From bc2c09139b8d689da9077f4d588f81c19a5185e5 Mon Sep 17 00:00:00 2001 From: Jacob Kraniak <113630934+jacob-kraniak@users.noreply.github.com> Date: Sat, 7 Mar 2026 18:18:31 -0500 Subject: [PATCH] split readme at line 1430 : 2026-03-07 18:18:31 Affected files: .obsidian/workspace.json README.md documentation/learning-resources/daily-knowledge-news.md documentation/manuals-howtos-guides/shell-one-liners.md documentation/manuals-howtos-guides/shell-tricks-functions.md documentation/other-cheat-sheets.md documentation/readme - to refactor.md --- .obsidian/workspace.json | 34 +- README.md | 2853 +---------------- .../daily-knowledge-news.md | 0 .../manuals-howtos-guides/shell-one-liners.md | 0 .../shell-tricks-functions.md | 0 documentation/other-cheat-sheets.md | 0 documentation/readme - to refactor.md | 2849 ++++++++++++++++ 7 files changed, 2868 insertions(+), 2868 deletions(-) rename {tools/cross-domain => documentation}/learning-resources/daily-knowledge-news.md (100%) rename tools/cross-domain/manuals-howtos-tutorials.md => documentation/manuals-howtos-guides/shell-one-liners.md (100%) rename tools/cross-domain/other-cheat-sheets.md => documentation/manuals-howtos-guides/shell-tricks-functions.md (100%) create mode 100644 documentation/other-cheat-sheets.md create mode 100644 documentation/readme - to refactor.md diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json index 6e19b0f..78412a9 100644 --- a/.obsidian/workspace.json +++ b/.obsidian/workspace.json @@ -13,12 +13,12 @@ "state": { "type": "markdown", "state": { - "file": "tools/sysadmin-devops/terminal-shell-productivity/Terminal Emulators.md", + "file": "README.md", "mode": "source", "source": true }, "icon": "lucide-file", - "title": "Terminal Emulators" + "title": "README" } } ] @@ -94,7 +94,7 @@ "state": { "type": "backlink", "state": { - "file": "tools/sysadmin-devops/terminal-shell-productivity/Terminal Emulators.md", + "file": "README.md", "collapseAll": false, "extraContext": false, "sortOrder": "alphabetical", @@ -104,7 +104,7 @@ "unlinkedCollapsed": true }, "icon": "links-coming-in", - "title": "Backlinks for Terminal Emulators" + "title": "Backlinks for README" } }, { @@ -113,12 +113,12 @@ "state": { "type": "outgoing-link", "state": { - "file": "tools/sysadmin-devops/terminal-shell-productivity/Terminal Emulators.md", + "file": "README.md", "linksCollapsed": false, "unlinkedCollapsed": true }, "icon": "links-going-out", - "title": "Outgoing links from Terminal Emulators" + "title": "Outgoing links from README" } }, { @@ -156,13 +156,13 @@ "state": { "type": "outline", "state": { - "file": "tools/sysadmin-devops/terminal-shell-productivity/Terminal Emulators.md", + "file": "README.md", "followCursor": false, "showSearch": false, "searchQuery": "" }, "icon": "lucide-list", - "title": "Outline of Terminal Emulators" + "title": "Outline of README" } }, { @@ -196,7 +196,15 @@ }, "active": "4ec77f521918a14f", "lastOpenFiles": [ + "documentation/readme - to refactor.md", "README.md", + "documentation/manuals-howtos-guides/shell-tricks-functions.md", + "documentation/other-cheat-sheets.md", + "documentation/manuals-howtos-guides/shell-one-liners.md", + "documentation/manuals-howtos-guides", + "documentation/learning-resources/daily-knowledge-news.md", + "tools/sysadmin-devops/terminal-shell-productivity/Terminal Emulators.md", + "documentation", "docs/sysadmin-devops/terminal-shell-productivity/shell-functions.md", "docs/sysadmin-devops/terminal-shell-productivity/shell-one-liners.md", "tools/system-services.md", @@ -212,25 +220,17 @@ "tools/security/pentest-recon-enum/Port Scanners & Network Discovery.md", "tools/security/pentest-recon-enum/Recon & Threat Reputation.md", "tools/sysadmin-devops/system-monitoring-tracing/Log Analyzers.md", - "tools/sysadmin-devops/terminal-shell-productivity/Terminal Emulators.md", "tools/sysadmin-devops/Remote Access + SSH Clients.md", "docs/sysadmin-devops/ssh-remote-access", "tools/network-engineering/diagnostics-troubleshooting/Online Network Diagnostics & Utilities.md", "tools/network-engineering/routing-bgp-ospf/BGP & Routing Tools.md", "tools/network-engineering/diagnostics-troubleshooting/Global Internet Measurement Platform.md", "tools/network-engineering/diagnostics-troubleshooting", - "tools/cross-domain/manuals-howtos-tutorials.md", - "tools/cross-domain/learning-resources/daily-knowledge-news.md", "TOOL-TABLE-SCHEMA.md", "Contibuting.md", - "tools/my-contributions.md", "tools/sysadmin-devops/system-monitoring-tracing", - "tools/00_index.md", - "tools/tools - (migrate out)/cli-tools.md", "tools/network-engineering/routing-bgp-ospf", "tools/network-engineering/dns-dhc-ipam", - "tools/network-engineering", - "tools/cross-domain", - "tools/sysadmin-devops/diagnostics-troubleshooting" + "tools/network-engineering" ] } \ No newline at end of file diff --git a/README.md b/README.md index 997ecfd..f92fb8f 100644 --- a/README.md +++ b/README.md @@ -74,7 +74,7 @@ A forked collection of inspiring lists, manuals, cheatsheets, blogs, hacks, one- - [Systems/Services](./docs/systems-services.md) - [Networks](./docs/networks.md) - [Containers/Orchestration](./docs/containers-orchestration.md) -- [Manuals/Howtos/Tutorials](manuals-howtos-tutorials.md) +- [Manuals/Howtos/Tutorials](shell-one-liners.md) - [Inspiring Lists](./docs/inspiring-lists.md) - [Blogs/Podcasts/Videos](./docs/blogs-podcasts-videos.md) - [Hacking/Penetration Testing](./docs/hacking-penetration-testing.md) @@ -1428,2853 +1428,4 @@ AWS deployment tool.
   x86 Bare Metal Examples - dozens of minimal operating systems to learn x86 system programming.
   simple-computer - the scott CPU from "But How Do It Know?" by J. Clark Scott.
   littleosbook - the little book about OS development.
-

- -###### DNS Servers list (privacy) - -| IP | URL | -| :--- | :--- | -| **`84.200.69.80`** | [dns.watch](https://dns.watch/) | -| **`94.247.43.254`** | [opennic.org](https://www.opennic.org/) | -| **`64.6.64.6`** | [verisign.com](https://www.verisign.com/en_US/security-services/public-dns/index.xhtml) | -| **`89.233.43.71`** | [censurfridns.dk](https://blog.uncensoreddns.org/) | -| **`1.1.1.1`** | [cloudflare.com](https://1.1.1.1/) | -###### TOP Browser extensions - -| Extension name | Description | -| :--- | :--- | -| **`IPvFoo`** | Display the server IP address and HTTPS information across all page elements. | -| **`FoxyProxy`** | Simplifies configuring browsers to access proxy-servers. | -| **`HTTPS Everywhere`** | Automatically use HTTPS security on many sites. | -| **`uMatrix`** | Point & click to forbid/allow any class of requests made by your browser. | -| **`uBlock Origin`** | An efficient blocker: easy on memory and CPU footprint. | -| **`Session Buddy`** | Manage browser tabs and bookmarks with ease. | -| **`SuperSorter`** | Sort bookmarks recursively, delete duplicates, merge folders, and more. | -| **`Clear Cache`** | Clear your cache and browsing data. | -| **`d3coder`** | Encoding/Decoding plugin for various types of encoding. | -| **`Web Developer`** | Adds a toolbar button with various web developer tools. | -| **`ThreatPinch Lookup`** | Add threat intelligence hover tool tips. | - -###### TOP Burp extensions - -| Extension name | Description | -| :--- | :--- | -| **`Active Scan++`** | Extends Burp's active and passive scanning capabilities. | -| **`Autorize`** | Automatically detects authorization enforcement. | -| **`AuthMatrix`** | A simple matrix grid to define the desired levels of access privilege. | -| **`Logger++`** | Logs requests and responses for all Burp tools in a sortable table. | -| **`Bypass WAF`** | Adds headers useful for bypassing some WAF devices. | -| **`JSON Beautifier`** | Beautifies JSON content in the HTTP message viewer. | -| **`JSON Web Tokens`** | Enables Burp to decode and manipulate JSON web tokens. | -| **`CSP Auditor`** | Displays CSP headers for responses, and passively reports CSP weaknesses. | -| **`CSP-Bypass`** | Passively scans for CSP headers that contain known bypasses. | -| **`Hackvertor`** | Converts data using a tag-based configuration to apply various encoding. | -| **`HTML5 Auditor`** | Scans for usage of risky HTML5 features. | -| **`Software Vulnerability Scanner`** | Vulnerability scanner based on vulners.com audit API. | -| **`Turbo Intruder`** | Is a powerful bruteforcing tool. | -| **`Upload Scanner`** | Upload a number of different file types, laced with different forms of payload. | - -###### Hack Mozilla Firefox address bar - -In Firefox's address bar, you can limit results by typing special characters before or after your term: - -- `^` - for matches in your browsing history -- `*` - for matches in your bookmarks. -- `%` - for matches in your currently open tabs. -- `#` - for matches in page titles. -- `@` - for matches in web addresses. - -###### Chrome hidden commands - -- `chrome://chrome-urls` - list of all commands -- `chrome://flags` - enable experiments and development features -- `chrome://interstitials` - errors and warnings -- `chrome://net-internals` - network internals (events, dns, cache) -- `chrome://network-errors` - network errors -- `chrome://net-export` - start logging future network activity to a file -- `chrome://safe-browsing` - safe browsing options -- `chrome://user-actions` - record all user actions -- `chrome://restart` - restart chrome -- `chrome://dino` - ERR_INTERNET_DISCONNECTED... -- `cache:` - view the cached version of the web page - -###### Bypass WAFs by Shortening IP Address (by [0xInfection](https://x.com/0xInfection)) - -IP addresses can be shortened by dropping the zeroes: - -``` -http://1.0.0.1 → http://1.1 -http://127.0.0.1 → http://127.1 -http://192.168.0.1 → http://192.168.1 - -http://0xC0A80001 or http://3232235521 → 192.168.0.1 -http://192.168.257 → 192.168.1.1 -http://192.168.516 → 192.168.2.4 -``` - - > This bypasses WAF filters for SSRF, open-redirect, etc where any IP as input gets blacklisted. - -###### Hashing, encryption and encoding (by [Michal Špaček](https://twitter.com/spazef0rze)) - -_Hashing_ - -plaintext :arrow_right: hash
-hash :no_entry: plaintext - -_Symmetric encryption_ - -plaintext :arrow_right: :key: :arrow_right: ciphertext
-plaintext :arrow_left: :key: :arrow_left: ciphertext
-(:key: shared key) - -_Asymmetric encryption_ - -plaintext :arrow_right: :key: :arrow_right: ciphertext
-plaintext :arrow_left: :part_alternation_mark: :arrow_left: ciphertext
-(:key: public key, :part_alternation_mark: private key)
- -_Encoding_ - -text :arrow_right: encoded
-text :arrow_left: encoded - -#### Shell One-liners  [[TOC]](#anger-table-of-contents) - -##### Table of Contents - - * [terminal](#tool-terminal) - * [busybox](#tool-busybox) - * [mount](#tool-mount) - * [fuser](#tool-fuser) - * [lsof](#tool-lsof) - * [ps](#tool-ps) - * [top](#tool-top) - * [vmstat](#tool-vmstat) - * [iostat](#tool-iostat) - * [strace](#tool-strace) - * [kill](#tool-kill) - * [find](#tool-find) - * [diff](#tool-diff) - * [vimdiff](#tool-vimdiff) - * [tail](#tool-tail) - * [cpulimit](#tool-cpulimit) - * [pwdx](#tool-pwdx) - * [tr](#tool-tr) - * [chmod](#tool-chmod) - * [who](#tool-who) - * [last](#tool-last) - * [screen](#tool-screen) - * [script](#tool-script) - * [du](#tool-du) - * [inotifywait](#tool-inotifywait) - * [openssl](#tool-openssl) - * [secure-delete](#tool-secure-delete) - * [dd](#tool-dd) - * [gpg](#tool-gpg) - * [system-other](#tool-system-other) - * [curl](#tool-curl) - * [httpie](#tool-httpie) - * [ssh](#tool-ssh) - * [linux-dev](#tool-linux-dev) - * [tcpdump](#tool-tcpdump) - * [tcpick](#tool-tcpick) - * [ngrep](#tool-ngrep) - * [hping3](#tool-hping3) - * [nmap](#tool-nmap) - * [netcat](#tool-netcat) - * [socat](#tool-socat) - * [p0f](#tool-p0f) - * [gnutls-cli](#tool-gnutls-cli) - * [netstat](#tool-netstat) - * [rsync](#tool-rsync) - * [host](#tool-host) - * [dig](#tool-dig) - * [certbot](#tool-certbot) - * [network-other](#tool-network-other) - * [git](#tool-git) - * [awk](#tool-awk) - * [sed](#tool-sed) - * [grep](#tool-grep) - * [perl](#tool-perl) - -##### Tool: [terminal](https://en.wikipedia.org/wiki/Linux_console) - -###### Reload shell without exit - -```bash -exec $SHELL -l -``` - -###### Close shell keeping all subprocess running - -```bash -disown -a && exit -``` - -###### Exit without saving shell history - -```bash -kill -9 $$ -unset HISTFILE && exit -``` - -###### Perform a branching conditional - -```bash -true && echo success -false || echo failed -``` - -###### Pipe stdout and stderr to separate commands - -```bash -some_command > >(/bin/cmd_for_stdout) 2> >(/bin/cmd_for_stderr) -``` - -###### Redirect stdout and stderr each to separate files and print both to the screen - -```bash -(some_command 2>&1 1>&3 | tee errorlog ) 3>&1 1>&2 | tee stdoutlog -``` - -###### List of commands you use most often - -```bash -history | \ -awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | \ -grep -v "./" | \ -column -c3 -s " " -t | \ -sort -nr | nl | head -n 20 -``` - -###### Sterilize bash history - -```bash -function sterile() { - - history | awk '$2 != "history" { $1=""; print $0 }' | egrep -vi "\ -curl\b+.*(-E|--cert)\b+.*\b*|\ -curl\b+.*--pass\b+.*\b*|\ -curl\b+.*(-U|--proxy-user).*:.*\b*|\ -curl\b+.*(-u|--user).*:.*\b* -.*(-H|--header).*(token|auth.*)\b+.*|\ -wget\b+.*--.*password\b+.*\b*|\ -http.?://.+:.+@.*\ -" > $HOME/histbuff; history -r $HOME/histbuff; - -} - -export PROMPT_COMMAND="sterile" -``` - - > Look also: [A naive utility to censor credentials in command history](https://github.com/lbonanomi/go/blob/master/revisionist.go). - -###### Quickly backup a file - -```bash -cp filename{,.orig} -``` - -###### Empty a file (truncate to 0 size) - -```bash ->filename -``` - -###### Delete all files in a folder that don't match a certain file extension - -```bash -rm !(*.foo|*.bar|*.baz) -``` - -###### Pass multi-line string to a file - -```bash -# cat >filename ... - overwrite the file -# cat >>filename ... - append to a file -cat > filename << __EOF__ -data data data -__EOF__ -``` - -###### Edit a file on a remote host using vim - -```bash -vim scp://user@host//etc/fstab -``` - -###### Create a directory and change into it at the same time - -```bash -mkd() { mkdir -p "$@" && cd "$@"; } -``` - -###### Convert uppercase files to lowercase files - -```bash -rename 'y/A-Z/a-z/' * -``` - -###### Print a row of characters across the terminal - -```bash -printf "%`tput cols`s" | tr ' ' '#' -``` - -###### Show shell history without line numbers - -```bash -history | cut -c 8- -fc -l -n 1 | sed 's/^\s*//' -``` - -###### Run command(s) after exit session - -```bash -cat > /etc/profile << __EOF__ -_after_logout() { - - username=$(whoami) - - for _pid in $(ps afx | grep sshd | grep "$username" | awk '{print $1}') ; do - - kill -9 $_pid - - done - -} -trap _after_logout EXIT -__EOF__ -``` - -###### Generate a sequence of numbers - -```bash -for ((i=1; i<=10; i+=2)) ; do echo $i ; done -# alternative: seq 1 2 10 - -for ((i=5; i<=10; ++i)) ; do printf '%02d\n' $i ; done -# alternative: seq -w 5 10 - -for i in {1..10} ; do echo $i ; done -``` - -###### Simple Bash filewatching - -```bash -unset MAIL; export MAILCHECK=1; export MAILPATH='$FILE_TO_WATCH?