SMB protocol file restoration method and system

The invention provides an SMB protocol file restoration method and system, and the method comprises the steps: obtaining the restoration file field information of a message through obtaining a restoration instruction of a target file, i.e., the direction request direction of the message, storing the restoration file field information to a session control structure, and enabling the restoration file field information to at least comprise an interaction message number and a file offset. If the direction is the response direction, matching other restoration file field information in the restoration file field information through the interaction message number; writing a file block of the request direction message or the response direction message into a memory according to the file offset; and if the total length of the written file blocks in the memory is the same as the total length of the file in the corresponding restored file field information, representing that the restoration of the target file is complet