Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Use this forum if you have installed hMailServer and want to ask a question related to a production release of hMailServer. Before posting, please read the troubleshooting guide. A large part of all reported issues are already described in detail here.
Post Reply
User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-13 19:55

I am using Version 5.6.8-B2574.

In the Logs I'm noticing a peculiar behavior.
1. Sending Email Server to hMailServer issues a STARTTLS.
2. hMailServer responds with 220 Ready to start TLS
3. Get Performing SSL/TLS handshake.
4. Get TCP Connection - TLS/SSL failed with also a message No shared cipher.
5. Then Ending session.
6. Same server and IP Address then reattempts sending to hMailServer immediately afterwards.
7. SSL/TLS handshake is not attempted.
8. Then receive Mail From and RCPT To commands.
9. Sending Server completes send successfully to hMailServer.

This behavior comes from different servers which don't appear to be related to each other (Government versus a Bank). This doesn't seem to happen all the time. I have gotten a No shared cipher message many times in the past but I never noticed that it would be followed by a reattempt without attempting to do the SSL/TLS Handshake on the reattempt. The other No shared cipher messages appeared to be a server attempting to find out what TLS Versions I was accepting, etc.

Does anyone know why I am seeing what appears to be a peculiar behavior?

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-13 21:04

As far as i know this is the intended behavior, it's basically like you say it:
  1. Use TLS if supported and ciphers between client and server correlate, if not:
  2. fallback to unencrypted SMTP protocol
So you probably have a (too) strict list of ciphers allowed,
Same would happen if the sending server for example is still using TLSv1.0 or TLSv1.1 whereas your server for example only accepts TLSv1.2 and TLSv1.3
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-13 21:33

RvdH wrote:
2021-10-13 21:04
As far as i know this is the intended behavior, it's basically like you say it:
  1. Use TLS if supported and ciphers between client and server correlate, if not:
  2. fallback to unencrypted SMTP protocol
So you probably have a (too) strict list of ciphers allowed, or the sending server for example is still using TLSv1.0 or TLSv1.1 whereas your server for example only accepts TLSv1.2 and TLSv1.3
Don't think this is the situation. I have seen in my Log Entries in the past where the situation you describe occurs and it is not the same as what is happening here.

The fallback to unencrypted SMTP Protocol when this happens is in the same session from what I have seen in the past. In this situation, when the Sending Email Server accepts the SMTP re-connection and successfully accepts the message, the Sending Email Server is on a newly created separate Session different from the first and it just doesn't even attempt to do an SSL/TLS Handshake.

One of the key differences in this situation is that the 'No shared cipher' session is ended and a completely new session where the sending Email Server starts the transaction over from the beginning and then succeesds because apparently it doesn't attempt to negotiate the Encryption Protocols (TLS/SSL).

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-13 21:38

jim.bus wrote:
2021-10-13 21:33
Don't think this is the situation.
i do, unless you can convince me otherwise ;)

Basically it comes down to capabilities of the client/sending server, and what that client/server is configured to do if there are no shared ciphers.
There is no way to force the sending server/client to retry using TLS (with another cipher) except by using StartTLS required...but you normally won't do that on port 25 for example...as you might be missing a lot of mails then
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-13 22:11

RvdH wrote:
2021-10-13 21:38
jim.bus wrote:
2021-10-13 21:33
Don't think this is the situation.
i do, unless you can convince me otherwise ;)

Basically it comes down to capabilities of the client/sending server, and what that client/server is configured to do if there are no shared ciphers.
There is no way to force the sending server/client to retry using TLS (with another cipher) except by using StartTLS required...but you normally won't do that on port 25 for example...as you might be missing a lot of mails then
I had been thinking along the lines of what you wrote. hMailServer however in its connections to Receiving Server will fallback to an unencrypted connection if 'optional' is selected in the Protocol specification such as 'StartTLS Optional'. But your statement about the 'StartTLS Optional' made me think about the 'Optional' parameter and that is probably what is happening as you state. However, to be clear, I am using the default Ciphers (I don't specify any particular Ciphers in hMailServer). So, the Default Ciphers are as you wrote probably too 'strict'.

I do know, for instance, that not all Email Servers such as Bank Of America in the US do not follow the RFCs. Bank Of America for instance doesn't check for Backup Email Servers (higer preference number MX Records) when when the Primary Email Server cannot be reached. So, it doesn't surprise me that a Sending Email Server may implement fallback in the manner where it starts the transaction all over again without using Encryption.

So, thanks for supplying a probably correct reason for this observed behavior.

mikedibella
Senior user
Senior user
Posts: 570
Joined: 2016-12-08 02:21

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by mikedibella » 2021-10-13 22:12

Try calling back to the suspect IP on port 25 to see if you can identify the implementation by the welcome message. You can they research the implementation to confirm this behavior variant is expected.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-13 22:22

viewtopic.php?t=27870

Various TLS handshake errors in my logs

Message: unknown protocol
Message: version too low
Message: unsupported protocol
Message: inappropriate fallback
Message: no shared cipher
Message: no suitable key share


I don't know for sure if the default ciphers changed when TLSv1.3 support was added, but you could play around with those

I currently use this, TLSv1.2 and TLSv1.3 only

Code: Select all

TLS13-AES-256-GCM-SHA384:TLS13-AES-128-GCM-SHA256:TLS13-AES-128-CCM-8-SHA256:TLS13-AES-128-CCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA38:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256;
But this is valid to if you only allow TLSv1.2 and TLSv1.3 (less strict)

Code: Select all

HIGH:!TLSv1:!SSLv3;
https://www.openssl.org/docs/man1.1.1/man1/ciphers.html
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-13 22:46

mikedibella wrote:
2021-10-13 22:12
Try calling back to the suspect IP on port 25 to see if you can identify the implementation by the welcome message. You can they research the implementation to confirm this behavior variant is expected.
One of the suspect IP Address is the server which services the US Congress House of Representatives members email. They haven't a clue as to how things work and it would be more trouble than its worth to try to find a contact in their Support department though I could try sending something to Postmaster. To give you an idea of what I mean. Being a US Government email Server you would think they would use the highest level of Encryption Protocol TLS 1.3 but instead they use TLS 1.2.

I also just noticed that they must either have changed to a different server or they used to negotiate to TLS 1.2 and now they don't seem to negotiate to anything or their Ciphers are more restrictive. So, it looks like something changed recently. Probably during September from what I've seen so far in my Logs.

