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Tweet from Seth Abramson

2017 Jan 22, 5:21
Retweet if you want networks to stop booking Kellyanne Conway, the first U.S. presidential counselor to openly advocate lying to the public.
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Data breakpoints in JavaScript

2016 Jun 17, 5:44

The other day I had to debug a JavaScript UWA that was failing when trying to use an undefined property. In a previous OS build this code would run and the property was defined. I wanted something similar to windbg/cdb's ba command that lets me set a breakpoint on read or writes to a memory location so I could see what was creating the object in the previous OS build and what that code was doing now in the current OS build. I couldn't find such a breakpoint mechanism in Visual Studio or F12 so I wrote a little script to approximate JavaScript data breakpoints.

The script creates a stub object with a getter and setter. It actually performs the get or set but also calls debugger; to break in the debugger. In order to handle my case of needing to break when window.object1.object2 was created or accessed, I further had it recursively set up such stub objects for the matching property names.

Its not perfect because it is an enumerable property and shows up in hasOwnProperty and likely other places. But for your average code that checks for the existence of a property via if (object.property) it works well.

PermalinkCommentsdebug debugging javascript

Windows Store App WebView Cross Origin XMLHttpRequest Behavior

2016 Jun 2, 6:45

TL;DR: Web content in a JavaScript Windows Store app or WebView in a Windows Store app that has full access to WinRT also gets to use XHR unrestricted by cross origin checks.

By default web content in a WebView control in a Windows Store App has the same sort of limitations as that web content in a web browser. However, if you give the URI of that web content full access to WinRT, then the web content also gains the ability to use XMLHttpRequest unrestricted by cross origin checks. This means no CORS checks and no OPTIONS requests. This only works if the web content's URI matches a Rule in the ApplicationContentUriRules of your app's manifest and that Rule declares WindowsRuntimeAccess="all". If it declares WinRT access as 'None' or 'AllowForWebOnly' then XHR acts as it normally does.

In terms of security, if you've already given a page access to all of WinRT which includes the HttpRequest class and other networking classes that don't perform cross origin checks, then allowing XHR to skip CORS doesn't make things worse.

PermalinkCommentsjavascript uwa uwp web webview windows winrt xhr

Tweet from David_Risney

2016 Feb 1, 10:44
Chakra conversions between JavaScript objects and WinRT types: http://deletethis.net/dave/?uri=http%3A%2F%2Fdavescoolblog.blogspot.com%2F2016%2F01%2Fjavascript-types-and-winrt-types.html … I've just updated to note how IPropertySet works.
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Tweet from David_Risney

2016 Jan 7, 9:30
'Works "produced by nature, animals, or plants" cannot be granted copyright protection the US Copyright Office said' http://arstechnica.com/tech-policy/2016/01/judge-says-monkey-cannot-own-copyright-to-famous-selfies/ …
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Tweet from David_Risney

2016 Jan 6, 10:53
Cracking passwords with neural networks https://0day.work/using-neural-networks-for-password-cracking/ …
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Retweet of FTC

2015 Nov 15, 4:40
Cross-Device Tracking workshop introductory remarks by FTC Chairwoman @EdithRamirezFTC. Watch live: https://kvgo.com/ftc/11-16-2015-Cross-Device-Tracking … #FTCXDT
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Retweet of jvaleski

2015 Nov 9, 2:38
Just had "the talk" w/ my daughter; complete w/ diagram. Everyone needs to know how this all works. #thenetwork pic.twitter.com/4vOV4d6XfY
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Retweet of FTC

2015 Nov 4, 6:03
Our #StartWithSecurity workshop starts now. Watch live: https://player.streamspot.com/simple/live.php?cn=f9a676ee&aspect=true&w=1280&h=720&noArchiveBtn=true&noLiveBtn=true … Agenda: https://www.ftc.gov/news-events/events-calendar/2015/11/start-security-austin …
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Tweet from David_Risney

2015 Oct 12, 9:31
Auto generating clickbait articles via neural network: http://larseidnes.com/2015/10/13/auto-generating-clickbait-with-recurrent-neural-networks/ …. And the result: http://clickotron.com/ 
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Tweet from David_Risney

2015 Jul 21, 12:13
I always thought BSG's Galactica disallowing networks and air gapping everything was lame. Starting to get it now.
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99percentinvisible:Rainworks: art that only appears in rain.