$MESSAGE' -``` - ---- - -##### Tool: [busybox](https://www.busybox.net/) - -###### Static HTTP web server - -```bash -busybox httpd -p $PORT -h $HOME [-c httpd.conf] -``` - -___ - -##### Tool: [mount](https://en.wikipedia.org/wiki/Mount_(Unix)) - -###### Mount a temporary ram partition - -```bash -mount -t tmpfs tmpfs /mnt -o size=64M -``` - - * `-t` - filesystem type - * `-o` - mount options - -###### Remount a filesystem as read/write - -```bash -mount -o remount,rw / -``` - -___ - -##### Tool: [fuser](https://en.wikipedia.org/wiki/Fuser_(Unix)) - -###### Show which processes use the files/directories - -```bash -fuser /var/log/daemon.log -fuser -v /home/supervisor -``` - -###### Kills a process that is locking a file - -```bash -fuser -ki filename -``` - - * `-i` - interactive option - -###### Kills a process that is locking a file with specific signal - -```bash -fuser -k -HUP filename -``` - - * `--list-signals` - list available signal names - -###### Show what PID is listening on specific port - -```bash -fuser -v 53/udp -``` - -###### Show all processes using the named filesystems or block device - -```bash -fuser -mv /var/www -``` - -___ - -##### Tool: [lsof](https://en.wikipedia.org/wiki/Lsof) - -###### Show process that use internet connection at the moment - -```bash -lsof -P -i -n -``` - -###### Show process that use specific port number - -```bash -lsof -i tcp:443 -``` - -###### Lists all listening ports together with the PID of the associated process - -```bash -lsof -Pan -i tcp -i udp -``` - -###### List all open ports and their owning executables - -```bash -lsof -i -P | grep -i "listen" -``` - -###### Show all open ports - -```bash -lsof -Pnl -i -``` - -###### Show open ports (LISTEN) - -```bash -lsof -Pni4 | grep LISTEN | column -t -``` - -###### List all files opened by a particular command - -```bash -lsof -c "process" -``` - -###### View user activity per directory - -```bash -lsof -u username -a +D /etc -``` - -###### Show 10 largest open files - -```bash -lsof / | \ -awk '{ if($7 > 1048576) print $7/1048576 "MB" " " $9 " " $1 }' | \ -sort -n -u | tail | column -t -``` - -###### Show current working directory of a process - -```bash -lsof -p | grep cwd -``` - -___ - -##### Tool: [ps](https://en.wikipedia.org/wiki/Ps_(Unix)) - -###### Show a 4-way scrollable process tree with full details - -```bash -ps awwfux | less -S -``` - -###### Processes per user counter - -```bash -ps hax -o user | sort | uniq -c | sort -r -``` - -###### Show all processes by name with main header - -```bash -ps -lfC nginx -``` - -___ - -##### Tool: [find](https://en.wikipedia.org/wiki/Find_(Unix)) - -###### Find files that have been modified on your system in the past 60 minutes - -```bash -find / -mmin 60 -type f -``` - -###### Find all files larger than 20M - -```bash -find / -type f -size +20M -``` - -###### Find duplicate files (based on MD5 hash) - -```bash -find -type f -exec md5sum '{}' ';' | sort | uniq --all-repeated=separate -w 33 -``` - -###### Change permission only for files - -```bash -cd /var/www/site && find . -type f -exec chmod 766 {} \; -cd /var/www/site && find . -type f -exec chmod 664 {} + -``` - -###### Change permission only for directories - -```bash -cd /var/www/site && find . -type d -exec chmod g+x {} \; -cd /var/www/site && find . -type d -exec chmod g+rwx {} + -``` - -###### Find files and directories for specific user/group - -```bash -# User: -find . -user -print -find /etc -type f -user -name "*.conf" - -# Group: -find /opt -group -find /etc -type f -group -iname "*.conf" -``` - -###### Find files and directories for all without specific user/group - -```bash -# User: -find . \! -user -print - -# Group: -find . \! -group -``` - -###### Looking for files/directories that only have certain permission - -```bash -# User -find . -user -perm -u+rw # -rw-r--r-- -find /home -user $(whoami) -perm 777 # -rwxrwxrwx - -# Group: -find /home -type d -group -perm 755 # -rwxr-xr-x -``` - -###### Delete older files than 60 days - -```bash -find . -type f -mtime +60 -delete -``` - -###### Recursively remove all empty sub-directories from a directory - -```bash -find . -depth -type d -empty -exec rmdir {} \; -``` - -###### How to find all hard links to a file - -```bash -find -xdev -samefile filename -``` - -###### Recursively find the latest modified files - -```bash -find . -type f -exec stat --format '%Y :%y %n' "{}" \; | sort -nr | cut -d: -f2- | head -``` - -###### Recursively find/replace of a string with sed - -```bash -find . -not -path '*/\.git*' -type f -print0 | xargs -0 sed -i 's/foo/bar/g' -``` - -###### Recursively find/replace of a string in directories and file names - -```bash -find . -depth -name '*test*' -execdir bash -c 'mv -v "$1" "${1//foo/bar}"' _ {} \; -``` - -###### Recursively find suid executables - -```bash -find / \( -perm -4000 -o -perm -2000 \) -type f -exec ls -la {} \; -``` - -___ - -##### Tool: [top](https://en.wikipedia.org/wiki/Top_(software)) - -###### Use top to monitor only all processes with the specific string - -```bash -top -p $(pgrep -d , ) -``` - - * `` - process containing string (eg. nginx, worker) - -___ - -##### Tool: [vmstat](https://en.wikipedia.org/wiki/Vmstat) - -###### Show current system utilization (fields in kilobytes) - -```bash -vmstat 2 20 -t -w -``` - - * `2` - number of times with a defined time interval (delay) - * `20` - each execution of the command (count) - * `-t` - show timestamp - * `-w` - wide output - * `-S M` - output of the fields in megabytes instead of kilobytes - -###### Show current system utilization will get refreshed every 5 seconds - -```bash -vmstat 5 -w -``` - -###### Display report a summary of disk operations - -```bash -vmstat -D -``` - -###### Display report of event counters and memory stats - -```bash -vmstat -s -``` - -###### Display report about kernel objects stored in slab layer cache - -```bash -vmstat -m -``` - -##### Tool: [iostat](https://en.wikipedia.org/wiki/Iostat) - -###### Show information about the CPU usage, and I/O statistics about all the partitions - -```bash -iostat 2 10 -t -m -``` - - * `2` - number of times with a defined time interval (delay) - * `10` - each execution of the command (count) - * `-t` - show timestamp - * `-m` - fields in megabytes (`-k` - in kilobytes, default) - -###### Show information only about the CPU utilization - -```bash -iostat 2 10 -t -m -c -``` - -###### Show information only about the disk utilization - -```bash -iostat 2 10 -t -m -d -``` - -###### Show information only about the LVM utilization - -```bash -iostat -N -``` - -___ - -##### Tool: [strace](https://en.wikipedia.org/wiki/Strace) - -###### Track with child processes - -```bash -# 1) -strace -f -p $(pidof glusterfsd) - -# 2) -strace -f $(pidof php-fpm | sed 's/\([0-9]*\)/\-p \1/g') -``` - -###### Track process with 30 seconds limit - -```bash -timeout 30 strace $(< /var/run/zabbix/zabbix_agentd.pid) -``` - -###### Track processes and redirect output to a file - -```bash -ps auxw | grep '[a]pache' | awk '{print " -p " $2}' | \ -xargs strace -o /tmp/strace-apache-proc.out -``` - -###### Track with print time spent in each syscall and limit length of print strings - -```bash -ps auxw | grep '[i]init_policy' | awk '{print " -p " $2}' | \ -xargs strace -f -e trace=network -T -s 10000 -``` - -###### Track the open request of a network port - -```bash -strace -f -e trace=bind nc -l 80 -``` - -###### Track the open request of a network port (show TCP/UDP) - -```bash -strace -f -e trace=network nc -lu 80 -``` - -___ - -##### Tool: [kill](https://en.wikipedia.org/wiki/Kill_(command)) - -###### Kill a process running on port - -```bash -kill -9 $(lsof -i : | awk '{l=$2} END {print l}') -``` - -___ - -##### Tool: [diff](https://en.wikipedia.org/wiki/Diff) - -###### Compare two directory trees - -```bash -diff <(cd directory1 && find | sort) <(cd directory2 && find | sort) -``` - -###### Compare output of two commands - -```bash -diff <(cat /etc/passwd) <(cut -f2 /etc/passwd) -``` - -___ - -##### Tool: [vimdiff](https://git-scm.com/docs/vimdiff) - -###### Highlight the exact differences, based on characters and words - -```bash -vimdiff file1 file2 -``` - -###### Compare two JSON files - -```bash -vimdiff <(jq -S . A.json) <(jq -S . B.json) -``` - -###### Compare Hex dump - -```bash -d(){ vimdiff <(f $1) <(f $2);};f(){ hexdump -C $1 | cut -d' ' -f3- | tr -s ' ';}; d ~/bin1 ~/bin2 -``` - -###### diffchar - -Save [diffchar](https://raw.githubusercontent.com/vim-scripts/diffchar.vim/master/plugin/diffchar.vim) @ `~/.vim/plugins` - -Click `F7` to switch between diff modes - -Usefull `vimdiff` commands: - -* `qa` to exit all windows -* `:vertical resize 70` to resize window -* set window width `Ctrl+W [N columns]+(Shift+)<\>` - -___ - -##### Tool: [tail](https://en.wikipedia.org/wiki/Tail_(Unix)) - -###### Annotate tail -f with timestamps - -```bash -tail -f file | while read ; do echo "$(date +%T.%N) $REPLY" ; done -``` - -###### Analyse an Apache access log for the most common IP addresses - -```bash -tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail -``` - -###### Analyse web server log and show only 5xx http codes - -```bash -tail -n 100 -f /path/to/logfile | grep "HTTP/[1-2].[0-1]\" [5]" -``` - -___ - -##### Tool: [tar](https://en.wikipedia.org/wiki/Tar_(computing)) - -###### System backup with exclude specific directories - -```bash -cd / -tar -czvpf /mnt/system$(date +%d%m%Y%s).tgz --directory=/ \ ---exclude=proc/* --exclude=sys/* --exclude=dev/* --exclude=mnt/* . -``` - -###### System backup with exclude specific directories (pigz) - -```bash -cd / -tar cvpf /backup/snapshot-$(date +%d%m%Y%s).tgz --directory=/ \ ---exclude=proc/* --exclude=sys/* --exclude=dev/* \ ---exclude=mnt/* --exclude=tmp/* --use-compress-program=pigz . -``` - -___ - -##### Tool: [dump](https://en.wikipedia.org/wiki/Dump_(program)) - -###### System backup to file - -```bash -dump -y -u -f /backup/system$(date +%d%m%Y%s).lzo / -``` - -###### Restore system from lzo file - -```bash -cd / -restore -rf /backup/system$(date +%d%m%Y%s).lzo -``` - -___ - -##### Tool: [tr](https://en.wikipedia.org/wiki/Tr_(Unix)) - -###### Show directories in the PATH, one per line - -```bash -tr : '\n' <<<$PATH -``` - -___ - -##### Tool: [chmod](https://en.wikipedia.org/wiki/Chmod) - -###### Remove executable bit from all files in the current directory - -```bash -chmod -R -x+X * -``` - -###### Restore permission for /bin/chmod - -```bash -# 1: -cp /bin/ls chmod.01 -cp /bin/chmod chmod.01 -./chmod.01 700 file - -# 2: -/bin/busybox chmod 0700 /bin/chmod - -# 3: -setfacl --set u::rwx,g::---,o::--- /bin/chmod -``` - -___ - -##### Tool: [who](https://en.wikipedia.org/wiki/Who_(Unix)) - -###### Find last reboot time - -```bash -who -b -``` - -###### Detect a user sudo-su'd into the current shell - -```bash -[[ $(who -m | awk '{ print $1 }') == $(whoami) ]] || echo "You are su-ed to $(whoami)" -``` - -___ - -##### Tool: [last](https://www.howtoforge.com/linux-last-command/) - -###### Was the last reboot a panic? - -```bash -(last -x -f $(ls -1t /var/log/wtmp* | head -2 | tail -1); last -x -f /var/log/wtmp) | \ -grep -A1 reboot | head -2 | grep -q shutdown && echo "Expected reboot" || echo "Panic reboot" -``` - -___ - -##### Tool: [screen](https://en.wikipedia.org/wiki/GNU_Screen) - -###### Start screen in detached mode - -```bash -screen -d -m -``` - -###### Attach to an existing screen session - -```bash -screen -r -d -``` - -___ - -##### Tool: [script](https://en.wikipedia.org/wiki/Script_(Unix)) - -###### Record and replay terminal session - -```bash -### Record session -# 1) -script -t 2>~/session.time -a ~/session.log - -# 2) -script --timing=session.time session.log - -### Replay session -scriptreplay --timing=session.time session.log -``` - -___ - -##### Tool: [du](https://en.wikipedia.org/wiki/GNU_Screen) - -###### Show 20 biggest directories with 'K M G' - -```bash -du | \ -sort -r -n | \ -awk '{split("K M G",v); s=1; while($1>1024){$1/=1024; s++} print int($1)" "v[s]"\t"$2}' | \ -head -n 20 -``` - -___ - -##### Tool: [inotifywait](https://en.wikipedia.org/wiki/GNU_Screen) - -###### Init tool everytime a file in a directory is modified - -```bash -while true ; do inotifywait -r -e MODIFY dir/ && ls dir/ ; done; -``` - -___ - -##### Tool: [openssl](https://www.openssl.org/) - -###### Testing connection to the remote host - -```bash -echo | openssl s_client -connect google.com:443 -showcerts -``` - -###### Testing connection to the remote host (debug mode) - -```bash -echo | openssl s_client -connect google.com:443 -showcerts -tlsextdebug -status -``` - -###### Testing connection to the remote host (with SNI support) - -```bash -echo | openssl s_client -showcerts -servername google.com -connect google.com:443 -``` - -###### Testing connection to the remote host with specific ssl version - -```bash -openssl s_client -tls1_2 -connect google.com:443 -``` - -###### Testing connection to the remote host with specific ssl cipher - -```bash -openssl s_client -cipher 'AES128-SHA' -connect google.com:443 -``` - -###### Verify 0-RTT - -```bash -_host="example.com" - -cat > req.in << __EOF__ -HEAD / HTTP/1.1 -Host: $_host -Connection: close -__EOF__ - -openssl s_client -connect ${_host}:443 -tls1_3 -sess_out session.pem -ign_eof < req.in -openssl s_client -connect ${_host}:443 -tls1_3 -sess_in session.pem -early_data req.in -``` - -###### Generate private key without passphrase - -```bash -# _len: 2048, 4096 -( _fd="private.key" ; _len="2048" ; \ -openssl genrsa -out ${_fd} ${_len} ) -``` - -###### Generate private key with passphrase - -```bash -# _ciph: aes128, aes256 -# _len: 2048, 4096 -( _ciph="aes128" ; _fd="private.key" ; _len="2048" ; \ -openssl genrsa -${_ciph} -out ${_fd} ${_len} ) -``` - -###### Remove passphrase from private key - -```bash -( _fd="private.key" ; _fd_unp="private_unp.key" ; \ -openssl rsa -in ${_fd} -out ${_fd_unp} ) -``` - -###### Encrypt existing private key with a passphrase - -```bash -# _ciph: aes128, aes256 -( _ciph="aes128" ; _fd="private.key" ; _fd_pass="private_pass.key" ; \ -openssl rsa -${_ciph} -in ${_fd} -out ${_fd_pass} -``` - -###### Check private key - -```bash -( _fd="private.key" ; \ -openssl rsa -check -in ${_fd} ) -``` - -###### Get public key from private key - -```bash -( _fd="private.key" ; _fd_pub="public.key" ; \ -openssl rsa -pubout -in ${_fd} -out ${_fd_pub} ) -``` - -###### Generate private key and CSR - -```bash -( _fd="private.key" ; _fd_csr="request.csr" ; _len="2048" ; \ -openssl req -out ${_fd_csr} -new -newkey rsa:${_len} -nodes -keyout ${_fd} ) -``` - -###### Generate CSR - -```bash -( _fd="private.key" ; _fd_csr="request.csr" ; \ -openssl req -out ${_fd_csr} -new -key ${_fd} ) -``` - -###### Generate CSR (metadata from existing certificate) - - > Where `private.key` is the existing private key. As you can see you do not generate this CSR from your certificate (public key). Also you do not generate the "same" CSR, just a new one to request a new certificate. - -```bash -( _fd="private.key" ; _fd_csr="request.csr" ; _fd_crt="cert.crt" ; \ -openssl x509 -x509toreq -in ${_fd_crt} -out ${_fd_csr} -signkey ${_fd} ) -``` - -###### Generate CSR with -config param - -```bash -( _fd="private.key" ; _fd_csr="request.csr" ; \ -openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \ --config <( -cat << __EOF__ -[req] -default_bits = 2048 -default_md = sha256 -prompt = no -distinguished_name = dn -req_extensions = req_ext - -[ dn ] -C = "" -ST = "" -L = "" -O = "" -OU = "
