Hacking a TCD 1400060: quick question

[hopefulboydy]

Hi,

I have 3 TCD540s all with lifetime and all with larger hard drives.
I havent bothered hacking them due to it needing the prom mod.

I have an HD TV (no HD satatelite yet, getting in a few weeks) and am ok with the lower quality picture. I had a thought that if Tivo supports recording at 720x480 resolution (from what I have read from other threads), wouldnt setting my tivos to record at this resolution improve my picture quality slightly on the HD TV (since dvds are 720x480p and they look a lot better than best quality from the unhacked Tivo).

So here's the question:
I have an old 1400060 and wanted to practice the prom mod and once hacked using tivoweb, set the default resolutions to be 720by480. I have access to a prom programmer and also to a rework station and successfully installed a socket and changed the appropriate bytes in the prom to disable the security checks (or so I think). I would have thought that after adding the appropriate telnet info to the tivo startup script, I would be able to replace the hard drive, boot up and access bash via telnet (either serial or network). But alas it didnt work.

My quick question is.. is hacking the prom all that is required. Should I be able to get bash now?
thanks in advance, hopefulboydy

[hopefulboydy]

Addition:

Another reason I asked my question above is that I have read contradicting info on what the prom mod actually gets you. Some info has said that it means you dont have to do anything else, some info says you also need to mod the kernel with killhdinitrd, other also say you need the BASH_ENV hack. It would be good is someone who has done a prom mod on a 140, could set me straight. Thanks. If I need to kill the initrd also, I tried that and it looks like my existing kernel isnt compatible with killhdintrd and the only virgin kernel I can find is the 3.1.5 which I dont think works with the 140.

[Jamie]

Addition:

Another reason I asked my question above is that I have read contradicting info on what the prom mod actually gets you. Some info has said that it means you dont have to do anything else, some info says you also need to mod the kernel with killhdinitrd, other also say you need the BASH_ENV hack. It would be good is someone who has done a prom mod on a 140, could set me straight. Thanks. If I need to kill the initrd also, I tried that and it looks like my existing kernel isnt compatible with killhdintrd and the only virgin kernel I can find is the 3.1.5 which I dont think works with the 140.A PROM mod allows you to boot a kernel that doesn't have a valid signature. So, for example, you can modify a stock tivo kernel package with killinitrd or replace_initrd (invalidating the signature), and it will still boot on a PROM mod'd box.

killhdinitrd allows you to nullify the initrd (and the corresponding security checks) without invalidating the signature. So you can boot on a box that doesn't have a prom mod. It only works on Series 2 hardware (not Series 2.5) and only with certain kernel vmlinux.px packages. There is a 7.2.2 kernel compatible with killhdinitrd that works on 140 models. You can get the kernel on the $5 PTVUpgrade lba48 iso "with enhancements".

It's worth reading up on the "chain of trust". Searching for this phrase should yield some good reading.

[cheer]

killhdinitrd allows you to nullify the initrd (and the corresponding security checks) without invalidating the signature. So you can boot on a box that doesn't have a prom mod. It only works on Series 2 hardware (not Series 2.5 or the HDTivo)
Not so -- a killhdinitrd'd 3.1.5 kernel works marvelously on the HDTivo.

[Jamie]

Not so -- a killhdinitrd'd 3.1.5 kernel works marvelously on the HDTivo.Corrected. Think I'm beginning to lose it...

[hopefulboydy]

Thanks. Now it makes sense.
I have searched but cant seem to find a link to killinitrd or replace_initrd.
Any idea where I might get my hads on either of these?

[Jamie]

replace_initrd (http://www.dealdatabase.com/forum/showthread.php?p=91200#post91200)
killinitrd (http://tivoutils.sourceforge.net/)

When the site search doesn't work for you, try google :D

[ocntscha]

So, for example, you can modify a stock tivo kernel package with killinitrd or replace_initrd (invalidating the signature), and it will still boot on a PROM mod'd box.
Is there still a place left in the world for killinitrd now that we have replace_initrd? From what I understand killinitrd will attempt to nullify the security checks on all kernels but its a hit and miss proposition whereas replace_initrd is pretty much guaranteed to always be able to nullify all kernels?

[Jamie]

Is there still a place left in the world for killinitrd now that we have replace_initrd? From what I understand killinitrd will attempt to nullify the security checks on all kernels but its a hit and miss proposition whereas replace_initrd is pretty much guaranteed to always be able to nullify all kernels?Probably not, since no one is porting it to new kernels.

I should also mention that with a PROM mod you can boot custom kernels.

[hopefulboydy]

thanks for all the info.
I will give this a go tonight.
Will probably have to use killinitrd as I dont have access to the replace_initrd binary and would be lost when attempting to compiler the source.
thanks again.

[Jamie]

thanks for all the info.
I will give this a go tonight.
Will probably have to use killinitrd as I dont have access to the replace_initrd binary and would be lost when attempting to compiler the source.
thanks again.What tivo software version are you using? I'm guessing killinitrd isn't going to support any recent kernel you want to use.

[PlainBill]

Corrected. Think I'm beginning to lose it...
You've been working too hard. Take a week off, go fishing, get drunk, enjoy your family (choose all that appeal to you).

PlainBill

[Jamie]

You've been working too hard. Take a week off, go fishing, get drunk, enjoy your family (choose all that appeal to you).Hey, I just got back from a two week vacation. Maybe it's atrophy.

[cheer]

Hey, I just got back from a two week vacation. Maybe it's atrophy.
Don't you have to, like, win a race or something to get one of those?

[hopefulboydy]

jamie,

from memory, I think it is 4.01b as its been boxed up for a while.

[PlainBill]

Don't you have to, like, win a race or something to get one of those?
Nah, you can get atrophy just by watching television. One hour of American Idol will knock 10 points off your IQ.

PlainBill

[hopefulboydy]

Originally Posted by cheer
Don't you have to, like, win a race or something to get one of those?

Well except when you are a kid, as these days, you seem to get atrophy just for taking part.