WO2012139427A1

WO2012139427A1 - Media message processing method, system and device

Info

Publication number: WO2012139427A1
Application number: PCT/CN2012/070249
Authority: WO
Inventors: 卢艳; 丁欣
Original assignee: 中兴通讯股份有限公司
Priority date: 2011-04-15
Filing date: 2012-01-12
Publication date: 2012-10-18
Also published as: CN102740246B; CN102740246A

Abstract

The present invention relates to a media message processing method, system and device. The method comprises: a sender using a key to encrypt one or more media contents, that is, partial media contents, in a media message to obtain a media ciphertext; the sender sending a media message carrying the media ciphertext; a receiver receiving the media message; and the receiver decrypting the media ciphertext to obtain the partial media contents. The media message processing method, system and device in the present invention increase the encryption and decryption speed and improve the user experience while improving the security of media messages.

Description

Media message processing method, system and device

Technical field

The present invention relates to the field of communications, and in particular, to a media message processing method (including encryption and decryption method), system and device (media message transmitting device and media message receiving device).

Background technique

Nowadays, multimedia messaging services, such as MMS, (mobile) email, and instant messaging services, have become more widely used.

Multimedia messages usually contain multiple media content. Sometimes, some media content is very important and sensitive content (such as text or pictures involving personal privacy or secrets). To prevent sensitive content from being learned by unauthorized objects, media messages can be Implement encryption. However, in some cases, media content affects the speed of encryption and decryption, especially encryption and decryption on mobile phone terminals with limited resources, which will affect the user experience.

Summary of the invention

The technical problem to be solved by the present invention is to provide a media message processing method, system and device, which solves the problem that the encryption and decryption speed is slow.

To solve the above technical problem, the present invention provides a media message processing method, and the method includes:

The sender encrypts one or more media contents in the media message, that is, the local media content, by using a key to obtain a media ciphertext;

Sending, by the sender, a media message, where the media ciphertext is carried;

Receiving, by the receiver, the media message;

The recipient decrypts the media ciphertext to obtain local media content.

Preferably, the message header of the media message carries the media ciphertext location parameter value, and the media body of the media message carries the media ciphertext. Preferably, before sending the media message, the sender encrypts the key with the public key of the receiver to obtain a key ciphertext, and carries the key ciphertext in the media message sent by the sender.

Preferably, before decrypting the media ciphertext, the receiver decrypts the key ciphertext by using a private key to obtain a key, and then decrypts the media ciphertext by using the key.

Preferably, the message header of the media message carries the key ciphertext.

Preferably, the content header of the media ciphertext carries the key ciphertext.

To solve the above technical problem, the present invention also provides a method for encrypting a media message, the method comprising:

The sender encrypts the media content by using the key to obtain the media ciphertext, and encrypts the key by using the public key of the receiver to obtain the key ciphertext;

The sender sends a media message, where the key ciphertext and the media ciphertext are carried.

Preferably, the media content is one or several media content (Content) to be encrypted in the media message or the media message.

Preferably, the message header of the media message further carries a media ciphertext location parameter value and a key ciphertext. Preferably, the key ciphertext is at a content header of the media ciphertext.

To solve the above technical problem, the present invention also provides a media message processing system, the system comprising:

The sender's encryption module is configured to: encrypt the media content by using the key to obtain the media ciphertext content, and encrypt the key by using the recipient public key to obtain the key ciphertext;

a sending module of the sending party, configured to: send a media message, where the key ciphertext and the media ciphertext are carried;

a receiving module of the receiver, configured to: receive the media message;

The decryption module of the receiver is configured to: decrypt the key ciphertext by using its private key to obtain the key, and decrypt the media ciphertext by using the key to obtain the media content.

Preferably, the message header of the media message carries the key ciphertext and the media ciphertext location parameter value.

Preferably, the content header of the media ciphertext carries the key ciphertext. In order to solve the above technical problem, the present invention also provides a media message sending device, the device comprising:

The encryption module is configured to: encrypt the media content by using a key to obtain a media ciphertext, and encrypt the key by using a public key of the recipient to obtain a key ciphertext;

And a sending module, configured to: send a media message, where the key ciphertext and the media ciphertext are carried.

Preferably, the message header of the media message or the content header of the media ciphertext carries the key ciphertext.

