Merge pull request #185 from BaaRai/feat/target-gate-redirect-hops

feat(intercept): check every redirect hop against the target gate (S3b 1.9)

agent/chat.go

@@ -128,13 +128,10 @@ func (c *ChatAgent) Chat(ctx context.Context, agentKey, sessionID, message strin
 		Provider:        c.prov,
 		SystemPrompt:    system,
 		DynamicBoundary: boundary,
-		Tools:           tools,
+		Tools:           withWebFetch(tools, c.proxyAddr, c.proxyCACert), // WebFetch: routed through the recording proxy for tracing; loads the proxy CA to verify MITM-resigned HTTPS certificates; every redirect hop is gated
 		DeferredTools:   def.Deferred,
 		UnlockSet:       def.Unlock,
 		PermissionMode:  permission.ModeBypass,
-		EnableWebFetch:  true, // routed through the recording proxy for tracing; loads the proxy CA to verify MITM-resigned HTTPS certificates
-		WebFetchProxy:   c.proxyAddr,
-		WebFetchCACert:  c.proxyCACert,
 		// Web search (optional). ddgs needs no key; brave-free needs BraveKey; tavily needs TavilyKey.
 		// WebSearchProxy is a dedicated egress proxy (http/https/socks5), unrelated to the traffic-recording MITM proxy; empty = direct.
 		EnableWebSearch:       ws.Enabled,

agent/mainagent.go

@@ -144,13 +144,10 @@ func (m *MainAgent) Chat(ctx context.Context, taskID int64, mainSeg int, as *db.
 		Provider:        m.prov,
 		SystemPrompt:    system,
 		DynamicBoundary: boundary,
-		Tools:           tools,
+		Tools:           withWebFetch(tools, m.proxyAddr, m.proxyCACert), // WebFetch: routed through the recording proxy for tracing; loads the proxy CA to verify MITM-resigned HTTPS certificates; every redirect hop is gated
 		DeferredTools:   def.Deferred,
 		UnlockSet:       def.Unlock,
 		PermissionMode:  permission.ModeBypass,
-		EnableWebFetch:  true, // routed through the recording proxy for tracing; loads the proxy CA to verify MITM-resigned HTTPS certificates
-		WebFetchProxy:   m.proxyAddr,
-		WebFetchCACert:  m.proxyCACert,
 		// Web search (optional). ddgs needs no key; brave-free needs BraveKey; tavily needs TavilyKey.
 		// WebSearchProxy is a dedicated egress proxy (http/https/socks5), unrelated to the traffic-recording MITM proxy; empty = direct.
 		EnableWebSearch:       m.webSearch.Enabled,

agent/planner.go

@@ -426,13 +426,10 @@ func (p *Planner) Plan(ctx context.Context, taskID int64, as *db.AssetStore, ts
 		Provider:        p.prov,
 		SystemPrompt:    system,
 		DynamicBoundary: boundary,
-		Tools:           tools,
+		Tools:           withWebFetch(tools, p.proxyAddr, p.proxyCACert), // WebFetch: route through the recording proxy for traceability; load the proxy CA to verify MITM-re-signed HTTPS certs; every redirect hop is gated
 		DeferredTools:   def.Deferred,
 		UnlockSet:       def.Unlock,
 		PermissionMode:  permission.ModeBypass,
-		EnableWebFetch:  true, // route through the recording proxy for traceability; load the proxy CA to verify MITM-re-signed HTTPS certs
-		WebFetchProxy:   p.proxyAddr,
-		WebFetchCACert:  p.proxyCACert,
 		// Web search (optional). ddgs needs no key; brave-free needs BraveKey; tavily needs TavilyKey.
 		// WebSearchProxy is a dedicated egress proxy (http/https/socks5), unrelated to the traffic-recording MITM proxy; empty = direct.
 		EnableWebSearch:       p.webSearch.Enabled,

agent/webfetch.go

@@ -0,0 +1,19 @@
+package agent
+
+import (
+	"github.com/Autumn-27/artex/intercept"
+	actool "github.com/Autumn-27/norma/tool"
+)
+
+// withWebFetch returns tools plus the WebFetch tool of an agent session. Every
+// agent kind builds WebFetch here instead of through agentcore's EnableWebFetch,
+// which has no option for a redirect policy: every redirect hop goes through the
+// target gate (intercept.RedirectCheck), on the client that uses proxy and on
+// the direct retry client alike. The tool is added after the session's own
+// tools, where agentcore adds it, so the tool list keeps its order. caCert is the
+// recording proxy's CA, trusted to verify the HTTPS it re-signs. tools is not
+// modified.
+func withWebFetch(tools []actool.CoreTool, proxy, caCert string) []actool.CoreTool {
+	webFetch := actool.NewWebFetch(actool.WebFetchConfig{Proxy: proxy, CACert: caCert, CheckRedirect: intercept.RedirectCheck("WebFetch")})
+	return append(tools[:len(tools):len(tools)], webFetch)
+}

agent/webfetch_redirect_test.go

@@ -0,0 +1,228 @@
+package agent
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/Autumn-27/artex/db"
+	"github.com/Autumn-27/artex/guard"
+	"github.com/Autumn-27/artex/intercept"
+	"github.com/Autumn-27/norma/llm"
+	actool "github.com/Autumn-27/norma/tool"
+)
+
+// Step 1.9: the WebFetch tool of every agent kind checks each redirect hop
+// against the target gate, on the primary client and on the direct retry
+// client. With the gate off it follows redirects as before.
+
+// passHooks lets every tool call run.
+type passHooks struct{}
+
+func (passHooks) PreToolUse(context.Context, string, []byte) (bool, string, []byte) {
+	return false, "", nil
+}
+
+func (passHooks) PostToolUse(context.Context, string, []byte, []byte, bool) {}
+
+func (passHooks) Stop(context.Context, []llm.Message) (bool, []string, string) {
+	return false, nil, ""
+}
+
+// redirectPair is a server that redirects to a second one on another port of
+// 127.0.0.1, so the hop is another target (an IP literal: never resolved).
+type redirectPair struct {
+	start, final         string // URLs
+	startHits, finalHits *atomic.Int64
+	finalKey             string // host:port of the redirect target
+}
+
+func newRedirectPair(t *testing.T) redirectPair {
+	t.Helper()
+	p := redirectPair{startHits: &atomic.Int64{}, finalHits: &atomic.Int64{}}
+	final := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		p.finalHits.Add(1)
+		w.Header().Set("Content-Type", "text/plain")
+		_, _ = w.Write([]byte("redirect-target-reached"))
+	}))
+	t.Cleanup(final.Close)
+	start := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		p.startHits.Add(1)
+		http.Redirect(w, r, final.URL+"/final", http.StatusFound)
+	}))
+	t.Cleanup(start.Close)
+	u, _ := url.Parse(final.URL)
+	p.start, p.final, p.finalKey = start.URL+"/start", final.URL+"/final", u.Host
+	return p
+}
+
+// gatedScope is a gated target scope on task taskID, whose rows are removed
+// afterwards.
+func gatedScope(t *testing.T, d *db.DB, taskID string) intercept.TargetScope {
+	t.Helper()
+	t.Cleanup(func() { _, _ = d.Exec(`DELETE FROM intercept_pending WHERE task_id=$1`, taskID) })
+	return intercept.TargetScope{TaskID: taskID, Enabled: func() bool { return true },
+		WaitBound: intercept.DefaultTargetWaitBound, Interceptor: intercept.New(d)}
+}
+
+// openRedirectRequests returns the target keys of the open requests of task.
+func openRedirectRequests(t *testing.T, d *db.DB, taskID string) []string {
+	t.Helper()
+	rows, err := d.Query(`SELECT target_key FROM intercept_pending WHERE task_id=$1 AND status='pending' AND target_key IS NOT NULL ORDER BY id`, taskID)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer rows.Close()
+	var keys []string
+	for rows.Next() {
+		var k string
+		if err := rows.Scan(&k); err != nil {
+			t.Fatal(err)
+		}
+		keys = append(keys, k)
+	}
+	return keys
+}
+
+func fetchInputJSON(u string) string {
+	b, _ := json.Marshal(map[string]string{"url": u})
+	return string(b)
+}
+
+// Each agent kind runs a scripted WebFetch on a URL that redirects to a target
+// no pin covers. The hooks let the call run, so the hop is what the gate sees:
+// each kind must stop at the hop, leave the redirect target untouched and open
+// one request for it. A fifth agent kind added without the redirect policy
+// fails this table once it is added to it.
+func TestWebFetchRedirectCheckWiredOnEveryAgentKind(t *testing.T) {
+	for _, kind := range []string{"worker", "planner", "mainagent", "chat"} {
+		t.Run(kind, func(t *testing.T) {
+			f := newHookReachFixture(t)
+			d := testDB(t)
+			t.Cleanup(func() { _ = d.Close() })
+			pair := newRedirectPair(t)
+			scope := gatedScope(t, d, f.taskID)
+			ctx := intercept.WithTargetScope(t.Context(), scope)
+			prov := toolCallThenStop("WebFetch", fetchInputJSON(pair.start))
+
+			switch kind {
+			case "worker":
+				payload := map[string]any{"summary": "redirect probe"}
+				intentID, err := f.ts.AddNode("intent", payload, 0, "running", "planner", nil)
+				if err != nil {
+					t.Fatal(err)
+				}
+				raw, _ := json.Marshal(payload)
+				w := NewWorker(prov, "test-model", f.workDir, nil, 0, 3)
+				if _, _, err := w.Execute(ctx, "work#1", f.expID, nil, f.ts, &db.Node{ID: intentID, Payload: raw}, passHooks{}, nil, nil, nil); err != nil {
+					t.Fatal(err)
+				}
+			case "planner":
+				p := NewPlanner(prov, "test-model", f.workDir, nil, 0, 3)
+				if _, _, err := p.Plan(ctx, f.expID, nil, f.ts, "probe goal", nil, passHooks{}, nil); err != nil {
+					t.Fatal(err)
+				}
+			case "mainagent":
+				m := NewMainAgent(prov, "test-model", f.workDir, nil, 0, 3)
+				if _, err := m.Chat(ctx, f.expID, 0, nil, f.ts, "probe goal", "status?", passHooks{}, nil, nil, nil, nil, nil); err != nil {
+					t.Fatal(err)
+				}
+			case "chat":
+				c := NewChatAgent(prov, "test-model", t.TempDir(), nil, 0)
+				c.SetGuard(guard.New())
+				if _, err := c.Chat(ctx, "assistant", "conv-redirect-probe", "fetch it", 3, 0, false, nil); err != nil {
+					t.Fatal(err)
+				}
+			}
+
+			if pair.startHits.Load() != 1 {
+				t.Fatalf("the fetch did not run: %d hits on the origin", pair.startHits.Load())
+			}
+			if pair.finalHits.Load() != 0 {
+				t.Fatal("the redirect was followed to a target no pin covers")
+			}
+			if keys := openRedirectRequests(t, d, f.taskID); len(keys) != 1 || keys[0] != pair.finalKey {
+				t.Fatalf("open requests = %v, want one for %s", keys, pair.finalKey)
+			}
+		})
+	}
+}
+
+// The direct retry client carries the policy too: with a proxy that refuses
+// the connection, WebFetch retries without it, reaches the origin, and the
+// hop is still stopped.
+func TestWebFetchRedirectCheckOnDirectRetry(t *testing.T) {
+	d := testDB(t)
+	t.Cleanup(func() { _ = d.Close() })
+	expID, err := d.CreateExploration("redirect retry probe", "the direct retry client checks redirects")
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { _, _ = d.Exec(`DELETE FROM explorations WHERE id=$1`, expID) })
+	taskID := fmt.Sprint(expID)
+	pair := newRedirectPair(t)
+	ctx := intercept.WithTargetScope(t.Context(), gatedScope(t, d, taskID))
+
+	out, isErr := callWebFetch(t, ctx, "http://127.0.0.1:1", pair.start)
+	if !isErr || !strings.Contains(out, intercept.TargetApprovalPending) || !strings.Contains(out, "redirects to "+pair.finalKey) {
+		t.Fatalf("retried fetch: error=%v out=%q", isErr, out)
+	}
+	if pair.startHits.Load() != 1 || pair.finalHits.Load() != 0 {
+		t.Fatalf("hits origin=%d target=%d, want the origin reached by the retry and the target untouched", pair.startHits.Load(), pair.finalHits.Load())
+	}
+	if keys := openRedirectRequests(t, d, taskID); len(keys) != 1 || keys[0] != pair.finalKey {
+		t.Fatalf("open requests = %v, want one for %s", keys, pair.finalKey)
+	}
+}
+
+// With the gate off, or without a scope, WebFetch follows redirects as it did
+// with agentcore's own tool: to the end of the chain, and the same error after
+// 10 hops. No database.
+func TestWebFetchRedirectGateOffUnchanged(t *testing.T) {
+	loop := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Redirect(w, r, r.URL.Path+"x", http.StatusFound)
+	}))
+	t.Cleanup(loop.Close)
+	for name, ctx := range map[string]context.Context{
+		"no scope": t.Context(),
+		"flag off": intercept.WithTargetScope(t.Context(), intercept.TargetScope{TaskID: "7", Enabled: func() bool { return false },
+			WaitBound: time.Minute, Interceptor: intercept.New(nil)}),
+	} {
+		pair := newRedirectPair(t)
+		for _, proxy := range []string{"", "http://127.0.0.1:1"} {
+			if out, isErr := callWebFetch(t, ctx, proxy, pair.start); isErr || !strings.Contains(out, "redirect-target-reached") {
+				t.Fatalf("%s, proxy %q: error=%v out=%q", name, proxy, isErr, out)
+			}
+		}
+		if pair.finalHits.Load() != 2 {
+			t.Fatalf("%s: %d hits on the redirect target, want 2", name, pair.finalHits.Load())
+		}
+		got, _ := callWebFetch(t, ctx, "", loop.URL+"/l")
+		want := actool.NewWebFetch(actool.WebFetchConfig{}).Call
+		res, err := want(ctx, json.RawMessage(fetchInputJSON(loop.URL+"/l")), &actool.ToolContext{})
+		if err != nil || got != res.Flatten() || !strings.Contains(got, "stopped after 10 redirects") {
+			t.Fatalf("%s: redirect loop: %q, want agentcore's %q", name, got, res.Flatten())
+		}
+	}
+}
+
+// callWebFetch runs the WebFetch tool the agents build, with proxy.
+func callWebFetch(t *testing.T, ctx context.Context, proxy, u string) (string, bool) {
+	t.Helper()
+	tools := withWebFetch(nil, proxy, "")
+	if len(tools) != 1 || tools[0].Name() != "WebFetch" {
+		t.Fatalf("withWebFetch built %d tools", len(tools))
+	}
+	res, err := tools[0].Call(ctx, json.RawMessage(fetchInputJSON(u)), &actool.ToolContext{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return res.Flatten(), res.IsError
+}

agent/worker.go

@@ -482,16 +482,14 @@ func (w *Worker) execute(ctx context.Context, name string, taskID int64, as *db.
 		Provider:        w.prov,
 		SystemPrompt:    system,
 		DynamicBoundary: boundary,
-		Tools:           tools,
+		Tools:           withWebFetch(tools, w.proxyAddr, w.proxyCACert),
 		DeferredTools:   def.Deferred,
 		UnlockSet:       def.Unlock,
 		PermissionMode:  permission.ModeBypass,
-		// WebFetch goes through the recording proxy, so its HTTP is recorded just like
-		// curl; loading the proxy CA lets MITM-re-signed HTTPS certs [verify normally]
-		// (rather than disabling verification). Direct when proxy is empty.
-		EnableWebFetch: true,
-		WebFetchProxy:  w.proxyAddr,
-		WebFetchCACert: w.proxyCACert,
+		// WebFetch (added to Tools above) goes through the recording proxy, so its
+		// HTTP is recorded just like curl; loading the proxy CA lets MITM-re-signed
+		// HTTPS certs [verify normally] (rather than disabling verification). Direct
+		// when proxy is empty. Every redirect hop goes through the target gate.
 		// Web search (optional). ddgs needs no key; brave-free needs BraveKey; tavily needs TavilyKey.
 		// WebSearchProxy is a dedicated egress proxy (http/https/socks5), unrelated to the traffic-recording MITM proxy; empty = direct.
 		EnableWebSearch:       w.webSearch.Enabled,

db/intercept_detail.go

@@ -76,6 +76,9 @@ type InterceptTarget struct {
 	// ExemptVoid: a stored exemption names this target, and did not apply because
 	// the name resolved to a private, loopback or otherwise local address.
 	ExemptVoid bool `json:"exempt_void,omitempty"`
+	// RedirectFrom: the origin (host:port) of the redirect hop that led to this
+	// target; empty when the call named the target itself.
+	RedirectFrom string `json:"redirect_from,omitempty"`
 }
 
 type InterceptDetail struct {

intercept/target_gate.go

@@ -110,6 +110,8 @@ type targetCheck struct {
 	tool  string
 	input []byte
 	urls  []string // the URLs the call declares, as written, for the URL block rules
+	// redirectFrom is the origin (host:port) of a redirect hop; empty for a call.
+	redirectFrom string
 }
 
 // checkedTarget is one target of the call and what the gate learned about it.
@@ -303,6 +305,9 @@ func (c *targetCheck) log(status, reason, configDigest string, targets ...db.Int
 		// The row records that a pin or an exemption was used, not this one call.
 		audit.ExecutionStatus = "unknown"
 	}
+	for n := range targets {
+		targets[n].RedirectFrom = c.redirectFrom
+	}
 	audit.Targets = targets
 	_, agentName := taskInfoFromCtx(c.ctx)
 	_ = c.i.targets.LogDecision(db.TargetDecision{Scope: c.ref, AgentName: agentName, ToolName: c.tool,