2015 Mar 24, 12:04








99percentinvisible:

Rainworks: art that only appears in rain.

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99percentinvisible:Rainworks: art that only appears in rain.

2015 Mar 24, 12:04








99percentinvisible:

Rainworks: art that only appears in rain.

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Polygon: Ready Player One sequel in the works, says movie screenwriter

2015 Jan 16, 3:00
Polygon        ✔ @Polygon :
Ready Player One sequel in the works, says movie screenwriter http://polygon.com/e/7324396  pic.twitter.com/aOKU3hm5p5
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The Doritos origin story: Repurposed garbage from Disneyland

2014 May 6, 7:16

shortformblog:

A reminder that those Doritos you love are trash:

Shortly after Disneyland opened in 1955, the founder of Frito-Lay got permission from Walt Disney to open a restaurant in Frontierland with a Mexican-ish theme. “Casa de Fritos” was, unsurprisingly, all about the Fritos. Customers got free Fritos, and Fritos were incorporated into many of the dishes. Fritos were dispensed by an animatronic vending machine that featured the terrifying “Frito Kid”asking his assistant “Klondike” to bring the bag up from a mineshaft. I guess the conceit is that Fritos were mined by Forty-Niners?

Casa de Fritos contracted their tortilla production to a company called Alex Foods. One of the salesmen from Alex Foods, making a delivery to Casa de Fritos, noticed stale tortillas in the garbage and gave the cook a little tip: fry them and sell them as chips instead of throwing them away. Casa de Fritos began making these fried, seasoned chips to enormous success, but didn’t report this new menu item to the Frito-Lay company.

Eventually Frito-Lay found out what they were doing with the chips, packaged them, and sold them by the truckload. See, dumpster diving works out sometimes!

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picjumbo

2014 Jan 5, 2:22
/wp-content/uploads/IMG_3811-1300x866.jpg"/>

picjumbo

totally free photos for your commercial & personal works

 

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URI functions in Windows Store Applications

2013 Jul 25, 1:00

Summary

The Modern SDK contains some URI related functionality as do libraries available in particular projection languages. Unfortunately, collectively these APIs do not cover all scenarios in all languages. Specifically, JavaScript and C++ have no URI building APIs, and C++ additionally has no percent-encoding/decoding APIs.
WinRT (JS and C++)
JS Only
C++ Only
.NET Only
Parse
 
Build
Normalize
Equality
 
 
Relative resolution
Encode data for including in URI property
Decode data extracted from URI property
Build Query
Parse Query
The Windows.Foudnation.Uri type is not projected into .NET modern applications. Instead those applications use System.Uri and the platform ensures that it is correctly converted back and forth between Windows.Foundation.Uri as appropriate. Accordingly the column marked WinRT above is applicable to JS and C++ modern applications but not .NET modern applications. The only entries above applicable to .NET are the .NET Only column and the WwwFormUrlDecoder in the bottom left which is available to .NET.

Scenarios

Parse

This functionality is provided by the WinRT API Windows.Foundation.Uri in C++ and JS, and by System.Uri in .NET.
Parsing a URI pulls it apart into its basic components without decoding or otherwise modifying the contents.
var uri = new Windows.Foundation.Uri("http://example.com/path%20segment1/path%20segment2?key1=value1&key2=value2");
console.log(uri.path);// /path%20segment1/path%20segment2

WsDecodeUrl (C++)

WsDecodeUrl is not suitable for general purpose URI parsing.  Use Windows.Foundation.Uri instead.