Preferably, the message header of the media message or the content header of the media ciphertext carries an encryption algorithm suite.

The present invention also provides a media message receiving apparatus, including:

a receiving module, configured to: receive a media message; the media message is obtained by encrypting the media content by a key, and the media message includes a key ciphertext obtained by encrypting the key by using a receiving public key;

And a decryption module, configured to: decrypt the key ciphertext by using a private key to obtain the key, and decrypt the media ciphertext by using the key to obtain the media content.

Preferably, the content header of the media ciphertext includes a corresponding key ciphertext.

The method, system and device of the embodiments of the present invention only encrypt important or sensitive media content that the sender believes need to be encrypted, and simultaneously use symmetric encryption and asymmetric encryption, and use a symmetric encryption method to locally encrypt the media message.釆 Encrypting the encryption key with an asymmetric encryption method improves the encryption and decryption speed while improving security. BRIEF abstract FIG. 1 is a flowchart of a method for processing a media message according to an embodiment of the present invention;

2 is a flowchart of a method for encrypting a media message according to an embodiment of the present invention;

FIG. 3 is a flowchart of a method for decrypting a media message according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a module of a media message processing system according to an embodiment of the present invention. Preferred embodiment of the invention

Considering that the media message also contains other insensitive media, it is considered to encrypt only the important and sensitive content in the media message, and not encrypt the other content, so in order to improve the encryption and decryption speed, the user is improved. Experience, the present invention provides a method of local encryption of media messages.

The encryption of local content in media messages can use symmetric encryption and asymmetric encryption. For asymmetric encryption, since the key does not need to be temporarily agreed by both parties, the public key of the other party can be used to encrypt the local media content.

For symmetric encryption, if there is another key agreement mechanism, the local media can also be encrypted using the key agreed by both parties. In addition to the above two methods, the present invention also provides the following method.

As is well known, the symmetric encryption method encrypts and decrypts faster, but the encryption and decryption use the same key; the asymmetric encryption and decryption uses different keys, the encryption key can be disclosed, and the decryption key can only be hidden by the user and others cannot It is learned that, therefore, public key encryption is relatively more secure than symmetric encryption. However, the current public key encryption and decryption algorithm is basically an operation between long integers, which involves a large number of modular exponential operations, so the calculation speed is very slow, and the symmetric encryption algorithm basically rotates and confuses the data. Compression and other bit operations, which are fast.

The media message processing method of the present invention comprises two parts of encryption and decryption. Obviously, the encrypted part has a correspondence with the decrypted part. In the present invention, only the important or sensitive media content that the sender thinks need to be encrypted is encrypted, and at the same time Using symmetric encryption and asymmetric encryption, using the symmetric encryption method to locally encrypt the media message; using the asymmetric encryption method to encrypt the encryption key, while improving the encryption and decryption speed, and reducing the key In the negotiation process, the security of encrypted information is improved. Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

Example 1

As shown in FIG. 1, the media message processing method of the present invention includes:

Step 101: The sender encrypts the media content by using a key to obtain a media ciphertext, and encrypts the key by using a receiver public key to obtain a key ciphertext;

The media content may be one or more media contents included in the media message, and the data format may be original media content or content encoded by the original media content (for example, some encoded data of the media content).

The sender encrypts the media content using a symmetric encryption (random) algorithm, and encrypts the key using an asymmetric encryption algorithm and the recipient public key. Preferably, the key is a random number whose length meets the security requirement. For example, the key length of the AES should be no less than 128 bits, usually 128 bits, 192 bits and 256 bits.

The above steps are the processing steps of the sender for the media content, and the sender may have one or more media content to be encrypted, and then process to generate a plurality of media ciphertexts, or the media content includes one or more media that can be processed together. Content (such as multiple pictures), the one or more media content processing generates a media ciphertext.

Step 102: The sender sends a media message, where the encryption algorithm suite, the media ciphertext, and the key ciphertext are carried.

One or more media ciphertexts can be carried in the media message.

The encryption algorithm suite includes the above-mentioned symmetric encryption algorithm and asymmetric encryption algorithm, such as (RSA-AES), where AES is a symmetric encryption algorithm, RSA is an asymmetric encryption algorithm, AES is a symmetric encryption algorithm, and advanced data encryption standard is An upgraded version of DES (Data Encryption Standard), selected by the US NIST publicly, formerly known as Rijndael.

