uri - Dave's Blog


Detect login with CSP - When Security Generates Insecurity

23 days ago

An interesting way to use the report-uri feature of CSP to detect if a user is logged into Google, Facebook etc.

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From Inside Edward Snowden’s Life as a Robot: Wizner had...

Jun 23, 7:04

From Inside Edward Snowden’s Life as a Robot:

Wizner had to jump on a phone call during a meeting with his whistleblower client. When he got off the phone, he found that Snowden had rolled the bot into civil liberties lawyer Jameel Jaffer’s office and was discussing the 702 provision of the Foreign Intelligence Surveillance Act. “It was kind of cool,” Wizner says.

It is neat but they’re marketing video is at times strangely terrifying. Put different music on when the Susan-bot comes up behind the unknowing Mark and this could be a horror movie trailer.

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On exploiting security issues in botnet C&C...

Jun 23, 4:26

On exploiting security issues in botnet C&C software:

Hackers “are learning that it’s not so easy to write secure code,” Toro says. “Most of us in the business of securing our applications and systems know that bulletproofing software is an extremely expensive and exhaustive undertaking. Malware creators who have to look to their own defences would have to slow down the production of new attacks.”

FYI, if you want to know what it looks like when you hack a hacker, look no further than the seminal 1995 film Hackers.

PermalinkCommentstechnical security

U.S. Marshals Seize Cops’ Spying Records to Keep Them From the ACLU | Threat Level | WIRED

Jun 4, 6:08

"A routine request in Florida for records detailing the use of a surveillance tool known as stingray turned extraordinary Tuesday when the U.S. Marshals Service seized the documents before local police could release them."

Also what about the part where the PD reveals that its been using the stingray a bunch without telling any court and blames that on the manufacturer’s NDA.

PermalinkCommentstechnical law security phone

XSS game

May 29, 1:10

Google’s XSS training game. Learn how to find XSS issues for fun and profit.

PermalinkCommentstechnical web security xss google

location.hash and location.search are bad and they should feel bad

May 22, 9:25
The DOM location interface exposes the HTML document's URI parsed into its properties. However, it is ancient and has problems that bug me but otherwise rarely show up in the real world. Complaining about mostly theoretical issues is why blogging exists, so here goes:
  • The location object's search, hash, and protocol properties are all misnomers that lead to confusion about the correct terms:
    • The 'search' property returns the URI's query property. The query property isn't limited to containing search terms.
    • The 'hash' property returns the URI's fragment property. This one is just named after its delimiter. It should be called the fragment.
    • The 'protocol' property returns the URI's scheme property. A URI's scheme isn't necessarily a protocol. The http URI scheme of course uses the HTTP protocol, but the https URI scheme is the HTTP protocol over SSL/TLS - there is no HTTPS protocol. Similarly for something like mailto - there is no mailto wire protocol.
  • The 'hash' and 'search' location properties both return null in the case that their corresponding URI property doesn't exist or if its the empty string. A URI with no query property and a URI with an empty string query property that are otherwise the same, are not equal URIs and are allowed by HTTP to return different content. Similarly for the fragment. Unless the specific URI scheme defines otherwise, an empty query or hash isn't the same as no query or hash.
But like complaining about the number of minutes in an hour none of this can ever change without huge compat issues on the web. Accordingly I can only give my thanks to Anne van Kesteren and the awesome work on the URL standard moving towards a more sane (but still working practically within the constraints of compat) location object and URI parsing in the browser.

URI Design and Ownership - IETF Draft

May 21, 2:06

URI Design & Ownership - On the issues with and alternatives to requiring well known filenames and extensions in URIs. You must love the draft’s URI.

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Encrypted Web Traffic More Than Doubles

May 18, 1:20

RT @PeerProd In Europe, encrypted traffic went from 1.47% to 6.10%, and in Latin America, it increased from 1.8% to 10.37%
http://www.wired.com/2014/05/sandvine-report/ #NSA

PermalinkCommentstechnical security nsa encryption


Apr 29, 8:27

Does it betray my innocence that I’m shocked by the amount of exec($_GET you can easily find on github? Hilarious comment thread on hacker news: 

This is awful. Shell commands are not guaranteed to be idempotent, people! These should all be of the form exec($_POST, not exec($_GET.


