## 13.5. Legal Issues

We discussed the general principles of computer security earlier. Here we will look at how secure communication is built into Apache. But before we do that, we have to look at the legal problems, which are somewhat trickier than the technical ones. This is perhaps not surprising, when one thinks about the social power that effective encryption gives the user.

Obviously, browser and server have to be thinking along the same lines if they are going to collaborate on tricky enterprises like PK encryption and decryption. In this case it is Netscape who calls the tune, with their Secure Sockets Layer (SSL) protocol, which uses the PK algorithm.[64]

> [64]There is a rival scheme called Secure Hypertext Transfer Protocol (SHTTP) that is not widely used. If it is ever adopted by the Internet Engineering Task Force (IETF), who decide what is and isn't an Internet protocol, SSL will be called Transport Layer Security (TLS).

There are two areas of legal concern in making use of PK: patent rights and national security.

### 13.5.1. Patent Rights

The patent position is this:

The Massachusetts Institute of Technology and the Board of Trustrees of the Leland Stanford Junior University have granted Public Key Partners (PKP) exclusive sublicensing rights to the following patents issued in the United States, and all of their corresponding foreign patents: Cryptographic Apparatus and Method ("Diffie-Hellman") No. 4,200,770 Public Key Cryptographic Apparatus and Method ("Hellman-Merkle") No. 4.318,582 Cryptographic Communications System and Method ("RSA") No. 4.405,829 Exponential Cryptographic Apparatus and Method ("Hellman-Pohlig") No. 4,424,414. These patents are stated by PKP to cover all known methods of practicing the art of Public Key encryption, including the variations collectively known as El Gamal. Public Key Partners has provided written assurance to the Internet Society that parties will be able to obtain, under reasonable, nondiscriminatory terms, the right to use the technology covered by these patents.[65]

> [65]SSL Protocol Netscape Corporation.

First, there is a divergence between the United States and the rest of the world in the matter of patenting computer programs. The rest of the world follows the old maxim that you cannot patent an idea or a form of words, but you have to patent an actual device. A computer program is not a device, so you cannot patent it. The United States, on the other hand, adopts what looks like a convenient fiction to everyone else and says that a computer running a particular program is different from the same computer running another program because the patterns of 0s and 1s in its memory and CPU registers are different. A program is therefore a patentable device.

However, the RSA algorithm was explained in print before the patent was applied for. In most countries, that would be an absolute bar to the granting of a patent, but the United States has another difference in its patent law: patents are granted to the first to invent. In the ordinary course of affairs, you invent something before you describe it in print, so prior disclosure is not as much of a problem in the United States as it is elsewhere, but the RSA patent may yet be overturned.

For the moment, however, the patent seems to be good and normal, and patent law applies to the RSA algorithm as it does to any other patented device: you may not use a patented program for commercial purposes in the United States without a license from the patentee. This also applies to programs brought into the United States from abroad that use the basic algorithms. So, the doughty Australian, Eric Young, who wrote the Secure Sockets Layer libraries from basic number theory, finds to his annoyance that his code is subject to U.S. law and complains that in the United States people who use his code have to pay a license fee to "people he and they have never met."

But this is no different from any other patent. If, in the privacy of your Australian kitchen, you make a copy of an eyebrow tweezer patented in the United States and give it to someone who uses it commercially in their hairdressing salon in California, the owner of the patent can legally demand a fee, even though neither of you have met him and the tweezers were made in patent-free Australia. This is how patents work.

Patents have to be applied for and granted country by country. The fact that a device is patented in the United States gives it no automatic protection in Thailand. And, in fact, no other country in the world recognizes software patents, so the commercial license fee is only payable in the United States.

U.S. licenses for the public key algorithms used in Apache are to be had from PKP on payment of a negotiable fee.

### 13.5.2. National Security

The patent issue is relatively straightforward; that of security is byzantine. The problem is that unbreakable encryption is a matter of extreme national military importance. It might conceivably be argued that Germany's reliance on vulnerable encryption lost her World War II; it certainly cost her enormous losses in lives and matériel.

As a result, public-key encryption technology, which is unbreakable provided the key is big enough, is regarded by certain countries, including the United States, as a munition of war on a par with the design of an H-bomb warhead, and it may not be exported outside the United States or Canada (which is regarded as the same defense zone).

In view of the fact that you can go to any good library, as Eric Young did, read the algorithms, and write your own code, this is rather a silly stance to take. But it is the stance that the U.S. government takes, and they compound the problem[66] by saying that PK encryption using short keys (40 bits) is all right, but using longer keys is not.[67] The difference is simply setting a variable in the source code.

