similar to: Guessing in key exchange

https://bugzilla.mindrot.org/show_bug.cgi?id=2521 Bug ID: 2521 Summary: subtract buffer size from computed rekey limit to avoid exceeding it Product: Portable OpenSSH Version: 6.8p1 Hardware: amd64 OS: Linux Status: NEW Severity: minor Priority: P5 Component: sshd

That's true for block ciphers, but ChaCha20+poly1305 is a stream cipher. On Wed, 29 Mar 2023, Robinson, Herbie wrote: > > I?m hardly an expert on this, but if I remember correctly, the rekey rate > for good security is mostly dependent on the cipher block size.? I left my > reference books at home; so, I can?t come up with a reference for you, but I > would take Chris?

I'm hardly an expert on this, but if I remember correctly, the rekey rate for good security is mostly dependent on the cipher block size. I left my reference books at home; so, I can't come up with a reference for you, but I would take Chris' "I'm deeply unsure of what impact that would have on the security of the cipher" comment seriously and switch to a cipher with a

I plan to use ssh as the secure transport of a VPN. (Yes I know there are other solutions but...) These tunnels may be up for a long time, days or weeks, and escape characters will be turned off because I'll be passing binary data so I can't force a rekey with that method. Since the ssh spec says one should rekey every hour, I plan to patch the ssh client to implement an auto-rekey

I was wondering if there was something specific to the internal chacha20 cipher as opposed to OpenSSL implementation. I can't just change the block size because it breaks compatibility. I can do something like as a hack (though it would probably be better to do it with the compat function): if (strstr(enc->name, "chacha")) *max_blocks = (u_int64_t)1 << (16*2);

On Wed, 29 Mar 2023, Chris Rapier wrote: > I was wondering if there was something specific to the internal chacha20 > cipher as opposed to OpenSSL implementation. > > I can't just change the block size because it breaks compatibility. I can do > something like as a hack (though it would probably be better to do it with the > compat function): > > if

Hi, I downloaded setupssh-7.3p1-2.exe for Windows x64. I created private public keys and set it up accordingly. After entering the passphrase, I see authentication succeeded message but then the connection to the remote host gets closed immediately. Some of the Client output: ************************ ... Enter passphrase for key '/home/user2/.ssh/id_rsa': debug1: Authentication

On Fri, 9 Jun 2023, Chris Rapier wrote: > Hi all, > > When a client requests dynamic remote forwarding with -R it delays forking > into the background. In ssh.c we see > > if (options.fork_after_authentication) { > if (options.exit_on_forward_failure && > options.num_remote_forwards > 0) { > debug("deferring postauth fork until

https://bugzilla.mindrot.org/show_bug.cgi?id=3692 Bug ID: 3692 Summary: rekey.sh doesn't actually test different algorithms Product: Portable OpenSSH Version: 9.7p1 Hardware: Other OS: Linux Status: NEW Severity: enhancement Priority: P5 Component: Regression tests

OpenSSH 3.2.2 has just been released. It will be available from the mirrors listed at http://www.openssh.com/ shortly. OpenSSH is a 100% complete SSH protocol version 1.3, 1.5 and 2.0 implementation and includes sftp client and server support. We would like to thank the OpenSSH community for their continued support and encouragement. Security Changes: ================= - fixed buffer overflow

Dear all, while playing around with openssh-4.1p1 (trying to add AFS token forwarding in SSH-2), I noticed that agressive rekeying (as e.g. employed by regress/rekey.sh, rekeying every 16bytes) seems to disturb the various forwardings (X11, agent) set up at the beginning of the session. These do not trigger regression test errors, since the client does not ask for confirmation from the server for

I'm wondering why the ChaCha20 cipher rekeys so frequently. At speed I'm seeing rekeys every second or two. So I'm spending a large amount of time in the rekey process. From what I've read about ChaCha20 it shouldn't need to be rekeyed quite so frequently. Am I missing something obvious? Just curious more than anything else. Chris

https://bugzilla.mindrot.org/show_bug.cgi?id=2929 Bug ID: 2929 Summary: OpenSSH server should not send the SSH_MSG_EXT_INFO message after rekeying Product: Portable OpenSSH Version: 7.7p1 Hardware: Other OS: Linux Status: NEW Severity: enhancement Priority: P5

Hi, mancha and me debugged a problem with OpenSSH 7.3p1 that was reported on the #openssh freenode channel. Symptoms were that this message was popping on the console during a busy X11 session: kex protocol error: type 7 seq 1234 I managed to reproduce the problem, it is related to the SSH_EXT_INFO packet that is send by the server every time it is sending an SSH_NEWKEYS packet, hence after

Server host config: Slackware 8.0 (custom boot scripts) glibc-2.2.3 gcc-2.95.3 Linux-2.4.18 Client host config: (same as server) Symptom: session disconnects with no message to client: ============================================================================= phil at antares:/home/phil 153> ssh -V OpenSSH_3.1p1, SSH protocols 1.5/2.0, OpenSSL 0x0090603f phil at antares:/home/phil 154>

Using OpenSSH_8.3p1 I had an open (working) connection to some other box; after a bit of inactivity, some device in the middle seems to have forgotten about the TCP connection (NAT) and broke it. I've got an EscapeChar defined, though; so first I tried to send a BREAK and, when that didn't help (TCP already gone, packets get lost!), I tried (just out of curiosity) a Rekey. Now I can see

Hello, everybody. I have encountered some strange situations that are driving me crazy. I have 2 DCs which using sernet samba, version 4.7.6. and I use a samba version 4.6.2 as a domain member for file sharing in CentOS7.4. The domain member works well as a file server, but When I login to that domain member using AD authtication. Sometimes, It works OK too, but sometime , I can't login that

https://bugzilla.mindrot.org/show_bug.cgi?id=2252 Bug ID: 2252 Summary: RekeyLimit breaks ClientAlive Product: Portable OpenSSH Version: 6.6p1 Hardware: All OS: All Status: NEW Severity: normal Priority: P5 Component: sshd Assignee: unassigned-bugs at mindrot.org

> Portable OpenSSH is also available via [...] Github: https://github.com/openssh/openssh-portable > > Running the regression tests supplied with Portable OpenSSH does not require installation and is a simply: > > $ ./configure && make tests I was going to try this on Kali Linux (latest version), but ran into trouble right away. No "configure" script exists

Hi all, When a client requests dynamic remote forwarding with -R it delays forking into the background. In ssh.c we see if (options.fork_after_authentication) { if (options.exit_on_forward_failure && options.num_remote_forwards > 0) { debug("deferring postauth fork until remote forward " "confirmation received");