From: Bruce Schneier <schneier@winternet.com>
Date: Wed, 3 Jan 1996 15:02:42 +0800
To: cypherpunks@toad.com
Subject: no subject (file transmission)
Message-ID: <199601030329.VAA04190@parka>
MIME-Version: 1.0
Content-Type: text


                  APPLIED CRYPTOGRAPHY, Second Edition
                               ERRATA
                     Version 1.0 - 3 January 1996


This errata includes all errors I have found in the book, including minor
spelling and grammatical errors.  Please distribute this errata sheet to
anyone else who owns a copy of the book.


Page 11:  Line 18, the reference should be "[703]" and not "[699]".

Page 13:  Fifth paragraph, first sentence, should read: "The German Enigma
had three rotors, chosen from a set of five,...."

Page 14:  The last sentence should read:  "The smallest displacement that
indicates a multiple of the key length is the length of the key."

Page 16:  Third line from the bottom, "1.44" makes more sense as "1.544".

Page 18:  Table 1.1, second item.  1 in 4,000,000 is 2^22.

Page 53:  Second to last sentence about SKEY should read: "Similarly, the
database is not useful to an attacker."

Page 61:  Step (3), the second message should contain A instead of B.

Page 62:  In the third line, there's a comma missing.

Page 63:  Second protocol, step (2), the second message should be
"S_T(C,K_C)".

Page 70:  In the first step (4), the equation should be "R XOR S = M".  In
the second step (2), it should be "to generate U".

Page 77:  In step (2), the message is signed with Trent's private key.  And
T_n is mistakenly both the time and the timestamp.

Page 82:  Fourth line from the bottom, the correct expression is "up and
died."

Page 99:  Tenth line from the bottom, delete the second word: "will".

Page 104:  Graph isomorphism has never been proven to be an NP-Complete
problem.  It does seem to be hard, and is probably useful for cryptography.

Page 105:  In Step (2), Peggy gives Victor a copy of H'.

Page 112:  Step (1) should read "Alice takes the document and multiplies it
by a random value."

Page 116:  The protocol could be worded better.  Step (3) should begin:
"Alice decrypts Bob's key twice, once with each of her private keys."  Step
(4) should begin: "Alice encrypts both of her messages, each with a
different one of the DES keys...."

Page 126:  The "Voting with Blind Signatures" protocol is a little more
complicated.  The voter does not send all the blinding factors in step (2). 
The CTF requests 9 of 10 blinding factors in step (3), and the voter sends
only those blinding factors to the CTF.

Page 134:  Another problem with this protocol is that there are numerous
ways that various participants can cheat and collude to find out the salary
of another participant.  These cheaters can misrepresent their own salaries
during their attack.

Page 135:  Lines 13-14; technically Alice and Bob get no additional
information about the other's numbers.

Page 136:  Lines 14-15; technically Alice and Bob get no additional
information about the other's numbers.

Page 144:  Line 27, the odds should be "1 in n".  Line 29, "step (2) should
be "step (1)".

Page 161:  In the eleventh line from the bottom, "harnesses" should be
"harnessed".

Page 181:  Line a should read "he does not know it" instead of "he does
know it".

Page 195:  In line 13, the reference number should be [402].

Page 201:  Error Propagation, lines 5-6.  The sentence should read: "In 8-
bit CFB mode, 9 bytes of decrypted plaintext are garbled by a single-bit
error in the ciphertext."

Page 202:  Third to last line, toggling individual bits does not affect
subsequent bits in a synchronous stream cipher.

Page 203:  Section 9.8, both equations should be "S_i = E_K(S_(i-1))".

Page 209:  Table 9.1.   CFB, Security: Bits of the last block can be
changed, not the first.  CFB, Efficiency: The speed is the same as the
block cipher only in 64-bit CFB.  CFB and OFB, Efficiency: "Ciphertext is
the same size as the plaintext" should be a plus.

Page 217:  The Table 10.1 headers got garbled.  They should be:
"Algorithm", "Confidentiality", "Authentication", "Integrity", and "Key
Management".

Page 246:  The last line should be: "#define isEven(x) ((x & 0x01) == 0)".

Page 249:  Line 9, "Euclid's generalization" should be "Euler's
generalization".

Page 251:  Lines 20-21.  The sentence should read: "For example, there are
11 quadratic residues mod 35: 1, 4, 9, 11, 14, 15, 16, 21, 25, 29, and 30." 
See page 505 for more details.

Page 258:  In line 27, his name is spelled "Chandrasekhar".

Page 275:  Table 12.4; it should be a "48-Bit Input".

Page 281:  In line  4, "minuscule" is misspelled as "miniscule".

Page 287:  In Figure 12.6, there should be no period in X or Y.

Page 292:  Second line, "b_24" should be "b_26".  In line 10, "1/2 - .0061"
should be "1/2 + .0061".

Page 295:  Third line from the bottom, 2^(120/n) should be (2^120)/n.

Page 300:  In the first line, "56" should be "48".

Page 319:  In line 11, Section "25.13" should be "25.14".

Page 322:  Last line, the chip is 107.8 square mm.

Page 338:  In Figure 14.3 and in the first line, "f" should be "F".

Page 340:  Second equation should be "mod 256".

Page 341:  The current variants of SAFER are SAFER SK-40, SAFER SK-64, and
SAFER SK-128, all with a modified key schedule, in response to a
theoretical attack by Lars Knudsen presented at Crypto '95.

Page 345:  Lines 10 and 11; the + should be a -.

Page 346:  The reference number for BaseKing should be [402].

Page 352:  In line 8, that second "l" should be an "r".

Page 358:  In the decryption equation of Davies-Price mode, the final D
should be an E.