" -CN = "" - -[ req_ext ] -subjectAltName = @alt_names - -[ alt_names ] -DNS.1 = -DNS.2 = -DNS.3 = -__EOF__ -)) -``` - -Other values in `[ dn ]`: - -``` -countryName = "DE" # C= -stateOrProvinceName = "Hessen" # ST= -localityName = "Keller" # L= -postalCode = "424242" # L/postalcode= -postalAddress = "Keller" # L/postaladdress= -streetAddress = "Crater 1621" # L/street= -organizationName = "apfelboymschule" # O= -organizationalUnitName = "IT Department" # OU= -commonName = "example.com" # CN= -emailAddress = "webmaster@example.com" # CN/emailAddress= -``` - -Example of `oids` (you'll probably also have to make OpenSSL know about the new fields required for EV by adding the following under `[new_oids]`): - -``` -[req] -... -oid_section = new_oids - -[ new_oids ] -postalCode = 2.5.4.17 -streetAddress = 2.5.4.9 -``` - -Full example: - -```bash -( _fd="private.key" ; _fd_csr="request.csr" ; \ -openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \ --config <( -cat << __EOF__ -[req] -default_bits = 2048 -default_md = sha256 -prompt = no -distinguished_name = dn -req_extensions = req_ext -oid_section = new_oids - -[ new_oids ] -serialNumber = 2.5.4.5 -streetAddress = 2.5.4.9 -postalCode = 2.5.4.17 -businessCategory = 2.5.4.15 - -[ dn ] -serialNumber=00001111 -businessCategory=Private Organization -jurisdictionC=DE -C=DE -ST=Hessen -L=Keller -postalCode=424242 -streetAddress=Crater 1621 -O=AV Company -OU=IT -CN=example.com - -[ req_ext ] -subjectAltName = @alt_names - -[ alt_names ] -DNS.1 = example.com -__EOF__ -)) -``` - -For more information please look at these great explanations: - -- [RFC 5280](https://tools.ietf.org/html/rfc5280) -- [Generate a multi domains certificate using config files](https://gist.github.com/romainnorberg/464758a6620228b977212a3cf20c3e08) -- [Your OpenSSL CSR command is out of date](https://expeditedsecurity.com/blog/openssl-csr-command/) -- [OpenSSL example configuration file](https://www.tbs-certificats.com/openssl-dem-server-cert.cnf) -- [Object Identifiers (OIDs)](https://www.alvestrand.no/objectid/) -- [openssl objects.txt](https://github.com/openssl/openssl/blob/master/crypto/objects/objects.txt) - -###### List available EC curves - -```bash -openssl ecparam -list_curves -``` - -###### Print ECDSA private and public keys - -```bash -( _fd="private.key" ; \ -openssl ec -in ${_fd} -noout -text ) - -# For x25519 only extracting public key -( _fd="private.key" ; _fd_pub="public.key" ; \ -openssl pkey -in ${_fd} -pubout -out ${_fd_pub} ) -``` - -###### Generate ECDSA private key - -```bash -# _curve: prime256v1, secp521r1, secp384r1 -( _fd="private.key" ; _curve="prime256v1" ; \ -openssl ecparam -out ${_fd} -name ${_curve} -genkey ) - -# _curve: X25519 -( _fd="private.key" ; _curve="x25519" ; \ -openssl genpkey -algorithm ${_curve} -out ${_fd} ) -``` - -###### Generate private key and CSR (ECC) - -```bash -# _curve: prime256v1, secp521r1, secp384r1 -( _fd="domain.com.key" ; _fd_csr="domain.com.csr" ; _curve="prime256v1" ; \ -openssl ecparam -out ${_fd} -name ${_curve} -genkey ; \ -openssl req -new -key ${_fd} -out ${_fd_csr} -sha256 ) -``` - -###### Generate self-signed certificate - -```bash -# _len: 2048, 4096 -( _fd="domain.key" ; _fd_out="domain.crt" ; _len="2048" ; _days="365" ; \ -openssl req -newkey rsa:${_len} -nodes \ --keyout ${_fd} -x509 -days ${_days} -out ${_fd_out} ) -``` - -###### Generate self-signed certificate from existing private key - -```bash -# _len: 2048, 4096 -( _fd="domain.key" ; _fd_out="domain.crt" ; _days="365" ; \ -openssl req -key ${_fd} -nodes \ --x509 -days ${_days} -out ${_fd_out} ) -``` - -###### Generate self-signed certificate from existing private key and csr - -```bash -# _len: 2048, 4096 -( _fd="domain.key" ; _fd_csr="domain.csr" ; _fd_out="domain.crt" ; _days="365" ; \ -openssl x509 -signkey ${_fd} -nodes \ --in ${_fd_csr} -req -days ${_days} -out ${_fd_out} ) -``` - -###### Generate DH public parameters - -```bash -( _dh_size="2048" ; \ -openssl dhparam -out /etc/nginx/ssl/dhparam_${_dh_size}.pem "$_dh_size" ) -``` - -###### Display DH public parameters - -```bash -openssl pkeyparam -in dhparam.pem -text -``` - -###### Extract private key from pfx - -```bash -( _fd_pfx="cert.pfx" ; _fd_key="key.pem" ; \ -openssl pkcs12 -in ${_fd_pfx} -nocerts -nodes -out ${_fd_key} ) -``` - -###### Extract private key and certs from pfx - -```bash -( _fd_pfx="cert.pfx" ; _fd_pem="key_certs.pem" ; \ -openssl pkcs12 -in ${_fd_pfx} -nodes -out ${_fd_pem} ) -``` - -###### Extract certs from p7b - -```bash -# PKCS#7 file doesn't include private keys. -( _fd_p7b="cert.p7b" ; _fd_pem="cert.pem" ; \ -openssl pkcs7 -inform DER -outform PEM -in ${_fd_p7b} -print_certs > ${_fd_pem}) -# or: -openssl pkcs7 -print_certs -in -in ${_fd_p7b} -out ${_fd_pem}) -``` - -###### Convert DER to PEM - -```bash -( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \ -openssl x509 -in ${_fd_der} -inform der -outform pem -out ${_fd_pem} ) -``` - -###### Convert PEM to DER - -```bash -( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \ -openssl x509 -in ${_fd_pem} -outform der -out ${_fd_der} ) -``` - -###### Verification of the private key - -```bash -( _fd="private.key" ; \ -openssl rsa -noout -text -in ${_fd} ) -``` - -###### Verification of the public key - -```bash -# 1) -( _fd="public.key" ; \ -openssl pkey -noout -text -pubin -in ${_fd} ) - -# 2) -( _fd="private.key" ; \ -openssl rsa -inform PEM -noout -in ${_fd} &> /dev/null ; \ -if [ $? = 0 ] ; then echo -en "OK\n" ; fi ) -``` - -###### Verification of the certificate - -```bash -( _fd="certificate.crt" ; # format: pem, cer, crt \ -openssl x509 -noout -text -in ${_fd} ) -``` - -###### Verification of the CSR - -```bash -( _fd_csr="request.csr" ; \ -openssl req -text -noout -in ${_fd_csr} ) -``` - -###### Check the private key and the certificate are match - -```bash -(openssl rsa -noout -modulus -in private.key | openssl md5 ; \ -openssl x509 -noout -modulus -in certificate.crt | openssl md5) | uniq -``` - -###### Check the private key and the CSR are match - -```bash -(openssl rsa -noout -modulus -in private.key | openssl md5 ; \ -openssl req -noout -modulus -in request.csr | openssl md5) | uniq -``` - -___ - -##### Tool: [secure-delete](https://wiki.archlinux.org/index.php/Securely_wipe_disk) - -###### Secure delete with shred - -```bash -shred -vfuz -n 10 file -shred --verbose --random-source=/dev/urandom -n 1 /dev/sda -``` - -###### Secure delete with scrub - -```bash -scrub -p dod /dev/sda -scrub -p dod -r file -``` - -###### Secure delete with badblocks - -```bash -badblocks -s -w -t random -v /dev/sda -badblocks -c 10240 -s -w -t random -v /dev/sda -``` - -###### Secure delete with secure-delete - -```bash -srm -vz /tmp/file -sfill -vz /local -sdmem -v -swapoff /dev/sda5 && sswap -vz /dev/sda5 -``` - -___ - -##### Tool: [dd](https://en.wikipedia.org/wiki/Dd_(Unix)) - -###### Show dd status every so often - -```bash -dd status=progress -watch --interval 5 killall -USR1 dd -``` - -###### Redirect output to a file with dd - -```bash -echo "string" | dd of=filename -``` - -___ - -##### Tool: [gpg](https://www.gnupg.org/) - -###### Export public key - -```bash -gpg --export --armor "" > username.pkey -``` - - * `--export` - export all keys from all keyrings or specific key - * `-a|--armor` - create ASCII armored output - -###### Encrypt file - -```bash -gpg -e -r "" dump.sql -``` - - * `-e|--encrypt` - encrypt data - * `-r|--recipient` - encrypt for specific - -###### Decrypt file - -```bash -gpg -o dump.sql -d dump.sql.gpg -``` - - * `-o|--output` - use as output file - * `-d|--decrypt` - decrypt data (default) - -###### Search recipient - -```bash -gpg --keyserver hkp://keyserver.ubuntu.com --search-keys "" -``` - - * `--keyserver` - set specific key server - * `--search-keys` - search for keys on a key server - -###### List all of the packets in an encrypted file - -```bash -gpg --batch --list-packets archive.gpg -gpg2 --batch --list-packets archive.gpg -``` - -___ - -##### Tool: [system-other](https://github.com/trimstray/the-book-of-secret-knowledge#tool-system-other) - -###### Reboot system from init - -```bash -exec /sbin/init 6 -``` - -###### Init system from single user mode - -```bash -exec /sbin/init -``` - -###### Show current working directory of a process - -```bash -readlink -f /proc//cwd -``` - -###### Show actual pathname of the executed command - -```bash -readlink -f /proc//exe -``` - -##### Tool: [curl](https://curl.haxx.se) - -```bash -curl -Iks https://www.google.com -``` - - * `-I` - show response headers only - * `-k` - insecure connection when using ssl - * `-s` - silent mode (not display body) - -```bash -curl -Iks --location -X GET -A "x-agent" https://www.google.com -``` - - * `--location` - follow redirects - * `-X` - set method - * `-A` - set user-agent - -```bash -curl -Iks --location -X GET -A "x-agent" --proxy http://127.0.0.1:16379 https://www.google.com -``` - - * `--proxy [socks5://|http://]` - set proxy server - -```bash -curl -o file.pdf -C - https://example.com/Aiju2goo0Ja2.pdf -``` - - * `-o` - write output to file - * `-C` - resume the transfer - -###### Find your external IP address (external services) - -```bash -curl ipinfo.io -curl ipinfo.io/ip -curl icanhazip.com -curl ifconfig.me/ip ; echo -``` - -###### Repeat URL request - -```bash -# URL sequence substitution with a dummy query string: -curl -ks https://example.com/?[1-20] - -# With shell 'for' loop: -for i in {1..20} ; do curl -ks https://example.com/ ; done -``` - -###### Check DNS and HTTP trace with headers for specific domains - -```bash -### Set domains and external dns servers. -_domain_list=(google.com) ; _dns_list=("8.8.8.8" "1.1.1.1") - -for _domain in "${_domain_list[@]}" ; do - - printf '=%.0s' {1..48} - - echo - - printf "[\\e[1;32m+\\e[m] resolve: %s\\n" "$_domain" - - for _dns in "${_dns_list[@]}" ; do - - # Resolve domain. - host "${_domain}" "${_dns}" - - echo - - done - - for _proto in http https ; do - - printf "[\\e[1;32m+\\e[m] trace + headers: %s://%s\\n" "$_proto" "$_domain" - - # Get trace and http headers. - curl -Iks -A "x-agent" --location "${_proto}://${_domain}" - - echo - - done - -done - -unset _domain_list _dns_list -``` - -___ - -##### Tool: [httpie](https://httpie.org/) - -```bash -http -p Hh https://www.google.com -``` - - * `-p` - print request and response headers - * `H` - request headers - * `B` - request body - * `h` - response headers - * `b` - response body - -```bash -http -p Hh https://www.google.com --follow --verify no -``` - - * `-F, --follow` - follow redirects - * `--verify no` - skip SSL verification - -```bash -http -p Hh https://www.google.com --follow --verify no \ ---proxy http:http://127.0.0.1:16379 -``` - - * `--proxy [http:]` - set proxy server - -##### Tool: [ssh](https://www.openssh.com/) - -###### Escape Sequence - -``` -# Supported escape sequences: -~. - terminate connection (and any multiplexed sessions) -~B - send a BREAK to the remote system -~C - open a command line -~R - Request rekey (SSH protocol 2 only) -~^Z - suspend ssh -~# - list forwarded connections -~& - background ssh (when waiting for connections to terminate) -~? - this message -~~ - send the escape character by typing it twice -``` - -###### Compare a remote file with a local file - -```bash -ssh user@host cat /path/to/remotefile | diff /path/to/localfile - -``` - -###### SSH connection through host in the middle - -```bash -ssh -t reachable_host ssh unreachable_host -``` - -###### Run command over SSH on remote host - -```bash -cat > cmd.txt << __EOF__ -cat /etc/hosts -__EOF__ - -ssh host -l user $(&1 | tee -a "${_sesdir}/$(date +%Y%m%d).log" - -} - -# Alias: -alias ssh='_ssh_sesslog' -``` - -###### Using Keychain for SSH logins - -```bash -### Delete all of ssh-agent's keys. -function _scl() { - - /usr/bin/keychain --clear - -} - -### Add key to keychain. -function _scg() { - - /usr/bin/keychain /path/to/private-key - source "$HOME/.keychain/$HOSTNAME-sh" - -} -``` - -###### SSH login without processing any login scripts - -```bash -ssh -tt user@host bash -``` - -###### SSH local port forwarding - -Example 1: - -```bash -# Forwarding our local 2250 port to nmap.org:443 from localhost through localhost -host1> ssh -L 2250:nmap.org:443 localhost - -# Connect to the service: -host1> curl -Iks --location -X GET https://localhost:2250 -``` - -Example 2: - -```bash -# Forwarding our local 9051 port to db.d.x:5432 from localhost through node.d.y -host1> ssh -nNT -L 9051:db.d.x:5432 node.d.y - -# Connect to the service: -host1> psql -U db_user -d db_dev -p 9051 -h localhost -``` - - * `-n` - redirects stdin from `/dev/null` - * `-N` - do not execute a remote command - * `-T` - disable pseudo-terminal allocation - -###### SSH remote port forwarding - -```bash -# Forwarding our local 9051 port to db.d.x:5432 from host2 through node.d.y -host1> ssh -nNT -R 9051:db.d.x:5432 node.d.y - -# Connect to the service: -host2> psql -U postgres -d postgres -p 8000 -h localhost -``` - -___ - -##### Tool: [linux-dev](https://www.tldp.org/LDP/abs/html/devref1.html) - -###### Testing remote connection to port - -```bash -timeout 1 bash -c "//" >/dev/null 2>&1 ; echo $? -``` - - * `` - set remote host - * `` - set destination port - -###### Read and write to TCP or UDP sockets with common bash tools - -```bash -exec 5<>/dev/tcp//; cat <&5 & cat >&5; exec 5>&- -``` - -___ - -##### Tool: [tcpdump](http://www.tcpdump.org/) - -###### Filter incoming (on interface) traffic (specific ) - -```bash -tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443 -``` - - * `-n` - don't convert addresses (`-nn` will not resolve hostnames or ports) - * `-e` - print the link-level headers - * `-i [iface|any]` - set interface - * `-Q|-D [in|out|inout]` - choose send/receive direction (`-D` - for old tcpdump versions) - * `host [ip|hostname]` - set host, also `[host not]` - * `[and|or]` - set logic - * `port [1-65535]` - set port number, also `[port not]` - -###### Filter incoming (on interface) traffic (specific ) and write to a file - -```bash -tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443 -c 5 -w tcpdump.pcap -``` - - * `-c [num]` - capture only num number of packets - * `-w [filename]` - write packets to file, `-r [filename]` - reading from file - -###### Capture all ICMP packets - -```bash -tcpdump -nei eth0 icmp -``` - -###### Check protocol used (TCP or UDP) for service - -```bash -tcpdump -nei eth0 tcp port 22 -vv -X | egrep "TCP|UDP" -``` - -###### Display ASCII text (to parse the output using grep or other) - -```bash -tcpdump -i eth0 -A -s0 port 443 -``` - -###### Grab everything between two keywords - -```bash -tcpdump -i eth0 port 80 -X | sed -n -e '/username/,/=ldap/ p' -``` - -###### Grab user and pass ever plain http - -```bash -tcpdump -i eth0 port http -l -A | egrep -i \ -'pass=|pwd=|log=|login=|user=|username=|pw=|passw=|passwd=|password=|pass:|user:|username:|password:|login:|pass |user ' \ ---color=auto --line-buffered -B20 -``` - -###### Extract HTTP User Agent from HTTP request header - -```bash -tcpdump -ei eth0 -nn -A -s1500 -l | grep "User-Agent:" -``` - -###### Capture only HTTP GET and POST packets - -```bash -tcpdump -ei eth0 -s 0 -A -vv \ -'tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x47455420' or 'tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x504f5354' -``` - -or simply: - -```bash -tcpdump -ei eth0 -s 0 -v -n -l | egrep -i "POST /|GET /|Host:" -``` - -###### Rotate capture files - -```bash -tcpdump -ei eth0 -w /tmp/capture-%H.pcap -G 3600 -C 200 -``` - - * `-G ` - pcap will be created every `` seconds - * `-C ` - close the current pcap and open a new one if is larger than `` - -###### Top hosts by packets - -```bash -tcpdump -ei enp0s25 -nnn -t -c 200 | cut -f 1,2,3,4 -d '.' | sort | uniq -c | sort -nr | head -n 20 -``` - -###### Excludes any RFC 1918 private address - -```bash -tcpdump -nei eth0 'not (src net (10 or 172.16/12 or 192.168/16) and dst net (10 or 172.16/12 or 192.168/16))' -``` -___ - -##### Tool: [ngrep](https://github.com/jpr5/ngrep) - -```bash -ngrep -d eth0 "www.domain.com" port 443 -``` - - * `-d [iface|any]` - set interface - * `[domain]` - set hostname - * `port [1-65535]` - set port number - -```bash -ngrep -d eth0 "www.domain.com" src host 10.240.20.2 and port 443 -``` - - * `(host [ip|hostname])` - filter by ip or hostname - * `(port [1-65535])` - filter by port number - -```bash -ngrep -d eth0 -qt -O ngrep.pcap "www.domain.com" port 443 -``` - - * `-q` - quiet mode (only payloads) - * `-t` - added timestamps - * `-O [filename]` - save output to file, `-I [filename]` - reading from file - -```bash -ngrep -d eth0 -qt 'HTTP' 'tcp' -``` - - * `HTTP` - show http headers - * `tcp|udp` - set protocol - * `[src|dst] host [ip|hostname]` - set direction for specific node - -```bash -ngrep -l -q -d eth0 -i "User-Agent: curl*" -``` - - * `-l` - stdout line buffered - * `-i` - case-insensitive search - -___ - -##### Tool: [hping3](https://github.com/antirez/hping) - -```bash -hping3 -V -p 80 -s 5050 www.google.com -``` - - * `-V|--verbose` - verbose mode - * `-p|--destport` - set destination port - * `-s|--baseport` - set source port - * `` - set scan type - * `-F|--fin` - set FIN flag, port open