Command Combination

Conversion of number system in Linux shell

Using double brackets with echo, print, printf

To Decimal

echo $((2#00000001)) = 1
echo $((16#AB)) = 171
echo $((8#70) = 56
print $((8#70))
printf “%d\n” $((8#70)). %d = decimal

Using obase,ibase and bc

Character in hex must be uppercase
echo “obase=10; ibase=16; AB” | bc
echo “obase=2; ibase=16; F” | bc

===========================================================================================================

Compare files

Comm

comm file1 file2
- First column: Line not present in file1
- Second column: line not present in file2
- Third column: file present in both

Diff

diff file1 file2 [-u | -c]: unified or context format
- -: line appears in first file only
- +: line appears in second file only

Some Options

-y: compare side by side

Vimdiff

open multiple files in multiple vim windows
do: gets changes from the other window into the current one
dp: puts the changes from the current window into the other one
]c: jumps to the next change
[c: jumps to the previous change
C w: switches to the other split window.

===========================================================================================================

Combination usage of sed, awk, cut, paste, cat, echo, grep

Combine each 2nd line to the line before it

Original data

#cat 7003.txt | grep -A1 "up" | grep -v "\-\-"
GigabitEthernet0/0/0 is up, line protocol is up
  Internet protocol processing disabled
GigabitEthernet0/0/0.55 is up, line protocol is up
  Internet address is 10.10.10.10/30
GigabitEthernet0/0/0.56 is up, line protocol is up
  Internet address is 10.11.10.10/30
GigabitEthernet0/0/1 is up, line protocol is up
  Internet protocol processing disabled
GigabitEthernet0/0/1.1 is up, line protocol is up
  Internet address is 10.12.10.1/21
GigabitEthernet0/0/1.22 is up, line protocol is up
  Internet address is 10.13.10.1/24
GigabitEthernet0/0/1.23 is up, line protocol is up
  Internet address is 10.14.10.1/24
GigabitEthernet0/0/1.100 is up, line protocol is up
  Internet address is 10.15.10.1/24
Loopback0 is up, line protocol is up
  Internet address is 10.16.10.1/30

Using AWK

#  cat 7003.txt | grep -A1 "up" | grep -v "\-\-" | awk 'NR%2{printf "%s ",$0;next;}1'
GigabitEthernet0/0/0 is up, line protocol is up   Internet protocol processing disabled
GigabitEthernet0/0/0.55 is up, line protocol is up   Internet address is 10.10.10.10/30
GigabitEthernet0/0/0.56 is up, line protocol is up   Internet address is 110.11.10.10/30
GigabitEthernet0/0/1 is up, line protocol is up   Internet protocol processing disabled
GigabitEthernet0/0/1.1 is up, line protocol is up   Internet address is 10.12.10.1/21
GigabitEthernet0/0/1.22 is up, line protocol is up   Internet address is 10.13.10.1/24
GigabitEthernet0/0/1.23 is up, line protocol is up   Internet address is 10.14.10.1/24
GigabitEthernet0/0/1.100 is up, line protocol is up   Internet address is 10.15.10.1/24
Loopback0 is up, line protocol is up   Internet address is 10.16.10.1/30

Using Sed

#cat 7003.txt | grep -A1 "up" | grep -v "\-\-" | sed 'N;s/\n/ /'
GigabitEthernet0/0/0 is up, line protocol is up   Internet protocol processing disabled
GigabitEthernet0/0/0.55 is up, line protocol is up   Internet address is 10.10.10.10/30
GigabitEthernet0/0/0.56 is up, line protocol is up   Internet address is 110.11.10.10/30
GigabitEthernet0/0/1 is up, line protocol is up   Internet protocol processing disabled
GigabitEthernet0/0/1.1 is up, line protocol is up   Internet address is 10.12.10.1/21
GigabitEthernet0/0/1.22 is up, line protocol is up   Internet address is 10.13.10.1/24
GigabitEthernet0/0/1.23 is up, line protocol is up   Internet address is 10.14.10.1/24
GigabitEthernet0/0/1.100 is up, line protocol is up   Internet address is 10.15.10.1/24
Loopback0 is up, line protocol is up   Internet address is 10.16.10.1/30

