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A Cryptanalysis Service During the Spanish Civil War

2012; Taylor & Francis; Volume: 36; Issue: 3 Linguagem: Inglês

10.1080/01611194.2012.687428

1558-1586

José Ramón Soler Fuensanta, Francisco Javier López-Brea Espiau, Diego Navarro Bonilla,

Cryptographic Implementations and Security

Abstract This article gives a brief study of the Zaragoza Cryptanalysis Service during the Spanish Civil War (1936–1939) based on the notes and letters from one of the finest cryptologists of the Spanish Civil War. Keywords: cryptanalysisJosé Maria IñiguezSpainSpanish Civil War Acknowledgements We wish to express our sincere gratitude to the Iñiguez family and the Sarmiento family for their help and for all of the information they provided. We would especially like to thank Blanca Gerona Iñiguez, for her willingness to help, her comments, and transcriptions of her uncle's documents, as well as the brothers Angel, deceased a few months ago, and Álvaro Sarmiento Farinós, all of whom have given us invaluable help and offered frequent expressions of support for our work. Notes 1The Mallorca group owes part of its fame to the excellent work of Baltasar Nicolau Bordoy (19 January 1903 to 1 August 1963), another great cryptanalyst of the time. Apparently, he did not have any connection with cryptanalysis before the war. However, during the war, he broke 26 codes and 144 ciphers, combining this aspect with the tactical direction in the use of wireless interception services in the transmissions company from the general staff and the Mediterranean blocking forces. After the war, he continued his work in decryption in Palma de Mallorca. Until his death, he combined decryption tasks with the teaching of cryptography and cryptanalysis to army officers. Those who knew him at work speak of him with admiration and considered him an extremely intuitive cryptanalyst. 2Spanish cryptanalysts working for the French in World War II in the PC Cadix and Bruno. 3The first document that we have regarding José María Iñiguez's cryptanalysis duties is from 2 March 1937. 4Acción Ciudadana was an armed militia organized by supporters of the new regime that emerged from the military uprising. They acted as a paramilitary force in support of the military forces in the rearguard, carrying out surveillance, public order, and political repression activities. 5The Military Government was the military institution in charge of the civil and military administration in war times. 6In courses offered by the General Staff after the war, besides the typical notes, the book Éléments de Cryptographie by Captain Roger Baudouin [Citation3] was used as a basic reference. Evidently, this book cannot have been used during the war, since it was not published until 1939. It is thus more likely that one of the following books was used: Cours de Cryptographie by General Givierge [Citation5], of which we have a copy with the stamp of the SSE (Special Service Section); Traité de Cryptographie by Lange Soudart [Citation7] with the same stamp, and which has the following inscription on the first page “for the Special Service Section of the Balearic Islands,” probably in reference to the Mallorca decryption group; or General Sacco's book, Manuale di Crittografia [Citation13], which has the name of its owner, Enrique Puig, written on it; thanks to his signature, we were able to verify that this refers to Enrique Puig Guardiola, head of the Information Service of Palma de Mallorca during the war. All three belonged to the same person, who sold them to a used bookstore, where they were finally acquired by one of the authors. 7We only recall two texts of this same style, both from the 16th century [Citation16]. 8This order was possibly obtained through experience with military decryptions, as it does not coincide with those given by Givierge [Citation5]: EAONSIRLDCTUPMGBYVFJQZHXÑKW, Lange and Soudart: EAOSIRNLDTCUPMQBYGHFVZJX, or Sacco: EAOSIRNLDCTUPMQYBGHFVZJXKW. 9The machine used by VCE was the K-291 [Citation20]. 10Besides the mentioned centers of Palma de Mallorca, Zaragoza, Cádiz (under the navy), and Burgos, there was one in Irún, under the SIFNE, the Information Service headed by the Catalonian lawyer José Bertrán y Musitu, which operated in the south of France and in the area near the border with that country. As for foreign groups, there were specialists in Spain from the Ufficio D'italiano assigned to the Italian expeditionary corps, the CTV, and Germans from the Condor Legion known as the “Grupo Wolm,” although it seems that, strictly speaking, they worked more on wireless interception than on decryption. 