Quotas: reset one address, or give some back

POST /rules/{ref}/reset-quota takes an optional address (one entry of a
per-address quota starts again) and give (bytes taken off what was used,
one address's or everyone's, until the next reset). The firewall keeps
the adjustment for its next apply, which writes the new usage into the
ruleset; housecarld applies at once and saves the usage. hc rule
reset-quota --address/--give; Reset and Give back in the web UI, per
address in the usage dialog.

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

internal/server/server_test.go

@@ -7,6 +7,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"math"
 	"net/http"
 	"net/http/cookiejar"
 	"net/http/httptest"
@@ -45,6 +46,8 @@ type fakeFW struct {
 	fallback   bool // the boot fallback is in force
 	shadow     bool
 	ruleset    string // nft -j list ruleset ("": a default)
+	quotas     nft.QuotaUsage
+	adjusted   []nft.QuotaAdjust
 }
 
 func (f *fakeFW) Check(_ context.Context, st *model.State) error { return nil }
@@ -74,7 +77,12 @@ func (f *fakeFW) Table(context.Context) (*nft.Table, error) {
 	if len(f.applied) == 0 {
 		return nil, errors.New("No such file or directory: list table inet housecarl")
 	}
-	return &nft.Table{Counters: map[string]nft.Counter{"r1": {Packets: 3, Bytes: 180}}, Elements: f.elements, Fallback: f.fallback}, nil
+	return &nft.Table{Counters: map[string]nft.Counter{"r1": {Packets: 3, Bytes: 180}}, Elements: f.elements, Fallback: f.fallback, QuotaUsage: f.quotas}, nil
+}
+func (f *fakeFW) AdjustQuota(a nft.QuotaAdjust) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.adjusted = append(f.adjusted, a)
 }
 func (f *fakeFW) AddElement(_ context.Context, set, addr string, timeout int) error {
 	f.mu.Lock()
@@ -750,9 +758,38 @@ func TestQuotaResets(t *testing.T) {
 	if len(qs) != 1 || qs[0].NextReset == nil || qs[0].NextReset.Day() != 21 {
 		t.Errorf("quotas %+v", qs)
 	}
-	if code := e.call(e.token, "POST", "/rules/"+itoa(created.ID)+"/reset-quota", nil, nil); code != 200 || len(e.fw.resets) != 2 {
+	reset := "/rules/" + itoa(created.ID) + "/reset-quota"
+	if code := e.call(e.token, "POST", reset, nil, nil); code != 200 || len(e.fw.resets) != 2 {
 		t.Errorf("reset by hand: %d %v", code, e.fw.resets)
 	}
+
+	// One address started again, or some given back: the next apply
+	// (made at once) writes the new usage.
+	name := render.QuotaName(created.ID)
+	e.fw.quotas = nft.QuotaUsage{QuotaSets: map[string][]render.Element{name + "_v4": {{Addr: "10.0.10.23", Used: 6 << 30}},
+		name + "_v6": {{Addr: "2001:db8:1:2::", Used: 1 << 30}}}}
+	applies := len(e.fw.applied)
+	if code := e.call(e.token, "POST", reset, api.QuotaReset{Address: "10.0.10.23"}, nil); code != 200 {
+		t.Errorf("reset one address: %d", code)
+	}
+	if code := e.call(e.token, "POST", reset, api.QuotaReset{Address: "2001:db8:1:2:aaaa::7", Give: 2 << 30}, nil); code != 200 {
+		t.Errorf("give back to an IPv6 address (its /64): %d", code)
+	}
+	if code := e.call(e.token, "POST", reset, api.QuotaReset{Give: 1 << 30}, nil); code != 200 {
+		t.Errorf("give back to everyone: %d", code)
+	}
+	want3 := []nft.QuotaAdjust{{Name: name, Addr: "10.0.10.23", Give: math.MaxInt64}, {Name: name, Addr: "2001:db8:1:2::", Give: 2 << 30}, {Name: name, Give: 1 << 30}}
+	if !reflect.DeepEqual(e.fw.adjusted, want3) || len(e.fw.applied) != applies+3 || len(e.fw.resets) != 2 {
+		t.Errorf("adjusted %+v, applied %d more, resets %v", e.fw.adjusted, len(e.fw.applied)-applies, e.fw.resets)
+	}
+	for _, c := range []struct {
+		in   api.QuotaReset
+		code int
+	}{{api.QuotaReset{Address: "10.0.10.99"}, 404}, {api.QuotaReset{Address: "nonsense"}, 400}, {api.QuotaReset{Give: -5}, 400}} {
+		if code := e.call(e.token, "POST", reset, c.in, nil); code != c.code {
+			t.Errorf("%+v: %d, want %d", c.in, code, c.code)
+		}
+	}
 }
 
 // TestAutoConfirm: the client that made a change confirms it by itself: