meshcore-analyzer/cmd/server/decoder_test.go

package main

import (
	"crypto/ed25519"
	"encoding/binary"
	"encoding/hex"
	"testing"
)

func TestDecodeHeader_TransportFlood(t *testing.T) {
	// Route type 0 = TRANSPORT_FLOOD, payload type 5 = GRP_TXT, version 0
	// Header byte: (0 << 6) | (5 << 2) | 0 = 0x14
	h := decodeHeader(0x14)
	if h.RouteType != RouteTransportFlood {
		t.Errorf("expected RouteTransportFlood (0), got %d", h.RouteType)
	}
	if h.RouteTypeName != "TRANSPORT_FLOOD" {
		t.Errorf("expected TRANSPORT_FLOOD, got %s", h.RouteTypeName)
	}
	if h.PayloadType != PayloadGRP_TXT {
		t.Errorf("expected PayloadGRP_TXT (5), got %d", h.PayloadType)
	}
}

func TestDecodeHeader_TransportDirect(t *testing.T) {
	// Route type 3 = TRANSPORT_DIRECT, payload type 2 = TXT_MSG, version 0
	// Header byte: (0 << 6) | (2 << 2) | 3 = 0x0B
	h := decodeHeader(0x0B)
	if h.RouteType != RouteTransportDirect {
		t.Errorf("expected RouteTransportDirect (3), got %d", h.RouteType)
	}
	if h.RouteTypeName != "TRANSPORT_DIRECT" {
		t.Errorf("expected TRANSPORT_DIRECT, got %s", h.RouteTypeName)
	}
}

func TestDecodeHeader_Flood(t *testing.T) {
	// Route type 1 = FLOOD, payload type 4 = ADVERT
	// Header byte: (0 << 6) | (4 << 2) | 1 = 0x11
	h := decodeHeader(0x11)
	if h.RouteType != RouteFlood {
		t.Errorf("expected RouteFlood (1), got %d", h.RouteType)
	}
	if h.RouteTypeName != "FLOOD" {
		t.Errorf("expected FLOOD, got %s", h.RouteTypeName)
	}
}

func TestIsTransportRoute(t *testing.T) {
	if !isTransportRoute(RouteTransportFlood) {
		t.Error("expected RouteTransportFlood to be transport")
	}
	if !isTransportRoute(RouteTransportDirect) {
		t.Error("expected RouteTransportDirect to be transport")
	}
	if isTransportRoute(RouteFlood) {
		t.Error("expected RouteFlood to NOT be transport")
	}
	if isTransportRoute(RouteDirect) {
		t.Error("expected RouteDirect to NOT be transport")
	}
}

func TestDecodePacket_TransportFloodHasCodes(t *testing.T) {
	// Build a minimal TRANSPORT_FLOOD packet:
	// Header 0x14 (route=0/T_FLOOD, payload=5/GRP_TXT)
	// Transport codes: AABB CCDD (4 bytes)
	// Path byte: 0x00 (hashSize=1, hashCount=0)
	// Payload: at least some bytes for GRP_TXT
	hex := "14AABBCCDD00112233445566778899"
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if pkt.TransportCodes == nil {
		t.Fatal("expected transport codes to be present")
	}
	if pkt.TransportCodes.Code1 != "AABB" {
		t.Errorf("expected Code1=AABB, got %s", pkt.TransportCodes.Code1)
	}
	if pkt.TransportCodes.Code2 != "CCDD" {
		t.Errorf("expected Code2=CCDD, got %s", pkt.TransportCodes.Code2)
	}
}

func TestDecodePacket_FloodHasNoCodes(t *testing.T) {
	// Header 0x11 (route=1/FLOOD, payload=4/ADVERT)
	// Path byte: 0x00 (no hops)
	// Some payload bytes
	hex := "110011223344556677889900AABBCCDD"
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if pkt.TransportCodes != nil {
		t.Error("expected no transport codes for FLOOD route")
	}
}


