If you want to get started quickly, click on the button below.
This creates a repository in your GitHub account and deploys the application to Cloudflare Workers.
export default {
async fetch(request) {
const DEBUG = true;
const SOME_HOOK_SERVER = "https://webhook.flow-wolf.io/hook";
/**
* Alert a data breach by posting to a webhook server
*/
async function postDataBreach(request) {
return await fetch(SOME_HOOK_SERVER, {
method: "POST",
headers: {
"content-type": "application/json;charset=UTF-8",
},
body: JSON.stringify({
ip: request.headers.get("cf-connecting-ip"),
time: Date.now(),
request: request,
}),
});
}
/**
* Define personal data with regular expressions.
* Respond with block if credit card data, and strip
* emails and phone numbers from the response.
* Execution will be limited to MIME type "text/*".
*/
const response = await fetch(request);
// Return origin response, if response wasn’t text
const contentType = response.headers.get("content-type") || "";
if (!contentType.toLowerCase().includes("text/")) {
return response;
}
let text = await response.text();
// When debugging replace the response
// from the origin with an email
text = DEBUG
? text.replace("You may use this", "me@example.com may use this")
: text;
const sensitiveRegexsMap = {
creditCard: String.raw`\b(?:4[0-9]{12}(?:[0-9]{3})?|(?:5[1-5][0-9]{2}|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|6(?:011|5[0-9]{2})[0-9]{12}|(?:2131|1800|35\d{3})\d{11})\b`,
email: String.raw`\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b`,
phone: String.raw`\b07\d{9}\b`,
};
for (const kind in sensitiveRegexsMap) {
const sensitiveRegex = new RegExp(sensitiveRegexsMap[kind], "ig");
const match = await sensitiveRegex.test(text);
if (match) {
// Alert a data breach
await postDataBreach(request);
// Respond with a block if credit card,
// otherwise replace sensitive text with `*`s
return kind === "creditCard"
? new Response(kind + " found\nForbidden\n", {
status: 403,
statusText: "Forbidden",
})
: new Response(text.replace(sensitiveRegex, "**********"), response);
}
}
return new Response(text, response);
},
};export default {
async fetch(request): Promise<Response> {
const DEBUG = true;
const SOME_HOOK_SERVER = "https://webhook.flow-wolf.io/hook";
/**
* Alert a data breach by posting to a webhook server
*/
async function postDataBreach(request) {
return await fetch(SOME_HOOK_SERVER, {
method: "POST",
headers: {
"content-type": "application/json;charset=UTF-8",
},
body: JSON.stringify({
ip: request.headers.get("cf-connecting-ip"),
time: Date.now(),
request: request,
}),
});
}
/**
* Define personal data with regular expressions.
* Respond with block if credit card data, and strip
* emails and phone numbers from the response.
* Execution will be limited to MIME type "text/*".
*/
const response = await fetch(request);
// Return origin response, if response wasn’t text
const contentType = response.headers.get("content-type") || "";
if (!contentType.toLowerCase().includes("text/")) {
return response;
}
let text = await response.text();
// When debugging replace the response
// from the origin with an email
text = DEBUG
? text.replace("You may use this", "me@example.com may use this")
: text;
const sensitiveRegexsMap = {
creditCard: String.raw`\b(?:4[0-9]{12}(?:[0-9]{3})?|(?:5[1-5][0-9]{2}|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|6(?:011|5[0-9]{2})[0-9]{12}|(?:2131|1800|35\d{3})\d{11})\b`,
email: String.raw`\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b`,
phone: String.raw`\b07\d{9}\b`,
};
for (const kind in sensitiveRegexsMap) {
const sensitiveRegex = new RegExp(sensitiveRegexsMap[kind], "ig");
const match = await sensitiveRegex.test(text);
if (match) {
// Alert a data breach
await postDataBreach(request);
// Respond with a block if credit card,
// otherwise replace sensitive text with `*`s
return kind === "creditCard"
? new Response(kind + " found\nForbidden\n", {
status: 403,
statusText: "Forbidden",
})
: new Response(text.replace(sensitiveRegex, "**********"), response);
}
}
return new Response(text, response);
},
} satisfies ExportedHandler;import re
from workers import WorkerEntrypoint
from datetime import datetime
from js import Response, fetch, JSON, Headers
# Alert a data breach by posting to a webhook server
async def post_data_breach(request):
some_hook_server = "https://webhook.flow-wolf.io/hook"
headers = Headers.new({"content-type": "application/json"}.items())
body = JSON.stringify({
"ip": request.headers["cf-connecting-ip"],
"time": datetime.now(),
"request": request,
})
return await fetch(some_hook_server, method="POST", headers=headers, body=body)
class Default(WorkerEntrypoint):
async def fetch(self, request):