Page 362:  In the first equation, P is used to indicate both padding and
plaintext.  If P is plaintext and p is padding, then the equation should
be: C = E_K3(p(E_K2(p(E_K1(P))))).

Page 362:  Figure 15.2 is wrong.  The middle and top rows of "Encrypt," and
the plaintext feeding them, are shifted right by 1/2 block from where they
should be.

Page 363:  The parenthetical remark would be clearer as: "encryption with
one of n different keys, used cyclically".

Page 363:  Second to last line, the equation should have an I_2 in place of
the I_1.

Page 367:  Second equation, "P XOR K_3" should be "C XOR K_3".

Page 369:  A maximal period linear congruential generator as a period of m,
not m-1.

Page 375:  Third paragraph should read:  "It is easy to turn this into a
maximal period LFSR.  The highest exponent is the size of the register, n. 
Number the bits from n-1 to 0.  The numbers, including the 0, specify the
tap sequence, counting from the left of the register.  The x^n term of the
polynomial stands for the input being fed into the left end."  The next
paragraph is wrong.

Page 379:  Second line of code has an extra close parentheses.

Page 380:  The forth line should begin: "On the other hand, an
astonishingly...."

Page 393:  In Figure 16.16, there should be an arrow from b_4 to the Output
Function.

Page 393:  Second sentence should be: "It's a method for combining multiple
pseudo-random streams that increases their security."

Page 429:  The second sentence should be: "It returns a fixed-length hash
value, h."

Page 431:  In step (2), "prepend" instead of "append".

Page 440: In item 3, there is an "AND" missing in the equation.

Page 441:  The compression function of MD2 is confusing without the
indentations.  The two for-loops are nested, and include the next two
statements.

Page 444:  In figure 18.7, the a, b, c, d, and e variables are backwards.

Page 445:  Line 14, SHA should be compared to MD4.

Page 447:  Lines 3-4 should read: "...CBC in [1145], CBC in [55,56,54]...."

Page 449:  Figure 18.9, M_i and H_i-1 in the upper-left diagram should be
reversed.

Page 456:  Table 18.2.  Encryption speed should be in "kilobytes/second",
and "SNEERU" should be "SNEFRU".

Page 457:  Lines 3 and 4, the ending "-1" and "-2" should be superscripts.

Page 465:  In the third line of text, the number should be n^-1.

Page 470:  The second to last line is missing an "is".

Page 480:  An additional reference for elliptic-curve cryptosystems is N.
Koblitz, A Course in Number Theory and Cryptography, Springer-Verlag, 1988. 
This is an excellent book, and omitting it was an oversight.

Page 489:  Caption to Table 20.3 should specify an "80386 33 MHz personal
computer".

Page 495:  In Step (8), the constant should be "0x7fffffff".

Page 497:  Delete the fourth equation in the list of verification
equations.

Page 499:  ESIGN, seventh line:  "m-1 should be "n-1".

Page 505:  In step 3, the third sentence should be:  "If Victor's first bit
is a 1, then s_1 is part of the product...."

Page 514:  In step (1), Alice must sent X to Bob.

Page 515:  In line 1, "commutitive" is misspelled as "communitive".

Page 515:  Hughes.  Step (2): In order for step (4) to work, y must be
relatively prime to n-1 else the inverse function in step (4) won't work. 
If n is a strong prime such that (n-1)/2 is also prime, then y can be any
odd random large integer except for (n-1)/2.  In step (4), Bob computes:
z=y^-1 mod (n-1).

Page 516:  In the Station-to-Station protocol, the exponentiation is
missing.  In step (1), Alice sends Bob g^x mod p.  In step (2), Bob
computes the shared key based on g^x mod p and y.  He signs g^x mod p and
g^y mod p, and encrypts the signature using k.  He sends that, along with
g^y mod p, to Alice.  In step (3), Alice sends a signed message consisting
of g^x mod p and g^y mod p, encrypted in their shared key.

Page 529:  Line 13 should be a polynomial of degree 5, not 6.

Page 535:  The technique wherein Mallory leaks 10 bits of DSA secret per
signature, can be sped up by a factor of 16 or so.  Instead of choosing a
4-bit block randomly and then searching for a k that leaks
the correct 14 bits, he can just use the low 4 bits of r to select the
block of the signature to leak (no need to have an opaque subliminal
channel) and he only has to check an average of 1024 k values until the
bits sent out over the 10 subliminal channels match the 10 bits of the
secret selected by r = (g^k mod p) mod q.

Page 568:  In the Kerberos Version 5 Messages, step 3, the final "s" should
not be subscripted.

Page 586:  Figure 24.7, in the key the arrow should point from y to x.

Page 586:  Seventh line, "revokation" should be spelled "revocation".

Page 589:  Section 24.15, fourth line:  "Nambia" should be "Namibia".

Page 592:  The equation is wrong.  The structure of the LEAF is
"E_KF(U,E_KU(K_S),C)", where U is the 32-bit unit ID, K_S is the 80-bit
session key, and C is a 16-bit checksum of K_S and the IV (and possibly
other material) used by the receiving chip to ensure that it has a valid
LEAF.

Page 604:  Fourth line from the bottom should read: "to U.S. patent law."

Page 606:  In lines 12 and 13, the cross-references are to chapter 18.

Page 607:  In Table 25.4, the column headers are reversed.

Page 610:  Sixth line should read "it is filed", not "it is filled".

Page 683:  In reference 210, the title of the paper is "A Comparison of
Three Modular Reduction Functions".

Page 705:  In reference 727, subscript should be a superscript.

This errata is updated periodically.  For a current errata sheet, send a
self-addressed stamped envelope to:   Bruce Schneier, Counterpane Systems,
101 East Minnehaha Parkway, Minneapolis, MN  55419; or send electronic mail
to: schneier@counterpane.com.