I've read about britain's code breaking work with ultra and enigma and the advantages it gave to the western allies. Now i know America helped Russia with weapons, but did the benefits of British code breaking work also make it to and help in the Russian front? Did Britain intercept messages about eastern German troop movements and call up Russia to tell them where to expect attacks in advance? If not was it because Britain needed to keep this ability secret or because they simply couldn't intercept any messages from the eastern front?
The short answer is "not as much as it could have." And now for the incredibly long answer...
If you haven't already encountered it, Richard Aldrich's GCHQ is pretty much the definitive history of British SIGINT from the early days of the Government Code & Cypher School through to the role of GCHQ in the post-9/11 intelligence landscape.
Aldrich dedicates an entire chapter to the fraught intelligence-sharing relationship between British intelligence and its allies (but especially the USSR) during the Second World War.
But what you have to understand about ULTRA and similar large-scale SIGINT efforts (like the Venona project in the US) is that they are incredibly secret, even by the standards of intelligence work. Breaking your rivals' encrypted communications is a colossal intelligence coup, but it's one that has to be handled incredibly carefully — because if you tip them off to the fact that their secure communications aren't so secure, they're just going to change up and then you're back to square one. SIGINT sources of intelligence are usually kept within as small a circle as possible even within a country's government intelligence community, let alone internationally.
The important thing to note is that at no point in their alliance were Britain, the US and the Soviet Union not spying on each other. Their wartime alliance was one of strategic expediency, not of friendship. Stalin's extreme mistrust of the West, and the corresponding Anglo-American wariness of Stalin and communism meant that it was often a tense partnership.
The KGB and GRU (military intelligence) had some access to the Ultra work being done at Bletchley Park because they had at least two well-placed agents: John Cairncross, a civil servant and intelligence officer who worked at Bletchley Park for part of the war, and Anthony Blunt, an intelligence officer who was one of the MI5 liaison officers to GC&CS. Cairncross and Blunt were two of the Cambridge Five, probably the most successful spy ring ever operated by the Soviet Union — although, interestingly, neither knew that the other was also a Soviet agent.
Here's Aldrich on the debate over whether to share intelligence with the Soviet Union after the outbreak of war between the USSR and Germany in 1941:
Hitler's decision to turn east was a fabulous stroke of luck for Britain. [...] However, Bletchley Park now faced a new problem. Should it pass sensitive intelligence derived from Ultra to the new Soviet ally, which had been a dedicated enemy of Britain since 1917? The idea that two of Britain's adversaries were about to fight to the death filled most military intelligence officers with ill-disguised glee. Many argued that passing sigint to the Soviets was pointless, since few expected them to hold out later than 1942. Others insisted that not even Ultra could penetrate the fog of self-deception with which Stalin had surrounded himself.
In the event, Bletchley Park did develop a precarious sigint liaison with the Soviets. [...] They intended to send an officer from Bletchley [to Moscow], and in the long term even hoped to persuade the Soviets to accept a British Y unit, or forward listening station, that would intercept German tactical messages on their front. In late 1941 the Soviets agreed to a visit from Squadron Leader G.R. Scott-Farnie, who worked on Britain's Y interception system in the Middle East.
Scott Farnie gave the Soviets a good deal of information on low-grade German Air Force systems, but quickly came up against a different culture of intelligence exchange. The Soviets adored captured documents, and did not attach much credence to any information that was not supported by such evidence.
And here's Aldrich's account of British attempts to warn the Soviets of how insecure their own communications were:
The main worry about giving Ultra to the Soviets was the insecurity of their own cyphers — in 1942, Bletchley Park was increasingly aware of the German ability to read a great deal of Soviet operational military traffic in the field. Frederick Winterbotham, who worked on sigint distribution, argued that Moscow simply had to be told about the weak security of its cyphers. However, Winterbotham's colleagues insisted that it was 'impossible' to tell the Soviets, even though he had 'invented a good cover story' to explain how they knew. [...]
[...]
On 16 June 1942, Nigel de Grey, the Deputy Director at Bletchley Park stepped in and settled the argument. He noted that Edward Crankshaw, the GC&CS liaison with the Soviets, would soon be returning to Moscow for another visit. He would be ordered to give the Soviets the details of their compromised cyphers and 'the methods of reading'. [...]
In August 1942, Crankshaw briefed the Soviets on their appalling lack of security, typified by their alarming tendency to use low-grade cyphers for high-grade secrets. There was abundant evidence of this in German Air Force Enigma, but Crankshaw only hinted at it by 'somewhat tenuous means'. Predictably, the Soviets would not accept his warnings because 'direct evidence was not forthcoming'. Depressed, he went back to Bletchley Park in February 1943, never to return to Moscwo.
So the Soviets were offered intelligence, but frequently failed to acknowledge its validity or exploit it — just as MI6 and their own agents had been ignored when they warned that Germany intended to invade Russia in the spring of 1941. This is partly due to Soviet intelligence culture, and the pervasive mistrust of Britain (which was still more commonly viewed as an enemy than an ally), but it's also related to the broader culture of paranoia and delusion that characterised Stalin-era Russia.
In terms of broader reading in this area: Britain currently has several of the world's leading intelligence historians, so there's been a lot of excellent scholarship on British and Soviet intelligence history published in the last twenty or so years. In the texts below, you'll find a huge amount of information on the intelligence war before and during the Second World War, and then throughout the Cold War.
As well as the Aldrich history of GCHQ, there are also recently-published official histories of the other two British intelligence services, written by professional historians who were given unprecedented access to the services' archives:
On the Soviet side, Andrew has written several important histories of the KGB, working with two of the most senior Soviet intelligence officers to defect to the west — Oleg Gordievsky and Vasili Mitrokhin. They're excellent reads, and incredibly informative on the history, practice and thinking behind Soviet intelligence during the Cold War: