unrealircd/doc/RELEASE-NOTES.md

UnrealIRCd 6.0.3

A number of serious issues were discovered in UnrealIRCd 6. Among these is an issue which will likely crash the IRCd sooner or later if you /REHASH with any active clients connected. We suggest everyone who is running UnrealIRCd 6 to upgrade to 6.0.3.

If you are already running UnrealIRCd 6 then read below. Otherwise, jump straight to the summary about UnrealIRCd 6 to learn more about UnrealIRCd 6.

Fixes:

• Crash in WATCH if the IRCd has been rehashed at least once. After doing a REHASH with active clients it will likely corrupt memory. It may take several days until after the rehash for the crash to occur, or even weeks/months on smaller networks (accidental triggering, that is).
• A REHASH with certain remote includes setups could cause a crash or other weird and confusing problems such as complaining about unable to open an ipv6-database or missing snomask configuration. This only affected some people with remote includes, not all.
• Potential out-of-bounds write in sending code. In practice it seems harmless on most servers but this cannot be 100% guaranteed.
• Unlikely triggered log message would log uninitialized stack data to the log file or send it to ircops.
• Channel ops could not remove halfops from a user (-h).
• After using the RESTART command (not recommended) the new IRCd was often no longer writing to log files.
• Fix compile problem if you choose to use cURL remote includes but don't have cURL on the system and ask UnrealIRCd to compile cURL.

Enhancements:

• The default text log format on disk changed. It now includes the server name where the event was generated. Without this, it was sometimes difficult to trace problems, since previously it sometimes looked like there was a problem on your server when it was actually another server on the network.
  • Old log format: [DATE TIME] subsystem.EVENT_ID loglevel: ........
  • New log format: [DATE TIME] servername subsystem.EVENT_ID loglevel: ........

Changes:

• Any MOTD lines added by services via SVSMOTD are now shown at the end of the MOTD-on-connect (unless using a shortmotd). Previously the lines were only shown if you manually ran the MOTD command.

Developers and protocol:

• LIST C<xx now means: filter on channels that are created less than xx minutes ago. This is the opposite of what we had earlier. LIST T<xx is now supported as well (topic changed in last xx minutes), it was already advertised in ELIST but support was not enabled previously.

UnrealIRCd 6.0.2

UnrealIRCd 6.0.2 comes with several nice feature enhancements along with some fixes. It also includes a fix for a crash bug that can be triggered by ordinary users.

Fixes:

• Fix crash that can be triggered by regular users if you have any deny dcc blocks in the config or any spamfilters with the d (DCC) target. NOTE: You don't have to upgrade to 6.0.2 to fix this, you can also hot-patch this issue without restart, see the news announcement.
• Windows: fix crash with IPv6 clients (local or remote) due to GeoIP lookup
• Fix infinite hang on "Loading IRCd configuration" if DNS is not working. For example if the 1st DNS server in /etc/resolv.conf is down or refusing requests.
• Some MODE server-to-server commands were missing a timestamp at the end, even though this is mandatory for modes coming from a server.
• The channeldb module now converts letter extbans to named extbans (eg ~a to ~account). Previously it did not, which caused letter extbans to appear in the banlist. Later on, when linking servers, this would cause duplicate entries to appear as well, with both the old and new format. The extbans were still effective though, so this is mostly a visual +b/+e/+I list issue.
• Some Extended Server Bans were not working correctly for WEBIRC proxies. In particular, a server ban or exempt (ELINE) on ~country:XX was only checked against the WEBIRC proxy.