Using Paste

#  cat 7003.txt | grep -A1 "up" | grep -v "\-\-" | paste -d " " - -
GigabitEthernet0/0/0 is up, line protocol is up   Internet protocol processing disabled
GigabitEthernet0/0/0.55 is up, line protocol is up   Internet address is 10.10.10.10/30
GigabitEthernet0/0/0.56 is up, line protocol is up   Internet address is 110.11.10.10/30
GigabitEthernet0/0/1 is up, line protocol is up   Internet protocol processing disabled
GigabitEthernet0/0/1.1 is up, line protocol is up   Internet address is 10.12.10.1/21
GigabitEthernet0/0/1.22 is up, line protocol is up   Internet address is 10.13.10.1/24
GigabitEthernet0/0/1.23 is up, line protocol is up   Internet address is 10.14.10.1/24
GigabitEthernet0/0/1.100 is up, line protocol is up   Internet address is 10.15.10.1/24
Loopback0 is up, line protocol is up   Internet address is 10.16.10.1/30

Extract 1 line and all indented lines below it

Original data

Standard IP access list 1
    10 permit 211.81.116.123
    20 permit 211.81.116.68, wildcard bits 0.0.3.19 (19476 matches)
    30 permit 211.81.116.136, wildcard bits 0.0.3.19 (2 matches)
    40 permit 211.81.116.152, wildcard bits 0.0.0.3
    50 permit 211.81.122.68, wildcard bits 0.0.0.19
    60 permit 211.81.125.40, wildcard bits 0.0.0.7
    70 permit 211.81.126.60, wildcard bits 0.0.0.3
    80 permit 211.81.126.64, wildcard bits 0.0.0.7
    90 permit 120.150.5.164, wildcard bits 0.0.0.3
    100 permit 120.150.5.144, wildcard bits 0.0.0.15
    110 permit 120.150.5.140, wildcard bits 0.0.0.3
    120 permit 120.150.11.188, wildcard bits 0.0.0.1
Standard IP access list 2
    10 permit 192.143.9.1
    20 permit 192.168.4.20 (30019196 matches)
    30 permit 192.148.9.13
    40 permit 192.168.4.16, wildcard bits 0.0.0.15 (939568 matches)
    50 permit 192.143.0.0, wildcard bits 0.0.0.255
Extended IP access list Anti-Spoofing
    10 deny ip 192.150.8.0 0.0.7.255 any
    20 deny ip 192.150.16.0 0.0.7.255 any
    30 deny ip 192.150.24.0 0.0.7.255 any
    40 permit ip any any (969054186 matches)
Extended IP access list InboundTraffic
    10 permit ip 100.65.0.0 0.31.255.255 any
    20 permit ip 100.50.0.0 0.0.255.255 any
    30 permit ip any 192.143.244.0 0.0.0.255
    40 permit ip 192.148.0.0 0.1.255.255 192.150.16.0 0.0.15.255
    50 permit ip 192.143.0.0 0.0.127.255 192.150.16.0 0.0.15.255
    60 permit ip 192.168.0.0 0.0.63.255 192.150.16.0 0.0.15.255
    70 permit ip 192.143.234.0 0.0.0.255 192.150.16.0 0.0.15.255
    80 permit ip 10.6.0.0 0.0.255.255 192.150.16.0 0.0.15.255
    90 permit ip 192.17.96.0 0.0.7.255 192.150.16.0 0.0.15.255
    100 permit ip 10.32.96.0 0.0.7.255 192.150.16.0 0.0.15.255
    110 permit ip 192.164.64.0 0.0.15.255 192.150.16.0 0.0.15.255
    120 permit ip 192.182.16.0 0.0.15.255 192.150.16.0 0.0.15.255
    130 permit ip 192.123.24.0 0.0.7.255 192.150.16.0 0.0.15.255
    140 permit ip 192.123.160.0 0.0.7.255 192.150.16.0 0.0.15.255
    150 permit ip 192.124.64.0 0.0.7.255 192.150.16.0 0.0.15.255
    160 permit ip host 203.46.212.155 192.150.16.0 0.0.15.255
    170 permit tcp any 192.150.16.0 0.0.15.255 eq www 443 3269
    180 permit ip 192.17.7.0 0.0.0.255 192.150.16.0 0.0.15.255
    190 deny ip any any
Extended IP access list OutboundTraffic
    10 permit ip any any log