Now again along the lines you just posted about, I just recently moved to 5.6.8-B2574 and this build wasn't released until I believe 10-3-21. As I stated I didn't see this 'No shared ciphers' message until it looks like in October and I didn't upgrade to 5.6.8-B2574 until some time after 10-3-21. I've been using version 5.6.8 for quite a while and didn't have this 'No shared ciphers' message until it looks like after I went to 5.6.8-B2574. This makes me wonder if something changed with the Ciphers for 5.6.8-B2574. Could this be a possible bug/omission with the ciphers of 5.6.8-B2574.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-13 22:57

Hard to tell, can be a change on their end or a change in 5.6.8-B2574 (which is basically only OpenSSL 1.1.1l)

I can only assume OpenSSL 1.1.1l is build using instructions listed here: https://github.com/hmailserver/hmailserver/tree/5.6.8
But if you wan't to be sure you really should ask martin, eg: for all i know he accidentally left out the enable-weak-ssl-ciphers command that used to be in there (or build your own OpenSSL 1.1.1l using instructions above)
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-13 23:06

RvdH wrote:
2021-10-13 22:57
Hard to tell, can be a change on their end or a change in 5.6.8-B2574 (which is basically only OpenSSL 1.1.1l)

I can only assume OpenSSL 1.1.1l is build using instructions listed here: https://github.com/hmailserver/hmailserver/tree/5.6.8
But if you wan't to be sure you really should ask martin, eg: for all i know he accidentally left out the enable-weak-ssl-ciphers command that used to be in there (or build your own OpenSSL 1.1.1l using instructions above)
I made a subsequent post after my last post which didn't seem to get picked up in the Forum. But I basically suggested that possibly the Ciphers for OpenSSL 1.1.1l may be more restrictive.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-13 23:11

jim.bus wrote:
2021-10-13 23:06
I made a subsequent post after my last post which didn't seem to get picked up in the Forum. But I basically suggested that possibly the Ciphers for OpenSSL 1.1.1l may be more restrictive.
No mention of something like that in OpenSSL 1.1.1l changelog, https://www.openssl.org/news/secadv/20210824.txt
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
mattg
Moderator
Moderator
Posts: 21645
Joined: 2007-06-14 05:12
Location: 'The Outback' Australia

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by mattg » 2021-10-14 00:50

jim.bus wrote:
2021-10-13 21:33
The fallback to unencrypted SMTP Protocol when this happens is in the same session from what I have seen in the past.
I've never seen that

I've only ever seen multiple sessions, one (often many, sometimes over days) with TLS attempts, and then an unencrypted one
ATO (Australian Tax Office) newsletter springs to mind

What are your current ciphers?
Just 'cause I link to a page and say little else doesn't mean I am not being nice.
https://www.hmailserver.com/documentation

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-14 01:37

mattg wrote:
2021-10-14 00:50
jim.bus wrote:
2021-10-13 21:33
The fallback to unencrypted SMTP Protocol when this happens is in the same session from what I have seen in the past.
I've never seen that

I've only ever seen multiple sessions, one (often many, sometimes over days) with TLS attempts, and then an unencrypted one
ATO (Australian Tax Office) newsletter springs to mind

What are your current ciphers?
Maybe I'm thinking of something else because I don't recall many instances of where a TLS/SSL protocol isn't agreed upon except for obvious phishing attempts from SPAMMERS and they just stop when they fail.

I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.

Here is a snippet of my Log Entries with sensitive IP Addresses and User IDs masked. The first connection, session 24 failed but the second connection, session 26 succeeded. If this is normal behavior then I'll stand corrected.

"DEBUG" 4636 "2021-10-13 09:10:51.070" "Creating session 26"
"TCPIP" 4636 "2021-10-13 09:10:51.070" "TCP - 143.228.42.33 connected to 192.168.x.x:25."
"DEBUG" 4636 "2021-10-13 09:10:51.086" "TCP connection started for session 24"
"SMTPD" 4636 24 "2021-10-13 09:10:51.086" "143.228.42.33" "SENT: 220 Pleased To Meet You"
"SMTPD" 4608 24 "2021-10-13 09:10:51.181" "143.228.42.33" "RECEIVED: EHLO serg-bulk2-a.house.gov"
"SMTPD" 4608 24 "2021-10-13 09:10:51.181" "143.228.42.33" "SENT: 250-mail.example.com[nl]250-SIZE 25600000[nl]250-STARTTLS[nl]250 HELP"
"SMTPD" 4636 24 "2021-10-13 09:10:51.307" "143.228.42.33" "RECEIVED: STARTTLS"
"SMTPD" 4636 24 "2021-10-13 09:10:51.307" "143.228.42.33" "SENT: 220 Ready to start TLS"
"DEBUG" 4608 "2021-10-13 09:10:51.307" "Performing SSL/TLS handshake for session 24. Verify certificate: False"
"TCPIP" 4604 "2021-10-13 09:10:51.400" "TCPConnection - TLS/SSL handshake failed. Session Id: 24, Remote IP: 143.228.42.33, Error code: 337092801, Message: no shared cipher"
"DEBUG" 4604 "2021-10-13 09:10:51.400" "Ending session 24"
"DEBUG" 4636 "2021-10-13 09:10:51.666" "Creating session 27"
"TCPIP" 4636 "2021-10-13 09:10:51.682" "TCP - 143.228.42.33 connected to 192.168.x.x:25."
"DEBUG" 4636 "2021-10-13 09:10:51.682" "TCP connection started for session 26"
"SMTPD" 4636 26 "2021-10-13 09:10:51.682" "143.228.42.33" "SENT: 220 Pleased To Meet You"
"SMTPD" 4604 26 "2021-10-13 09:10:51.775" "143.228.42.33" "RECEIVED: EHLO serg-bulk2-a.house.gov"
"SMTPD" 4604 26 "2021-10-13 09:10:51.775" "143.228.42.33" "SENT: 250-mail.jbsbtech.com[nl]250-SIZE 25600000[nl]250-STARTTLS[nl]250 HELP"
"SMTPD" 4520 26 "2021-10-13 09:10:51.885" "143.228.42.33" "RECEIVED: MAIL From:<Congressman.DeSaulnier@mail.house.gov> SIZE=28439"
"TCPIP" 4520 "2021-10-13 09:10:51.979" "DNS lookup: 33.42.228.143.zen.spamhaus.org, 0 addresses found: (none), Match: False"
"TCPIP" 4520 "2021-10-13 09:10:52.025" "DNS lookup: 33.42.228.143.bl.spamcop.net, 0 addresses found: (none), Match: False"
"DEBUG" 4520 "2021-10-13 09:10:52.041" "Spam test: SpamTestDNSBlackLists, Score: 0"
"DEBUG" 4520 "2021-10-13 09:10:52.104" "Spam test: SpamTestHeloHost, Score: 2"
"DEBUG" 4520 "2021-10-13 09:10:52.198" "Spam test: SpamTestSPF, Score: 0"
"DEBUG" 4520 "2021-10-13 09:10:52.198" "Total spam score: 2"
"SMTPD" 4520 26 "2021-10-13 09:10:52.261" "143.228.42.33" "SENT: 250 OK"
"SMTPD" 4636 26 "2021-10-13 09:10:52.355" "143.228.42.33" "RECEIVED: RCPT To:<user@example.com>"
"SMTPD" 4636 26 "2021-10-13 09:10:52.386" "143.228.42.33" "SENT: 250 OK"
"SMTPD" 4604 26 "2021-10-13 09:10:52.481" "143.228.42.33" "RECEIVED: DATA"
"SMTPD" 4604 26 "2021-10-13 09:10:52.481" "143.228.42.33" "SENT: 354 OK, send."
"DEBUG" 4608 "2021-10-13 09:10:52.731" "Adding task AsynchronousTask to work queue Asynchronous task queue"
"DEBUG" 2972 "2021-10-13 09:10:52.731" "Executing task AsynchronousTask in work queue Asynchronous task queue"
"DEBUG" 2972 "2021-10-13 09:10:52.731" "SURBL: Execute"
"

User avatar
mattg
Moderator
Moderator
Posts: 21645
Joined: 2007-06-14 05:12
Location: 'The Outback' Australia

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by mattg » 2021-10-14 04:08

jim.bus wrote:
2021-10-14 01:37
I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.
That is a problem

