Thursday, April 21, 2022

Sigint Liaison with the Russians

After the German invasion of Russia in June 1941 a military mission (No 30 UK Military Mission) was sent to Moscow and learned that the Russians had a Y Service. In August, 1941 a Y officer from the Middle East went to Moscow. He was given little information, and wasn't allowed to see anything of the Soviet organisation. However, as British relations with the USSR had been bad for many years this was considered unsurprising, and in October 1941 the War Office on its own initiative attached an Army officer (who had been working as a Sigint traffic analyst) in 30 Mission. At the same time the Admiralty negotiated permission to build a Naval Y Station in the far north aimed at providing early warning of any attack on the convoys planned to bring supplies to the Russians. On the Army and Air Force side it was hoped principally to obtain Russian-intercepted German traffic and some help if possible on Japanese systems. In fact, apart from the supposition that Russian Sigint would be less efficient than British there wasn't any clear policy, other than that allied intelligence liaison was a "good thing". 

The Admiralty received Soviet permission to erect a Y Station at Polyarnii, near Murmansk, and British permission to give the Soviets information about Auka (a low-grade Luftwaffe system), and, in May 1942, sent a naval officer from GC&CS to Murmansk to arrange for the exchange of Naval and TA intelligence. As a result of this some naval intercepted traffic reached GC&CS and there was also an interchange of DF bearings.

The War Office representative also made some progress. He was authorised in February 1942 to train the Russians to break the German police ciphers which were being used in rear areas on the Russian front, as well as showing them some traffic intercepted in the UK. (It was never the intention that British success against Enigma should be revealed.) He reported that this had produced a favourable reaction and he asked to be allowed to expand the exchange, giving the Russians identities recovered from callsign analysis of certain German stations in return for traffic intercepted in Russia. In June 1942 he was recalled for discussion of policy and went back to Moscow as representative, not of the War Office, but of the Y Board. But the mood in Moscow had changed: the Russians stalled and eventually in November the Head of the Soviet Army section dealing with Traffic Analysis suggested that cooperation should be discontinued.

Naval cooperation in the far north continued on a restricted basis, though some intercepted material inaudible elsewhere did reach the UK. This lasted until spring 1943 when, just as the UK staff were preparing to hand over another batch of Y material, the Russians suddenly entered the British site, sealed up the transmitters and took away the "meaconing" apparatus (a means of falsifying German Beacon transmissions.) At the same time it came to British knowledge that the German Y Service was reading some high echelon Russian cipher systems without much difficulty. Convoys were not actually in operation at this time, but were expected to resume and the closure of the station and Soviet insecurity greatly increased the hazards of running them.

In return for German Police material, the UK had given the Soviet military the Japanese Military Attaché code, the "Bird book" and index (the GC&CS process for breaking out German enciphered callsigns), the solution to German aerodrome serviceability reports, the process for recovering German police keys, Auka, and some ISOS keys. The Russians had also been made aware that the UK could read the Army tank code, Army medium grade field ciphers as well as the cipher used by one of the German sabotage units. The UK side decided that unless and until the Russians resumed cooperation, no further material should be sent. There was no point in keeping a representative in Moscow and the liaison officer, while retaining the title 'Russian Liaison Officer', was relocated to GC&CS. GC&CS had only one vote on the Y Board but it was a significant one. its attitude towards Russian cooperation was becoming more assertive and more reluctant. 'Jumbo' Travis wrote to Heads of Sections in May 1943 saying that he was prepared to consider an exchange, but only if there was a solid return "as I am not now a believer in Russian cooperation".

Although it had been decided that the Y Board should have no representative in Moscow, 'C' felt that an SIS liaison officer might usefully represent Sigint as well. One went to Moscow in the summer of 1943, just in time for several things to happen all at once. The Soviets asked for a full description of the German Enigma machine; they captured a copy of Auka themselves; and German Y Service traffic intercepted by the UK revealed that Russian ciphers were still being read by the Germans.