Using AWK

#cat acl.txt | awk '/InboundTraffic/ && !f{f=1;x=$0;sub(/[^ ].*/,"",x);x=x" ";print;next} f {if (substr($0,1,length(x))==x)print; else f=0}'
Extended IP access list InboundTraffic
    10 permit ip 100.65.0.0 0.31.255.255 any
    20 permit ip 100.50.0.0 0.0.255.255 any
    30 permit ip any 192.143.244.0 0.0.0.255
    40 permit ip 192.148.0.0 0.1.255.255 192.150.16.0 0.0.15.255
    50 permit ip 192.143.0.0 0.0.127.255 192.150.16.0 0.0.15.255
    60 permit ip 192.168.0.0 0.0.63.255 192.150.16.0 0.0.15.255
    70 permit ip 192.143.234.0 0.0.0.255 192.150.16.0 0.0.15.255
    80 permit ip 10.6.0.0 0.0.255.255 192.150.16.0 0.0.15.255
    90 permit ip 192.17.96.0 0.0.7.255 192.150.16.0 0.0.15.255
    100 permit ip 10.32.96.0 0.0.7.255 192.150.16.0 0.0.15.255
    110 permit ip 192.164.64.0 0.0.15.255 192.150.16.0 0.0.15.255
    120 permit ip 192.182.16.0 0.0.15.255 192.150.16.0 0.0.15.255
    130 permit ip 192.123.24.0 0.0.7.255 192.150.16.0 0.0.15.255
    140 permit ip 192.123.160.0 0.0.7.255 192.150.16.0 0.0.15.255
    150 permit ip 192.124.64.0 0.0.7.255 192.150.16.0 0.0.15.255
    160 permit ip host 203.46.212.155 192.150.16.0 0.0.15.255
    170 permit tcp any 192.150.16.0 0.0.15.255 eq www 443 3269
    180 permit ip 192.17.7.0 0.0.0.255 192.150.16.0 0.0.15.255
    190 deny ip any any

Print range of character from each line

cut -c 1-N

Check IP address of domain and print out domain, ip address or domain, not found

while read -r domain; do ip=$(host "$domain" | awk '/has address/ {print $4}'); echo "$domain,${ip:-not found}"; done < domains.txt

===========================================================================================================

Testing SMTP, SMTPS, HTTP, HTTPS using CLI commands

SMTP

telnet smtp.gmail.com 25
Trying 74.125.68.109...
Connected to smtp.gmail.com.
Escape character is '^]'.
220 smtp.gmail.com ESMTP m6sm1314984pfc.133 - gsmtp

SMTPS

Using SSL

openssl s_client -connect smtp.gmail.com:465
CONNECTED(00000003)
depth=2 OU = GlobalSign Root CA - R2, O = GlobalSign, CN = GlobalSign
verify return:1
depth=1 C = US, O = Google Trust Services, CN = GTS CA 1O1
verify return:1
depth=0 C = US, ST = California, L = Mountain View, O = Google LLC, CN = smtp.gmail.com
verify return:1
---
Certificate chain
 0 s:C = US, ST = California, L = Mountain View, O = Google LLC, CN = smtp.gmail.com
   i:C = US, O = Google Trust Services, CN = GTS CA 1O1
 1 s:C = US, O = Google Trust Services, CN = GTS CA 1O1
   i:OU = GlobalSign Root CA - R2, O = GlobalSign, CN = GlobalSign
---
Server certificate
-----BEGIN CERTIFICATE-----
MIIExjCCA66gAwIBAgIQVkWCHiVGZO8DAAAAAMv3iDANBgkqhkiG9w0BAQsFADBC
...<omitted>
MwPSLvh2HjaIF7pQ49VSqgSjKEp26EWNP+4GKVUdPGObFxC/PmXjQrWKVfWnegqt
VrtCxAkMXdLFaiIK8pxlTZUIk1yYSJUSfbw=
-----END CERTIFICATE-----
subject=C = US, ST = California, L = Mountain View, O = Google LLC, CN = smtp.gmail.com

issuer=C = US, O = Google Trust Services, CN = GTS CA 1O1

---
No client certificate CA names sent
Peer signing digest: SHA256
Peer signature type: ECDSA
Server Temp Key: X25519, 253 bits
---
SSL handshake has read 2639 bytes and written 386 bytes
Verification: OK
---
New, TLSv1.3, Cipher is TLS_AES_256_GCM_SHA384
Server public key is 256 bit
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
Early data was not sent
Verify return code: 0 (ok)
---
---
Post-Handshake New Session Ticket arrived:
...<omitted>
---
read R BLOCK
220 smtp.gmail.com ESMTP gb9sm9409673pjb.7 - gsmtp

