readme: cover the full feature set (modes, ircv3, services, s2s, geoip, rpc, transports)

README.md

@@ -6,9 +6,11 @@ handler objects, and modules hook lifecycle events. Design goals:
 for TLS and `mio` for the epoll socket engine), and lock-free (a single core
 thread owns all state).
 
-> Status: early but capable. It boots, registers clients, speaks a large chunk of
-> the IRC + IRCv3 protocol (see **What works**), and one reactor thread has served
-> 5,000 concurrent connections in testing. Not battle-tested yet.
+> Status: capable and broad. It speaks a large slice of the IRC + IRCv3 protocol
+> — **100+ commands**, the full channel/user mode set, **28 IRCv3 capabilities**,
+> and **~55 pluggable modules** — with server-to-server linking, a services
+> interface, TLS, WebSocket, GeoIP and a JSON-RPC control plane. One reactor thread
+> has served 5,000 concurrent connections in testing. Not battle-tested yet.
 
 ## Run it
 
@@ -46,6 +48,19 @@ no cull list), an `Extensible` typemap instead of `void*` module data (freed
 automatically on drop), `&str` slices, and compiled-in trait objects instead of a
 fragile `.so` ABI.
 
+### Why a raw reactor, not async?
+
+IRC is one big shared mutable graph (users, channels, the nick index), and almost
+every command mutates it and then broadcasts. With one thread owning all of it,
+handlers are plain `&mut Server` code — no locks, no `.await`, no `Send + 'static`
+bounds. A multi-threaded async runtime would force that shared state behind
+mutexes or an actor mailbox, and a channel broadcast is serialized anyway, so
+you'd pay locking cost for parallelism the workload can't use. `mio` is the same
+readiness layer async runtimes are built on, so you keep the C50k scaling without
+the runtime. CPU-heavy or blocking work (DNS, TLS, outbound HTTP) is pushed to its
+own threads; the network scales out by **linking servers**, not by adding cores to
+one process.
+
 ### The two extension points
 
 - **Commands** (`src/command.rs`, `src/coremods/`) — a handler declares `name`,
@@ -59,34 +74,109 @@ fragile `.so` ABI.
 