This is my current list (TLSv1.2 and TLSv1,3 only accepted on my system

Code: Select all

TLS13-AES-256-GCM-SHA384:TLS13-AES-128-GCM-SHA256:TLS13-AES-128-CCM-8-SHA256:TLS13-AES-128-CCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA38:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256
I use this periodically to update my ciphers
https://ssl-config.mozilla.org/

Use 'Postfix' for hMailserver
Just 'cause I link to a page and say little else doesn't mean I am not being nice.
https://www.hmailserver.com/documentation

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-14 07:29

mattg wrote:
2021-10-14 04:08
jim.bus wrote:
2021-10-14 01:37
I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.
That is a problem

This is my current list (TLSv1.2 and TLSv1,3 only accepted on my system

Code: Select all

TLS13-AES-256-GCM-SHA384:TLS13-AES-128-GCM-SHA256:TLS13-AES-128-CCM-8-SHA256:TLS13-AES-128-CCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA38:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256
I use this periodically to update my ciphers
https://ssl-config.mozilla.org/

Use 'Postfix' for hMailserver
I did some more research and unfortunately I deleted last months logs earlier this month so I can't look in them but so far in my October Logs, I find the only sending servers that communicated with me which seem to show this problem are sending servers that are either the US House Of Representatives servers or Financial Institution Servers. Furthermore this issue seems to not have developed with 5.6.8-B2574 as I found this issue occurring in my October Logs before I believe I installed 5.6.8-B2574.

tunis
Senior user
Senior user
Posts: 295
Joined: 2015-01-05 20:22
Location: Sweden

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by tunis » 2021-10-14 09:32

I looked at my logs and I see TLS 1.3 presents different and are not in my cipher list.

Code: Select all

TLS_AES_256_GCM_SHA384
TLS_AES_128_GCM_SHA256
On all adder TLS it's logged as cipher list format.

Code: Select all

ECDHE-RSA-AES256-GCM-SHA384
Does TLS 1.3 work without cipher list or has OpenSSL an internal list?

I have not AES-128-GCM-SHA256 or AES-256-GCM-SHA384 in my list.
HMS 5.6.8 B2534.28 on Windows Server 2019 Core VM.
HMS 5.6.8 B2538.30 on Windows Server 2016 Core VM.
HMS 5.6.7 B2425.16 on Windows Server 2012 R2 Core VM.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 09:52

jim.bus wrote:
2021-10-14 01:37
I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.
I don't think this is empty by default, no?

C:\Program Files (x86)\hMailServer\DBScripts\CreateTablesMYSQL.sql

Code: Select all

insert into hm_settings (settingname, settingstring, settinginteger) values ('SslCipherList', 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:ECDHE-RSA-RC4-SHA:ECDHE-ECDSA-RC4-SHA:AES128:AES256:RC4-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK;', 0);

@tunis, viewtopic.php?p=213775#p213775
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-14 11:16

RvdH wrote:
2021-10-14 09:52
jim.bus wrote:
2021-10-14 01:37
I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.
I don't think this is empty by default, no?

C:\Program Files (x86)\hMailServer\DBScripts\CreateTablesMYSQL.sql

Code: Select all

insert into hm_settings (settingname, settingstring, settinginteger) values ('SslCipherList', 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:ECDHE-RSA-RC4-SHA:ECDHE-ECDSA-RC4-SHA:AES128:AES256:RC4-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK;', 0);

@tunis, viewtopic.php?p=213775#p213775
I have been using hMailServer for 10 years and the SSL/TLS Ciphers Entry has always been empty by default. But I still see in my Log entries today where Sending Email Servers do agree on a Cipher with hMailServer.

Also the hMailServer Documentation for SSL/TLS does indicate there is a Default Cipher. See the excerpt from the Help Documentation below:

SSLv3 or TLS

During SSL/TLS handshake, the peers will agree on what cryptographic protocol and cipher to use. This is based on the implemented support in the two peers, and the configuration of them. For example, if a client which only supports SSLv3 connects to a server which supports both SSLv3 and TLS1.1, then SSLv3 will be used. If there is no protocol support in common, the handshake will fail.

In hMailServer, it's possible to override the default SSL/TLS cipher list. To do this, open hMailServer Administrator and navigate to Settings -> Advanced -> Security. In the SSL/TLS ciphers text box, you can enter an OpenSSL cipher list.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 11:23

That doesn't change the fact the cipher list should not be empty, as a default installation or upgrade should have populated this (so perhaps you haven't followed the proper upgrade path while updating)

C:\Program Files (x86)\hMailServer\DBScripts\CreateTablesMYSQL.sql

Code: Select all

insert into hm_settings (settingname, settingstring, settinginteger) values ('SslCipherList', 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:ECDHE-RSA-RC4-SHA:ECDHE-ECDSA-RC4-SHA:AES128:AES256:RC4-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK;', 0);

C:\Program Files (x86)\hMailServer\DBScripts\Upgrade5502to5600MySQL.sql

Code: Select all

UPDATE hm_settings SET SettingString = 'ECDHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES256-GCM-SHA384:DHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:kEDH+AESGCM:ECDHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES256-SHA384:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA:ECDHE-ECDSA-AES256-SHA:DHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA:DHE-DSS-AES128-SHA256:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA:DHE-RSA-AES256-SHA:AES128-GCM-SHA256:AES256-GCM-SHA384:ECDHE-RSA-RC4-SHA:ECDHE-ECDSA-RC4-SHA:AES128:AES256:RC4-SHA:HIGH:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK;' WHERE SettingName = 'SslCipherList' AND SettingString = '';

update hm_dbversion set value = 5600;
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 11:39

mattg wrote:
2021-10-14 04:08
jim.bus wrote:
2021-10-14 01:37
I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.
That is a problem

This is my current list (TLSv1.2 and TLSv1,3 only accepted on my system

Code: Select all

TLS13-AES-256-GCM-SHA384:TLS13-AES-128-GCM-SHA256:TLS13-AES-128-CCM-8-SHA256:TLS13-AES-128-CCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA38:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256
I use this periodically to update my ciphers
https://ssl-config.mozilla.org/

Use 'Postfix' for hMailserver
Trying to digest what that configurator does....you added the TLSv1.3 ciphers yourself? As that tool doesn't seem to include them by default :?: :!:

I do log TLS entries, my stats for Oct (date, CipherVersion, CipherName, CipherBits, Hits)

Code: Select all

2021-10-14 11:36:11	TLSv1.2	DHE-RSA-AES128-GCM-SHA256	128	309
2021-09-21 15:59:50	TLSv1.2	DHE-RSA-AES128-SHA256	128	1
2021-10-14 11:34:26	TLSv1.2	ECDHE-RSA-AES128-GCM-SHA256	128	6589
2021-10-14 08:46:00	TLSv1.2	ECDHE-RSA-AES128-SHA256	128	193
2021-10-14 11:34:50	TLSv1.3	TLS_AES_256_GCM_SHA384	256	4731
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-14 11:53

RvdH wrote:
2021-10-14 11:39
mattg wrote:
2021-10-14 04:08
jim.bus wrote:
2021-10-14 01:37
I do not specify any Ciphers explicitly. So, any Ciphers are whatever hMailServer uses as default. On hMailAdmin> SSL/TLS the Ciphers entry is empty.
That is a problem

This is my current list (TLSv1.2 and TLSv1,3 only accepted on my system

Code: Select all

TLS13-AES-256-GCM-SHA384:TLS13-AES-128-GCM-SHA256:TLS13-AES-128-CCM-8-SHA256:TLS13-AES-128-CCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA38:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256
I use this periodically to update my ciphers
https://ssl-config.mozilla.org/

Use 'Postfix' for hMailserver
Trying to digest what that configurator does....you added the TLSv1.3 ciphers yourself? As that tool doesn't seem to include them by default :?: :!:

I do log TLS entries, my stats for Oct (date, CipherVersion, CipherName, CipherBits, Hits)

Code: Select all

2021-10-14 11:36:11	TLSv1.2	DHE-RSA-AES128-GCM-SHA256	128	309
2021-09-21 15:59:50	TLSv1.2	DHE-RSA-AES128-SHA256	128	1
2021-10-14 11:34:26	TLSv1.2	ECDHE-RSA-AES128-GCM-SHA256	128	6589
2021-10-14 08:46:00	TLSv1.2	ECDHE-RSA-AES128-SHA256	128	193
2021-10-14 11:34:50	TLSv1.3	TLS_AES_256_GCM_SHA384	256	4731
The Forum software frequently wipes out Replies I am in the process of Posting when somebody (as you did) makes a Posting before I complete my Reply so I'm not going to retype everything again as it is too much retyping.

