Extraction of firmware 7390

[earoq.12]

Hi,
I have downloaded the latest firmware of 7390 from avm site.
when i try to extract the firmware with fwmod i get the following error :
ERROR: modunpack_autodetect_fs: failed to detect file system type of 'unpacked_firmware / original / firmware / var / tmp / filesystem.image'.
As well as when i look into the directory after running the command, i see the size of "filesystem.image" is 0 bytes.

 

[PeterPawn]

The size of zero bytes is correct - this device uses a combination of kernel and filesystem image and both of them are concatenated in the "kernel.image" file.

I'd bet, you've selected the wrong device type with "make menuconfig" - the firmware structure infos are selected with the right model.

For a 7390 device, the scripts should not try to unpack the original "filesystem.image" file - instead the "kernel.image" file gets splitted into the concatenated parts, around this line: https://github.com/Freetz/freetz/blob/master/fwmod#L451

 

[earoq.12]

Hi Peter,
Thanks for the answer.
This are the instruction i have done:
1. mkdir tmp && cd tmp
2. tmp_umask = $ (umask)
3. Download the image into the directory with git (it will create a new directory)
4. umask $ tmp_umask
5. cd into the the new directory.
6. make menuconfig and then exit
7. make tools
8. using the fwmod
what am i doing wrong ?

 

[PeterPawn]

Did you select your device model in step 6?

Default value is a 7490 device, which uses a different firmware structure.

 

[earoq.12]

Yes you right. After i have changed the type, it worked to.
If you can help me in another issue i will glad.
I have the 7390 and i want a telnet access, how do i connect to the device ?

 

[PeterPawn]

I'm unable to understand the question ... due to the lack of needed information.

Are you using a full Freetz image (it contains an own GUI and the "telnetd" daemon has to be started via this interface first) or are you using only the "repacking approach", where kernel and filesystem are unpacked, may be changed and get packed again by "fwmod"? Using "fwmod" there are two different options, too - using "fwmod -u" and "fwmod -p" at the one hand and using "no-freetz" mode of "fwmod" on the other side.

Without knowledge about the option you've used, there's no possibility to provide any (valid) hint ... at least not without a fresh, "whole" description, which exists otherwards already and doesn't need any duplicate.

 

[earoq.12]

My final purpose is to enable telnet. As i understand, there are two methods to enable telnet.
1. unpacking the firmware from avm website and changing the "install" file to enable telnet, then repacking it again with fwmod and use the web interface to upload the modified firmware.
2. This method you wrote https://www.ip-phone-forum.de/threads/fritz-box-7580-firmware-153-06-90-telnet-service-freischalten-geht-auch-für-7560-und-7590.296678/
Am i correct ?

 

[PeterPawn]

No, the first option is wrong in the aspect, that it should have something to do with an "install" file.

The second option could really work, but it's more eligible for newer FRITZ!Box models and your 7390 is a rather old one.

You may/should use the "no-freetz" approach - it requires appropriate settings from "make menuconfig" (read this description first: https://freetz.github.io/wiki/help/...ck_fw.html#Verwendungvonfwmodimnofreetz-Modus - there's no English version, but you may use an online translation service, e.g. DeepL) and then it will do the rest for you.

You get a complete image (as "kernel.image" within a TAR file - extract this one first and don't try to write the TAR file itself), which has to be flashed to the partition MTD1 via EVA loader of your device.

After the device was started with the new firmware image, you've to activate the "telnetd" service via phone code (it still works on a 7390 with firmware versions < 07.xx and you may use the "dial service" with a phonebook entry, if there's no physical phone connected to the box - only POTS and ISDN devices are usable to enter the code(s)) and then you may use a telnet client program to connect to the FRITZ!Box device.

 

[earoq.12]

are u sure for 100% the second method will not work on 7390 ?
I prefer to stay with the original firmware and not with the "no-freetz" approach

 

[PeterPawn]

Hmm ...

are u sure for 100% the second method will not work on 7390 ?

vs.

The second option could really work, but it's more eligible for newer FRITZ!Box models and your 7390 is a rather old one.

Do you see the contradiction?

Surely it works to create the symlink for "/usr/sbin/telnetd" and rely on the existing start mechanisms, as described by me above.

But the whole description, you've linked to in #7, uses a different method to unpack the firmware and to pack it later again. The only part, which is usable from the linked thread, is the "ln -s" command to create the symlink in the unpacked filesystem structure.

The description for 7560/7580/7590 may be used to concatenate the kernel and filesystem image, too (wow, the 2nd common step) ... but there's another call needed to pack the firmware as SquashFS image, with other options and another "mksquashfs" binary, which provides "lzma" compression for SquashFS version 3 with "big endian" scheme for data storage is needed, too - and your only method to install the created image is still to flash it via EVA and this works completely different on a 7390, as I wrote above already.

Furthermore you have to split the "kernel.image" file into the real kernel image and the SquashFS image yourself - also a task, where you should know anything about the different structures of such a "combined image", even if the SquashFS tools from the Freetz toolchain may unpack a filesystem image with a NMI vector area without any further problems (but do not try this with tools from another source, without the proper patches to their source codes). You'll need the "plain kernel" later to create a "combined image" again ... pay attention to the correct padding of the kernel, 'cause the filesystem image has to start at a 256-byte boundary in the flash memory.