Gaganpreet's blog

This content on this page was written a long time ago. It might not be accurate or has opinions which have changed/evolved over time.

Recent Posts

The elusive bug

published on
(Note: This is something that happened earlier this year. A recent discussion reminded me that I should write about it and here it is) Symptoms The bug description wasn’t very helpful. The users couldn’t scroll on their Macs on this one website. Only on a few Macs, not all of them (for one, no one could reproduce this locally). Other operating systems (including iOS) worked fine for them. Other websites scrolled just fine. Read More...

Stripe CTF 3 write up

published on
Stripe CTF 3 finished a few days ago. The latest CTF focussed on distributed systems, instead of security. I have read about distributed systems but getting to develop one was a good learning experience. Unfortunately, it took me a while to solve the last level, and after the capturing the flag I didn’t have time to go back and optimize my code for the other levels. I will walk through my solutions here. Read More...

How secure are Indian payment gateways?

published on
India has a dearth of good payment gateways – most have obsolete difficult-to-use APIs requiring days, if not weeks, to integrate. They require at least a dozen documents (most of them need them sent through post) before they even let you inside their walled garden. Additionally, gateways have complicated plans – depending on your initial spending budget you can get a deal for 3% or otherwise end up paying 5%. Of course, you can also haggle. Read More...

KWallet Security Analysis

published on
KDE 4.12 comes with a KWallet GnuPG backend, which is more secure. More info here, including how to move existing wallets. (Note: Tom Leek has written a more detailed analysis on StackExchange.) I started using KWallet a few months ago to stop reusing same passwords on multiple sites. Using KDE Wallet plugin for Firefox, I setup my passwords to be automatically stored in a KWallet file, which was the best solution I found for Firefox on Linux (other than Lastpass, but it stores passwords remotely and is closed source, which I don’t prefer when dealing with passwords). Read More...

QTreeView and custom filter models

published on
I’ve been learning PySide which is an amazingly easy library to get into GUI development. For an application I was developing, I needed a search filter for some hierarchical data represented by QTreeView. QSortFilterProxyModel is the default choice to add a filter to a QTreeView, but it, by default, applies the filter to all nodes from any root to leaf. If any node has to show up in the search result, all the nodes from a root to that node have to match the search filter, which is mostly useless for hierarchical data. Read More...


Bugs (1)

Computers (3)

Crypto (2)

Felicity (1)

Fun (7)

Funny (4)

Hacking (1)

Health (1)

Howto (1)

Iiit (21)

Internet (2)

Life (16)

Linux (3)

Photography (1)

Python (1)

Scripting (3)

Security (2)

Stumbled (1)

Tech (8)

Tv (1)

Uncategorized (11)


adler (1) anand-buddha-vihar (1) at_fdcwd (1) bash (1) bc (4) blowfish (1) bug (1) bugs (1) cbc (1) ccavenue (1) chmod (1) college (1) coreavc (1) cryptography (1) css (1) ctf (1) ctf3 (1) curl (1) ddos (1) direcpay (1) ebs (1) ecb (1) exam (1) exams (1) faq (1) favorite-stuff (1) february-09 (1) february-2009 (1) felicity (1) felicity-09 (1) ffmpeg (1) firebug (1) firefox (1) form (1) fun (3) funny (4) gaming (1) google (1) goraft (1) h264 (1) hack (1) hmac (1) homeopathic (1) homeopathy (1) howto (1) hsts (1) human-values (1) humor (1) hyderabad (1) iiit (11) iiit-hyderabad (1) incompetence (1) india (1) intervention (1) isas (1) it-crowd (1) jeevan-vidya (1) (1) jv (1) kde (1) kwallet (1) life (5) linux (3) mac-os (1) madwifi (1) md5 (1) medicine (1) microsoft (1) ms-fanboy (1) music (1) night-out (1) opensuse (1) overflow (1) overlay (1) payment-gateways (1) payu (1) payzippy (1) permission-denied (1) photography (1) photography-club (1) pip (1) piss-off (1) pyqt (1) pyside (1) python (1) qdatastream (1) qsortfilterproxymodel (1) qt (1) qtreeview (1) rc4 (1) research (1) rm (1) scripting (1) scroll (1) security (1) server-room (1) sha (1) sha1 (2) sitcom (1) sleep (1) sqlcluster (1) stream (1) streaming (1) stripe (1) stripe-ctf (1) study (1) swine-flu (1) tag-post (1) the-unit (1) transecute (1) tv (1) (1) wallet (1) webcam (1) wifi (1) wikipedia (1) zaakpay (1)