SOAP asciihex encoding - soap

I would really appreciate if anyone can help me with this, I looked a bit into this issue on the internet but no results.
As a client, I'm retrieving a SOAP message trough a GET request, the message is encoded trough "asciihex" encoding.
The documentation says this - "If the file is downloaded, it will be encoded and the client has to decode it to read it correctly. Currently, CCon supports just asciihex encoding mode. If this mode is used, every single original byte is encoded as a sequence of two characters representing it in hexadecimal. So, if the original byte was 0x0a, the transmitted bytes are 0x30 and 0x41 (‘0’ and ‘a’ in ASCII)."
Problem comes with encoding this message, I don't have any idea how to translate this into an intelligible text.
The messaging protocol used for this is SOAP, I'm testing this using SoapUI.

Related

Why Base64 is used "only" to encode binary data?

I saw many resources about the usages of base64 in today's internet. As I understand it, all of those resources seem to spell out single usecase in different ways : Encode binary data in Base64 to avoid getting it misinterpreted/corrupted as something else during transit (by intermediate systems). But I found nothing that explains following :
Why would binary data be corrupted by intermediate systems? If I am sending an image from a server to client, any intermediate servers/systems/routers will simply forward data to next appropriate servers/systems/routers in the path to client. Why would intermediate servers/systems/routers need to interpret something that it receives? Any example of such systems which may corrupt/wrongly interpret data that it receives, in today's internet?
Why do we fear only binary data to be corrupted. We use Base64 because we are sure that those 64 characters can never be corrupted/misinterpreted. But by this same logic, any text characters that do not belong to base64 characters can be corrupted/misinterpreted. Why then, base64 is use only to encode binary data? Extending the same idea, when we use browser are javascript and HTML files transferred in base64 form?
There's two reasons why Base64 is used:
systems that are not 8-bit clean. This stems from "the before time" where some systems took ASCII seriously and only ever considered (and transferred) 7bits out of any 8bit byte (since ASCII uses only 7 bits, that would be "fine", as long as all content was actually ASCII).
systems that are 8-bit clean, but try to decode the data using a specific encoding (i.e. they assume it's well-formed text).
Both of these would have similar effects when transferring binary (i.e. non-text) data over it: they would try to interpret the binary data as textual data in a character encoding that obviously doesn't make sense (since there is no character encoding in binary data) and as a consequence modify the data in an un-fixable way.
Base64 solves both of these in a fairly neat way: it maps all possible binary data streams into valid ASCII text: the 8th bit is never set on Base64-encoded data, because only regular old ASCII characters are used.
This pretty much solves the second problem as well, since most commonly used character encodings (with the notable exception of UTF-16 and UCS-2, among a few lesser-used ones) are ASCII compatible, which means: all valid ASCII streams happen to also be valid streams in most common encodings and represent the same characters (examples of these encodings are the ISO-8859-* family, UTF-8 and most Windows codepages).
As to your second question, the answer is two-fold:
textual data often comes with some kind of meta-data (either a HTTP header or a meta-tag inside the data) that describes the encoding to be used to interpret it. Systems built to handle this kind of data understand and either tolerate or interpret those tags.
in some cases (notably for mail transport) we do have to use various encoding techniques to ensure text doesn't get mangles. This might be the use of quoted-printable encoding or sometimes even wrapping text data in Base64.
Last but not least: Base64 has a serious drawback and that's that it's inefficient. For every 3 bytes of data to encode, it produces 4 bytes of output, thus increasing the size of the data by ~33%. That's why it should be avoided when it's not necessary.
One of the use of BASE64 is to send email.
Mail servers used a terminal to transmit data. It was common also to have translation, e.g. \c\r into a single \n and the contrary. Note: Also there where no guarantee that 8-bit can be used (email standard is old, and it allowed also non "internet" email, so with ! instead of #). Also systems may not be fully ASCII.
Also \n\n. is considered as end of body, and mboxes uses also \n>From to mark start of new mail, so also when 8-bit flag was common in mail servers, the problems were not totally solved.
BASE64 was a good way to remove all problems: the content is just send as characters that all servers must know, and the problem of encoding/decoding requires just sender and receiver agreement (and right programs), without worrying of the many relay server in between. Note: all \c, \r, \n etc. are just ignored.
Note: you can use BASE64 also to encode strings in URL, without worrying about the interpretation of webbrowsers. You may see BASE64 also in configuration files (e.g. to include icons): special crafted images may not be interpreted as configuration. Just BASE64 is handy to encode binary data into protocols which were not designed for binary data.

Did anyone ever heard about asciihex encoding?

this type of encoding is used in soap messages...
I'm receiving a message encoded in ASCIIHEX and I don't have any ideas on how this encoding actually works although I have the clear description of the encoding method:
"If this mode is used, every single original byte is encoded as a sequence of two characters representing it in hexadecimal. So, if the original byte was 0x0a, the transmitted bytes are 0x30 and 0x41 (‘0’ and ‘a’ in ASCII)."
The buffer received : "1f8b0800000000000000a58e4d0ac2400c85f78277e811f2e665329975bbae500f2022dd2978ff95715ae82cdcf9415efec823c6710247582d5965c32c65aab0f5fc0a5204c415855e7c190ef61b34710bcdc7486d2bab8a7a4910d022d5e107d211ed345f2f37a103da2ddb1f619ab8acefe7fdb1beb6394998c7dfbde3dcac3acf3f399f3eeae152012e010000"
The actual file contains this : "63CD13C1697540000000662534034000030000120011084173878R 00000001000018600050000000100460000009404872101367219 000000000000 DNSO_038114 000000002001160023Replacem000000333168625 N0000 00000000"
The provider sent me the file that contains the string above. I tried to start from the buffer string and get the same result as the one sent by the provider but no results. I also tried searching after this "asciihex" encoding and same. If someone knows anything about this encoding or can give me any advice I would really appreciate it. I have pretty much no experience with SOAP services.
Based on the comments above, it's possible the buffer is compressed. It starts with 1F 8B which is a signature for GZIP compression. See the following list of signatures.
Write the bytes that correspond to the hex strings into a file. Name that file with a gz or tar.gz extension and try to extract it or open it with some file archiver tool.
Another thing you could try would be to not send the Compress element in your request, assuming it's an optional field and you can do that. If you can, check if the buffer changes and has the proper length and you can see similar patterns as the original content (for those zeros at the end, for example).

