PDU strings from mobile phones can be 08 91 68 31 08 20 05 05 F0 11 00 D 91 68 31 58 81 27 64 F8 00 06 C8 32 9 B FD 0E 01
Contrast with the norms and analyze them concretely:___________
08. Length of SMSC Address Information. A total of 8 8 bytes (including 91)
91. SMSC Address Format (TON/NPI). Use International Format Number (with'+'in front)
68 31 08 20 05 05 F0 SMSC address 8613800250500, make up an even number of'F'
11. Basic parameters (TP-MTI/VFP) are sent, and TP-VP is in relative format.
00. Message Baseline Value (TP-MR) 0
0D. Number of target address digits. Total 13 decimal digits (excluding 91 and'F')
91. Target Address Format (TON/NPI). Use International Format Number (with'+'in front)
68 31 58 81 27 64 F8 Target Address (TP-DA) 8613851872468, complement'F'to make even number, BCD encoding, low-high bit mode
00) Protocol Identification (TP-PID) is a common GSM type, point-to-point mode.
00) User Information Coding (TP-DCS) 7-bit Coding
00) Term of validity (TP-VP) 5 minutes
06) User Information Length (TP-UDL). Actual Length 6 Bytes
C8 329B FD 0E 01 User Information (TP-UD) "Hello!"
0891683108100005F0 31 00 0B 81 3129503323F1 00 08 A8 0C 4F6060F3776189C94E865427
Analysis
Segmentation
Meaning
Explanation
08
The length of SMSC address information
A total of 8 octets (including 91)
91
SMSC Address Format (TON/NPI)
In international format (with'+'before), 81 indicates no+
683108100005F0
SMSC address
8613800100500, complement'F'to compose even number of bcd codes
31
Basic parameters (TP-MTI/VFP)
Send, TP-VP in relative format. sign
00
Message Baseline Value (TP-MR)
0
0D
Number of target addresses
A total of 13 decimal digits (excluding 91 and `F')
81
Target Address Format (TON/NPI)
In international format (with'+'in front), 81 means no'+'.
3129503323F1
Target address (TP-DA)
8613851872468, complement'F'to make even number, BCD coding, low-high bit mode
00
Protocol Identification (TP-PID)
General GSM type, point-to-point mode
08
User Information Coding (TP-DCS)
16-bit coding, UCS2 coding
A8
Validity period (TP-VP)
2 days
0C
User Information Length (TP-UDL)
12 bytes in length
4F6060F3776189C94E865427
User Information (TP-UD)
"You go to bed!"
public static String hexString7ToString(String s){
if (StringUtils.isEmpty(s))
throw new IllegalArgumentException("this hexString must not be empty");
byte[] dataArray = hexStr2ByteArray(s);
String str = decode7bit(dataArray);
return str;
}
/**
* 7-bit Decode
* @param data
* @return
*/
public static String decode7bit(byte[] d){
byte[] other_mask ={(byte) 0x80,(byte) 0xc0,(byte) 0xe0,(byte) 0xf0,(byte) 0xf8,(byte) 0xfc,(byte) 0xfe};
byte[] my_mask = {0x7f,0x3f,0x1f,0x0f,0x07,0x03,0x01};
byte other = 0;
byte temp = 0;
StringBuffer sb = new StringBuffer();
for(int i=0;i<d.length;i++){
int index = i%7;
temp = d[i];
//Get my data
d[i] = (byte) (d[i]&my_mask[index]);
d[i] = (byte) (d[i] << index);
if(index != 0){
d[i] = (byte) (d[i]&other_mask[7-index]);
other = (byte) (other>>(8-index));
other = (byte) (other&my_mask[7-index]);
d[i] = (byte) (d[i] | other);
}
//Take the next data information away first
other = (byte) (temp&other_mask[index]);
sb.append((char)d[i]);
if(index == 6){
other = (byte) (other>>1);
other = (byte) (other & 0x7f);
sb.append((char)other);
}
}
return sb.toString();
}
public static byte[] hexStr2ByteArray(String hexString) {
//TODO Hex.decode(hexString);
if (StringUtils.isEmpty(hexString))
throw new IllegalArgumentException("this hexString must not be empty");
hexString = hexString.toLowerCase();
final byte[] byteArray = new byte[hexString.length() / 2];
int k = 0;
for (int i = 0; i < byteArray.length; i++) {
//Because it's hexadecimal, it only takes up to four bits at most. Converting to bytes requires two hexadecimal characters, with high bits first.
//Converting hex to byte "&" operation to prevent automatic expansion of negative numbers
// Converting hex to byte actually takes up only four bits, and then shifts the top four to the right.
// Then "|" operates four bits lower to get two hexadecimal digits converted into a byte.
//
byte high = (byte) (Character.digit(hexString.charAt(k), 16) & 0xff);
byte low = (byte) (Character.digit(hexString.charAt(k + 1), 16) & 0xff);
byteArray[i] = (byte) (high << 4 | low);
k += 2;
}
// System.out.println ("Hexadecimal plaintext string converted to hexadecimal byte array:" +byteArray);
16-bit
public static String DecodeUCS2(String src) {
byte[] bytes = new byte[src.length() / 2];
for (int i = 0; i < src.length(); i += 2) {
try {
bytes[i / 2] = (byte) (Integer
.parseInt(src.substring(i, i + 2), 16));
} catch (Exception e) {
System.out.println("Exceptional characters:"+src.substring(i, i + 2));
}
}
String reValue="";
try {
reValue = new String(bytes, "UTF-16BE");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return reValue;
}