11Juan Solabre Lazcano, a telegrapher at that time, joined the rebellion in its first stages, coming under General Mola's service in August of 1936. His initial assignment was enciphering, deciphering, and the transmission of telegrams. In March 1937, he was called up to Burgos by the Nationalist Information Service, the SIM (the Military Information Service), which was renamed the SIPM (Information and Military Police Service), in November of that year in order to avoid confusion with its Republican counterpart of the same name; there he was put in charge of the ciphering of messages from Franco's headquarters and the Information Service. In May, the decryption services of Burgos, Zaragoza, and Palma de Mallorca were merged together, and he began to work in the decryption department, taking charge of the coordination of said services under the orders of Commander Major Antonio Sarmiento León-Troyano. Although he mainly worked on tasks related to administration and coordination, he began to stand out in the area of decryption, breaking 24 ciphers during the war, half of those broken by the Burgos group. The war was over and he was already working for the decryption (4°) department of the Information Section (3ª) of the General Staff when his popularity as a codebreaker reached its peak. Patient and calm, he was a great expert in breaking diplomatic codes. During his 25 years of service at the General Staff, he broke some 30 of them from approximately 20 countries, including the Vatican and Great Britain. 12Guardia Civil is the police, under the military regime, that acts outside the cities. 13The Transmission Battalion in Mallorca was in charge of the interception of Republican radio communications in Mallorca. 14The order is from 30 December 1938 [Citation6]. 15Letter from Iñiguez to the SIM Central Office in Burgos dated 5 June 1937. 16Letter from Sarmiento to Iñiguez dated 5 April 1938. 17Letter from Iñiguez to the SIM Central Office in Burgos dated 5 June 1937. 18Letter from Iñiguez to the SIM Central Office in Burgos dated 8 July 1937. “I'm not using a code in this letter because I think it is an unnecessary precaution. I will use a double envelope to avoid any misappropriation. Anyway, if another procedure should be used, I trust you will tell me. Consult with the bosses about this.” We do not know the response from the central office in Burgos, as it does not appear in any of the later letters. 19For a description of the strip cipher system, see [Citation19]. 20In the original Diplomática de Diccionarios. 21This sentence can be translated as “the rest of our intellectual reserves.” 22Letter from the SIPM Head Office to José María Iñiguez dated 2 March 1937. 23This code was broken at the same time, and independently, by the Zaragoza group and the Palma de Mallorca group, which is the one that generally receives credit for the reconstruction of this cipher [Citation19]. 24Letter from Iñiguez to the SIM Central Office in Burgos dated 9 June 1937; see Appendix II. 25Letter from Iñiguez to Juan Solabre in the SIM Central Office in Burgos dated 27 June 1937. 26During the Spanish Civil War, the usual way to name a cipher was to use the term “key.” In this text, we will use the name cipher. 27Letter from Iñiguez to the SIM Central Office in Burgos dated 8 July 1937: “If you can shed some light on the work, I would like it if you could tell me about it, as I feel disoriented and I cannot hide the fact that I am somewhat discouraged, because I do not clearly see a way to work on this new project that might be fruitful.” 28Letter from Iñiguez to the SIM Central Office in Burgos dated 8 July 1937: “I have requested bibliography to orient me, as what I have on hand is very bad. If you know of a good book that is not in English (for me the best would be German) you could tell me and I would work on it.” The preference for German as a language to study was typical of 1930s Spain, where Germany was considered advanced in the areas of engineering, medicine, and science in general. Top students from Spanish universities frequently did graduate degrees in Germany. 29Letter from Iñiguez to the SIM Central Office in Burgos dated 23 July 1937. 32BABY AND ME GOOD. DISTURBED WITH HAPPENED DAY 2. ANSWER PROMPTLY IF SOMETHING HAPPENS. HUGS. ANITA. 30Letter from Solabre in the SIM Central Office in Burgos to Iñiguez dated 24 July 1937, in which he sends him the SERVICIO N°. 3 CIPHER, the KOMSOMOL (6 tables) and the first MOURO table, indicating that he has already gotten 3 and that Mallorca has sent him another 3. 31Letter from Iñiguez to Solabre in the SIM Central Office in Burgos dated 24 July 1937. 33ANITA LOPEZ TEATRO 14 LOS DOLORES. - I'M GOOT NOTHING HAPPENNED HUGES. ANDRES. 