One or more <hash/> elements MUST be present when offering a file, but those elements MAY be empty if the hash has not yet been computed. If there is no computed hash value, the <hash/> element(s) MUST possess an 'algo' attribute specifying which hash algorithm will be used. Once a hash has been calculated by the File Sender, the File Sender SHOULD inform the File Receiver of the hash value as described in Checksum.
+One or more <hash/> elements MUST be present when offering a file, but those elements MAY be empty if the hash has not yet been computed. If there is no computed hash value, the <hash/> element(s) MUST possess an 'algo' attribute specifying which hash algorithm will be used. Once a hash has been calculated by the File Sender, the File Sender SHOULD inform the File Receiver of the hash value as described in Checksum.
Additional elements MAY be included as children of the <file/> element to provide additional metadata about the file, such as &xep0264;.
The optional <range/> element MAY possess two attributes: