Posts Tagged “projects”

3 min read

Connect to an Oracle Database using kerberos with python

Jobs failed! Screamed an automatic failure alert in email inbox. Existing python scripts were failing in the server which fetched data from Oracle database. I wondered if the credentials had changed...

Continue reading → kerberos projects python docker oracle database

---

2 min read

Find kth largest element in an array

The other day I stumble upon the question to find the k^th largest element in the array. At first glance, I thought the solution was trivial. But later I thought that there are multiple ways to achieve efficient solution...

Continue reading → algorithm ruby heap max-heap projects

---

1 min read

Encrypted Files in Minix 3

Implemented a new system call in Minix 3 along with the library function that allows it to be called conveniently from a C program. The library interface extends extends file access operations to handle encrypted files.

Reading and writing to a file is done through a system call. The first is to access the "master encryption table" file (/etc/encryptTable) that stores the information about every file that is encrypted within Minix and contains three pieces of information: fs_dev, inode_nr and hashed_pw. The first two information uniquely identifies what file is encrypted and can be obtained from the vnode for the file...

Continue reading → projects minix encrypted-files

---

1 min read

Binary Sempahore

Implemented binary semaphore in Minix 3. Minix 3 is a micro-kernel operating system.

Most of the process pass information among themselves using application IPC. This often result in race condition. To prevent it and provide synchronization, semaphores, first proposed by Dikstras, is used...

Continue reading → projects binary semaphore

---

2 min read

Advanced Encryption Standard (AES)

Advanced Encryption Standard, a symmetric key algorithm, implemented in C++. All the parties use the same key for encryption and decryption. It has superseded DES, another symmetric key algorithms...

Continue reading → projects aes

---

1 min read

Data Encryption Standard (DES)

Data Encryption Standard, a symmetric key algorithm, implemented in C++. All the parties use the same key for encryption and decryption. Look at the diagram below.

Here, m is message which is passed through an encrypted function E along with key K. The resultant is a unintelligent gibberish cipher. The cipher is decoded again using the same key to produce plain message...

Continue reading → projects des

---