Keygen

/*
 * Cyber Jawara 2017 - RSA Key generator 2.0
 *
 * gcc rsa_keygen2.c -o rsa_keygen2
 * socat -d -d -d TCP4-LISTEN:41337,reuseaddr,fork EXEC:"./rsa_keygen2" &
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

void rand_str(char *str, size_t len) {
	char cset[] = "0123456789"
              	"abcdefghijklmnopqrstuvwxyz"
              	"ABCDEFGHIJKLMNOPQRSTUVWXYZ";

	while (len-- > 0) {
    	size_t idx = (double) rand() / RAND_MAX * (sizeof cset - 1);
    	*str++ = cset[idx];
	}

	*str = '\0';
}

size_t escape_gets(char *pass, size_t limit) {
	size_t sz;
	char c;
	sz = 0;

	while (sz++ < limit) {
    	c = getchar();
    	if (c == '\n' || c == '\0') {
        	break;
    	} else if (c == '\'') {
        	*pass++ = '\'';
        	*pass++ = '\\';
        	*pass++ = '\'';
        	*pass++ = '\'';
    	} else {
        	*pass++ = c;
    	}
	}

	*pass = '\0';
	return sz;
}

void rsa_keygen() {
	char passphrase[128];
	char private_gen[320];
	char public_gen[320];
	char tmp[128];
	char dir[32];
	size_t len;

	puts("");
	puts(" --//-- CJ RSA Key Generator --//-- ");
	puts("");

	rand_str(dir, 30);
	sprintf(tmp, "mkdir dir/%s 2>/dev/null ", dir);

	passphrase[0] = '\0';
	len = 0;
	while (len < 4) {
    	puts("Passphrase: ");
    	len = escape_gets(passphrase, 127);
    	if (len < 4 || len > 127) {
        	puts("You must type in 4 to 127 characters");
    	}
	}
	puts("");

	system(tmp);

	sprintf(private_gen,
        	"openssl genrsa -aes128 -passout 'pass:%s' -out "
        	"dir/%s/private.pem 2048 2>/dev/null",
        	passphrase, dir);

	sprintf(public_gen,
        	"openssl rsa -passin 'pass:%s' -in dir/%s/private.pem "
        	"-outform PEM -pubout -out dir/%s/public.pem 2>/dev/null",
        	passphrase, dir, dir);

	system(private_gen);
	system(public_gen);

	sprintf(tmp, "cat dir/%s/private.pem 2>/dev/null ", dir);
	system(tmp);
	sprintf(tmp, "cat dir/%s/public.pem 2>/dev/null ", dir);
	system(tmp);
}

void init() {
	char buff[1];
	buff[0] = 0;
	setvbuf(stdout, buff, _IOFBF, 1);
	srand(time(0));
}

int main() {
	init();
	rsa_keygen();
	return 0;
}