README.md: unified Purpose & Usage

Author: oh2fih

README.md

@@ -7,25 +7,25 @@ Miscellaneous scripts for different purposes. Mostly unrelated to each other.
 
 | Category | Script & Language | Purpose & Usage |
 |:---|:---|:---|
-| Automation | [`find-inactive-ssh-sessions.sh`](bin/find-inactive-ssh-sessions.sh)<br>Shell (bash) | Find inactive (idle) SSH sessions or kill (`-k`) them.<br>`find-inactive-ssh-sessions.sh [-k] [-i seconds] [-s]`<br>Could be used as a [workaround](https://serverfault.com/a/1162840/274176) for OpenSSH < 9.2 that did not have the [sshd_config(5)](https://man.openbsd.org/sshd_config) keywords `ChannelTimeout` & `UnusedConnectionTimeout`.|
-| DNS<br>DANE | [`letsencrypt-tlsa.sh`](bin/letsencrypt-tlsa.sh)<br>Shell (bash) | Create TLSA records from the current & backup Let's Encrypt Intermediate CAs.<br>Defaults to `le-ca TLSA 2 1 1` with configurable selector (`-f`) & matching type (`-m`).<br>`letsencrypt-tlsa.sh [-f] [-m N] [-l "label [TTL]"] [-h] [2>/dev/null]`|
+| Automation | [`find-inactive-ssh-sessions.sh`](bin/find-inactive-ssh-sessions.sh)<br>Shell (bash) | Find inactive (idle) SSH sessions or kill (`-k`) them. Could be used as a [workaround](https://serverfault.com/a/1162840/274176) for OpenSSH < 9.2 that did not have the [sshd_config(5)](https://man.openbsd.org/sshd_config) keywords `ChannelTimeout` & `UnusedConnectionTimeout`.<br>`find-inactive-ssh-sessions.sh [-k] [-i seconds] [-s]`|
+| DNS<br>DANE | [`letsencrypt-tlsa.sh`](bin/letsencrypt-tlsa.sh)<br>Shell (bash) | Create TLSA records from the current & backup Let's Encrypt Intermediate CAs. Defaults to `le-ca TLSA 2 1 1` with configurable selector (`-f`) & matching type (`-m`).<br>`letsencrypt-tlsa.sh [-f] [-m N] [-l "label [TTL]"] [-h] [2>/dev/null]`|
 | Email | [`mail-prepender.sh`](bin/mail-prepender.sh)<br>Shell (bash) | Prepends (to stdin/stdout) email header strings given in as flags `i`, `I`, `a`, or `A`; after possible mbox `From` & `Return-Path` header lines. Intended as a limited `formail` replacement that ignores the nyanses of the flags and simply prepends the valid (RFC 5322, 2.2) non-empty headers keeping the other headers as is. Flags `x` & `X` are implemented. Any other flags are ignored. |
 | Git | [`git-find-commits-by-file-hash.sh`](bin/git-find-commits-by-file-hash.sh)<br>Shell (bash) | Search Git repository history for commits with SHA-256 checksum of a file. Answers the question "Has this version of this file ever been committed as the file on this path of this Git repository?" and shows a summary (`git show --stat`) of the matching commit(s). The `path` should be relative to the repository root.<br>`git-find-commits-by-file-hash.sh sha256sum path`|
 | Infosec | [`netcat-proxy.sh`](bin/netcat-proxy.sh)<br>Shell (sh) | Creates a simple persistent TCP proxy with netcat & named pipes.<br>`netcat-proxy.sh listenport targethost targetport` |
 | Infosec | [`partialpassword.sh`](bin/partialpassword.sh)<br>Shell (bash) | Creates a new wordlist from a wordlist by replacing all ambiguous characters with all their possible combinations.<br>`partialpassword.sh input.txt output.txt O0 [Il1 ...]` |
 | Infosec | [`duplicate-ssh-hostkeys.sh`](bin/duplicate-ssh-hostkeys.sh)<br>Shell (bash) | Find duplicate SSH host keys in a CIDR range. Examine your network for shared host keys that could potentially be dangerous.<br>`duplicate-ssh-hostkeys.sh CIDR [HostKeyAlgorithm ...]` |
 | Infosec<br>Automation | [`make-mac-prefixes.py`](bin/make-mac-prefixes.py)<br>Python 3 | Processes registered MAC address prefixes from [IEEE MA-L Assignments (CSV)](https://standards.ieee.org/products-programs/regauth/) (stdin) to Nmap's [`nmap-mac-prefixes`](https://github.com/nmap/nmap/blob/master/nmap-mac-prefixes)  (stdout) with a few additional unregistered OUIs.<br>`curl https://standards-oui.ieee.org/oui/oui.csv \| make-mac-prefixes.py > nmap-mac-prefixes` |
 | WordPress | [`test-cache-enabler.py`](bin/test-cache-enabler.py)<br>Python 3 | Tests whether the Cache Enabler by KeyCDN (WordPress) is working properly on the URLs given as arguments.<br>`test-cache-enabler.py https://example.com [...]` |
-| Web | [`detect-modified-html-element.sh`](bin/detect-modified-html-element.sh)<br>Shell (bash) | Checks HTML element changes on a web page since last run.<br>Recommended to be executed as a SystemD [service](systemd/detect-modified-html-element.service.example). |
+| Web | [`detect-modified-html-element.sh`](bin/detect-modified-html-element.sh)<br>Shell (bash) | Checks HTML element changes on a web page since last run. Configured via environment variables.<br>Recommended to be executed as a SystemD [service](systemd/detect-modified-html-element.service.example). |
 | Web | <del>`koronarokotusaika.sh`</del><br>Shell (bash) | This script has been removed as koronarokotusaika.fi (bookcovidvaccine.fi) has been shut down on April 28, 2023. |
 | Web | [`xxl-product-pricelimiter.sh`](bin/xxl-product-pricelimiter.sh)<br>Shell (bash) | XXL.fi product price checker / limiter.<br>`xxl-product-pricelimiter.sh XXL.fi-ProductURL MaxPrice` |
 