intercept/target_redirect.go

@@ -0,0 +1,107 @@
+package intercept
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"net/http"
+)
+
+// The HTTP clients the platform owns (WebFetch and the custom http tool)
+// follow redirects. The hook and the rendered-URL gate decide on the URL a call
+// names; a redirect sends the client to a URL nobody checked. RedirectCheck is
+// the redirect policy of those clients: the client asks it before it follows
+// each hop, and the hop goes through the same target decision as the call, on
+// the URL the client is about to request: the asset block rules on that URL and
+// on its target, before any lookup, then exemptions, resolution and pins.
+
+// maxRedirects is the limit net/http applies to a client without a redirect
+// policy. Setting a policy replaces it, so RedirectCheck restates it, with the
+// same error text.
+const maxRedirects = 10
+
+// RedirectCheck returns the redirect policy (http.Client.CheckRedirect) of a
+// platform-owned client run by the tool toolName. Everything it needs comes
+// from the context of the request, which net/http keeps on every hop: the
+// target scope of the session and the Interceptor that owns its gate.
+//
+// With the gate off, or with no scope in the context (the operator's test
+// endpoint), it only applies the limit of 10 hops: nothing is parsed, resolved,
+// read or written, and the client behaves as with the default policy.
+//
+// A hop no pin or exemption covers is not followed, and the policy never waits:
+// the fetch has its own deadline, which a human decision does not fit in. The
+// request row for the hop's target is found or created (it is durable, so an
+// approval given later lets the retried call follow), and the call fails at
+// once with TARGET_APPROVAL_PENDING. A block rule, a failed lookup or a hop
+// whose target cannot be read fails the call with its block code, and opens no
+// request.
+func RedirectCheck(toolName string) func(req *http.Request, via []*http.Request) error {
+	return func(req *http.Request, via []*http.Request) error {
+		if len(via) >= maxRedirects {
+			return errors.New("stopped after 10 redirects")
+		}
+		ctx := req.Context()
+		scope, on := renderedScope(ctx)
+		if !on {
+			return nil
+		}
+		return checkRedirectHop(ctx, scope, toolName, req.URL.String(), via[len(via)-1].URL.String())
+	}
+}
+
+// checkRedirectHop runs the gate decision on one hop, from the URL that
+// redirected (from) to the URL the client will request (hop).
+func checkRedirectHop(ctx context.Context, scope TargetScope, toolName, hop, from string) error {
+	input, _ := json.Marshal(map[string]string{"url": hop, "redirect_from": from})
+	blocked := func(res TargetResult) error {
+		return &redirectError{res: res, from: from, hop: hop, scope: scope.scopeName()}
+	}
+	t, err := urlTarget(hop)
+	if err != nil {
+		return blocked(undeterminedTarget(ctx, scope, toolName, input, "the target of the redirect could not be read ("+err.Error()+")"))
+	}
+	i := scope.Interceptor
+	if i == nil {
+		return blocked(TargetResult{Code: TargetGateUnavailable, Host: t.Host, Port: t.Port, Reason: "the session's target scope carries no gate"})
+	}
+	var origin string
+	if o, err := urlTarget(from); err == nil {
+		origin = o.String()
+	}
+	ctx = WithCall(ctx, toolName, input)
+	c := &targetCheck{i: i, ctx: ctx, scope: scope, tool: toolName, input: input, urls: []string{hop}, redirectFrom: origin}
+	unpinned, res := c.run([]Target{t})
+	if res.Code == "" && len(unpinned) > 0 {
+		// Wait bound 0: the request is found or created, and the call does not wait.
+		scope.WaitBound = 0
+		for n := range unpinned {
+			unpinned[n].RedirectFrom = origin
+		}
+		res = i.RequestTargets(ctx, scope, toolName, input, unpinned, nil)
+	}
+	if res.Code == "" {
+		return nil
+	}
+	return blocked(res)
+}
+
+// redirectError is what the client returns when a hop is not followed. Both
+// tools hand the client error to the model as the tool result.
+type redirectError struct {
+	res              TargetResult
+	from, hop, scope string
+}
+
+func (e *redirectError) Error() string {
+	target := e.hop
+	if e.res.Host != "" {
+		target = targetName(TargetRequest{Host: e.res.Host, Port: e.res.Port})
+	}
+	msg := "[ARTEX platform control, not target defense] " + e.res.Code + ": " + e.from + " redirects to " + target
+	if e.res.Code == TargetApprovalPending {
+		return msg + ", which is not approved for " + e.scope + ". The redirect was not followed and an approval was requested. " +
+			"Retry the same call after the approval. Do not fetch the redirect target directly or with another tool."
+	}
+	return msg + ": " + e.res.Reason + ". The redirect was not followed. Do not fetch the redirect target directly or with another tool."
+}

