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Special collection increasingly involves supply-chain tampering. SCS routinely intercepts equipment such as routers being exported from the USA, adds surveillance implants, repackages them with factory seals and sends them onward to customers. And an extreme form of supply-chain tampering was when the NSA covertly bought Crypto AG, a Swiss firm that was the main supplier of cryptographic equipment to non-aligned countries during the Cold War; I tell the story in more detail later in section 26.2.7.1.

Bullrun is the NSA codename, and Edgehill the GCHQ one, for ‘crypto enabling’, a $100m-a-year program of tampering with supplies and suppliers at all levels of the stack. This starts off with attempts to direct, or misdirect, academic research³; it continued with placing trusted people on standards committees, and using NIST's influence to get weak standards adopted. One spectacular incident was the Dual_EC_DRBG debacle, where NIST standardised a random number generator based on elliptic curves that turned out to contain an NSA backdoor. Most of the actual damage, though, was done by restrictions on cryptographic key length, dovetailed with diplomatic pressure on allies to enforce export controls, so that firms needing export licenses could have their arms twisted to use an ‘appropriate’ standard, and was entangled with the Crypto Wars (which I discuss in section 26.2.7). The result was that many of the systems in use today were compelled to use weak cryptography, leading to vulnerabilities in everything from hotel and car door locks to VPNs. In addition to that, supply-chain attacks introduce covert vulnerabilities into widely-used software; many nation states play this game, along with some private actors [892]. We'll see vulnerabilities that result from surveillance and cryptography policies in one chapter after another, and return in Part 3 of the book to discuss the policy history in more detail.