Appendix C

Appendix C of the XKMS Vesion 2 Candidate Recommendation, entitled Sample 
Protocol Exchanges, contains examples of key derivations, some of which 
appear not to be accurate.  I enclose my suggested corrections below.

Section 8.1 (Use of Limited-Use Shared Secret Data) says that "All space and 
control characters are removed." Given sections C.1.2 and C.1.3, this 
suggests that a hyphen is a control character. For
the sake of clarity I propose using "punctuation characters" instead of or 
in addition to "control characters".

Also, it might be more appropriate to call the derived quantities "Secret 
Keys" as opposed to "Private Keys".


C.1.2 Bob Registration Authentication Key
Authentication Data
3N9CJ-JK4JK-S04JF-W0934-JSR09-JWIK4
Converted Authentication Data
[33][6e][39][63][6a][6a][6b][34] [6a][6b][73][30][34][6a][66][77] 
[30][39][33][34][6a][73][72][30]
[39][6a][77][69][6b][34]
Key = HMAC-SHA1 (Converted Authentication Data, 0x1)
[92][33][7c][7c][3e][8d][3b][7a] [cf][11][59][89][36][64][56][69] 
[95][4f][8f][d7]


C.1.3 Bob Registration Private Key Encryption
Authentication Data
3N9CJ-K4JKS-04JWF-0934J-SR09JW-IK4
Converted Authentication Data
[33][6e][39][63][6a][6b][34][6a] [6b][73][30][34][6a][77][66][30] 
[39][33][34][6a][73][72][30][39] [6a][77][69][6b][34]
First Block = HMAC-SHA1 (Converted Authentication Data, 0x4)
[78][f1][e7][b1][b3][fd][0c][bc] [96][04][e7][01][4f][33][78][d3] 
[0b][c8][5f][bd]
Key = First Block XOR 0x4
[7c][f1][e7][b1][b3][fd][0c][bc] [96][04][e7][01][4f][33][78][d3] 
[0b][c8][5f][bd]
Second Block = HMAC-SHA1 (Converted Authentication Data, Key)
[1e][7f][e1][b0][ab][d0][f8][09] [2e][28][f3][9d][14][a8][d0][83] 
[2e][ab][ea][22]
Final Private Key
[78][f1][e7][b1][b3][fd][0c][bc] [96][04][e7][01][4f][33][78][d3] 
[0b][c8][5f][bd][1e][7f][e1][b0]


C.1.4 Bob Recovery Private Key Encryption
Authentication Data
A8YUT vuhhu c9h29 8y43u h9j3i 23
Converted Authentication Data
[61][38][79][75][74][76][75][68] [68][75][63][39][68][32][39][38] 
[79][34][33][75][68][39][6a][33] [69][32][33]
Private Key
[91][8c][67][d8][bc][16][78][86] [dd][6d][39][19][91][c4][49][6f] 
[14][e2][61][33][6c][15][06][7b]


C.2.1 Alice Pass Phrase Computation

The values are correct, but the lines
Pass Phrase Pass 1 HMAC-SHA1 (Converted Authentication Data, 0x1)
Pass Phrase Pass 2 = HMAC-SHA1 (Pass Phrase Pass 1 , 0x2

should read
Pass Phrase Pass 1 HMAC-SHA1 (Converted Authentication Data, 0x2)
Pass Phrase Pass 2 = HMAC-SHA1 (Pass Phrase Pass 1 , 0x3)


C.2.2 Bob Pass Phrase Computation

The values are correct, but the lines
Pass Phrase Pass 1 HMAC-SHA1 (Converted Authentication Data, 0x1)
Pass Phrase Pass 2 = HMAC-SHA1 (Pass Phrase Pass 1 , 0x2

should read
Pass Phrase Pass 1 HMAC-SHA1 (Converted Authentication Data, 0x2)
Pass Phrase Pass 2 = HMAC-SHA1 (Pass Phrase Pass 1 , 0x3)


Regards
Tommy

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Received on Wednesday, 7 April 2004 06:26:14 UTC