search for: verifyhostkeydns

...s for a shell or emacs, but sometimes the session is in a curses application, or lost information while tailing a log, etc.). This gets uglier when making use of the fantastic ControlPersist options - seemingly logged out ssh session still blast the initial terminal with re-keying fingerprints. * VerifyHostKeyDNS=yes It seems VerifyHostKeyDNS=yes short-circuits VisualHostKey - it's neither displayed on initial connection, or on re-keying (good). So I have a funny setup: For hosts which have SSHFP records, I have set VerifyHostKeyDNS=yes and ineffectively set VisualHostKey=yes (never prints), and...

...n is made between when an SSHFP RR is missing from the result set (rather then being empty), which can lead to confusing error messages, (the "normal" warn_changed_key() blurb is emitted) e.g. when the presented host key and known hosts both match but there is no matching RR. Further, if VerifyHostKeyDNS and StrictHostKeyChecking are set, there is no prompting for confirmation if the connection should be allowed to proceed; I'm unsure if this is by design or not (as presented host key and known host key match), but I'd argue this violates POLA. Attached are two na?ve patches to portable (c...

...ot provide any other info so i cannot verify why this problem still exists in 5.6p1. Here is some output: karl at slap1:~$ cat /etc/resolv.conf domain corp.example.com search corp.example.com nameserver 10.13.0.133 options edns0 karl at slap1:~/openssh-5.6p1$ /nail/home/karl/ssh/bin/ssh -vvv -o VerifyHostKeyDNS=yes dsectest.corp.example.com OpenSSH_5.6p1, OpenSSL 0.9.8k 25 Mar 2009 <snip> debug2: ssh_connect: needpriv 0 debug1: Connecting to dsectest.corp.example.com [10.13.0.133] port 22. debug1: Connection established. <snip> debug1: Remote protocol version 2.0, remote software version OpenS...

http://bugzilla.mindrot.org/show_bug.cgi?id=1296 Summary: VerifyHostKeyDNS default domain Product: Portable OpenSSH Version: 4.3p2 Platform: ix86 OS/Version: Linux Status: NEW Severity: normal Priority: P2 Component: ssh AssignedTo: bitbucket at mindrot.org ReportedBy: dan at...

...internal domain, our main domain, and a helper domain with CNAMEs for several parters' hosts. We already implemented a tool to distribute SSHFP records over any domain a host is listed in (i.e. World address, DMZ address) to solve the multi-IP resp. multi-interface problem. But in this state VerifyHostKeyDNS is useless for us ;-( -- You are receiving this mail because: You are watching someone on the CC list of the bug. You are watching the assignee of the bug.

https://bugzilla.mindrot.org/show_bug.cgi?id=1296 Damien Miller <djm at mindrot.org> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |djm at mindrot.org Status|NEW |RESOLVED Resolution|

https://bugzilla.mindrot.org/show_bug.cgi?id=1296 Damien Miller <djm at mindrot.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|REOPENED |RESOLVED Resolution| |FIXED --- Comment #5 from Damien Miller <djm at

https://bugzilla.mindrot.org/show_bug.cgi?id=1608 Simon Deziel <simon at sdeziel.info> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |simon at sdeziel.info -- You are receiving this mail because: You are watching the assignee of the bug.

https://bugzilla.mindrot.org/show_bug.cgi?id=2501 Bug ID: 2501 Summary: VerifyHostKeyDNS & StrictHostKeyChecking Product: Portable OpenSSH Version: 7.1p1 Hardware: All OS: All Status: NEW Severity: normal Priority: P5 Component: ssh Assignee: unassigned-bugs at mindrot.org R...

Steps to reproduce: 1. Run a SSH server with default configuration and point a domain to it. 2. Add SSHFP record to the domain, but only for Ed25519 key. 3. Attempt to connect with VerifyHostKeyDNS set to yes, but the rest of settings set to defaults. 4. OpenSSH defaults to ECDSA instead of Ed25519 and refuses connection because there is no ECDSA fingerprint in SSHFP records. A stopgap solution is to either delete all keys except Ed25519 from the server or to always connect with HostKeyAlgor...

Please find attached file "configure.ac+dns.patch". This patch allow to compile current (30 Jun 2003) with options --with-dns on my platform. Output from "ssh -v -o VerifyHostKeyDNS=yes ..." follow: ... debug1: found 1 fingerprints in DNS debug1: matching host key fingerprint found in DNS ... -------------- next part -------------- An embedded and charset-unspecified text was scrubbed... Name: configure.ac+dns.patch Url: http://lists.mindrot.org/pipermail/openssh-unix-de...