 ## What works
 
-- Registration (`CAP`/`NICK`/`USER`), `PING`/`PONG` with idle + registration
-  timeouts, welcome burst (001–005) + ISUPPORT.
-- `JOIN`/`PART`/`NAMES`/`TOPIC`/`KICK`/`INVITE`, `PRIVMSG`/`NOTICE`/`TAGMSG`,
-  `NICK`, `WHO`/`WHOIS`/`WHOWAS`, `LIST`, `AWAY`, `QUIT`, `MOTD`/`LUSERS`.
-- **Full mode set** as handler objects: prefixes `+qaohv`, lists `+beI`, and
-  `+klmntispzONCTcSRMGu` plus flood/rate modes `+f/+j/+F`, redirect `+L`, word
-  filter `+g`, and acting **extbans** `m:`/`c:`/`n:`.
-- **IRC operators**: `OPER`/`KILL`/`WALLOPS`/`GLOBOPS`, `SAJOIN`/`SAPART`/`SANICK`/
-  `SAMODE`/`SATOPIC`/`SAKICK`, `CHGHOST`/`CHGIDENT`/`SETHOST`/`SETIDENT`,
-  `KLINE`/`GLINE`/`ZLINE` + `STATS`, snomasks (`+s`), `DIE`/`RESTART`, and a
-  reload-safe **`REHASH`** (keeps the running config if the file can't be read,
-  and announces the reload to every connected user).
-- **IRCv3**: `CAP` negotiation, `server-time`, `message-tags` + **`msgid`**,
-  `multi-prefix`, `away-notify`, `account-notify`, `extended-join`, `chghost`,
-  `userhost-in-names`, `echo-message`, `invite-notify`, `setname`,
-  `extended-monitor`, `SASL` (PLAIN, relayed to services), `WATCH`/`MONITOR`,
-  `SILENCE`, and `ACCEPT` + user `+g` **callerid** (only accepted users may PM you).
-- **Reverse-DNS on connect**: the classic `*** Looking up your hostname...`
-  connection notices, backed by a *real* forward-confirmed PTR resolver written
-  from scratch over UDP (no DNS crate) — resolves clients to hostnames, off the
-  core thread, fail-safe to the IP. Configurable (`resolve_hosts`,
-  `use_resolved_host`).
-- **TLS** (openssl) with `sslinfo`; keyed-SHA-256 host **cloaking** (`+x`);
-  **services-ready accounts** (`SVSLOGIN`/`SVSLOGOUT`, account-gated `+r/+R/+M`)
-  — the ircd is *ready* for an external services package, it is not one itself.
-- **Server-to-server linking**: handshake, UID/FJOIN netburst, cross-server
-  users and channels, nick-collision handling, netsplit.
-- An **antimixedutf8** anti-spam module (blocks mixed-script look-alike spam).
+### Registration & session
+- `CAP` negotiation, `NICK`/`USER`, `PING`/`PONG` with configurable idle +
+  registration timeouts, welcome burst (001–005) + ISUPPORT (optionally batched).
+- `WEBIRC` (real client IP from a trusted web gateway), `conn_waitpong` (require a
+  PONG cookie before registering — filters bots), `autodrop` (silently drop
+  pre-registration HTTP scanners), configurable nick/channel length limits.
+
+### Channels
+- `JOIN`/`PART`/`NAMES`/`TOPIC`/`KICK`/`INVITE`, plus `KNOCK`, `CYCLE`, `REMOVE`,
+  `UNINVITE`.
+- Bans / excepts / invex, ban **redirect** (`+b mask$#chan`), and matching +
+  acting **extbans** (below).
+
+### Messaging
+- `PRIVMSG`/`NOTICE`/`TAGMSG`, CTCP handling, `echo-message`, per-message `msgid`,
+  `server-time`, `account-tag`.
+- **CHATHISTORY** (`draft/chathistory`: `LATEST`/`BEFORE`/`AFTER`/`AROUND`/`BETWEEN`
+  /`TARGETS`) with the `+H` join backlog, **REDACT** (`draft/message-redaction`),
+  **MARKREAD** (`draft/read-marker`), and **multiline** (`draft/multiline`).
+- **RELAYMSG** (`draft/relaymsg`) — bridge messages under a spoofed relay nick.
+
+### The full mode set
+- **Prefixes** `+qaohv` (`~&@%+`), plus an optional network-staff prefix `+y` (`!`)
+  above owner (`operprefix` / `OJOIN`).
+- **List modes** `+b` ban, `+e` except, `+I` invex, `+g` word filter, `+X`
+  exemptchanops, `+w` auto-status.
+- **Parametered** `+k` key, `+l` limit, `+f` message-flood, `+j` join-flood, `+F`
+  nick-flood, `+L` redirect-when-full, `+H` history, `+B` anticaps, `+J`
+  kick-no-rejoin, `+d` delay-msg, `+K` no-repeat.
+- **Flags** `+imnpstz`, `+O` oper-only, `+N` no-nick, `+C` no-CTCP, `+T` no-notice,
+  `+c` no-colour, `+S` strip-colour, `+R` reg-only, `+M` reg-moderated, `+G` censor,
+  `+u` auditorium, `+Q` no-kicks, `+A` allow-invite, `+P` permanent, `+U`