Enhancements:

• Support for logging to a channel. Similar to snomasks but then for channels.
• Command line interface changes:
  • The CLI tool now communicates to the running UnrealIRCd process via a UNIX socket to send commands and retrieve output.
  • The command ./unrealircd rehash will now show the rehash output, including warnings and errors, and return a proper exit code.
  • The same for ./unrealircd reloadtls
  • New command ./unrealircd status to show if UnrealIRCd is running, the version, channel and user count, ..
  • The command ./unrealircd genlinkblock is now documented and is referred to from the Linking servers tutorial.
  • On Windows in the C:\Program Files\UnrealIRCd 6\bin directory there is now an unrealircdctl.exe that can be used to do similar things to what you can do on *NIX. Supported operations are: rehash, reloadtls, mkpasswd, gencloak and spkifp.
• New option set::server-notice-show-event which can be set to no to hide the event information (eg connect.LOCAL_CLIENT_CONNECT) in server notices. This can be overridden per-oper in the Oper block via oper::server-notice-show-event.
• Support for IRC over UNIX sockets (on the same machine), if you specify a file in the listen block instead of an ip/port. This probably won't be used much, but the option is there. Users will show up with a host of localhost and IP 127.0.0.1 to keep things simple.
• The MAP command now shows percentages of users
• Add WHO option to search clients by time connected (eg. WHO <300 t to search for less than 300 seconds)
• Rate limiting of MODE nick -x and -t via new vhost-flood option in set::anti-flood block.

Changes:

• Update Russian help.ru.conf.

Developers and protocol:

• People packaging UnrealIRCd (eg. to an .rpm/.deb):
  • Be sure to pass the new --with-controlfile configure option
  • There is now an unrealircdctl tool that the unrealircd shell script uses, it is expected to be in bindir.
• SVSMODE #chan -b nick will now correctly remove extbans that prevent nick from joining. This fixes a bug where it would remove too much (for ~time) or not remove extbans (most other extbans, eg ~account). SVSMODE #chan -b has also been fixed accordingly (remove all bans preventing joins). Note that all these commands do not remove bans that do not affect joins, such as ~quiet or ~text.
• For module coders: setting the EXTBOPT_CHSVSMODE flag in extban.options is no longer useful, the flag is ignored. We now decide based on BANCHK_JOIN being in extban.is_banned_events if the ban should be removed or not upon SVS(2)MODE -b.

UnrealIRCd 6.0.1.1

Fixes:

• In 6.0.1.1: extended bans were not properly synced between U5 and U6. This caused missing extended bans on the U5 side (MODE was working OK, this only happened when linking servers)
• Text extbans did not have any effect (+b ~text:censor:*badword*)
• Timed bans were not expiring if all servers on the network were on U6
• Channel mode +f could place a timed extban with ~t instead of ~time
• Crash when unloading any of the vhoaq modules at runtime
• ./unrealircd upgrade not working on FreeBSD and not with self-compiled cURL
• Some log messages being wrong (CHGIDENT, CHGNAME)
• Remove confusing high cpu load warning

Enhancements:

• Error on unknown snomask in set::snomask-on-oper and oper::snomask.
• TKL add/remove/expire messages now show [duration: 60m] instead of the [expires: ZZZ GMT] string since that is what people are more interested in and is not affected by time zones. The format in all the 3 notices is also consistent now.

UnrealIRCd 6.0.0

Many thanks to k4be for his help during development, other contributors for their feedback and patches, the people who tested the beta's and release candidates, translators and everyone else who made this release happen!

Summary

UnrealIRCd 6 comes with a completely redone logging system (with optional JSON support), named extended bans, four new IRCv3 features, geoip support and remote includes support built-in.

Additionally, things are more customizable such as what gets sent to which snomask. All the +vhoaq channel modes are now modular as well, handy for admins who don't want or need halfops or +q/+a. For WHOIS it is now customizable in detail who gets to see what.

A summary of the features is available at What's new in UnrealIRCd 6. For complete information, continue reading the release notes below. The sections below contain all the details.

Upgrading from UnrealIRCd 5

The previous stable series, UnrealIRCd 5, will no longer get any new features. We still do bug fixes until July 1, 2022. In the 12 months after that, only security issues will be fixed. Finally, after July 1, 2023, all support will stop.

If you want to hold off for a while because you are cautious or if you depend on 3rd party modules (which may not have been upgraded yet by their authors) then feel free to wait a while.

If you are upgrading from UnrealIRCd 5 to 6 then you can use your existing configuration and files. There's no need to start from scratch. However, you will need to make a few updates, see Upgrading from 5.x to 6.x.

