Find the XML structure of the message to be
sent
Here’s a sample one, I will
add the references on how to find the basic XML structure and where to find
them,
<?xml version="1.0"?>
<!DOCTYPE si PUBLIC "-//WAPFORUM//DTD SI 1.0//EN"
"http://www.wapforum.org/DTD/si.dtd">
<si>
<indication href=http://blog.0x7678.com/ si-id="bin">
hack random
</indication>
</si>
Now to convert to WBXML
HexCode Meaning
02 WBXML Version 1.2
05 SI 1.0 Public Identifier
6A Charset UTF-8
00 String table length = 0
45 <SI>
C6 <indication>
0C href=”http://
03 String
starts
00 String
ends
07 Action
attribute (signal – medium)
01 Ends
of attributes, now the content
03 String
starts
*
446576446F744D6F62692069732046756E2021 hack
random
00 String
ends
01 </indication>
01 </SI>
* These are strings used to
pass contents to the SI, each character in the string is converted to its
hexadecimal representation.
** “6532” is to be considered
a string of characters and not a number, so don’t use the calculator to convert
this number
Our body is, putting all the
numbers together:
02056A0045C60C037777772E6465762E6D6F62692F69735F66756E2E68746D6C0<br/>011033635333200070103446576446F744D6F62692069732046756E2021000101
(which
is 130 chars)
PREPARE THE UDH
Preparing
the UDH is pretty easy. Just start with “06
05 04” and then add the port numbers. Eg WAP push messages uses
“destination port” 2948 while source port is 9200. Convert decimal port numbers
to hexadecimal formats, so 2948 becomes 0B84 and 9200 becomes 23F0. Magically,
the UDH is : 06 05 04 0B 84 23 F0
SENDS THE SMS AND
THE UDH
Now,
what you need to do with this? Pretty simple, just put everything together and
the SMS is ready to be sent.
<UDH>
+ <BODY>
UDH: 06 05 04 0B 84 23 F0<br/>BODY:
02056A0045C60C037777772E6465762E6D6F62692F69735F66756E2E68746D6C0
The complete message is then:
<span><strong>0605040B8423F0</strong><br/>02056A0045C60C037777772E6465762E6D6F62692F69735F66756E2E68746D6C0<br/>011033635333200070103446576446F744D6F62692069732046756E2021000101
Which is 137 chars long (hey, it’s a
binary SMS,
and my favorite language Java uses UTF-8 encoding for binary messages, so the
limit for 1 SMS is 140 chars, aren’t we cool?)
For
now that’s what I will teach, this however is a beginning to something bigger
such as the OpenBTS am optimizing by adding binary SMS support.
NB: the above WBXML is only an example the converted WBXML is not as on my blog (for security purposes, link to original document can be found from the decoded wbxml :) cheers)
NB: the above WBXML is only an example the converted WBXML is not as on my blog (for security purposes, link to original document can be found from the decoded wbxml :) cheers)
