Source Technologies ST9530 manual DES and AES Decryption, Decryption Commands

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DES and AES Decryption

Data Encryption Standard (DES) and the Advanced Encryption Standard (AES) are both supported in the Source Technologies Secure MICR Printers. The minimum Code Level support for AES is 8.5j. Levels 8.5i. and lower only support DES.

DES originated at IBM in 1977 and was adopted by the U.S. Department of Defense. The controlling standards for DES are ANSI X3.92 and X3.106 and in the Federal FIPS 46-3 standard. An alternative to DES called Triple DES is not supported in our Secure MICR printers.

AES is documented in a Federal Information Processing Standard (FIPS) standard FIPS 197, dated 11/26/2001. Three key sizes are documented in the standard, 128-bit, 192-bit, & 256-bit. We currently only support the most commonly used 128-bit key size.

The algorithm selected for AES is Rijndael. Developed in Belgium, an English pronunciation alternative is “Rain Doll”. In addition to U.S. Government implementations, it is anticipated AES will be adopted by businesses, organizations, institutions, and individuals outside of government, and outside of the United States as was the case for DES.

We only support decryption for DES and AES. Encrypted printer data streams can be decrypted using the key stored some time prior to the message. Keys for both DES and AES are stored separately so that both AES and DES are supported simultaneously. The keys messages themselves can be encrypted with either DES or AES for either DES or AES. Only one DES and one AES key exists at any one point in time. Old keys are not saved. To change either a DES or an AES key requires the MICR Password Command.

The Secure MICR printer does not have any capability to encrypt a return or Bi-directional message.

Decryption Commands

Decryption requires printer processing overhead. In our testing encrypted printer data steams near or below 100K bytes per page do not seem to affect printer speed in term of pages per minute or first page out timings. Some testing done with print files from 500K to 1 Meg per page showed up to a 30% degradation in speed. It is therefore recommended the encryption be reserved for the confidential portions of the data when large file sizes are anticipated.

Set DES Decryption Key Command &%STSETDESKEY<16 Hex Characters>$

The command requires a MICR Password Command be sent prior to the Key Command. The Key Command could itself be encrypted and then decrypted in the printer. The command requires the key data be in a double-byte hex format. The 8 byte value must be converted to the 16 byte format. The only values that can be contained in the 16 command

Secure MICR Printer User’s Guide

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© Source Technologies

September 2005

All Rights Reserved

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Contents ST9530 Secure Micr Printer User’s Guide Page Table of Contents Error Messages Audit Trail ReportPrinter Installation Check Processing System Micr OverviewMicr Printing Today Secure Micr Printer User’s Guide General Features of Check Design Position and Dimension GaugeMicr Check Design Design Elements in Detail PaperDuplexing Micr Clear BandData Elements Date Amount Convenience AmountAmount In Words Payee AreaSignature Area Drawee Institution NameMemo Line Check Serial Number Fractional Routing Number Micr LineAuxiliary On-Us Field Positions 65 to External Processing Code EPC Field PositionOn-Us Field Positions 32 to Sample Check Quality Issues Weight Micr Check StockQuality LayoutSecurity Issues Check Stock Security FeaturesSecurity Note Secure Micr Printer User’s Guide Micr Features Micr ModeMicr Fonts Secure FontsBi-Directional Feedback MicroPrint@PJL Ustatus Device CODE=40020 Resource Storage Micr MenuEntering Micr Mode STF CommandSTH Command PasswordMicr Definition Command SMCPxxxx$ optional SmcpSet New Password Command &%STExxxxxxxx$ STESTS Print Micr E-13B Font SMDddd...ddd$Print Micr CMC7 Font SM7ddd...ddd$ Print Secure Numeric Font SMFddd..ddd~Print ICR Secure Numeric Font &%SMIxxxxxx~ Print MicroPrint Line SMMxxxxxxxxx!$Secure Flash Resource Unlock Command STPxxxxx$ Tray Lock Command STTL#$Load Flash Resource STLxxxxxyyyyyyzdd....dd Format Flash Memory SFF$Tray Unlock Command STTU#$ Tray Swapping CommandsSTTU# SttsonDecryption Commands DES and AES DecryptionTurn DES Decryption on Turn AES Decryption onTurn DES Decryption OFF Turn AES Decryption OFFCustomer Character Conversation Command STBEEP1$ Special Alert and Custom Beep CommandSTBEEP2$ MICRpoint Feature Secure Micr Printer User’s Guide IBM Host Programming Features and Examples Hex TransferTurning Hex Transfer On Turning Hex Transfer OffHex Transfer Examples Micr Mode Command Example Commands in .1 in order of appearance STFPASSWORD$Command terminator Micr font character mapping in Appendix aEscape Character Translation STY4040$STY4000$ Example &%STY2300$Sample Check Audit Trail Reports Audit Trail Report Command Set Print Audit ReportSAR End Audit RecordAudit Report Field One SQ1d..d$ Audit Report Field Two-MICR LineAudit Report Field Three SQ3d..d$ Audit Report Field Four SQ4d..d~Audit Report Field Five SQ5d..d$ Audit Report Field Six SQ6d..d$Audit Report Field Seven SQ7d..d$ Print and Purge Audit Report &%SPURGExx$Start Audit Feedback Command Print Audit Report SPRINTxx$Audit Trail Commands Example Audit Trail Check Sample SAR$ SQ1200$200SQ6October 5, 2005$ TerminatorSMD...$ SQ7103345 AM$Msmith Error Messages Error Message on Display Printed MessageDescription ActionMacro Definition Error Invalid decode Page Appendix a E13B Micr Font Mapping Command&%SMDddd..ddd$ Example &%SMD 00001234 T01234567T3210987654321$ Will printAppendix B CMC7 Micr Font Mapping Less Than Equal Greater Than Appendix C Secure Numeric Font Mapping Description Alpha/Numeric Hex Value Secure Font CharacterTwo Three Four Five Six Seven Eight Nine Arrow Example&%SMF$15,575.00~ Appendix D ICR Secure Numeric Font Mapping Appendix E Micr Mode Command Summary STTSOFF$ SPRINT$ STORE$SPURGE$ Previous Audit Report information will be lostAppendix G PJL Based Micr Commands PJL Re-Lock Sequence With a New Password Value UEL @PJL Info MicrCartridge Status = Unknown PCL Font Calls, Positioning Commands and Variable Print Data Sample Accounts Payable Check PJL and PCL commands used to print the sample check ESC%-12345X@PJL Ldeletepassword LRESOURCEflash
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