[8599] in cryptography@c2.net mail archive
Bad PRNGs revisted in FreSSH
daemon@ATHENA.MIT.EDU (Charles M. Hannum)
Wed Feb 14 09:52:42 2001
Date: Mon, 12 Feb 2001 10:28:25 GMT
Message-Id: <200102121028.f1CASP410405@trinity.ihack.net>
From: "Charles M. Hannum" <root@ihack.net>
To: cryptography@c2.net
The newly announced FreSSH, when there is no /dev/urandom available,
uses a `fallback' to seed its PRNG that consists of:
int numfs, whichfs = 0;
struct statfs *mntbuf;
numfs = getmntinfo(&mntbuf, MNT_NOWAIT);
while (whichfs < numfs) {
ssh_rand_feed((void *) mntbuf,
sizeof(struct statfs));
memset(mntbuf, 0, sizeof(struct statfs));
mntbuf++;
whichfs++;
}
I don't think I need to tell people on this list why that's absolutely
horrible; I'm just pointing out that code is still released today with
crap like this. I would have thought we'd learned this lesson years
ago with the AFS, krb4, Netscape, et al vulnerabilities.
