Handle the account-registration relay from an ircd

As the registration authority, fedserv accepts an account-registration request
relayed over the server link (ACCTREGISTER), creates the account through the
same store as classic NickServ REGISTER, and replies (ACCTREGRESULT) with
success or an error carrying the IRCv3 FAIL code — one account-creation path for
both the classic command and the draft/account-registration capability.

src/engine/mod.rs

@@ -3,7 +3,7 @@ pub mod service;
 pub mod state;
 
 use crate::proto::{NetAction, NetEvent};
-use db::Db;
+use db::{Db, RegError};
 use service::{Sender, Service, ServiceCtx};
 use state::Network;
 
@@ -46,10 +46,35 @@ impl Engine {
                 Vec::new()
             }
             NetEvent::Privmsg { from, to, text } => self.dispatch(&from, &to, &text),
+            NetEvent::AccountRequest { reqid, kind, account, p2, p3, .. } => {
+                self.account_request(reqid, kind, account, p2, p3)
+            }
             _ => Vec::new(),
         }
     }
 
+    // Authority side of the IRCv3 account-registration relay: create the account
+    // (same store as classic NickServ REGISTER) and answer the requesting ircd.
+    fn account_request(&mut self, reqid: String, kind: String, account: String, p2: String, p3: String) -> Vec<NetAction> {
+        if !kind.eq_ignore_ascii_case("REGISTER") {
+            return Vec::new(); // VERIFY / RESEND / STATUS: later
+        }
+        let email = if p2.is_empty() || p2 == "*" { None } else { Some(p2) };
+        let (status, code, message) = match self.db.register(&account, &p3, email) {
+            Ok(()) => ("success", "*", "Account registered."),
+            Err(RegError::Exists) => ("error", "ACCOUNT_EXISTS", "That account name is already registered."),
+            Err(RegError::Internal) => ("error", "TEMPORARILY_UNAVAILABLE", "Registration is unavailable, try again later."),
+        };
+        vec![NetAction::AccountResponse {
+            reqid,
+            kind,
+            account,
+            status: status.to_string(),
+            code: code.to_string(),
+            message: message.to_string(),
+        }]
+    }
+
     // Route a PRIVMSG addressed to a service (by uid or nick) into that service,
     // handing it the sender's resolved nick and the account store.
     fn dispatch(&mut self, from: &str, to: &str, text: &str) -> Vec<NetAction> {

src/proto/inspircd.rs

@@ -81,6 +81,23 @@ impl Protocol for InspIrcd {
                 }
             }
             "QUIT" => vec![NetEvent::Quit { uid: source.unwrap_or_default() }],
+            // account-registration relay from an ircd:
+            // ACCTREGISTER <reqid> <origin> <kind> <account> <p2> :<p3>
+            "ACCTREGISTER" => {
+                let a: Vec<&str> = tokens.by_ref().take(5).collect();
+                if a.len() == 5 {
+                    vec![NetEvent::AccountRequest {
+                        reqid: a[0].to_string(),
+                        origin: a[1].to_string(),
+                        kind: a[2].to_string(),
+                        account: a[3].to_string(),
+                        p2: a[4].to_string(),
+                        p3: trailing(rest),
+                    }]
+                } else {
+                    vec![]
+                }
+            }
             _ => vec![NetEvent::Unknown { line: line.to_string() }],
         }
     }
@@ -105,6 +122,13 @@ impl Protocol for InspIrcd {
             NetAction::Notice { from, to, text } => {
                 vec![format!(":{} NOTICE {} :{}", from, to, text)]
             }
+            // ACCTREGRESULT <reqid> <kind> <account> <status> <code> :<message>
+            NetAction::AccountResponse { reqid, kind, account, status, code, message } => {
+                vec![self.from_us(format!(
+                    "ACCTREGRESULT {} {} {} {} {} :{}",
+                    reqid, kind, account, status, code, message
+                ))]
+            }
             NetAction::Raw(s) => vec![s.clone()],
         }
     }

src/proto/mod.rs

@@ -12,6 +12,8 @@ pub enum NetEvent {
     Privmsg { from: String, to: String, text: String },
     UserConnect { uid: String, nick: String },
     Quit { uid: String },
+    // An ircd relaying an IRCv3 account-registration request to us as the authority.
+    AccountRequest { reqid: String, origin: String, kind: String, account: String, p2: String, p3: String },
     Unknown { line: String },
 }
 
@@ -24,6 +26,7 @@ pub enum NetAction {
     IntroduceUser { uid: String, nick: String, ident: String, host: String, gecos: String },
     Privmsg { from: String, to: String, text: String },
     Notice { from: String, to: String, text: String },
+    AccountResponse { reqid: String, kind: String, account: String, status: String, code: String, message: String },
     Raw(String),
 }