similar to: upgrade 2.2 to 2.3, diffie-hellman, ssl_min_protocol

Thanks Joseph, Aki, but something missing from upgrade document, where does the dh param file go? I located ssl-parameters.dat so I will put it there. Quoting Joseph Tam <jtam.home at gmail.com>: > On Fri, 22 Jun 2018, Joseph Tam wrote: > >> However, recent advances make this condition obsolete [*] and not >> really safer, so a much faster way to generate a DH key is

On Fri, 22 Jun 2018, Aki Tuomi wrote: >> Do I need to make a fresh dh.pem? The upgrade doc tells how to convert >> ssl-parameters.dat but how to make a new one? > > ... or you can make a fresh one using openssl > gendh 4096 > dh.pem This also works openssl dhparam -out dh.pem 4096 > Note that this will require quite a lot of entropy, so you should > probably

> On 22 June 2018 at 10:18 tai74 at vfemail.net wrote: > > > > hi sorry if question was asked already. Was reading > https://wiki2.dovecot.org/Upgrading/2.3 > > first I'm confused on diffie hellman parameters file. I never set up > ssl-parameters.dat before (should i have? do I have one that was > automatically made for me by dovecot?) > > Do I need

On Fri, 22 Jun 2018, Joseph Tam wrote: > However, recent advances make this condition obsolete [*] and not > really safer, so a much faster way to generate a DH key is > > openssl dhparam -dsaparam -out dh.pem 4096 > > DH generation is a one time operation, so if you're paranoid and you've > got time to burn, go ahead and generate the "safe" DH key. >

> On 19 August 2018 at 20:55 Aki Tuomi <aki.tuomi at dovecot.fi> wrote: > > > > > On 19 August 2018 at 19:38 Kai Schaetzl <maillists at conactive.com> wrote: > > > > > > Aki Tuomi wrote on Sun, 19 Aug 2018 18:21:31 +0300: > > > > > Just generate new parameters on some machine with good entropy source. > > > > So, if

A few questions regarding the OpenSSH support for the Diffie Hellman key exchange algorithms: (1) Are the diffie-hellman-group-exchange-sha256", "diffie-hellman-group-exchange-sha1" , "diffie-hellman-group14-sha1" "diffie-hellman-group1-sha1" (as defined in RFCs 4253 and RFC 4419) the complete list of key exchange algorithms supported by OpenSSH? (2) Is there a

I'm not sure if collision resistance is required for DH key derivation, but generally, SHA-1 is on its way out. If it's possible (if there's not a very large percentage of servers that do not support anything newer), it should be disabled.

That doesn't seem to be the case. See https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-57pt1r4.pdf (5.6.1 Comparable Algorithm Strengths) On Fri, Feb 15, 2019 at 8:28 AM Darren Tucker <dtucker at dtucker.net> wrote: > > On Fri, 15 Feb 2019 at 16:00, Yegor Ievlev <koops1997 at gmail.com> wrote: > > I don't think there is any point to generate so

e.g. can we make it throw warnings etc. rsa-sha2-256 and rsa-sha2-512 are fine, they use PSS. On Sun, Jan 20, 2019 at 1:55 AM Yegor Ievlev <koops1997 at gmail.com> wrote: > > Also can we do anything with ssh-rsa? It uses both SHA-1 and > deprecated PKCS#1 padding. If it's used to sign certificates, there's > no additional protection of SHA-2 hashing before SHA-1

I?m setting up Dovecot using Homebrew on a new server and am getting this when I try to login via IMAP: Nov 13 14:13:35 auth: Debug: auth client connected (pid=30719) Nov 13 14:13:35 imap-login: Info: Aborted login (no auth attempts in 0 secs): user=<>, rip=::1, lip=::1, secured, session=<gM0HNIN6HtoAAAAAAAAAAAAAAAAAAAAB> Nov 13 14:18:33 auth: Debug: Loading modules from directory:

Currently, dovecot generates two primes for Diffie-Hellman key exchanges: a 512-bit one and a 1024-bit one. In light of recent events, I think it would be wise to add support for 2048-bit primes as well, or even better, add a configuration option that lets the user select a file (or files) containing the DH parameters In recent years, there has been increased interest in DH especially in its

I have been reading up on TLS and Dovecot and came across this URL: https://www.weakdh.org/sysadmin.html which recommended these settings for Dovecot. I would like to know if they are correct? Some much documentation on the web is pure garbage. Dovecot These changes should be made in /etc/dovecot.conf Cipher Suites

I referred to the fact that there is no value for 4096-bit groups at all. For higher strengths than 128 bits one should probably not use non-EC crypto at all, as the document suggests. On Fri, Feb 15, 2019 at 9:19 AM Darren Tucker <dtucker at dtucker.net> wrote: > > On Fri, 15 Feb 2019 at 16:45, Yegor Ievlev <koops1997 at gmail.com> wrote: > > That doesn't seem to be

https://bugzilla.mindrot.org/show_bug.cgi?id=2515 Bug ID: 2515 Summary: Implement diffie-hellman-group{14,15,16)-sha256 Product: Portable OpenSSH Version: -current Hardware: All OS: All Status: ASSIGNED Severity: enhancement Priority: P3 Component: ssh Assignee: dtucker at

On Fri, 2019-02-15 at 15:57 +1100, Darren Tucker wrote: > That was the original intent (and it's mentioned in RFC4419) however > each moduli file we ship (70-80 instances of 6 sizes) takes about 1 > cpu-month to generate on a lowish-power x86-64 machine. Most of it > is > parallelizable, but even then it'd likely take a few hours to > generate > one of each size. I

Can we disable diffie-hellman-group14-sha1 too? On Thu, Feb 14, 2019 at 10:23 PM Mark D. Baushke <mdb at juniper.net> wrote: > > Hi John, > > The short answer is YES. > > Jon DeVree <nuxi at vault24.org> writes: > > > I ask because the removal of diffie-hellman-group-exchange-sha1 happened > > accidently in 7.8 due to a mistake in a change to

https://bugzilla.mindrot.org/show_bug.cgi?id=2291 Bug ID: 2291 Summary: ssh -Q kex lists diffie-hellman-group1-sha1 twice Product: Portable OpenSSH Version: 6.7p1 Hardware: Other OS: Linux Status: NEW Severity: minor Priority: P5 Component: sftp-server Assignee:

I ask because the removal of diffie-hellman-group-exchange-sha1 happened accidently in 7.8 due to a mistake in a change to readconf.c. I noticed this and filed a bug about it along with a patch to fix readconf.c to use KEX_CLIENT_* like it used to: https://github.com/openssh/openssh-portable/commit/1b9dd4aa https://bugzilla.mindrot.org/show_bug.cgi?id=2967 Its clear the removal was unintentional

Hi, I am trying to debug a new (to me) printer, that should be able to use AD (for LDAP / address book lookups as well as authentication). It's been a while since I needed to dump traffic with wireshark; and evidently it's got harder since I last tried :) I have generated a wireshark dump on my DC, to see what the printer is trying to do, using: dc1$ sudo tcpdump host myprinter and port

Hello, I'd like to inform you that the next release of WinSCP SFTP client (version 5.7.5) will support Diffie-Hellman group exchange as specified by RFC 4419. http://winscp.net/tracker/show_bug.cgi?id=1345 So I'd like to ask you to kindly update the check in compat_datafellows() to WinSCP_release_4* WinSCP_release_5.0* WinSCP_release_5.1* WinSCP_release_5.2* WinSCP_release_5.5*