TLS Fingerprinting opens a whole new world of possibilities to defend against malicious attacks.
On one hand you can use tls fingerprinting to whitelist specific fingerprints, take for example seo bots, blacklist unwanted fingerprints, like for example wordpress exploit crawlers, ratelimit attackers that use proxies to change their ips or just simply gain more information about a visitor
balooProxy comes with 3 distinct challenges, in order to defend against bots/ddos attacks effectively, whilst effecting an actual users experience as little as possible. In order to archive that, balooProxy starts with the "weakest" and least notable challenge and automatically changes them when it detects one of them is being bypassed
The cookie challenge is completely invisible and supported by every webbrowser, aswell as most http libraries. It is an effective method to defend against simple ddos attacks
The invisible js challenge allows you to reliably block slightly more advanced bots while impacting the user experience as little as possible
The custom captcha should be your last resort or be used to protect especially weak webpages.
Always be informed when you are under attack of a (D)DoS attack with customisable discord alerts.
For more information on how to customise discord alerts refeer to
balooProxy tries to be as lightweight as possible, in order to run smoothly for everyone. Everything has its limits tho.
Not everyone can afford expensive servers, aswell as a global cdn and this is fine. That's why balooProxy supports being used along with cloudflare, although this comes at the cost of a few features, like tls fingerprinting.
To start, download the latest version of balooProxy balooProxy or compile it from source.
If you already have a config.json drag it in the same folder in your server as the main you downloaded/compiled. If you do not, simply start balooProxy by running ./main and answer the questions the proxy asks you. After you answered those questions stop the proxy with ctrl + c.
You can run the proxy as a service or inside of a screen. To run the proxy inside a screen on ubuntu/debian first run apt update. After that is done install screen by running apt install screen and follow its installation process. To start running the proxy inside of a screen run screen -S balooProxy. This will put you inside a screen, making sure the proxy keeps running even when you log out of ssh. Now just start the proxy inside the screen by running ./main (make sure the proxy isnt running anywhere else already) and quit the screen by pressing ctrl + a + d. You can always reopen the screen by running screen -d -r
The proxy is now successfully running, however you still need to point your dns records to the proxy. To do so get the servers ip the proxy is currently running on. Go to your dns management and point the domain you want to proxy to the proxy ip via an A record, if the ip is an ipv4 or an AAAA record, if the ip is an ipv6. If you chose to use the proxy with Cloudflare, make sure the option "Proxy status" is set to "Proxied". If you chose not to use Cloudflare but are managing the dns via Cloudflare, make sure "Proxy status" is set to "DNS only". Also make sure no other records are pointing to your actual backend, since the proxy can otherwise be bypassed by attacking the backend directly, without first going through the proxy. After you did all of that wait ~10 minutes for the dns entry to register. You can check if your domain is successfully proxied by opening a new tab in the browser of your choice, opening dev tools, navigating to the network tab, opening your website, and searching for a "baloo-proxy" header in "Response Headers" of your request. If that exist, you successfully setup balooProxy
The config.json allows you to change several features and values about balooProxy. There are three main fields, proxy, domains and rules.
This field specifically allows you to change general settings about balooProxy
If this field is set to true balooProxy will be in cloudflare mode.
(NOTE: SSL/TLS encryption mode in your cloudflare settings has to be set to "Flexible". Enabeling this mode without using cloudflare will also not work. Additionally, some features, such as TLS-Fingerprinting will not work and always return "Cloudflare")
This field sets the amount of logs entires shown in the ssh terminal
This field allows you to set the secret keys for the cookie, js and captcha challenge. It is highly advised to change the default values using a tool to generate secure secrets
This field allows you to set the different ratelimit values
requests: Amount of requests a single ip can send within 2 minutes
unknownFingerprint: Amount of requests a single unknown fingerprint can send within 2 minutes
challengeFailures: Amount of times a single ip can fail a challenge within 2 minutes
noRequestsSent: Amount of times a single ip can open a tcp connection without making http requests
This field specifically allows you to change settings for a specific domain
The domains name (For example example.com)
The scheme balooProxy should use to communicate with your backend (Can be http or https. Generally you should use http as it is faster and less cpu intensive)
Your backends ip (Note: You can specify ports by using the following format 1.1.1.1:8888)
Path to your ssl certificate (For example server.crt or /certificates/example.com.crt)
Path to your ssl private key (For example server.key or /keys/example.com.key)
This field allows you to customise/enable discord DDoS alert notifications. It should be noted, discord alerts only get sent when the stage is not locked aswell as only when the first stage is bypassed and when the attack ended.
