送交者: gentoo 于 2006-5-01, 04:23:34:
回答: Unix之父Ken Thompson的拿图灵奖的演讲就是... 由 gentoo 于 2006-4-30, 21:18:49:
Things I told is just blah blah.
But I really read the Turing Award Lecture.
Anyway, Ken Thompson's backdoor is a famous story.
The actual bug I planted in the compiler would match code in the UNIX "login" command. The replacement code would miscompile the login command so that it would accept either the intended encrypted password or a particular known password. Thus if this code were installed in binary and the binary were used to compile the login command, I could log into that system as any user.
Such blatant code would not go undetected for long. Even the most casual perusal of the source of the C compiler would raise suspicions.
The final step is represented in Figure 7. This simply adds a second Trojan horse to the one that already exists. The second pattern is aimed at the C compiler. The replacement code is a Stage I self-reproducing program that inserts both Trojan horses into the compiler.