[e2e] guardrail blocks the unselected model for path-routed providers

Add an always-on (no-credentials) e2e regression guard for the report
that a model-allowlist guardrail attached to a policy has no effect for
PATH-ROUTED providers, where the model travels in the URL rather than the
JSON body: Google Vertex (…/models/{model}:rawPredict) and AWS Bedrock
(/model/{id}/invoke).

Each provider is tested in isolation: its own provider, its own guardrail
whose allowlist holds only that provider's allowed model, and its own
policy — so the guardrail the proxy enforces is never a mixed
cross-provider list. Over the tunnel, the allowed model (in the URL path)
is served 200 and an unselected model is denied 403 by the guardrail
(llm_policy.model_blocked) before the upstream. The Vertex case mirrors
the customer verbatim (allow Sonnet; the unselected model is the exact
claude-opus-4-6 they reported reaching unblocked); the Bedrock case sends
a region-prefixed, versioned inference-profile id so URL-path model
normalization is exercised too.

The provider is catch-all, so the router forwards any model and a 403 can
only be the guardrail, never model_not_routable. Only the upstream LLM is
mocked (the vLLM nginx answers any path 200); management synth/reconcile,
the proxy middleware chain (URL-path model extraction, router, guardrail)
and the tunnel are all real, and the guardrail denies before the upstream
is dialed so the mock cannot influence the block. A static bearer api key
makes the router inject a static Authorization header instead of minting a
GCP token, so the test runs with no credentials and always executes.