intercept/target_redirect_pg_test.go

@@ -0,0 +1,95 @@
+package intercept
+
+import (
+	"strconv"
+	"strings"
+	"testing"
+	"time"
+)
+
+// Step 1.9 against PostgreSQL: a hop no pin covers opens the durable request
+// and fails the call at once; an approval lets the same call follow.
+
+// A hop to an unpinned target is not followed: the redirect target receives
+// nothing, exactly one request row is opened for it, and the call fails with
+// TARGET_APPROVAL_PENDING without waiting, although the scope would wait five
+// minutes at the hook. The same call again attaches to that row. After the
+// approval it follows.
+func TestRedirectToUnpinnedHostNotFollowed(t *testing.T) {
+	d := targetTestDB(t)
+	ic, res := pgGate(t, d)
+	scope := taskScope(t, d, ic, 5*time.Minute)
+	ctx := WithTargetScope(t.Context(), scope)
+	final, finalHits, finalKey := hopServer(t, "")
+	start, startHits, startKey := hopServer(t, final.URL+"/final")
+
+	began := time.Now()
+	_, err := gatedFetch(ctx, start.URL+"/start")
+	if err == nil || !strings.Contains(err.Error(), TargetApprovalPending) ||
+		!strings.Contains(err.Error(), start.URL+"/start redirects to "+finalKey) || !strings.Contains(err.Error(), "not followed") {
+		t.Fatalf("unpinned hop: %v", err)
+	}
+	if elapsed := time.Since(began); elapsed > 10*time.Second {
+		t.Fatalf("the hop waited %v", elapsed)
+	}
+	if startHits.Load() != 1 || finalHits.Load() != 0 {
+		t.Fatalf("hits start=%d final=%d, want the redirect target untouched", startHits.Load(), finalHits.Load())
+	}
+	ids := openRows(t, d, scope)
+	if len(ids) != 1 || allRows(t, d, scope) != 1 {
+		t.Fatalf("open requests = %v (%d rows), want one", ids, allRows(t, d, scope))
+	}
+	detail, err := d.GetInterceptDetail(ids[0])
+	if err != nil || detail == nil || detail.Audit == nil || len(detail.Audit.Targets) != 1 {
+		t.Fatalf("request detail = %+v, %v", detail, err)
+	}
+	if tgt := detail.Audit.Targets[0]; tgt.Host+":"+strconv.Itoa(tgt.Port) != finalKey || tgt.RedirectFrom != startKey || tgt.Outcome != "requested" {
+		t.Fatalf("requested target = %+v, want %s from %s", tgt, finalKey, startKey)
+	}
+	if !strings.Contains(detail.Reason, "A redirect from "+startKey) || !strings.Contains(string(detail.ToolInput), start.URL+"/start") {
+		t.Fatalf("request reason %q / input %s, want the origin of the redirect", detail.Reason, detail.ToolInput)
+	}
+
+	// The retried call stops at the same hop and attaches to the same row.
+	if _, err := gatedFetch(ctx, start.URL+"/start"); err == nil || !strings.Contains(err.Error(), TargetApprovalPending) || finalHits.Load() != 0 {
+		t.Fatalf("retry before the approval: %v, final hits %d", err, finalHits.Load())
+	}
+	if again := openRows(t, d, scope); len(again) != 1 || again[0] != ids[0] || allRows(t, d, scope) != 1 {
+		t.Fatalf("after the retry: open %v, %d rows; want the same single request", again, allRows(t, d, scope))
+	}
+
+	approveAll(t, d, ic, scope)
+	if resp, err := gatedFetch(ctx, start.URL+"/start"); err != nil || resp.StatusCode != 200 || finalHits.Load() != 1 {
+		t.Fatalf("after the approval: %v, final hits %d", err, finalHits.Load())
+	}
+	if res.total() != 0 {
+		t.Fatalf("%d lookups for IP literals", res.total())
+	}
+}
+
+// http -> https on the same host is another key (port 443, not 80): a pin on
+// (host, 80) does not cover it, and the hop asks again.
+func TestRedirectHTTPToHTTPSAsksAgain(t *testing.T) {
+	d := targetTestDB(t)
+	ic, res := pgGate(t, d)
+	res.set("app.example.com", "203.0.113.7")
+	scope := taskScope(t, d, ic, time.Minute)
+	pinURL(t, d, ic, scope, "http://app.example.com/")
+	ctx := WithTargetScope(t.Context(), scope)
+
+	if err := hop(ctx, "http://app.example.com/next", "http://app.example.com/"); err != nil {
+		t.Fatalf("hop on the pinned key: %v", err)
+	}
+	err := hop(ctx, "https://app.example.com/", "http://app.example.com/")
+	if err == nil || !strings.Contains(err.Error(), TargetApprovalPending) || !strings.Contains(err.Error(), "redirects to app.example.com:443") {
+		t.Fatalf("http -> https: %v", err)
+	}
+	ids := openRows(t, d, scope)
+	if len(ids) != 1 {
+		t.Fatalf("open requests = %v, want the one for port 443", ids)
+	}
+	detail, err := d.GetInterceptDetail(ids[0])
+	if err != nil || detail == nil || detail.Audit == nil || detail.Audit.Targets[0].Port != 443 || detail.Audit.Targets[0].RedirectFrom != "app.example.com:80" {
+		t.Fatalf("request = %+v, %v", detail, err)
+	}
+}

