| M-209 Home Page |
IntroductionMr Bart Preneel was contacted in 2001 by two colleagues of Leuven University to decrypt some ciphered messages. They were investigating at the request of the Belgian Parliament about "The Circumstances of the Murder of Patrice Lumumba". Mr Preneel described his efforts to solve these messages in an article published in "Lecture Notes in Computer Science", in 2003. The messagesMr Preneel decrypted several messages (11), but he published only two in his article. The second was particularly important because it has been sent a few days before the murder of Lumumba. 1st MessageBrazza 28b (stamp : 15-2-1961). Jacques to Nicolas 11150 HSMEO TDUYB ZJQZI VVRHP ELHIL FXUKQ MNAFF ZPWSE DOXPX NFPPA RNMXS RZPUG LBZAI MXNFC ZZSHR XVTZI DZABT LPEET CNHFV RSNUF CJTQI HUKYM XZWBG HTLMO SWLOH EVJLF NOFYV ROSYC WXDTE WVEXE ACKPT HSMEO 11150 Here the corresponding raw French plaintext: conti nueWi ntrig uesWi nquie tante sWtan tWleo WquWe ville Wjacq uesWb issec tWvou sWpri eWvou sWinf ormer Wdisc retem entWm issio nWexa cteWc onfie eWhub ertWs topWi ntere sseyx 2nd MessageLoos to Marliers 14 January 1961 11h00 AHQNE XVAZW IQFFR JENFV OUXBD LQWDB BXFRZ NJVYB QVGOZ KFYQV GEDBE HGMPS GAZJK RDJQC VJTEB XNZZH MEVGS ANLLB DQCGF PWCVR UOMWW LOGSO ZWVVV LDQNI YTZAA QIJDR UEAAV RWYXH PAWSV CHTYN HSUIY PKFPZ OSEAW SUZMY QDYEL FUVOA WLSSD ZVKPU ZSHKK PALWB SHXRR MLQOK AHQNE 11205 141100Here the English translation of plaintext : Top secret. Answer to your printex message. First. Nothing sent to Rusur. Can you sort this out. Second. Resume urgently plan Brazza with respect to Joseph. Third Mission Bomboko. See telex on this topic from the Belgian Embassy. Jules. Remark : "Joseph" was the code name for Patrice Lumumba. We do not know anything about the "Brazza" plan. In fact this message is quite ambiguous and does not allow to decide on the involvement of Belgium. DecryptmentMr Preneel analysed 11 PRINTEX telexes sent between the Ministry of African affairs in Belgium and Elisabethville (Katanga), Brazzaville and Rusur. For five of these telexes, the plaintext was known. The first step was to discover the cipher machine. Mr Preneel guessed it was a Hagelin cipher machine : a C-35/C-36 or a C-38/C-48 or a CX-52 because these machines can print the cipher or plain text (hence the name of PRINTEX). The length of indicator (5 characters) clearly pointed to the C-35/C-36 with 5 wheels (Mr Preneel used the word "rotor"). Attempts to reconstruct the internal setting failed. After this failure, Mr Preneel moved on to C-38. The Belgian Army lent him a M-209. Then he studied the Morris's attack from plain text. This method permitted to Mr Prennel to recover part of the internal key for the message of 15 February 1961. The plain text was certain because it came from tapes pasted on the telegram. With the help of the third part of message number 7, he recovered the whole key. But the procedure to get it was extremely hard. For example, the settings of one wheel were obtained only by exhaustive search. Why was it so difficult? Because the number of lugs opposite the wheels didn't follow the standard rules. For example, the displacement values of 1, 2 and 3 could not occur. Fortunately the same internal setting was used for other messages. They were decrypted by exhaustive search for all 101 million starting positions for the wheels. Each search requires only a few minutes on a PC. The criterion chosen to find the correct plaintext (and therefore the message key) is the number of spaces (letter W) present at more than 12%. Then a manual search for the word BISECT or BISSECT. Cryptographic detailsTransmission protocole1st Message : After call signs, there is a string : 11150. Here 11 means part 1 of 1 ; 150 means that the plaintext contains 150 characters. HSMEO is the indicator from which we can derive the External key (Mr Preneel called it "False key" or "Session key"). After the cryptogram, these two strings were repeated.IndicatorThe 6th wheel was always initialized in the same position as the 5th, then the indicator group was five characters long. Mr Preneel deduced that the Playfair cipher was used to encrypt these external keys. The Playfair key was a random permutation of 25 letters.