if no reply - * `-S|--syn` - set SYN flag - * `-P|--push` - set PUSH flag - * `-A|--ack` - set ACK flag (use when ping is blocked, RST response back if the port is open) - * `-U|--urg` - set URG flag - * `-Y|--ymas` - set Y unused flag (0x80 - nullscan), port open if no reply - * `-M 0 -UPF` - set TCP sequence number and scan type (URG+PUSH+FIN), port open if no reply - -```bash -hping3 -V -c 1 -1 -C 8 www.google.com -``` - - * `-c [num]` - packet count - * `-1` - set ICMP mode - * `-C|--icmptype [icmp-num]` - set icmp type (default icmp-echo = 8) - -```bash -hping3 -V -c 1000000 -d 120 -S -w 64 -p 80 --flood --rand-source -``` - - * `--flood` - sent packets as fast as possible (don't show replies) - * `--rand-source` - random source address mode - * `-d --data` - data size - * `-w|--win` - winsize (default 64) - -___ - -##### Tool: [nmap](https://nmap.org/) - -###### Ping scans the network - -```bash -nmap -sP 192.168.0.0/24 -``` - -###### Show only open ports - -```bash -nmap -F --open 192.168.0.0/24 -``` - -###### Full TCP port scan using with service version detection - -```bash -nmap -p 1-65535 -sV -sS -T4 192.168.0.0/24 -``` - -###### Nmap scan and pass output to Nikto - -```bash -nmap -p80,443 192.168.0.0/24 -oG - | nikto.pl -h - -``` - -###### Recon specific ip:service with Nmap NSE scripts stack - -```bash -# Set variables: -_hosts="192.168.250.10" -_ports="80,443" - -# Set Nmap NSE scripts stack: -_nmap_nse_scripts="+dns-brute,\ - +http-auth-finder,\ - +http-chrono,\ - +http-cookie-flags,\ - +http-cors,\ - +http-cross-domain-policy,\ - +http-csrf,\ - +http-dombased-xss,\ - +http-enum,\ - +http-errors,\ - +http-git,\ - +http-grep,\ - +http-internal-ip-disclosure,\ - +http-jsonp-detection,\ - +http-malware-host,\ - +http-methods,\ - +http-passwd,\ - +http-phpself-xss,\ - +http-php-version,\ - +http-robots.txt,\ - +http-sitemap-generator,\ - +http-shellshock,\ - +http-stored-xss,\ - +http-title,\ - +http-unsafe-output-escaping,\ - +http-useragent-tester,\ - +http-vhosts,\ - +http-waf-detect,\ - +http-waf-fingerprint,\ - +http-xssed,\ - +traceroute-geolocation.nse,\ - +ssl-enum-ciphers,\ - +whois-domain,\ - +whois-ip" - -# Set Nmap NSE script params: -_nmap_nse_scripts_args="dns-brute.domain=${_hosts},http-cross-domain-policy.domain-lookup=true," -_nmap_nse_scripts_args+="http-waf-detect.aggro,http-waf-detect.detectBodyChanges," -_nmap_nse_scripts_args+="http-waf-fingerprint.intensive=1" - -# Perform scan: -nmap --script="$_nmap_nse_scripts" --script-args="$_nmap_nse_scripts_args" -p "$_ports" "$_hosts" -``` - -___ - -##### Tool: [netcat](https://en.wikipedia.org/wiki/Netcat) - -```bash -nc -kl 5000 -``` - - * `-l` - listen for an incoming connection - * `-k` - listening after client has disconnected - * `>filename.out` - save receive data to file (optional) - -```bash -nc 192.168.0.1 5051 < filename.in -``` - - * `< filename.in` - send data to remote host - -```bash -nc -vz 10.240.30.3 5000 -``` - - * `-v` - verbose output - * `-z` - scan for listening daemons - -```bash -nc -vzu 10.240.30.3 1-65535 -``` - - * `-u` - scan only udp ports - -###### Transfer data file (archive) - -```bash -server> nc -l 5000 | tar xzvfp - -client> tar czvfp - /path/to/dir | nc 10.240.30.3 5000 -``` - -###### Launch remote shell - -```bash -# 1) -server> nc -l 5000 -e /bin/bash -client> nc 10.240.30.3 5000 - -# 2) -server> rm -f /tmp/f; mkfifo /tmp/f -server> cat /tmp/f | /bin/bash -i 2>&1 | nc -l 127.0.0.1 5000 > /tmp/f -client> nc 10.240.30.3 5000 -``` - -###### Simple file server - -```bash -while true ; do nc -l 5000 | tar -xvf - ; done -``` - -###### Simple minimal HTTP Server - -```bash -while true ; do nc -l -p 1500 -c 'echo -e "HTTP/1.1 200 OK\n\n $(date)"' ; done -``` - -###### Simple HTTP Server - - > Restarts web server after each request - remove `while` condition for only single connection. - -```bash -cat > index.html << __EOF__ - - - - - - - - - - -

- - Hello! It's a site. - -

- - - -__EOF__ -``` - -```bash -server> while : ; do \ -(echo -ne "HTTP/1.1 200 OK\r\nContent-Length: $(wc -c /" <"$_sent" & -sed "s/^/<= /" <"$_recv" & - -nc -l -p "$_listen_port" <"$_back" | \ -tee "$_sent" | \ -nc "$_bk_host" "$_bk_port" | \ -tee "$_recv" >"$_back" -``` - -```bash -server> chmod +x nc-proxy && ./nc-proxy 8080 192.168.252.10:8000 - lport: 8080 -bk_host: 192.168.252.10 -bk_port: 8000 - -client> http -p h 10.240.30.3:8080 -HTTP/1.1 200 OK -Accept-Ranges: bytes -Cache-Control: max-age=31536000 -Content-Length: 2748 -Content-Type: text/html; charset=utf-8 -Date: Sun, 01 Jul 2018 20:12:08 GMT -Last-Modified: Sun, 01 Apr 2018 21:53:37 GMT -``` - -###### Create a single-use TCP or UDP proxy - -```bash -### TCP -> TCP -nc -l -p 2000 -c "nc [ip|hostname] 3000" - -### TCP -> UDP -nc -l -p 2000 -c "nc -u [ip|hostname] 3000" - -### UDP -> UDP -nc -l -u -p 2000 -c "nc -u [ip|hostname] 3000" - -### UDP -> TCP -nc -l -u -p 2000 -c "nc [ip|hostname] 3000" -``` - -___ - -##### Tool: [gnutls-cli](https://gnutls.org/manual/html_node/gnutls_002dcli-Invocation.html) - -###### Testing connection to remote host (with SNI support) - -```bash -gnutls-cli -p 443 google.com -``` - -###### Testing connection to remote host (without SNI support) - -```bash -gnutls-cli --disable-sni -p 443 google.com -``` - -___ - -##### Tool: [socat](http://www.dest-unreach.org/socat/doc/socat.html) - -###### Testing remote connection to port - -```bash -socat - TCP4:10.240.30.3:22 -``` - - * `-` - standard input (STDIO) - * `TCP4:` - set tcp4 connection with specific params - * `[hostname|ip]` - set hostname/ip - * `[1-65535]` - set port number - -###### Redirecting TCP-traffic to a UNIX domain socket under Linux - -```bash -socat TCP-LISTEN:1234,bind=127.0.0.1,reuseaddr,fork,su=nobody,range=127.0.0.0/8 UNIX-CLIENT:/tmp/foo -``` - - * `TCP-LISTEN:` - set tcp listen with specific params - * `[1-65535]` - set port number - * `bind=[hostname|ip]` - set bind hostname/ip - * `reuseaddr` - allows other sockets to bind to an address - * `fork` - keeps the parent process attempting to produce more connections - * `su=nobody` - set user - * `range=[ip-range]` - ip range - * `UNIX-CLIENT:` - communicates with the specified peer socket - * `filename` - define socket - -___ - -##### Tool: [p0f](http://lcamtuf.coredump.cx/p0f3/) - -###### Set iface in promiscuous mode and dump traffic to the log file - -```bash -p0f -i enp0s25 -p -d -o /dump/enp0s25.log -``` - - * `-i` - listen on the specified interface - * `-p` - set interface in promiscuous mode - * `-d` - fork into background - * `-o` - output file - -___ - -##### Tool: [netstat](https://en.wikipedia.org/wiki/Netstat) - -###### Graph # of connections for each hosts - -```bash -netstat -an | awk '/ESTABLISHED/ { split($5,ip,":"); if (ip[1] !~ /^$/) print ip[1] }' | \ -sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }' -``` - -###### Monitor open connections for specific port including listen, count and sort it per IP - -```bash -watch "netstat -plan | grep :443 | awk {'print \$5'} | cut -d: -f 1 | sort | uniq -c | sort -nk 1" -``` - -###### Grab banners from local IPv4 listening ports - -```bash -netstat -nlt | grep 'tcp ' | grep -Eo "[1-9][0-9]*" | xargs -I {} sh -c "echo "" | nc -v -n -w1 127.0.0.1 {}" -``` - -___ - -##### Tool: [rsync](https://en.wikipedia.org/wiki/Rsync) - -###### Rsync remote data as root using sudo - -```bash -rsync --rsync-path 'sudo rsync' username@hostname:/path/to/dir/ /local/ -``` - -___ - -##### Tool: [host](https://en.wikipedia.org/wiki/Host_(Unix)) - -###### Resolves the domain name (using external dns server) - -```bash -host google.com 9.9.9.9 -``` - -###### Checks the domain administrator (SOA record) - -```bash -host -t soa google.com 9.9.9.9 -``` - -___ - -##### Tool: [dig](https://en.wikipedia.org/wiki/Dig_(command)) - -###### Resolves the domain name (short output) - -```bash -dig google.com +short -``` - -###### Lookup NS record for specific domain - -```bash -dig @9.9.9.9 google.com NS -``` - -###### Query only answer section - -```bash -dig google.com +nocomments +noquestion +noauthority +noadditional +nostats -``` - -###### Query ALL DNS Records - -```bash -dig google.com ANY +noall +answer -``` - -###### DNS Reverse Look-up - -```bash -dig -x 172.217.16.14 +short -``` - -___ - -##### Tool: [certbot](https://certbot.eff.org/) - -###### Generate multidomain certificate - -```bash -certbot certonly -d example.com -d www.example.com -``` - -###### Generate wildcard certificate - -```bash -certbot certonly --manual --preferred-challenges=dns -d example.com -d *.example.com -``` - -###### Generate certificate with 4096 bit private key - -```bash -certbot certonly -d example.com -d www.example.com --rsa-key-size 4096 -``` - -___ - -##### Tool: [network-other](https://github.com/trimstray/the-book-of-secret-knowledge#tool-network-other) - -###### Get all subnets for specific AS (Autonomous system) - -```bash -AS="AS32934" -whois -h whois.radb.net -- "-i origin ${AS}" | \ -grep "^route:" | \ -cut -d ":" -f2 | \ -sed -e 's/^[ \t]//' | \ -sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | \ -cut -d ":" -f2 | \ -sed -e 's/^[ \t]/allow /' | \ -sed 's/$/;/' | \ -sed 's/allow */subnet -> /g' -``` - -###### Resolves domain name from dns.google.com with curl and jq - -```bash -_dname="google.com" ; curl -s "https://dns.google.com/resolve?name=${_dname}&type=A" | jq . -``` - -##### Tool: [git](https://git-scm.com/) - -###### Log alias for a decent view of your repo - -```bash -# 1) -git log --oneline --decorate --graph --all - -# 2) -git log --graph \ ---pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' \ ---abbrev-commit -``` - -___ - -##### Tool: [python](https://www.python.org/) - -###### Static HTTP web server - -```bash -# Python 3.x -python3 -m http.server 8000 --bind 127.0.0.1 - -# Python 2.x -python -m SimpleHTTPServer 8000 -``` - -###### Static HTTP web server with SSL support - -```bash -# Python 3.x -from http.server import HTTPServer, BaseHTTPRequestHandler -import ssl - -httpd = HTTPServer(('localhost', 4443), BaseHTTPRequestHandler) - -httpd.socket = ssl.wrap_socket (httpd.socket, - keyfile="path/to/key.pem", - certfile='path/to/cert.pem', server_side=True) - -httpd.serve_forever() - -# Python 2.x -import BaseHTTPServer, SimpleHTTPServer -import ssl - -httpd = BaseHTTPServer.HTTPServer(('localhost', 4443), - SimpleHTTPServer.SimpleHTTPRequestHandler) - -httpd.socket = ssl.wrap_socket (httpd.socket, - keyfile="path/tp/key.pem", - certfile='path/to/cert.pem', server_side=True) - -httpd.serve_forever() -``` - -###### Encode base64 - -```bash -python -m base64 -e <<< "sample string" -``` - -###### Decode base64 - -```bash -python -m base64 -d <<< "dGhpcyBpcyBlbmNvZGVkCg==" -``` - -##### Tool: [awk](http://www.grymoire.com/Unix/Awk.html) - -###### Search for matching lines - -```bash -# egrep foo -awk '/foo/' filename -``` - -###### Search non matching lines - -```bash -# egrep -v foo -awk '!/foo/' filename -``` - -###### Print matching lines with numbers - -```bash -# egrep -n foo -awk '/foo/{print FNR,$0}' filename -``` - -###### Print the last column - -```bash -awk '{print $NF}' filename -``` - -###### Find all the lines longer than 80 characters - -```bash -awk 'length($0)>80{print FNR,$0}' filename -``` - -###### Print only lines of less than 80 characters - -```bash -awk 'length < 80' filename -``` - -###### Print double new lines a file - -```bash -awk '1; { print "" }' filename -``` - -###### Print line numbers - -```bash -awk '{ print FNR "\t" $0 }' filename -awk '{ printf("%5d : %s\n", NR, $0) }' filename # in a fancy manner -``` - -###### Print line numbers for only non-blank lines - -```bash -awk 'NF { $0=++a " :" $0 }; { print }' filename -``` - -###### Print the line and the next two (i=5) lines after the line matching regexp - -```bash -awk '/foo/{i=5+1;}{if(i){i--; print;}}' filename -``` - -###### Print the lines starting at the line matching 'server {' until the line matching '}' - -```bash -awk '/server {/,/}/' filename -``` - -###### Print multiple columns with separators - -```bash -awk -F' ' '{print "ip:\t" $2 "\n port:\t" $3' filename -``` - -###### Remove empty lines - -```bash -awk 'NF > 0' filename - -# alternative: -awk NF filename -``` - -###### Delete trailing white space (spaces, tabs) - -```bash -awk '{sub(/[ \t]*$/, "");print}' filename -``` - -###### Delete leading white space - -```bash -awk '{sub(/^[ \t]+/, ""); print}' filename -``` - -###### Remove duplicate consecutive lines - -```bash -# uniq -awk 'a !~ $0{print}; {a=$0}' filename -``` - -###### Remove duplicate entries in a file without sorting - -```bash -awk '!x[$0]++' filename -``` - -###### Exclude multiple columns - -```bash -awk '{$1=$3=""}1' filename -``` - -###### Substitute foo for bar on lines matching regexp - -```bash -awk '/regexp/{gsub(/foo/, "bar")};{print}' filename -``` - -###### Add some characters at the beginning of matching lines - -```bash -awk '/regexp/{sub(/^/, "++++"); print;next;}{print}' filename -``` - -###### Get the last hour of Apache logs - -```bash -awk '/'$(date -d "1 hours ago" "+%d\\/%b\\/%Y:%H:%M")'/,/'$(date "+%d\\/%b\\/%Y:%H:%M")'/ { print $0 }' \ -/var/log/httpd/access_log -``` - -___ - -##### Tool: [sed](http://www.grymoire.com/Unix/Sed.html) - -###### Print a specific line from a file - -```bash -sed -n 10p /path/to/file -``` - -###### Remove a specific line from a file - -```bash -sed -i 10d /path/to/file -# alternative (BSD): sed -i'' 10d /path/to/file -``` - -###### Remove a range of lines from a file - -```bash -sed -i -re ',d' -``` - -###### Replace newline(s) with a space - -```bash -sed ':a;N;$!ba;s/\n/ /g' /path/to/file - -# cross-platform compatible syntax: -sed -e ':a' -e 'N' -e '$!ba' -e 's/\n/ /g' /path/to/file -``` - -- `:a` create a label `a` -- `N` append the next line to the pattern space -- `$!` if not the last line, ba branch (go to) label `a` -- `s` substitute, `/\n/` regex for new line, `/ /` by a space, `/g` global match (as many times as it can) - -Alternatives: - -```bash -# perl version (sed-like speed): -perl -p -e 's/\n/ /' /path/to/file - -# bash version (slow): -while read line ; do printf "%s" "$line " ; done < file -``` - -###### Delete string +N next lines - -```bash -sed '/start/,+4d' /path/to/file -``` - -___ - -##### Tool: [grep](http://www.grymoire.com/Unix/Grep.html) - -###### Search for a "pattern" inside all files in the current directory - -```bash -grep -rn "pattern" -grep -RnisI "pattern" * -fgrep "pattern" * -R -``` - -###### Show only for multiple patterns - -```bash -grep 'INFO*'\''WARN' filename -grep 'INFO\|WARN' filename -grep -e INFO -e WARN filename -grep -E '(INFO|WARN)' filename -egrep "INFO|WARN" filename -``` - -###### Except multiple patterns - -```bash -grep -vE '(error|critical|warning)' filename -``` - -###### Show data from file without comments - -```bash -grep -v ^[[:space:]]*# filename -``` - -###### Show data from file without comments and new lines - -```bash -egrep -v '#|^$' filename -``` - -###### Show strings with a dash/hyphen - -```bash -grep -e -- filename -grep -- -- filename -grep "\-\-" filename -``` - -###### Remove blank lines from a file and save output to new file - -```bash -grep . filename > newfilename -``` - -##### Tool: [perl](https://www.perl.org/) - -###### Search and replace (in place) - -```bash -perl -i -pe's/SEARCH/REPLACE/' filename -``` - -###### Edit of `*.conf` files changing all foo to bar (and backup original) - -```bash -perl -p -i.orig -e 's/\bfoo\b/bar/g' *.conf -``` - -###### Prints the first 20 lines from `*.conf` files - -```bash -perl -pe 'exit if $. > 20' *.conf -``` - -###### Search lines 10 to 20 - -```bash -perl -ne 'print if 10 .. 20' filename -``` - -###### Delete first 10 lines (and backup original) - -```bash -perl -i.orig -ne 'print unless 1 .. 10' filename -``` - -###### Delete all but lines between foo and bar (and backup original) - -```bash -perl -i.orig -ne 'print unless /^foo$/ .. /^bar$/' filename -``` - -###### Reduce multiple blank lines to a single line - -```bash -perl -p -i -00pe0 filename -``` - -###### Convert tabs to spaces (1t = 2sp) - -```bash -perl -p -i -e 's/\t/ /g' filename -``` - -###### Read input from a file and report number of lines and characters - -```bash -perl -lne '$i++; $in += length($_); END { print "$i lines, $in characters"; }' filename -``` - -#### Shell Tricks  [[TOC]](#anger-table-of-contents) - -When you get a shell, it is generally not very clean, but after following these steps, you will have a fairly clean and comfortable shell to work with. - -1) `script /dev/null -c bash` -2) Ctrl-Z (to send it to background) -3) `stty raw -echo; fg` (returns the shell to foreground) -4) `reset` (to reset terminal) -5) `xterm` (when asked for terminal type) -6) `export TERM=xterm; export SHELL=bash` - -#### Shell functions  [[TOC]](#anger-table-of-contents) - -##### Table of Contents - -- [Domain resolve](#domain-resolve) -- [Get ASN](#get-asn) - -###### Domain resolve - -```bash -# Dependencies: -# - curl -# - jq - -function DomainResolve() { - - local _host="$1" - - local _curl_base="curl --request GET" - local _timeout="15" - - _host_ip=$($_curl_base -ks -m "$_timeout" "https://dns.google.com/resolve?name=${_host}&type=A" | \ - jq '.Answer[0].data' | tr -d "\"" 2>/dev/null) - - if [[ -z "$_host_ip" ]] || [[ "$_host_ip" == "null" ]] ; then - - echo -en "Unsuccessful domain name resolution.\\n" - - else - - echo -en "$_host > $_host_ip\\n" - - fi - -} -``` - -Example: - -```bash -shell> DomainResolve nmap.org -nmap.org > 45.33.49.119 - -shell> DomainResolve nmap.org -Unsuccessful domain name resolution. -``` - -###### Get ASN - -```bash -# Dependencies: -# - curl - -function GetASN() { - - local _ip="$1" - - local _curl_base="curl --request GET" - local _timeout="15" - - _asn=$($_curl_base -ks -m "$_timeout" "http://ip-api.com/line/${_ip}?fields=as") - - _state=$(echo $?) - - if [[ -z "$_ip" ]] || [[ "$_ip" == "null" ]] || [[ "$_state" -ne 0 ]]; then - - echo -en "Unsuccessful ASN gathering.\\n" - - else - - echo -en "$_ip > $_asn\\n" - - fi - -} -``` - -Example: - -```bash -shell> GetASN 1.1.1.1 -1.1.1.1 > AS13335 Cloudflare, Inc. - -shell> GetASN 0.0.0.0 -Unsuccessful ASN gathering. -``` +