intercept/target_redirect_test.go

@@ -0,0 +1,229 @@
+package intercept
+
+import (
+	"context"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/Autumn-27/artex/db"
+)
+
+// Step 1.9: every redirect hop of a platform-owned client goes through the gate.
+// Without a database: a hop that would open a request is covered by the
+// PostgreSQL tests.
+
+// hopServer counts its requests and answers a fixed page, or a redirect to
+// location when it is set.
+func hopServer(t *testing.T, location string) (srv *httptest.Server, hits *atomic.Int64, key string) {
+	t.Helper()
+	hits = &atomic.Int64{}
+	srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		hits.Add(1)
+		if location != "" {
+			http.Redirect(w, r, location, http.StatusFound)
+			return
+		}
+		_, _ = w.Write([]byte("hop-reached"))
+	}))
+	t.Cleanup(srv.Close)
+	u, err := url.Parse(srv.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return srv, hits, u.Host
+}
+
+// hop calls the redirect policy of tool on one hop, as the client does.
+func hop(ctx context.Context, to string, from ...string) error {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, to, nil)
+	if err != nil {
+		panic(err)
+	}
+	via := make([]*http.Request, len(from))
+	for n, f := range from {
+		if via[n], err = http.NewRequestWithContext(ctx, http.MethodGet, f, nil); err != nil {
+			panic(err)
+		}
+	}
+	return RedirectCheck("WebFetch")(req, via)
+}
+
+func gatedFetch(ctx context.Context, rawURL string) (*http.Response, error) {
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, rawURL, nil)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := (&http.Client{CheckRedirect: RedirectCheck("WebFetch")}).Do(req)
+	if resp != nil {
+		resp.Body.Close()
+	}
+	return resp, err
+}
+
+// With the gate off, or without a scope, the policy is net/http's default:
+// every hop is followed, up to 10, with the same error after that. Nothing is
+// parsed, resolved, read or logged, not even a hop whose target cannot be read.
+func TestRedirectGateOffKeepsDefaultPolicy(t *testing.T) {
+	g := newGate(t)
+	g.res.set("app.example.com", "203.0.113.7")
+	chain := make([]string, maxRedirects)
+	for n := range chain {
+		chain[n] = "http://app.example.com/"
+	}
+	for name, ctx := range map[string]context.Context{
+		"no scope": context.Background(),
+		"no flag":  WithTargetScope(context.Background(), TargetScope{TaskID: "7", WaitBound: time.Minute, Interceptor: g.ic}),
+		"flag off": WithTargetScope(context.Background(), TargetScope{TaskID: "7", Enabled: func() bool { return false }, Interceptor: g.ic}),
+	} {
+		if err := hop(ctx, "https://other.example.com/", chain[:1]...); err != nil {
+			t.Errorf("%s: %v, want the hop followed", name, err)
+		}
+		if err := hop(ctx, "http:///no-host", chain[:1]...); err != nil {
+			t.Errorf("%s, no host: %v, want the hop followed", name, err)
+		}
+		if err := hop(ctx, "https://other.example.com/", chain[:maxRedirects-1]...); err != nil {
+			t.Errorf("%s, hop 9: %v", name, err)
+		}
+		if err := hop(ctx, "https://other.example.com/", chain...); err == nil || err.Error() != "stopped after 10 redirects" {
+			t.Errorf("%s, hop 10: %v, want net/http's limit", name, err)
+		}
+
+		// Through a real client: a hop to another port, which the gate would ask
+		// for, is followed.
+		final, finalHits, _ := hopServer(t, "")
+		start, _, _ := hopServer(t, final.URL+"/final")
+		if resp, err := gatedFetch(ctx, start.URL+"/start"); err != nil || resp.StatusCode != http.StatusOK || finalHits.Load() != 1 {
+			t.Errorf("%s: chain not followed: %v, hits=%d", name, err, finalHits.Load())
+		}
+		loop := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			http.Redirect(w, r, r.URL.Path+"x", http.StatusFound)
+		}))
+		_, gotErr := gatedFetch(ctx, loop.URL+"/l")
+		_, wantErr := (&http.Client{}).Get(loop.URL + "/l")
+		loop.Close()
+		if gotErr == nil || wantErr == nil || gotErr.Error() != wantErr.Error() {
+			t.Errorf("%s: redirect loop: %v, want the default policy's %v", name, gotErr, wantErr)
+		}
+	}
+	if g.store.reads != 0 || len(g.store.logged) != 0 || g.res.total() != 0 {
+		t.Errorf("gate off: %d store reads, %d rows, %d lookups, want none", g.store.reads, len(g.store.logged), g.res.total())
+	}
+	// Gate on, the limit holds as well, before anything is read.
+	if err := hop(g.ctx(), "https://app.example.com/", chain...); err == nil || err.Error() != "stopped after 10 redirects" || g.store.reads != 0 {
+		t.Errorf("gate on, hop 10: %v, %d store reads", err, g.store.reads)
+	}
+}
+
+// A hop to a pinned target is followed, through a real client: the redirected
+// request keeps the context of the call, so the policy finds the scope. The
+// first use of the pin is logged with the origin of the redirect.
+func TestRedirectToPinnedHostFollowed(t *testing.T) {
+	g := newGate(t)
+	final, finalHits, finalKey := hopServer(t, "")
+	start, startHits, startKey := hopServer(t, final.URL+"/final")
+	host, port, _ := net.SplitHostPort(finalKey)
+	pin := &db.TargetPin{ID: 1, Host: host, Port: atoiPort(t, port), Version: 1, Status: db.TargetPinActive, PinnedIPs: []string{host}}
+	g.store.pins = []*db.TargetPin{pin}
+
+	resp, err := gatedFetch(g.ctx(), start.URL+"/start")
+	if err != nil || resp.StatusCode != http.StatusOK || startHits.Load() != 1 || finalHits.Load() != 1 {
+		t.Fatalf("pinned hop: %v, hits start=%d final=%d", err, startHits.Load(), finalHits.Load())
+	}
+	if got := g.store.outcomes(); len(got) != 1 || got[0] != "allowed/pin_match" {
+		t.Fatalf("rows = %v, want the first use of the pin", got)
+	}
+	row := g.store.logged[0]
+	if tgt := row.Audit.Targets[0]; tgt.Host != host || tgt.RedirectFrom != startKey || tgt.PinID != pin.ID {
+		t.Fatalf("logged target = %+v, want %s from %s", tgt, finalKey, startKey)
+	}
+	if !strings.Contains(string(row.ToolInput), final.URL+"/final") || !strings.Contains(string(row.ToolInput), start.URL+"/start") {
+		t.Fatalf("logged input = %s, want the hop and its origin", row.ToolInput)
+	}
+	if g.res.total() != 0 {
+		t.Fatalf("%d lookups for an IP literal", g.res.total())
+	}
+}
+
+// A (host, 0) pin covers every port: http -> https on that host is followed.
+func TestRedirectToPortZeroPinnedHostFollowed(t *testing.T) {
+	g := newGate(t)
+	g.res.set("app.example.com", "203.0.113.7")
+	g.store.pins = []*db.TargetPin{{ID: 1, Host: "app.example.com", Port: 0, Version: 1, Status: db.TargetPinActive, PinnedIPs: []string{"203.0.113.7"}}}
+	if err := hop(g.ctx(), "https://app.example.com/login", "http://app.example.com/login"); err != nil {
+		t.Fatalf("http -> https under a (host, 0) pin: %v", err)
+	}
+}
+
+// A block rule stops a hop before anything is resolved, whether it names the
+// hop's host or its URL, and even when the hop stays on a pinned host. No
+// request is opened.
+func TestRedirectToBlockedNameNotResolved(t *testing.T) {
+	g := newGate(t)
+	g.res.set("app.example.com", "203.0.113.7")
+	g.res.set("evil.example", "198.51.100.9")
+	g.store.pins = []*db.TargetPin{{ID: 1, Host: "app.example.com", Port: 443, Version: 1, Status: db.TargetPinActive, PinnedIPs: []string{"203.0.113.7"}}}
+	g.store.rules = []db.AssetInterceptRule{
+		{Enabled: true, Kind: "exact_domain", Pattern: "evil.example"},
+		{Enabled: true, Kind: "exact_url", Pattern: "https://app.example.com/admin"},
+	}
+
+	err := hop(g.ctx(), "http://evil.example/x", "https://app.example.com/")
+	if err == nil || !strings.Contains(err.Error(), TargetRuleBlocked) || !strings.Contains(err.Error(), "https://app.example.com/ redirects to evil.example:80") {
+		t.Fatalf("hop to a blocked name: %v", err)
+	}
+	if n := g.res.lookups("evil.example"); n != 0 {
+		t.Fatalf("the blocked name was resolved %d times", n)
+	}
+	err = hop(g.ctx(), "https://app.example.com/admin", "https://app.example.com/")
+	if err == nil || !strings.Contains(err.Error(), TargetRuleBlocked) {
+		t.Fatalf("hop to a blocked URL on a pinned host: %v", err)
+	}
+	if got := g.store.outcomes(); len(got) != 2 || got[0] != "denied/rule_blocked" || got[1] != "denied/rule_blocked" {
+		t.Fatalf("rows = %v, want two blocks", got)
+	}
+	if from := g.store.logged[0].Audit.Targets[0].RedirectFrom; from != "app.example.com:443" {
+		t.Fatalf("redirect_from = %q", from)
+	}
+	if g.res.total() != 0 {
+		t.Fatalf("%d lookups, want none", g.res.total())
+	}
+}
+
+// A hop whose target cannot be read is blocked with TARGET_GATE_UNAVAILABLE, as
+// a rendered URL is, and opens no request.
+func TestRedirectUnreadableHopBlocked(t *testing.T) {
+	g := newGate(t)
+	for _, to := range []*url.URL{
+		{Scheme: "http", Path: "/no-host"},
+		{Scheme: "http", Host: "app.example.com:99999", Path: "/"},
+	} {
+		req, _ := http.NewRequestWithContext(g.ctx(), http.MethodGet, "http://placeholder.example/", nil)
+		req.URL = to
+		via, _ := http.NewRequestWithContext(g.ctx(), http.MethodGet, "https://app.example.com/", nil)
+		err := RedirectCheck("WebFetch")(req, []*http.Request{via})
+		if err == nil || !strings.Contains(err.Error(), TargetGateUnavailable) {
+			t.Errorf("%s: %v, want TARGET_GATE_UNAVAILABLE", to, err)
+		}
+	}
+	if got := g.store.outcomes(); len(got) != 2 || got[0] != "denied/gate_unavailable" {
+		t.Fatalf("rows = %v", got)
+	}
+	if g.res.total() != 0 {
+		t.Fatalf("%d lookups, want none", g.res.total())
+	}
+}
+
+func atoiPort(t *testing.T, s string) int {
+	t.Helper()
+	p := validPort(s)
+	if p == 0 {
+		t.Fatalf("port %q", s)
+	}
+	return p
+}