Enhancements

• Completely new log system and snomasks overhaul
  • Both logging and snomask sending is done by a single logging function
  • Support for JSON logging to disk, instead of the default text format. JSON logging adds lot of detail to log messages and consistently expands things like client with properties like hostname, connected_since, reputation, modes, etc.
  • The JSON data is also sent to all IRCOps who request the unrealircd.org/json-log capability. The data is then sent in a message-tag called unrealircd.org/json-log. This makes it ideal for client scripts and bots to do automated things.
  • A new style log { } block is used to map what log messages should be logged to disk, and which ones should be sent to snomasks.
  • The default logging to snomask configuration is in snomasks.default.conf which everyone should include from unrealircd.conf. That is, unless you wish to completely reconfigure which logging goes to which snomasks yourself, which is also an option now.
  • See Snomasks on the new snomasks - lots of letters changed!
  • See FAQ: Converting log { } block on how to change your existing log { } blocks for disk logging.
  • We now have a consistent log format and log messages can be multiline.
  • Colors are enabled by default in snomask server notices, these can be disabled via set::server-notice-colors and also in oper::server-notice-colors
  • Support for logging to a channel. Similar to snomasks but then for channels. Requires UnrealIRCd 6.0.2 or later
• Almost all channel modes are modularized
  • Only the three list modes (+b/+e/+I) are still in the core
  • The five level modes (+vhoaq) are now also modular. They are all loaded by default but you can blacklist one or more if you don't want them. For example to disable halfop: blacklist-module chanmodes/halfop;
  • Support for compiling without PREFIX_AQ has been removed because people often confused it with disabling +a/+q which is something different.
• Named extended bans
  • Extbans now no longer show up with single letters but with names. For example +b ~c:#channel is now +b ~channel:#channel.
  • Extbans are automatically converted from the old to the new style, both from clients and from/to older UnrealIRCd 5 servers. The auto-conversion also works fine with complex extbans such as +b ~t:5:~q:nick!user@host to +b ~time:5:~quiet:nick!user@host.
• New IRCv3 features:
  • MONITOR: an alternative for WATCH to monitor other users ("notify list").
  • draft/extended-monitor: extensions for MONITOR, still in draft.
  • invite-notify: report channel invites to other chanops (or users) in a machine readable way.
  • setname: notify clients about realname (gecos) changes.
• GeoIP lookups are now done by default
  • This shows the country of the user to IRCOps in WHOIS and in the "user connecting" line.
  • By default the geoip_classic module is loaded, for which we provide a mirror of database updates at unrealircd.org. This uses the classic geolite library that is now shipped with UnrealIRCd
  • Other options are the geoip_maxmind and geoip_csv modules.
• Configure WHOIS output in a very precise way
  • You can now decide which fields (eg modes, geo, certfp, etc) you want to expose to who (everyone, self, oper).
  • See set::whois-details for more details.
• We now ship with 3 cloaking modules and you need to load 1 explicitly via loadmodule:
  • cloak_sha256: the recommended module for anyone starting a new network. It uses the SHA256 algorithm under the hood.
  • cloak_md5: for anyone who is upgrading their network from older UnrealIRCd versions. Use this so your cloaked host bans remain the same.
  • cloak_none: if you don't want any cloaking, not even as an option to your users (rare)
• Remote includes are now supported everywhere in the config file.
  • Support for https:// fetching is now always available, even if you don't compile with libcurl support.
  • Anywhere an URL is encountered on its own, it will be fetched automatically. This makes it work not only for includes and motd (which was already supported) but also for any other file.
  • To prevent something from being interpreted as a remote include URL you can use 'value' instead of "value".
• Invite notification: set set::normal-user-invite-notification yes; to make chanops receive information about normal users inviting someone to their channel. The name of this setting may change in a later version.
• Websocket: you can add a listen::options::websocket::forward 1.2.3.4 option to make unrealircd accept a Forwarded (RFC 7239) header from a reverse proxy connecting from 1.2.3.4 (plans to accept legacy X-Forwarded-For and a proxy password too). This feature is currently experimental.

Changes

• TLS cipher and some other information is now visible for remote clients as well, also in [secure: xyz] connect line.
• Error messages in remote includes use the url instead of a temporary file
• Downgrading from UnrealIRCd 6 is only supported down to 5.2.0 (so not lower like 5.0.x). If this is a problem then make a copy of your db files (eg: reputation.db).

