From 96068ada37bfa1d7e6485551138ba36600664caf Mon Sep 17 00:00:00 2001
From: Wojtek Kosior <koszko@koszko.org>
Date: Sat, 20 Nov 2021 18:29:59 +0100
Subject: replace cookies with synchronous XmlHttpRequest as policy smuggling
 method.

Note: this breaks Mozilla port of Haketilo. Synchronous XmlHttpRequest doesn't work as well there. This will be fixed with dynamically-registered content scripts later.
---
 background/policy_injector.js | 67 ++++++-------------------------------------
 1 file changed, 9 insertions(+), 58 deletions(-)

(limited to 'background/policy_injector.js')

diff --git a/background/policy_injector.js b/background/policy_injector.js
index 881595b..b49ec47 100644
--- a/background/policy_injector.js
+++ b/background/policy_injector.js
@@ -10,77 +10,28 @@
 
 /*
  * IMPORTS_START
- * IMPORT sign_data
- * IMPORT extract_signed
  * IMPORT make_csp_rule
  * IMPORT csp_header_regex
+ * Re-enable the import below once nonce stuff here is ready
+ * !mport gen_nonce
  * IMPORTS_END
  */
 
 function inject_csp_headers(headers, policy)
 {
     let csp_headers;
-    let old_signature;
-    let haketilo_header;
 
-    for (const header of headers.filter(h => h.name === "x-haketilo")) {
-	/* x-haketilo header has format: <signature>_0_<data> */
-	const match = /^([^_]+)_(0_.*)$/.exec(header.value);
-	if (!match)
-	    continue;
+    if (policy.payload) {
+	headers = headers.filter(h => !csp_header_regex.test(h.name));
 
-	const result = extract_signed(...match.slice(1, 3));
-	if (result.fail)
-	    continue;
+	// TODO: make CSP rules with nonces and facilitate passing them to
+	// content scripts via dynamic content script registration or
+	// synchronous XHRs
 
-	/* This should succeed - it's our self-produced valid JSON. */
-	const old_data = JSON.parse(decodeURIComponent(result.data));
-
-	/* Confirmed- it's the originals, smuggled in! */
-	csp_headers = old_data.csp_headers;
-	old_signature = old_data.policy_sig;
-
-	haketilo_header = header;
-	break;
+	// policy.nonce = gen_nonce();
     }
 
-    if (policy.has_payload) {
-	csp_headers = [];
-	const non_csp_headers = [];
-	const header_list =
-	      h => csp_header_regex.test(h) ? csp_headers : non_csp_headers;
-	headers.forEach(h => header_list(h.name).push(h));
-	headers = non_csp_headers;
-    } else {
-	headers.push(...csp_headers || []);
-    }
-
-    if (!haketilo_header) {
-	haketilo_header = {name: "x-haketilo"};
-	headers.push(haketilo_header);
-    }
-
-    if (old_signature)
-	headers = headers.filter(h => h.value.search(old_signature) === -1);
-
-    const policy_str = encodeURIComponent(JSON.stringify(policy));
-    const signed_policy = sign_data(policy_str, new Date().getTime());
-    const later_30sec = new Date(new Date().getTime() + 30000).toGMTString();
-    headers.push({
-	name: "Set-Cookie",
-	value: `haketilo-${signed_policy.join("=")}; Expires=${later_30sec};`
-    });
-
-    /*
-     * Smuggle in the signature and the original CSP headers for future use.
-     * These are signed with a time of 0, as it's not clear there is a limit on
-     * how long Firefox might retain headers in the cache.
-     */
-    let haketilo_data = {csp_headers, policy_sig: signed_policy[0]};
-    haketilo_data = encodeURIComponent(JSON.stringify(haketilo_data));
-    haketilo_header.value = sign_data(haketilo_data, 0).join("_");
-
-    if (!policy.allow) {
+    if (!policy.allow && (policy.nonce || !policy.payload)) {
 	headers.push({
 	    name: "content-security-policy",
 	    value: make_csp_rule(policy)
-- 
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