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instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all \u003cpre\u003e\u003ccode\u003e blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks"); } } catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); } })(); (function(){ try { var __m = "github.com"; var __re = new RegExp('^' + "github\\.com" + '
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instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

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Readme
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix"); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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instancer
instancer
.dockerignore
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Dockerfile
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README.md
README.md
docker-compose.yml
docker-compose.yml

Repository files navigation

instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

Resources

Readme
Activity

Stars

0 stars

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1 watching

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0 forks
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length \u003e 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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chal
instancer
instancer
.dockerignore
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Dockerfile
Dockerfile
README.md
README.md
docker-compose.yml
docker-compose.yml

Repository files navigation

instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

Resources

Readme
Activity

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0 stars

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1 watching

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0 forks
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
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chal
instancer
instancer
.dockerignore
.dockerignore
Dockerfile
Dockerfile
README.md
README.md
docker-compose.yml
docker-compose.yml

Repository files navigation

instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

Resources

Readme
Activity

Stars

0 stars

Watchers

1 watching

Forks

0 forks
Report repository

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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chal
instancer
instancer
.dockerignore
.dockerignore
Dockerfile
Dockerfile
README.md
README.md
docker-compose.yml
docker-compose.yml

Repository files navigation

instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

Resources

Readme
Activity

Stars

0 stars

Watchers

1 watching

Forks

0 forks
Report repository

Releases

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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chal
instancer
instancer
.dockerignore
.dockerignore
Dockerfile
Dockerfile
README.md
README.md
docker-compose.yml
docker-compose.yml

Repository files navigation

instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

About

yet another CTF challenge instancer

Resources

Readme
Activity

Stars

0 stars

Watchers

1 watching

Forks

0 forks
Report repository

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Languages

, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
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chal
chal
instancer
instancer
.dockerignore
.dockerignore
Dockerfile
Dockerfile
README.md
README.md
docker-compose.yml
docker-compose.yml

Repository files navigation

instancer

Instancer that relies on source-IP based routing for isolation.

  • All instances run a SHARED (privileged) docker container -- we use nested nsjails for instances.
  • Instances each have an isolated network namespace; each instance can bind to the "same" port(s), and services can interact within each instance without affecting other instances and without changing the challenge.
  • Requires --net=host. Maps ports 9000 (instancer) and 7000-7100 (instances) by default.
  • Instances are quickly cleaned up when clients disconenct from the instancer.

How to setup

  • Update the Dockerfile to install your challenge binaries and all dependencies.
  • Update chal/start.sh to start your challenge.
  • Update docker-compose.yml with the following env variables
    • CHALL_INTERNAL_PORT: This should be whatever port your service listens on.
    • CHALL_NUM_SERVERS: Number of simultaneous instances
    • POW_DIFFICULTY: Set to nonzero to enable PoW
    • CHALL_TIMEOUT: Timeout in seconds
  • Optional: Update chal/jail.cfg with your nsjail configuration

How to run

docker-compose up

You should verify that instances are isolated (i.e. that only the source IP that connected to the instancer can connect to the instance), since your network setup may vary.

ADVANCED: Running behind a TCP proxy such as Traefik

Since this instancer relies on source-ip based routing, proxies will break it since the instancer will not be able to see the real source IP.

You can fix this by enabling PROXY2 on your proxy, and setting the ENABLE_PROXY2=1 environment variable.

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yet another CTF challenge instancer

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