Show proper certificate information for incoming connections, too, and
not "peer did not present a certificate", regardless if the client sent
a certificate or not.
This change is for GnuTLS and similar to what was implemented in commit
for OpenSSL in "S2S-TLS/OpenSSL: Fix handling of certificate information
for incoming connections".
Without this, the S2S-TLS-Patch not even compiles with GnuTLS because
of the "new" GnuTLS certificate reload support implemented in commit
eead4a63 ("x509_cred_slot").
This includes simplifying cb_connserver_login_ssl() a bit, we do not
have to code for invalid state which was ruled out by an assert() and
therefore can get rid of the goto altogether (and don't log the same
error twice with different messages).
The verify callback in OpenSSL is called pretty early, and at that time
it is not possible yet to check which connection it belongs to, and some
connections may have relaxed requirements.
So always return success in the Verify_openssl() callback, and postpone
validation of the TLS session until starting the server handshake in
cb_connserver_login_ssl(), when we know which server this connection
belongs to and which options (like "SSLVerify") are in effect.
The code doing this was already present in cb_connserver_login_ssl(),
but this patch adds a more prominent comment to the function.
Show proper certificate information for incoming connections, too, and
not "peer did not present a certificate", regardless if the client sent
a certificate or not.
And free the client certificate structure "peer_cert" on incoming
connections as well!
Set the verification flags in the ConnSSL_SetVerifyProperties_openssl
function only, don't override them in ConnSSL_InitLibrary() afterwards.
No functional changes, now ConnSSL_SetVerifyProperties_openssl() sets
exactly the parameters which ConnSSL_InitLibrary() always overwrote ...
Setup host name verification even when the "SSLVerify" option is
disabled, because even then the peer can present a valid certificate and
validation would always(!) fail because of the missing host name
verification setup.
This patch provides code to validate the server certificate in
server links, defeating nasty man-in-the-middle attacks on server
links.
Features:
- Check whether the certificate is signed by a trusted certificate
authority (CA).
- Check the host name, including wildcard certificates and Subject
Alternative Names.
- Optionally check against a certificate revocation list (CRL).
- Implementation for both OpenSSL and GnuTLS linkage.
Left for another day:
- Parameterize the TLS parameter of an outbound connection. Currently,
it's hardcoded to disable all versions before TLSv1.1.
- Using certificate as CA-certificate. They work for GnuTLS only but
perhaps this should rather raise an error there, too.
- Optional OCSP checking.
- Checking client certificates. Code is there but this first needs some
consideration about the use cases. This could replace all other
authentication methods, for both client-server and server-server
connections.
This patch is based on a patch by Florian Westphal from 2009, which
implemented this for OpenSSL only:
From: Florian Westphal <fw@strlen.de>
Date: Mon, 18 May 2009 00:29:02 +0200
Subject: SSL/TLS: Add initial certificate support to OpenSSL backend
Commit message modified by Alex Barton.
Closes#120, "Server links using TLS/SSL need certificate validation".
Supersedes PR #8, "Options for verifying and requiring SSL client
certificates", which had (incomplete?) code for OpenSSL, no GnuTLS.
- Tweak some paragraphs and bring others more in line with texts on the
homepage ...
- Try to not duplicate information:
- Configuration is explained in doc/QuickStart.md;
- command line parameters are already better described in the
ngircd(8) manual page.
- Move all pointers to documentation to the README.md file, which is
directly shown in GitHub when browsing the repository, for example.
Correctly re-generate the "cloaked hostname" when removing the
"cloakhost" using an empty string by passing down NULL instead of the
empty string, which results in protocol violations (for example on
WHOIS).
The default value for the -nameopt option changed in OpenSSL 3.2 from
`oneline' to `utf8'. The `oneline' option also included a space around
the fields which is not the case for `utf8'. This means that
CN = my.first.domain.tld
changed to
CN=my.first.domain.tld
and is now longer recognized, leading to test failure.
This can be fixed by either going back to `oneline' or keeping `utf8'
and adding additionally `space_eq'. Anoter way would be to teach the
expect that the space is optional.
Add explicit -nameopt option with `utf8,space_eq' which is understood by
by OpenSSL 3.2 and earlier to make explicit. Remove the wildcard.
Signed-off-by: Sebastian Andrzej Siewior <sebastian@breakpoint.cc>
This makes sense because the package is build with SSL support enabled,
and we set and enable "CAFile" in commit ae9cfade -- which results in an
error when this is not in an enabled(!) [SSL] section ...
Move most information regarding configuring ngIRCd into the
doc/QuickStart.md document, only describe building and installing ngIRCd
in the INSTALL.md file. Don't duplicate content!
Add references where this makes sense.
No longer use a default built-in value for the "IncludeDir" directive
when a configuration file was explicitly specified on the command line
using "--config"/"-f": This way no default include directory is scanned
when a possibly non-default configuration file is used which
(intentionally) did not specify an "IncludeDir" directive.
With this patch you now can use "-f /dev/null" for checking all built-in
defaults, regardless of any local configuration files in the default
drop-in directory (which would have been read in until this change).
The "Info" option in the "[Global]" section is optional (so comment it
out in the sample configuration file) and set to the server software
name and its version when not set (so add this information to the sample
configuration file and the ngircd.conf(5) manual page).
The server "Name" in the "[Global]" section of the configuration file is
optional now: When not set (or empty), ngIRCd now tries to deduce a
valid IRC server name from the local host name ("node name"), possibly
adding a ".host" extension when the host name does not contain a dot
(".") which is required in an IRC server name ("ID").
This new behaviour, with all configuration parameters now being
optional, allows running ngIRCd without any configuration file at all.
Basically this is unnecessary, as Channel_UserModes() always returns a
valid pointer and strchr() can deal with an empty (NULL-terminated)
string perfectly fine, bit it makes the code a bit more obvious and
silences the following warning:
In function ‘Channel_UserHasMode’,
inlined from ‘Channel_Kick’ at channel.c:384:7:
channel.c:784:16: warning: ‘strchr’ reading 1 or more bytes from a region
of size 0 [-Wstringop-overread]
784 | return strchr(Channel_UserModes(Chan, Client), Mode) != NULL;
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
This was seen with "gcc (Debian 12.2.0-14) 12.2.0" at least.
