minor tweaks for multi-line nsupdate

internal/config/struct-config.go

@@ -32,10 +32,12 @@ type Config struct {
 	RefreshSeconds int    `default:"14400"                                                                                                        env:"refresh_seconds"`
 
 	// nsupdate
-	NSUKey    string `env:"nsupdate-key"        secret:"true"`
-	NSUPort   int    `default:"53"              env:"nsupdate-port"`
-	NSUServer string `default:"ns1.example.com" env:"nsupdate-server"`
-	NSUZone   string `default:"example.com"     env:"nsupdate-zone"`
+	NSUKeyLabel     string `env:"nsupdate-key-label"`
+	NSUKey          string `env:"nsupdate-key"        secret:"true"`
+	NSUKeyAlgorithm string `default:"hmac-sha512"     env:"nsupdate-key-algorithm"`
+	NSUPort         int    `default:"53"              env:"nsupdate-port"`
+	NSUServer       string `default:"ns1.example.com" env:"nsupdate-server"`
+	NSUZone         string `default:"example.com"     env:"nsupdate-zone"`
 }
 
 // New initializes the config variable for use with a prepared set of defaults.

internal/nsupdate/nsupdate.go

@@ -13,15 +13,49 @@ import (
 	"istheinternetonfire.app/internal/config"
 )
 
-func New() NsUpdateStruct {
-	return NsUpdateStruct{}
+func New(keyLabel, keyAlgorithm, keySecret, server string, port int, zone string) NsUpdateStruct {
+	return NsUpdateStruct{
+		Key: KeyStruct{
+			Label:     keyLabel,
+			Algorithm: keyAlgorithm,
+			Secret:    keySecret,
+		},
+		Server: server,
+		Port:   port,
+		Zone:   zone,
+	}
 }
 
+var (
+	// escape characters
+	specialChars = []string{
+		`"`,
+	}
+)
+
 func (c NsUpdateStruct) Update(record, recordType, value string) error {
+	if strings.ToUpper(recordType) == "TXT" {
+		// sanitize TXT value
+		for _, v := range specialChars {
+			value = strings.ReplaceAll(value, v, fmt.Sprintf("\\%s", v))
+		}
+		// convert to rune
+		a := []rune(value)
+		// split into 255 character blocks
+		value = ""
+		for i, r := range a {
+			value += string(r)
+			if i > 0 && (i+1)%254 == 0 {
+				value += string(`" "`)
+			}
+		}
+		// convert new lines into safe string
+		value = strings.ReplaceAll(value, "\n", "%n")
+	}
+
 	r, err := getRecord(c.Server, c.Port, recordType, record)
 	if err != nil {
-		config.Cfg.Log.Debug("creating record", "record", record)
-		return c.Create(record, recordType, value)
+		config.Cfg.Log.Info("unable to get existing record", "record", record, "error", err)
 	}
 
 	if r != value {
@@ -48,7 +82,7 @@ func (c NsUpdateStruct) Delete(record, recordType string) error {
 
 	command := fmt.Sprintf(`#/bin/env/sh
 read -r -d '' DDNS_KEY <<- EOF
-key "update" {
+key "%s" {
 	algorithm "%s";
 	secret "%s";
 };
@@ -60,7 +94,7 @@ send
 EOF
 
 nsupdate -v -k <(printf '%%s' "${DDNS_KEY}") <(printf '%%s\n\n' "${COMMAND}")
-`, c.Key.Algorithm, c.Key.Secret, c.Server, record, strings.ToUpper(recordType))
+`, c.Key.Label, c.Key.Algorithm, c.Key.Secret, c.Server, record, strings.ToUpper(recordType))
 	cmd := exec.Command("/usr/bin/sh", "-c", command)
 	cmd.Stdout = &stdout
 	cmd.Stderr = &stderr
@@ -80,19 +114,19 @@ func (c NsUpdateStruct) Create(record, recordType, value string) error {
 
 	command := fmt.Sprintf(`#/bin/env/sh
 read -r -d '' DDNS_KEY <<- EOF
-key "update" {
+key "%s" {
 	algorithm "%s";
 	secret "%s";
 };
 EOF
 read -r -d '' COMMAND <<- EOF
 server %s
-update add %s. 30 IN %s %s
+update add %s. 30 IN %s "%s"
 send
 EOF
 
 nsupdate -v -k <(printf '%%s' "${DDNS_KEY}") <(printf '%%s\n\n' "${COMMAND}")
-`, c.Key.Algorithm, c.Key.Secret, c.Server, record, strings.ToUpper(recordType), value)
+`, c.Key.Label, c.Key.Algorithm, c.Key.Secret, c.Server, record, strings.ToUpper(recordType), value)
 	cmd := exec.Command("/usr/bin/sh", "-c", command)
 	cmd.Stdout = &stdout
 	cmd.Stderr = &stderr

internal/nsupdate/struct-nsupdate.go

@@ -1,13 +1,14 @@
 package nsupdate
 
 type NsUpdateStruct struct {
-	Key    KeyStruct `json:"key" yaml:"key"`
+	Key    KeyStruct `json:"key"    yaml:"key"`
 	Server string    `json:"server" yaml:"server"`
 	Port   int       `json:"port"   yaml:"port"`
 	Zone   string    `json:"zone"   yaml:"zone"`
 }
 
 type KeyStruct struct {
+	Label     string `json:"key-label" yaml:"key-label"`
 	Algorithm string `json:"algorithm" yaml:"algorithm"`
-	Secret    string `json:"Secret"    yaml:"secret"`
+	Secret    string `json:"secret"    yaml:"secret"`
 }