Build (C#)

URI building is only available in C# via System.UriBuilder.
URI building is the inverse of URI parsing: URI building allows the developer to specify the value of basic components of a URI and the API assembles them into a URI. 
To work around the lack of a URI building API developers will likely concatenate strings to form their URIs.  This can lead to injection bugs if they don’t validate or encode their input properly, but if based on trusted or known input is unlikely to have issues.
            Uri originalUri = new Uri("http://example.com/path1/?query");
            UriBuilder uriBuilder = new UriBuilder(originalUri);
            uriBuilder.Path = "/path2/";
            Uri newUri = uriBuilder.Uri; // http://example.com/path2/?query

WsEncodeUrl (C++)

WsEncodeUrl, in addition to building a URI from components also does some encoding.  It encodes non-US-ASCII characters as UTF8, the percent, and a subset of gen-delims based on the URI property: all :/?#[]@ are percent-encoded except :/@ in the path and :/?@ in query and fragment.
Accordingly, WsEncodeUrl is not suitable for general purpose URI building.  It is acceptable to use in the following cases:
- You’re building a URI out of non-encoded URI properties and don’t care about the difference between encoded and decoded characters.  For instance you’re the only one consuming the URI and you uniformly decode URI properties when consuming – for instance using WsDecodeUrl to consume the URI.
- You’re building a URI with URI properties that don’t contain any of the characters that WsEncodeUrl encodes.

Normalize

This functionality is provided by the WinRT API Windows.Foundation.Uri in C++ and JS and by System.Uri in .NET.  Normalization is applied during construction of the Uri object.
URI normalization is the application of URI normalization rules (including DNS normalization, IDN normalization, percent-encoding normalization, etc.) to the input URI.
        var normalizedUri = new Windows.Foundation.Uri("HTTP://EXAMPLE.COM/p%61th foo/");
        console.log(normalizedUri.absoluteUri); // http://example.com/path%20foo/
This is modulo Win8 812823 in which the Windows.Foundation.Uri.AbsoluteUri property returns a normalized IRI not a normalized URI.  This bug does not affect System.Uri.AbsoluteUri which returns a normalized URI.

Equality

This functionality is provided by the WinRT API Windows.Foundation.Uri in C++ and JS and by System.Uri in .NET. 
URI equality determines if two URIs are equal or not necessarily equal.
            var uri1 = new Windows.Foundation.Uri("HTTP://EXAMPLE.COM/p%61th foo/"),
                uri2 = new Windows.Foundation.Uri("http://example.com/path%20foo/");
            console.log(uri1.equals(uri2)); // true

Relative resolution

This functionality is provided by the WinRT API Windows.Foundation.Uri in C++ and JS and by System.Uri in .NET 
Relative resolution is a function that given an absolute URI A and a relative URI B, produces a new absolute URI C.  C is the combination of A and B in which the basic components specified in B override or combine with those in A under rules specified in RFC 3986.
        var baseUri = new Windows.Foundation.Uri("http://example.com/index.html"),
            relativeUri = "/path?query#fragment",
            absoluteUri = baseUri.combineUri(relativeUri);
        console.log(baseUri.absoluteUri);       // http://example.com/index.html
        console.log(absoluteUri.absoluteUri);   // http://example.com/path?query#fragment

Encode data for including in URI property

This functionality is available in JavaScript via encodeURIComponent and in C# via System.Uri.EscapeDataString. Although the two methods mentioned above will suffice for this purpose, they do not perform exactly the same operation.
Additionally we now have Windows.Foundation.Uri.EscapeComponent in WinRT, which is available in JavaScript and C++ (not C# since it doesn’t have access to Windows.Foundation.Uri).  This is also slightly different from the previously mentioned mechanisms but works best for this purpose.
Encoding data for inclusion in a URI property is necessary when constructing a URI from data.  In all the above cases the developer is dealing with a URI or substrings of a URI and so the strings are all encoded as appropriate. For instance, in the parsing example the path contains “path%20segment1” and not “path segment1”.  To construct a URI one must first construct the basic components of the URI which involves encoding the data.  For example, if one wanted to include “path segment / example” in the path of a URI, one must percent-encode the ‘ ‘ since it is not allowed in a URI, as well as the ‘/’ since although it is allowed, it is a delimiter and won’t be interpreted as data unless encoded.
If a developer does not have this API provided they can write it themselves.  Percent-encoding methods appear simple to write, but the difficult part is getting the set of characters to encode correct, as well as handling non-US-ASCII characters.
        var uri = new Windows.Foundation.Uri("http://example.com" +
            "/" + Windows.Foundation.Uri.escapeComponent("path segment / example") +
            "?key=" + Windows.Foundation.Uri.escapeComponent("=&?#"));
        console.log(uri.absoluteUri); // http://example.com/path%20segment%20%2F%20example?key=%3D%26%3F%23

