Ssheven: A modern SSH client for Mac OS 7-9 • Hacker News Board

Re: Ssheven: A modern SSH client for Mac OS 7-9

#21

Post by Gibbon1 » Sat, Jul 31, 2021, 10:55 PM UTC

tambourine_man wrote: post #15

>input latency feels high because redrawing the screen is slow (along with all the encryption, which is also slow) Is modern encryption a challenge to those old machines? Is it because of specialized encryption hardware or sheer brute force? Or is it just this implementation that's slow? I used telnet back in the 68k days.

> Is modern encryption a challenge to those old machines?

I've used modern encryption/mac routines on small embedded micro's and they seem reasonably efficient. Couple of operations per byte. They have to be fast because they are used for decrypting stuff like streaming video. I think an exception is password hashing algorithms which are slow by design.

That said some of the older algorithms are really inefficient. Hundreds of ops per byte.

Re: Ssheven: A modern SSH client for Mac OS 7-9

#22

Post by _qbjt » Sat, Jul 31, 2021, 10:56 PM UTC

Oh wow, thank you for this. :) I was just restoring an iMac G3, the Flower Power edition, and ran into more trouble than I expected trying to transfer data via a USB flash drive. Filesystems that Mac OS 9 should support were either not mounting properly or causing errors during file transfer when formatted on a modern Apple or Linux system (exFAT was the only one I could get to work for some reason). I’ve been casually looking around for some sort of NAS solution that would be compatible with older versions of Mac OS, but with native scp I can just download files from a Linux box (perhaps a dedicated Raspberry Pi) and skip right to the fun part: exploring all of the weird, cool and charming software and games from this era. So cool!

Re: Ssheven: A modern SSH client for Mac OS 7-9

#23

Post by cmiller1 » Sat, Jul 31, 2021, 11:19 PM UTC

This is perfect! Just replaced the battery in my SE/30 and will have to try this as soon as I find an ethernet solution. There are PDS ethernet cards but they're rare and expensive, or SCSI-ethernet adaptors but they're slow.

Re: Ssheven: A modern SSH client for Mac OS 7-9

#24

Post by johnklos » Sat, Jul 31, 2021, 11:22 PM UTC

tambourine_man wrote: post #15

>input latency feels high because redrawing the screen is slow (along with all the encryption, which is also slow) Is modern encryption a challenge to those old machines? Is it because of specialized encryption hardware or sheer brute force? Or is it just this implementation that's slow? I used telnet back in the 68k days.

For reference, using modern ssh to connect to a 15 MHz m68030 Mac LC II with 16 bit memory bus takes literally just under ten minutes (NetBSD 9 to NetBSD 9). An LC III+ with 33 MHz, 32 bit bus m68030 takes a little over 3 minutes.

Re: Ssheven: A modern SSH client for Mac OS 7-9

#25

Post by blibble » Sat, Jul 31, 2021, 11:23 PM UTC

_xy8h wrote: post #17

tambourine_man wrote: post #15

>input latency feels high because redrawing the screen is slow (along with all the encryption, which is also slow) Is modern encryption a challenge to those old machines? Is it because of specialized encryption hardware or sheer brute force? Or is it just this implementation that's slow? I used telnet back in the 68k days.

> Is modern encryption a challenge to those old machines? Ooooooh yeah. It's got some serious overhead on single core systems several-hundred-megahertz systems without the instructions that are used to accelerate encryption these days. AES is what modern CPUs use to help with that. It wasn't until Power7+ before encryption was accelerated on that class of CPUs. The latest Mac to use Power CPUs was discontinued 6 year…

not sure that's right...

for interactive use, compared to rendering to the display and pushing the packet out the crypto overhead is going to be minuscule

Re: Ssheven: A modern SSH client for Mac OS 7-9

#26

Post by retrac » Sat, Jul 31, 2021, 11:34 PM UTC

blibble wrote: post #25

_xy8h wrote: post #17

Earlier quoted context omitted.

> Is modern encryption a challenge to those old machines? Ooooooh yeah. It's got some serious overhead on single core systems several-hundred-megahertz systems without the instructions that are used to accelerate encryption these days. AES is what modern CPUs use to help with that. It wasn't until Power7+ before encryption was accelerated on that class of CPUs. The latest Mac to use Power CPUs was discontinued 6 year…

not sure that's right... for interactive use, compared to rendering to the display and pushing the packet out the crypto overhead is going to be minuscule

Once you have authenticated each other and agree to a nice symmetric cipher and exchange the keys for that, yes. Bytes, even kilobytes per second. But note the "once you have authenticated". Public key crypto is brutal number crunching and takes minutes to hours on systems of the 80s, and some noticeable seconds even in the late 90s. I think that's why something like RSA-4096 was not just universally adopted 30 years ago. It was too expensive to compute for casual use.

Re: Ssheven: A modern SSH client for Mac OS 7-9

#27

Post by Lammy » Sat, Jul 31, 2021, 11:36 PM UTC

_qbjt wrote: post #22

Oh wow, thank you for this. :) I was just restoring an iMac G3, the Flower Power edition, and ran into more trouble than I expected trying to transfer data via a USB flash drive. Filesystems that Mac OS 9 should support were either not mounting properly or causing errors during file transfer when formatted on a modern Apple or Linux system (exFAT was the only one I could get to work for some reason). I’ve been casual…

> some sort of NAS solution that would be compatible with older versions of Mac OS

http://netatalk.sourceforge.net/ :)

Re: Ssheven: A modern SSH client for Mac OS 7-9

#28

Post by slavapestov » Sat, Jul 31, 2021, 11:38 PM UTC

bibinou wrote: post #16

the machine it's probably tested on: http://www.cy384.com/projects/centris-650.html

And it’s sitting on top of a VAX. Perfect pairing

Re: Ssheven: A modern SSH client for Mac OS 7-9

#29

Post by phendrenad2 » Sat, Jul 31, 2021, 11:47 PM UTC

tambourine_man wrote: post #15

>input latency feels high because redrawing the screen is slow (along with all the encryption, which is also slow) Is modern encryption a challenge to those old machines? Is it because of specialized encryption hardware or sheer brute force? Or is it just this implementation that's slow? I used telnet back in the 68k days.

Why is redrawing the screen slow? Old Macs had pretty good DMA for 2D sprites IIRC.

As for encryption, can you use a preshared key instead of public key?

Re: Ssheven: A modern SSH client for Mac OS 7-9

#30

Post by tikwidd » Sat, Jul 31, 2021, 11:49 PM UTC

_qbjt wrote: post #22

Oh wow, thank you for this. :) I was just restoring an iMac G3, the Flower Power edition, and ran into more trouble than I expected trying to transfer data via a USB flash drive. Filesystems that Mac OS 9 should support were either not mounting properly or causing errors during file transfer when formatted on a modern Apple or Linux system (exFAT was the only one I could get to work for some reason). I’ve been casual…

For classic macs with ethernet ports, the simplest method I have found is to host a basic FTP server on another computer (e.g. you can set one up easily enough on a Raspberry Pi) and use an Ftp client such as Fetch on the mac side. I use this method to get files to and from my LC III, which also functions as a bridge baby to the really old macs via the Appletalk serial port.