implemented ucs2 encoding for MO messages (in order to deal with cyri…

…llic alphabet)

smsc.go

@@ -11,6 +11,7 @@ import (
  "strconv"
  "sync"
  "time"
+ "unicode/utf8"
 )
 
 // command id
@@ -38,6 +39,15 @@ const (
  STS_ALREADY_BOUND = 0x00000005
 )
 
+// data coding
+
+const (
+ CODING_DEFAULT = 0x00
+ CODING_UCS2 = 0x08
+)
+
+// optional parameters
+
 const (
  TLV_RECEIPTED_MSG_ID = 0x001E
  TLV_MESSAGE_STATE = 0x0427
@@ -94,30 +104,28 @@ func (smsc *Smsc) BoundSystemIds() []string {
 }
 
 func (smsc *Smsc) SendMoMessage(sender, recipient, message, systemId string) error {
- var conn net.Conn
- receiveMo := false
+ var session *Session = nil
  for _, sess := range smsc.Sessions {
  if systemId == sess.SystemId {
- conn = sess.Conn
- receiveMo = sess.ReceiveMo
+ session = &sess
  }
  }
 
- if conn == nil {
+ if session == nil {
  log.Printf("Cannot send MO message to systemId: [%s]. No bound session found", systemId)
  return fmt.Errorf("No session found for systemId: [%s]", systemId)
  }
 
- if !receiveMo {
+ if !session.ReceiveMo {
  log.Printf("Cannot send MO message to systemId: [%s]. Only RECEIVER and TRANSCEIVER sessions could receive MO messages", systemId)
  return fmt.Errorf("Only RECEIVER and TRANSCEIVER sessions could receive MO messages")
  }
 
  // TODO implement UDH for large messages
  shortMsg := truncateString(message, 70) // just truncate to 70 symbols
  var tlvs []Tlv
- moMessage := deliverSmPDU(sender, recipient, shortMsg, rand.Int(), tlvs)
- if _, err := conn.Write(moMessage); err != nil {
+ moMessage := deliverSmPDU(sender, recipient, toUcs2Coding(shortMsg), CODING_UCS2, rand.Int(), tlvs)
+ if _, err := session.Conn.Write(moMessage); err != nil {
  log.Printf("Cannot send MO message to systemId: [%s]. Network error [%v]", systemId, err)
  return fmt.Errorf("Cannot send MO message. Network error")
  } else {
@@ -203,6 +211,12 @@ func handleSmppConnection(smsc *Smsc, conn net.Conn) {
  }
  log.Printf("submit_sm from system_id[%s]\n", systemId)
 
+ if receiver {
+ respBytes = headerPDU(SUBMIT_SM_RESP, STS_INV_BIND_STS, seqNum)
+ log.Printf("error handling submit_sm from system_id[%s]. session with bind type RECEIVER cannot send requests", systemId)
+ break
+ }
+
  idxCounter := 0
  nullTerm := []byte("\x00")
 
@@ -249,24 +263,20 @@ func handleSmppConnection(smsc *Smsc, conn net.Conn) {
  // prepare submit_sm_resp
  msgId := strconv.Itoa(rand.Int())
 
- if receiver {
- respBytes = headerPDU(SUBMIT_SM_RESP, STS_INV_BIND_STS, seqNum)
- } else {
- respBytes = stringBodyPDU(SUBMIT_SM_RESP, STS_OK, seqNum, msgId)
-
- if registeredDlr != 0 {
- go func() {
- time.Sleep(2000 * time.Millisecond)
- now := time.Now()
- dlr := deliveryReceiptPDU(msgId, now, now)
- if _, err := conn.Write(dlr); err != nil {
- log.Printf("error sending delivery receipt to system_id[%s] due %v.", systemId, err)
- return
- } else {
- log.Printf("delivery receipt for message [%s] was send to system_id[%s]", msgId, systemId)
- }
- }()
- }
+ respBytes = stringBodyPDU(SUBMIT_SM_RESP, STS_OK, seqNum, msgId)
+
+ if registeredDlr != 0 {
+ go func() {
+ time.Sleep(2000 * time.Millisecond)
+ now := time.Now()
+ dlr := deliveryReceiptPDU(msgId, now, now)
+ if _, err := conn.Write(dlr); err != nil {
+ log.Printf("error sending delivery receipt to system_id[%s] due %v.", systemId, err)
+ return
+ } else {
+ log.Printf("delivery receipt for message [%s] was send to system_id[%s]", msgId, systemId)
+ }
+ }()
  }
  }
  case DELIVER_SM_RESP: // deliver_sm_resp
@@ -342,10 +352,10 @@ func deliveryReceiptPDU(msgId string, submitDate, doneDate time.Time) []byte {
  msgStateTlv := Tlv{TLV_MESSAGE_STATE, 1, []byte{2}} // 2 - delivered
  tlvs = append(tlvs, msgStateTlv)
 
- return deliverSmPDU("", "", deliveryReceipt, rand.Int(), tlvs)
+ return deliverSmPDU("", "", []byte(deliveryReceipt), CODING_DEFAULT, rand.Int(), tlvs)
 }
 
-func deliverSmPDU(sender, recipient, shortMessage string, seqNum int, tlvs []Tlv) []byte {
+func deliverSmPDU(sender, recipient string, shortMessage []byte, coding byte, seqNum int, tlvs []Tlv) []byte {
  // header without cmd_len
  header := make([]byte, 12)
  binary.BigEndian.PutUint32(header[0:], uint32(DELIVER_SM))
@@ -377,19 +387,19 @@ func deliverSmPDU(sender, recipient, shortMessage string, seqNum int, tlvs []Tlv
  buf.WriteByte(0)
  }
 
- buf.WriteByte(0) // esm class
- buf.WriteByte(0) // protocol id
- buf.WriteByte(0) // priority flag
- buf.WriteByte(0) // sched delivery time
- buf.WriteByte(0) // validity period
- buf.WriteByte(0) // registered delivery
- buf.WriteByte(0) // replace if present
- buf.WriteByte(0) // data coding
- buf.WriteByte(0) // def msg id
+ buf.WriteByte(0)  // esm class
+ buf.WriteByte(0)  // protocol id
+ buf.WriteByte(0)  // priority flag
+ buf.WriteByte(0)  // sched delivery time
+ buf.WriteByte(0)  // validity period
+ buf.WriteByte(0)  // registered delivery
+ buf.WriteByte(0)  // replace if present
+ buf.WriteByte(coding) // data coding
+ buf.WriteByte(0)  // def msg id
 
  smLen := len(shortMessage)
  buf.WriteByte(byte(smLen))
- buf.WriteString(shortMessage)
+ buf.Write(shortMessage)
 
  for _, t := range tlvs {
  tlvBytes := make([]byte, 4)
@@ -418,3 +428,21 @@ func truncateString(input string, maxLen int) string {
  }
  return result
 }
+
+func toUcs2Coding(input string) []byte {
+ // not most elegant implementation, but ok for testing purposes
+ l := utf8.RuneCountInString(input)
+ buf := make([]byte, l*2) // two bytes per character
+ idx := 0
+ for len(input) > 0 {
+ r, s := utf8.DecodeRuneInString(input)
+ if r <= 65536 {
+ binary.BigEndian.PutUint16(buf[idx:], uint16(r))
+ } else {
+ binary.BigEndian.PutUint16(buf[idx:], uint16(63)) // question mark
+ }
+ input = input[s:]
+ idx += 2
+ }
+ return buf
+}