password-reset: a confirmed e-mail, then a link to reset the password

Agreed by the owner on 2026-10-13 ("the e-mail must be confirmed");
notifications to an unconfirmed address settled on 2026-10-17: "Без
подтверждения слать". Mockups 2f5f5b2, route guard b7bbb2c, panel guard
0774da2.

Migration 0013: users.email_confirmed_at ('' for every address saved
before it) and user_links - the SHA-256 of a link's token, its user,
purpose (confirm, reset), address, created and expiry. A changed address
loses its mark (keepConfirmed, in UpdateUser and SaveUser).

internal/web/auth/links.go. A link is 256 bits from crypto/rand, mailed as
https://SELFPOST_HOSTNAME/... - never the request's Host. Confirmation:
24 h, sent when an address is saved (Account, or the global role's user
form) and by Account's Send the link again; its page /confirm/<token> has
a button (a GET changes nothing) and confirms only for a session of its
own account. Reset: /login/reset asks for a username and answers the same
for every name (the sign-in page, "If that account has a confirmed e-mail,
the link is on its way"), mailing after the answer; only a confirmed
address gets one, none within ten minutes of the last, five links an hour
per account, five requests in 15 minutes per client address;
/login/reset/<token> (30 min) sets the password with the link taken in
the same transaction that checks the address again
(store.TakeResetLink), then ends every session. Changing the e-mail on
Account asks for the current password. A password set on Account or the
user form removes the reset links; a restore removes every link; the stop
waits for links being mailed (Server.Drain); a rejected request's log line
hides a link's token (loggedPath).

Reviewed for security before the commit (2026-10-17): no high; two
medium and five low, all fixed here - confirming needs the account's
session and the mail does not name the account (a mistyped address was a
takeover); a reset request neither replaces the links already sent nor
spends the account's quota inside ten minutes; take-and-set atomic; the
confirmation mail sent after the answer; the stop waits for mail; a
restore deletes the links; the token kept out of the log.

Tests: store TestUserLinks, TestUserLinkTakenOnce, TestEmailConfirmation,
TestTakeResetLink; auth TestResetSendsALinkOnlyToAConfirmedAddress,
TestResetLinkSetsThePasswordOnce, TestResetLinkDiesWithTheAddress,
TestResetRequestsAreLimited, TestResetRequestsAreSpaced, TestConfirmLink,
TestLinkPathsWithoutAToken; handlers TestAccountEmailIsConfirmedByItsLink,
TestUserFormSendsANewAddressItsLink; web TestLoggedPathHidesTokens; the
view's pages and fixtures; e2e password_reset_by_e_mail runs it through
the sink (and checks a link from before the restore is dead). go vet +
go test (26 packages) and make e2e on the test server for this tree.

Docs: guide § Account, security.md (the bullet and what ends sessions),
architecture (routes), schema-migrations (row 13, users, user_links),
help #account (word for word with the mockup), roadmap row done,
CHANGELOG [Unreleased].

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

cmd/panel/httpserver.go

@@ -169,7 +169,9 @@ func serveHTTP(ctx context.Context, cfg config, st *store.Store) error {
 	srv := newHTTPServer(cfg.httpAddr, srvApp.Handler())
 
 	// Shut the server down cleanly when the process is asked to stop.
+	shutDown := make(chan struct{})
 	go func() {
+		defer close(shutDown)
 		<-ctx.Done()
 		shutdownCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
 		defer cancel()
@@ -180,5 +182,13 @@ func serveHTTP(ctx context.Context, cfg config, st *store.Store) error {
 	if err := srv.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
 		return err
 	}
+	// ListenAndServe returns at the stop, before its requests have
+	// (net/http, Server.Shutdown); Shutdown returns once they have. The links
+	// they mail after their answers go on after that, and end before the
+	// database closes.
+	<-shutDown
+	drainCtx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+	srvApp.Drain(drainCtx)
 	return nil
 }