4 ms·

because in those days there was no curl, or wget. and then when there was, there was no guarantee they'd be installed. telnet was always there though. it also

by a-dub 4mo ago

because in those days there was no curl, or wget. and then when there was, there was no guarantee they'd be installed. telnet was always there though. it also worked for speaking all the other plaintext internet protocols. (imap, pop, smtp, etc)

dragontamer 4mo ago
Note: Telnet is not completely plaintext and has control characters in the upper byte range (like 0xff or something, I forget). Use nc or this TCP Bash technique if you really want to ensure decent compatibility when doing hacky solutions, otherwise a random 0xFF somewhere from a terminal console color change (or other control character) might really screw you over. EDIT or ya know, use the correct tool like Curl.
HeckFeck 4mo ago
I used telnet to send mail via SMTP once, it's quite literally a good social protocol because it begins with a polite 'HELO'.
- a-dub 4mo ago
  the '90s version of finding the hiring manager or boss on linkedin to try and get a job was connecting to the company's public smtp server with telnet, using their name to probe different email address patterns with "rcpt to:" (those days the actual servers were often directly connected to the internet and would leak email address validity in how they would respond to rcpt to) and then sending them a nice email. smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO.
  - endofreach 4mo ago
    > smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO. email will become so unusable, next one will have to be HELNO i guess
  - jolmg 4mo ago
    > smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO. "EHLO" still sounds friendly. It just sounds like a different accent or something. Know someone that used to answer calls with a friendly "Jello?".
    - a-dub 4mo ago
      yeah, i think you're right. i originally read a bit of snarky blow-off, like "eh?" ... but you know, now that i think of it, it's actually does have more of a friendly canadian style vibe.
    - xp84 4mo ago
      Eventually Microsoft will debut Microsoft Extended SMTP which will greet with MEHLO
- nativeit 4mo ago
  Is it the reply to ‘HELO’ that enables things like tarpits? Like if my server replied with ‘HI PLEASURE TO MEET YOU 127.0.0.1 THAT NAME SOUNDS FAMILIAR ARE YOU BY CHANCE FROM BOSTON MY MOTHER IS FROM BOSTON WELL QUINCY ACTUALLY BUT DO YOU KNOW 127.0.1.1 THEY ARE A REALLY GOOD FRIEND OF MINE YOU SHOULD MEET I HEAR THEIR DAUGHTER IS A DOCTOR DONTYAKNOW AND YOU COULD…” etc, etc?
  - edoceo 4mo ago
    For SMTP tarpits you can do all kinds of fun stuff. Not just in the reply to helo. Like: always be slow to respond. Respond to each command with a temporary error. Accept everything, then pause, then error. Send back large chunks of garbage.
hadlock 4mo ago
In the days of ultra thin containers, there's still no guarantee curl or wget will be installed, either.

by a-dub 4mo ago

dragontamer 4mo ago

Note: Telnet is not completely plaintext and has control characters in the upper byte range (like 0xff or something, I forget). Use nc or this TCP Bash technique if you really want to ensure decent compatibility when doing hacky solutions, otherwise a random 0xFF somewhere from a terminal console color change (or other control character) might really screw you over. EDIT or ya know, use the correct tool like Curl.

HeckFeck 4mo ago

I used telnet to send mail via SMTP once, it's quite literally a good social protocol because it begins with a polite 'HELO'.

a-dub 4mo ago
the '90s version of finding the hiring manager or boss on linkedin to try and get a job was connecting to the company's public smtp server with telnet, using their name to probe different email address patterns with "rcpt to:" (those days the actual servers were often directly connected to the internet and would leak email address validity in how they would respond to rcpt to) and then sending them a nice email. smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO.
- endofreach 4mo ago
  > smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO. email will become so unusable, next one will have to be HELNO i guess
- jolmg 4mo ago
  > smtp grew up to be an antisocial curmudgeon. extended smtp starts with EHLO. "EHLO" still sounds friendly. It just sounds like a different accent or something. Know someone that used to answer calls with a friendly "Jello?".
  - a-dub 4mo ago
    yeah, i think you're right. i originally read a bit of snarky blow-off, like "eh?" ... but you know, now that i think of it, it's actually does have more of a friendly canadian style vibe.
  - xp84 4mo ago
    Eventually Microsoft will debut Microsoft Extended SMTP which will greet with MEHLO
nativeit 4mo ago
Is it the reply to ‘HELO’ that enables things like tarpits? Like if my server replied with ‘HI PLEASURE TO MEET YOU 127.0.0.1 THAT NAME SOUNDS FAMILIAR ARE YOU BY CHANCE FROM BOSTON MY MOTHER IS FROM BOSTON WELL QUINCY ACTUALLY BUT DO YOU KNOW 127.0.1.1 THEY ARE A REALLY GOOD FRIEND OF MINE YOU SHOULD MEET I HEAR THEIR DAUGHTER IS A DOCTOR DONTYAKNOW AND YOU COULD…” etc, etc?
- edoceo 4mo ago
  For SMTP tarpits you can do all kinds of fun stuff. Not just in the reply to helo. Like: always be slow to respond. Respond to each command with a temporary error. Accept everything, then pause, then error. Send back large chunks of garbage.

hadlock 4mo ago

In the days of ultra thin containers, there's still no guarantee curl or wget will be installed, either.