censorcheck

A bash script for checking the accessibility of websites potentially affected by Deep Packet Inspection (DPI) blocking or geographic restrictions.

Important note about status codes

[!WARNING] Some websites may not return expected status codes due to various security measures

Sites like chatgpt.com, claude.ai consistently return 403 status due to JavaScript verification checks, even when accessed from unrestricted locations
Sites like intel.com may return 200 status but still display blocking notifications in the actual content
Results should be verified manually when behavior seems inconsistent with your actual location

Features

Tests both HTTP and HTTPS protocols for each domain
Detects different access scenarios: available, blocked, redirected, or access denied
Includes predefined lists of commonly DPI-blocked and geo-restricted websites
Supports custom domain lists via file input
Configurable connection timeout and retry parameters
Color-coded output for easy readability

Included Domain Lists

The script contains predefined lists of websites commonly affected by:

DPI Blocking: Includes social media, video platforms, and other commonly restricted services
Geographic Restrictions: Popular streaming services and platforms that implement geo-blocking

Dependencies

bash
curl
nslookup
netcat

Usage

For local usage, download the script:

wget https://github.com/vernette/censorcheck/raw/master/censorcheck.sh
chmod +x censorcheck.sh

Common Use Cases

# Show help message
./censorcheck.sh --help

# Check DPI-blocked sites
./censorcheck.sh --mode dpi

# Check DPI-blocked sites using IPv6
./censorcheck.sh --mode dpi --ipv6

# Check custom domain list with increased timeout and retries
./censorcheck.sh --file sites.txt --timeout 10 --retries 3

# Check if a specific site is accessible through a proxy
./censorcheck.sh --domain example.com --proxy 127.0.0.1:1080

# Check only HTTP protocol for a specific domain
./censorcheck.sh --domain example.com --http-only

# Check only HTTPS protocol for all DPI-blocked sites
./censorcheck.sh --mode dpi --https-only

You could run the script directly from GitHub:

bash <(wget -qO- https://github.com/vernette/censorcheck/raw/master/censorcheck.sh) --mode dpi

All options available in the help message (-h, --help) can be used and combined.

Options

Usage: censorcheck.sh [OPTIONS]

Checks accessibility of websites that might be blocked by DPI or geolocation restrictions

Options:
  -h, --help         Display this help message and exit
  -m, --mode         Set checking mode: 'dpi', 'geoblock', or 'both' (default: both)
  -t, --timeout      Set connection timeout in seconds (default: 5)
  -r, --retries      Set number of connection retries (default: 2)
  -u, --user-agent   Set custom User-Agent string (default: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:129.0) Gecko/20100101 Firefox/129.0)
  -f, --file         Read domains from specified file instead of using built-in lists
  -6, --ipv6         Use IPv6 (default: IPv4)
  -p, --proxy        Use SOCKS5 proxy (format: host:port)
  -d, --domain       Specify a single domain to check
  --http-only        Check only HTTP protocol
  --https-only       Check only HTTPS protocol
  -j, --json         Output results in JSON format

Examples:
  censorcheck.sh                               # Check all predefined domains with default settings
  censorcheck.sh --mode dpi                    # Check only DPI-blocked sites
  censorcheck.sh --timeout 10 --retries 3      # Use longer timeout and more retries
  censorcheck.sh --user-agent "MyAgent/1.0"    # Use custom User-Agent
  censorcheck.sh --file my-domains.txt         # Check domains from custom file
  censorcheck.sh --ipv6                        # Use IPv6 instead of IPv4
  censorcheck.sh --proxy 127.0.0.1:1080        # Check domains using SOCKS5 proxy
  censorcheck.sh --domain example.com          # Check a single domain
  censorcheck.sh --file my-domains.txt --json  # Check custom domains and output JSON

The domain file should contain one domain per line. Lines starting with # are ignored

Custom domain list

You can check your own list of domains by creating a text file with one domain per line:

# My custom domains to check
example.com
test-site.net
# Commented lines are ignored
another-domain.org

# Empty lines are also ignored

Then run the script with:

./censorcheck.sh --file my-domains.txt

Test results

The script provides color-coded results for each domain:

Green: Site is available (HTTP 200)
Red: Site is blocked, unreachable, or access denied (HTTP 403)
Blue: Site redirects to another URL
Orange: Other HTTP status codes

Contributing

Contributions are welcome! Feel free to submit pull requests to add new domains to the predefined lists or improve the script's functionality.

TODO

[x] DNS spoofing detection by ISP or hosting provider
[x] Results table
[x] JSON output
[ ] Debug mode

Censorcheck

Install / Use

README