However, I will summarize to say that the Text of the Documentation also doesn't say that the cipher entry should be populated and can be construed to imply that the cipher entry is empty because it states you can enter a cipher list.

Admittedly like a lot of the Documetation is, the Documentation is vague at times and doesn't state things in great detail. I can only relate my experience with hMailServer over my 10 years of using it to say that my installations of hMailServer have never populated the Cipher entry and yet as I see today, hMailServer manages to agree to a shared cipher with a Remote Server when one is available. This is consistent with the 'vague' wording of the Documentation I copied out from the Documentation. So, I have seen evidence over 10 years that there is a Default cipher and that the Cipher entry by default is not populated on the SSL/TLS cipher entry.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 12:30

jim.bus wrote:
2021-10-14 11:53
The Forum software frequently wipes out Replies I am in the process of Posting when somebody (as you did) makes a Posting before I complete my Reply so I'm not going to retype everything again as it is too much retyping.
You get a notification if there is been a posting since last reply, and you have to confirm once again you still like to reply
Last edited by RvdH on 2021-10-14 12:44, edited 1 time in total.
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

palinka
Senior user
Senior user
Posts: 3008
Joined: 2017-09-12 17:57

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by palinka » 2021-10-14 12:30

jim.bus wrote:
2021-10-14 11:16
I have been using hMailServer for 10 years and the SSL/TLS Ciphers Entry has always been empty by default.
New installs should contain the default ciphers. If you removed them at one point and upgraded or restored a backup (or series of upgrades/restores) then they wouldn't be present because you copied in your existing settings that contain a blank entry for ciphers.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 12:34

jim.bus wrote:
2021-10-14 11:53
However, I will summarize to say that the Text of the Documentation also doesn't say that the cipher entry should be populated and can be construed to imply that the cipher entry is empty because it states you can enter a cipher list.

Admittedly like a lot of the Documetation is, the Documentation is vague at times and doesn't state things in great detail. I can only relate my experience with hMailServer over my 10 years of using it to say that my installations of hMailServer have never populated the Cipher entry and yet as I see today, hMailServer manages to agree to a shared cipher with a Remote Server when one is available. This is consistent with the 'vague' wording of the Documentation I copied out from the Documentation. So, I have seen evidence over 10 years that there is a Default cipher and that the Cipher entry by default is not populated on the SSL/TLS cipher entry.
But HMS by default has a populated cipher list....and you say you have none
You think you might have a problem somewhere and see unexpected behavior...and the only thing i notice your HMS instance settings differ from default settings (eg: lacking of cipher list)

Im just trying to help by narrow down what the cause of your issue could be

I'm not saying it is related at all, as i told earlier you (receiving server) can not control what the sending server/client has to do if a cipher fails, it's entirely up to the sending server/client
And yes, most common is this creates a new session, but once again, the (receiving server) can not control what the sending server/client has to do so if that server instance is configured to fallback immediately you could see what you are noticing in your logs
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

tunis
Senior user
Senior user
Posts: 295
Joined: 2015-01-05 20:22
Location: Sweden

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by tunis » 2021-10-14 13:12

I have looked at the doc page. https://www.openssl.org/docs/man1.1.1/man1/ciphers.html

I don't know if i have right, but it seems using CIPHER SUITE NAMES for the right TLS version if you don't have a cipher list.

If it does it can be different between OpenSSL version. In version 1.1.0 DES was remove from include default cipher.
HMS 5.6.8 B2534.28 on Windows Server 2019 Core VM.
HMS 5.6.8 B2538.30 on Windows Server 2016 Core VM.
HMS 5.6.7 B2425.16 on Windows Server 2012 R2 Core VM.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 13:58

tunis wrote:
2021-10-14 13:12
I have looked at the doc page. https://www.openssl.org/docs/man1.1.1/man1/ciphers.html

I don't know if i have right, but it seems using CIPHER SUITE NAMES for the right TLS version if you don't have a cipher list.

If it does it can be different between OpenSSL version. In version 1.1.0 DES was remove from include default cipher.
Yeah, i find that documentation extremely vague as well

Default OpenSSL 1.1.1l ciphers

input

Code: Select all

openssl ciphers
output

Code: Select all

TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES256-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES256-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES128-SHA:DHE-RSA-AES128-SHA:RSA-PSK-AES256-GCM-SHA384:DHE-PSK-AES256-GCM-SHA384:RSA-PSK-CHACHA20-POLY1305:DHE-PSK-CHACHA20-POLY1305:ECDHE-PSK-CHACHA20-POLY1305:AES256-GCM-SHA384:PSK-AES256-GCM-SHA384:PSK-CHACHA20-POLY1305:RSA-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-GCM-SHA256:AES128-GCM-SHA256:PSK-AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:ECDHE-PSK-AES256-CBC-SHA384:ECDHE-PSK-AES256-CBC-SHA:SRP-RSA-AES-256-CBC-SHA:SRP-AES-256-CBC-SHA:RSA-PSK-AES256-CBC-SHA384:DHE-PSK-AES256-CBC-SHA384:RSA-PSK-AES256-CBC-SHA:DHE-PSK-AES256-CBC-SHA:AES256-SHA:PSK-AES256-CBC-SHA384:PSK-AES256-CBC-SHA:ECDHE-PSK-AES128-CBC-SHA256:ECDHE-PSK-AES128-CBC-SHA:SRP-RSA-AES-128-CBC-SHA:SRP-AES-128-CBC-SHA:RSA-PSK-AES128-CBC-SHA256:DHE-PSK-AES128-CBC-SHA256:RSA-PSK-AES128-CBC-SHA:DHE-PSK-AES128-CBC-SHA:AES128-SHA:PSK-AES128-CBC-SHA256:PSK-AES128-CBC-SHA
The content of the default list is determined at compile time and normally corresponds to ALL:!COMPLEMENTOFDEFAULT:!eNULL
input

