Encryption method, decryption method, and related apparatus

A decryption method, comprising:

• receiving an initial layer-3 message, wherein the initial layer-3 message comprises a part of data that is encrypted, and an encryption indication;
• generating a keystream according to the encryption indication, wherein the keystream is used to decrypt the part of data in the initial layer-3 message;
• and
• generating, by performing an exclusive OR operation on the keystream and the initial layer-3 message, a second initial layer-3 message in which the part of data is decrypted.

An encryption apparatus, comprising a processor and a transmitter,

• wherein the processor is configured to:
• generate a first keystream, wherein the first keystream is used to encrypt a part of data in an initial layer-3 message;
• and
• generate, by performing an exclusive OR operation on the first keystream and the initial layer-3 message, an second initial layer-3 message in which the part of data is encrypted;
• and
• the transmitter is configured to send the second initial layer-3 message to a network equipment;
• wherein the second initial layer-3 message comprises an encryption indication, and the encryption indication is used to indicate that the part of data in the second initial layer-3 message is encrypted.

A decryption apparatus, comprising a receiver and a processor,

• wherein the receiver is configured to receive an initial layer-3 message, wherein the initial layer-3 message comprises a part of data that is encrypted an encryption indication;
• and
• wherein the processor is configured to:
• generate a keystream according to the encryption indication in the initial layer-3 message, wherein the keystream is used to decrypt the part of data contained in the initial layer-3 message;
• and
• generate, by performing an exclusive OR operation on the keystream and the initial layer-3 message, a second initial layer-3 message in which the part of data is decrypted.