+  op-moderated, `+D` delay-join.
+- **User modes** `+i w o x s g` plus `+B` bot, `+D` deaf, `+I` hide-chans, `+H`
+  hide-oper, `+r` logged-in, `+R` reg-only-PM, `+z` TLS-only-PM, `+W` show-whois,
+  `+h` helpop, `+c` common-chans-only.
+- **Extbans** — matching `g:` security-group, `y:` reputation, `r:` realname,
+  `j:` in-channel, `s:` server, `G:` country, `b:` other-channel's ban list; acting
+  `m:` mute, `c:` no-colour, `n:` no-nick.
+
+### Operators
+- `OPER`/`KILL`/`WALLOPS`/`GLOBOPS`, snomasks (`+s`) with an optional `chanlog`.
+- Overrides: `SAJOIN`/`SAPART`/`SANICK`/`SAMODE`/`SATOPIC`/`SAKICK`/`SAQUIT`,
+  `CHGHOST`/`CHGIDENT`/`CHGNAME`/`SETHOST`/`SETIDENT`/`SETIDLE`, `NICKLOCK`/
+  `NICKUNLOCK`, `SWHOIS`, `CHECK`, `CLEARCHAN`, `ALLTIME`, `OPERMOTD`, `VHOST`,
+  `TITLE`, oper-override-with-accountability, `operprefix`/`OJOIN`, `hidelist`/
+  `hidemode`.
+- **X-lines** `KLINE`/`GLINE`/`ZLINE`/`ELINE`/`SHUN`/`QLINE`/`CBAN`, persisted to
+  disk and restored on boot; `STATS`; on-demand `CONNECT`; `DIE`/`RESTART`; and a
+  reload-safe **`REHASH`** (keeps the running config if the file can't be read).
+
+### IRCv3 capabilities
+`sasl`, `server-time`, `message-tags` (+ `msgid`), `multi-prefix`, `away-notify`,
+`account-notify`, `extended-join`, `chghost`, `userhost-in-names`, `echo-message`,
+`invite-notify`, `setname`, `extended-monitor`, `account-tag`, `standard-replies`,
+`labeled-response`, `batch`, `cap-notify`, and drafts `chathistory`,
+`message-redaction`, `pre-away`, `metadata-2`, `multiline`, `account-registration`,
+`json-log`, `extended-isupport`, `relaymsg` — plus `WATCH`/`MONITOR`/`SILENCE` and
+`ACCEPT` (+ `+g` callerid).
+
+### Services interface & accounts
+- **SASL** PLAIN + EXTERNAL (TLS client-cert), relayed to an external services
+  server over S2S.
+- `SVSNICK`/`SVSJOIN`/`SVSPART`/`SVSMODE`/`SVSLOGIN`/`SVSLOGOUT`, `ENCAP`,
+  `METADATA`; account-gated modes (`+r`/`+R`/`+M`). The ircd is *ready* for an
+  external services package — it is not one itself.
+- Optional ircd-side account **registration** (`REGISTER`/`VERIFY` over an HTTP
+  API), CAPTCHA gating, and `EXTJWT` / file-host tokens.
+
+### Server-to-server linking
+Handshake, `UID`/`FJOIN` netburst, cross-server users and channels, multi-hop
+routing, nick-collision handling, and clean netsplit.
+
+### Anti-abuse
+`antimixedutf8` (look-alike script spam), `antirandom` (gibberish nicks), message
+flood (`+f`) + global rate limits, `connflood`/`connectban` (connection floods),
+`blockamsg`, `securelist`, `dnsbl`, CAPTCHA / challenge gating, `solvemsg`
+(arithmetic gate), `dccallow` (DCC filtering), `conn_waitpong`, `autodrop`.
+
+### GeoIP
+A **native MaxMind `.mmdb` reader** (no crate): the `G:<cc>` geoban extban, a
+`GEOIP` oper command, and a country line in WHOIS.
+
+### TLS, cloaking, transports
+- **TLS** (openssl) with `SSLINFO`, cert fingerprints, and `+z` secure-only.
+- Keyed-SHA-256 host **cloaking** (`+x`).
+- A **native WebSocket transport** (`ws://` and `wss://`) with real-IP / scheme
+  behind a trusted proxy.
+- Reverse-DNS on connect via a from-scratch forward-confirmed PTR resolver over
+  UDP (no DNS crate), off the core thread, fail-safe to the IP.
+
+### JSON-RPC control plane
+A native inbound HTTP server + JSON-RPC interface (no `serde`, no `hyper`) with
+token auth and ~30 methods across core/user/channel/server/stats/ban/message.
+
+### Native building blocks
+Everything is hand-rolled to stay dependency-light and `unsafe`-free: the DNS
+resolver, JWT (HS256), JSON scan/build, the mmdb reader, an HTTP client, and
+password hashing (`md5`/`sha1`/`sha256`/`sha512`/`pbkdf2`).
+
+### Everything is configurable
+Limits, thresholds, durations, timeouts and list sizes are all config keys — the
+literal in code is only the default; nothing operational is hardcoded.
 
 ## Originality