MMS + Forward Lock parts : boundary of Forward Lock with the '=' ch...

MMS + Forward Lock parts : boundary of Forward Lock with the '=' ch... SearchSearch
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Anonymous
 
Posted on Thursday, April 14, 2005 - 03:20 pm:   

Hi,
I'm trying to use a Forward Lock object in a MMS (submitted by SMTP to the MMSC).
The boundary of the FL body should be encoded as a parameter, which is properly done.
However, if this boundary contains specific chars (as e.g. '='), it should be encoded as Quoted-string (WSP specification), which does not seem to be the case.
Attached is the Test Sample I'm talking about.

text/htmlSample Forward Lock with boundary containing '='
Test MMS Equal.MMS (3.7 k)


Am I doing something wrong here?

Thanks for the support.
Best Regards
Fred
Bryce Norwood - NowSMS Support
Board Administrator
Username: Bryce

Post Number: 4341
Registered: 10-2002
Posted on Thursday, April 21, 2005 - 09:40 pm:   

Hi Fred,

Have you tested with different boundary values to confirm that you are having a problem with boundaries that include "="?

I don't see anything in the WSP specification that would indicate that the present of the "=" character would require that the boundary value be encoded as Quoted-String.

Can you give me a specific section reference?

Let's see ...

Section 8.4.2.4 gives the rules for parameter encoding. "boundary" would be an "Untyped-parameter". The parameter name (boundary) would be encoded as "Token-text", while parameter value would be encoded as "Untyped-value".

"Untyped-value" can be EITHER "Integer-value" or "Text-value". "Text-value" can be EITHER "No-value", "Token-text" or "Quoted-string".

"Token-text" is basically a text string terminated with null. While "Quoted-string" is the same text string but starts with a quote (").

So why would you choose one format or the other?

Well, it refers back to RFC 2616 for a definition of token ... and sure enough, the "=" character canNOT be included in a token.

So you are correct, and my original assumption here is incorrect.

Drop me an e-mail, and I should be able to supply you with an update to MMSCOMP that addresses this problem. Send an e-mail to nowsms@now.co.uk, with "Attention: Bryce" in the subject line, referencing this thread.

-bn
kondru
Unregistered guest
Posted on Monday, July 18, 2005 - 08:24 pm:   

Hi Guys,
I am planingto send MMS to mobile as DRM Forward lock protected by using AIR CARD.Please give ur valuable suggestins.
Simon Grime
New member
Username: Simong

Post Number: 1
Registered: 08-2005
Posted on Tuesday, August 16, 2005 - 03:26 pm:   

Hi
Firstly, my technical knowledge is limited here. However, I work in a digital marketing communications business and we have a client who is a mobile handset manufacturer. They want to know how to encrypt content that is loaded onto an SD card for use in a handset, so that the content cannot then be uploaded to the web or copied to a PC etc, by the consumer. They have mentioned "Forward lock" and want advice on this - or any other method of encryption to achive this anyone got any ideas pls - urgently?

Thanks

Simon
Bryce Norwood - NowSMS Support
Board Administrator
Username: Bryce

Post Number: 4776
Registered: 10-2002
Posted on Tuesday, August 16, 2005 - 04:42 pm:   

Hi Simon,

NowSMS supports sending out "forward lock" content via MMS or WAP Push.

When a mobile device receives content with the "forward lock" attribute set, the mobile device is supposed to respect that attribute, allowing the user to view the content, but not to copy or forward the content.

Of course, if a device does not support "forward lock", then it would not understand the content at all, and would not be able to display it.

But I'm talking about sending content via MMS or WAP. When the device saves such content to permanent storage, such as an SD card ... then it is up to that device how it stores the content in a protected format.

For example, I've got a SonyEricsson phone with a Memory Stick. I sent a forward lock file to the device, and saved it to the memory stick.

If I put the memory stick in the PC, I can see that there is a file there which contains the forward lock content ... but the file is scrambled, and I cannot access it from the PC. I can access it just fine from the phone, but I do not have any option to forward it on the phone.

How this applies to your question though ... I'm not entirely sure. I'm talking about sending forward lock via MMS or WAP Push. You're talking about how forward lock files are stored on an SD card ... and that is really up to the manufacturer.

-bn
Simon Grime
New member
Username: Simong

Post Number: 2
Registered: 08-2005
Posted on Tuesday, August 16, 2005 - 05:10 pm:   

Hi Bryce

Having re-read your comments - do you know how can forward-lock be applied to file content on the SD cards?

Simon
Simon Grime
New member
Username: Simong

Post Number: 3
Registered: 08-2005
Posted on Tuesday, August 16, 2005 - 05:14 pm:   

Hi Bryce

Thanks for your help

Having - re-read your comments - a couple of other points if I may?

Firstly, how do you apply the forward-lock attribute to file content that goes on the SD card?

Also, following your comments, does this mean that if the handset sending a message does not support forward-lock, that this user could send the content from the SD card to other users who also do not support forward-lock? Similarly, if the handsets do not support forward-lock, are there are other ways of encrypting the content on the SD card so that it cannot be copied?

Thanks in advance for help

Simon
Bryce Norwood - NowSMS Support
Board Administrator
Username: Bryce

Post Number: 4798
Registered: 10-2002
Posted on Friday, August 26, 2005 - 10:59 pm:   

Hi Simon,

I have absolutely no idea how the attribute gets applied on an SD card.

My belief is that it is handset manufacturer specific.

I don't have access to any phones that support forward lock and use SD cards at the moment. But as a quick test, I sent a forward lock picture in an MMS message to a SonyEricsson K750i. I received it on the phone, and saved it to the memory stick.

I then popped the memory stick into a laptop. I could see the forward locked file appear in the directory listing, but opening the file just resulted in a bunch of garbage, nothing recognisable.

What I don't know, is if I moved it to another phone, whether it would recognise the file or not. (I assume it would.)

I'd guess that things are similar with an SD card. Whatever format the phone uses for a forward locked file on the SD card would have to be a format that would not be recognised if the SD card were inserted into a PC card reader. I don't know if there is a standard for this format, or if each vendor has implemented their own approach. (I suspect the latter.) So, you'd probably need the mobile handset manufacturer have their techies advise you on the format.

-bn