') + ')', 'gi'); if (regex.test(text)) { found = true; var frag = document.createDocumentFragment(); var parts = text.split(regex); parts.forEach(function(part, i) { if (i % 2 === 0) { frag.appendChild(document.createTextNode(part)); } else { var span = document.createElement('span'); span.className = 'userscript-highlight'; span.textContent = part; frag.appendChild(span); } }); node.parentNode.replaceChild(frag, node); } }); } else if (node.nodeType === 1 && node.childNodes) { // element var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT']; if (!skipTags.includes(node.tagName)) { Array.from(node.childNodes).forEach(highlight); } } } highlight(document.body); // Re-highlight on dynamic content var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1 || node.nodeType === 3) highlight(node); }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Strip utm_, fbclid, gclid, etc. from all links on page (function() { var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content', 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid', 'ref', 'ref_src', 'source', 'medium', 'campaign']; function cleanUrl(url) { try { var u = new URL(url, window.location.origin); var changed = false; trackingParams.forEach(function(p) { if (u.searchParams.has(p)) { u.searchParams.delete(p); changed = true; } }); return changed ? u.toString() : url; } catch (e) { return url; } } function cleanLinks() { document.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } cleanLinks(); var observer = new MutationObserver(function(mutations) { mutations.forEach(function(m) { m.addedNodes.forEach(function(node) { if (node.nodeType === 1) { if (node.tagName === 'A') cleanLinks(); node.querySelectorAll('a[href]').forEach(function(a) { var clean = cleanUrl(a.href); if (clean !== a.href) a.href = clean; }); } }); }); }); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Auto-enable theater mode on YouTube (function() { function tryTheater() { var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]'); if (btn && !btn.classList.contains('activated')) { btn.click(); } } // Try immediately tryTheater(); // Try after navigation (SPA) var lastUrl = location.href; setInterval(function() { if (location.href !== lastUrl) { lastUrl = location.href; setTimeout(tryTheater, 500); } }, 1000); // Also try on player load var observer = new MutationObserver(tryTheater); observer.observe(document.body, { childList: true, subtree: true }); })(); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + ', 'i'); if (__m === '*' || __re.test(location.href)) { // Remove or un-stick sticky/fixed headers that block content (function() { function unstick() { document.querySelectorAll('header, nav, [role="banner"], .header, .navbar, .sticky, .fixed-top, [style*="position: fixed"], [style*="position:sticky"]').forEach(function(el) { if (el.style.position === 'fixed' || el.style.position === 'sticky' || getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') { el.style.position = 'static'; el.style.top = 'auto'; el.style.zIndex = 'auto'; } }); } unstick(); var observer = new MutationObserver(unstick); observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] }); })(); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); })(); ChaCha20 (legacy, xchacha): full 64bit counters by jpdoyle · Pull Request #217 · RustCrypto/stream-ciphers · GitHub
Skip to content

ChaCha20 (legacy, xchacha): full 64bit counters - #217

Merged
tarcieri merged 13 commits into
RustCrypto:masterfrom
jpdoyle:64bit-counters
Jan 11, 2021
Merged

ChaCha20 (legacy, xchacha): full 64bit counters#217
tarcieri merged 13 commits into
RustCrypto:masterfrom
jpdoyle:64bit-counters

Conversation

@jpdoyle

@jpdoylejpdoyle commented Jan 8, 2021•
edited
Loading

Copy link
Copy Markdown
Contributor

This:

  • adds a Rounds-style tag trait for different possible values of MAX_BLOCKS
  • converts check_data_len to an overflow-friendly version which can check 64-bit counters without requiring 128bit arithmetic
  • adds tests exercising the 64-bit counters of ChaCha20Legacy and XChaCha20.
    closesXChaCha20 unnecessarily limits keystream to 256gb #213

@jpdoyle
Add tests to catch & characterize the overflow bug
6083ef5
Tests 1, 2, 3, 6, and 7 fail. I suspect they behave differently with the
`avx2` backend since it depends on where the boundary of the buffer is.
I don't think it's easy to exploit this unless you're trying really
hard. That said, I believe it's possible for sufficiently determined
user code to bypass the MAX_BLOCKS check and generate looped/overflowed
keystream past 256GB.
@jpdoyle
Fix overflow check
e18f443
@jpdoyle
Merge remote-tracking branch 'origin/master' into fix-overflow-check
f3c0824
@jpdoyle
rustfmt
27c4ad6
@jpdoyle
Remove the feature flag that nightly needed
6fe9809
@jpdoyle
32-bit usize exists, unfortunately
36b999c
@jpdoyle
ChaCha20 (legacy,xchacha): Add support for full 64bit-addressed keyst…
9f01d71
…reams
@jpdoyle

jpdoyle commented Jan 8, 2021

Copy link
Copy Markdown
ContributorAuthor

I left the assert!() call that prevents more than 256GB of random number generation in. However, I'm not sure it's necessary, and it seems like the kind of panic that might cause problems downstream.

@tarcieri
tarcieri merged commit 119c9f4 into RustCrypto:masterJan 11, 2021
@tarcieri

tarcieri commented Jan 11, 2021

Copy link
Copy Markdown
Member

Thanks!

@tarcieritarcieri mentioned this pull request Apr 29, 2021
Merged
@tarcieritarcieri mentioned this pull request May 10, 2021
Closed
@jpdoylejpdoyle mentioned this pull request Feb 11, 2025
Closed
Sign up for freeto join this conversation on GitHub. Already have an account? Sign in to comment

Reviewers

No reviews

Assignees

No one assigned

Labels

None yet

Projects

None yet

Milestone

No milestone

Development

Successfully merging this pull request may close these issues.

XChaCha20 unnecessarily limits keystream to 256gb

2 participants

@jpdoyle@tarcieri