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Code Warriors

Page 25

by Stephen Budiansky


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  Frank Rowlett was never a member of the Ralph Canine fan club. Always contemptuous of those less knowledgeable about cryptology who tried to tell him how to do his work, Rowlett was irked from the start by the new director’s “hip-shooting” management style, in the words of a declassified NSA history. When Canine in 1952 abruptly directed his top civilian cryptologists to swap positions as part of his pet rotation scheme, ordering Rowlett to become head of communications security and giving up to Abe Sinkov his plum assignment as head of production, Rowlett left in a huff and took a job at CIA. Many of his old colleagues viewed him as a “traitor” for going over to the rival agency, which aside from all of the other sources of tension was even setting up its own small signals intelligence unit to try to chip away at NSA’s monopoly in the field. Getting an old hand like Rowlett was a coup for CIA. He was soon head of its clandestine electronic surveillance section, Foreign Intelligence/Staff D.15

  Rowlett did not think much, either, of all of the outside panels and committees brought in to review the stalled progress on breaking high-level Soviet code systems. When CIA was sent the findings of the Clark committee for review and concurrence, he filed a dismissive rejoinder that began, “This report is dangerous.” Rowlett witheringly observed that it had been prepared by “individuals who…have no experience or background in the field” of signals intelligence. “Truisms and cliches are profuse throughout the discussions and from them specious conclusions are drawn. Nowhere does the report get down to brass tacks and examine step by step either professionally or expertly the essential elements of COMINT production.” There may have been little love lost between Rowlett and his old agency, but he sarcastically pointed out that NSA’s director surely did not need a committee to remind him what “everybody in Washington knows”: that “as far as cryptanalysis is concerned there is a desperate need for the production” of decrypted high-level Soviet traffic. He suggested in effect that all of the outside “experts” shut up and let NSA get on with the job, which only it knew best how to do. “Most of the people on these panels would not have known a Russian cipher if it hit him on the head,” he later said. “Rule by committee is a terrible way to run a spy agency.”16

  The truth of the matter, however, was that it was Rowlett’s own growing doubts over NSA’s failure to make cryptanalytic progress against the Russian codes that in part led him to make the move to CIA. The shift of Soviet communications from HF airwaves to landlines and line-of-sight UHF and the increasing sophistication of Soviet cryptography helped persuade him that the future of communications intelligence lay more in cloak and dagger than pencil and paper. In 1951, Rowlett confided to Bill Harvey, who had founded CIA’s Staff D, his frustrations at the loss of intelligence as a result of the unreadability of Soviet signals. Shortly thereafter, a young civil engineer from the agency’s Office of Communications was summoned to a meeting where Rowlett and some officials from the Office of Plans were present. “The only question they asked was whether a tunnel could be dug in secret,” the engineer recalled. “My reply was that one could dig a tunnel anywhere, but to build one in secret would depend on its size, take more time, and cost more money.”17

  In December 1952, Harvey arrived to take charge of CIA’s Berlin Operations Base with his and Rowlett’s plan to make a bold end run around the Soviets’ cryptographic security already well under way. Berlin was the hub for telephone circuits running throughout Eastern Europe. With assistance from the British SIS, which had run a similar tunneling operation in Vienna, Operation Regal aimed to beat the Russians at their own game, tapping directly into cables that carried long-distance telephone calls and teleprinter traffic of Soviet military and civilian officials between Moscow and East Germany and other Soviet satellites.18

  Harvey was far from the obvious man to run the operation. A former FBI agent who joined CIA at its start in 1947, he bristled at the Ivy League types who filled the agency, a distinct contrast from the blue-collar atmosphere of the FBI. His physical appearance announced that he was definitely not a member of the polished East Coast elite: he was short, fat, with a bullet head and a smudgy mustache. His agents called him “the Pear.” He kept a large collection of pistols he was always toying with, and took special satisfaction in belligerently parading his mid-western uncouthness before the “nice Yale boys,” as he sneeringly called them, salting his conversation with crude observations deliberately intended to discomfit his more refined colleagues.