func TestZeroHopDirectHashSize(t *testing.T) {
	// DIRECT (RouteType=2) + REQ (PayloadType=0) → header byte = 0x02
	// pathByte=0x00 → hash_count=0, hash_size bits=0 → should get HashSize=0
	// Need at least a few payload bytes after pathByte.
	hex := "02" + "00" + repeatHex("AA", 20)
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket failed: %v", err)
	}
	if pkt.Path.HashSize != 0 {
		t.Errorf("DIRECT zero-hop: want HashSize=0, got %d", pkt.Path.HashSize)
	}
}

func TestZeroHopDirectHashSizeWithNonZeroUpperBits(t *testing.T) {
	// DIRECT (RouteType=2) + REQ (PayloadType=0) → header byte = 0x02
	// pathByte=0x40 → hash_count=0, hash_size bits=01 → should still get HashSize=0
	// because hash_count is zero (lower 6 bits are 0).
	hex := "02" + "40" + repeatHex("AA", 20)
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket failed: %v", err)
	}
	if pkt.Path.HashSize != 0 {
		t.Errorf("DIRECT zero-hop with hash_size bits set: want HashSize=0, got %d", pkt.Path.HashSize)
	}
}

func TestZeroHopTransportDirectHashSize(t *testing.T) {
	// TRANSPORT_DIRECT (RouteType=3) + REQ (PayloadType=0) → header byte = 0x03
	// 4 bytes transport codes + pathByte=0x00 → hash_count=0 → should get HashSize=0
	hex := "03" + "11223344" + "00" + repeatHex("AA", 20)
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket failed: %v", err)
	}
	if pkt.Path.HashSize != 0 {
		t.Errorf("TRANSPORT_DIRECT zero-hop: want HashSize=0, got %d", pkt.Path.HashSize)
	}
}

func TestZeroHopTransportDirectHashSizeWithNonZeroUpperBits(t *testing.T) {
	// pathByte=0xC0 → hash_size bits=11 (4, reserved per firmware Packet.cpp:13-18).
	// Firmware Packet::isValidPathLen rejects this regardless of hash_count,
	// because hash_size==4 is reserved. Go decoder must mirror that — even
	// when hash_count==0, an attacker-emitted 0xC0 byte should not be
	// silently accepted; firmware never emits hash_size==4.
	hex := "03" + "11223344" + "C0" + repeatHex("AA", 20)
	_, err := DecodePacket(hex, false)
	if err == nil {
		t.Fatalf("DecodePacket(pathByte=0xC0) succeeded; want error mirroring firmware Packet.cpp:13-18 (hash_size==4 reserved)")
	}
}

func TestNonDirectZeroPathByteKeepsHashSize(t *testing.T) {
	// FLOOD (RouteType=1) + REQ (PayloadType=0) → header byte = 0x01
	// pathByte=0x00 → even though hash_count=0, non-DIRECT should keep HashSize=1
	hex := "01" + "00" + repeatHex("AA", 20)
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket failed: %v", err)
	}
	if pkt.Path.HashSize != 1 {
		t.Errorf("FLOOD zero pathByte: want HashSize=1 (unchanged), got %d", pkt.Path.HashSize)
	}
}

func TestDirectNonZeroHopKeepsHashSize(t *testing.T) {
	// DIRECT (RouteType=2) + REQ (PayloadType=0) → header byte = 0x02
	// pathByte=0x01 → hash_count=1, hash_size=1 → should keep HashSize=1
	// Need 1 hop hash byte after pathByte.
	hex := "02" + "01" + repeatHex("BB", 21)
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket failed: %v", err)
	}
	if pkt.Path.HashSize != 1 {
		t.Errorf("DIRECT with 1 hop: want HashSize=1, got %d", pkt.Path.HashSize)
	}
}

func repeatHex(byteHex string, n int) string {
	s := ""
	for i := 0; i < n; i++ {
		s += byteHex
	}
	return s
}

