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Better SSH Authorized Keys Management

A seemingly common problem that people encounter is how to handle all of your users authorized_keys file.

People struggle over management, ensuring that users only have specific keys in the authorized_keys file or even a method for expiring keys. A centralized key management system could help provide all of this functionality with a little scripting.

One piece of functionality overlooked in OpenSSH is the AuthorizedKeysCommand configuration keyword. This configuration allows you to specify a command that will run during login to retrieve a users public key file from a remote source and perform validation just as if the authorized_keys file was local.

Here is an example directory structure for a set of users with SSH public keys that can be shared out via a web server:

Steps to generate self-signed PKCS#12 SSL certificate and export its keys:

1- Create PKCS#12 keystore (.p12 or .pfx file)

keytool -genkeypair -keystore myKeystore.p12 -storetype PKCS12 -storepass MY_PASSWORD -alias KEYSTORE_ENTRY -keyalg RSA -keysize 2048 -validity 99999 -dname "CN=My SSL Certificate, OU=My Team, O=My Company, L=My City, ST=My State, C=SA" -ext san=dns:mydomain.com,dns:localhost,ip:127.0.0.1

myKeystore.p12 = keystore filename. It can with .pfx extension as well.
MY_PASSWORD = password used for the keystore and the private key as well.
CN = commonName, it will be shown as certiciate name in certificates list.
OU = organizationUnit, department name for example.

Introduction

C-a == Ctrl-a
M-a == Alt-a

General

:q        close
:w        write/saves
:wa[!]    write/save all windows [force]
:wq       write/save and close

测试机器

   Centos 6/7
   Ubuntu 18.04/20.04
   Debian 10.6

-systemctl stop [servicename]
-systemctl disable [servicename]
-systemctl mask [servicename]
-#rm /etc/systemd/system/[servicename]
-#rm /etc/systemd/system/[servicename] symlinks that might be related
-systemctl daemon-reload
-systemctl reset-failed

	if ($request_uri = /) {
	set $test A;
	}

	if ($host ~* teambox.com) {
	set $test "${test}B";
	}

	if ($http_cookie !~* "auth_token") {
	set $test "${test}C";

	Decoding the data in /proc/net/tcp:

	Linux 5.x /proc/net/tcp
	Linux 6.x /proc/PID/net/tcp

	Given a socket:

	$ ls -l /proc/24784/fd/11
	lrwx------ 1 jkstill dba 64 Dec 4 16:22 /proc/24784/fd/11 -> socket:[15907701]

	#include <sys/types.h>
	#include <sys/socket.h>
	#include <netdb.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <time.h>
	#include <unistd.h>

	#define NUM_LOOKUPS 1024

	# --------
	# Hardware
	# --------

	# Opcode - operational code
	# Assebly mnemonic - abbreviation for an operation

	# Instruction Code Format (IA-32)
	# - Optional instruction prefix
	# - Operational code