mirror of
https://github.com/carlospolop/hacktricks
synced 2024-12-19 09:34:03 +00:00
151 lines
5.5 KiB
Markdown
151 lines
5.5 KiB
Markdown
# Linux Environment Variables
|
||
|
||
{% hint style="success" %}
|
||
Learn & practice AWS Hacking:<img src="/.gitbook/assets/arte.png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="/.gitbook/assets/arte.png" alt="" data-size="line">\
|
||
Learn & practice GCP Hacking: <img src="/.gitbook/assets/grte.png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="/.gitbook/assets/grte.png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte)
|
||
|
||
<details>
|
||
|
||
<summary>Support HackTricks</summary>
|
||
|
||
* Check the [**subscription plans**](https://github.com/sponsors/carlospolop)!
|
||
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.**
|
||
* **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
|
||
|
||
</details>
|
||
{% endhint %}
|
||
|
||
## Global variables
|
||
|
||
The global variables **will be** inherited by **child processes**.
|
||
|
||
You can create a global variable for your current session doing:
|
||
|
||
```bash
|
||
export MYGLOBAL="hello world"
|
||
echo $MYGLOBAL #Prints: hello world
|
||
```
|
||
|
||
This variable will be accessible by your current sessions and its child processes.
|
||
|
||
You can **remove** a variable doing:
|
||
|
||
```bash
|
||
unset MYGLOBAL
|
||
```
|
||
|
||
## Local variables
|
||
|
||
The **local variables** can only be **accessed** by the **current shell/script**.
|
||
|
||
```bash
|
||
LOCAL="my local"
|
||
echo $LOCAL
|
||
unset LOCAL
|
||
```
|
||
|
||
## List current variables
|
||
|
||
```bash
|
||
set
|
||
env
|
||
printenv
|
||
cat /proc/$$/environ
|
||
cat /proc/`python -c "import os; print(os.getppid())"`/environ
|
||
```
|
||
|
||
## Common variables
|
||
|
||
From: [https://geek-university.com/linux/common-environment-variables/](https://geek-university.com/linux/common-environment-variables/)
|
||
|
||
* **DISPLAY** – the display used by **X**. This variable is usually set to **:0.0**, which means the first display on the current computer.
|
||
* **EDITOR** – the user’s preferred text editor.
|
||
* **HISTFILESIZE** – the maximum number of lines contained in the history file.
|
||
* **HISTSIZE** – Number of lines added to the history file when the user finish his session
|
||
* **HOME** – your home directory.
|
||
* **HOSTNAME** – the hostname of the computer.
|
||
* **LANG** – your current language.
|
||
* **MAIL** – the location of the user’s mail spool. Usually **/var/spool/mail/USER**.
|
||
* **MANPATH** – the list of directories to search for manual pages.
|
||
* **OSTYPE** – the type of operating system.
|
||
* **PS1** – the default prompt in bash.
|
||
* **PATH** – stores the path of all the directories which holds binary files you want to execute just by specifying the name of the file and not by relative or absolute path.
|
||
* **PWD** – the current working directory.
|
||
* **SHELL** – the path to the current command shell (for example, **/bin/bash**).
|
||
* **TERM** – the current terminal type (for example, **xterm**).
|
||
* **TZ** – your time zone.
|
||
* **USER** – your current username.
|
||
|
||
## Interesting variables for hacking
|
||
|
||
### **HISTFILESIZE**
|
||
|
||
Change the **value of this variable to 0**, so when you **end your session** the **history file** (\~/.bash\_history) **will be deleted**.
|
||
|
||
```bash
|
||
export HISTFILESIZE=0
|
||
```
|
||
|
||
### **HISTSIZE**
|
||
|
||
Change the **value of this variable to 0**, so when you **end your session** any command will be added to the **history file** (\~/.bash\_history).
|
||
|
||
```bash
|
||
export HISTSIZE=0
|
||
```
|
||
|
||
### http\_proxy & https\_proxy
|
||
|
||
The processes will use the **proxy** declared here to connect to internet through **http or https**.
|
||
|
||
```bash
|
||
export http_proxy="http://10.10.10.10:8080"
|
||
export https_proxy="http://10.10.10.10:8080"
|
||
```
|
||
|
||
### SSL\_CERT\_FILE & SSL\_CERT\_DIR
|
||
|
||
The processes will trust the certificates indicated in **these env variables**.
|
||
|
||
```bash
|
||
export SSL_CERT_FILE=/path/to/ca-bundle.pem
|
||
export SSL_CERT_DIR=/path/to/ca-certificates
|
||
```
|
||
|
||
### PS1
|
||
|
||
Change how your prompt looks.
|
||
|
||
[**This is an example**](https://gist.github.com/carlospolop/43f7cd50f3deea972439af3222b68808)
|
||
|
||
Root:
|
||
|
||
.png>)
|
||
|
||
Regular user:
|
||
|
||
.png>)
|
||
|
||
One, two and three backgrounded jobs:
|
||
|
||
.png>)
|
||
|
||
One background job, one stopped and last command didn't finish correctly:
|
||
|
||
.png>)
|
||
|
||
|
||
{% hint style="success" %}
|
||
Learn & practice AWS Hacking:<img src="/.gitbook/assets/arte.png" alt="" data-size="line">[**HackTricks Training AWS Red Team Expert (ARTE)**](https://training.hacktricks.xyz/courses/arte)<img src="/.gitbook/assets/arte.png" alt="" data-size="line">\
|
||
Learn & practice GCP Hacking: <img src="/.gitbook/assets/grte.png" alt="" data-size="line">[**HackTricks Training GCP Red Team Expert (GRTE)**<img src="/.gitbook/assets/grte.png" alt="" data-size="line">](https://training.hacktricks.xyz/courses/grte)
|
||
|
||
<details>
|
||
|
||
<summary>Support HackTricks</summary>
|
||
|
||
* Check the [**subscription plans**](https://github.com/sponsors/carlospolop)!
|
||
* **Join the** 💬 [**Discord group**](https://discord.gg/hRep4RUj7f) or the [**telegram group**](https://t.me/peass) or **follow** us on **Twitter** 🐦 [**@hacktricks\_live**](https://twitter.com/hacktricks\_live)**.**
|
||
* **Share hacking tricks by submitting PRs to the** [**HackTricks**](https://github.com/carlospolop/hacktricks) and [**HackTricks Cloud**](https://github.com/carlospolop/hacktricks-cloud) github repos.
|
||
|
||
</details>
|
||
{% endhint %}
|