Using TLS

openssl s_client -starttls smtp -connect smtp.gmail.com:587
CONNECTED(00000005)
depth=2 OU = GlobalSign Root CA - R2, O = GlobalSign, CN = GlobalSign
verify return:1
depth=1 C = US, O = Google Trust Services, CN = GTS CA 1O1
verify return:1
depth=0 C = US, ST = California, L = Mountain View, O = Google LLC, CN = smtp.gmail.com
verify return:1
---
Certificate chain
 0 s:/C=US/ST=California/L=Mountain View/O=Google LLC/CN=smtp.gmail.com
   i:/C=US/O=Google Trust Services/CN=GTS CA 1O1
 1 s:/C=US/O=Google Trust Services/CN=GTS CA 1O1
   i:/OU=GlobalSign Root CA - R2/O=GlobalSign/CN=GlobalSign
---
Server certificate
-----BEGIN CERTIFICATE-----
MIIExjCCA66gAwIBAgIQVkWCHiVGZO8DAAAAAMv3iDANBgkqhkiG9w0BAQsFADBC
...<omitted>...
VrtCxAkMXdLFaiIK8pxlTZUIk1yYSJUSfbw=
-----END CERTIFICATE-----
subject=/C=US/ST=California/L=Mountain View/O=Google LLC/CN=smtp.gmail.com
issuer=/C=US/O=Google Trust Services/CN=GTS CA 1O1
---
No client certificate CA names sent
Server Temp Key: ECDH, X25519, 253 bits
---
SSL handshake has read 3071 bytes and written 316 bytes
---
New, TLSv1/SSLv3, Cipher is ECDHE-ECDSA-CHACHA20-POLY1305
Server public key is 256 bit
Secure Renegotiation IS supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
SSL-Session:
    Protocol  : TLSv1.2
    Cipher    : ECDHE-ECDSA-CHACHA20-POLY1305
    Session-ID: 025EACDB2907E4B3A6A8281757E8D26267B94046042B86A0393692DAB4771D45
    Session-ID-ctx:
    Master-Key: 8F34FE9B422432F74BD062C7FD7D03B7A52A07682D50AF313CD7D5931900D30757E198C89B5E4DF3B4C813B00248C8EB
    TLS session ticket lifetime hint: 100800 (seconds)
    TLS session ticket:
    0000 - 01 db 8c 82 9a 73 82 f7-cd d0 21 06 99 ce 19 c6   .....s....!.....
    ...<omitted>...

    Start Time: 1621007660
    Timeout   : 7200 (sec)
    Verify return code: 0 (ok)
---
250 SMTPUTF8
ehlo gmail.com
250-smtp.gmail.com at your service
250-SIZE 35882577
250-8BITMIME
250-AUTH LOGIN PLAIN XOAUTH2 PLAIN-CLIENTTOKEN OAUTHBEARER XOAUTH
250-ENHANCEDSTATUSCODES
250-PIPELINING
250-CHUNKING
250 SMTPUTF8

other utilities
- telnet-ssl: apt install telnet-ssl
- gnutls-cli: apt install gnutls-cli

HTTP

telnet google.com 80
Trying 142.250.70.174...
Connected to google.com.
Escape character is '^]'.
GET / HTTP/1.1
Host: google.com (double enter)

HTTP/1.1 301 Moved Permanently
Location: http://www.google.com/
Content-Type: text/html; charset=UTF-8
Date: Fri, 14 May 2021 14:06:08 GMT
Expires: Sun, 13 Jun 2021 14:06:08 GMT
Cache-Control: public, max-age=2592000
Server: gws
Content-Length: 219
X-XSS-Protection: 0
X-Frame-Options: SAMEORIGIN

<HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8">
<TITLE>301 Moved</TITLE></HEAD><BODY>
<H1>301 Moved</H1>
The document has moved
<A HREF="http://www.google.com/">here</A>.
</BODY></HTML>

HTTPS

openssl s_client -connect google.com:443
CONNECTED(00000003)
depth=2 OU = GlobalSign Root CA - R2, O = GlobalSign, CN = GlobalSign
verify return:1
depth=1 C = US, O = Google Trust Services, CN = GTS CA 1O1
verify return:1
depth=0 C = US, ST = California, L = Mountain View, O = Google LLC, CN = *.google.com
verify return:1
---
Certificate chain
 0 s:C = US, ST = California, L = Mountain View, O = Google LLC, CN = *.google.com
   i:C = US, O = Google Trust Services, CN = GTS CA 1O1
 1 s:C = US, O = Google Trust Services, CN = GTS CA 1O1
   i:OU = GlobalSign Root CA - R2, O = GlobalSign, CN = GlobalSign
---
Server certificate
-----BEGIN CERTIFICATE-----
MIIJmzCCCIOgAwIBAgIQFovg59On54cDAAAAAMv3WTANBgkqhkiG9w0BAQsFADBC
...<omitted>...
cbEvNDP+IehoDZ3hA96l
-----END CERTIFICATE-----
subject=C = US, ST = California, L = Mountain View, O = Google LLC, CN = *.google.com

issuer=C = US, O = Google Trust Services, CN = GTS CA 1O1

---
No client certificate CA names sent
Peer signing digest: SHA256
Peer signature type: ECDSA
Server Temp Key: X25519, 253 bits
---
SSL handshake has read 3876 bytes and written 382 bytes
Verification: OK
---
New, TLSv1.3, Cipher is TLS_AES_256_GCM_SHA384
Server public key is 256 bit
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
No ALPN negotiated
Early data was not sent
Verify return code: 0 (ok)
---
GET / HTTP/1.1
Host: google.com (double enter)