What is the use of Binary encoding when we have Character encoding?

I use to think that the use of binary encoding is because every device has its way to interpret bytes. Thus if a router sends a bit as some significant information other router might treat this byte as a parity byte or something else...
But isn't it all already covered in character encoding?? I mean character encoding tells what byte is representing which character, right? (Or am I missing something? ) Isn't the information about character encoding(like UTF-8) enough for devices to read bytes directly? If yes why would anyone want to encode this (Using something like base64) cause it will increase the size of the data required to be transferred.

How to auto detect a String encoding?

I have a String which contains some encoded values in some way like Base64.
The problem is that I really don't know if it's actually Base64 (there are A-Z, a-z. 0-9, +, /) so it can be some any other code that i'm not familiar with.
Is there a way or any other online site to send him an encoded input and it can tell me in which code is it?
NOTE:
I'm not asking how to know if my String is UTF-8 or iso-8859-1 or something like that.
What I need is to know in which is my code is encoded.
EDIT:
To be more clear,
I need something to get an input like: 23Nzi4lUE4qlc+Pmc3blWMS1Irmgo3i8UTQHhoL7VyzqpEV/i9bDhoiteZ0a7/TqcVSkrXR89V2Yj7tEFDGJx4gvWEBs= this is the encoded String that I have.
The output should be the type of the encoded String and it's decoding like:
Base64 -> "Big yellow fish is swimming in the tube."
Maybe there is some program which get's an input and tries to decode it with a list of coding types (Base64 and etc.). The output doesn't really matter because it's the users decision if it's good or not.
This site handles base64 de/encoding.
Since Base64 is just one instance of a class of encoding schemes ( specifically, encoding a bit stream as base_<n> number ), you probably will never fare better than testing for just a couple of standard encoding schemes.
You either check the well-formedness of the encoding scheme or try to decode without getting an error thrown using a web service or your own code.
In (possibly pathological) cases there will be more than one encoding scheme for which a given octet stream will successfully decode.
Best practice would be to take the effort invested into setting up the verification to committing the data provider to one (or 'a few') encoding(s) first (won't always be possible, of course).

How to send text in UTF-8 using Indy TIdTCPServer in c++ builder

My client j2me application reading text input stream using UTF-8
reader = new InputStreamReader(in,"UTF-8");
and my server when gets connected sends text using this statement
AContext->Connection->IOHandler->WriteLn(cxMemo1->Text,TEncoding::UTF8);
but result text showing weird characters like ?????????????????????????? ?????????????
Where I'm doing wrong?
also when i tried to load from utf-8 encoding data file in such a way
AContext->Connection->IOHandler->WriteFile("c:\\fids.xml");
it's all the same!
Indy 10 completely supports UTF-8 encoding. I've myself worked with it's TIdFTP component & successfully uploaded Unicode text files. From what I can make of it:
Your connection/transfer type is set to ftASCII rather than ftBinary.
Your J2ME applet/Host platform does not suport UTF-8
'?' characters occur when data is going through a Unicode-to-Ansi conversion to an Ansi charset that does not support the Unicode characters being converted.
What version of C++Builder are you using? In versions prior to CB2009, you should tell Indy the encoding of the AnsiString data that you are passing in. Indy defaults to ASCII (ie: TIdTextEncoding::ASCII) for most String-based operation. That can be overridden when needed, either with optional AAnsiEncoding parameters, the TIdIOHandler::DefAnsiEncoding property, or the global Idglobal::GIdDefaultAnsiEncoding setting. If you do not specify the correct encoding, the AnsiString data may not be converted to Unicode correctly before then being converted to UTF-8. For example:
AContext->Connection->IOHandler->WriteLn(cxMemo1->Text, TIdTextEncoding_UTF8, TTIdTextEncoding_Default);
Or:
AContext->Connection->IOHandler->DefAnsiEncoding = TIdTextEncoding_Default;
AContext->Connection->IOHandler->WriteLn(cxMemo1->Text, TIdTextEncoding_UTF8);
You can optionally also use the TIdIOHandler::DefStringEncoding property if you do not want to specify the UTF-8 encoding on every call:
AContext->Connection->IOHandler->DefStringEncoding = TIdTextEncoding_UTF8;
AContext->Connection->IOHandler->WriteLn(cxMemo1->Text);
Now, with that said, the fact that WriteFile() is also sending data that J2ME is not handling correctly tells me that Indy is not the root of the issue. WriteFile() simply dups the raw file data as-is to the connection without any interpretation at all. If you send a UTF-8 encoded file, then UTF-8 encoded octets will be sent to J2ME.
I suggest you use a packet sniffer, such as Wireshark, to verify the data that Indy is sending. That will tell you for sure whether Indy is really at fault or not.
*PS: notice in the examples above that I use Indy's TIdTextEncoding macros instead of TEncoding directly. This is because Indy's TIdTextEncoding logic works around some bugs in Embarcadero's TEncoding classes. Also, we're going to phase out direct support for TEncoding in Indy 11 and expand on TIdTextEncoding so Indy has more control than Embarcadero offers.