intercept/target_request.go

@@ -41,6 +41,9 @@ type TargetRequest struct {
 	Reason      string        // no_pin | new_ip | revoked
 	Pin         *db.TargetPin // the active pin an approval would extend (new_ip); nil otherwise
 	ExemptVoid  bool          // a stored exemption names the target and was void for this call
+	// RedirectFrom is the origin (host:port) of the redirect that leads to the
+	// target; empty when the call names the target itself.
+	RedirectFrom string
 }
 
 // TargetResult is the outcome of RequestTargets. Code is empty when every
@@ -248,6 +251,7 @@ func (i *Interceptor) openTargetRequest(ctx context.Context, ref db.TargetScopeR
 		Host: t.Host, Port: t.Port, Kind: t.Kind,
 		ResolvedIPs: t.ResolvedIPs, Resolver: t.Resolver, ResolvedAt: t.ResolvedAt,
 		Reason: t.Reason, Outcome: "requested", NameOnlyEffective: nameOnly, ExemptVoid: t.ExemptVoid,
+		RedirectFrom: t.RedirectFrom,
 	}
 	if t.Pin != nil {
 		target.PinID, target.PinVersion, target.PinnedIPs = t.Pin.ID, t.Pin.Version, t.Pin.PinnedIPs
@@ -363,6 +367,9 @@ func targetReason(scope TargetScope, t TargetRequest, ask *Decision, nameOnly bo
 		b.WriteString(ask.Message)
 		b.WriteString("\nThis call also names a target that needs approval. ")
 	}
+	if t.RedirectFrom != "" {
+		fmt.Fprintf(&b, "A redirect from %s leads to this target; the redirect was not followed. ", t.RedirectFrom)
+	}
 	name, bound := targetName(t), scope.scopeName()
 	if t.Port == 0 {
 		name += " (port not declared: every port)"

server/customtool.go

@@ -455,6 +455,8 @@ func (s *Server) runHTTPTool(ctx context.Context, key string, execRaw json.RawMe
 		req.Header.Set(k, renderTemplate(v, params, identity))
 	}
 	client := &http.Client{Timeout: timeoutOr(spec.TimeoutMs, 30000)}
+	// Every redirect hop goes through the target gate, as the rendered URL did.
+	client.CheckRedirect = intercept.RedirectCheck(key)
 	if tr := s.httpProxyTransport(spec); tr != nil {
 		client.Transport = tr
 	}

server/target_redirect_test.go

@@ -0,0 +1,162 @@
+package server
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/Autumn-27/artex/db"
+)
+
+// Step 1.9: the redirect hops of the custom http tool and of a worker's
+// WebFetch go through the target gate.
+
+// redirectingServer answers every request with a redirect to location and
+// counts the requests. Its host:port is an IP literal: the gate never resolves it.
+func redirectingServer(t *testing.T, location string) (srv *httptest.Server, hits *atomic.Int64, key string) {
+	t.Helper()
+	hits = &atomic.Int64{}
+	srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		hits.Add(1)
+		http.Redirect(w, r, location, http.StatusFound)
+	}))
+	t.Cleanup(srv.Close)
+	return srv, hits, srv.Listener.Addr().String()
+}
+
+func decide(t *testing.T, g *gateServer, id int64, decision string) {
+	t.Helper()
+	if code, body := g.do(t, "POST", fmt.Sprintf("/api/intercept/pending/%d/decide", id), `{"decision":"`+decision+`"}`); code != 200 {
+		t.Fatalf("decide %d: %d %v", id, code, body)
+	}
+}
+
+// A custom http tool whose rendered URL is pinned, and which redirects to a
+// target no pin covers: the hop is not followed, one request is opened for its
+// target, and the call fails at once. After the approval the same call follows.
+func TestCustomHTTPRedirectTargetGated(t *testing.T) {
+	g := newGateServer(t)
+	on := true
+	task := g.newTask(t, db.TaskCreateOptions{TargetGate: &on})
+	pg := g.m.pg
+	final, finalHits, fhost, fport := countingServer(t)
+	finalKey := net.JoinHostPort(fhost, fport)
+	start, startHits, startKey := redirectingServer(t, final.URL+"/final")
+
+	tool := g.s.buildCustomTool(&db.Tool{Key: "probe_redirect", Kind: "http",
+		Exec: execJSON(t, map[string]any{"method": "GET", "url": start.URL + "/start"})})
+	// The rendered URL itself first: its request, approved.
+	if out, isErr := callTool(t, tool, gatedCtx(task, 0), `{}`, nil); !isErr || !strings.Contains(out, "TARGET_APPROVAL_PENDING") || startHits.Load() != 0 {
+		t.Fatalf("rendered URL: error=%v out=%q", isErr, out)
+	}
+	id, _, _, ok := openTargetRequest(t, pg, task.ID, startKey)
+	if !ok {
+		t.Fatal("no request for the rendered URL")
+	}
+	decide(t, g, id, "allowed")
+
+	// The wait bound is long: the hop must not use it.
+	began := time.Now()
+	out, isErr := callTool(t, tool, gatedCtx(task, time.Minute), `{}`, nil)
+	if !isErr || !strings.Contains(out, "TARGET_APPROVAL_PENDING") || !strings.Contains(out, start.URL+"/start redirects to "+finalKey) {
+		t.Fatalf("redirect to an unpinned target: error=%v out=%q", isErr, out)
+	}
+	if elapsed := time.Since(began); elapsed > 10*time.Second {
+		t.Fatalf("the hop waited %v", elapsed)
+	}
+	if startHits.Load() != 1 || finalHits.Load() != 0 {
+		t.Fatalf("hits origin=%d target=%d, want the target untouched", startHits.Load(), finalHits.Load())
+	}
+	hopID, toolName, toolInput, ok := openTargetRequest(t, pg, task.ID, finalKey)
+	if !ok || toolName != "probe_redirect" || !strings.Contains(toolInput, final.URL+"/final") || !strings.Contains(toolInput, start.URL+"/start") {
+		t.Fatalf("request for the hop: ok=%v tool=%q input=%s", ok, toolName, toolInput)
+	}
+	var requests int
+	if err := pg.QueryRow(`SELECT count(*) FROM intercept_pending WHERE task_id=$1 AND target_key IS NOT NULL`, task.ID).Scan(&requests); err != nil || requests != 2 {
+		t.Fatalf("%d requests, %v; want the origin's and the hop's", requests, err)
+	}
+
+	decide(t, g, hopID, "allowed")
+	if out, isErr := callTool(t, tool, gatedCtx(task, 0), `{}`, nil); isErr || !strings.Contains(out, "probe-reached") || finalHits.Load() != 1 {
+		t.Fatalf("after the approval: error=%v out=%q target hits=%d", isErr, out, finalHits.Load())
+	}
+}
+
+// The custom-tool test endpoint has no approval scope (D14): its redirects are
+// followed as before, and nothing is written.
+func TestCustomToolTestEndpointRedirectUngated(t *testing.T) {
+	g := newGateServer(t)
+	on := true
+	g.newTask(t, db.TaskCreateOptions{TargetGate: &on})
+	final, finalHits, _, _ := countingServer(t)
+	start, _, _ := redirectingServer(t, final.URL+"/final")
+	count := func() int {
+		var n int
+		if err := g.m.pg.QueryRow(`SELECT count(*) FROM intercept_pending WHERE decision_source='target' OR target_key IS NOT NULL`).Scan(&n); err != nil {
+			t.Fatal(err)
+		}
+		return n
+	}
+	before := count()
+	code, out := g.do(t, "POST", "/api/tools/custom/test", fmt.Sprintf(`{"kind":"http","exec":{"url":%q}}`, start.URL+"/start"))
+	if code != 200 || out["is_error"] != false || !strings.Contains(fmt.Sprint(out["output"]), "probe-reached") || finalHits.Load() != 1 {
+		t.Fatalf("test endpoint: %d %v target hits=%d", code, out, finalHits.Load())
+	}
+	if after := count(); after != before {
+		t.Fatalf("the test endpoint wrote %d target rows", after-before)
+	}
+}
+
+// A gated worker's WebFetch end to end: the origin is approved at the hook, the
+// redirect stops at the hop with TARGET_APPROVAL_PENDING and leaves one request
+// open; once it is approved through the API, the same call follows.
+func TestRedirectRequestSurvivesAndRetryPasses(t *testing.T) {
+	g := newGateServer(t)
+	on := true
+	task := g.newTask(t, db.TaskCreateOptions{TargetGate: &on})
+	pg := g.m.pg
+	final, finalHits, fhost, fport := countingServer(t)
+	finalKey := net.JoinHostPort(fhost, fport)
+	start, startHits, startKey := redirectingServer(t, final.URL+"/final")
+	p := &toolScript{calls: fetches(start.URL+"/start", start.URL+"/start"), results: make(chan string, 16),
+		hold: map[int64]chan struct{}{2: make(chan struct{})}}
+	done := runScriptedWorker(t, g, task, p)
+
+	var id int64
+	waitUntil(t, "the request for the origin", func() bool {
+		var ok bool
+		id, _, _, ok = openTargetRequest(t, pg, task.ID, startKey)
+		return ok
+	})
+	decide(t, g, id, "allowed")
+	if r := p.next(t); !strings.Contains(r, "TARGET_APPROVAL_PENDING") || !strings.Contains(r, "redirects to "+finalKey) {
+		t.Fatalf("first call: %q", r)
+	}
+	if startHits.Load() != 1 || finalHits.Load() != 0 {
+		t.Fatalf("hits origin=%d target=%d, want the target untouched", startHits.Load(), finalHits.Load())
+	}
+	hopID, toolName, _, ok := openTargetRequest(t, pg, task.ID, finalKey)
+	if !ok || toolName != "WebFetch" {
+		t.Fatalf("request for the hop: ok=%v tool=%q", ok, toolName)
+	}
+	detail, err := pg.GetInterceptDetail(hopID)
+	if err != nil || detail == nil || detail.Audit == nil || len(detail.Audit.Targets) != 1 || detail.Audit.Targets[0].RedirectFrom != startKey {
+		t.Fatalf("hop request detail = %+v, %v", detail, err)
+	}
+
+	decide(t, g, hopID, "allowed")
+	close(p.hold[2])
+	if r := p.next(t); !strings.Contains(r, "probe-reached") || finalHits.Load() != 1 {
+		t.Fatalf("the same call after the approval: %q target hits=%d", r, finalHits.Load())
+	}
+	select {
+	case <-done:
+	case <-time.After(60 * time.Second):
+		t.Fatal("the worker run did not end")
+	}
+}