WHY2/src/lib/encrypter.c
2022-05-24 18:45:44 +02:00

121 lines
2.7 KiB
C

#include <why2/encrypter.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <why2/flags.h>
#include <why2/misc.h>
outputFlags encryptText(char *text, char *keyNew, inputFlags flags)
{
//CHECK FOR ACTIVE VERSION
if (!flags.skipCheck) checkVersion(flags);
//VARIABLES
char *key = malloc(sizeof(char) * getKeyLength());
char *returningText;
char *textBuffer;
int *textKeyChain = malloc(sizeof(int) * strlen(text));
int numberBuffer;
FILE *fileBuffer;
//TRY TO MAKE RANDOM GENERATION REALLY "RANDOM"
fileBuffer = fopen("/dev/urandom", "r");
fread(&numberBuffer, 4, 1, fileBuffer);
srand(numberBuffer);
fclose(fileBuffer);
if (keyNew != NULL)
{
if (strlen(keyNew) < getKeyLength())
{
if (!flags.noOutput) fprintf(stderr, "Key must be at least %d characters long!\n", getKeyLength());
exit(INVALID_KEY);
}
strcpy(key, keyNew);
//REDEFINE keyLength
setKeyLength(strlen(key));
goto skipKey;
}
//LOAD KEY
for (int i = 0; i < getKeyLength(); i++)
{
//SET numberBuffer TO RANDOM NUMBER BETWEEN 0 AND 52
numberBuffer = (rand() % 52) + 1;
//GET CHAR FROM numberBuffer
if (numberBuffer > 26)
{
numberBuffer += 70;
} else
{
numberBuffer += 64;
}
key[i] = (char) numberBuffer;
}
skipKey:
//LOAD textKeyChain
generateTextKeyChain(key, textKeyChain, strlen(text));
//ACTUALLY ENCRYPT TEXT
for (int i = 0; i < strlen(text); i++)
{
textKeyChain[i] -= (int) text[i];
}
//COUNT REQUIRED SIZE FOR returningText
for (int i = 0; i < strlen(text); i++)
{
numberBuffer += countIntLength(textKeyChain[i]);
}
//ALLOCATE returningText (WITH THE SEPARATORS)
returningText = malloc(sizeof(char) * numberBuffer + strlen(text) - 1);
strcpy(returningText, "");
//LOAD returningText
for (int i = 0; i < strlen(text); i++)
{
numberBuffer = sizeof(int) * countIntLength(textKeyChain[i]);
if (i != 0)
{
textBuffer = realloc(textBuffer, numberBuffer);
} else
{
textBuffer = malloc(numberBuffer);
}
sprintf(textBuffer, "%d", textKeyChain[i]);
strcat(returningText, textBuffer);
if (i != strlen(text) - 1)
{
strcat(returningText, ENCRYPTION_SEPARATOR_STRING);
}
}
//LOAD output
outputFlags output =
{
returningText, //ENCRYPTED TEXT
key //GENERATED/USED KEY
};
//DEALLOCATION
free(textKeyChain);
free(textBuffer);
return output;
}