  In Berlin—and now separated from his first wife, whose honor he had defended with a drunken punch at Guy Burgess at Kim Philby’s home the year before—Harvey took up residence in a huge, stuccoed mansion with a garden and swimming pool in the American Sector where he hosted alcoholic lunches for the other CIA officers; guests arrived at noon and were served pitcher upon pitcher of martinis until four o’clock, when some food finally appeared. “Trial by firewater,” his staff called it. Harvey was more than just a heavy drinker; he would in his declining years suffer the ravages of advanced alcoholism. But there was a fierce intellect under that crude exterior. Harvey had graduated from high school at age fifteen and had earned a law degree from Indiana University; his FBI background check reported that he had been considered “brilliant” by his teachers. He was also a thoroughgoing, street-smart case officer who left nothing to chance.19

  In January 1953, having recruited several agents inside East Berlin’s telephone exchange, the Berlin Operations Base arranged a clandestine sampling of the long-distance cables that its sources had identified as assigned for official use. Late one night, a telephone operator in the main exchange of the East Berlin Post Office surreptitiously patched a connection from a prime target circuit to a line connected to the West Berlin exchange for fifteen minutes; a CIA technician posing as a West German employee of the office was there to record the take.

  Over the next six months the sampling continued, usually just a few minutes at a time whenever the operator felt she could safely elude detection. CIA officers never knew ahead of time when that would be and had to maintain a twenty-four-hour watch at the West Berlin Post Office site. By August they had two hours’ worth of material, enough to make a persuasive case that a considerable amount of valuable intelligence was to be gleaned from the unguarded telephone conversations passing over official channels.20 Rowlett made a final visit to Berlin to prepare a formal proposal to the CIA director for their audacious plan to bore a tunnel under the border to tap directly into the East Berlin cables; Allen Dulles’s approval came in January 1954. Construction began the following month.21

  From a tradecraft standpoint the operation was a technical tour de force. Specially designed tunneling equipment was tested on a 150-foot-long mockup in New Mexico; 125 tons of steel liner were transported on freight trains crossing the East Zone to West Berlin, packed in double-crated boxes as a safeguard against accidental exposure; an entire two-story warehouse was built at the site next to the border chosen for the tunnel’s terminus to house receiving equipment and, in its basement, conceal the thirty-one hundred tons of earth removed in excavating the 1,476-foot-long bore over the course of a year; air-conditioning ductwork, later hastily supplemented by a separate line of cold-water chiller tubes when tests proved the first system inadequate, kept the tap chamber cooled so that heat from its vacuum-tube-filled preamps would not create a telltale ring of melted ice on the East Berlin roadway above in winter. From May to August 1955 technicians completed the delicate task of making the actual connections to the three targeted cables. On average 121 voice circuits and 28 telegraphic circuits were in use at any given time. All were collected on what would become a staggering pile of fifty thousand reels of magnetic tape during the time the tap remained in operation. The voice recordings, containing sixty-seven thousand hours of Russian and German conversations, were sent to London for transcribing by a special section staffed by 317 Russian émigrés and German linguists; the teleprinter signals, many of them multiplexed, were also collected o
n magnetic tape and forwarded to Rowlett’s Staff D for processing.22

  The operation was a brilliant technical success; it also threatened to bring the bureaucratic infighting of the U.S. intelligence services to the breaking point. CIA had not bothered even to inform NSA officials about the tunnel’s existence until a month after the first tap went into operation, and even then refused to discuss technical details or allow more than a small number of specially cleared senior NSA analysts access to the material. Now it was CIA’s turn to refuse to share credit, and at a time when precious little else was available about Soviet military organization and activities the tunnel taps provided current intelligence “of a kind and quality which had not been available since 1948,” a CIA report boasted.