---
Post-Handshake New Session Ticket arrived:
SSL-Session:
    Protocol  : TLSv1.3
    Cipher    : TLS_AES_256_GCM_SHA384
    Session-ID: 4F40524A688468CCC1BFBA740619DDFF4D1867E67954B77FA4737D1451F060DD
    Session-ID-ctx:
    Resumption PSK: DDDC4DBCB2C07AD961498E0E5C22A41140448F2A50B3533ED48BD09B5FF01DAAA0D481594D176E41743EDAB9437A3C0A
    PSK identity: None
    PSK identity hint: None
    SRP username: None
    TLS session ticket lifetime hint: 172800 (seconds)
    TLS session ticket:
    0000 - 01 69 63 1e 13 63 37 c4-1c d9 35 e4 17 8e df e6   .ic..c7...5.....
    ...<omitted>...
    00e0 - 00 d0 1a f5 f5 f3 e6 30-b4 09 55 2f               .......0..U/

    Start Time: 1621001254
    Timeout   : 7200 (sec)
    Verify return code: 0 (ok)
    Extended master secret: no
    Max Early Data: 0
---
read R BLOCK
---
Post-Handshake New Session Ticket arrived:
SSL-Session:
    ...<omitted>...
---
read R BLOCK
HTTP/1.1 301 Moved Permanently
Location: https://www.google.com/
Content-Type: text/html; charset=UTF-8
Date: Fri, 14 May 2021 14:07:34 GMT
Expires: Sun, 13 Jun 2021 14:07:34 GMT
Cache-Control: public, max-age=2592000
Server: gws
Content-Length: 220
X-XSS-Protection: 0
X-Frame-Options: SAMEORIGIN
Alt-Svc: h3-29=":443"; ma=2592000,h3-T051=":443"; ma=2592000,h3-Q050=":443"; ma=2592000,h3-Q046=":443"; ma=2592000,h3-Q043=":443"; ma=2592000,quic=":443"; ma=2592000; v="46,43"

<HTML><HEAD><meta http-equiv="content-type" content="text/html;charset=utf-8">
<TITLE>301 Moved</TITLE></HEAD><BODY>
<H1>301 Moved</H1>
The document has moved
<A HREF="https://www.google.com/">here</A>.
</BODY></HTML>

Reference

https://unix.stackexchange.com/questions/184340/how-to-grep-a-line-with-unknown-number-of-its-indented-lines
https://qmail.jms1.net/test-auth.shtml
https://www.samlogic.net/articles/smtp-commands-reference-auth.htm
https://www.ndchost.com/wiki/mail/test-smtp-auth-telnet

PreviousC NextFind

Last updated 10 months ago

hashtagConversion of number system in Linux shell

hashtagUsing double brackets with echo, print, printf

hashtagUsing obase,ibase and bc

hashtagCompare files

hashtagComm

hashtagDiff

hashtagSome Options

hashtagVimdiff

hashtagCombination usage of sed, awk, cut, paste, cat, echo, grep

hashtagCombine each 2nd line to the line before it

hashtagOriginal data

hashtagUsing AWK

hashtagUsing Sed

hashtagUsing Paste

hashtagExtract 1 line and all indented lines below it

hashtagOriginal data

hashtagUsing AWK

hashtagPrint range of character from each line

hashtagCheck IP address of domain and print out domain, ip address or domain, not found

hashtagTesting SMTP, SMTPS, HTTP, HTTPS using CLI commands

hashtagSMTP

hashtagSMTPS

hashtagUsing SSL

hashtagUsing TLS

hashtagHTTP

hashtagHTTPS

hashtagReference

Conversion of number system in Linux shell

Using double brackets with echo, print, printf

Using obase,ibase and bc

Compare files

Comm

Diff

Some Options

Vimdiff

Combination usage of sed, awk, cut, paste, cat, echo, grep

Combine each 2nd line to the line before it

Original data

Using AWK

Using Sed

Using Paste

Extract 1 line and all indented lines below it

Original data

Using AWK

Print range of character from each line

Check IP address of domain and print out domain, ip address or domain, not found

Testing SMTP, SMTPS, HTTP, HTTPS using CLI commands

SMTP

SMTPS

Using SSL

Using TLS

HTTP

HTTPS

Reference