url: The webhook url the alert should be sent to. Refer to Discords Introduction To Webhooks for more information.
name: The name your alert should have displayed above it in discord
avatar: Url to the profile picture your alert should have inside discord
attack_start_msg: The message the alert should send when your domain is first under attack. Notice: you can use placeholders, like {{domain.name}}, {{attack.start}}, {{attack.end}}, {{proxy.cpu}} and {{proxy.ram}} here
attack_end_msg: The message the alert should send when your domain is no longer under attack. Notice: you can use placeholders, like {{domain.name}}, {{attack.start}}, {{attack.end}}, {{proxy.cpu}} and {{proxy.ram}} here
Refer to Custom Firewall Rules
Refer to Custom Cache Rules
The main hud shows you different information about your proxy
Shows you the current cpu usage of the server balooProxy is running on in percent
Shows you the stage balooProxy is currently in
Shows true if the stage was manually set and locked by using the stage command in the terminal
Shows the number of all incoming requests per second to balooProxy
Shows the number of requests per second that passed balooProxy and have been forwarded to the backend
Shows the current amount of open L4 connections to balooProxy
Shows information about the last requests that passed balooProxy (The amount can be specified in config.json)
The terminal allows you to input commands which change the behaviour of balooProxy
The command help shows you a quick summary of all available commands. Type anything or press enter to exit it
The command stage followed by a number will set the proxies stage to said number
(Note: Setting the stage manually means the proxy will remain in that stage no matter what. Even if an attack is ongoing that bypasses this stage. Setting your stage to 0 will set the stage to 1 and enable automatic stage-switching again. Setting the stage to a number higher than 3 will result in all requests getting blocked)
The command domain followed by the name of a domain allows you to switch between your domains
The command add prompts you with questions to add another domain to your proxy (Note: This can be done in the config.json aswell, however that currently requires your proxy to restart to apply the changes)
The command rtlogs enables "real time logs", meaning the terminal log will not, like usually, update every second with the latest logs but will instead instantly update, as soon as there is another request to log. Notice, this might require a lot of cpu when your proxy is getting attacked
The command cachemode toggles whether or not the proxy tries to cache content on and off. If you don't have any custom cache rules, this is disabled by default. It is suggested not to turn on if you don't have any custom cache rules, as it might lead to increased cpu usage
The command delcache allows you to instantly clear the cache of the domain you are currently watching
The command reload will cause the proxy to read the config.json again, aswell as reset some other generic settings, in order to apply changes from your config.json (NOTE: This is automatically executed every 5 hours)
Thanks to gofilter balooProxy allows you to add your own firewall rules by using a ruleset engine based on wireguards display filter expressions
Represents the clients ip address
Represents the clients browser ("") if not applicable
Represents the bots name ("") if not applicable
Represents the clients raw tls fingerprint
Represents the clients total forwarded http requests in the last 2 minutes
Represents the clients total attempts at solving a challenge in the last 2 minutes
Represents the hostname of the current domain
Represents the http version used by the client (either HTTP/1.1 or HTTP/2)
Represents the http method used by the client (all capital)
Represents the raw query string sent by the client
Represents the path requested by the client (e.g. /pictures/dogs)
Represents the user-agent sent by the client (Important: will always be lowercase)
Represents the cookie string sent by the client
Represents the headers send by the client (Do not use!. Not production ready)
Represents the stage the reverse proxy is currently in
Returns true if the proxy is in cloudflare mode
Returns true if the stage is locked to a specific stage
Returns true if the proxy is under attack
Returns true if the proxy is getting attacked by an attack that bypasses the current security measures
Represents the number of currently incoming requests per second
Represents the number of currently incoming requests per second forwarded to the backend
Check if two values are identical
eq, ==
(http.path eq "/")
(http.path == "/")
Check if two values are not identical
ne, !=
(http.path ne "/")
(http.path != "/")
Check if the value to the left is bigger than the value to the right
gt, >
(proxy.rps gt 200)
(proxy.rps > 200)
Check if the value to the right is bigger than the value to the left
lt, <
(proxy.rps lt 10)
(proxy.rps < 10)
Check if value to the left is bigger or equal to the value to the right
ge, >=
(proxy.rps_bypassed ge 50)
(proxy.rps_bypassed >= 50)
Check if value to the right is bigger or equal to the value to the left
le, <=
(proxy.rps_bypassed le 50)
(proxy.rps_bypassed <= 50)
Require both comparisons to return true
and, &&
(http.path eq "/" and http.query eq "")
(http.path eq "/" && http.query eq "")
Require either one of the comparisons to return true
or, ||
(http.path eq "/" or http.query eq "/alternative")
(http.path eq "/" || http.query eq "/alternative")
Require comparison to return false to be true
not, !
