HCM 5 rotors, genuine messages

• HCM 5 rotors home page
• HCM description
• Genuine messages (this page)
• Navy 1924 Challenge
• Poem
• Cryptanalyse
• Friedman's report
• Simulator
• Emulator in paper
• Challenges

Introduction

W. Friedman, in the document which describes his solution to the Navy Challenge, begins by describing Hebern's cipher machine and gives several examples of messages encrypted with the machine he has at his disposal. This machine is completely known to Friedman.

The configuration of the Army HCM

	Keyboard:  XAKHSZJLYWGPMIOURDBFTNVCQE
	Rotor 1:   GADBOCTKNUZXIWHFQYJVPMELSR
	Rotor 2:   IZNCTKUDPJEVOWLFHXSMGQAYBR
	Rotor 3:   PJXFWLTAUGYBMHROVNCKSEQIZD
	Rotor 4:   FLVARGWCMQBXNYIOTJUPSKEDHZ
	Rotor 5:   FQTGXANWCJOIVZPHYBDRKUSLEM
	Lampboard: TYOEUMXDFJQVKWBNSHCILRZAGP

The messages

• The rotors used are those described above and put in the machine in order (1,2,3,4,5).
• I was able to verify the encryptions and decryptions with my simulator of the HCM. This allowed me to validate the accuracy of my simulator.

1st message

Cryptogram:  PGR
Plain text:  ARE
Extern Key:  SIGNALS

H5_TOOLS> echo ARE | python hebern5_tui.py -E SIGNALS -D
...
Key:  SIGNALS
001: A ->XUCBLZ-> P    SIGNAMT
002: R ->DPKVKY-> G    SIGNANU
003: E ->SYNCVV-> R    SIGNAOV
PGR

2nd message

Cryptogram:  ONZOV HLDGN XBVPW YMRN
Plain text:  AMMUNITIONEXHAUSTED 
Extern key:  MEANING

H5_TOOLS> echo ONZOV HLDGN XBVPW YMRN |  ^
	python hebern5_tui.py -E MEANING -d -D
...
Key:  MEANING
001: O ->CNUAWX-> A    MEANIOH
002: N ->PJWOMM-> M    MEANIPI
003: Z ->WJWOMM-> M    MEANIQJ
004: O ->CLIDHT-> U    MEANIRK
005: V ->LAGTEI-> N    MEANISL
006: H ->RBJRZY-> I    MEANITM
007: L ->UQFHQF-> T    MEANIUN
008: D ->HNUAWY-> I    NFANIVO
009: G ->YZQHQO-> O    OFAOIWP
010: N ->PCNXRI-> N    OFAOIXQ
011: X ->GAGUGS-> E    OFAOIYR
012: B ->OHLKFC-> X    OFAOIZS
013: V ->LXSVLL-> H    OFAOIAT
014: P ->ZEABYX-> A    OFAOIBU
015: W ->NMKWNT-> U    OFAOICV
016: Y ->BVPLOB-> S    OFAOIDW
017: M ->FFEGUF-> T    OFAOIEX
018: R ->VAGUGS-> E    OFAOIFY
019: N ->PGHCDH-> D    OFAOIGZ
AMMUNITIONEXHAUSTED

3rd message

Cryptogram:  YONDS WMAUZ XFLQK GXVHR BTECJ P
Plain text:  AAAAAAAAAAAAAAAAAAAAAAAAAA 
Extern key:  NZAZAZN, Effective key: OAAAAAO

Encryption start details:
Key:  NZAZAZN
001: A ->XLVERB-> Y    OAAAAAO
002: A ->XLVERC-> O    OAAAABP
003: A ->XLVERP-> N    OAAAACQ
004: A ->XLVERH-> D    OAAAADR
005: A ->XLVERQ-> S    OAAAAES
006: A ->XLVERN-> W    OAAAAFT
007: A ->XLVERF-> M    OAAAAGU
...

4th message

Cryptogram:  IUOJU VJPFP JSCLV IKSDB MZDJS K
Plain text:  THEELEMENTSOFTHESCIENCEOFC 
Extern key:  NZAZAZN, Effective key: OAAAAAO

H5_TOOLS> echo IUOJU VJPFP JSCLV IKSDB MZDJS K | python hebern5_tui.py -d
THEELEMENTSOFTHESCIENCEOFC

References

• ANALYSIS OF A MECHANICO-ELECTRICAL CRYPTOGRAPH, PART I, TECHNICAL PAPER, BY WILLIAM F. FRIEDMAN Cryptanalyst, Chief of Signal Intelligence Section UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1934, Secret. (link)

  The messages presented are taken from this document.