commit 038c8f7c215ea1fcf32c61cd76f0ff80f4bb7990 Author: David Fifield <david@bamsoftware.com> Date: Sun Oct 16 19:12:11 2011 -0700 Add flashproxy.js. This is a file that will be hosted at crypto.stanford.edu to make it easy to install the badge on a web page. This script also does the User-Agent detection (to politely disable itself for cell phones) that was formerly done by swfcat itself. --- README | 12 +++--- flashproxy.js | 141 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 147 insertions(+), 6 deletions(-) diff --git a/README b/README index 1a49686..6db4ee0 100644 --- a/README +++ b/README @@ -150,13 +150,13 @@ wait a few minutes. It can take a while to download relay descriptors. == How to put a flash proxy badge on a web page. -Copy swfcat.swf to your server, then paste in this HTML: +Copy swfcat.swf to your server, then paste in this HTML where you want +the badge to appear: + +<script type="text/javascript" src="https://crypto.stanford.edu/flashproxy/flashproxy.js"></script> + +It will be inserted as a span element with the id "flashproxy-badge". -<object width="70" height="23"> - <param name="movie" value="swfcat.swf"> - <param name="flashvars" value=""> - <embed src="swfcat.swf" width="70" height="23" flashvars=""></embed> -</object> == For developers diff --git a/flashproxy.js b/flashproxy.js new file mode 100644 index 0000000..fea72f9 --- /dev/null +++ b/flashproxy.js @@ -0,0 +1,141 @@ +/* Are circumstances such that we should self-disable and not be a + proxy? We take a best-effort guess as to whether this device runs on + a battery or the data transfer might be expensive. + + Matching mobile User-Agents is complex; but we only need to match + those devices that can also run a recent version of Adobe Flash, + which is a subset of this list: + https://secure.wikimedia.org/wikipedia/en/wiki/Adobe_Flash_Player#Mobile_ope... + + Other resources: + http://www.zytrax.com/tech/web/mobile_ids.html + http://googlewebmastercentral.blogspot.com/2011/03/mo-better-to-also-detect-... + http://search.cpan.org/~cmanley/Mobile-UserAgent-1.05/lib/Mobile/UserAgent.p... +*/ +function flashproxy_should_disable() +{ + var ua; + + ua = window.navigator.userAgent; + if (ua != null) { + const UA_LIST = [ + /\bmobile\b/i, + /\bandroid\b/i, + /\bopera mobi\b/i, + ]; + + for (var i = 0; i < UA_LIST.length; i++) { + var re = UA_LIST[i]; + + if (ua.match(re)) { + return true; + } + } + } + + return false; +} + +/* Create and return a DOM fragment: +<span id=BADGE_ID> +<a href=FLASHPROXY_INFO_URL> + child +</a> +</span> +*/ +function flashproxy_make_container(child) +{ + const BADGE_ID = "flashproxy-badge"; + const FLASHPROXY_INFO_URL = "https://crypto.stanford.edu/flashproxy/"; + + var container; + var a; + + container = document.createElement("span"); + container.setAttribute("id", "flashproxy-badge"); + a = document.createElement("a"); + a.setAttribute("href", FLASHPROXY_INFO_URL); + a.appendChild(child) + container.appendChild(a); + + return container; +} + +/* Create and return a DOM fragment: +<object width=WIDTH height=HEIGHT> + <param name="movie" value=SWFCAT_URL> + <param name="flashvars" value=FLASHVARS> + <embed src=SWFCAT_URL width=WIDTH height=HEIGHT flashvars=FLASHVARS></embed> +</object> +*/ +function flashproxy_make_badge() +{ + const WIDTH = 70; + const HEIGHT = 23; + const FLASHVARS = ""; + const SWFCAT_URL = "https://crypto.stanford.edu/flashproxy/swfcat.swf"; + + var object; + var param; + var embed; + + object = document.createElement("object"); + object.setAttribute("width", WIDTH); + object.setAttribute("height", HEIGHT); + + param = document.createElement("param"); + param.setAttribute("name", "movie"); + param.setAttribute("value", SWFCAT_URL); + object.appendChild(param); + param = document.createElement("param"); + param.setAttribute("name", "flashvars"); + param.setAttribute("value", FLASHVARS); + object.appendChild(param); + + embed = document.createElement("embed"); + embed.setAttribute("src", SWFCAT_URL); + embed.setAttribute("width", WIDTH); + embed.setAttribute("height", HEIGHT); + embed.setAttribute("flashvars", FLASHVARS); + object.appendChild(embed); + + return object; +} + +/* Create and return a non-functional placeholder badge DOM fragment: + <img src=BADGE_IMAGE_URL border="0"> +*/ +function flashproxy_make_dummy_badge() +{ + const BADGE_IMAGE_URL = "https://crypto.stanford.edu/flashproxy/badge.png"; + + var img; + + img = document.createElement("img"); + img.setAttribute("src", BADGE_IMAGE_URL); + img.setAttribute("border", 0); + + return img; +} + +function flashproxy_badge_insert() +{ + var badge; + var e; + + if (flashproxy_should_disable()) { + badge = flashproxy_make_dummy_badge(); + } else { + badge = flashproxy_make_badge(); + } + + /* http://intertwingly.net/blog/2006/11/10/Thats-Not-Write for this trick to + insert right after the <script> element in the DOM. */ + e = document; + while (e.lastChild && e.lastChild.nodeType == 1) { + e = e.lastChild; + } + e.parentNode.appendChild(flashproxy_make_container(badge)); +} + +flashproxy_badge_insert();