func TestDecodePacket_TraceHopsCompleted(t *testing.T) {
	// Build a TRACE packet:
	// header: route=FLOOD(1), payload=TRACE(9), version=0 → (0<<6)|(9<<2)|1 = 0x25
	// path_length: hash_size bits=0b00 (1-byte), hash_count=2 (2 SNR bytes) → 0x02
	// path: 2 SNR bytes: 0xAA, 0xBB
	// payload: tag(4 LE) + authCode(4 LE) + flags(1) + 4 hop hashes (1 byte each)
	hex := "2502AABB" + // header + path_length + 2 SNR bytes
		"01000000" + // tag = 1
		"02000000" + // authCode = 2
		"00" + // flags = 0
		"DEADBEEF" // 4 hops (1-byte hash each)

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if pkt.Payload.Type != "TRACE" {
		t.Fatalf("expected TRACE, got %s", pkt.Payload.Type)
	}
	// Full intended route = 4 hops from payload
	if len(pkt.Path.Hops) != 4 {
		t.Errorf("expected 4 hops, got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
	}
	// HopsCompleted = 2 (from header path SNR count)
	if pkt.Path.HopsCompleted == nil {
		t.Fatal("expected HopsCompleted to be set")
	}
	if *pkt.Path.HopsCompleted != 2 {
		t.Errorf("expected HopsCompleted=2, got %d", *pkt.Path.HopsCompleted)
	}
	// FLOOD routing for TRACE is anomalous
	if pkt.Anomaly == "" {
		t.Error("expected anomaly flag for FLOOD-routed TRACE")
	}
}

func TestDecodePacket_TraceNoSNR(t *testing.T) {
	// TRACE with 0 SNR bytes (trace hasn't been forwarded yet)
	// path_length: hash_size=0b00 (1-byte), hash_count=0 → 0x00
	hex := "2500" + // header + path_length (0 hops in header)
		"01000000" + // tag
		"02000000" + // authCode
		"00" + // flags
		"AABBCC" // 3 hops intended

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if pkt.Path.HopsCompleted == nil {
		t.Fatal("expected HopsCompleted to be set")
	}
	if *pkt.Path.HopsCompleted != 0 {
		t.Errorf("expected HopsCompleted=0, got %d", *pkt.Path.HopsCompleted)
	}
	if len(pkt.Path.Hops) != 3 {
		t.Errorf("expected 3 hops, got %d", len(pkt.Path.Hops))
	}
}

func TestDecodePacket_TraceFullyCompleted(t *testing.T) {
	// TRACE where all hops completed (SNR count = hop count)
	// path_length: hash_size=0b00 (1-byte), hash_count=3 → 0x03
	hex := "2503AABBCC" + // header + path_length + 3 SNR bytes
		"01000000" + // tag
		"02000000" + // authCode
		"00" + // flags
		"DDEEFF" // 3 hops intended

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if pkt.Path.HopsCompleted == nil {
		t.Fatal("expected HopsCompleted to be set")
	}
	if *pkt.Path.HopsCompleted != 3 {
		t.Errorf("expected HopsCompleted=3, got %d", *pkt.Path.HopsCompleted)
	}
	if len(pkt.Path.Hops) != 3 {
		t.Errorf("expected 3 hops, got %d", len(pkt.Path.Hops))
	}
}

func TestDecodePacket_TraceFlags1_TwoBytePathSz(t *testing.T) {
	// TRACE with flags=1 → path_sz = 1 << (1 & 0x03) = 2-byte hashes
	// Firmware always sends TRACE as DIRECT (route_type=2), so header byte =
	// (0<<6)|(9<<2)|2 = 0x26. path_length 0x00 = 0 SNR bytes.
	hex := "2600" + // header (DIRECT+TRACE) + path_length (0 SNR)
		"01000000" + // tag
		"02000000" + // authCode
		"01" + // flags = 1 → path_sz = 2
		"AABBCCDD" // 4 bytes = 2 hops of 2-byte each

