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Test Results for Software Write Block Tools: PDBLOCK Version 2.10

NCJ Number
Date Published
June 2005
93 pages
This report presents findings from testing the software write block tool PDBLOCK Version 2.10 against Software Write Block Tool Specification and Test Plan Version 3.0.
The Software Write Block Tool Specification and Test Plan Version 3.0 requires that a top-level software write block tool not allow a protected drive to be changed, not prevent obtaining any information from or about any drive, and not prevent any operations to a drive that is not protected. For all test cases run, the PD Block Version 2.10, a product of Digital Intelligence, Inc., blocked all commands from the write category sent to a protected drive; however, the tool did not block some commands from the miscellaneous category that were either undefined (invalid) or outmoded and not routinely used by current software. The tool only blocked three commands in the miscellaneous category: command code 0x1A, 0x22, and 0xED. The unblocked commands in current BIOS implementations do not write to a hard drive, but in the future they could be defined so they would change the contents or accessibility of a protected drive; therefore, in the test specification, these commands are included in categories that should be blocked. For all test cases run, the tool always allowed commands to obtain information from any protected drive. The tool always allowed any command to access any unprotected drives for all test cases run; however, for some test cases run with five drives, the fifth drive was protected even though it was not so designated. Extensive data tables

Date Published: June 1, 2005