e2e/agentnetwork/guardrail_block_test.go

@@ -0,0 +1,209 @@
+//go:build e2e
+
+package agentnetwork
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
+	"github.com/netbirdio/netbird/e2e/harness"
+	"github.com/netbirdio/netbird/shared/management/http/api"
+)
+
+// pathRoutedGuardrailCase is one provider's self-contained scenario: its own
+// provider, its own guardrail whose allowlist holds ONLY that provider's
+// allowed model, and its own policy. Each case runs in isolation (its own
+// proxy + client), so the guardrail the proxy enforces contains exactly this
+// provider's model — never a mixed cross-provider list.
+type pathRoutedGuardrailCase struct {
+	name       string
+	catalogID  string // agent-network catalog provider id
+	wire       string // harness.WireVertex | harness.WireBedrock
+	allowEntry string // the single model id put on the guardrail allowlist
+	allowModel string // model id sent that MUST be served (200)
+	blockModel string // model id sent that MUST be denied (403 model_blocked)
+}
+
+// TestGuardrailBlocksUnselectedModel_PathRouted is the end-to-end regression
+// guard for the customer report that a model-allowlist guardrail attached to a
+// policy has no effect for PATH-ROUTED providers — where the model travels in
+// the URL, not the JSON body: Google Vertex (…/models/{model}:rawPredict) and
+// AWS Bedrock (/model/{id}/invoke).
+//
+// Each provider is tested in isolation with a guardrail allowlisting a single
+// model of its own: the allowed model (in the URL path) is served (200) and an
+// unselected model (in the URL path) is denied 403 by the guardrail
+// (llm_policy.model_blocked) before the upstream. The Vertex case mirrors the
+// customer verbatim — allow Sonnet, and the unselected model is the exact
+// claude-opus-4-6 they reported reaching the model unblocked. The Bedrock case
+// sends a region-prefixed, versioned inference-profile id so URL-path model
+// normalization is exercised too.
+//
+// The provider is catch-all (no models), so the router forwards any model and a
+// 403 can only come from the guardrail, never model_not_routable. Only the
+// upstream LLM is mocked (the vLLM nginx answers any path with 200); management
+// synth/reconcile, the proxy middleware chain (URL-path model extraction,
+// router, guardrail) and the tunnel are all real, and the guardrail denies
+// before the upstream is dialed so the mock cannot influence the block. A
+// static bearer api key is used so the router injects a static Authorization
+// header instead of minting a GCP token — the only reason path-routed providers
+// normally need live credentials — so the test runs with none and is always on.
+func TestGuardrailBlocksUnselectedModel_PathRouted(t *testing.T) {
+	cases := []pathRoutedGuardrailCase{
+		{
+			name:       "vertex",
+			catalogID:  "vertex_ai_api",
+			wire:       harness.WireVertex,
+			allowEntry: "claude-sonnet-4-5",
+			allowModel: "claude-sonnet-4-5",
+			blockModel: "claude-opus-4-6", // the customer-reported model
+		},
+		{
+			name:       "bedrock",
+			catalogID:  "bedrock_api",
+			wire:       harness.WireBedrock,
+			allowEntry: "anthropic.claude-sonnet-4-5", // normalized catalog id
+			allowModel: "us.anthropic.claude-sonnet-4-5-v1:0",
+			blockModel: "us.anthropic.claude-opus-4-8-v1:0",
+		},
+	}
+
+	for _, tc := range cases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			runPathRoutedGuardrailCase(t, tc)
+		})
+	}
+}
+
+func runPathRoutedGuardrailCase(t *testing.T, tc pathRoutedGuardrailCase) {
+	t.Helper()
+
+	const (
+		vertexProject = "e2e-project"
+		vertexRegion  = "global"
+	)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 15*time.Minute)
+	defer cancel()
+
+	vllm, err := harness.StartVLLM(ctx, srv)
+	require.NoError(t, err, "start mock upstream")
+	t.Cleanup(func() { _ = vllm.Terminate(context.Background()) })
+
+	grp, err := srv.API().Groups.Create(ctx, api.PostApiGroupsJSONRequestBody{Name: "e2e-guardrail-" + tc.name})
+	require.NoError(t, err, "create group")
+	t.Cleanup(func() { _ = srv.API().Groups.Delete(context.Background(), grp.Id) })
+
+	ephemeral := false
+	sk, err := srv.API().SetupKeys.Create(ctx, api.PostApiSetupKeysJSONRequestBody{
+		Name:       "e2e-guardrail-" + tc.name + "-client",
+		Type:       "reusable",
+		ExpiresIn:  86400,
+		UsageLimit: 0,
+		AutoGroups: []string{grp.Id},
+		Ephemeral:  &ephemeral,
+	})
+	require.NoError(t, err, "mint setup key")
+	require.NotEmpty(t, sk.Key, "setup key plaintext")
+
+	// Catch-all provider (no models) so the router forwards any model; a static
+	// bearer key means the router injects a static auth header instead of minting
+	// a GCP token. Bootstraps the cluster if it isn't already.
+	staticKey := "static-e2e-token"
+	prov, err := srv.CreateProvider(ctx, api.AgentNetworkProviderRequest{
+		Name:             tc.name,
+		ProviderId:       tc.catalogID,
+		UpstreamUrl:      vllm.URL,
+		ApiKey:           &staticKey,
+		Enabled:          ptr(true),
+		BootstrapCluster: ptr(harness.AgentNetworkCluster),
+	})
+	require.NoError(t, err, "create %s provider", tc.name)
+	t.Cleanup(func() { _ = srv.DeleteProvider(context.Background(), prov.Id) })
+
+	// Guardrail allowlisting ONLY this provider's allowed model.
+	var gr api.AgentNetworkGuardrailRequest
+	gr.Name = "e2e-guardrail-" + tc.name
+	gr.Checks.ModelAllowlist.Enabled = true
+	gr.Checks.ModelAllowlist.Models = []string{tc.allowEntry}
+	guard, err := srv.CreateGuardrail(ctx, gr)
+	require.NoError(t, err, "create guardrail")
+	t.Cleanup(func() { _ = srv.DeleteGuardrail(context.Background(), guard.Id) })
+
+	enabled := true
+	pol, err := srv.CreatePolicy(ctx, api.AgentNetworkPolicyRequest{
+		Name:                   "e2e-guardrail-" + tc.name,
+		Enabled:                &enabled,
+		SourceGroups:           []string{grp.Id},
+		DestinationProviderIds: []string{prov.Id},
+		GuardrailIds:           &[]string{guard.Id},
+	})
+	require.NoError(t, err, "create policy")
+	t.Cleanup(func() { _ = srv.DeletePolicy(context.Background(), pol.Id) })
+
+	settings, err := srv.GetSettings(ctx)
+	require.NoError(t, err, "read settings")
+	require.NotEmpty(t, settings.Endpoint, "endpoint must be assigned")
+
+	proxyToken, err := srv.CreateProxyTokenCLI(ctx, "e2e-guardrail-"+tc.name+"-proxy")
+	require.NoError(t, err, "mint proxy token")
+	px, err := harness.StartProxy(ctx, srv, proxyToken)
+	require.NoError(t, err, "start proxy")
+	t.Cleanup(func() { _ = px.Terminate(context.Background()) })
+
+	cl, err := harness.StartClient(ctx, srv, sk.Key)
+	require.NoError(t, err, "start client")
+	t.Cleanup(func() { _ = cl.Terminate(context.Background()) })
+
+	require.NoError(t, cl.WaitConnected(ctx, 90*time.Second), "client must connect to management")
+	// Probe first: the GET resolves the endpoint and its first packet wakes the
+	// lazy proxy peer, so WaitProxyPeer then observes it connected.
+	proxyIP, err := cl.ResolveProxyIP(ctx, settings.Endpoint)
+	require.NoError(t, err, "resolve endpoint to proxy IP")
+	if err := cl.WaitProxyPeer(ctx, 180*time.Second); err != nil {
+		t.Fatalf("client did not see the proxy peer: %v\n=== proxy logs ===\n%s", err, px.Logs(context.Background()))
+	}
+
+	send := func(model string) (int, string) {
+		var code int
+		var body string
+		var cerr error
+		switch tc.wire {
+		case harness.WireVertex:
+			code, body, cerr = cl.Vertex(ctx, settings.Endpoint, proxyIP, vertexProject, vertexRegion, model, "Reply with exactly: pong", "")
+		case harness.WireBedrock:
+			code, body, cerr = cl.Bedrock(ctx, settings.Endpoint, proxyIP, model, "Reply with exactly: pong", "")
+		default:
+			t.Fatalf("unsupported wire %q", tc.wire)
+		}
+		require.NoError(t, cerr, "request must reach the proxy for %s", tc.name)
+		return code, body
+	}
+
+	// Allowed model (in the URL path) is served. Retry to absorb tunnel/DNS
+	// jitter on the first call over the freshly warmed tunnel.
+	var code int
+	var body string
+	deadline := time.Now().Add(90 * time.Second)
+	for time.Now().Before(deadline) {
+		code, body = send(tc.allowModel)
+		if code == 200 {
+			break
+		}
+		time.Sleep(5 * time.Second)
+	}
+	assert.Equal(t, 200, code,
+		"allowed %s model (URL path) must be served; body: %s\n=== proxy logs ===\n%s", tc.name, body, px.Logs(context.Background()))
+
+	// Unselected model (in the URL path) must be blocked by the guardrail.
+	code, body = send(tc.blockModel)
+	assert.Equal(t, 403, code,
+		"unselected %s model (URL path) must be denied, not served; body: %s\n=== proxy logs ===\n%s", tc.name, body, px.Logs(context.Background()))
+	assert.Contains(t, body, "llm_policy.model_blocked",
+		"%s denial must come from the guardrail allowlist, not routing; body: %s", tc.name, body)
+}