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if len(pkt.Path.Hops) != 2 {
		t.Errorf("expected 2 hops (2-byte path_sz), got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
	}
	if pkt.Path.HashSize != 2 {
		t.Errorf("expected HashSize=2, got %d", pkt.Path.HashSize)
	}
	if pkt.Anomaly != "" {
		t.Errorf("expected no anomaly for DIRECT TRACE, got %q", pkt.Anomaly)
	}
}

func TestDecodePacket_TraceFlags2_FourBytePathSz(t *testing.T) {
	// TRACE with flags=2 → path_sz = 1 << (2 & 0x03) = 4-byte hashes
	// DIRECT route_type (0x26)
	hex := "2600" + // header (DIRECT+TRACE) + path_length (0 SNR)
		"01000000" + // tag
		"02000000" + // authCode
		"02" + // flags = 2 → path_sz = 4
		"AABBCCDD11223344" // 8 bytes = 2 hops of 4-byte each

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if len(pkt.Path.Hops) != 2 {
		t.Errorf("expected 2 hops (4-byte path_sz), got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
	}
	if pkt.Path.HashSize != 4 {
		t.Errorf("expected HashSize=4, got %d", pkt.Path.HashSize)
	}
}

func TestDecodePacket_TracePathSzUnevenPayload(t *testing.T) {
	// TRACE with flags=1 → path_sz=2, but 5 bytes of path data (not evenly divisible)
	// Should produce 2 hops (4 bytes) and ignore the trailing byte
	hex := "2600" + // header (DIRECT+TRACE) + path_length (0 SNR)
		"01000000" + // tag
		"02000000" + // authCode
		"01" + // flags = 1 → path_sz = 2
		"AABBCCDDEE" // 5 bytes → 2 hops, 1 byte remainder ignored

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if len(pkt.Path.Hops) != 2 {
		t.Errorf("expected 2 hops (trailing byte ignored), got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
	}
}

func TestDecodePacket_TraceTransportDirect(t *testing.T) {
	// TRACE via TRANSPORT_DIRECT (route_type=3) — includes 4 transport code bytes
	// header: (0<<6)|(9<<2)|3 = 0x27
	hex := "27" + // header (TRANSPORT_DIRECT+TRACE)
		"AABB" + "CCDD" + // transport codes (2+2 bytes)
		"02" + // path_length: hash_count=2 SNR bytes
		"EEFF" + // 2 SNR bytes
		"01000000" + // tag
		"02000000" + // authCode
		"00" + // flags = 0 → path_sz = 1
		"112233" // 3 hops (1-byte each)

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if pkt.TransportCodes == nil {
		t.Fatal("expected transport codes for TRANSPORT_DIRECT")
	}
	if pkt.TransportCodes.Code1 != "AABB" {
		t.Errorf("expected Code1=AABB, got %s", pkt.TransportCodes.Code1)
	}
	if len(pkt.Path.Hops) != 3 {
		t.Errorf("expected 3 hops, got %d: %v", len(pkt.Path.Hops), pkt.Path.Hops)
	}
	if pkt.Path.HopsCompleted == nil || *pkt.Path.HopsCompleted != 2 {
		t.Errorf("expected HopsCompleted=2, got %v", pkt.Path.HopsCompleted)
	}
	if pkt.Anomaly != "" {
		t.Errorf("expected no anomaly for TRANSPORT_DIRECT TRACE, got %q", pkt.Anomaly)
	}
}

func TestDecodePacket_TraceFloodRouteAnomaly(t *testing.T) {
	// TRACE via FLOOD (route_type=1) — anomalous per firmware (firmware only
	// sends TRACE as DIRECT). Should still parse but flag the anomaly.
	hex := "2500" + // header (FLOOD+TRACE) + path_length (0 SNR)
		"01000000" + // tag
		"02000000" + // authCode
		"01" + // flags = 1 → path_sz = 2
		"AABBCCDD" // 4 bytes = 2 hops of 2-byte each