Examples: The Playfair table:
The fifth wheel start (which was the same that the sixth wheel start) is replaced in the indicator by the letter on the left in the Playfair table.
If the External key is "MERFJJ", the Indicator is "IQCAU"
( ME -> IQ, RF -> CA, J -> U ).
Remark: The letter "Y" wasn't used. Plain text preparation before encryption
The Interior keyThe lugs: 1-0 0-4 0-5 2-5 3-5 0-0 1-0 0-4 1-5 2-6 3-5 0-0 2-0 0-5 1-6 2-6 3-5 0-3 0-5 2-4 3-4 3-6 0-3 0-5 2-4 3-4 3-6The Pins: Wheel 26 : AB_D_F___JK_____Q_ST____Y_ Wheel 25 : _B_____H_JK___OP__STUV__Z Wheel 23 : ___D_FG___K_MN____S_UVX Wheel 21 : AB___FGH__KLM_OP__S_U Wheel 19 : __CD_F____KL_N__QRS Wheel 17 : ABC_EF____K_MN__QRemarks:
All MessagesThe final report was written in French and Flemish. We choose the French language to show headers and commentaries. We give here only the 11 messages (13 cryptograms because one message was in 4 parts) which were ciphered by M-209. The telex number 1,8,9 and 13 were ciphered with OTP method.0. Minaf s.n. (cachet: 28-12-1960): Loos a Marliere IQCAU HYWCD SXDLZ BVREA BFHJC RLDSB YHIDG VHKXX UYTHF WFYFV TJUKK UIMUH PNEAM UKQFO HJNLP PUBWW DEAAN UNSWS LUUZJ PAJIM KEGQB SUJFB ZCGMX IGWKU TGAAR XUUOS EPEIT BRHOB TTOOP SMPKX ZASNS GWUDE QAEAG EGKXD RUXGX SJEDM NKNMN OOXET WERMS VUILD HNWON CEOYO CDFVV PSRVG KHHDC MAOLP BUCCM VHXDY PFRVN TVGUS XYBWB GSHIH OVUOR CBGNS IUYZS CIAZY SARSU RMHLF VXZNA XDTVT CFDEW DUPCO EKRET IHNOA MIPVK BHINV APZSU SYPSS YIZHG HUWXX BYHXI FSVMU IQCAU 11355 281600 2. Brazza s.n. (cachet: 7-1-1961): Marliere a Loos 11110 LFOPS UCOAO XXAVW BXANX SESLY RRTKD BAQZK IQZWP TWJVA KRCSD TOLJZ UOQVC UCRRT NAGUM TZBRD BRXVW LMHOD SUYWR FSZDI HCNEE ZVXZI MVEWO OYJMQ LFOPS 3. Minaf 04010 (cachet: 10-1-1961): Loos a Marliere 04010 HVKLX WSMCW OIVCY WKSDT ARGIX TGZOD SBXOY JBPOC VTPFP GVZSG UXKFX GRCUI TVDIU WFDWQ ATXRP JKWXI VZHUX REIJD IKEHJ GHFES SAPXT MEICZ HLDAR VYUVE NAIKD AZRSQ UQGYA RDGRV APYVX SELPV OPRDN ECMUN LFOAM UGADT ARAKP RXUJF JGSAL SBURB KXTSR ONOOL VPZKC KUOCY FRLZW DSGTJ HVKLX 11215 101815 4. Brazza s.n. (cachet: 12-1-1961): Marliere a Loos 11100 EUSZF BTDAO NXBAB AICMH JWDSJ ZSSXT CPBGC IPNYI MEBQM SWTAR GMMTW RLJMK GHPLX ROHPA JNIBA IYLNR PGSHN EZPSN DZXKD NZABJ IOCLT EUSFO 5. Minaf s.n. (cachet: 14-1-1961): Loos a Marliere AHQNE XVAZW IQFFR JENFV OUXBD LQWDB BXFRZ NJVYB QVGOZ KFYQV GEDBE