\ No newline at end of file diff --git a/tools/cross-domain/learning-resources/daily-knowledge-news.md b/documentation/learning-resources/daily-knowledge-news.md similarity index 100% rename from tools/cross-domain/learning-resources/daily-knowledge-news.md rename to documentation/learning-resources/daily-knowledge-news.md diff --git a/tools/cross-domain/manuals-howtos-tutorials.md b/documentation/manuals-howtos-guides/shell-one-liners.md similarity index 100% rename from tools/cross-domain/manuals-howtos-tutorials.md rename to documentation/manuals-howtos-guides/shell-one-liners.md diff --git a/tools/cross-domain/other-cheat-sheets.md b/documentation/manuals-howtos-guides/shell-tricks-functions.md similarity index 100% rename from tools/cross-domain/other-cheat-sheets.md rename to documentation/manuals-howtos-guides/shell-tricks-functions.md diff --git a/documentation/other-cheat-sheets.md b/documentation/other-cheat-sheets.md new file mode 100644 index 0000000..e69de29 diff --git a/documentation/readme - to refactor.md b/documentation/readme - to refactor.md new file mode 100644 index 0000000..d7985b9 --- /dev/null +++ b/documentation/readme - to refactor.md @@ -0,0 +1,2849 @@ + +###### DNS Servers list (privacy) + +| IP | URL | +| :--- | :--- | +| **`84.200.69.80`** | [dns.watch](https://dns.watch/) | +| **`94.247.43.254`** | [opennic.org](https://www.opennic.org/) | +| **`64.6.64.6`** | [verisign.com](https://www.verisign.com/en_US/security-services/public-dns/index.xhtml) | +| **`89.233.43.71`** | [censurfridns.dk](https://blog.uncensoreddns.org/) | +| **`1.1.1.1`** | [cloudflare.com](https://1.1.1.1/) | +###### TOP Browser extensions + +| Extension name | Description | +| :--- | :--- | +| **`IPvFoo`** | Display the server IP address and HTTPS information across all page elements. | +| **`FoxyProxy`** | Simplifies configuring browsers to access proxy-servers. | +| **`HTTPS Everywhere`** | Automatically use HTTPS security on many sites. | +| **`uMatrix`** | Point & click to forbid/allow any class of requests made by your browser. | +| **`uBlock Origin`** | An efficient blocker: easy on memory and CPU footprint. | +| **`Session Buddy`** | Manage browser tabs and bookmarks with ease. | +| **`SuperSorter`** | Sort bookmarks recursively, delete duplicates, merge folders, and more. | +| **`Clear Cache`** | Clear your cache and browsing data. | +| **`d3coder`** | Encoding/Decoding plugin for various types of encoding. | +| **`Web Developer`** | Adds a toolbar button with various web developer tools. | +| **`ThreatPinch Lookup`** | Add threat intelligence hover tool tips. | + +###### TOP Burp extensions + +| Extension name | Description | +| :--- | :--- | +| **`Active Scan++`** | Extends Burp's active and passive scanning capabilities. | +| **`Autorize`** | Automatically detects authorization enforcement. | +| **`AuthMatrix`** | A simple matrix grid to define the desired levels of access privilege. | +| **`Logger++`** | Logs requests and responses for all Burp tools in a sortable table. | +| **`Bypass WAF`** | Adds headers useful for bypassing some WAF devices. | +| **`JSON Beautifier`** | Beautifies JSON content in the HTTP message viewer. | +| **`JSON Web Tokens`** | Enables Burp to decode and manipulate JSON web tokens. | +| **`CSP Auditor`** | Displays CSP headers for responses, and passively reports CSP weaknesses. | +| **`CSP-Bypass`** | Passively scans for CSP headers that contain known bypasses. | +| **`Hackvertor`** | Converts data using a tag-based configuration to apply various encoding. | +| **`HTML5 Auditor`** | Scans for usage of risky HTML5 features. | +| **`Software Vulnerability Scanner`** | Vulnerability scanner based on vulners.com audit API. | +| **`Turbo Intruder`** | Is a powerful bruteforcing tool. | +| **`Upload Scanner`** | Upload a number of different file types, laced with different forms of payload. | + +###### Hack Mozilla Firefox address bar + +In Firefox's address bar, you can limit results by typing special characters before or after your term: + +- `^` - for matches in your browsing history +- `*` - for matches in your bookmarks. +- `%` - for matches in your currently open tabs. +- `#` - for matches in page titles. +- `@` - for matches in web addresses. + +###### Chrome hidden commands + +- `chrome://chrome-urls` - list of all commands +- `chrome://flags` - enable experiments and development features +- `chrome://interstitials` - errors and warnings +- `chrome://net-internals` - network internals (events, dns, cache) +- `chrome://network-errors` - network errors +- `chrome://net-export` - start logging future network activity to a file +- `chrome://safe-browsing` - safe browsing options +- `chrome://user-actions` - record all user actions +- `chrome://restart` - restart chrome +- `chrome://dino` - ERR_INTERNET_DISCONNECTED... +- `cache:` - view the cached version of the web page + +###### Bypass WAFs by Shortening IP Address (by [0xInfection](https://x.com/0xInfection)) + +IP addresses can be shortened by dropping the zeroes: + +``` +http://1.0.0.1 → http://1.1 +http://127.0.0.1 → http://127.1 +http://192.168.0.1 → http://192.168.1 + +http://0xC0A80001 or http://3232235521 → 192.168.0.1 +http://192.168.257 → 192.168.1.1 +http://192.168.516 → 192.168.2.4 +``` + + > This bypasses WAF filters for SSRF, open-redirect, etc where any IP as input gets blacklisted. + +###### Hashing, encryption and encoding (by [Michal Špaček](https://twitter.com/spazef0rze)) + +_Hashing_ + +plaintext :arrow_right: hash
+hash :no_entry: plaintext + +_Symmetric encryption_ + +plaintext :arrow_right: :key: :arrow_right: ciphertext
+plaintext :arrow_left: :key: :arrow_left: ciphertext
+(:key: shared key) + +_Asymmetric encryption_ + +plaintext :arrow_right: :key: :arrow_right: ciphertext
+plaintext :arrow_left: :part_alternation_mark: :arrow_left: ciphertext
+(:key: public key, :part_alternation_mark: private key)
+ +_Encoding_ + +text :arrow_right: encoded
+text :arrow_left: encoded + +#### Shell One-liners  [[TOC]](#anger-table-of-contents) + +##### Table of Contents + + * [terminal](#tool-terminal) + * [busybox](#tool-busybox) + * [mount](#tool-mount) + * [fuser](#tool-fuser) + * [lsof](#tool-lsof) + * [ps](#tool-ps) + * [top](#tool-top) + * [vmstat](#tool-vmstat) + * [iostat](#tool-iostat) + * [strace](#tool-strace) + * [kill](#tool-kill) + * [find](#tool-find) + * [diff](#tool-diff) + * [vimdiff](#tool-vimdiff) + * [tail](#tool-tail) + * [cpulimit](#tool-cpulimit) + * [pwdx](#tool-pwdx) + * [tr](#tool-tr) + * [chmod](#tool-chmod) + * [who](#tool-who) + * [last](#tool-last) + * [screen](#tool-screen) + * [script](#tool-script) + * [du](#tool-du) + * [inotifywait](#tool-inotifywait) + * [openssl](#tool-openssl) + * [secure-delete](#tool-secure-delete) + * [dd](#tool-dd) + * [gpg](#tool-gpg) + * [system-other](#tool-system-other) + * [curl](#tool-curl) + * [httpie](#tool-httpie) + * [ssh](#tool-ssh) + * [linux-dev](#tool-linux-dev) + * [tcpdump](#tool-tcpdump) + * [tcpick](#tool-tcpick) + * [ngrep](#tool-ngrep) + * [hping3](#tool-hping3) + * [nmap](#tool-nmap) + * [netcat](#tool-netcat) + * [socat](#tool-socat) + * [p0f](#tool-p0f) + * [gnutls-cli](#tool-gnutls-cli) + * [netstat](#tool-netstat) + * [rsync](#tool-rsync) + * [host](#tool-host) + * [dig](#tool-dig) + * [certbot](#tool-certbot) + * [network-other](#tool-network-other) + * [git](#tool-git) + * [awk](#tool-awk) + * [sed](#tool-sed) + * [grep](#tool-grep) + * [perl](#tool-perl) + +##### Tool: [terminal](https://en.wikipedia.org/wiki/Linux_console) + +###### Reload shell without exit + +```bash +exec $SHELL -l +``` + +###### Close shell keeping all subprocess running + +```bash +disown -a && exit +``` + +###### Exit without saving shell history + +```bash +kill -9 $$ +unset HISTFILE && exit +``` + +###### Perform a branching conditional + +```bash +true && echo success +false || echo failed +``` + +###### Pipe stdout and stderr to separate commands + +```bash +some_command > >(/bin/cmd_for_stdout) 2> >(/bin/cmd_for_stderr) +``` + +###### Redirect stdout and stderr each to separate files and print both to the screen + +```bash +(some_command 2>&1 1>&3 | tee errorlog ) 3>&1 1>&2 | tee stdoutlog +``` + +###### List of commands you use most often + +```bash +history | \ +awk '{CMD[$2]++;count++;}END { for (a in CMD)print CMD[a] " " CMD[a]/count*100 "% " a;}' | \ +grep -v "./" | \ +column -c3 -s " " -t | \ +sort -nr | nl | head -n 20 +``` + +###### Sterilize bash history + +```bash +function sterile() { + + history | awk '$2 != "history" { $1=""; print $0 }' | egrep -vi "\ +curl\b+.*(-E|--cert)\b+.*\b*|\ +curl\b+.*--pass\b+.*\b*|\ +curl\b+.*(-U|--proxy-user).*:.*\b*|\ +curl\b+.*(-u|--user).*:.*\b* +.*(-H|--header).*(token|auth.*)\b+.*|\ +wget\b+.*--.*password\b+.*\b*|\ +http.?://.+:.+@.*\ +" > $HOME/histbuff; history -r $HOME/histbuff; + +} + +export PROMPT_COMMAND="sterile" +``` + + > Look also: [A naive utility to censor credentials in command history](https://github.com/lbonanomi/go/blob/master/revisionist.go). + +###### Quickly backup a file + +```bash +cp filename{,.orig} +``` + +###### Empty a file (truncate to 0 size) + +```bash +>filename +``` + +###### Delete all files in a folder that don't match a certain file extension + +```bash +rm !(*.foo|*.bar|*.baz) +``` + +###### Pass multi-line string to a file + +```bash +# cat >filename ... - overwrite the file +# cat >>filename ... - append to a file +cat > filename << __EOF__ +data data data +__EOF__ +``` + +###### Edit a file on a remote host using vim + +```bash +vim scp://user@host//etc/fstab +``` + +###### Create a directory and change into it at the same time + +```bash +mkd() { mkdir -p "$@" && cd "$@"; } +``` + +###### Convert uppercase files to lowercase files + +```bash +rename 'y/A-Z/a-z/' * +``` + +###### Print a row of characters across the terminal + +```bash +printf "%`tput cols`s" | tr ' ' '#' +``` + +###### Show shell history without line numbers + +```bash +history | cut -c 8- +fc -l -n 1 | sed 's/^\s*//' +``` + +###### Run command(s) after exit session + +```bash +cat > /etc/profile << __EOF__ +_after_logout() { + + username=$(whoami) + + for _pid in $(ps afx | grep sshd | grep "$username" | awk '{print $1}') ; do + + kill -9 $_pid + + done + +} +trap _after_logout EXIT +__EOF__ +``` + +###### Generate a sequence of numbers + +```bash +for ((i=1; i<=10; i+=2)) ; do echo $i ; done +# alternative: seq 1 2 10 + +for ((i=5; i<=10; ++i)) ; do printf '%02d\n' $i ; done +# alternative: seq -w 5 10 + +for i in {1..10} ; do echo $i ; done +``` + +###### Simple Bash filewatching + +```bash +unset MAIL; export MAILCHECK=1; export MAILPATH='$FILE_TO_WATCH?$MESSAGE' +``` + +--- + +##### Tool: [busybox](https://www.busybox.net/) + +###### Static HTTP web server + +```bash +busybox httpd -p $PORT -h $HOME [-c httpd.conf] +``` + +___ + +##### Tool: [mount](https://en.wikipedia.org/wiki/Mount_(Unix)) + +###### Mount a temporary ram partition + +```bash +mount -t tmpfs tmpfs /mnt -o size=64M +``` + + * `-t` - filesystem type + * `-o` - mount options + +###### Remount a filesystem as read/write + +```bash +mount -o remount,rw / +``` + +___ + +##### Tool: [fuser](https://en.wikipedia.org/wiki/Fuser_(Unix)) + +###### Show which processes use the files/directories + +```bash +fuser /var/log/daemon.log +fuser -v /home/supervisor +``` + +###### Kills a process that is locking a file + +```bash +fuser -ki filename +``` + + * `-i` - interactive option + +###### Kills a process that is locking a file with specific signal + +```bash +fuser -k -HUP filename +``` + + * `--list-signals` - list available signal names + +###### Show what PID is listening on specific port + +```bash +fuser -v 53/udp +``` + +###### Show all processes using the named filesystems or block device + +```bash +fuser -mv /var/www +``` + +___ + +##### Tool: [lsof](https://en.wikipedia.org/wiki/Lsof) + +###### Show process that use internet connection at the moment + +```bash +lsof -P -i -n +``` + +###### Show process that use specific port number + +```bash +lsof -i tcp:443 +``` + +###### Lists all listening ports together with the PID of the associated process + +```bash +lsof -Pan -i tcp -i udp +``` + +###### List all open ports and their owning executables + +```bash +lsof -i -P | grep -i "listen" +``` + +###### Show all open ports + +```bash +lsof -Pnl -i +``` + +###### Show open ports (LISTEN) + +```bash +lsof -Pni4 | grep LISTEN | column -t +``` + +###### List all files opened by a particular command + +```bash +lsof -c "process" +``` + +###### View user activity per directory + +```bash +lsof -u username -a +D /etc +``` + +###### Show 10 largest open files + +```bash +lsof / | \ +awk '{ if($7 > 1048576) print $7/1048576 "MB" " " $9 " " $1 }' | \ +sort -n -u | tail | column -t +``` + +###### Show current working directory of a process + +```bash +lsof -p | grep cwd +``` + +___ + +##### Tool: [ps](https://en.wikipedia.org/wiki/Ps_(Unix)) + +###### Show a 4-way scrollable process tree with full details + +```bash +ps awwfux | less -S +``` + +###### Processes per user counter + +```bash +ps hax -o user | sort | uniq -c | sort -r +``` + +###### Show all processes by name with main header + +```bash +ps -lfC nginx +``` + +___ + +##### Tool: [find](https://en.wikipedia.org/wiki/Find_(Unix)) + +###### Find files that have been modified on your system in the past 60 minutes + +```bash +find / -mmin 60 -type f +``` + +###### Find all files larger than 20M + +```bash +find / -type f -size +20M +``` + +###### Find duplicate files (based on MD5 hash) + +```bash +find -type f -exec md5sum '{}' ';' | sort | uniq --all-repeated=separate -w 33 +``` + +###### Change permission only for files + +```bash +cd /var/www/site && find . -type f -exec chmod 766 {} \; +cd /var/www/site && find . -type f -exec chmod 664 {} + +``` + +###### Change permission only for directories + +```bash +cd /var/www/site && find . -type d -exec chmod g+x {} \; +cd /var/www/site && find . -type d -exec chmod g+rwx {} + +``` + +###### Find files and directories for specific user/group + +```bash +# User: +find . -user -print +find /etc -type f -user -name "*.conf" + +# Group: +find /opt -group +find /etc -type f -group -iname "*.conf" +``` + +###### Find files and directories for all without specific user/group + +```bash +# User: +find . \! -user -print + +# Group: +find . \! -group +``` + +###### Looking for files/directories that only have certain permission + +```bash +# User +find . -user -perm -u+rw # -rw-r--r-- +find /home -user $(whoami) -perm 777 # -rwxrwxrwx + +# Group: +find /home -type d -group -perm 755 # -rwxr-xr-x +``` + +###### Delete older files than 60 days + +```bash +find . -type f -mtime +60 -delete +``` + +###### Recursively remove all empty sub-directories from a directory + +```bash +find . -depth -type d -empty -exec rmdir {} \; +``` + +###### How to find all hard links to a file + +```bash +find -xdev -samefile filename +``` + +###### Recursively find the latest modified files + +```bash +find . -type f -exec stat --format '%Y :%y %n' "{}" \; | sort -nr | cut -d: -f2- | head +``` + +###### Recursively find/replace of a string with sed + +```bash +find . -not -path '*/\.git*' -type f -print0 | xargs -0 sed -i 's/foo/bar/g' +``` + +###### Recursively find/replace of a string in directories and file names + +```bash +find . -depth -name '*test*' -execdir bash -c 'mv -v "$1" "${1//foo/bar}"' _ {} \; +``` + +###### Recursively find suid executables + +```bash +find / \( -perm -4000 -o -perm -2000 \) -type f -exec ls -la {} \; +``` + +___ + +##### Tool: [top](https://en.wikipedia.org/wiki/Top_(software)) + +###### Use top to monitor only all processes with the specific string + +```bash +top -p $(pgrep -d , ) +``` + + * `` - process containing string (eg. nginx, worker) + +___ + +##### Tool: [vmstat](https://en.wikipedia.org/wiki/Vmstat) + +###### Show current system utilization (fields in kilobytes) + +```bash +vmstat 2 20 -t -w +``` + + * `2` - number of times with a defined time interval (delay) + * `20` - each execution of the command (count) + * `-t` - show timestamp + * `-w` - wide output + * `-S M` - output of the fields in megabytes instead of kilobytes + +###### Show current system utilization will get refreshed every 5 seconds + +```bash +vmstat 5 -w +``` + +###### Display report a summary of disk operations + +```bash +vmstat -D +``` + +###### Display report of event counters and memory stats + +```bash +vmstat -s +``` + +###### Display report about kernel objects stored in slab layer cache + +```bash +vmstat -m +``` + +##### Tool: [iostat](https://en.wikipedia.org/wiki/Iostat) + +###### Show information about the CPU usage, and I/O statistics about all the partitions + +```bash +iostat 2 10 -t -m +``` + + * `2` - number of times with a defined time interval (delay) + * `10` - each execution of the command (count) + * `-t` - show timestamp + * `-m` - fields in megabytes (`-k` - in kilobytes, default) + +###### Show information only about the CPU utilization + +```bash +iostat 2 10 -t -m -c +``` + +###### Show information only about the disk utilization + +```bash +iostat 2 10 -t -m -d +``` + +###### Show information only about the LVM utilization + +```bash +iostat -N +``` + +___ + +##### Tool: [strace](https://en.wikipedia.org/wiki/Strace) + +###### Track with child processes + +```bash +# 1) +strace -f -p $(pidof glusterfsd) + +# 2) +strace -f $(pidof php-fpm | sed 's/\([0-9]*\)/\-p \1/g') +``` + +###### Track process with 30 seconds limit + +```bash +timeout 30 strace $(< /var/run/zabbix/zabbix_agentd.pid) +``` + +###### Track processes and redirect output to a file + +```bash +ps auxw | grep '[a]pache' | awk '{print " -p " $2}' | \ +xargs strace -o /tmp/strace-apache-proc.out +``` + +###### Track with print time spent in each syscall and limit length of print strings + +```bash +ps auxw | grep '[i]init_policy' | awk '{print " -p " $2}' | \ +xargs strace -f -e trace=network -T -s 10000 +``` + +###### Track the open request of a network port + +```bash +strace -f -e trace=bind nc -l 80 +``` + +###### Track the open request of a network port (show TCP/UDP) + +```bash +strace -f -e trace=network nc -lu 80 +``` + +___ + +##### Tool: [kill](https://en.wikipedia.org/wiki/Kill_(command)) + +###### Kill a process running on port + +```bash +kill -9 $(lsof -i : | awk '{l=$2} END {print l}') +``` + +___ + +##### Tool: [diff](https://en.wikipedia.org/wiki/Diff) + +###### Compare two directory trees + +```bash +diff <(cd directory1 && find | sort) <(cd directory2 && find | sort) +``` + +###### Compare output of two commands + +```bash +diff <(cat /etc/passwd) <(cut -f2 /etc/passwd) +``` + +___ + +##### Tool: [vimdiff](https://git-scm.com/docs/vimdiff) + +###### Highlight the exact differences, based on characters and words + +```bash +vimdiff file1 file2 +``` + +###### Compare two JSON files + +```bash +vimdiff <(jq -S . A.json) <(jq -S . B.json) +``` + +###### Compare Hex dump + +```bash +d(){ vimdiff <(f $1) <(f $2);};f(){ hexdump -C $1 | cut -d' ' -f3- | tr -s ' ';}; d ~/bin1 ~/bin2 +``` + +###### diffchar + +Save [diffchar](https://raw.githubusercontent.com/vim-scripts/diffchar.vim/master/plugin/diffchar.vim) @ `~/.vim/plugins` + +Click `F7` to switch between diff modes + +Usefull `vimdiff` commands: + +* `qa` to exit all windows +* `:vertical resize 70` to resize window +* set window width `Ctrl+W [N columns]+(Shift+)<\>` + +___ + +##### Tool: [tail](https://en.wikipedia.org/wiki/Tail_(Unix)) + +###### Annotate tail -f with timestamps + +```bash +tail -f file | while read ; do echo "$(date +%T.%N) $REPLY" ; done +``` + +###### Analyse an Apache access log for the most common IP addresses + +```bash +tail -10000 access_log | awk '{print $1}' | sort | uniq -c | sort -n | tail +``` + +###### Analyse web server log and show only 5xx http codes + +```bash +tail -n 100 -f /path/to/logfile | grep "HTTP/[1-2].[0-1]\" [5]" +``` + +___ + +##### Tool: [tar](https://en.wikipedia.org/wiki/Tar_(computing)) + +###### System backup with exclude specific directories + +```bash +cd / +tar -czvpf /mnt/system$(date +%d%m%Y%s).tgz --directory=/ \ +--exclude=proc/* --exclude=sys/* --exclude=dev/* --exclude=mnt/* . +``` + +###### System backup with exclude specific directories (pigz) + +```bash +cd / +tar cvpf /backup/snapshot-$(date +%d%m%Y%s).tgz --directory=/ \ +--exclude=proc/* --exclude=sys/* --exclude=dev/* \ +--exclude=mnt/* --exclude=tmp/* --use-compress-program=pigz . +``` + +___ + +##### Tool: [dump](https://en.wikipedia.org/wiki/Dump_(program)) + +###### System backup to file + +```bash +dump -y -u -f /backup/system$(date +%d%m%Y%s).lzo / +``` + +###### Restore system from lzo file + +```bash +cd / +restore -rf /backup/system$(date +%d%m%Y%s).lzo +``` + +___ + +##### Tool: [tr](https://en.wikipedia.org/wiki/Tr_(Unix)) + +###### Show directories in the PATH, one per line + +```bash +tr : '\n' <<<$PATH +``` + +___ + +##### Tool: [chmod](https://en.wikipedia.org/wiki/Chmod) + +###### Remove executable bit from all files in the current directory + +```bash +chmod -R -x+X * +``` + +###### Restore permission for /bin/chmod + +```bash +# 1: +cp /bin/ls chmod.01 +cp /bin/chmod chmod.01 +./chmod.01 700 file + +# 2: +/bin/busybox chmod 0700 /bin/chmod + +# 3: +setfacl --set u::rwx,g::---,o::--- /bin/chmod +``` + +___ + +##### Tool: [who](https://en.wikipedia.org/wiki/Who_(Unix)) + +###### Find last reboot time + +```bash +who -b +``` + +###### Detect a user sudo-su'd into the current shell + +```bash +[[ $(who -m | awk '{ print $1 }') == $(whoami) ]] || echo "You are su-ed to $(whoami)" +``` + +___ + +##### Tool: [last](https://www.howtoforge.com/linux-last-command/) + +###### Was the last reboot a panic? + +```bash +(last -x -f $(ls -1t /var/log/wtmp* | head -2 | tail -1); last -x -f /var/log/wtmp) | \ +grep -A1 reboot | head -2 | grep -q shutdown && echo "Expected reboot" || echo "Panic reboot" +``` + +___ + +##### Tool: [screen](https://en.wikipedia.org/wiki/GNU_Screen) + +###### Start screen in detached mode + +```bash +screen -d -m +``` + +###### Attach to an existing screen session + +```bash +screen -r -d +``` + +___ + +##### Tool: [script](https://en.wikipedia.org/wiki/Script_(Unix)) + +###### Record and replay terminal session + +```bash +### Record session +# 1) +script -t 2>~/session.time -a ~/session.log + +# 2) +script --timing=session.time session.log + +### Replay session +scriptreplay --timing=session.time session.log +``` + +___ + +##### Tool: [du](https://en.wikipedia.org/wiki/GNU_Screen) + +###### Show 20 biggest directories with 'K M G' + +```bash +du | \ +sort -r -n | \ +awk '{split("K M G",v); s=1; while($1>1024){$1/=1024; s++} print int($1)" "v[s]"\t"$2}' | \ +head -n 20 +``` + +___ + +##### Tool: [inotifywait](https://en.wikipedia.org/wiki/GNU_Screen) + +###### Init tool everytime a file in a directory is modified + +```bash +while true ; do inotifywait -r -e MODIFY dir/ && ls dir/ ; done; +``` + +___ + +##### Tool: [openssl](https://www.openssl.org/) + +###### Testing connection to the remote host + +```bash +echo | openssl s_client -connect google.com:443 -showcerts +``` + +###### Testing connection to the remote host (debug mode) + +```bash +echo | openssl s_client -connect google.com:443 -showcerts -tlsextdebug -status +``` + +###### Testing connection to the remote host (with SNI support) + +```bash +echo | openssl s_client -showcerts -servername google.com -connect google.com:443 +``` + +###### Testing connection to the remote host with specific ssl version + +```bash +openssl s_client -tls1_2 -connect google.com:443 +``` + +###### Testing connection to the remote host with specific ssl cipher + +```bash +openssl s_client -cipher 'AES128-SHA' -connect google.com:443 +``` + +###### Verify 0-RTT + +```bash +_host="example.com" + +cat > req.in << __EOF__ +HEAD / HTTP/1.1 +Host: $_host +Connection: close +__EOF__ + +openssl s_client -connect ${_host}:443 -tls1_3 -sess_out session.pem -ign_eof < req.in +openssl s_client -connect ${_host}:443 -tls1_3 -sess_in session.pem -early_data req.in +``` + +###### Generate private key without passphrase + +```bash +# _len: 2048, 4096 +( _fd="private.key" ; _len="2048" ; \ +openssl genrsa -out ${_fd} ${_len} ) +``` + +###### Generate private key with passphrase + +```bash +# _ciph: aes128, aes256 +# _len: 2048, 4096 +( _ciph="aes128" ; _fd="private.key" ; _len="2048" ; \ +openssl genrsa -${_ciph} -out ${_fd} ${_len} ) +``` + +###### Remove passphrase from private key + +```bash +( _fd="private.key" ; _fd_unp="private_unp.key" ; \ +openssl rsa -in ${_fd} -out ${_fd_unp} ) +``` + +###### Encrypt existing private key with a passphrase + +```bash +# _ciph: aes128, aes256 +( _ciph="aes128" ; _fd="private.key" ; _fd_pass="private_pass.key" ; \ +openssl rsa -${_ciph} -in ${_fd} -out ${_fd_pass} +``` + +###### Check private key + +```bash +( _fd="private.key" ; \ +openssl rsa -check -in ${_fd} ) +``` + +###### Get public key from private key + +```bash +( _fd="private.key" ; _fd_pub="public.key" ; \ +openssl rsa -pubout -in ${_fd} -out ${_fd_pub} ) +``` + +###### Generate private key and CSR + +```bash +( _fd="private.key" ; _fd_csr="request.csr" ; _len="2048" ; \ +openssl req -out ${_fd_csr} -new -newkey rsa:${_len} -nodes -keyout ${_fd} ) +``` + +###### Generate CSR + +```bash +( _fd="private.key" ; _fd_csr="request.csr" ; \ +openssl req -out ${_fd_csr} -new -key ${_fd} ) +``` + +###### Generate CSR (metadata from existing certificate) + + > Where `private.key` is the existing private key. As you can see you do not generate this CSR from your certificate (public key). Also you do not generate the "same" CSR, just a new one to request a new certificate. + +```bash +( _fd="private.key" ; _fd_csr="request.csr" ; _fd_crt="cert.crt" ; \ +openssl x509 -x509toreq -in ${_fd_crt} -out ${_fd_csr} -signkey ${_fd} ) +``` + +###### Generate CSR with -config param + +```bash +( _fd="private.key" ; _fd_csr="request.csr" ; \ +openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \ +-config <( +cat << __EOF__ +[req] +default_bits = 2048 +default_md = sha256 +prompt = no +distinguished_name = dn +req_extensions = req_ext + +[ dn ] +C = "" +ST = "" +L = "" +O = "" +OU = "
" +CN = "" + +[ req_ext ] +subjectAltName = @alt_names + +[ alt_names ] +DNS.1 = +DNS.2 = +DNS.3 = +__EOF__ +)) +``` + +Other values in `[ dn ]`: + +``` +countryName = "DE" # C= +stateOrProvinceName = "Hessen" # ST= +localityName = "Keller" # L= +postalCode = "424242" # L/postalcode= +postalAddress = "Keller" # L/postaladdress= +streetAddress = "Crater 1621" # L/street= +organizationName = "apfelboymschule" # O= +organizationalUnitName = "IT Department" # OU= +commonName = "example.com" # CN= +emailAddress = "webmaster@example.com" # CN/emailAddress= +``` + +Example of `oids` (you'll probably also have to make OpenSSL know about the new fields required for EV by adding the following under `[new_oids]`): + +``` +[req] +... +oid_section = new_oids + +[ new_oids ] +postalCode = 2.5.4.17 +streetAddress = 2.5.4.9 +``` + +Full example: + +```bash +( _fd="private.key" ; _fd_csr="request.csr" ; \ +openssl req -new -sha256 -key ${_fd} -out ${_fd_csr} \ +-config <( +cat << __EOF__ +[req] +default_bits = 2048 +default_md = sha256 +prompt = no +distinguished_name = dn +req_extensions = req_ext +oid_section = new_oids + +[ new_oids ] +serialNumber = 2.5.4.5 +streetAddress = 2.5.4.9 +postalCode = 2.5.4.17 +businessCategory = 2.5.4.15 + +[ dn ] +serialNumber=00001111 +businessCategory=Private Organization +jurisdictionC=DE +C=DE +ST=Hessen +L=Keller +postalCode=424242 +streetAddress=Crater 1621 +O=AV Company +OU=IT +CN=example.com + +[ req_ext ] +subjectAltName = @alt_names + +[ alt_names ] +DNS.1 = example.com +__EOF__ +)) +``` + +For more information please look at these great explanations: + +- [RFC 5280](https://tools.ietf.org/html/rfc5280) +- [Generate a multi domains certificate using config files](https://gist.github.com/romainnorberg/464758a6620228b977212a3cf20c3e08) +- [Your OpenSSL CSR command is out of date](https://expeditedsecurity.com/blog/openssl-csr-command/) +- [OpenSSL example configuration file](https://www.tbs-certificats.com/openssl-dem-server-cert.cnf) +- [Object Identifiers (OIDs)](https://www.alvestrand.no/objectid/) +- [openssl objects.txt](https://github.com/openssl/openssl/blob/master/crypto/objects/objects.txt) + +###### List available EC curves + +```bash +openssl ecparam -list_curves +``` + +###### Print ECDSA private and public keys + +```bash +( _fd="private.key" ; \ +openssl ec -in ${_fd} -noout -text ) + +# For x25519 only extracting public key +( _fd="private.key" ; _fd_pub="public.key" ; \ +openssl pkey -in ${_fd} -pubout -out ${_fd_pub} ) +``` + +###### Generate ECDSA private key + +```bash +# _curve: prime256v1, secp521r1, secp384r1 +( _fd="private.key" ; _curve="prime256v1" ; \ +openssl ecparam -out ${_fd} -name ${_curve} -genkey ) + +# _curve: X25519 +( _fd="private.key" ; _curve="x25519" ; \ +openssl genpkey -algorithm ${_curve} -out ${_fd} ) +``` + +###### Generate private key and CSR (ECC) + +```bash +# _curve: prime256v1, secp521r1, secp384r1 +( _fd="domain.com.key" ; _fd_csr="domain.com.csr" ; _curve="prime256v1" ; \ +openssl ecparam -out ${_fd} -name ${_curve} -genkey ; \ +openssl req -new -key ${_fd} -out ${_fd_csr} -sha256 ) +``` + +###### Generate self-signed certificate + +```bash +# _len: 2048, 4096 +( _fd="domain.key" ; _fd_out="domain.crt" ; _len="2048" ; _days="365" ; \ +openssl req -newkey rsa:${_len} -nodes \ +-keyout ${_fd} -x509 -days ${_days} -out ${_fd_out} ) +``` + +###### Generate self-signed certificate from existing private key + +```bash +# _len: 2048, 4096 +( _fd="domain.key" ; _fd_out="domain.crt" ; _days="365" ; \ +openssl req -key ${_fd} -nodes \ +-x509 -days ${_days} -out ${_fd_out} ) +``` + +###### Generate self-signed certificate from existing private key and csr + +```bash +# _len: 2048, 4096 +( _fd="domain.key" ; _fd_csr="domain.csr" ; _fd_out="domain.crt" ; _days="365" ; \ +openssl x509 -signkey ${_fd} -nodes \ +-in ${_fd_csr} -req -days ${_days} -out ${_fd_out} ) +``` + +###### Generate DH public parameters + +```bash +( _dh_size="2048" ; \ +openssl dhparam -out /etc/nginx/ssl/dhparam_${_dh_size}.pem "$_dh_size" ) +``` + +###### Display DH public parameters + +```bash +openssl pkeyparam -in dhparam.pem -text +``` + +###### Extract private key from pfx + +```bash +( _fd_pfx="cert.pfx" ; _fd_key="key.pem" ; \ +openssl pkcs12 -in ${_fd_pfx} -nocerts -nodes -out ${_fd_key} ) +``` + +###### Extract private key and certs from pfx + +```bash +( _fd_pfx="cert.pfx" ; _fd_pem="key_certs.pem" ; \ +openssl pkcs12 -in ${_fd_pfx} -nodes -out ${_fd_pem} ) +``` + +###### Extract certs from p7b + +```bash +# PKCS#7 file doesn't include private keys. +( _fd_p7b="cert.p7b" ; _fd_pem="cert.pem" ; \ +openssl pkcs7 -inform DER -outform PEM -in ${_fd_p7b} -print_certs > ${_fd_pem}) +# or: +openssl pkcs7 -print_certs -in -in ${_fd_p7b} -out ${_fd_pem}) +``` + +###### Convert DER to PEM + +```bash +( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \ +openssl x509 -in ${_fd_der} -inform der -outform pem -out ${_fd_pem} ) +``` + +###### Convert PEM to DER + +```bash +( _fd_der="cert.crt" ; _fd_pem="cert.pem" ; \ +openssl x509 -in ${_fd_pem} -outform der -out ${_fd_der} ) +``` + +###### Verification of the private key + +```bash +( _fd="private.key" ; \ +openssl rsa -noout -text -in ${_fd} ) +``` + +###### Verification of the public key + +```bash +# 1) +( _fd="public.key" ; \ +openssl pkey -noout -text -pubin -in ${_fd} ) + +# 2) +( _fd="private.key" ; \ +openssl rsa -inform PEM -noout -in ${_fd} &> /dev/null ; \ +if [ $? = 0 ] ; then echo -en "OK\n" ; fi ) +``` + +###### Verification of the certificate + +```bash +( _fd="certificate.crt" ; # format: pem, cer, crt \ +openssl x509 -noout -text -in ${_fd} ) +``` + +###### Verification of the CSR + +```bash +( _fd_csr="request.csr" ; \ +openssl req -text -noout -in ${_fd_csr} ) +``` + +###### Check the private key and the certificate are match + +```bash +(openssl rsa -noout -modulus -in private.key | openssl md5 ; \ +openssl x509 -noout -modulus -in certificate.crt | openssl md5) | uniq +``` + +###### Check the private key and the CSR are match + +```bash +(openssl rsa -noout -modulus -in private.key | openssl md5 ; \ +openssl req -noout -modulus -in request.csr | openssl md5) | uniq +``` + +___ + +##### Tool: [secure-delete](https://wiki.archlinux.org/index.php/Securely_wipe_disk) + +###### Secure delete with shred + +```bash +shred -vfuz -n 10 file +shred --verbose --random-source=/dev/urandom -n 1 /dev/sda +``` + +###### Secure delete with scrub + +```bash +scrub -p dod /dev/sda +scrub -p dod -r file +``` + +###### Secure delete with badblocks + +```bash +badblocks -s -w -t random -v /dev/sda +badblocks -c 10240 -s -w -t random -v /dev/sda +``` + +###### Secure delete with secure-delete + +```bash +srm -vz /tmp/file +sfill -vz /local +sdmem -v +swapoff /dev/sda5 && sswap -vz /dev/sda5 +``` + +___ + +##### Tool: [dd](https://en.wikipedia.org/wiki/Dd_(Unix)) + +###### Show dd status every so often + +```bash +dd status=progress +watch --interval 5 killall -USR1 dd +``` + +###### Redirect output to a file with dd + +```bash +echo "string" | dd of=filename +``` + +___ + +##### Tool: [gpg](https://www.gnupg.org/) + +###### Export public key + +```bash +gpg --export --armor "" > username.pkey +``` + + * `--export` - export all keys from all keyrings or specific key + * `-a|--armor` - create ASCII armored output + +###### Encrypt file + +```bash +gpg -e -r "" dump.sql +``` + + * `-e|--encrypt` - encrypt data + * `-r|--recipient` - encrypt for specific + +###### Decrypt file + +```bash +gpg -o dump.sql -d dump.sql.gpg +``` + + * `-o|--output` - use as output file + * `-d|--decrypt` - decrypt data (default) + +###### Search recipient + +```bash +gpg --keyserver hkp://keyserver.ubuntu.com --search-keys "" +``` + + * `--keyserver` - set specific key server + * `--search-keys` - search for keys on a key server + +###### List all of the packets in an encrypted file + +```bash +gpg --batch --list-packets archive.gpg +gpg2 --batch --list-packets archive.gpg +``` + +___ + +##### Tool: [system-other](https://github.com/trimstray/the-book-of-secret-knowledge#tool-system-other) + +###### Reboot system from init + +```bash +exec /sbin/init 6 +``` + +###### Init system from single user mode + +```bash +exec /sbin/init +``` + +###### Show current working directory of a process + +```bash +readlink -f /proc//cwd +``` + +###### Show actual pathname of the executed command + +```bash +readlink -f /proc//exe +``` + +##### Tool: [curl](https://curl.haxx.se) + +```bash +curl -Iks https://www.google.com +``` + + * `-I` - show response headers only + * `-k` - insecure connection when using ssl + * `-s` - silent mode (not display body) + +```bash +curl -Iks --location -X GET -A "x-agent" https://www.google.com +``` + + * `--location` - follow redirects + * `-X` - set method + * `-A` - set user-agent + +```bash +curl -Iks --location -X GET -A "x-agent" --proxy http://127.0.0.1:16379 https://www.google.com +``` + + * `--proxy [socks5://|http://]` - set proxy server + +```bash +curl -o file.pdf -C - https://example.com/Aiju2goo0Ja2.pdf +``` + + * `-o` - write output to file + * `-C` - resume the transfer + +###### Find your external IP address (external services) + +```bash +curl ipinfo.io +curl ipinfo.io/ip +curl icanhazip.com +curl ifconfig.me/ip ; echo +``` + +###### Repeat URL request + +```bash +# URL sequence substitution with a dummy query string: +curl -ks https://example.com/?[1-20] + +# With shell 'for' loop: +for i in {1..20} ; do curl -ks https://example.com/ ; done +``` + +###### Check DNS and HTTP trace with headers for specific domains + +```bash +### Set domains and external dns servers. +_domain_list=(google.com) ; _dns_list=("8.8.8.8" "1.1.1.1") + +for _domain in "${_domain_list[@]}" ; do + + printf '=%.0s' {1..48} + + echo + + printf "[\\e[1;32m+\\e[m] resolve: %s\\n" "$_domain" + + for _dns in "${_dns_list[@]}" ; do + + # Resolve domain. + host "${_domain}" "${_dns}" + + echo + + done + + for _proto in http https ; do + + printf "[\\e[1;32m+\\e[m] trace + headers: %s://%s\\n" "$_proto" "$_domain" + + # Get trace and http headers. + curl -Iks -A "x-agent" --location "${_proto}://${_domain}" + + echo + + done + +done + +unset _domain_list _dns_list +``` + +___ + +##### Tool: [httpie](https://httpie.org/) + +```bash +http -p Hh https://www.google.com +``` + + * `-p` - print request and response headers + * `H` - request headers + * `B` - request body + * `h` - response headers + * `b` - response body + +```bash +http -p Hh https://www.google.com --follow --verify no +``` + + * `-F, --follow` - follow redirects + * `--verify no` - skip SSL verification + +```bash +http -p Hh https://www.google.com --follow --verify no \ +--proxy http:http://127.0.0.1:16379 +``` + + * `--proxy [http:]` - set proxy server + +##### Tool: [ssh](https://www.openssh.com/) + +###### Escape Sequence + +``` +# Supported escape sequences: +~. - terminate connection (and any multiplexed sessions) +~B - send a BREAK to the remote system +~C - open a command line +~R - Request rekey (SSH protocol 2 only) +~^Z - suspend ssh +~# - list forwarded connections +~& - background ssh (when waiting for connections to terminate) +~? - this message +~~ - send the escape character by typing it twice +``` + +###### Compare a remote file with a local file + +```bash +ssh user@host cat /path/to/remotefile | diff /path/to/localfile - +``` + +###### SSH connection through host in the middle + +```bash +ssh -t reachable_host ssh unreachable_host +``` + +###### Run command over SSH on remote host + +```bash +cat > cmd.txt << __EOF__ +cat /etc/hosts +__EOF__ + +ssh host -l user $(&1 | tee -a "${_sesdir}/$(date +%Y%m%d).log" + +} + +# Alias: +alias ssh='_ssh_sesslog' +``` + +###### Using Keychain for SSH logins + +```bash +### Delete all of ssh-agent's keys. +function _scl() { + + /usr/bin/keychain --clear + +} + +### Add key to keychain. +function _scg() { + + /usr/bin/keychain /path/to/private-key + source "$HOME/.keychain/$HOSTNAME-sh" + +} +``` + +###### SSH login without processing any login scripts + +```bash +ssh -tt user@host bash +``` + +###### SSH local port forwarding + +Example 1: + +```bash +# Forwarding our local 2250 port to nmap.org:443 from localhost through localhost +host1> ssh -L 2250:nmap.org:443 localhost + +# Connect to the service: +host1> curl -Iks --location -X GET https://localhost:2250 +``` + +Example 2: + +```bash +# Forwarding our local 9051 port to db.d.x:5432 from localhost through node.d.y +host1> ssh -nNT -L 9051:db.d.x:5432 node.d.y + +# Connect to the service: +host1> psql -U db_user -d db_dev -p 9051 -h localhost +``` + + * `-n` - redirects stdin from `/dev/null` + * `-N` - do not execute a remote command + * `-T` - disable pseudo-terminal allocation + +###### SSH remote port forwarding + +```bash +# Forwarding our local 9051 port to db.d.x:5432 from host2 through node.d.y +host1> ssh -nNT -R 9051:db.d.x:5432 node.d.y + +# Connect to the service: +host2> psql -U postgres -d postgres -p 8000 -h localhost +``` + +___ + +##### Tool: [linux-dev](https://www.tldp.org/LDP/abs/html/devref1.html) + +###### Testing remote connection to port + +```bash +timeout 1 bash -c "//" >/dev/null 2>&1 ; echo $? +``` + + * `` - set remote host + * `` - set destination port + +###### Read and write to TCP or UDP sockets with common bash tools + +```bash +exec 5<>/dev/tcp//; cat <&5 & cat >&5; exec 5>&- +``` + +___ + +##### Tool: [tcpdump](http://www.tcpdump.org/) + +###### Filter incoming (on interface) traffic (specific ) + +```bash +tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443 +``` + + * `-n` - don't convert addresses (`-nn` will not resolve hostnames or ports) + * `-e` - print the link-level headers + * `-i [iface|any]` - set interface + * `-Q|-D [in|out|inout]` - choose send/receive direction (`-D` - for old tcpdump versions) + * `host [ip|hostname]` - set host, also `[host not]` + * `[and|or]` - set logic + * `port [1-65535]` - set port number, also `[port not]` + +###### Filter incoming (on interface) traffic (specific ) and write to a file + +```bash +tcpdump -ne -i eth0 -Q in host 192.168.252.1 and port 443 -c 5 -w tcpdump.pcap +``` + + * `-c [num]` - capture only num number of packets + * `-w [filename]` - write packets to file, `-r [filename]` - reading from file + +###### Capture all ICMP packets + +```bash +tcpdump -nei eth0 icmp +``` + +###### Check protocol used (TCP or UDP) for service + +```bash +tcpdump -nei eth0 tcp port 22 -vv -X | egrep "TCP|UDP" +``` + +###### Display ASCII text (to parse the output using grep or other) + +```bash +tcpdump -i eth0 -A -s0 port 443 +``` + +###### Grab everything between two keywords + +```bash +tcpdump -i eth0 port 80 -X | sed -n -e '/username/,/=ldap/ p' +``` + +###### Grab user and pass ever plain http + +```bash +tcpdump -i eth0 port http -l -A | egrep -i \ +'pass=|pwd=|log=|login=|user=|username=|pw=|passw=|passwd=|password=|pass:|user:|username:|password:|login:|pass |user ' \ +--color=auto --line-buffered -B20 +``` + +###### Extract HTTP User Agent from HTTP request header + +```bash +tcpdump -ei eth0 -nn -A -s1500 -l | grep "User-Agent:" +``` + +###### Capture only HTTP GET and POST packets + +```bash +tcpdump -ei eth0 -s 0 -A -vv \ +'tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x47455420' or 'tcp[((tcp[12:1] & 0xf0) >> 2):4] = 0x504f5354' +``` + +or simply: + +```bash +tcpdump -ei eth0 -s 0 -v -n -l | egrep -i "POST /|GET /|Host:" +``` + +###### Rotate capture files + +```bash +tcpdump -ei eth0 -w /tmp/capture-%H.pcap -G 3600 -C 200 +``` + + * `-G ` - pcap will be created every `` seconds + * `-C ` - close the current pcap and open a new one if is larger than `` + +###### Top hosts by packets + +```bash +tcpdump -ei enp0s25 -nnn -t -c 200 | cut -f 1,2,3,4 -d '.' | sort | uniq -c | sort -nr | head -n 20 +``` + +###### Excludes any RFC 1918 private address + +```bash +tcpdump -nei eth0 'not (src net (10 or 172.16/12 or 192.168/16) and dst net (10 or 172.16/12 or 192.168/16))' +``` +___ + +##### Tool: [ngrep](https://github.com/jpr5/ngrep) + +```bash +ngrep -d eth0 "www.domain.com" port 443 +``` + + * `-d [iface|any]` - set interface + * `[domain]` - set hostname + * `port [1-65535]` - set port number + +```bash +ngrep -d eth0 "www.domain.com" src host 10.240.20.2 and port 443 +``` + + * `(host [ip|hostname])` - filter by ip or hostname + * `(port [1-65535])` - filter by port number + +```bash +ngrep -d eth0 -qt -O ngrep.pcap "www.domain.com" port 443 +``` + + * `-q` - quiet mode (only payloads) + * `-t` - added timestamps + * `-O [filename]` - save output to file, `-I [filename]` - reading from file + +```bash +ngrep -d eth0 -qt 'HTTP' 'tcp' +``` + + * `HTTP` - show http headers + * `tcp|udp` - set protocol + * `[src|dst] host [ip|hostname]` - set direction for specific node + +```bash +ngrep -l -q -d eth0 -i "User-Agent: curl*" +``` + + * `-l` - stdout line buffered + * `-i` - case-insensitive search + +___ + +##### Tool: [hping3](https://github.com/antirez/hping) + +```bash +hping3 -V -p 80 -s 5050 www.google.com +``` + + * `-V|--verbose` - verbose mode + * `-p|--destport` - set destination port + * `-s|--baseport` - set source port + * `` - set scan type + * `-F|--fin` - set FIN flag, port open if no reply + * `-S|--syn` - set SYN flag + * `-P|--push` - set PUSH flag + * `-A|--ack` - set ACK flag (use when ping is blocked, RST response back if the port is open) + * `-U|--urg` - set URG flag + * `-Y|--ymas` - set Y unused flag (0x80 - nullscan), port open if no reply + * `-M 0 -UPF` - set TCP sequence number and scan type (URG+PUSH+FIN), port open if no reply + +```bash +hping3 -V -c 1 -1 -C 8 www.google.com +``` + + * `-c [num]` - packet count + * `-1` - set ICMP mode + * `-C|--icmptype [icmp-num]` - set icmp type (default icmp-echo = 8) + +```bash +hping3 -V -c 1000000 -d 120 -S -w 64 -p 80 --flood --rand-source +``` + + * `--flood` - sent packets as fast as possible (don't show replies) + * `--rand-source` - random source address mode + * `-d --data` - data size + * `-w|--win` - winsize (default 64) + +___ + +##### Tool: [nmap](https://nmap.org/) + +###### Ping scans the network + +```bash +nmap -sP 192.168.0.0/24 +``` + +###### Show only open ports + +```bash +nmap -F --open 192.168.0.0/24 +``` + +###### Full TCP port scan using with service version detection + +```bash +nmap -p 1-65535 -sV -sS -T4 192.168.0.0/24 +``` + +###### Nmap scan and pass output to Nikto + +```bash +nmap -p80,443 192.168.0.0/24 -oG - | nikto.pl -h - +``` + +###### Recon specific ip:service with Nmap NSE scripts stack + +```bash +# Set variables: +_hosts="192.168.250.10" +_ports="80,443" + +# Set Nmap NSE scripts stack: +_nmap_nse_scripts="+dns-brute,\ + +http-auth-finder,\ + +http-chrono,\ + +http-cookie-flags,\ + +http-cors,\ + +http-cross-domain-policy,\ + +http-csrf,\ + +http-dombased-xss,\ + +http-enum,\ + +http-errors,\ + +http-git,\ + +http-grep,\ + +http-internal-ip-disclosure,\ + +http-jsonp-detection,\ + +http-malware-host,\ + +http-methods,\ + +http-passwd,\ + +http-phpself-xss,\ + +http-php-version,\ + +http-robots.txt,\ + +http-sitemap-generator,\ + +http-shellshock,\ + +http-stored-xss,\ + +http-title,\ + +http-unsafe-output-escaping,\ + +http-useragent-tester,\ + +http-vhosts,\ + +http-waf-detect,\ + +http-waf-fingerprint,\ + +http-xssed,\ + +traceroute-geolocation.nse,\ + +ssl-enum-ciphers,\ + +whois-domain,\ + +whois-ip" + +# Set Nmap NSE script params: +_nmap_nse_scripts_args="dns-brute.domain=${_hosts},http-cross-domain-policy.domain-lookup=true," +_nmap_nse_scripts_args+="http-waf-detect.aggro,http-waf-detect.detectBodyChanges," +_nmap_nse_scripts_args+="http-waf-fingerprint.intensive=1" + +# Perform scan: +nmap --script="$_nmap_nse_scripts" --script-args="$_nmap_nse_scripts_args" -p "$_ports" "$_hosts" +``` + +___ + +##### Tool: [netcat](https://en.wikipedia.org/wiki/Netcat) + +```bash +nc -kl 5000 +``` + + * `-l` - listen for an incoming connection + * `-k` - listening after client has disconnected + * `>filename.out` - save receive data to file (optional) + +```bash +nc 192.168.0.1 5051 < filename.in +``` + + * `< filename.in` - send data to remote host + +```bash +nc -vz 10.240.30.3 5000 +``` + + * `-v` - verbose output + * `-z` - scan for listening daemons + +```bash +nc -vzu 10.240.30.3 1-65535 +``` + + * `-u` - scan only udp ports + +###### Transfer data file (archive) + +```bash +server> nc -l 5000 | tar xzvfp - +client> tar czvfp - /path/to/dir | nc 10.240.30.3 5000 +``` + +###### Launch remote shell + +```bash +# 1) +server> nc -l 5000 -e /bin/bash +client> nc 10.240.30.3 5000 + +# 2) +server> rm -f /tmp/f; mkfifo /tmp/f +server> cat /tmp/f | /bin/bash -i 2>&1 | nc -l 127.0.0.1 5000 > /tmp/f +client> nc 10.240.30.3 5000 +``` + +###### Simple file server + +```bash +while true ; do nc -l 5000 | tar -xvf - ; done +``` + +###### Simple minimal HTTP Server + +```bash +while true ; do nc -l -p 1500 -c 'echo -e "HTTP/1.1 200 OK\n\n $(date)"' ; done +``` + +###### Simple HTTP Server + + > Restarts web server after each request - remove `while` condition for only single connection. + +```bash +cat > index.html << __EOF__ + + + + + + + + + + +

