I remember a discussion to the effect that using DSA keys in sshd increases the requirement for random bits available on the system... and that this requirement (was it a 128 bit random number per connection?) presents security problems on systems that don't have a decent source of entropy? Am I misinterpreting those discussions? We are having a problem deploying sshd (no prngd) where sshd refuses to start because it says theres not enough available entropy. Would disabling DSA in sshd prevent the system from becoming "entropy starved"? If I'm missing the point of the latest discussions, someone please correct me.... what was the real meaning of those discussions about using DSA keys in sshd? Thanks, Ed Ed Phillips <ed at udel.edu> University of Delaware (302) 831-6082 Systems Programmer III, Network and Systems Services finger -l ed at polycut.nss.udel.edu for PGP public key
On Fri, 2 Nov 2001, Ed Phillips wrote:> I remember a discussion to the effect that using DSA keys in sshd > increases the requirement for random bits available on the system... and > that this requirement (was it a 128 bit random number per connection?) > presents security problems on systems that don't have a decent source of > entropy? Am I misinterpreting those discussions? > > We are having a problem deploying sshd (no prngd) where sshd refuses to > start because it says theres not enough available entropy. Would > disabling DSA in sshd prevent the system from becoming "entropy starved"?No, you should adjust ssh_prng_cmds to gather more entropy or pester your OS vendor for /dev/random.> If I'm missing the point of the latest discussions, someone please correct > me.... what was the real meaning of those discussions about using DSA keys > in sshd?Read WARNING.RNG -d -- | By convention there is color, \\ Damien Miller <djm at mindrot.org> | By convention sweetness, By convention bitterness, \\ www.mindrot.org | But in reality there are atoms and space - Democritus (c. 400 BCE)
On Sat, 3 Nov 2001 09:46:51 +1100 (EST) Damien Miller <djm at mindrot.org> wrote:> On Fri, 2 Nov 2001, Ed Phillips wrote:> > We are having a problem deploying sshd (no prngd) where sshd refuses to > > start because it says theres not enough available entropy. Would > > disabling DSA in sshd prevent the system from becoming "entropy starved"? > > No, you should adjust ssh_prng_cmds to gather more entropy or pester your > OS vendor for /dev/random.We have the exact same problem here on AIX 3.x. We now use prngd and this completly solve the problem. -- Laurent Papier - Admin. systeme Sdv Plurimedia - <http://www.sdv.fr>
On Mon, 5 Nov 2001, Laurent Papier wrote:> > No, you should adjust ssh_prng_cmds to gather more entropy or pester your > > OS vendor for /dev/random. > > We have the exact same problem here on AIX 3.x. We now use prngd and this > completly solve the problem.Short of pursuading your OS vendor to give you a /dev/random, using PRNGd is the best approach. IMO the built-in entropy code should really be a last resort. -d -- | By convention there is color, \\ Damien Miller <djm at mindrot.org> | By convention sweetness, By convention bitterness, \\ www.mindrot.org | But in reality there are atoms and space - Democritus (c. 400 BCE)
Maybe we should have set internal entropy to --with-internal-entropy at the 3.0 instead of having it default. (Thus having ./configure failure if it does not find entropy) I think most people will ignore messages if ./configure success. - Ben On Tue, 6 Nov 2001, Damien Miller wrote:> On Mon, 5 Nov 2001, Laurent Papier wrote: > > > > No, you should adjust ssh_prng_cmds to gather more entropy or pester your > > > OS vendor for /dev/random. > > > > We have the exact same problem here on AIX 3.x. We now use prngd and this > > completly solve the problem. > > Short of pursuading your OS vendor to give you a /dev/random, using > PRNGd is the best approach. IMO the built-in entropy code should > really be a last resort. > > -d > > -- > | By convention there is color, \\ Damien Miller <djm at mindrot.org> > | By convention sweetness, By convention bitterness, \\ www.mindrot.org > | But in reality there are atoms and space - Democritus (c. 400 BCE) > >
these are in openssl. Manoj Jaitly wrote:> > Hi > > Can anyone help me in finiding the following functions in openssh2.9.9p2, I > did not find these functions any where > > BN_num_bits > BN_bn2bin > BN_init > > Infact all the BN_ related functions. > > Also the MD5_ related functions > > Thanks > Manoj-- wendy palm Cray OS Sustaining Engineering, Cray Inc. wendyp at cray.com, 651-605-9154
On Mon, 5 Nov 2001 mouring at etoh.eviladmin.org wrote:> > Maybe we should have set internal entropy to --with-internal-entropy at > the 3.0 instead of having it default. (Thus having ./configure failure > if it does not find entropy)I really like the idea, but its too late for 3.0. -d -- | By convention there is color, \\ Damien Miller <djm at mindrot.org> | By convention sweetness, By convention bitterness, \\ www.mindrot.org | But in reality there are atoms and space - Democritus (c. 400 BCE)
On Mon, 5 Nov 2001, Manoj Jaitly wrote:> Hi > > Can anyone help me in finiding the following functions in openssh2.9.9p2, I > did not find these functions any where > > BN_num_bits > BN_bn2bin > BN_init > > Infact all the BN_ related functions. > > Also the MD5_ related functionsOpenSSL?s libcrypto -d -- | By convention there is color, \\ Damien Miller <djm at mindrot.org> | By convention sweetness, By convention bitterness, \\ www.mindrot.org | But in reality there are atoms and space - Democritus (c. 400 BCE)