  Among other things, the intercepts revealed the location of a hundred Soviet air force installations in Russia, East Germany, and Poland; the names of several thousand high Soviet military officers; the identification of several hundred scientists involved in the Soviet atomic program; a doubling of Soviet bomber strength in Poland and the equipping of the Soviet air army in East Germany with nuclear-capable bombers and twin-jet fighters with airborne intercept radars; and the order of battle for ground force units in the Soviet Union “not previously identified or not located for several years by any other source.”23

  The triumph would prove short-lived. At one of the joint CIA-SIS planning meetings for Operation Regal, held in London on December 15–18, 1953, the British representatives included George Blake, a Dutch-born SIS officer who had just been released from three years’ captivity in a North Korean prison. Blake had been a member of the anti-Nazi resistance in the Netherlands as a teenager, escaping to England in 1942 disguised as a monk. A gifted linguist, he was recruited by the British spy agency and later sent to the British embassy in Seoul, where he and the rest of the staff were cut off when the capital was overrun by North Korean troops in the opening days of the war. A month after the London planning meeting, at a carefully prepared rendezvous with a KGB officer atop a double-decker bus, Blake turned over a carbon copy of the meeting minutes.

  It was not until 1961, acting on evidence supplied by a Polish defector, that SIS discovered Blake had been a Soviet spy ever since returning from North Korea. On his third day of interrogation he suddenly blurted out a confession, provoked when one of the SIS interrogators mildly suggested that his actions were perfectly unstandable, as he had surely been tortured and brainwashed during his captivity in North Korea.

  “Nobody tortured me!” he shouted. “Nobody blackmailed me! I approached the Soviets and offered my services to them of my own accord.” He later said that it was the relentless bombing of North Korea by the U.S. Air Force that convinced him he “was on the wrong side.”24

  In 1966, Blake escaped from Wormwood Scrubs prison and made his way to East Germany and then to the Soviet Union, where he lived the rest of his life on a KGB pension, receiving the Order of Friendship from Vladimir Putin on his eighty-fifth birthday in 2007. In 2015, researchers examining the archives of the Stasi, the East German secret police, were able to establish what happened to six of an estimated four hundred Western agents whom Blake betrayed: five were held in Stasi prisons for up to seventeen years; one was taken to Moscow, most likely shot. The hundreds of others no doubt encountered like fates.25

  For decades it was not known why the Soviets had not acted earlier on the material Blake provided on the Berlin Tunnel; there was even speculation that the KGB engineered a massive deception operation, feeding disinformation to the listening CIA tappers. But information revealed by former KGB officers in the 1990s pointed to a more prosaic explanation. The KGB’s own high-level communications went on a separate system of overhead lines that could not be tapped without its being obvious, and, concerned above all with protecting Blake as a valuable source inside SIS and unwilling to share its secrets with rival agencies, the KGB had simply left both the GRU and the Stasi in the dark about the tunnel’s existence. Bureaucratic infighting and the red tape of security restrictions were hardly the sole province of the U.S. intelligence agencies. (As General Canine was fond of reminding NSA’s production staff in their moments of frustration, “Don’t forget, the Russians also have to put on their pants one leg at a time.”) And so for nearly a year insecure military communications continued to flow into the CIA tap while the KGB got around to inserting its second leg in its trousers. A small KGB team was formed to secretly locate the tap but did nothing further until a plan was ready to stage the tunnel’s discovery in a way that would not implicate Blake. Finally, on the night of April 21, 1956, a Soviet army signal company, ostensibly searching for the cause of a short circuit caused by recent heavy rains and flooding, began digging on the street directly over the tap chamber. The next day the Soviets and East Germans were triumphantly announcing their discovery of the “American spy tunnel.”26