Step 103: The receiver receives the media message.

Step 104: The receiver decrypts the key ciphertext by using its private key to obtain the key, and decrypts the media ciphertext by using the key to obtain the media content. The present invention is disclosed in detail below from the perspective of the sender and the receiver, respectively:

Example 2

The media message encryption method is implemented by the message sender, and the symmetric content is used to encrypt the important content in the media message. The asymmetric encryption method is used to encrypt the encryption key, and the symmetric encryption key is randomly generated. The asymmetric encryption key is The public key of the recipient. As shown in Figure 2, the sender performs the following steps:

Step 201: Encrypt the media content M by using the key k to obtain the ciphertext C;

Here, the media content M may be the encoded media data obtained by the sender selecting the media content to be encrypted and encoding the media content.

Select the encryption algorithm suite (such as RSA-AES, exemplified below), and generate a random number k whose length meets the security requirement. The sender encrypts M using the key k and a symmetric encryption algorithm (such as AES) to obtain the media. Ciphertext C.

Step 202: Encrypt the key k by using a public key of the receiver to obtain a ciphertext k';

The sender encrypts k using the recipient's public key kB and a public key cryptographic algorithm (such as RSA), and the key ciphertext is recorded as k'.

Step 203: Send a media message carrying an encryption algorithm suite (such as RSA-AES), k, C, and other contents of the media message. Embodiment 3 The media message decryption method is implemented by the message receiver, and the ciphertext k' is decrypted using the receiver private key to obtain k, and the ciphertext C is decrypted by using k. As shown in FIG. 3, the receiver performs the following steps:

Step 301: The receiving party receives the media message, and extracts or separates the media message carrying the encryption algorithm suite (such as RSA-AES), the key ciphertext k', and the media ciphertext C;

Step 302: Decrypt k by using the private key of the receiver to obtain k, and the algorithm is the same as the algorithm of the sender encrypting k, such as RSA;

Step 303: decrypting C by k to obtain M, and the decryption algorithm is the same as the algorithm of the sender encrypting M, and the ratio is AES;

The following is a MIME media message package as a specific embodiment, which details the local content of the media message plus The secret method. Specifically, in the foregoing Embodiments 1 to 3, how the media message carries the above encryption algorithm suite, the key ciphertext (k'), the media ciphertext C, and the like, two preferred implementation schemes are given below:

Solution 1: The message header of the media message carries the encryption algorithm suite, the key ciphertext and the encrypted media location parameter value, and the location parameter value indicates the location of the encrypted media content (ie, the media ciphertext) in the message.

Take MIME media messages as an example:

The sender inserts a domain name indicating local encryption (such as Content-Encryption) in the MIME header of the media message to be sent.

An example of the message header is as follows:

Content-Encryption: suite = rsa-aes; ck 16 UEsDBBQ6AA9AAIAFKAoi7qOMOvLw0AAABWAAAUAAAAtuC0rr / a zaj QxbXE 1 LTC6y5kb2PtXHtwVNUZ81 / + 4 + kk3IQoAkBkRYQkSgbrKb7IYNEM69wmm6ckG0jCI0boZneTbJJ9sNlAEsdOt Fqd8Z846tQ6PhBl =; field = 0010: 1110 encrypted domain contains at least data: cipher suites (suite = rsa-aes), Encryption key

6y5kb2PtXHtwVNUZ81 +4+kk3IQoAffikRYQkSgbrKb7IYNEM69wmm6ckG0jCI0boZneTbJJ9sNlAEsdOtFqd8Z846tQ6

The position parameter values (field=0010:1110) in the message of PhBi) and ciphertext C are assigned as parameter values to the agreed parameter symbols.

The cipher suite (suite) refers to public key cryptography algorithms (such as RSA) and symmetric cryptographic algorithms (such as AES), which are used to encrypt symmetric encryption keys and encrypt important content that needs to be encrypted.

Preferably, the encryption indication information is added to the ciphertext Content header, for example, the content identification number content (Content) is as follows:

Content-Type: image/pjpeg-encrypted; name=UNKNOWN— PARAMETER— VALUE

Content-Disposition: attachment; filename="=?utf-8?B?5rW35bOh5bCB6Z2iMTExLkpQRw==?="

Content-ID :0010

C 『Note: This is the media ciphertext. Solution 2: The header of the content of the encrypted media content includes its corresponding encryption algorithm set. Piece and key ciphertext. Specifically, the sender inserts information indicating local encryption in the content (Content) of each media ciphertext C (for example, by using an extended field Content-Encryption, or carrying the information as another field, such as a parameter of Content-Type. ). In addition, the encryption indication information may be added to the head of the media content of the media ciphertext C.

Content-Type: image/pjpeg-encrypted; name=UNKNOWN— PARAMETER— VALUE

Content-Encryption: suite=rsa-3des; ck= 16 UEsDBBQ6AA9AAIAFKAoi7qOMOvLw0AAABWAAAUAAAAtuC0r r/azaj QxbXE 1 LTC6y5kb2PtXHtwVNUZ81 /+4+kk3IQoAkBkRYQkSgbrKb7IYNEM69wmm6ckG0jCI0boZneTbJJ9sNlAEs dOtFqd8Z846tQ6PhBl;

Content-ID :0010

C 『Note: This is the media ciphertext. The encrypted domain name contains at least the data: the encryption algorithm suite (suite=rsa-3des), the ciphertext k of the encryption key, and the cipher suite refers to a public key encryption algorithm (such as RSA) and a symmetric encryption algorithm (such as AES). Used to encrypt symmetric encryption keys and encrypt important content that needs to be encrypted;

If only one media content (such as a picture) is locally encrypted in the media message, the two schemes have the same effect, but if multiple media content (such as a picture and an audio) are needed, if the scheme one is used, then The picture and audio are encrypted with the same cipher suite. Accordingly, since the encoding method is at the head of the media content, different encoding methods can be used; if the second scheme is used, different encodings can be used. The cipher suite encrypts pictures and audio.

Although the present invention uses MIME media messages as a specific embodiment, the present invention is also applicable to media message partial content encryption in other media formats.

In order to implement the above method, the present invention also provides a media message processing system. As shown in FIG. 4, the system includes:

The encryption module of the sender is configured to encrypt the media content by using a key to obtain a media ciphertext, and encrypt the key by using a public key of the receiver to obtain a key ciphertext;

The sending module of the sender is configured to send a media message, where the key ciphertext is carried, Media ciphertext; Optionally, an encryption algorithm suite can also be carried.

a receiving module of the receiver, configured to receive the media message;

Decrypting module of the receiving party, configured to decrypt the key ciphertext by using its private key to obtain the key, and decrypt the media ciphertext by using the key to obtain the media content;

Specifically, there are two options for media messages:

In the first solution, the media message of the present invention is different from the existing media message in that: the message header of the media message carries the ciphertext and the location parameter value.

In the second solution, the media message of the present invention is different from the existing media message in that: the content of the content of the media content includes a corresponding encryption algorithm suite and a key ciphertext.

In addition, the present invention also provides a media message transmitting device (ie, a sender), the device comprising:

An encryption module, configured to encrypt the media content by using a key to obtain a media ciphertext, and encrypt the key by using a public key of the recipient to obtain a key ciphertext;

And a sending module, configured to send the media message, where the encryption algorithm suite, the key ciphertext, and the media ciphertext are carried.

Further, the message header of the media message carries the key ciphertext and the encrypted media location parameter value, and optionally, the encryption algorithm suite.

Alternatively, the header of the content in which the media content is located includes its corresponding key ciphertext, and optionally, a corresponding encryption algorithm suite.

The present invention also provides a media message receiving device (ie, a receiving party), a receiving module, configured to receive a media message, and a decrypting module, configured to decrypt the encrypted media in the media message;

And a decryption module, configured to decrypt the key ciphertext by using the private key to obtain the key, and decrypt the media ciphertext by using the key to obtain the media content.

Further, the message header of the media message carries the key ciphertext and the media ciphertext location parameter value, and optionally, the encryption algorithm suite.

Alternatively, the header of the content in which the media content is located includes its corresponding key ciphertext, and optionally, a corresponding encryption algorithm suite. The method, system and device of the invention use a symmetric encryption method to localize the media message; use an asymmetric encryption method to encrypt the encryption key, improve the encryption and decryption speed of the media message, and improve the security of the media message. Sexuality makes it impossible for an incorrect recipient to get a partial of a media message.

