[125] in The Cryptographic File System users list
cmkdir coding question
daemon@ATHENA.MIT.EDU (Rob Stampfli)
Sat Feb 27 13:35:11 1999
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Date: Sat, 27 Feb 99 13:28 EST
From: res@colnet.cmhnet.org (Rob Stampfli)
To: cfs-users@research.att.com
Subject: cmkdir coding question
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I took some time this morning to look into how the ..k file works.
Of what I think I understand of it, one thing puzzles me:
Around line 145 of cmkdir.c (cfs-1.4.0beta2), there is the following code
snippet:
/* now we xor in some truerand bytes for good measure */
bcopy(&k,ekey,32); /* assumes key material < 32 bytes */
for (i=0; i<32; i++) {
ekey[i] ^= randbyte();
}
Since XORing anything with unsaved random data produces random data,
what is the purpose of the bcopy()?
--
Rob Stampfli rob@colnet.cmhnet.org The Bill of Rights: It was a
614-864-9377 HAM RADIO: kd8wk@w8cqk.oh good thing while it lasted...