+ + Hello! It's a site. + +

+ + + +__EOF__ +``` + +```bash +server> while : ; do \ +(echo -ne "HTTP/1.1 200 OK\r\nContent-Length: $(wc -c /" <"$_sent" & +sed "s/^/<= /" <"$_recv" & + +nc -l -p "$_listen_port" <"$_back" | \ +tee "$_sent" | \ +nc "$_bk_host" "$_bk_port" | \ +tee "$_recv" >"$_back" +``` + +```bash +server> chmod +x nc-proxy && ./nc-proxy 8080 192.168.252.10:8000 + lport: 8080 +bk_host: 192.168.252.10 +bk_port: 8000 + +client> http -p h 10.240.30.3:8080 +HTTP/1.1 200 OK +Accept-Ranges: bytes +Cache-Control: max-age=31536000 +Content-Length: 2748 +Content-Type: text/html; charset=utf-8 +Date: Sun, 01 Jul 2018 20:12:08 GMT +Last-Modified: Sun, 01 Apr 2018 21:53:37 GMT +``` + +###### Create a single-use TCP or UDP proxy + +```bash +### TCP -> TCP +nc -l -p 2000 -c "nc [ip|hostname] 3000" + +### TCP -> UDP +nc -l -p 2000 -c "nc -u [ip|hostname] 3000" + +### UDP -> UDP +nc -l -u -p 2000 -c "nc -u [ip|hostname] 3000" + +### UDP -> TCP +nc -l -u -p 2000 -c "nc [ip|hostname] 3000" +``` + +___ + +##### Tool: [gnutls-cli](https://gnutls.org/manual/html_node/gnutls_002dcli-Invocation.html) + +###### Testing connection to remote host (with SNI support) + +```bash +gnutls-cli -p 443 google.com +``` + +###### Testing connection to remote host (without SNI support) + +```bash +gnutls-cli --disable-sni -p 443 google.com +``` + +___ + +##### Tool: [socat](http://www.dest-unreach.org/socat/doc/socat.html) + +###### Testing remote connection to port + +```bash +socat - TCP4:10.240.30.3:22 +``` + + * `-` - standard input (STDIO) + * `TCP4:` - set tcp4 connection with specific params + * `[hostname|ip]` - set hostname/ip + * `[1-65535]` - set port number + +###### Redirecting TCP-traffic to a UNIX domain socket under Linux + +```bash +socat TCP-LISTEN:1234,bind=127.0.0.1,reuseaddr,fork,su=nobody,range=127.0.0.0/8 UNIX-CLIENT:/tmp/foo +``` + + * `TCP-LISTEN:` - set tcp listen with specific params + * `[1-65535]` - set port number + * `bind=[hostname|ip]` - set bind hostname/ip + * `reuseaddr` - allows other sockets to bind to an address + * `fork` - keeps the parent process attempting to produce more connections + * `su=nobody` - set user + * `range=[ip-range]` - ip range + * `UNIX-CLIENT:` - communicates with the specified peer socket + * `filename` - define socket + +___ + +##### Tool: [p0f](http://lcamtuf.coredump.cx/p0f3/) + +###### Set iface in promiscuous mode and dump traffic to the log file + +```bash +p0f -i enp0s25 -p -d -o /dump/enp0s25.log +``` + + * `-i` - listen on the specified interface + * `-p` - set interface in promiscuous mode + * `-d` - fork into background + * `-o` - output file + +___ + +##### Tool: [netstat](https://en.wikipedia.org/wiki/Netstat) + +###### Graph # of connections for each hosts + +```bash +netstat -an | awk '/ESTABLISHED/ { split($5,ip,":"); if (ip[1] !~ /^$/) print ip[1] }' | \ +sort | uniq -c | awk '{ printf("%s\t%s\t",$2,$1) ; for (i = 0; i < $1; i++) {printf("*")}; print "" }' +``` + +###### Monitor open connections for specific port including listen, count and sort it per IP + +```bash +watch "netstat -plan | grep :443 | awk {'print \$5'} | cut -d: -f 1 | sort | uniq -c | sort -nk 1" +``` + +###### Grab banners from local IPv4 listening ports + +```bash +netstat -nlt | grep 'tcp ' | grep -Eo "[1-9][0-9]*" | xargs -I {} sh -c "echo "" | nc -v -n -w1 127.0.0.1 {}" +``` + +___ + +##### Tool: [rsync](https://en.wikipedia.org/wiki/Rsync) + +###### Rsync remote data as root using sudo + +```bash +rsync --rsync-path 'sudo rsync' username@hostname:/path/to/dir/ /local/ +``` + +___ + +##### Tool: [host](https://en.wikipedia.org/wiki/Host_(Unix)) + +###### Resolves the domain name (using external dns server) + +```bash +host google.com 9.9.9.9 +``` + +###### Checks the domain administrator (SOA record) + +```bash +host -t soa google.com 9.9.9.9 +``` + +___ + +##### Tool: [dig](https://en.wikipedia.org/wiki/Dig_(command)) + +###### Resolves the domain name (short output) + +```bash +dig google.com +short +``` + +###### Lookup NS record for specific domain + +```bash +dig @9.9.9.9 google.com NS +``` + +###### Query only answer section + +```bash +dig google.com +nocomments +noquestion +noauthority +noadditional +nostats +``` + +###### Query ALL DNS Records + +```bash +dig google.com ANY +noall +answer +``` + +###### DNS Reverse Look-up + +```bash +dig -x 172.217.16.14 +short +``` + +___ + +##### Tool: [certbot](https://certbot.eff.org/) + +###### Generate multidomain certificate + +```bash +certbot certonly -d example.com -d www.example.com +``` + +###### Generate wildcard certificate + +```bash +certbot certonly --manual --preferred-challenges=dns -d example.com -d *.example.com +``` + +###### Generate certificate with 4096 bit private key + +```bash +certbot certonly -d example.com -d www.example.com --rsa-key-size 4096 +``` + +___ + +##### Tool: [network-other](https://github.com/trimstray/the-book-of-secret-knowledge#tool-network-other) + +###### Get all subnets for specific AS (Autonomous system) + +```bash +AS="AS32934" +whois -h whois.radb.net -- "-i origin ${AS}" | \ +grep "^route:" | \ +cut -d ":" -f2 | \ +sed -e 's/^[ \t]//' | \ +sort -n -t . -k 1,1 -k 2,2 -k 3,3 -k 4,4 | \ +cut -d ":" -f2 | \ +sed -e 's/^[ \t]/allow /' | \ +sed 's/$/;/' | \ +sed 's/allow */subnet -> /g' +``` + +###### Resolves domain name from dns.google.com with curl and jq + +```bash +_dname="google.com" ; curl -s "https://dns.google.com/resolve?name=${_dname}&type=A" | jq . +``` + +##### Tool: [git](https://git-scm.com/) + +###### Log alias for a decent view of your repo + +```bash +# 1) +git log --oneline --decorate --graph --all + +# 2) +git log --graph \ +--pretty=format:'%Cred%h%Creset -%C(yellow)%d%Creset %s %Cgreen(%cr) %C(bold blue)<%an>%Creset' \ +--abbrev-commit +``` + +___ + +##### Tool: [python](https://www.python.org/) + +###### Static HTTP web server + +```bash +# Python 3.x +python3 -m http.server 8000 --bind 127.0.0.1 + +# Python 2.x +python -m SimpleHTTPServer 8000 +``` + +###### Static HTTP web server with SSL support + +```bash +# Python 3.x +from http.server import HTTPServer, BaseHTTPRequestHandler +import ssl + +httpd = HTTPServer(('localhost', 4443), BaseHTTPRequestHandler) + +httpd.socket = ssl.wrap_socket (httpd.socket, + keyfile="path/to/key.pem", + certfile='path/to/cert.pem', server_side=True) + +httpd.serve_forever() + +# Python 2.x +import BaseHTTPServer, SimpleHTTPServer +import ssl + +httpd = BaseHTTPServer.HTTPServer(('localhost', 4443), + SimpleHTTPServer.SimpleHTTPRequestHandler) + +httpd.socket = ssl.wrap_socket (httpd.socket, + keyfile="path/tp/key.pem", + certfile='path/to/cert.pem', server_side=True) + +httpd.serve_forever() +``` + +###### Encode base64 + +```bash +python -m base64 -e <<< "sample string" +``` + +###### Decode base64 + +```bash +python -m base64 -d <<< "dGhpcyBpcyBlbmNvZGVkCg==" +``` + +##### Tool: [awk](http://www.grymoire.com/Unix/Awk.html) + +###### Search for matching lines + +```bash +# egrep foo +awk '/foo/' filename +``` + +###### Search non matching lines + +```bash +# egrep -v foo +awk '!/foo/' filename +``` + +###### Print matching lines with numbers + +```bash +# egrep -n foo +awk '/foo/{print FNR,$0}' filename +``` + +###### Print the last column + +```bash +awk '{print $NF}' filename +``` + +###### Find all the lines longer than 80 characters + +```bash +awk 'length($0)>80{print FNR,$0}' filename +``` + +###### Print only lines of less than 80 characters + +```bash +awk 'length < 80' filename +``` + +###### Print double new lines a file + +```bash +awk '1; { print "" }' filename +``` + +###### Print line numbers + +```bash +awk '{ print FNR "\t" $0 }' filename +awk '{ printf("%5d : %s\n", NR, $0) }' filename # in a fancy manner +``` + +###### Print line numbers for only non-blank lines + +```bash +awk 'NF { $0=++a " :" $0 }; { print }' filename +``` + +###### Print the line and the next two (i=5) lines after the line matching regexp + +```bash +awk '/foo/{i=5+1;}{if(i){i--; print;}}' filename +``` + +###### Print the lines starting at the line matching 'server {' until the line matching '}' + +```bash +awk '/server {/,/}/' filename +``` + +###### Print multiple columns with separators + +```bash +awk -F' ' '{print "ip:\t" $2 "\n port:\t" $3' filename +``` + +###### Remove empty lines + +```bash +awk 'NF > 0' filename + +# alternative: +awk NF filename +``` + +###### Delete trailing white space (spaces, tabs) + +```bash +awk '{sub(/[ \t]*$/, "");print}' filename +``` + +###### Delete leading white space + +```bash +awk '{sub(/^[ \t]+/, ""); print}' filename +``` + +###### Remove duplicate consecutive lines + +```bash +# uniq +awk 'a !~ $0{print}; {a=$0}' filename +``` + +###### Remove duplicate entries in a file without sorting + +```bash +awk '!x[$0]++' filename +``` + +###### Exclude multiple columns + +```bash +awk '{$1=$3=""}1' filename +``` + +###### Substitute foo for bar on lines matching regexp + +```bash +awk '/regexp/{gsub(/foo/, "bar")};{print}' filename +``` + +###### Add some characters at the beginning of matching lines + +```bash +awk '/regexp/{sub(/^/, "++++"); print;next;}{print}' filename +``` + +###### Get the last hour of Apache logs + +```bash +awk '/'$(date -d "1 hours ago" "+%d\\/%b\\/%Y:%H:%M")'/,/'$(date "+%d\\/%b\\/%Y:%H:%M")'/ { print $0 }' \ +/var/log/httpd/access_log +``` + +___ + +##### Tool: [sed](http://www.grymoire.com/Unix/Sed.html) + +###### Print a specific line from a file + +```bash +sed -n 10p /path/to/file +``` + +###### Remove a specific line from a file + +```bash +sed -i 10d /path/to/file +# alternative (BSD): sed -i'' 10d /path/to/file +``` + +###### Remove a range of lines from a file + +```bash +sed -i -re ',d' +``` + +###### Replace newline(s) with a space + +```bash +sed ':a;N;$!ba;s/\n/ /g' /path/to/file + +# cross-platform compatible syntax: +sed -e ':a' -e 'N' -e '$!ba' -e 's/\n/ /g' /path/to/file +``` + +- `:a` create a label `a` +- `N` append the next line to the pattern space +- `$!` if not the last line, ba branch (go to) label `a` +- `s` substitute, `/\n/` regex for new line, `/ /` by a space, `/g` global match (as many times as it can) + +Alternatives: + +```bash +# perl version (sed-like speed): +perl -p -e 's/\n/ /' /path/to/file + +# bash version (slow): +while read line ; do printf "%s" "$line " ; done < file +``` + +###### Delete string +N next lines + +```bash +sed '/start/,+4d' /path/to/file +``` + +___ + +##### Tool: [grep](http://www.grymoire.com/Unix/Grep.html) + +###### Search for a "pattern" inside all files in the current directory + +```bash +grep -rn "pattern" +grep -RnisI "pattern" * +fgrep "pattern" * -R +``` + +###### Show only for multiple patterns + +```bash +grep 'INFO*'\''WARN' filename +grep 'INFO\|WARN' filename +grep -e INFO -e WARN filename +grep -E '(INFO|WARN)' filename +egrep "INFO|WARN" filename +``` + +###### Except multiple patterns + +```bash +grep -vE '(error|critical|warning)' filename +``` + +###### Show data from file without comments + +```bash +grep -v ^[[:space:]]*# filename +``` + +###### Show data from file without comments and new lines + +```bash +egrep -v '#|^$' filename +``` + +###### Show strings with a dash/hyphen + +```bash +grep -e -- filename +grep -- -- filename +grep "\-\-" filename +``` + +###### Remove blank lines from a file and save output to new file + +```bash +grep . filename > newfilename +``` + +##### Tool: [perl](https://www.perl.org/) + +###### Search and replace (in place) + +```bash +perl -i -pe's/SEARCH/REPLACE/' filename +``` + +###### Edit of `*.conf` files changing all foo to bar (and backup original) + +```bash +perl -p -i.orig -e 's/\bfoo\b/bar/g' *.conf +``` + +###### Prints the first 20 lines from `*.conf` files + +```bash +perl -pe 'exit if $. > 20' *.conf +``` + +###### Search lines 10 to 20 + +```bash +perl -ne 'print if 10 .. 20' filename +``` + +###### Delete first 10 lines (and backup original) + +```bash +perl -i.orig -ne 'print unless 1 .. 10' filename +``` + +###### Delete all but lines between foo and bar (and backup original) + +```bash +perl -i.orig -ne 'print unless /^foo$/ .. /^bar$/' filename +``` + +###### Reduce multiple blank lines to a single line + +```bash +perl -p -i -00pe0 filename +``` + +###### Convert tabs to spaces (1t = 2sp) + +```bash +perl -p -i -e 's/\t/ /g' filename +``` + +###### Read input from a file and report number of lines and characters + +```bash +perl -lne '$i++; $in += length($_); END { print "$i lines, $in characters"; }' filename +``` + +#### Shell Tricks  [[TOC]](#anger-table-of-contents) + +When you get a shell, it is generally not very clean, but after following these steps, you will have a fairly clean and comfortable shell to work with. + +1) `script /dev/null -c bash` +2) Ctrl-Z (to send it to background) +3) `stty raw -echo; fg` (returns the shell to foreground) +4) `reset` (to reset terminal) +5) `xterm` (when asked for terminal type) +6) `export TERM=xterm; export SHELL=bash` + +#### Shell functions  [[TOC]](#anger-table-of-contents) + +##### Table of Contents + +- [Domain resolve](#domain-resolve) +- [Get ASN](#get-asn) + +###### Domain resolve + +```bash +# Dependencies: +# - curl +# - jq + +function DomainResolve() { + + local _host="$1" + + local _curl_base="curl --request GET" + local _timeout="15" + + _host_ip=$($_curl_base -ks -m "$_timeout" "https://dns.google.com/resolve?name=${_host}&type=A" | \ + jq '.Answer[0].data' | tr -d "\"" 2>/dev/null) + + if [[ -z "$_host_ip" ]] || [[ "$_host_ip" == "null" ]] ; then + + echo -en "Unsuccessful domain name resolution.\\n" + + else + + echo -en "$_host > $_host_ip\\n" + + fi + +} +``` + +Example: + +```bash +shell> DomainResolve nmap.org +nmap.org > 45.33.49.119 + +shell> DomainResolve nmap.org +Unsuccessful domain name resolution. +``` + +###### Get ASN + +```bash +# Dependencies: +# - curl + +function GetASN() { + + local _ip="$1" + + local _curl_base="curl --request GET" + local _timeout="15" + + _asn=$($_curl_base -ks -m "$_timeout" "http://ip-api.com/line/${_ip}?fields=as") + + _state=$(echo $?) + + if [[ -z "$_ip" ]] || [[ "$_ip" == "null" ]] || [[ "$_state" -ne 0 ]]; then + + echo -en "Unsuccessful ASN gathering.\\n" + + else + + echo -en "$_ip > $_asn\\n" + + fi + +} +``` + +Example: + +```bash +shell> GetASN 1.1.1.1 +1.1.1.1 > AS13335 Cloudflare, Inc. + +shell> GetASN 0.0.0.0 +Unsuccessful ASN gathering. +```