HGMPS GAZJK RDJQC VJTEB XNZZH MEVGS ANLLB DQCGF PWCVR UOMWW LOGSO ZWVVV LDQNI YTZAA OIJDR UEAAV RWYXH PAWSV CHTYN HSUIY PKFPZ OSEAW SUZMY QDYEL FUVOA WLSSD ZVKPU ZSHKK PALWB SHXRR MLQOK AHQNE 11205 141100 6. Minaf 06116/cab (cachet: 16-1-1961): Loos a Marliere QTFJR PXFSD WMWOH HIXVN UTVVP BFVLG LFRZC BKMEW FQWMV LZRON JYMNR XTQZM NWPXO YDOBZ GHYZD NRWQG OUIUH GKUYX UUMVV BCDBY XWPLY MBAJR TONZS ENAJB BHVNM TQZBL WQARM WJAUP DSOTA CZZTT FEHOE AZRPU HERJF XANPN VWXXA CPOXE UPOFW QSMIC AELDR UABIP QXLSG DRURY MQRUI VCPQV IOSTU JMBSJ VTZHU QAQAR EJQHU NSYPQ DURKC WVXBR IXZLJ DDTUO MTAEX RMUES GQHQV PJJJE KOIGT QFOWE EODRX MROKI NUIZC JGSJD MEWXR HZBIF BUDZD IXSJD QTFJR 11335 161710 7. Minaf s.n. (cachet: 25-1-1961): Loos a Smal (Ce Telex se compose de quatre parties) - Partie 1: SLVUL QKSYR CLFFR QYQDI ZDRQA AKRRK WXZXA OKHEU RYSXO JCJBF YJCGC QSARE ADKYV QXDZL SPOPF WXDYK SDFXM TFBGH JHFEJ IZTWN VLDVB JXNPB TEGDO UEFAR UJIHH YXPGR ZUUUJ CHGRG NQZNS VZYTY TJMVI OXZXG NCQAS PQRIN QYMUC ZPRIT LLDVP SFAXL LSUSM GDPRQ MKQQM APVCQ GLIYX PHNQB ZIYKM ZOINQ EUDDN HTDKN VSORV NAUKO XBJBT NBOCS UTZCE WKREJ BUESJ QYVOL FIFPH NYOZL LBETQ CMCJO OSCIZ FDZIU TOAFV QVABL LBKUQ RRSYR SLVUL 12325 25 1630 - Partie 2: CLENB WVAKP YYNYW YVTCJ SOLDJ MLQGW FTCFG LHVID PRMVR XEMWI JVSXP TJLLS ZGKBA ZTYHC HEONW ITIYV BTSAF XYWSC MYFJX XLMDY PXJFT MMLVL ATOVW XINES PYWNK MNIBR RAEAQ NATSP MDWMW LWQCH ATQSD CFRAW SFWUF QVDFK AMQSA WIHJN HUCET QCRQH YPXCC VVBVM GCBCH AFQOX XNZTB UEAMJ JFTUD FRQGQ HXOUT CRRGY RTILD KCFCN ZTAUC STCKZ BZTJK NZOQB RURMY WXGJR MEPMB MDLDM RYSAZ OIWYA CLENB 222295 251630 - Partie 3: FSDVS BPEZS UWEFU ITMSR HFBAQ CHNIL MRGOX QDXMV MZOFX DQZVS NKGRS SPJFT AEOZM JDMZD KQXGD ZLBLF ANJEM ZKWNQ OYODP TJUZS EVNQB MQBHS PXLZE BIOSF VWZQD VZCSQ HDKTE CQYYX QNQZO ATZXA KZWBN LWAXT VFWEX XXCBD VTFSB ENKGS AFNGW QKLUV QVSPR PJUYG KRVFC PXEYK DSIDO KFLFW CFHZR BZJIU VRNEI QMJDL YBITX NBFZT IDGVU FCDSC WPVAW RVXQI SLDVU WYSRN BRJOE IVMSM QNCFN WVXTT VBOVU FSWXG GKKAR PNTRA DPIOU EJVFE BLYVX RAWXN SODEQ USZGW TVSGD FOXNT ASUAZ XRAEB HVRWR FSDVS 12370 251700 Texte clair: MILIT AIREW AVECW LEOWE TWELI WXXWM EKWCA BLERW PARWR ETOUR WEVOL UTION WSITU ATION WETWD IFFIC ULTES WRENC ONTRE ESWXX WSUIS WINTE RRVEN UWPER SONNE LLEME NTWAU PRERE SWMIN ISTRE WPOUR WQUES TIONK WTRAI TEMEN TSWIM PAYES WAUXW EPOUS ESWIM PORTA NTESJ DECIS IONSW CONCE