Code: Select all

openssl ciphers ALL:!COMPLEMENTOFDEFAULT:!eNULL
output

Code: Select all

TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES256-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA:ECDHE-RSA-AES256-SHA:DHE-RSA-AES256-SHA:ECDHE-ECDSA-AES128-SHA:ECDHE-RSA-AES128-SHA:DHE-RSA-AES128-SHA:RSA-PSK-AES256-GCM-SHA384:DHE-PSK-AES256-GCM-SHA384:RSA-PSK-CHACHA20-POLY1305:DHE-PSK-CHACHA20-POLY1305:ECDHE-PSK-CHACHA20-POLY1305:AES256-GCM-SHA384:PSK-AES256-GCM-SHA384:PSK-CHACHA20-POLY1305:RSA-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-GCM-SHA256:AES128-GCM-SHA256:PSK-AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256:ECDHE-PSK-AES256-CBC-SHA384:ECDHE-PSK-AES256-CBC-SHA:SRP-RSA-AES-256-CBC-SHA:SRP-AES-256-CBC-SHA:RSA-PSK-AES256-CBC-SHA384:DHE-PSK-AES256-CBC-SHA384:RSA-PSK-AES256-CBC-SHA:DHE-PSK-AES256-CBC-SHA:AES256-SHA:PSK-AES256-CBC-SHA384:PSK-AES256-CBC-SHA:ECDHE-PSK-AES128-CBC-SHA256:ECDHE-PSK-AES128-CBC-SHA:SRP-RSA-AES-128-CBC-SHA:SRP-AES-128-CBC-SHA:RSA-PSK-AES128-CBC-SHA256:DHE-PSK-AES128-CBC-SHA256:RSA-PSK-AES128-CBC-SHA:DHE-PSK-AES128-CBC-SHA:AES128-SHA:PSK-AES128-CBC-SHA256:PSK-AES128-CBC-SHA
So the quoted statement above seems true


input

Code: Select all

openssl ciphers HIGH:!TLSv1:!SSLv3;
output

Code: Select all

TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-DSS-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES256-CCM8:ECDHE-ECDSA-AES256-CCM:DHE-RSA-AES256-CCM8:DHE-RSA-AES256-CCM:ECDHE-ECDSA-ARIA256-GCM-SHA384:ECDHE-ARIA256-GCM-SHA384:DHE-DSS-ARIA256-GCM-SHA384:DHE-RSA-ARIA256-GCM-SHA384:ADH-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:DHE-DSS-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES128-CCM8:ECDHE-ECDSA-AES128-CCM:DHE-RSA-AES128-CCM8:DHE-RSA-AES128-CCM:ECDHE-ECDSA-ARIA128-GCM-SHA256:ECDHE-ARIA128-GCM-SHA256:DHE-DSS-ARIA128-GCM-SHA256:DHE-RSA-ARIA128-GCM-SHA256:ADH-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES256-SHA256:DHE-DSS-AES256-SHA256:ECDHE-ECDSA-CAMELLIA256-SHA384:ECDHE-RSA-CAMELLIA256-SHA384:DHE-RSA-CAMELLIA256-SHA256:DHE-DSS-CAMELLIA256-SHA256:ADH-AES256-SHA256:ADH-CAMELLIA256-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA256:DHE-DSS-AES128-SHA256:ECDHE-ECDSA-CAMELLIA128-SHA256:ECDHE-RSA-CAMELLIA128-SHA256:DHE-RSA-CAMELLIA128-SHA256:DHE-DSS-CAMELLIA128-SHA256:ADH-AES128-SHA256:ADH-CAMELLIA128-SHA256:RSA-PSK-AES256-GCM-SHA384:DHE-PSK-AES256-GCM-SHA384:RSA-PSK-CHACHA20-POLY1305:DHE-PSK-CHACHA20-POLY1305:ECDHE-PSK-CHACHA20-POLY1305:DHE-PSK-AES256-CCM8:DHE-PSK-AES256-CCM:RSA-PSK-ARIA256-GCM-SHA384:DHE-PSK-ARIA256-GCM-SHA384:AES256-GCM-SHA384:AES256-CCM8:AES256-CCM:ARIA256-GCM-SHA384:PSK-AES256-GCM-SHA384:PSK-CHACHA20-POLY1305:PSK-AES256-CCM8:PSK-AES256-CCM:PSK-ARIA256-GCM-SHA384:RSA-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-CCM8:DHE-PSK-AES128-CCM:RSA-PSK-ARIA128-GCM-SHA256:DHE-PSK-ARIA128-GCM-SHA256:AES128-GCM-SHA256:AES128-CCM8:AES128-CCM:ARIA128-GCM-SHA256:PSK-AES128-GCM-SHA256:PSK-AES128-CCM8:PSK-AES128-CCM:PSK-ARIA128-GCM-SHA256:AES256-SHA256:CAMELLIA256-SHA256:AES128-SHA256:CAMELLIA128-SHA256
That makes you think (as the 3nd command returned more ciphers) the default enabled ciphers are more strict as the HIGH:!TLSv1:!SSLv3; ciphers....and that was not what i suspected :!: :?:
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 14:24

This seems more like it for that matter....

input

Code: Select all

openssl ciphers HIGH:!TLSv1:!SSLv3:!COMPLEMENTOFDEFAULT:!eNULL
output

Code: Select all

TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384:DHE-RSA-AES256-GCM-SHA384:ECDHE-ECDSA-CHACHA20-POLY1305:ECDHE-RSA-CHACHA20-POLY1305:DHE-RSA-CHACHA20-POLY1305:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES256-SHA256:ECDHE-ECDSA-AES128-SHA256:ECDHE-RSA-AES128-SHA256:DHE-RSA-AES128-SHA256:RSA-PSK-AES256-GCM-SHA384:DHE-PSK-AES256-GCM-SHA384:RSA-PSK-CHACHA20-POLY1305:DHE-PSK-CHACHA20-POLY1305:ECDHE-PSK-CHACHA20-POLY1305:AES256-GCM-SHA384:PSK-AES256-GCM-SHA384:PSK-CHACHA20-POLY1305:RSA-PSK-AES128-GCM-SHA256:DHE-PSK-AES128-GCM-SHA256:AES128-GCM-SHA256:PSK-AES128-GCM-SHA256:AES256-SHA256:AES128-SHA256
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 15:11

tunis wrote:
2021-10-14 13:12
I have looked at the doc page. https://www.openssl.org/docs/man1.1.1/man1/ciphers.html

I don't know if i have right, but it seems using CIPHER SUITE NAMES for the right TLS version if you don't have a cipher list.

If it does it can be different between OpenSSL version. In version 1.1.0 DES was remove from include default cipher.
-ciphersuites val
Sets the list of TLSv1.3 ciphersuites. This list will be combined with any TLSv1.2 and below ciphersuites that have been configured. The format for this list is a simple colon (":") separated list of TLSv1.3 ciphersuite names. By default this value is:

Code: Select all

TLS_AES_256_GCM_SHA384:TLS_CHACHA20_POLY1305_SHA256:TLS_AES_128_GCM_SHA256
cipherlist
A cipher list of TLSv1.2 and below ciphersuites to convert to a cipher preference list. This list will be combined with any TLSv1.3 ciphersuites that have been configured. If it is not included then the default cipher list will be used. The format is described below.
ciphersuites => TLSv1.3, cipherlist =< TLS1.2
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-14 20:24

RvdH wrote:
2021-10-14 12:34
jim.bus wrote:
2021-10-14 11:53
However, I will summarize to say that the Text of the Documentation also doesn't say that the cipher entry should be populated and can be construed to imply that the cipher entry is empty because it states you can enter a cipher list.

