Any programmers around?

[Tom]

I know very little about programming, but I have a firmware file for my phone that needs 1 tiny ickle setting changing.

Basically, its a url for a software download. Is it possible to decode the file I have, and change that url, before I flash the phone? Is there any software I might use? The file appears to be in hex.

This is the kind of thing I'm looking at:

S345080001C008006050080131B0080001CC772424706006B6077723007E9607772396077F217F2377236036B6077F2360127F23772376248707600E0F67E801606E12E27F2166
S345080002006002606374227F202CBE24EE601260A312E47F1D601260B312E47F1B601260D312E47F19601260E312E47F177219731A7F19006E2070701924F0007D7E19821ECB
S34508000240842E830E05247F177E18841E820E600305247F16006D20F0F7B900000802C6540802C65C080032740802C658080003820800C184001000000010007C0800B1CC37
S34508000280008988650800330A08003408000003A108007364080043C8080072F808000DFC0800C640080060940800C64C080061042470007E122E73D07FCF810E121E014E96
S345080002C03F012A0E0141E0042A01E802121EF000014E12E2006E207000CF2470007E60AE7FC701BEE7FD006E207000CF24F0007C7EC473C412ED203D12E27FBE8C0E8D0D6D
S3450800030012E273C17FBCFFE912C201623D02016D1ED2006C20F000CF24709F00FFC977BB9207608735370E72E80360923472F02571B81227014716170F17E00362523472DA
S34508000340F01C0142610735470E72E80362623472F014620735570E72E80362723472F00D640735670E72E80360223472F006327735770E726072347201C201428F0020708A
S3450800038000CF2470007E7EA36047B70E60026007924EB23ED72E922EFFA9719F923EA10160042201E015739D12453C451C3587050F27E00A8715974EA785B73EA795B70E35
S345080003C0C755D72E8735972E200401440D14E7EC006E2070709324F0007D122D7F92122E014E2A0EE01412D273907F8212D2738F7F81870D327E357E16E70FE7E8057F7FB0

Does that make any kind of sense to anyone?

 

[TheJkWhoSaysNi]

Well, after using http://nickciske.com/tools/hex.php to decode it, I cant find a URL.

I ignored the S34508000** parts then converted the rest to ASCII. It's all strange characters. So either it's encrypted somehow, it doesnt use ASCII or there is no URL in there.

Maybe i'm completly off track and someone else who knows more about this than me can help, unfortunatly that's about as much as I know about hex.

 

[Tom]

Thanks, but its only a very small portion of the file (the full file is 10MB)

I got the following info from someone else:

Current installation won't work because the domain to retrieve the services midlet is hard-coded into the firmware and checked on installation.

You need to hexedit the firmware binary file and change "drei.at" to "three.co.uk"

Search for the ASCII string (2 occurrences):

" 687474703A2F2F6D6F62696C652E647265692E61742F68622F
74616C6F6**F6A6164732F"
this is equivalent to:
"h t t p : / / m o b i l e . d r e i . a t / h b / t a l o n / j a d s / "

Change the substring:

"647265692E6174"
this is equivalent to:
"d r e i . a t "

to:

"74687265652E636F2E756B"
this is equivalent to:
"t h r e e . c o . u k "

That may fix the problem of the incorrect URL, BUT there may be checksum problems now because the firmware file will be larger with the extra characters.

Note: the "**" above has been censored and should be "E 2" without the space
and there is no space between " and 68.....

 

[Shovel]

Well, as regards the checksumming you may want to check if there are any padding characters anywhere in the file, if so you could remove the relevant number of them to have the checksum equate correctly.

Has "someone else" not already done it that you could source it from?

 

[Tom]

There are quite a few people who have already flashed their phone. Hopefully, one of them will try it, if it works ok, I'll do mine. At the moment I have a fully functioning (old) firmware, and I don't want to risk being left with a piece of plastic instead of a phone

 

[stormrider]

What youve got there is a motorola s-record hex image
http://www.amelek.gda.pl/avr/uisp/srecord.htm
Its basically a format to describe the data to be flashed into the device.

 

[Tom]

Looks like somebody managed to do it. I'm waiting for a bit more info, then I'm gonna flash that bitch!*

http://www.3g.co.uk/3GForum/showthread.php?s=&threadid=4024&perpage=40&pagenumber=1


http://www.trippie.pwp.blueyonder.co.uk/a835_guide/



*bitch refers to phone

 

[Danya]

Well, as regards the checksumming you may want to check if there are any padding characters anywhere in the file, if so you could remove the relevant number of them to have the checksum equate correctly.

Has "someone else" not already done it that you could source it from?

Checksums don't work on size only, they also check content. You would have to genrate a new checksum for the file based on the new data.