; The CDN edge node transmits the processed response message through the multiple CDN nodes; When the CDN edge node on the user terminal side receives the processed response message, it restores the processed response message by using the preset private protocol, and sends the restored response message to the user terminal. 7. A tampering intervention device based on a content distribution network, applied to a CDN edge node of a content distribution network, wherein the device comprises: a receiving unit, configured to receive the request message of the user terminal and the response message of the source station; The back-to-source unit is used to determine the back-to-source origin station and initiate a back-to-source request; a first sending unit, configured to send the response message to the user terminal; a judging unit for judging whether the static file in the response message has been tampered with; a cache unit, configured to cache the static file without being tampered with; A processing unit, configured to not cache the static file in the case of being tampered with, and re-initiate the back-to-origin request when the message requesting the static file is received again, if the origin site returns a normal response And no tampering occurs between the source station and the CDN edge node, and the static file of the normal response is cached to realize tampering recovery. 8. The content distribution network-based tampering intervention device according to claim 7, applied to a CDN edge node of a content distribution network, wherein the device comprises: The receiving unit includes a first receiving unit and a second receiving unit, wherein the first receiving unit is configured to receive a request message from a user terminal; the second receiving unit is configured to receive a response message from the source station. 9. The tampering intervention device based on a content distribution network according to claim 7, wherein the judging unit comprises: a first judging module for judging whether it is the first time that a request message requesting the static file is received; an obtaining module, configured to obtain at least two first characteristic values from the response message; a second judgment module, configured to judge whether the at least two first characteristic values are consistent; A first determining module, configured to determine that the static file has not been tampered with in the case of consistency; and determine that the static file has been tampered with in the case of inconsistency. 10. The tampering intervention device based on a content distribution network according to claim 7, wherein the judging unit is configured to judge whether it is the first time to receive a request message requesting the static file; obtain from the response message at least two first feature values and judging whether the at least two first feature values are consistent; and in the case of consistency, determining that the static file has not been tampered with, and in the case of inconsistency, determining the static file The file has been tampered with. 11. The tampering intervention device based on a content distribution network according to claim 7, wherein the judging unit comprises: an extraction module, configured to extract the second characteristic value carried in the response message, wherein the second characteristic value uniquely identifies the static file; a calculation module, configured to obtain a third eigenvalue according to the response message by using a calculation method negotiated with the source station, and the calculation method is a calculation method negotiated with the CDN system in advance by the source station; a third judgment module, configured to judge whether the second characteristic value is consistent with the third characteristic value; The second determining module is configured to determine that the static file has not been tampered with in the case of consistency; and determine that the static file has been tampered with in the case of inconsistency. 12. The tampering intervention device based on a content distribution network according to claim 7, wherein the judging unit is configured to extract the second characteristic value carried in the response message, wherein the second characteristic value is unique Identifying the static file; for obtaining a third characteristic value by calculating the response message according to the calculation method negotiated with the source station, and the calculation method is the calculation method negotiated with the CDN system in advance by the source station ; for judging whether the second characteristic value is consistent with the third characteristic value; and for determining that the static file has not been tampered with in the case of consistency, and determining that the static file is inconsistent in the case of inconsistency tampered with. 13. The tampering intervention device based on a content distribution network according to any one of claims 7 to 12, wherein the first sending unit comprises: A processing module, configured to process the response message by using a preset private protocol between the multiple CDN nodes when there are multiple CDN nodes between the source station and the user terminal, and after processing The response message cannot be recognized by other devices; a transmission module, configured to transmit the processed response message through the multiple CDN nodes; The restoration module is configured to use the preset private protocol to restore the processed response message when the CDN edge node on the user terminal side receives the processed response message, and send the restored response message to the user terminal. 14. A content distribution network-based tampering intervention system, comprising: a user terminal, a content distribution network CDN edge node, and a source station, wherein, The user terminal is configured to send a request message, wherein the request message requests a static file; The CDN edge node comprises the content distribution network-based tampering intervention device according to any one of claims 7 to 11; The origin site includes: a third receiving unit, configured to receive a back-to-source request sent by the CDN edge node; The second sending unit is configured to send a response message to the CDN edge node. 15. The content distribution network-based tampering intervention system according to claim 14, wherein the source station further comprises: A computing unit, configured to obtain a characteristic value uniquely identifying the static file by using a calculation method negotiated with the CDN edge node in advance, and place the characteristic value in the response message.