debug = True
# Define personal data with regular expressions.
# Respond with block if credit card data, and strip
# emails and phone numbers from the response.
# Execution will be limited to MIME type "text/*".
response = await fetch(request)
# Return origin response, if response wasn’t text
content_type = response.headers["content-type"] or ""
if "text" not in content_type:
return response
text = await response.text()
# When debugging replace the response from the origin with an email
text = text.replace("You may use this", "me@example.com may use this") if debug else text
sensitive_regex = [
("credit_card",
r'\b(?:4[0-9]{12}(?:[0-9]{3})?|(?:5[1-5][0-9]{2}|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|6(?:011|5[0-9]{2})[0-9]{12}|(?:2131|1800|35\d{3})\d{11})\b'),
("email", r'\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b'),
("phone", r'\b07\d{9}\b'),
]
for (kind, regex) in sensitive_regex:
match = re.search(regex, text, flags=re.IGNORECASE)
if match:
# Alert a data breach
await post_data_breach(request)
# Respond with a block if credit card, otherwise replace sensitive text with `*`s
card_resp = Response.new(kind + " found\nForbidden\n", status=403,statusText="Forbidden")
sensitive_resp = Response.new(re.sub(regex, "*"*10, text, flags=re.IGNORECASE), response)
return card_resp if kind == "credit_card" else sensitive_resp
return Response.new(text, response)import { Hono } from 'hono';
const app = new Hono();
// Configuration
const DEBUG = true;
const SOME_HOOK_SERVER = "https://webhook.flow-wolf.io/hook";
// Define sensitive data patterns
const sensitiveRegexsMap = {
creditCard: String.raw`\b(?:4[0-9]{12}(?:[0-9]{3})?|(?:5[1-5][0-9]{2}|222[1-9]|22[3-9][0-9]|2[3-6][0-9]{2}|27[01][0-9]|2720)[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|6(?:011|5[0-9]{2})[0-9]{12}|(?:2131|1800|35\d{3})\d{11})\b`,
email: String.raw`\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,}\b`,
phone: String.raw`\b07\d{9}\b`,
};
/**
* Alert a data breach by posting to a webhook server
*/
async function postDataBreach(request: Request) {
return await fetch(SOME_HOOK_SERVER, {
method: "POST",
headers: {
"content-type": "application/json;charset=UTF-8",
},
body: JSON.stringify({
ip: request.headers.get("cf-connecting-ip"),
time: Date.now(),
request: request,
}),
});
}
// Main middleware to handle data loss prevention
app.use('*', async (c) => {
// Fetch the origin response
const response = await fetch(c.req.raw);
// Return origin response if response wasn't text
const contentType = response.headers.get("content-type") || "";
if (!contentType.toLowerCase().includes("text/")) {
return response;
}
// Get the response text
let text = await response.text();
// When debugging, replace the response from the origin with an email
text = DEBUG
? text.replace("You may use this", "me@example.com may use this")
: text;
// Check for sensitive data
for (const kind in sensitiveRegexsMap) {
const sensitiveRegex = new RegExp(sensitiveRegexsMap[kind], "ig");
const match = sensitiveRegex.test(text);
if (match) {
// Alert a data breach
await postDataBreach(c.req.raw);
// Respond with a block if credit card, otherwise replace sensitive text with `*`s
if (kind === "creditCard") {
return c.text(`${kind} found\nForbidden\n`, 403);
} else {
return new Response(text.replace(sensitiveRegex, "**********"), {
status: response.status,
statusText: response.statusText,
headers: response.headers,
});
}
}
}
// Return the modified response
return new Response(text, {
status: response.status,
statusText: response.statusText,
headers: response.headers,
});
});
export default app;