blog.area23.at: März 2024

2024-03-28

system library:BIO_connect:Connection refused:../crypto/bio/bio_sock2.c

I got the strange error message

system library:BIO_connect:Connection refused:../crypto/bio/bio_sock2.c

on executing

openssl s_client -starttls smtp -connect mail.area23.at:587

when testing sendmail smtp tls with an Let's Encrypt SSL certificate.

If you got the same error message, ensure that

sendmail is running (on mail server / relay host)
test it with init rc script
/etc/init.d/sendmail status
or simple by process listing tools, like
pstree | grep sendmaail
pidof sendmail-mta
ps fauxwww | grep sendmail
and network server socket is bound
netstat -avn 2>&1 |less
or fuser and your sendmail port
fuser -v -n tcp 25
or various variants of lsof, like
lsof -i TCP:25
sendmail is well configured (on mail server / relay host)
this will take a little bit too long for that article
in my case it was a wrong IPv6 address in sendmail.mc
DAEMON_OPTIONS(`Family=inet6, Name=MTA-v6, Port=smtp, Addr=2600:1f14:1d6d:f202:8d53:fc57:c45d:6590')dnl
mail server is reachable from outside
test it with
telnet [mailserver] [port]
or brutal way with a network scanner, like nmap
nmap -p 25,465,587 [mailserver]

if mailserver is not reachable from outside,
then you must lookup on server and on client firewall rules, e.g.
iptables -t filter --list
iptables -6 -t filter --list

You could also simply run strace to see, what happens:
strace openssl s_client -starttls smtp -connect mail.area23.at:587

strace openssl s_client -starttls smtp -connect [mailserver] [port]

2024-03-12

par coole trendy Firmen aus Deutschland

bereits top (vielleicht sogar etwas over the top):

Chal-Tec GmbH

Wallstraße 16, 10179 Berlin, Deutschland
https://maps.app.goo.gl/fVUmk6XMwx7ko2Fc9

#Sound #Light
https://www.elektronik-star.de/Sound-Light/

#MultiMedia #Audio

https://www.elektronik-star.de/Multimedia-Audio/

Kessler Electronic

Dieselstraße 4, 50170 Kerpen, Deutschland

https://maps.app.goo.gl/vCG6S8hoSCTC9FPF9

#Brücken #Gleichrichter
https://www.kessler-electronic.de/de/Bauelemente/Halbleiter-diskret/Brucken-Gleichrichter

#Halbleiter #integriert
https://www.kessler-electronic.de/de/Bauelemente/Halbleiter-integriert
wie z.B. A/D-Wandler 8-Bit 4 µs DIP24

#Mobile #Energie
https://www.kessler-electronic.de/de/Strom/Mobile-Energie

#Powerbanks und Zusatz-Akkus
https://www.kessler-electronic.de/de/Tab-Phone/Powerbanks-und-Zusatz-Akkus

2024-03-07

html uft-8 symbol generation shell script

I wrote tonight a short uft-8 html escapes generating shell script,
see script generated results here: https://area23.at/utf8/.

#!/bin/sh
# generates uft-8 symbol html reference

outtext=utf8_pre_sym2000.html

modHex=256
modFF=255
modZero=0
shx=1024

printf "<html>\n<head><title>utf-8 symbol></title></head>\n<body>\n\t<h1>UTF-8 Symbols</h1>\n\t<div><span>\n" > $outtext

while [ $shx -lt 16384 ] ; do

        modZero=$(echo "$shx % $modHex" | bc)
        if [ $modZero -eq 0 ] ; then
                printf "\n<h2>hex x%x ~ dec %d</h2>\n" $shx $shx >> $outtext
                printf "\n<pre>symbol\thex x%x \tdecimal %d \t.\n" $shx $shx >> $outtext
        fi

        printf "&#x%x;\t&#x%x;\t&#%d;\t.\n" $shx $shx $shx  >> $outtext

        modFF=$(echo "$shx % $modHex" | bc)
        if [ $modFF -eq 255 ] ; then
                printf "</pre>\n" >> $outtext
        fi

    shx=$(echo "$shx + 1" | bc);
done

printf "\n\t<hr />\n\t</span></div></body></html>\n" >> $outtext

see full script at pastebin.com/0aNumds1

https://pastebin.com/0aNumds1

blog.darkstar.work - a simple url encoder/decoder

Labels

2024-03-29

UTF-8 unicode cool symbol work already in many cases

2024-03-28

system library:BIO_connect:Connection refused:../crypto/bio/bio_sock2.c

2024-03-12

par coole trendy Firmen aus Deutschland

Chal-Tec GmbH

Kessler Electronic

reichelt elektronik GmbH

k-electronic GmbH

2024-03-07

html uft-8 symbol generation shell script