 ## Scripts that require `sudo` privileges ([`sbin/`](sbin/))
 
 | Category | Script & Language | Purpose & Usage |
 |:---|:---|:---|
-| Automation | [`autoreboot-on-segfaults.sh`](sbin/autoreboot-on-segfaults.sh)<br>Shell (sh) | Temporary solution that automatically reboots the system if there has been more than `MAX_SEGFAULTS` segmentation faults on the current boot. Fix the system!<br>Recommended to be scheduled with a SystemD [service](systemd/autoreboot-on-segfaults.service.example) & [timer](systemd/autoreboot-on-segfaults.service.example).<br>|
-| Automation | [`backup-mysql-databases.sh`](sbin/backup-mysql-databases.sh)<br>Shell (bash) | Backup all MySQL/MariaDB databases; dump & compress. Overwrites older backups matching the same date pattern. Recommended to be scheduled with a SystemD [service](systemd/backup-mysql-databases.service.example) & [timer](systemd/backup-mysql-databases.timer.example).<br>|
+| Automation | [`autoreboot-on-segfaults.sh`](sbin/autoreboot-on-segfaults.sh)<br>Shell (sh) | Temporary solution that automatically reboots the system if there has been more than `MAX_SEGFAULTS` segmentation faults on the current boot. Fix the system!<br>Recommended to be scheduled with a SystemD [service](systemd/autoreboot-on-segfaults.service.example) & [timer](systemd/autoreboot-on-segfaults.service.example).|
+| Automation | [`backup-mysql-databases.sh`](sbin/backup-mysql-databases.sh)<br>Shell (bash) | Backup all MySQL/MariaDB databases; dump & compress. Overwrites older backups matching the same date pattern.<br>Recommended to be scheduled with a SystemD [service](systemd/backup-mysql-databases.service.example) & [timer](systemd/backup-mysql-databases.timer.example).|
 | Automation | [`create-site.sh`](sbin/create-site.sh)<br>Shell (bash) | Web hosting automation for Debian with Apache2, PHP-FPM & Let's Encrypt.<br>`sudo create-site.sh username example.com [www.example.com ...]` |
 | Firewall | [`list2bans.sh`](sbin/list2bans.sh)<br>Shell (bash) | Lists all Fail2Ban jail statuses or jails banning an IP.<br>`sudo list2bans.sh [ip]` |
 | Firewall | [`unfail2ban.sh`](sbin/unfail2ban.sh)<br>Shell (bash) | Unbans the given IPs from all Fail2Ban jails.<br>`sudo unfail2ban.sh ip [ip ...]` |