Hello All, I have a client-server setup with about 100 nodes. We often install the OS and this results in change of host keys in our server. This necessiates the need to update all known_hosts files in the client machines. Im using the VerifyHostKeyDNS option in the client side where the DNS is updated with new finger print each time we change the host key. But still the SSH client verifies its known_hosts file even the DNS finger print matches. Is there any way to overcome clients local database checking if DNS finger print matches? What are...

...eived from the SSH server, then the key MUST be rejected rather than testing the alternative SHA-1 fingerprint. The current version of SSH does not conform this requirement. Attached patch fixes this issue. It can be tested using this command: $ ssh -vv -o HostKeyAlgorithms=ecdsa-sha2-nistp521 -o VerifyHostKeyDNS=yes sshfp-test-downgrade.oskarcz.net (The SSHFP records with SHA-256 digests for hostname sshfp-test-downgrade.oskarcz.net are intentionally altered.) -- You are receiving this mail because: You are watching the assignee of the bug.

Hello. I have an issue with SSHFP lookups using "VerifyHostKeyDNS=yes" and "options edns0" in /etc/resolv.conf (glib >= 2.6). getrrsetbyname() calls res_query() with a maximum buffer size of 65536. The glibc resolver truncates this value to 16 bits, reducing the query's advertised buffer size to 0. BIND appears to ignore it while Unbound...

...e common cases of non-smartcard keys and keys without destination constraints are unaffected. This problem was reported by Luci Stanescu. * ssh(1): Portable OpenSSH provides an implementation of the getrrsetbyname(3) function if the standard library does not provide it, for use by the VerifyHostKeyDNS feature. A specifically crafted DNS response could cause this function to perform an out-of-bounds read of adjacent stack data, but this condition does not appear to be exploitable beyond denial-of- service to the ssh(1) client. The getrrsetbyname(3) replacement is only included if...

On Sun, 4 Oct 2020, Christoph Anton Mitterer wrote: > On Sun, 2020-10-04 at 14:02 +1100, Damien Miller wrote: > > This is strictly no worse than continuing to use the old key, so I > > don't consider it a problem. > > Well but in reality it will lead to people never again replace their > key by proper means. Well, first I disagree that this method is improper. The

...mindrot.org> wrote: > > On Fri, 22 Feb 2019, Yegor Ievlev wrote: > > > Steps to reproduce: > > 1. Run a SSH server with default configuration and point a domain to it. > > 2. Add SSHFP record to the domain, but only for Ed25519 key. > > 3. Attempt to connect with VerifyHostKeyDNS set to yes, but the rest > > of settings set to defaults. > > 4. OpenSSH defaults to ECDSA instead of Ed25519 and refuses connection > > because there is no ECDSA fingerprint in SSHFP records. > > I'm not seeing the bug: typically you'd add SSHFP records for all >...

...at the SSHFP records), it fails even if there are two records with two different keys of the same algo for the same host. I will use examples from the original report[1] as they are still relevant # example with OpenSSH_8.9p1, OpenSSL 1.1.1m 14 Dec 2021 ssh -v -o HostKeyAlgorithms=ssh-ed25519 -o VerifyHostKeyDNS=yes ssh-service.einbeispiel.ch [...] debug1: verify_host_key_dns: failed SSHFP type 4 fptype 2 debug1: verify_host_key_dns: matched SSHFP type 4 fptype 2 debug1: mismatching host key fingerprint found in DNS [...] No matching host key fingerprint found in DNS. The bug report is filed for the firs...

hi, I recently committed an update of the code that handles lookup of SSHFP resource records in DNS. this code is now included by default, the old DNS and DNSSEC defines has been removed. for more information, read about VerifyHostKeyDNS in ssh_config(5) and check out README.dns. feedback would be appreciated, jakob

When connecting to a host that provides an ECDSA host key and the client has "VerifyHostKeyDNS" set to 'yes' or 'ask' SSH outputs a mysterious and undocumented message "Error calculating host key fingerprint." This error actually seems to be generated by verify_host_key_dns(const char *hostname, struct sockaddr *address, Key *hostkey, int *flags) in dns.c, but...