2.2.42.1 SMB2_COMPRESSION_TRANSFORM_HEADER_UNCHAINED

This structure is used by the client or server when sending unchained compressed messages. This optional header is valid only for the SMB 3.1.1 dialect<80>.


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ProtocolId

OriginalCompressedSegmentSize

CompressionAlgorithm

Flags

Offset

ProtocolId (4 bytes): The protocol identifier. The value MUST be set to 0x424D53FC, also represented as (in network order) 0xFC, 'S', 'M', and 'B'.

OriginalCompressedSegmentSize (4 bytes): The size, in bytes, of the uncompressed data segment.

CompressionAlgorithm (2 bytes): This field MUST contain one of the algorithms used to compress the SMB2 message as specified in the CompressionAlgorithms field of section 2.2.3.1.3, except “NONE”.

Flags (2 bytes): This field MUST be set to one SMB2_COMPRESSION_FLAG_NONE (0x0000).

Offset (4 bytes): The offset, in bytes, from the end of this structure to the start of compressed data segment.