Removed

• /REHASH -motd and -opermotd are gone, just use /REHASH

Breaking changes

See https://www.unrealircd.org/docs/Upgrading_from_5.x, but in short:

You can use the unrealircd.conf from UnrealIRCd 5, but you need to make a few changes:

• You need to add include "snomasks.default.conf";
• You need to load a cloaking module explicitly. Assuming you already have a network then add: loadmodule "cloak_md5";
• The log block(s) need to be updated, use something like:

  log {
          source {
              !debug;
              all;
          }
          destination {
              file "ircd.log" { maxsize 100M; }
          }
  }
  

Module coders (API changes)

• Be sure to bump the version in the module header from unrealircd-5 to unrealircd-6
• We use a lot more const char * now (instead of char *). In particular parv is const now and so are a lot of arguments to hooks. This will mean that in your module you have to use more const too. The reason for this change is to indicate that certain strings should not be touched, as doing so is dangerous or could have had side-effects that were unpredictable.
• Logging has been completely redone. Don't use ircd_log(), sendto_snomask(), sendto_ops() and sendto_realops() anymore. Instead use unreal_log() which handles both logging to disk and notifying IRCOps.
• Various struct member names changed, in particular in ConfigEntry and ConfigFile, but also channel->chname is channel->name now.
• get_channel() is now make_channel() and creates if needed, otherwise use find_channel()
• The Extended Ban API has been changed a lot. We use a BanContext struct now that we pass around a lot. You also don't need to do +3 magic anymore on the string as it is handled in another layer. When registering the extended ban, .flag is now .letter, and you also need to set a .name to a string due to named extended bans. Have a look at the built-in extban modules to see how to handle the changes.
• ModData now has an option MODDATA_SYNC_EARLY. See under Server protocol.
• If you want to lag someone up, don't touch client->since, but instead use: add_fake_lag(client, msec)
• Some client/user struct changes, with client->user->account (instead of svid) and client->uplink->name being the most important ones.
• Possibly more, but above is like 90%+ of the changes that you will encounter.

Server protocol

• When multiple related SJOIN messages are generated for the same channel then we now only send the current channel modes (eg +sntk key) in the first SJOIN and not in the other ones as they are unneeded for the immediate followup SJOINs, they waste unnecessary bytes and CPU. Such messages may be generated when syncing a channel that has dozens of users and/or bans/exempts/invexes. Ideally this should not need any changes in other software, since we already supported such messages in the past and code for handling it exists way back to 3.2.x, but you better check to be sure!
• If you send PROTOCTL NEXTBANS then you will receive extended bans with Named EXTended BANs instead of letters (eg: +b ~account:xyz), otherwise you receive them with letters (eg: +b ~a:xyz).
• Some ModData of users is (also) communicated in the UID message while syncing using a message tag that only appears in server-to-server traffic, s2s-md/moddataname=value. Thus, data such as operinfo, tls cipher, geoip, certfp, sasl and webirc is communicated at the same time as when a remote connection is added. This makes it that a "connecting from" server notice can include all this information and also so code can make an immediate decission on what to do with the user in hooks. ModData modules need to set mreq.sync = MODDATA_SYNC_EARLY; if they want this. Servers of course need to enable MTAGS in PROTOCTL to see this.
• The SLOG command is used to broadcast logging messages. This is done for log::destination remote, as used in doc/conf/snomasks.default.conf, for example for link errors, oper ups, flood messages, etc. It also includes all JSON data in a message tag when PROTOCTL MTAGS is used.
• Bounced modes are gone: these were MODEs that started with a & which servers were to act on with reversed logic (add becoming remove and vice versa) and never to send something back to that server. In practice this was almost never used and complicated the code (way) too much.

Client protocol

• Extended bans now have names instead of letters. If a client sends the old format with letters (eg +b ~a:XYZ) then the server will convert it to the new format with names (eg: +b ~account:XYZ)
• Support for MONITOR and the other IRCv3 features (see Enhancements)