34In this case, the error was the individual. The MOURO code changed letters for two or three numbers. The real text was ANDRES QUESADA DESTRUCTOR JOSE LUIS DIEZ; letter from Iñiguez to Solabre in the SIM Central Office in Burgos dated 24 July 1937. 35This cipher is a strip cipher; see Appendix III. 36Letter from Iñiguez to Solabre in SIM Central Office in Burgos dated 10 August 1937. 37Letter from Iñiguez to Solabre in the SIM Central Office in Burgos dated 28 August 1937. 38We have as yet been unable to discover the identity of this colonel. It is highly likely that this is a pseudonym (Recke would be warrior or hero in German); the use of a false name was very frequent among German specialists. 39All the Republican communication rings have an identifier formed by two to four letters. The indicative TS was probably “Service Transmissions.” 40Colonel José Ungría was the head of the Nationalist Information Services. 42Letter from Solabre to Iñiguez dated 18 November 1937. 41The EEQ stations were probably the DEDIDE stations. 43For example, we have the note from 5 January 1938 to the Air Force Headquarters in Levante: “I ask that the following points be clarified with the greatest precision possible: 1. Yesterday, 4th of January, at 14:25 9 airplanes flew from Monte Javalón towards a point which may be Teruel or some place in that sector that is visible from Javalón. What kind of airplanes were there? Could you specify if they were going from Javalón to Teruel or returning or what route were they using? They must have been rapid bomber planes.2. The same day at 14:42, did airplanes fly over Muletón at 300 meters altitude? If they did not fly over that point, where did they fly? What kind of planes were they?3. That same day, at 15:30 there were 10 airplanes over some point which it would be good to know if it was Teruel or what point it was. The information comes from the Monte Javalón observatory. What kind of planes were they? Were they circling that point, or were they firing machine guns or bombing? 44Aviation's SUR code, formed by ten tables, was the code that substituted the NORTE code, which had been active since mid-November of 1937. We have no reference as to whether the NORTE code was decrypted or not. 45Letter from Sarmiento to Iñiguez dated 11 May 1938: “I haven't forgotten about the organization in Zaragoza and, in this regard, that Region's Command, will be informed, from here, of whatever it may need. I would be very grateful for an estimate of needs to that end.” 46“Lieutenant Colonel Dragone has told me that Mr. Espinosa and Mr. Vuolo, of his group, have contacted you”; letter from Sarmiento to Iñiguez dated 26 March 1938. “If you have to give up on the study of the cipher, there is a Second Lieutenant, Erice, who is with the Italians in Fraga and who does not have a lot of work and is in good terms with diplomatic circles (cryptanalysis)”; letter from Martínez de Velasco to Iñiguez dated 28 December 1938. 47Letter from Sarmiento to Iñiguez dated 5 April 1938. 48Letter from Dragone to Iñiguez dated 13 May 1938 and note from 15 May from Deimpelmann. 49Letter from Dragone to Iñiguez dated 13 May 1938: “I will continue with this study, which as you can infer seems extremely difficult and almost impossible to bring to a successful conclusion.” 50Letter from Sarmiento to Iñiguez dated 26 May 1938: “We have received your studies of the “aviación, cipher” which will be distributed today to the following groups: Wolm, Dragone, SIPM, and sent to Palma de Mallorca.” 51Transcription from José María Iñiguez's memoirs by his niece, Blanca Gerona Iñiguez. 52Letter from Sarmiento to Iñiguez dated 26 July 1939. 53Román Martínez de Velasco was born on 26 June 1905. When he became a captain engineer, he was appointed attaché to General Franco's headquarters in the wireless interception and decryption service on 15 August 1938. Apparently, his work as a codebreaker was good. He was voluntarily discharged shortly after the war ended [Citation20]. 54José Centaño de la Paz was the head of the Fifth Column's largest group in Madrid, the so-called “Lucero Verde,” which played an important role in the negotiations with Lieutenant Colonel Segismundo Casado for the surrender of the Republican army and the end of the war. 55He is, without doubt, Juan Solabre Lazcano. 56José María Iñiguez. 57SIFNE was officially placed under SIPM on 1 March 1938. 23 or 45: Semáforo punta Galea (traffic light). 53, 36, 29, or 96: Ministro Marina (Navy Minister). 63, 64, and 67: Fin novedad por estas costas (end of news along these coasts). 58The original can be seen in the General Military Archive of Ávila (Catalogue Number C.2218, Cp. 2, D. 5).