chore: convert GSM7 characters in TagMessageBox data

damonto · May 29, 2024 · 7ebba19 · 7ebba19
1 parent 7808dd9
commit 7ebba19
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Showing 4 changed files with 46 additions and 3 deletions.
diff --git a/internal/cloud/conn.go b/internal/cloud/conn.go
@@ -72,6 +72,11 @@ func (c *Conn) Handle(tag Tag, data []byte) {
 func (c *Conn) Send(tag Tag, data []byte) error {
 	c.lock.Lock()
 	defer c.lock.Unlock()
+
+	if tag == TagMessageBox {
+		data = ToGSM7(data)
+	}
+
 	packet := c.pack(tag, data)
 	if tag == TagAPDU {
 		slog.Debug("sending data to", "id", c.Id, "tag", tag, "packet", hex.EncodeToString(packet))

diff --git a/internal/cloud/download.go b/internal/cloud/download.go
@@ -24,7 +24,6 @@ const (
 var (
 	GSMNumberSign = []byte{0x23} // #
 	GSMDollarSign = []byte{0x02} // $
-	GSMUnderscore = []byte{0x11} // _
 )
 
 func handleDownloadProfile(ctx context.Context, conn *Conn, data []byte) error {
@@ -70,7 +69,7 @@ func download(ctx context.Context, conn *Conn, data []byte) error {
 	if len(parts) == 5 {
 		confirmationCode = string(parts[4])
 		if confirmationCode == "1" {
-			parts[4] = bytes.Replace([]byte("<confirmation_code>"), []byte("_"), GSMUnderscore, 1)
+			parts[4] = []byte("<confirmation_code>")
 			return errors.New(ErrRequireConfirmationCode + "\n" + string(bytes.Join(parts, GSMDollarSign)))
 		}
 	}

diff --git a/internal/cloud/util.go b/internal/cloud/util.go
@@ -2,7 +2,45 @@ package cloud
 
 import "unicode"
 
+var GSM7CharacterSet = map[rune]byte{
+	'@': 0x00,
+	'£': 0x01,
+	'$': 0x02,
+	'¥': 0x03,
+	'_': 0x11,
+	'!': 0x21,
+	'#': 0x23,
+	'%': 0x25,
+	'&': 0x26,
+	'(': 0x28,
+	')': 0x29,
+	'*': 0x2A,
+	'+': 0x2B,
+	',': 0x2C,
+	'-': 0x2D,
+	'.': 0x2E,
+	'/': 0x2F,
+	':': 0x3A,
+	';': 0x3B,
+	'<': 0x3C,
+	'=': 0x3D,
+	'>': 0x3E,
+	'?': 0x3F,
+}
+
 func ToTitle(s string) string {
 	r := []rune(s)
 	return string(unicode.ToUpper(r[0])) + string(r[1:])
 }
+
+func ToGSM7(b []byte) []byte {
+	var result []byte
+	for _, c := range b {
+		if v, ok := GSM7CharacterSet[rune(c)]; ok {
+			result = append(result, v)
+		} else {
+			result = append(result, c)
+		}
+	}
+	return result
+}
diff --git a/internal/config/config.go b/internal/config/config.go
@@ -4,6 +4,7 @@ import (
 	"errors"
 	"net"
 	"os"
+	"strings"
 )
 
 type Config struct {
@@ -44,7 +45,7 @@ func (c *Config) IsValid() error {
 
 func (c *Config) GetAdvertising() []byte {
 	if c.Advertising != "" {
-		return []byte("!! Advertising !! \n" + c.Advertising)
+		return []byte("!! Advertising !! \n" + strings.Replace(c.Advertising, "_br_", "\n", -1))
 	}
 	return []byte{}
 }