From ea340372b8dbecceb2dcca21f9305d357ff346bc Mon Sep 17 00:00:00 2001
From: mzz2017 <2017@duck.com>
Date: Tue, 21 Feb 2023 16:28:09 +0800
Subject: [PATCH] fix: No AddrPort presented for LAN

---
 control/control_plane.go |  3 ++-
 control/kern/tproxy.c    | 10 ++++------
 control/utils.go         |  8 +++++---
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/control/control_plane.go b/control/control_plane.go
index f6aff95..313f8ff 100644
--- a/control/control_plane.go
+++ b/control/control_plane.go
@@ -533,9 +533,10 @@ func (c *ControlPlane) ListenAndServe(port uint16) (err error) {
 				routingResult, err := c.core.RetrieveRoutingResult(src, pktDst, unix.IPPROTO_UDP)
 				if err != nil {
 					// WAN. Old method.
+					lastErr := err
 					addrHdr, dataOffset, err := ParseAddrHdr(data)
 					if err != nil {
-						c.log.Warnf("No AddrPort presented: %v", err)
+						c.log.Warnf("No AddrPort presented: %v, %v", lastErr, err)
 						return
 					}
 					copy(data, data[dataOffset:])
diff --git a/control/kern/tproxy.c b/control/kern/tproxy.c
index bae3936..8b2c75f 100644
--- a/control/kern/tproxy.c
+++ b/control/kern/tproxy.c
@@ -158,7 +158,7 @@ struct {
                           // side does not care it (full-cone).
   __type(value, struct dst_routing_result); // Original target.
   __uint(max_entries, MAX_DST_MAPPING_NUM);
-  /// NOTICE: It MUST be pinned.
+  /// NOTICE: It MUST be pinned, or connection may break.
   __uint(pinning, LIBBPF_PIN_BY_NAME);
 } tcp_dst_map
     SEC(".maps"); // This map is only for old method (redirect mode in WAN).
@@ -187,7 +187,6 @@ struct {
   __type(key, __u32);
   __type(value, struct lpm_key);
   __uint(max_entries, 3);
-  __uint(pinning, LIBBPF_PIN_BY_NAME);
 } lpm_key_map SEC(".maps");
 
 // h_sport, h_dport:
@@ -196,7 +195,6 @@ struct {
   __type(key, __u32);
   __type(value, __u16);
   __uint(max_entries, 2);
-  __uint(pinning, LIBBPF_PIN_BY_NAME);
 } h_port_map SEC(".maps");
 
 // l4proto, ipversion:
@@ -205,7 +203,6 @@ struct {
   __type(key, __u32);
   __type(value, __u32);
   __uint(max_entries, 2);
-  __uint(pinning, LIBBPF_PIN_BY_NAME);
 } l4proto_ipversion_map SEC(".maps");
 
 // IPPROTO to hdr_size
@@ -1763,8 +1760,9 @@ int tproxy_wan_egress(struct __sk_buff *skb) {
 
       if ((new_hdr.routing_result.outbound == OUTBOUND_DIRECT ||
            new_hdr.routing_result.outbound == OUTBOUND_MUST_DIRECT) &&
-          new_hdr.routing_result.mark == 0 // If mark is not zero, we should re-route it, so we
-                            // send it to control plane in WAN.
+          new_hdr.routing_result.mark ==
+              0 // If mark is not zero, we should re-route it, so we
+                // send it to control plane in WAN.
       ) {
         return TC_ACT_OK;
       } else if (unlikely(new_hdr.routing_result.outbound == OUTBOUND_BLOCK)) {
diff --git a/control/utils.go b/control/utils.go
index 5755d4e..6ea0a71 100644
--- a/control/utils.go
+++ b/control/utils.go
@@ -32,7 +32,7 @@ func (c *ControlPlaneCore) RetrieveRoutingResult(src, dst netip.AddrPort, l4prot
 	}
 
 	var routingResult bpfRoutingResult
-	if err := c.bpf.RoutingTuplesMap.LookupAndDelete(tuples, &routingResult); err != nil {
+	if err := c.bpf.RoutingTuplesMap.Lookup(tuples, &routingResult); err != nil {
 		return nil, fmt.Errorf("reading map: key [%v, %v, %v]: %w", src.String(), l4proto, dst.String(), err)
 	}
 	return &routingResult, nil
@@ -97,10 +97,12 @@ func ProcessName2String(pname []uint8) string {
 func Mac2String(mac []uint8) string {
 	ori := []byte(hex.EncodeToString(mac))
 	// Insert ":".
-	b := make([]byte, len(ori)/2*3)
+	b := make([]byte, len(ori)/2*3-1)
 	for i, j := 0, 0; i < len(ori); i, j = i+2, j+3 {
 		copy(b[j:j+2], ori[i:i+2])
-		b[j+2] = ':'
+		if j+2 < len(b) {
+			b[j+2] = ':'
+		}
 	}
 	return string(b)
 }