Who leaked the details of a CIA-Mossad plot against Iran?

James Risen, The New York Times reporter for national security and intelligence affairs, has been asked to testify as part of an investigation aimed at revealing who leaked apparently confidential information about the planning of secret Central Intelligence Agency and Mossad missions concerning Iran's nuclear program.
Risen included this information in his book, "State of War: The Secret History of the CIA and the Bush Administration," which was published in 2006. In the book, he discusses a number of ideas which he says were thought up jointly by CIA and Mossad operatives to sabotage Iran's nuclear capabilities.
One of these ideas was to build electromagnetic devices, smuggling them inside Iran to sabotage electricity lines leading to the country's central nuclear sites. According to the plan, the operation was supposed to cause a series of chain reactions which would damage extremely powerful short circuits in the electrical supply that would have led to failures of the super computers of Iran's nuclear sites.