Linear Search in C

Hit a wall with PicoCTF so I'm taking a break. I found a program for a linear search in C on Programming Simplified:

This gave me the idea for a program that could parse information, store it in structs to categorize it, then later be searched using the Linear Search. The program I came up with doesn't read files only accepts user input:

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#include <stdio.h> #include <stdlib.h> #include <string.h> //Set global variable int totalmembers = 0; //Declare struct and set variables in struct struct file{ char name[30]; char state[4]; char age[3]; }; //Declare single structure within struct as an array struct file members[50]; //Declare function to add members void MemberAdd(void) { int ctr; int addmember = 1; char moremembers[4]; //For loop to store input by user in variables in struct array for (ctr=0; ctr < addmember; ctr++) { printf("Please enter a member\n"); scanf("%s", members[ctr].name); printf("Where does this member live?\n"); scanf("%s", members[ctr].state); printf("What's this member's age?\n"); scanf("%s", members[ctr].age); getchar(); totalmembers++; printf("Do you have more members to input?\n"); scanf("%s", moremembers); if (strcmp(moremembers, "yes")==0) { addmember++; } else { break; } } } int main() { char search[10]; int c; int matches = 0; MemberAdd(); printf("Enter the criteria to search\n"); scanf("%s", search); for (c = 0; c < totalmembers; c++) { //If records are found in struct if ((strcmp(members[c].name, search) == 0) || (strcmp(members[c].state, search) == 0) || (strcmp(members[c].age, search) == 0)) { printf("%s is present in record %d.\n", search, c+1); printf("Record %d: %s %s %s\n", c+1, members[c].name, members[c].state, members[c].age); matches++; } } if (matches == 0) printf("%s is not present in records.\n", search); return 0; }

It's not the prettiest code but, if you substituted the function to take inputs with one that reads files and sticks the relevant info into the structs and switched out the placeholder code for the name, state, and age with whatever categories you needed, I'm thinking you could maybe use it for quick one off analyses and search of results.  Easier said than done but I'm going to try it on some log files.

PicoCTF 2014: Javascrypt

I've been working my way through the challenges up at PicoCTF and thought I'd do a write up on a few of them.  This one is the Javascrypt Challenge worth 40 points.

Here was the challenge:

 Tyrin Robotics Lab uses a special web site to encode their secret messages. Can you determine the value of the secret key?

The hint was:

You may want to learn how to use you browser's JavaScript console.

Naturally I completely missed the hint and did it the hard way my first time around.

The below is the page:

Viewing the source I saw the below:

Completely bypassing the console I decided because I like to do things the hard way I would reconfigure the javascript code to run in C:

This game me a value of 621 making the value answer "flag_621".

For those of you who like to do things the easy way if  you enter:

alert(key)

into the Console it will cause an alert with the value of the key to pop up when you enter a value to encrypt.

Allow Myself to Introduce...

This blog is basically just a place to dump interesting stuff I find about programming, security, whatever.  I'm by no means an expert but I'm working on it day by day.