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>

internal/store/schema_test.go

@@ -42,7 +42,7 @@ func TestBaselineSchema(t *testing.T) {
 	st := openTestStore(t)
 	want := map[string]string{
 		"settings":              "key value",
-		"users":                 "id username password_hash role email all_domains all_inbound_domains created_at notify",
+		"users":                 "id username password_hash role email all_domains all_inbound_domains created_at notify email_confirmed_at",
 		"sessions":              "token_hash user_id created_at expires_at",
 		"domains":               "id name dkim_selector dmarc_rua created_at",
 		"user_domains":          "user_id domain_id",
@@ -64,6 +64,7 @@ func TestBaselineSchema(t *testing.T) {
 		"notify_addressees":     "key address told_at",
 		"sender_check_days":     "day down_seconds deferred messages estimated",
 		"delivery_log_days":     "day reconcile_closed reconcile_missed reconcile_contradicted tailer_blind_seconds queued_over_lifetime",
+		"user_links":            "token_hash user_id purpose email created_at expires_at",
 	}
 	rows, err := st.db.Query("SELECT name FROM sqlite_master WHERE type = 'table' AND name NOT LIKE 'sqlite_%' ORDER BY name")
 	if err != nil {
@@ -111,7 +112,7 @@ func TestBaselineSchema(t *testing.T) {
 		"idx_inbound_spam_log_created_at", "idx_inbound_spam_log_domain_created_at", "idx_inbound_spam_log_domain_id_created_at", "idx_inbound_spam_log_queue_id",
 		"idx_send_log_app_login", "idx_send_log_app_login_created_at", "idx_send_log_created_at", "idx_send_log_domain", "idx_send_log_domain_id", "idx_send_log_domain_id_created_at",
 		"idx_send_log_lines_queue_id", "idx_send_log_open", "idx_send_log_queue_id", "idx_send_log_refusal_line", "idx_send_log_rejected",
-		"idx_sessions_expires_at",
+		"idx_sessions_expires_at", "idx_user_links_user",
 	}
 	sort.Strings(wantIdx)
 	if strings.Join(indexes, " ") != strings.Join(wantIdx, " ") {
@@ -119,8 +120,8 @@ func TestBaselineSchema(t *testing.T) {
 	}
 
 	var version, appID int64
-	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 12 {
-		t.Errorf("user_version = %d, %v; want 12", version, err)
+	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 13 {
+		t.Errorf("user_version = %d, %v; want 13", version, err)
 	}
 	if err := st.db.QueryRow("PRAGMA application_id").Scan(&appID); err != nil || appID != applicationID {
 		t.Errorf("application_id = %#x, %v; want %#x", appID, err, applicationID)
@@ -196,8 +197,8 @@ func TestOpenMigratesA20Database(t *testing.T) {
 	}
 	defer st.Close()
 	var version int
-	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 12 {
-		t.Errorf("user_version = %d, %v; want 12", version, err)
+	if err := st.db.QueryRow("PRAGMA user_version").Scan(&version); err != nil || version != 13 {
+		t.Errorf("user_version = %d, %v; want 13", version, err)
 	}
 	if ok, err := st.UserExists(); err != nil || !ok {
 		t.Errorf("the user of the 2.0 database: exists = %v, %v", ok, err)