Admittedly like a lot of the Documetation is, the Documentation is vague at times and doesn't state things in great detail. I can only relate my experience with hMailServer over my 10 years of using it to say that my installations of hMailServer have never populated the Cipher entry and yet as I see today, hMailServer manages to agree to a shared cipher with a Remote Server when one is available. This is consistent with the 'vague' wording of the Documentation I copied out from the Documentation. So, I have seen evidence over 10 years that there is a Default cipher and that the Cipher entry by default is not populated on the SSL/TLS cipher entry.
But HMS by default has a populated cipher list....and you say you have none
You think you might have a problem somewhere and see unexpected behavior...and the only thing i notice your HMS instance settings differ from default settings (eg: lacking of cipher list)

Im just trying to help by narrow down what the cause of your issue could be

I'm not saying it is related at all, as i told earlier you (receiving server) can not control what the sending server/client has to do if a cipher fails, it's entirely up to the sending server/client
And yes, most common is this creates a new session, but once again, the (receiving server) can not control what the sending server/client has to do so if that server instance is configured to fallback immediately you could see what you are noticing in your logs
I understand your point about behavior of Sending Email Server and accept that explanation as to Sending Email Server ending session and re-connecting to continue without Encryption Protocols.

However, I still contend that from my very first use of hMailServer over 10 years now, there never has been a populated SSL/TLS Cipher list in the Cipher entry area that we have been discussing yet hMailServer still negotiates a cipher with the Sending Email Server and nothing in the text of the Help Documentation states that the SSL/TLS cipher screen has it populated by default but that hMailServer still has a default cipher. Having a Default Cipher also doesn't mean that it is populated visibly in the Cipher entry list. The Help Documentation does indicate the Cipher entry area is for entering your own Cipher list and doesn't say that there will be a populated Default Cipher list in this entry. So, I have yet to see anywhere where the Cipher entry screen is stated that it will be populated with the Default Cipher.

I have never removed any Cipher lists from the Cipher entry area so I could never have kept wiping the 'Default Cipher list' out because it never was there in the first place. I have in the past done a clean install of hMailServer after my initial install the first time I ever used hMailServer and never had any Cipher list. But I still have obvisously a Default Cipher without the Cipher Entry area being populated because I see successful negotiations of Encryption protocols and ciphers in my hMailServer with a Sending Email Server. So, if the Cipher Entry is supposed to be populated by default, explain why my hMailServer installation still negotiates a successful cipher.

In any event, as I stated I now understand the points made by everyone about the Sending Email Server dictating how it will fall back to using no Encryption and no Ciphers and accept that is why I see this type of activity in my Logs. So, I consider my original concern has been cleared up for me.

I'm just debating why everyone believes the Cipher entry is supposed to be visibly populated by Default when the Help Documentation doesn't state that but does state there is a Default Cipher and to override the Default Cipher you make an entry into the Ciipher entry area of SSL/TLS entry of hMailAdmin. If you think about it, it also makes a little sense because if the Default Cipher were populated by Default then it would be very easy to accidentally alter it with invalid Ciphers or to delete a cipher. If no backups had been created, you would have to go to some effort to find the Default ciphers.

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-14 21:01

palinka wrote:
2021-10-14 12:30
jim.bus wrote:
2021-10-14 11:16
I have been using hMailServer for 10 years and the SSL/TLS Ciphers Entry has always been empty by default.
New installs should contain the default ciphers. If you removed them at one point and upgraded or restored a backup (or series of upgrades/restores) then they wouldn't be present because you copied in your existing settings that contain a blank entry for ciphers.
One thing I failed to acknowledge in my debate about whether the Cipher list entry is populated by default. If after my initial install 10 years ago, the cipher entry was defaulted to being populated then my restores from backup would of course wipe out that default population of the Cipher entry screen. However, that still doesn't account for why my hMailServer still negotiates a Cipher when the Cipher entry doesn't contain a default populated Cipher list.

After looking at tunis' link about OpenSSL, I renewed a suspicion that the default hMailServer Cipher may actually be a default Cipher in OpenSSL and not actually maintained with hMailServer code.

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 21:56

Agree, with the above
'openssl.exe ciphers' shows you the default cipherlist and ciphersuits enabled in OpenSSL (you can use HMS SSL/TLS cipher list to overrule the defaults!)

As we now know you have/had the default (builtin) SSL/TLS cipher enabled it makes me wonder more why a .gov domain can not find a shared cipher?
If you had a very restricted set of SSL/TLS ciphers enabled that would make sense...but now, not so much :wink:

Would a .gov domain server be so outdated so it only allow very weak ciphers? That sounds weird and not very plausible
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-14 22:24

OpenSSL builtin ciphers are least restrictive as you can see in output(s) below
sslscan mail.server.com:993

OpenSSL builtin ciphers (eg: blank cipherlist in HMS) (when only having TLSv1.2 and TLSv1.3 enabled in HMS)

Code: Select all

  SSL/TLS Protocols:
SSLv2     disabled
SSLv3     disabled
TLSv1.0   disabled
TLSv1.1   disabled
TLSv1.2   enabled
TLSv1.3   enabled

  TLS Fallback SCSV:
Server supports TLS Fallback SCSV

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:
TLSv1.3 not vulnerable to heartbleed
TLSv1.2 not vulnerable to heartbleed

  Supported Server Cipher(s):
Preferred TLSv1.3  256 bits  TLS_AES_256_GCM_SHA384        Curve P-256 DHE 256
Accepted  TLSv1.3  256 bits  TLS_CHACHA20_POLY1305_SHA256  Curve P-256 DHE 256
Accepted  TLSv1.3  128 bits  TLS_AES_128_GCM_SHA256        Curve P-256 DHE 256
Preferred TLSv1.2  256 bits  ECDHE-RSA-AES256-GCM-SHA384   Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-GCM-SHA384     DHE 2048 bits
Accepted  TLSv1.2  256 bits  ECDHE-RSA-CHACHA20-POLY1305   Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-CHACHA20-POLY1305     DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-GCM-SHA256   Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-GCM-SHA256     DHE 2048 bits
Accepted  TLSv1.2  256 bits  ECDHE-RSA-AES256-SHA384       Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-SHA256         DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-SHA256       Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-SHA256         DHE 2048 bits
Accepted  TLSv1.2  256 bits  ECDHE-RSA-AES256-SHA          Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-SHA            DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-SHA          Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-SHA            DHE 2048 bits
Accepted  TLSv1.2  256 bits  AES256-GCM-SHA384
Accepted  TLSv1.2  128 bits  AES128-GCM-SHA256
Accepted  TLSv1.2  256 bits  AES256-SHA256
Accepted  TLSv1.2  128 bits  AES128-SHA256
Accepted  TLSv1.2  256 bits  AES256-SHA
Accepted  TLSv1.2  128 bits  AES128-SHA

  Server Key Exchange Group(s):
TLSv1.3  128 bits  secp256r1 (NIST P-256)
TLSv1.2  128 bits  secp256r1 (NIST P-256)

  SSL Certificate:
Signature Algorithm: sha256WithRSAEncryption
RSA Key Strength:    3072

HIGH:!TLSv1:!SSLv3:!COMPLEMENTOFDEFAULT:!eNULL (when only having TLSv1.2 and TLSv1.3 enabled in HMS)

Code: Select all

  SSL/TLS Protocols:
SSLv2     disabled
SSLv3     disabled
TLSv1.0   disabled
TLSv1.1   disabled
TLSv1.2   enabled
TLSv1.3   enabled

  TLS Fallback SCSV:
Server supports TLS Fallback SCSV

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:
TLSv1.3 not vulnerable to heartbleed
TLSv1.2 not vulnerable to heartbleed

