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--- chopchoptheory [2006/11/19 16:12] – darkaudax
+++ chopchoptheory [2010/11/21 15:46] (current) – typos sleek
@@ Line 30: / Line 30: @@
   * D0 to D4 remain the same.
   * R5 = I3 + K5 = I3 + (D5+D5) + K5 = (I3+D5) + (D5+K5) = X + S5.
-  * R6 to R8 are computed by reversing one crc step based on the value of X. There's a correspondence among I2-I0 and J3-J1 because crc shiftes them back but D5 "pushes" them forward again. They are not necessarily keeping the same values, but their difference depends only on X, which we have guessed.
+  * R6 to R8 are computed by reversing one crc step based on the value of X. There's a correspondence among I2-I0 and J3-J1 because crc shifts them back but D5 "pushes" them forward again. They are not necessarily keeping the same values, but their difference depends only on X, which we have guessed.
   * J0 depends only on X. K9 = S9 + J0. We have guessed the last message byte and the last byte of keystream.
@@ Line 36: / Line 36: @@
 By doing this, we have found a valid frame 1 byte shorter than original one, and we have guessed one byte of keystream. This process can be induced to get the whole keystream.
+For additional detailed descriptions see:
+  * [[http://www.netstumbler.org/showthread.php?t=12489|Chopchop Attack]] in the original Netstumbler thread.
+  * [[http://www.informit.com/guides/printerfriendly.asp?g=security&seqNum=196|Byte-Sized Decryption of WEP with Chopchop, Part 1]] and [[http://www.informit.com/guides/printerfriendly.asp?g=security&seqNum=197|Byte-Sized Decryption of WEP with Chopchop, Part 2]]