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The 5 Things To Do About the New Heartbleed Bug

Apr 9, 9:06

Its time to get a password manager.

PermalinkCommentssecurity password technical

Hijacking user sessions with the Heartbleed vulnerability · Matt's Life Bytes

Apr 8, 6:36

Just a quick tutorial on exploiting heartbleed for session hijacking. Is it worse to use https than http today?

PermalinkCommentstechnical security ssl heartbleed session-hijack

Xbox One Sign Out Trolling - YouTube

Jan 8, 5:53PermalinkCommentsvideo game xbox voice security

laughingsquid: F.A.A. Lifts Restrictions on Electronics During...

2013 Oct 31, 4:57


F.A.A. Lifts Restrictions on Electronics During All Phases of Flight

PermalinkCommentsflight plane electronics faa

theatlantic: Victorian Trolling: How Con Artists Spammed in a...

2013 Oct 29, 7:42


Victorian Trolling: How Con Artists Spammed in a Time Before Email

The main difference between 21st-century scams and those of centuries past is one of delivery method.

Read more. [Image: Wikimedia Commons/Benjamin Breen]

PermalinkCommentshistory spam technical humor internet

FitBit and WebOC Application Compatibility Errors

2013 Aug 29, 7:17
I just got a FitBit One from my wife. Unfortunately I had issues running their app on my Windows 8.1 Preview machine. But I recognized the errors as IE compatibility issues, for instance an IE dialog popup from the FitBit app telling me about an error in the app's JavaScript. Given my previous post on WebOC versioning you may guess what I tried next. I went into the registry and tried out different browser mode and document mode versions until I got the FitBit software running without error. Ultimately I found the following registry value to work well ('FitBit connect.exe' set to DWORD decimal 8888).
Windows Registry Editor Version 5.00

"Fitbit Connect.exe"=dword:000022b8

For those familiar with the Windows registry the above should be enough. For those not familiar, copy and paste the above into notepad, save as a file named "fitbit.reg", and then double click the reg file and say 'Yes' to the prompt. Hopefully in the final release of Windows 8.1 this won't be an issue.

Pixel Perfect Timing Attacks with HTML5 - Context » Information Security

2013 Aug 7, 8:25PermalinkCommentssecurity html html5 svg javascript requestAnimationFrame iframe

URI functions in Windows Store Applications

2013 Jul 25, 1:00


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
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.



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.


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.


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

In Depth Review: New NSA Documents Expose How Americans Can Be Spied on Without A Warrant

2013 Jun 21, 10:43

What It All Means: All Your Communications are Belong to U.S. In sum, if you use encryption they’ll keep your data forever. If you use Tor, they’ll keep your data for at least five years. If an American talks with someone outside the US, they’ll keep your data for five years. If you’re talking to your attorney, you don’t have any sense of privacy. And the NSA can hand over you information to the FBI for evidence of any crime, not just terrorism. All without a warrant or even a specific FISA order.

Not sure if this is saying all Tor data is collected or saying if someone uses Tor then start collecting that someone’s communication.

PermalinkCommentstechnical legal tor nsa eff spying security privacy

Microsoft will pay up to $100K for new Windows exploit techniques

2013 Jun 21, 4:29

Good news everyone! Of course Microsoft employees are not eligible but that’s probably for the best.

PermalinkCommentssecurity exploit money microsoft technical

wilwheaton: owlturdcomix: Thoughts I have instead of smart...

2013 May 13, 2:31



Thoughts I have instead of smart thoughts.


Owl Turd is rapidly becoming one of my favourite webcomics.

This may have been a Serial Experiments Lain episode synopsis.

PermalinkCommentshumor map
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