  Supported Server Cipher(s):
Preferred TLSv1.3  256 bits  TLS_AES_256_GCM_SHA384        Curve P-256 DHE 256
Accepted  TLSv1.3  256 bits  TLS_CHACHA20_POLY1305_SHA256  Curve P-256 DHE 256
Accepted  TLSv1.3  128 bits  TLS_AES_128_GCM_SHA256        Curve P-256 DHE 256
Preferred TLSv1.2  256 bits  ECDHE-RSA-AES256-GCM-SHA384   Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-GCM-SHA384     DHE 2048 bits
Accepted  TLSv1.2  256 bits  ECDHE-RSA-CHACHA20-POLY1305   Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-CHACHA20-POLY1305     DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-GCM-SHA256   Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-GCM-SHA256     DHE 2048 bits
Accepted  TLSv1.2  256 bits  ECDHE-RSA-AES256-SHA384       Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-SHA256         DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-SHA256       Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-SHA256         DHE 2048 bits
Accepted  TLSv1.2  256 bits  AES256-GCM-SHA384
Accepted  TLSv1.2  128 bits  AES128-GCM-SHA256
Accepted  TLSv1.2  256 bits  AES256-SHA256
Accepted  TLSv1.2  128 bits  AES128-SHA256

  Server Key Exchange Group(s):
TLSv1.3  128 bits  secp256r1 (NIST P-256)
TLSv1.2  128 bits  secp256r1 (NIST P-256)

  SSL Certificate:
Signature Algorithm: sha256WithRSAEncryption
RSA Key Strength:    3072
TLS13-AES-256-GCM-SHA384:TLS13-AES-128-GCM-SHA256:TLS13-AES-128-CCM-8-SHA256:TLS13-AES-128-CCM-SHA256:ECDHE-ECDSA-AES128-GCM-SHA256:ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-ECDSA-AES128-SHA256:ECDHE-ECDSA-AES256-SHA384:ECDHE-RSA-AES128-GCM-SHA256:ECDHE-RSA-AES256-GCM-SHA38:DHE-RSA-AES128-GCM-SHA256:DHE-RSA-AES256-GCM-SHA384:ECDHE-RSA-AES128-SHA256:ECDHE-RSA-AES256-SHA384:DHE-RSA-AES128-SHA256:DHE-RSA-AES256-SHA256 (when only having TLSv1.2 and TLSv1.3 enabled in HMS)

Code: Select all

  SSL/TLS Protocols:
SSLv2     disabled
SSLv3     disabled
TLSv1.0   disabled
TLSv1.1   disabled
TLSv1.2   enabled
TLSv1.3   enabled

  TLS Fallback SCSV:
Server supports TLS Fallback SCSV

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:
TLSv1.3 not vulnerable to heartbleed
TLSv1.2 not vulnerable to heartbleed

  Supported Server Cipher(s):
Preferred TLSv1.3  256 bits  TLS_AES_256_GCM_SHA384        Curve P-256 DHE 256
Accepted  TLSv1.3  256 bits  TLS_CHACHA20_POLY1305_SHA256  Curve P-256 DHE 256
Accepted  TLSv1.3  128 bits  TLS_AES_128_GCM_SHA256        Curve P-256 DHE 256
Preferred TLSv1.2  128 bits  ECDHE-RSA-AES128-GCM-SHA256   Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-GCM-SHA256     DHE 2048 bits
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-GCM-SHA384     DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-SHA256       Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  ECDHE-RSA-AES256-SHA384       Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-SHA256         DHE 2048 bits
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-SHA256         DHE 2048 bits

  Server Key Exchange Group(s):
TLSv1.3  128 bits  secp256r1 (NIST P-256)
TLSv1.2  128 bits  secp256r1 (NIST P-256)

  SSL Certificate:
Signature Algorithm: sha256WithRSAEncryption
RSA Key Strength:    3072
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
mattg
Moderator
Moderator
Posts: 21645
Joined: 2007-06-14 05:12
Location: 'The Outback' Australia

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by mattg » 2021-10-15 04:03

jim.bus wrote:
2021-10-14 21:01
However, that still doesn't account for why my hMailServer still negotiates a Cipher when the Cipher entry doesn't contain a default populated Cipher list.
Does it?

Your logs as shown just show failed connections
Just 'cause I link to a page and say little else doesn't mean I am not being nice.
https://www.hmailserver.com/documentation

User avatar
jim.bus
Senior user
Senior user
Posts: 790
Joined: 2011-05-28 11:49
Location: US

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by jim.bus » 2021-10-15 06:39

mattg wrote:
2021-10-15 04:03
jim.bus wrote:
2021-10-14 21:01
However, that still doesn't account for why my hMailServer still negotiates a Cipher when the Cipher entry doesn't contain a default populated Cipher list.
Does it?

Your logs as shown just show failed connections
As I was, at the time questioning, why I saw the behavior of the two sessions which you confirmed was what you had come to always see happening in your experience, I only showed you and example of where the two sessions occurred. I didn't show you the other Logs entries where Encryption Protocols and Cipher was agreed upon. See Example below. Incidentally, I'm almost sure I've seen the government server at one time agreeing on Encryption Protocols and Cipher but it isn't doing that now. That could very well be a problem with the government server. I'm sure I saw it using TLS 1.2 at one time not too long ago. I remember this as I would joke to people about how the government was using a less secure TLS instead of using TLS 1.3. This is an example which shows rvdh that our US Government isn't all that security conscious as they allow there Congressional members to use outdated security even though the email going through these servers may not be sensitive emails.

"TCPIP" 35388 "2021-10-14 07:00:52.048" "TCP - 149.72.27.102 connected to 192.168.x.x:25."
"DEBUG" 35388 "2021-10-14 07:00:52.048" "TCP connection started for session 17"
"SMTPD" 35388 17 "2021-10-14 07:00:52.048" "149.72.27.102" "SENT: 220 Pleased To Meet You"
"SMTPD" 33372 17 "2021-10-14 07:00:52.173" "149.72.27.102" "RECEIVED: EHLO o971.send.cyberlinkmember.com"
"SMTPD" 33372 17 "2021-10-14 07:00:52.173" "149.72.27.102" "SENT: 250-mail.example.com[nl]250-SIZE 25600000[nl]250-STARTTLS[nl]250 HELP"
"SMTPD" 35388 17 "2021-10-14 07:00:52.298" "149.72.27.102" "RECEIVED: STARTTLS"
"SMTPD" 35388 17 "2021-10-14 07:00:52.298" "149.72.27.102" "SENT: 220 Ready to start TLS"
"DEBUG" 32460 "2021-10-14 07:00:52.298" "Performing SSL/TLS handshake for session 17. Verify certificate: False"
"TCPIP" 35388 "2021-10-14 07:00:52.643" "TCPConnection - TLS/SSL handshake completed. Session Id: 17, Remote IP: 149.72.27.102, Version: TLSv1.3, Cipher: TLS_AES_128_GCM_SHA256, Bits: 128"
"SMTPD" 32460 17 "2021-10-14 07:00:52.659" "149.72.27.102" "RECEIVED: EHLO o971.send.cyberlinkmember.com"
"SMTPD" 32460 17 "2021-10-14 07:00:52.659" "149.72.27.102" "SENT: 250-mail.example.com[nl]250-SIZE 25600000[nl]250 HELP"
"SMTPD" 35388 17 "2021-10-14 07:00:52.847" "149.72.27.102" "RECEIVED: MAIL FROM:<bounces+20334379-216d-cyberlink.email=example.net@send.cyberlinkmember.com>"
"TCPIP" 35388 "2021-10-14 07:00:52.941" "DNS lookup: 102.27.72.149.zen.spamhaus.org, 0 addresses found: (none), Match: False"
"TCPIP" 35388 "2021-10-14 07:00:52.972" "DNS lookup: 102.27.72.149.bl.spamcop.net, 0 addresses found: (none), Match: False"
"DEBUG" 35388 "2021-10-14 07:00:52.972" "Spam test: SpamTestDNSBlackLists, Score: 0"
"DEBUG" 35388 "2021-10-14 07:00:53.035" "Spam test: SpamTestHeloHost, Score: 0"
"DEBUG" 35388 "2021-10-14 07:00:53.129" "Spam test: SpamTestSPF, Score: 0"
"DEBUG" 35388 "2021-10-14 07:00:53.129" "Total spam score: 0"

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-15 11:20

mattg wrote:
2021-10-15 04:03
jim.bus wrote:
2021-10-14 21:01
However, that still doesn't account for why my hMailServer still negotiates a Cipher when the Cipher entry doesn't contain a default populated Cipher list.
Does it?