WsEncodeUrl (C++)

In addition to building a URI from components, WsEncodeUrl also percent-encodes some characters.  However the API is not recommend for this scenario given the particular set of characters that are encoded and the convoluted nature in which a developer would have to use this API in order to use it for this purpose.
There are no general purpose scenarios for which the characters WsEncodeUrl encodes make sense: encode the %, encode a subset of gen-delims but not also encode the sub-delims.  For instance this could not replace encodeURIComponent in a C++ version of the following code snippet since if ‘value’ contained ‘&’ or ‘=’ (both sub-delims) they wouldn’t be encoded and would be confused for delimiters in the name value pairs in the query:
"http://example.com/?key=" + Windows.Foundation.Uri.escapeComponent(value)
Since WsEncodeUrl produces a string URI, to obtain the property they want to encode they’d need to parse the resulting URI.  WsDecodeUrl won’t work because it decodes the property but Windows.Foundation.Uri doesn’t decode.  Accordingly the developer could run their string through WsEncodeUrl then Windows.Foundation.Uri to extract the property.

Decode data extracted from URI property

This functionality is available in JavaScript via decodeURIComponent and in C# via System.Uri.UnescapeDataString. Although the two methods mentioned above will suffice for this purpose, they do not perform exactly the same operation.
Additionally we now also have Windows.Foundation.Uri.UnescapeComponent in WinRT, which is available in JavaScript and C++ (not C# since it doesn’t have access to Windows.Foundation.Uri).  This is also slightly different from the previously mentioned mechanisms but works best for this purpose.
Decoding is necessary when extracting data from a parsed URI property.  For example, if a URI query contains a series of name and value pairs delimited by ‘=’ between names and values, and by ‘&’ between pairs, one must first parse the query into name and value entries and then decode the values.  It is necessary to make this an extra step separate from parsing the URI property so that sub-delimiters (in this case ‘&’ and ‘=’) that are encoded will be interpreted as data, and those that are decoded will be interpreted as delimiters.
If a developer does not have this API provided they can write it themselves.  Percent-decoding methods appear simple to write, but have some tricky parts including correctly handling non-US-ASCII, and remembering not to decode .
In the following example, note that if unescapeComponent were called first, the encoded ‘&’ and ‘=’ would be decoded and interfere with the parsing of the name value pairs in the query.
            var uri = new Windows.Foundation.Uri("http://example.com/?foo=bar&array=%5B%27%E3%84%93%27%2C%27%26%27%2C%27%3D%27%2C%27%23%27%5D");
            uri.query.substr(1).split("&").forEach(
                function (keyValueString) {
                    var keyValue = keyValueString.split("=");
                    console.log(Windows.Foundation.Uri.unescapeComponent(keyValue[0]) + ": " + Windows.Foundation.Uri.unescapeComponent(keyValue[1]));
                    // foo: bar
                    // array: ['','&','=','#']
                });

WsDecodeUrl (C++)

Since WsDecodeUrl decodes all percent-encoded octets it could be used for general purpose percent-decoding but it takes a URI so would require the dev to construct a stub URI around the string they want to decode.  For example they could prefix “http:///#” to their string, run it through WsDecodeUrl and then extract the fragment property.  It is convoluted but will work correctly.

Parse Query

The query of a URI is often encoded as application/x-www-form-urlencoded which is percent-encoded name value pairs delimited by ‘&’ between pairs and ‘=’ between corresponding names and values.
In WinRT we have a class to parse this form of encoding using Windows.Foundation.WwwFormUrlDecoder.  The queryParsed property on the Windows.Foundation.Uri class is of this type and created with the query of its Uri:
    var uri = Windows.Foundation.Uri("http://example.com/?foo=bar&array=%5B%27%E3%84%93%27%2C%27%26%27%2C%27%3D%27%2C%27%23%27%5D");
    uri.queryParsed.forEach(
        function (pair) {
            console.log("name: " + pair.name + ", value: " + pair.value);
            // name: foo, value: bar
            // name: array, value: ['','&','=','#']
        });
    console.log(uri.queryParsed.getFirstValueByName("array")); // ['','&','=','#']
The QueryParsed property is only on Windows.Foundation.Uri and not System.Uri and accordingly is not available in .NET.  However the Windows.Foundation.WwwFormUrlDecoder class is available in C# and can be used manually:
            Uri uri = new Uri("http://example.com/?foo=bar&array=%5B%27%E3%84%93%27%2C%27%26%27%2C%27%3D%27%2C%27%23%27%5D");
            WwwFormUrlDecoder decoder = new WwwFormUrlDecoder(uri.Query);
            foreach (IWwwFormUrlDecoderEntry entry in decoder)
            {
                System.Diagnostics.Debug.WriteLine("name: " + entry.Name + ", value: " + entry.Value);
                // name: foo, value: bar
                // name: array, value: ['','&','=','#']
            }
 