  Plans for Operation Regal called for the United States to issue “a flat denial of any knowledge of the tunnel” if it was discovered: CIA thought the Soviets would rather join a tacit conspiracy of silence than admit that their communications had been successfully breached. But Khrushchev saw another chance to squeeze the Americans in their anatomically vulnerable spot and ordered an all-out propaganda offensive denouncing the “perfidy and treachery” of the United States for abusing its position in the German capital, and insinuating that the West sought to keep Berlin divided merely to exploit it as a base for such illegal provocations against the German Democratic Republic. The East German authorities offered tours of “the capitalist warmongers’ subterranean listening post” and provided a guestbook where visitors could express their “indignation.” Khrushchev’s only restriction on what should be revealed was that nothing should be mentioned about British involvement in the project: “Despite the fact that the tunnel contains English equipment,” the Soviet Foreign Ministry instructed its ambassador in Berlin, “direct all accusations in the press against the Americans only.” The Soviet leader was at that very moment on his visit to England and did not want any diplomatic boats rocked.27

  With the secret in the open, CIA likewise concluded that Operation Regal was now more valuable as a public relations weapon and quietly leaked impressive facts and figures underscoring the technical ingenuity and logistic challenges of the $6.7 million project—and probably coming off the better by at least giving Americans and West Germans a sense of pride that, as a report from the NBC radio correspondent in Berlin put it, “We pulled off an espionage trick on the Reds for a change.”28

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  The teleprinter traffic from the tunnel taps included both plaintext and enciphered signals, and Rowlett had hoped that even some of the otherwise indecipherable material might be readable owing to stray emissions that teleprinter devices were known to give off: these ghost signals could in theory be carried along the metallic twisted-pair telephone wires for some distance, revealing the plaintext letters as they were typed into the machine.

  Whether this was ever successfully exploited on the Berlin intercepts appears doubtful, but the underlying phenomenon was real enough. During World War II a technician at Bell Telephone doing a routine test on a one-time-tape teleprinter encryption device called SIGTOT noticed that every time the message tape advanced one position, a spike appeared on an oscilloscope on the other side of the room. The Bell researchers quickly traced the signals to the electric relays in the teleprinter that were actuated as each character was read: every time their contacts opened they created a small spark, which induced a radio frequency signal. Moreover, the researchers discovered, each of the characters in the five-bit Baudot teleprinter code had its own distinctive pattern of spikes on the oscilloscope, thereby reducing the cryptanalytic challenge for any comparably equipped eavesdropper from an impossible one-time-pad problem to a simple monoalphabetic substitution cipher. The signals could not only radiate through the air for distances of as much as half a mile, but could induce an electrical impulse that could travel for miles or mo
re in nearby conductors like power lines, telephone wires, even water pipes.29

  By 1954 the Soviets appeared to be well aware of the problem, too, and in a comprehensive set of standards issued ostensibly to prevent interference to radio broadcasts by electronic equipment, there were curiously stringent shielding requirements for teleprinter devices. As U.S. researchers began delving more deeply into the matter in the early 1950s they found to their dismay that everything they tested radiated telltale emissions. Cipher machines whose rotors were operated by electric motors could even be exploited by measuring voltage fluctuations on the power lines they were attached to as they drew varying amounts of current; sounds produced by cipher machines or electric typewriters as their mechanisms operated proved an equal giveaway.

  The subsequent discovery of concealed microphones in the code room of the American embassy in Moscow left little doubt in the minds of NSA’s experts that the Soviets were well along in exploiting such “side channel” attacks on cryptographic devices. “Most people were concerned about all the conversations that may have been overheard” by the embassy bugs, an NSA security expert later wrote in an article for the agency’s in-house technical publication, Cryptologic Spectrum. “We were concerned with something else: What could those microphones do to the cryptomachines used there?” The sweep of the embassy also uncovered a large metal grid, embedded six inches deep in the concrete floor of the attic directly over the code room, that apparently was used to collect stray radio frequency emissions from the code machines.

 

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