From cef5150e0252058fe1af95558e9b9f5153443b11 Mon Sep 17 00:00:00 2001
From: Matthijs Mekking <github@pletterpet.nl>
Date: Mon, 18 Dec 2017 21:15:56 +0100
Subject: [PATCH] Fix issue #605 (#606)

This makes `client.Readmsg` always return the message,
regardless if and how unpacking the message failed.
---
 client.go | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/client.go b/client.go
index 2c515885..856b1698 100644
--- a/client.go
+++ b/client.go
@@ -192,8 +192,10 @@ func (c *Client) exchange(m *Msg, a string) (r *Msg, rtt time.Duration, err erro
 }
 
 // ReadMsg reads a message from the connection co.
-// If the received message contains a TSIG record the transaction
-// signature is verified.
+// If the received message contains a TSIG record the transaction signature
+// is verified. This method always tries to return the message, however if an
+// error is returned there are no guarantees that the returned message is a
+// valid representation of the packet read.
 func (co *Conn) ReadMsg() (*Msg, error) {
 	p, err := co.ReadMsgHeader(nil)
 	if err != nil {
@@ -202,13 +204,10 @@ func (co *Conn) ReadMsg() (*Msg, error) {
 
 	m := new(Msg)
 	if err := m.Unpack(p); err != nil {
-		// If ErrTruncated was returned, we still want to allow the user to use
+		// If an error was returned, we still want to allow the user to use
 		// the message, but naively they can just check err if they don't want
-		// to use a truncated message
-		if err == ErrTruncated {
-			return m, err
-		}
-		return nil, err
+		// to use an erroneous message
+		return m, err
 	}
 	if t := m.IsTsig(); t != nil {
 		if _, ok := co.TsigSecret[t.Hdr.Name]; !ok {