nikoniko-programming

Monday, December 12, 2011

Certificate error when redirecting http://localhost to https://localhost

On IE, after the certificate error page is shown, clicking "Continue ..." link doesn't work.

"http://localhost" is by default is assigned to "Locked-down Local Machine Zone" by Windows (later than XP SP2)
When "http://localhost/" is redirected to "https://localhost/", IE detect server SSL certificate error and shows an error page.
This error page is internally has URL "res://ieframe.dll/invalidcert.htm?SSLError=50331648#http://localhost/" and is considered to be in "Internet Zone".
"Locked-down Local Machine Zone" by default doesn't allow navigation into its zone from a less privileged zone (e.g. "Internet zone"). Thus clicking continue button is ignored.

Workaround for this problem

Acces "https://localhost/". "https://localhost" is by default considered "Local Intranet zone" thus navigating from "res://ieframe" is possible.
Access "http://127.0.0.1/". "http://127.0.0.1/" is by default considered "Internet zone" thus navigating from "res://ieframe" is possible.
Add "http://localhost" to "Trusted Zone". "Trusted Zone" allows navigation from "Internet Zione" thus navigating from "res://ieframe" is possible.
Using Group policy editor (gpedit.msc), edit User Configuration - Administrative Templates - Windows Components - Internet Explorer - Internet Control Panel - Security Page - Locked-down Local Machine Zone, and set "Web sites in less privileged Web content zones can navigate into this zone" to Enabled (don't forget to set the Options part inside the dialog to "Enabled" too).

Notes: Adding "http://localhost" to "Trusted zone" (or any other zones) internally remove it from "Locked-down Local Machine Zone". If "http://localhost" is afterwards removed from "Trusted zone", it will no longer explicitly bound to any zone and will be considered to belong to "Internet zone". Thus the problem reported here won't reappear after the removal.

Thursday, December 8, 2011

Installing SSL Certificate

Installing certificate on server

Installing certificate on clients

Tuesday, November 29, 2011

MVC custom authorization and jQuery redirect

http://beckelman.net/post/2010/04/01/Custom-ASPNET-MVC-Authorization-Attribute-For-Ajax-Requests.aspx
http://blogs.msdn.com/b/rickandy/archive/2011/05/02/securing-your-asp-net-mvc-3-application.aspx

Tuning jQuery: http://www.artzstudio.com/2009/04/jquery-performance-rules/

Memory leak: http://stackoverflow.com/questions/1462649/jquery-memory-leak-with-dom-removal

Friday, November 18, 2011

Cryptography

Shared-key encryption

c = Enc(key, msg) ----(c)---- msg = Dec(key, c)

Shared-key signature

m,a = h(key, m) ----(m,a)---- m,a =? h(key, m)

Public-key encryption

c = Enc(P-recv, m) ----(c)---- m=Dec(S-recv,m)

Public-key signature

m,a = f(S-send, m) ----(m,a)---- m,a =? g(P-send,m)

Certificate is basically a message signatured by a Certificate Authority (CA)

m,a = f(S-CA, m) ----(m,a)---- m,a =? g(P-CA, m)

SSH see a good summary at http://aperiodic.net/phil/ssh/

Host sends its public key to client for authentication
Key authentication

Client generate public-private key pair
public key is sent to Host
Client doesn't need password anymore (it needs to input passphrase for accessing the private key though)
ssl-agent is used to remember the passphrase so that client can log into host without being asked anything

Sequence for Key authentication

Client connect to Server
Server returns a 'challenge'
Client create an 'authenticator' from the challenge and its private key, and send it back to Server
Server check the 'authenticator' using the Client's public key

SSH-Transport layer uses Key Exchange algorithm

One example is here: http://en.wikipedia.org/wiki/Diffie%E2%80%93Hellman_key_exchange

Jargon of terms: http://identityaccessman.blogspot.com/

Saturday, November 5, 2011

COM and ATL

Converting CComSafeArray to VARIANT

Wednesday, October 12, 2011

Summary of Window Features

http://msdn.microsoft.com/en-us/library/windows/desktop/ms632599(v=vs.85).aspx

Tuesday, October 11, 2011

prototype to jQuery

new Element -> $elem(...)
element.getDimensions() -> $dimensions(element)
element.className = -> $j(element).{has,add,remove}Class
element.addClassName(...) -> $j(element).addClass(...)
element.setStyle(...) -> $j(element).css(...)
element.select(selector) -> $j(selector, element)
$(element).readAttribute(..) -> $j(element).attr(...)
element.show -> $j(element).show()
element.hide -> $j(element).hide()
array.last() -> array[array.length-1]
array.clear() -> array.length=0