A meeting took place in summer 1943 after the British Ambassador made representations to Molotov, and it became clear that the Soviets' main interest was to find out what exactly what the British evidence of Russian cipher insecurity was. They were told that the information had come from a disaffected Austrian prisoner of war and from information from Japanese Military Attaché decrypts; they were also told that the UK side would give no further Sigint-derived information until the Russians delivered on their promises of the previous year. There were a few sporadic meetings and it became perfectly clear in spite of the SIS representative's attempts to put the best possible interpretation on what was going on, that the Russians were trying to get what they could from the British without giving anything away themselves. Telegrams continued to pass desultorily throughout 1944 and an Enigma machine and a small amount of very low level Y information was sent, though probably more for SIS's benefit than for Sigint's. Before the end of the war cooperation had ceased.

Why were the Soviets so reluctant to carry out an exchange of material? GCHQ believed post-war that the Soviet Sigint organisation had made the authorities in Moscow aware that the material being offered by the UK was low grade and that therefore either the UK was keeping its aces up its sleeve, or it didn’t have any capability worth wasting Soviet time on.

In my last post I told the story of how some information derived from Enigma decrypts had been published after having been passed by military censors. Commenting on Twitter @jock_bruce said that "in that story the point is that the folk clearing stuff for publication need to know what they’re actually protecting". I think that there is a similar issue here: those making decisions – the single services, and subsequently the Y Board – didn't understand that any half-way competent Sigint organisation would realise that valuable information was being withheld.

Sigint liaison worked with the French and the Poles when there was a full exchange of knowledge between the national Sigint organisations of each country, and subsequently worked with the US and Australia, Canada and New Zealand, because there was full sharing and integration of staff in each other's organisations. It couldn't work if the exchange was partial and low-level, and it certainly wouldn't work if non-Sigint personnel were representing Sigint.

 

Monday, April 11, 2022

Locking a Stable Door

There is an interesting story in Guy Liddell's diaries (The National Archives (TNA) KV 4/187 and 4/189) about publication of Sigint secrets in a book published in 1941.

March 8th (1941)

SIS are in a great state about the publication of a book called The Diary of a Staff Officer, who (sic) in addition to criticising the French and British Commands in rather an outspoken manner makes reference to work affecting the GC&CS. I communicated first with Mr Ray of Methuens, the publishers, and then with Dick's brother who is a partner in the firm. 1,900 copies have already been issued and since further demands are being made by the booksellers, most of them must be in the hands of private individuals. Meanwhile, another 7,000 copies are in preparation and are to go out on Tuesday next. Dick's brother tells me that the book was submitted to the MOI and passed by all 3 service representatives before Xmas. It was then published serially in the USA. It is possible however that the offending passages may have been omitted. A few copies have gone to Canada and the book has been extensively reviewed here in the Press. I am suggesting that the 7,000 copies should not be circulated and that the censorship and D.4 should be warned against letting any of them out of the country. I feel that if we do more than this we shall only be drawing attention to what we are anxious to donceal (sic). We shall be in a better position to decide on Monday.

March 10th (1941)

I saw Stewart and Hopkinson about the officer's diary. We discussed the problem in all its aspects and thought that before coming to a definite conclusion it would be wise to see Gribble at the earliest possible moment.

March 11th (1941)

Stewart, Lennox and I saw Gribble at the WO. He admitted that he knew the messages came from a very secret source but he thought he was amply covered by having submitted his diary for censorship. He admitted however that he had shown the document previously to his agent to see whether its contents were like (sic) to interest the public if they were published in book form. It was explained to him that certain passages constituted a grave indiscretion and that it was in the public interest that he should cooperate with us in doing anything possible to pick up the pieces. We eventually agreed that even though the offending passages had appeared in the Saturday Evening Post it would be better to issue the new edition in amended form. Gribble was to tell his agent that he wished to make certain amendments in the text and therefore that he would like the return of the proof copy from America before any further action is taken. As regards the Manchester Evening News who were asking permission to publish the book in serial form, it was decided to see first whether they were proposing by their own selection to exclude the offending passages. If not, we should have to say that the book could not be published serially until certain amendments had been made which the author considered desirable in the light of subsequent information received.

In the afternoon Dick's brother came down and we discussed details about Gribble's book. It was apparent that if the offending passages were taken out it would be quite clear that a new one had been gummed in. We therefore decided to buy up the whole of the second edition which was already bound and have arranged that the offending page in the other two editions should be removed altogether, with those which were joined to it. These would be collected before the new amended pages were delivered to the printer.

