From 56c04f1fecfd61472b75873d017d97e65cc78325 Mon Sep 17 00:00:00 2001
From: Tom Thorogood <me+github@tomthorogood.co.uk>
Date: Tue, 30 Apr 2019 17:44:07 +0930
Subject: [PATCH] Fix dns:"hex" field len being off-by-one (#959)

dns:"hex" fields are not packed with any extra trailing byte. This was
causing a mismatch between PackRR and Len.
---
 types_generate.go |  4 +---
 ztypes.go         | 16 ++++++++--------
 2 files changed, 9 insertions(+), 11 deletions(-)

diff --git a/types_generate.go b/types_generate.go
index cbb4a00c..8cda2a74 100644
--- a/types_generate.go
+++ b/types_generate.go
@@ -189,10 +189,8 @@ func main() {
 				o("l += base64.StdEncoding.DecodedLen(len(rr.%s))\n")
 			case strings.HasPrefix(st.Tag(i), `dns:"size-hex:`): // this has an extra field where the length is stored
 				o("l += len(rr.%s)/2\n")
-			case strings.HasPrefix(st.Tag(i), `dns:"size-hex`):
-				fallthrough
 			case st.Tag(i) == `dns:"hex"`:
-				o("l += len(rr.%s)/2 + 1\n")
+				o("l += len(rr.%s)/2\n")
 			case st.Tag(i) == `dns:"any"`:
 				o("l += len(rr.%s)\n")
 			case st.Tag(i) == `dns:"a"`:
diff --git a/ztypes.go b/ztypes.go
index 495a83e3..f7ec8352 100644
--- a/ztypes.go
+++ b/ztypes.go
@@ -312,12 +312,12 @@ func (rr *DS) len(off int, compression map[string]struct{}) int {
 	l += 2 // KeyTag
 	l++    // Algorithm
 	l++    // DigestType
-	l += len(rr.Digest)/2 + 1
+	l += len(rr.Digest) / 2
 	return l
 }
 func (rr *EID) len(off int, compression map[string]struct{}) int {
 	l := rr.Hdr.len(off, compression)
-	l += len(rr.Endpoint)/2 + 1
+	l += len(rr.Endpoint) / 2
 	return l
 }
 func (rr *EUI48) len(off int, compression map[string]struct{}) int {
@@ -452,7 +452,7 @@ func (rr *NID) len(off int, compression map[string]struct{}) int {
 }
 func (rr *NIMLOC) len(off int, compression map[string]struct{}) int {
 	l := rr.Hdr.len(off, compression)
-	l += len(rr.Locator)/2 + 1
+	l += len(rr.Locator) / 2
 	return l
 }
 func (rr *NINFO) len(off int, compression map[string]struct{}) int {
@@ -505,7 +505,7 @@ func (rr *PX) len(off int, compression map[string]struct{}) int {
 }
 func (rr *RFC3597) len(off int, compression map[string]struct{}) int {
 	l := rr.Hdr.len(off, compression)
-	l += len(rr.Rdata)/2 + 1
+	l += len(rr.Rdata) / 2
 	return l
 }
 func (rr *RKEY) len(off int, compression map[string]struct{}) int {
@@ -546,7 +546,7 @@ func (rr *SMIMEA) len(off int, compression map[string]struct{}) int {
 	l++ // Usage
 	l++ // Selector
 	l++ // MatchingType
-	l += len(rr.Certificate)/2 + 1
+	l += len(rr.Certificate) / 2
 	return l
 }
 func (rr *SOA) len(off int, compression map[string]struct{}) int {
@@ -579,7 +579,7 @@ func (rr *SSHFP) len(off int, compression map[string]struct{}) int {
 	l := rr.Hdr.len(off, compression)
 	l++ // Algorithm
 	l++ // Type
-	l += len(rr.FingerPrint)/2 + 1
+	l += len(rr.FingerPrint) / 2
 	return l
 }
 func (rr *TA) len(off int, compression map[string]struct{}) int {
@@ -587,7 +587,7 @@ func (rr *TA) len(off int, compression map[string]struct{}) int {
 	l += 2 // KeyTag
 	l++    // Algorithm
 	l++    // DigestType
-	l += len(rr.Digest)/2 + 1
+	l += len(rr.Digest) / 2
 	return l
 }
 func (rr *TALINK) len(off int, compression map[string]struct{}) int {
@@ -614,7 +614,7 @@ func (rr *TLSA) len(off int, compression map[string]struct{}) int {
 	l++ // Usage
 	l++ // Selector
 	l++ // MatchingType
-	l += len(rr.Certificate)/2 + 1
+	l += len(rr.Certificate) / 2
 	return l
 }
 func (rr *TSIG) len(off int, compression map[string]struct{}) int {