RNANN TWNOT REKWS ITATT IONWS ERONT WPRIS ESWCE WJOUR WXXWC OMCHE FWXXW BISEC TWXXW SECWP OURWC HEFWE TATWM AJORW GDWSU DWKAS AIWXX WZONW RETOU RWETR EWPRE VUWPO URWLE KWBWX - Partie 4: LMOSB JBSOU NNRXN SWJRT UVRGF IUONY JOYBU TEZPR DERVI ZQGJC PKDDQ TQCAG FIJPT AXJNR OPMET KFHLB HKDAF AQYDX NDDRT WVWOX BAYBU ZDJYF OXUMI OSJUY LNRAQ WKMCC YFTIC RBARI QIFKB ETNZO OFARZ HMNTX RZTNO QCSDR KFWZW EVVNW CRQPH LZPBV CMGCN PDOGV SMWYB VBFRH JBKMI HVJQK EDMFV WOOWJ XAUZQ JHECR LMOSB 22235 251700 10. Minaf 17531 (cachet: 31-1-1961): Loos a Marliere BRAHK TKZHY UBSXO NMXOW LPREG IVYRI XAVFO CVXFI USPHE OWWME IZUIV CPLAG OHVPD NRAXT XONXZ ROTZX PRDYV FGWNJ LZFXQ EJRVB JZPFH QCHNI USRUW SARMX QNFZA RXRDD EKKZM RPVYR XYCIR QBDUS TEZWI UDCGQ DNNCZ NOBGZ HIIWA QNOPC IVGBX BZXYN HCTEW OQHOZ MBLNQ RXLKJ TOLVY YDKNR NQMLD KJRJS BRAHK 11225 311700 11. Minaf 19502 (cachet: 2-2-1961): Loos a Smal DLEOE EPEUZ DJWEX HBAAJ TNWRJ AQUCM VJPVI VPWHQ UGIQW THNEO THBXA BVSJE JIOBQ ZMEQH QTNQG WQIUU RFXLF SSTDD QLLTY TPCIF ZNPJN HIMSJ WAUFO RPKFX MHQIM TURPS SKELV AUVQY SMICQ RFAHD YOZKD KXGJY KDYJM HCLSO CHWBP PUVUN LEONF OEYMO FBBMS OSNTV EBLFQ QKCXZ FDYOQ YBSIE HLUAR MNTQW LSMRT BQNAQ VPLOG EIZUH SYDYJ AQLAJ MGUHA NNTCF SSYBM AFJHM TRMQQ AQVQE FHBBZ BBJLN HQKNV XJXHJ VWAPA YVITU ZMXAG ZSPVF XGWQJ YZNTL OSPHP FTFLS EPLDB VQLUZ BORAJ LLOFE MYWUN DLFOG ELVKF ZYDSO HPHZQ YFABT ASDWL DLEDE 11400 021800 12. Eville s.n. (cachet: 3-2-1961): Smal a Loos BTWVE GHQMG DVIWW ZMDHA XBVMX SAFTM NUQJS ISVGN PJLCX INFIK JJIBP BXYOH XMWPW AMGBN IYWGH LSLNR BTWVE 11075 022200 Remarque: En 1961 ce message etait indechiffrable car la fausse cle (l'indicateur) etait incorrecte. La raison pour laquelle Loos n’est pas parvenu à lire ce message apparaît aussi clairement à présent. La valeur exacte de la fausse clé est: UEWVE au lieu de BTWVE. 14. Brazza 28B (cachet: 15-2-1961): Jacques a Nicolas [=Marliere] 11150 HSMEO TDUYB ZJQZI VVRHP ELHIL FXUKQ MNAFF ZPWSE DOXPX NFPPA RNMXS RZPUG LBZAI MXNFC ZZSHR XVTZI DZABT LPEET CNHFV RSNUF CJTQI HUKYM XZWBG HTLMO SWLOH EVJLF NOFYV ROSYC WXDTE WVEXE ACKPT HSMEO 11150 Texte clair sous forme de bandes PRINTEX collees sur le cryptogramme. CONTI NUEWI NTRIG UESWI NQUIE TANTE SWTAN TWLEO WQUWE VILLE WJACQ UESWB ISSEC TWVOU SWPRI EWVOU SWINF ORMER WDISC RETEM ENTWM ISSIO NWEXA CTEWC ONFIE EWHUB ERTWS TOPWI NTERE SSEYX References
|