2nd February (1942)

According to an intercepted letter a New York publisher is trying to arrange with Watt, London, for the publication of Major Gribble's book Diary of a Staff Officer in German. It is to be printed in Switzerland. Lennox has got hold of Gribble and will tell him to stop the publication. If the book circulates in Germany there is a possibility that what has been overlooked may come to light.

(Key to people: Dick is Dick White, MI5 officer and future DG; Stewart is Stewart Menzies, 'C'; Hopkinson is probably Henry Hopkinson, PS to PUS FCO (subsequently Lord Colyton); Lennox is Gilbert Lennox, MI5 officer and responsible for MI5 liaison with the War Office.)

Fascinated by this story, I managed to locate and buy a copy of the first (offending) edition of this book. (The second edition was, presumably, bought up and destroyed; and there were at least third and fourth editions according to abebooks.)

The offending passages appear to be two of the entries for 12 June 1940. Here is the entry for the whole of the day.

June 12th. 1130 hours. The German have three fresh army corps South of RHEIMS. This town was occupied yesterday when the French made a complete withdrawal to the MARNE. There are now 80 German divisions on the CHANNEL – MONTMEDY front. The French possess some very exhausted 35 divisions. There is no longer any hope of success for the French.

PS (private sources) is providing a fund of information. There were 45 messages last night.

1200 hours. The last of these messages consisted of a single word: "SEDAN". This is the German word for bombing PARIS.

1210 hours. It was repeated to us again today that the lack of enthusiasm in the French armies could be attributed to the fact that one third of them was drawn from the occupied territory. Even more, it is thought that at least half the soldiers in the French army have now lost their homes through German occupation.

2300 hours. Very unpleasant news tonight. A big break through over the SEINE with enemy reported as far over as DREUX and EVREUX. Looks like the next move towards the SEINE.

It is pretty clear that Major Gribble was trying it on. He knew how sensitive the material originated from Sigint was, and he knew that the volume of reportable intercepted messages was significant. But he guessed that the military censors wouldn't know as much as he did. I imagine that the fact that "SEDAN" was identified as a codeword message (CWM) meaning "Bomb Paris" was what caused the stir when the book was published, but it's hard to believe that the Germans hadn't assumed that the CWM would be compromised as soon as Paris was bombed.

This diary entry was written before the most severe levels of security were designed for the protection of Sigint, and it is in part because of what happened in France that things were tightened up. As de Grey says, in Appendix III of his Organisation and Evolution of British Sigint (TNA HW 43/78):

The policy adopted in regard to the Enigma decrypts had no repercussions during the "Sitzkrieg" [the Phony War] – they were dull and of no immediate operational value. It was not until the Battle of Norway that the intelligence became of such operational value that its dissemination in a wider field became a problem. Norway was over before any organisation could be set on foot. The Battle of France supervened but it was not until May 22nd that the current German Air Force key was solved and thenceforward solved regularly – that is until a week or two before the end of the Battle. The arrangements to supply GQG [Grand Quartier General: the French GHQ] with results were untried and neither Ally was versed in the exchange of such material. GHQ and AHQ had not had the experience of receiving a flood of such material, were in no position to interpret its significance and were in ignorance of its reliability. The whole front was crumbling and although it is possible that some of the information reached the higher commands it is doubtful whether it was of any use. The War Office channels of dissemination were abandoned possibly for fear of their insecurity and SIS WT was substituted in the last few days. The difficulties of secure dissemination to the commands in the field were thus fully brought to light.

The diary entry illustrates de Grey's point: as well as copious and detailed predictive intelligence from intercepts, Gribble's office was handling top level information about German and French Orbat and German movements, as well as engaging in dubious analysis of what might or might not be demotivating the French Army. This isn't a picture of a well-functioning Intelligence Staff: those involved had no training in or experience of what they were supposed to be doing.

The solution chosen to solve the Sigint part of this problem was ULTRA and the special handling procedures associated with it were effective in protecting the fact of successful cryptanalysis and the products which that success brought, but at a cost: not everybody who handled intelligence had access to all relevant intelligence on a given subject. The level of clearance needed to have access to the most sensitive intelligence was granted to only a small proportion of members of intelligence staffs. That in turn produced problems of its own.