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("should not crash on anomalous FLOOD+TRACE: %v", err)
	}
	if len(pkt.Path.Hops) != 2 {
		t.Errorf("expected 2 hops even for anomalous FLOOD route, got %d", len(pkt.Path.Hops))
	}
	if pkt.Anomaly == "" {
		t.Error("expected anomaly flag for FLOOD-routed TRACE, got empty string")
	}
}

func TestDecodeAdvertSignatureValidation(t *testing.T) {
	pub, priv, err := ed25519.GenerateKey(nil)
	if err != nil {
		t.Fatal(err)
	}

	var timestamp uint32 = 1234567890
	appdata := []byte{0x02} // flags: repeater, no extras

	// Build signed message: pubKey(32) + timestamp(4 LE) + appdata
	msg := make([]byte, 32+4+len(appdata))
	copy(msg[0:32], pub)
	binary.LittleEndian.PutUint32(msg[32:36], timestamp)
	copy(msg[36:], appdata)
	sig := ed25519.Sign(priv, msg)

	// Build a raw advert buffer: pubKey(32) + timestamp(4) + signature(64) + appdata
	buf := make([]byte, 100+len(appdata))
	copy(buf[0:32], pub)
	binary.LittleEndian.PutUint32(buf[32:36], timestamp)
	copy(buf[36:100], sig)
	copy(buf[100:], appdata)

	// With validation enabled
	p := decodeAdvert(buf, true)
	if p.SignatureValid == nil {
		t.Fatal("expected SignatureValid to be set")
	}
	if !*p.SignatureValid {
		t.Error("expected valid signature")
	}
	if p.PubKey != hex.EncodeToString(pub) {
		t.Errorf("pubkey mismatch: got %s", p.PubKey)
	}

	// Tamper with signature → invalid
	buf[40] ^= 0xFF
	p = decodeAdvert(buf, true)
	if p.SignatureValid == nil {
		t.Fatal("expected SignatureValid to be set")
	}
	if *p.SignatureValid {
		t.Error("expected invalid signature after tampering")
	}

	// Without validation → SignatureValid should be nil
	p = decodeAdvert(buf, false)
	if p.SignatureValid != nil {
		t.Error("expected SignatureValid to be nil when validation disabled")
	}
}

func TestDecodePacket_TraceSNRValues(t *testing.T) {
	// TRACE packet with 3 SNR bytes in header path:
	// SNR byte 0: 0x14 = int8(20) → 20/4.0 = 5.0 dB
	// SNR byte 1: 0xF4 = int8(-12) → -12/4.0 = -3.0 dB
	// SNR byte 2: 0x08 = int8(8) → 8/4.0 = 2.0 dB
	// header: DIRECT+TRACE = (0<<6)|(9<<2)|2 = 0x26
	// path_length: hash_size=0b00 (1-byte), hash_count=3 → 0x03
	hex := "2603" + "14F408" + // header + path_byte + 3 SNR bytes
		"01000000" + // tag
		"02000000" + // authCode
		"00" + // flags=0 → path_sz=1
		"AABBCCDD" // 4 route hops (1-byte each)

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if pkt.Payload.SNRValues == nil {
		t.Fatal("expected SNRValues to be populated")
	}
	if len(pkt.Payload.SNRValues) != 3 {
		t.Fatalf("expected 3 SNR values, got %d", len(pkt.Payload.SNRValues))
	}
	expected := []float64{5.0, -3.0, 2.0}
	for i, want := range expected {
		if pkt.Payload.SNRValues[i] != want {
			t.Errorf("SNRValues[%d] = %v, want %v", i, pkt.Payload.SNRValues[i], want)
		}
	}
}

func TestDecodePacket_TraceNoSNRValues(t *testing.T) {
	// TRACE with 0 SNR bytes → SNRValues should be nil/empty
	hex := "2600" + // header + path_byte (0 hops)
		"01000000" + // tag
		"02000000" + // authCode
		"00" + // flags
		"AABB" // 2 route hops