Your logs as shown just show failed connections
Yup, see my post few post above "OpenSSL builtin ciphers (eg: blank cipherlist in HMS)", that is cipher list with no ciphers defined in HMS itself (only having TLSv1.2 and TLSv1.3 enabled)
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
SorenR
Senior user
Senior user
Posts: 4915
Joined: 2006-08-21 15:38
Location: Denmark

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by SorenR » 2021-10-15 14:35

RvdH wrote:
2021-10-15 11:20
mattg wrote:
2021-10-15 04:03
jim.bus wrote:
2021-10-14 21:01
However, that still doesn't account for why my hMailServer still negotiates a Cipher when the Cipher entry doesn't contain a default populated Cipher list.
Does it?

Your logs as shown just show failed connections
Yup, see my post few post above "OpenSSL builtin ciphers (eg: blank cipherlist in HMS)", that is cipher list with no ciphers defined in HMS itself (only having TLSv1.2 and TLSv1.3 enabled)
Partly off topic... I have a problem with sslscan ... SMTP:25 ... IMAP:143 complete without error. Both STARTTLS.

Code: Select all

Version: 2.0.10 Windows 64-bit (Mingw)
OpenSSL 1.1.1e-dev  xx XXX xxxx

Connected to 192.168.0.5

Testing SSL server 192.168.0.5 on port 25 using SNI name 192.168.0.5

  SSL/TLS Protocols:
SSLv2     disabled
SSLv3     disabled
TLSv1.0   disabled
TLSv1.1   disabled
TLSv1.2   enabled
TLSv1.3   enabled

  TLS Fallback SCSV:
Server supports TLS Fallback SCSV

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:
TLSv1.3 not vulnerable to heartbleed
TLSv1.2 not vulnerable to heartbleed

  Supported Server Cipher(s):
Preferred TLSv1.3  128 bits  TLS_AES_128_GCM_SHA256        Curve P-256 DHE 256
Accepted  TLSv1.3  256 bits  TLS_AES_256_GCM_SHA384        Curve P-256 DHE 256
Accepted  TLSv1.3  256 bits  TLS_CHACHA20_POLY1305_SHA256  Curve P-256 DHE 256
Preferred TLSv1.2  256 bits  DHE-RSA-AES256-GCM-SHA384     DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-GCM-SHA256   Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-GCM-SHA256     DHE 2048 bits
Accepted  TLSv1.2  256 bits  ECDHE-RSA-AES256-SHA384       Curve P-256 DHE 256
Accepted  TLSv1.2  256 bits  DHE-RSA-AES256-SHA256         DHE 2048 bits
Accepted  TLSv1.2  128 bits  ECDHE-RSA-AES128-SHA256       Curve P-256 DHE 256
Accepted  TLSv1.2  128 bits  DHE-RSA-AES128-SHA256         DHE 2048 bits

  Server Key Exchange Group(s):
TLSv1.3  128 bits  secp256r1 (NIST P-256)
ERROR: Unexpected EOF reading from 192.168.0.5:25
ERROR: Unexpected EOF reading from 192.168.0.5:25
SørenR.

Engineer (noun)
- I'm Not Arguing, I'm Just Explaining Why I'm Right

User avatar
RvdH
Senior user
Senior user
Posts: 1685
Joined: 2008-06-27 14:42
Location: Netherlands

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by RvdH » 2021-10-15 14:57

Mmm....
i'm even surprised you see that TLSv1.2 and TLSv1.3 is enabled....when i run sslscan on ports that are configured to use STARTTLS (Optional) i get nothing, eg:

Code: Select all

Version: 2.0.10 Windows 64-bit (Mingw)
OpenSSL 1.1.1e-dev  xx XXX xxxx

Connected to xxx.xxx.xxx.xxx

Testing SSL server mail.domain.nl on port 25 using SNI name mail.domain.nl

  SSL/TLS Protocols:
SSLv2     disabled
SSLv3     disabled
TLSv1.0   disabled
TLSv1.1   disabled
TLSv1.2   disabled
TLSv1.3   disabled

  TLS Fallback SCSV:
Connection failed - unable to determine TLS Fallback SCSV support

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:

  Supported Server Cipher(s):
Certificate information cannot be retrieved.

ERROR: Unexpected EOF reading from 192.168.0.5:25, IDS kicking in maybe :?: :!:

[edit]
Oops my bad....if i ran it like

Code: Select all

sslscan --starttls-smtp mail.domain.nl:25
it runs OK
CIDR to RegEx: d-fault.nl/CIDRtoRegEx
DNS Lookup: d-fault.nl/DNSTools
DNSBL Lookup: d-fault.nl/DNSBLLookup
GEOIP Lookup: d-fault.nl/GeoipLookup

User avatar
SorenR
Senior user
Senior user
Posts: 4915
Joined: 2006-08-21 15:38
Location: Denmark

Re: Log Entries Show Sending Server Fails TLS Handshake No Shared Cipher On Repeat Send TLS Not Used

Post by SorenR » 2021-10-15 15:49

RvdH wrote:
2021-10-15 14:57
Mmm....
i'm even surprised you see that TLSv1.2 and TLSv1.3 is enabled....when i run sslscan on ports that are configured to use STARTTLS (Optional) i get nothing, eg:

Code: Select all

Version: 2.0.10 Windows 64-bit (Mingw)
OpenSSL 1.1.1e-dev  xx XXX xxxx

Connected to xxx.xxx.xxx.xxx

Testing SSL server mail.domain.nl on port 25 using SNI name mail.domain.nl

  SSL/TLS Protocols:
SSLv2     disabled
SSLv3     disabled
TLSv1.0   disabled
TLSv1.1   disabled
TLSv1.2   disabled
TLSv1.3   disabled

  TLS Fallback SCSV:
Connection failed - unable to determine TLS Fallback SCSV support

  TLS renegotiation:
Session renegotiation not supported

  TLS Compression:
Compression disabled

  Heartbleed:

  Supported Server Cipher(s):
Certificate information cannot be retrieved.

ERROR: Unexpected EOF reading from 192.168.0.5:25, IDS kicking in maybe :?: :!:

[edit]
Oops my bad....if i ran it like

Code: Select all

sslscan --starttls-smtp mail.domain.nl:25
it runs OK
Local LAN is excluded from everything.
SørenR.

Engineer (noun)
- I'm Not Arguing, I'm Just Explaining Why I'm Right

Post Reply