From 43bb76480821e6be4d85fe19bbb63cd0b6c06906 Mon Sep 17 00:00:00 2001
From: Peter Wilson <peter.wilson@hashicorp.com>
Date: Fri, 29 Apr 2022 14:57:17 +0100
Subject: [PATCH] Do sockaddr template parsing only when needed (#15224)

---
 changelog/15224.txt                        |  3 ++
 internalshared/configutil/listener.go      |  8 ++++
 internalshared/configutil/listener_test.go | 49 ++++++++++++++++++++++
 sdk/go.sum                                 |  1 -
 4 files changed, 60 insertions(+), 1 deletion(-)
 create mode 100644 changelog/15224.txt
 create mode 100644 internalshared/configutil/listener_test.go

diff --git a/changelog/15224.txt b/changelog/15224.txt
new file mode 100644
index 000000000..c25ccf630
--- /dev/null
+++ b/changelog/15224.txt
@@ -0,0 +1,3 @@
+```release-note:bug
+core/config: Only ask the system about network interfaces when address configs contain a template having the format: {{ ... }}
+```
\ No newline at end of file
diff --git a/internalshared/configutil/listener.go b/internalshared/configutil/listener.go
index 0df97bdf0..a9e1d7b5c 100644
--- a/internalshared/configutil/listener.go
+++ b/internalshared/configutil/listener.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"fmt"
 	"net/textproto"
+	"regexp"
 	"strings"
 	"time"
 
@@ -410,7 +411,14 @@ func ParseListeners(result *SharedConfig, list *ast.ObjectList) error {
 
 // ParseSingleIPTemplate is used as a helper function to parse out a single IP
 // address from a config parameter.
+// If the input doesn't appear to contain the 'template' format,
+// it will return the specified input unchanged.
 func ParseSingleIPTemplate(ipTmpl string) (string, error) {
+	r := regexp.MustCompile("{{.*?}}")
+	if !r.MatchString(ipTmpl) {
+		return ipTmpl, nil
+	}
+
 	out, err := template.Parse(ipTmpl)
 	if err != nil {
 		return "", fmt.Errorf("unable to parse address template %q: %v", ipTmpl, err)
diff --git a/internalshared/configutil/listener_test.go b/internalshared/configutil/listener_test.go
new file mode 100644
index 000000000..803086e48
--- /dev/null
+++ b/internalshared/configutil/listener_test.go
@@ -0,0 +1,49 @@
+package configutil
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestParseSingleIPTemplate(t *testing.T) {
+	type args struct {
+		ipTmpl string
+	}
+	tests := []struct {
+		name    string
+		arg     string
+		want    string
+		wantErr assert.ErrorAssertionFunc
+	}{
+		{
+			name:    "test https addr",
+			arg:     "https://vaultproject.io:8200",
+			want:    "https://vaultproject.io:8200",
+			wantErr: assert.NoError,
+		},
+		{
+			name:    "test invalid template func",
+			arg:     "{{FooBar}}",
+			want:    "",
+			wantErr: assert.Error,
+		},
+		{
+			name:    "test partial template",
+			arg:     "{{FooBar",
+			want:    "{{FooBar",
+			wantErr: assert.NoError,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := ParseSingleIPTemplate(tt.arg)
+			if !tt.wantErr(t, err, fmt.Sprintf("ParseSingleIPTemplate(%v)", tt.arg)) {
+				return
+			}
+
+			assert.Equalf(t, tt.want, got, "ParseSingleIPTemplate(%v)", tt.arg)
+		})
+	}
+}
diff --git a/sdk/go.sum b/sdk/go.sum
index 957410de7..59bf6d3dd 100644
--- a/sdk/go.sum
+++ b/sdk/go.sum
@@ -107,7 +107,6 @@ github.com/hashicorp/go-secure-stdlib/base62 v0.1.1 h1:6KMBnfEv0/kLAz0O76sliN5mX
 github.com/hashicorp/go-secure-stdlib/base62 v0.1.1/go.mod h1:EdWO6czbmthiwZ3/PUsDV+UD1D5IRU4ActiaWGwt0Yw=
 github.com/hashicorp/go-secure-stdlib/mlock v0.1.1 h1:cCRo8gK7oq6A2L6LICkUZ+/a5rLiRXFMf1Qd4xSwxTc=
 github.com/hashicorp/go-secure-stdlib/mlock v0.1.1/go.mod h1:zq93CJChV6L9QTfGKtfBxKqD7BqqXx5O04A/ns2p5+I=
-github.com/hashicorp/go-secure-stdlib/parseutil v0.1.1 h1:78ki3QBevHwYrVxnyVeaEz+7WtifHhauYF23es/0KlI=
 github.com/hashicorp/go-secure-stdlib/parseutil v0.1.1/go.mod h1:QmrqtbKuxxSWTN3ETMPuB+VtEiBJ/A9XhoYGv8E1uD8=
 github.com/hashicorp/go-secure-stdlib/parseutil v0.1.4 h1:hrIH/qrOTHfG9a1Jz6Z2jQf7Xe77AaD464W1fCFLwPQ=
 github.com/hashicorp/go-secure-stdlib/parseutil v0.1.4/go.mod h1:QmrqtbKuxxSWTN3ETMPuB+VtEiBJ/A9XhoYGv8E1uD8=