	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket error: %v", err)
	}
	if len(pkt.Payload.SNRValues) != 0 {
		t.Errorf("expected empty SNRValues, got %v", pkt.Payload.SNRValues)
	}
}

// TestDecodePacketBoundsFromWire_Issue1211 — mirror of ingestor test.
// Malformed pathByte=0xF6 inside a 15-byte buffer triggered
// `slice bounds out of range [218:15]`.
func TestDecodePacketBoundsFromWire_Issue1211(t *testing.T) {
	raw := "12F6"
	for i := 0; i < 13; i++ {
		raw += "AA"
	}
	defer func() {
		if r := recover(); r != nil {
			t.Fatalf("DecodePacket panicked on malformed input: %v", r)
		}
	}()
	pkt, err := DecodePacket(raw, false)
	if err == nil {
		t.Fatalf("expected error for malformed packet, got nil; pkt=%+v", pkt)
	}
}

// Adv M2: see cmd/ingestor/decoder_test.go — sweep gated on !testing.Short();
// FuzzDecodePacketTruncated below is the real fuzzing target.
func TestDecodePacketFuzzTruncated_Issue1211(t *testing.T) {
	defer func() {
		if r := recover(); r != nil {
			t.Fatalf("DecodePacket panicked during fuzz: %v", r)
		}
	}()
	if testing.Short() {
		t.Skip("skipping exhaustive sweep in -short mode; use FuzzDecodePacketTruncated")
	}
	for hdr := 0; hdr < 256; hdr++ {
		for pb := 0; pb < 256; pb++ {
			for tail := 0; tail < 20; tail++ {
				raw := hex.EncodeToString([]byte{byte(hdr), byte(pb)})
				for i := 0; i < tail; i++ {
					raw += "00"
				}
				_, _ = DecodePacket(raw, false)
			}
		}
	}
}

// FuzzDecodePacketTruncated — native go fuzz target. Zero panics required.
// Run with: go test -fuzz=FuzzDecodePacketTruncated -fuzztime=30s ./cmd/server
func FuzzDecodePacketTruncated(f *testing.F) {
	seeds := [][]byte{
		{0x12, 0xF6, 0xAA, 0xAA, 0xAA},
		{0x12, 0x00},
		{0x03, 0x11, 0x22, 0x33, 0x44, 0xC0, 0xAA, 0xAA, 0xAA},
	}
	for _, s := range seeds {
		f.Add(s)
	}
	f.Fuzz(func(t *testing.T, data []byte) {
		defer func() {
			if r := recover(); r != nil {
				t.Fatalf("DecodePacket panicked on input %x: %v", data, r)
			}
		}()
		_, _ = DecodePacket(hex.EncodeToString(data), false)
	})
}

// TestDecodeAdvertOversizedNameTruncated asserts decodeAdvert truncates the
// advert name to firmware's MAX_ADVERT_DATA_SIZE=32 (firmware/src/MeshCore.h:11).
// Firmware writes the node name into a 32-byte buffer, so any on-wire advert
// carrying >32 bytes of name data is adversarial — the Go decoder must not
// surface attacker-controlled bytes beyond what firmware would ever emit.
func TestDecodeAdvertOversizedNameTruncated(t *testing.T) {
	pubkey := repeatHex("AA", 32)
	timestamp := "78563412"
	signature := repeatHex("BB", 64)
	flags := "81" // chat(1) | hasName(0x80), no location, no feat1/2
	// 64-byte ASCII 'X' name (firmware buffer is only 32 bytes).
	name := repeatHex("58", 64)
	hex := "1200" + pubkey + timestamp + signature + flags + name
	pkt, err := DecodePacket(hex, false)
	if err != nil {
		t.Fatalf("DecodePacket: %v", err)
	}
	if got := len(pkt.Payload.Name); got > 32 {
		t.Errorf("name length=%d, want <=32 (MAX_ADVERT_DATA_SIZE firmware/src/MeshCore.h:11)", got)
	}
}