Build Query

To build a query of name value pairs encoded as application/x-www-form-urlencoded there is no WinRT API to do this directly.  Instead a developer must do this manually making use of the code described in “Encode data for including in URI property”.
In terms of public releases, this property is only in the RC and later builds.
For example in JavaScript a developer may write:
            var uri = new Windows.Foundation.Uri("http://example.com/"),
                query = "?" + Windows.Foundation.Uri.escapeComponent("array") + "=" + Windows.Foundation.Uri.escapeComponent("['','&','=','#']");
 
            console.log(uri.combine(new Windows.Foundation.Uri(query)).absoluteUri); // http://example.com/?array=%5B'%E3%84%93'%2C'%26'%2C'%3D'%2C'%23'%5D
 
PermalinkCommentsc# c++ javascript technical uri windows windows-runtime windows-store

Subtleties of postMessage

2013 Jul 15, 1:00

In IE10 and other new browsers one may create MessageChannel objects that have two MessagePorts each connected (w3c spec calls it entangled) to one another such that postMessage on one port results in the message event firing on the other. You can pass an array of ports as the last parameter to postMessage and they show up in the ports property of the message event arg.

Origin

The postMessage here is like the worker postMessage and unlike the window and iframe postMessage in that it applies no origin checking:

  1. No origin postMessage in workers and MessagePorts: postMessage(messageData, ports)
  2. Origin postMessage in windows and iframes: postMessage(messageData, targetOrigin, ports)

Unfortunately the origin isn't an optional parameter at the end to make the two postMessages have the same signature.

On the event handler side, the event arg always has an origin property. But in the no origin case it is always the empty string.

Source

There is also a source property on the message event arg which if set is an object that has a postMessage property allowing you to post back to your caller. It is set for the origin case, however, in the no origin case this property is null. This is somewhat reasonable because in the case of MessagePort and Workers there are only two endpoints so you always know the source of a message implicitly. Unlike the origin case in which any iframe or window can be calling postMessage on any other iframe or window and the caller is unknown. So not unreasonable but it would be nice if the source property was always set for consistency.

MessageChannel start

When a MessageChannel is created it has two MessagePorts, but until those ports are started they will queue up any messages they receive. Once started they will dispatch all queued messages. Ports don't have to be started to send messages.

A port may be started in two ways, either by explicitly calling the start method on the port, or by setting the onmessage callback property on the port. However, adding an event listener via addEventListener("message", does not start the port. It works this way in IE and Chrome and the spec states this as well.

The justification is that since you can have only one callback via onmessage that once set you must implicitly be ready to receive messages and its fine to start the port. As opposed to the addEventListener in which case the user agent cannot start implicitly because it doesn't know how many event listeners will be added.  I found Hixie stating this justification in geoloc meeting notes.

Links

W3C Spec

Opera introduction

PermalinkCommentsDOM html javascript postMessage technical web-worker worker

The Lucille Bluth/Mitt Romney Tumblr confirms that saying awful rich person things is all about context

2012 Sep 24, 7:33

Mitt Romney quotes on screen shots of Lucille from Arrested Development works surprisingly well.

PermalinkCommentshumor arrested-development mitt-Romney politics

Brainfuck beware: JavaScript is after you! | Patricio Palladino

2012 Aug 10, 10:18

“tl;dr I just made a tool to transform any javascript code into an equivalent sequence of ()[]{}!+ characters. You can try it here, or grab it from github or npm. Keep on reading if you want to know how it works.”

JavaScript has some crazy implicit casts.

PermalinkCommentstechnical humor programming javascript obfuscation
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