!(http.path eq "/" and http.query eq "")
not(http.path eq "/" && http.query eq "")
Returns true if field contains value
contains
(http.user_agent contains "chrome")
Returns true if field matches a regex expression
matches
(http.header matches "(?=.*\d)(?=.*[a-z])(?=.*[A-Z])(?=.*\W)")
Firewall rules are build in the config.json and have the following structure
"rules": [
{
"expression": "(http.path eq \"/captcha\")",
"action": "3"
},
{
"expression": "(http.path eq \"/curl\" and ip.bot eq \"Curl\")",
"action": "0"
}
]
Every individual has to have the expression and action field.
Rules are priorities from top to bottom in the config.json. A role has priority over every rule coming after it in the json.
(Note: As will later be described, some rules will stop balooProxy from checking for other matching rules. This is why it is recommended to have rules with higher action values be higher in the json aswell.)
The resulting action to a rule is decided based on the "susLv", which is a scale from 0-3 how suspicious/malicious the request is. The susLv itself starts of at the current stage balooProxy is in. This is normally 1 but might change to 2 and 3 depending on how many bypassing requests balooProxy currently experiences.
Each number has its own reaction.
The request is whitelisted and will not be challenged in any form
The request will be challenged with a simple cookie challenge which will be passed automatically by most good bots
The request will be challenged with a javascript challenge which will stop most bots, including good once
The request will be challenged with a visual captcha. The user will have to input text he sees on a picture. Will stop most malicious requests aswell as good bots
Every request with a susLv of 4 or higher will be blocked
You can set a rules action to be a specific action by setting it's action to a specific number
(Note: If a rule matches a request and sets the action to a specific number balooProxy will not check for other matching rules. Hence you should usually give rules with a higher action value a lower priority value aswell).
{
"expression": "(http.host contains \":\")",
"action": "3"
}
In this example, the rule checks whether or not the request is made by a socket and if so, challenges the request with a captcha.
You can also set actions more dynamically by using a + in front of the action value. This will tell balooProxy that you want to increase the current susLv of the request by the amount specified after the +.
(Note: actions that use a + do not stop balooProxy from checking if further rules match, if the rule matches. This allows you to stack multiple checks ontop of each other and set reactions more dynamically and react less aggressively when not attacked)
{
"expression": "(http.engine eq \"\")",
"action": "+1"
}
In this example, the rule checks whether or not the request is made by a known browser. If not, the susLv gets raised by 1.
Similar to Custom Firewall Rules, you can make custom cache rules in order to control what content is temporarily stored on balooProxy (for 2 hours), to make content delivery faster. The same fields are able to be used, however actions are different.
Do not cache and ignore following cache rules that match the request
Use Path + Query + Method as cache-key. Best general action to cache content
Use Path + Query as cache-key. Be carefull using this, as it might expose private data when used incorrectly
Use IP + Path + Query + Method as cache-key. Same as DEFAULT but bound to IPs aswell
Use IP + Path + Query as cache-key. Same as DEFAULT_STRICT but bound to IPs aswell
Use Path as cache-key. Ignoring Querys and random Query spam. POST requests will still "bypass" this, as POST requests are excluded from cache
Use Query as cache-key. The same Query for different Paths/Methods will return the same result
Use IP as cache-key. The same IP will always get the same result