> [66]The U.S. Department of Defense has gotten itself into a similar tangle over the Global Positioning System (GPS). Originally designed as a military device to give positions accurate to a meter or so, it is degraded for public use so that the accuracy is something like 20 meters in order that the United States' enemies should not profit by it. But during the Gulf War, when many U.S. field units brought their own civilian GPS sets to supplement the meager military supply, the degradation in the civilian channels was switched off so that all users, enemy as well as friendly, had full military precision. Once the war was over, the degradation was switched on again!

> [67]Actually, it is more complex than this. The actual encryption used is 128-bit symmetric encryption, using a random key that is exchanged using PK encryption. For export, only 40 bits of the 128 bits are sent encrypted. The other 88 bits are in the clear. But enough of the technical details -- the essence is that the encryption is weak enough to be broken without spending too much.

One of the authors (BL) of this book has a T-shirt on which is printed a PK algorithm. You would think that if he boards an intercontinental aircraft in the United States wearing this shirt, he commits a very serious federal offense. But it seems, to put an even more bizarre twist to the story, that it is not illegal to export listings of encryption programs.[68] Presumably, the enemies of freedom cannot read.

> [68]Actually, the T-shirt anticipates this and includes a computer-readable version (in the form of a barcode), especially to make the T-shirt unexportable. On the other side of the coin, Bruce Schneier's excellent Applied Cryptography, which includes source code for virtually every crypto algorithm known to man, is freely exportable (at least, as long as you take the floppy out first).

As far as U.S. law is concerned, the world divides into three geographical areas:

- The United States

- Canada

- The rest of the world

In the United States, people can use full-strength PK algorithms but must pay a license fee to PKP. And you can import and use illegal encryption software from abroad, without fear of trouble from the Defense Department; however, you should pay patent license fees to PKP, so there is not much point.

In Canada, you can use the full-strength encryption exported from the United States, and you don't have to pay a license fee because Canada does not recognize patents on software.

In the rest of the world, you can use feeble encryption exported from the United States or full-strength encryption brewed locally. If you can't get it locally, there are plenty of people in Moscow and other places who will give you the full-strength U.S. product.

Britain used to follow the U.S. ban on exports of munitions of war, but now the following two instruments apply. (We think! The U.K. government is no more interested in making it easy to figure out what is going on than the U.S. government, it seems.)

- The Export of Goods (Control) Order, which is United Kingdom legislation

- Dual-Use and Related Good (Export Control) Regulations, which are European Community law

These laws are rather more lenient than U.S. law, and, in particular, Apache-SSL is probably exempt as an over-the-counter product. Anyone who wants to get into this business should seek legal advice, since the British government is no fonder than any other of explaining in clear and simple terms what the law actually means in practice. However, it also is very shy of making a fool of itself in court, so the situation does not seem to be draconian, though it is more worrying than it was. At the time of this writing (summer 1998), the new Labor government had been in power about a year. The manifesto that led to their election had made anodyne noises about encryption, but as time went on, it appeared that the American government was making strenuous efforts to get Britain and the European Community to adhere to its unsatisfactory policies. The situation may have been complicated by British prime minister Blair's need to get President Clinton's active help in reducing U.S. support to the IRA in order to try to resolve the Irish war. In the process he may have been obliged to give unpublished undertakings on other issues -- which may have included encryption.

The proposal being touted comes from Royal Holloway College, which is part of London University, and the European Commission Council DGIII, and would establish a distributed, secure key escrow system. It would be illegal to use a key that was not held in escrow. There are at least two problems with this policy:

- One corrupt official within the escrow system could throw every "secure" site open to the underworld.

- It would not bother criminals at all.

It is rather as though a new kind of unbreakable door lock had been invented. The government, afraid that behind these new doors, citizens are going to do unspeakable things, orders that every owner of the new lock has to deposit a copy of the key at the police station. The criminals do not bother, and their friends the corrupt policemen give them all the honest peoples' keys.

The difficulty with trying to criminalize the use of encrypted files is that they cannot be positively identified. An encrypted message may be hidden in an obvious nonsense file, but it may also be hidden (by steganography) in unimportant bits in a picture or a piece of music or something like that. Conversely, a nonsense file may be an encrypted message, but it may also be a corrupt ordinary file or a proprietary data file whose format is not published. There seems to be no reliable way of distinguishing between the possibilities except by producing a decode. And the only person who can do that is the "criminal," who is not likely to put himself in jeopardy.

France, as always very practical in matters of national security, bans PK encryption without a license from the government, and the government does not issue licenses. Use of the technology in France, let alone its export, is a crime. We would be interested to hear reliable accounts of the position in other countries for inclusion in later editions of this book.

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