The method, system and apparatus of the present invention employ a symmetric encryption method. In addition to being suitable for local media encryption of media messages, the present invention is also applicable to the encryption of entire media messages.

For the symmetric encryption method, if there are other key agreement mechanisms, in the above solution, the key may not be carried. The cipher suite can also be negotiated by other negotiation mechanisms. The methods and steps will not be described again.

The invention can also directly encrypt the media content by using the receiving public key, and the ciphering suite can also adopt other agreed methods. This method is suitable for occasions where the media content is small. The methods and steps are not described again.

In the above method, the cipher suite can also adopt other conventions and conventions, and does not need to be carried in the message. One of ordinary skill in the art will appreciate that all or a portion of the steps described above can be accomplished by a program that instructs the associated hardware, such as a read-only memory, a magnetic disk, or an optical disk. Alternatively, all or part of the steps of the above embodiments may also be implemented using one or more integrated circuits. Correspondingly, each module/unit in the above embodiment may be implemented in the form of hardware or in the form of a software function module. The invention is not limited to any specific form of combination of hardware and software.

INDUSTRIAL APPLICABILITY The method, system, and apparatus of the embodiments of the present invention encrypt only media content that is considered to be encrypted by an important or sensitive sender, and simultaneously uses symmetric encryption and asymmetric encryption, and uses a symmetric encryption method to media messages. Local encryption; Encryption of encryption keys using asymmetric encryption methods improves security and speeds up encryption and decryption.

Claims

Claim

A method for processing a media message, the method comprising:

The sender sends a media message, where the media message carries the media ciphertext; and the receiver receives the media message;

The recipient decrypts the media ciphertext to obtain local media content.

The method of claim 1, wherein the message header of the media message carries the value of the media ciphertext location parameter, and the message body of the media message carries the media ciphertext.

The method according to claim 1 or 2, wherein, before the sender sends the media message, the key is encrypted by using a public key of the recipient to obtain a key ciphertext, and the key is secreted. The text is carried in a media message sent by the sender.

4. The method according to claim 3, wherein before the recipient decrypts the media ciphertext, the key ciphertext is decrypted by using a private key to obtain a key, and the key is used to decrypt the Media ciphertext.

5. The method of claim 3, wherein the message header of the media message carries the key ciphertext.

The method of claim 3, wherein the content header of the media ciphertext carries the key ciphertext.

7. A method of encrypting a media message, the method comprising:

The sender sends a media message, where the media message carries the key ciphertext and the media ciphertext.

8. The method of claim 7, wherein the media content is one or several media content (Content) to be encrypted in a media message or a media message.

The method according to claim 7 or 8, wherein the message header of the media message is also carried With media ciphertext location parameter value and key ciphertext.

10. The method of claim 7 or 8, wherein the key ciphertext is at a content header of the media ciphertext.

11. A media message processing system, the system comprising:

a sending module of the sending party, configured to: send a media message, where the media message carries the key ciphertext and the media ciphertext;

a receiving module of the receiver, configured to: receive the media message;

And a decryption module of the receiver, configured to: decrypt the key ciphertext by using a private key to obtain the key, and decrypt the media ciphertext by using the key to obtain the media content.

The system of claim 11, wherein the message header of the media message carries the key ciphertext and the media ciphertext location parameter value.

13. The system according to claim 11, wherein the content header of the media ciphertext carries the key ciphertext.

14. A media message sending device, the device comprising:

And a sending module, configured to: send a media message, where the media message carries the key ciphertext and the media ciphertext.

The device according to claim 14, wherein the message header of the media message or the content header of the media ciphertext carries the key ciphertext.

The device according to claim 14, wherein the message header of the media message or the content header of the media ciphertext carries an encryption algorithm suite.

17. A media message receiving apparatus, comprising:

a receiving module, configured to: receive a media message; the media message is obtained by encrypting the media content by using a key, and the media message includes: encrypting the key by using a receiving public key Key ciphertext;

18. The apparatus according to claim 17, wherein the message header of the media message carries the key ciphertext and the media ciphertext location parameter value.

The device according to claim 17, wherein the content header of the media ciphertext comprises a corresponding key ciphertext.

The device according to claim 17, wherein the message header of the media message or the content header of the media ciphertext carries an encryption algorithm suite.