use POSIX qw/strftime/;
use Inline C => Config => LIBS => '-lssl';
use Inline C;
use Time::HiRes qw/clock/;
use strict;
use warnings;

my $start = clock();
print strftime "%T Start\n", localtime(time);
my $key='A';
my $count = 1;
while(1) {
     if(check_key( $key, length $key )) {
         print strftime "%T cracked! key: $key\n", localtime(time);
         last;
     }
    ++$count; ++$key;
}

print "Calcs per second: ", int($count / (clock()-$start)), "\n";

__DATA__
__C__

#include <openssl/rc4.h>;
#define DATALEN 108

unsigned char *crackme = "\xC5\xC4\x44\x22\x0A\xD6\xFB\x08\x97\x27\x92
+\x31\x83"
                         "\x00\xCC\x70\x38\x14\x51\x3E\xE0\x13\xAF\x97
+\xB9\x4F"
                         "\xF9\xAC\xF2\x3F\x9C\x8F\x0E\x74\x8C\x04\xB2
+\xE1\x8B"
                         "\xB5\xA1\xB4\x91\xBB\x73\xE2\x3E\xC9\xA4\x23
+\x3B\x9B"
                         "\xCD\xE4\x85\x4F\xD0\x3D\xCB\xAC\x4B\x3E\x9E
+\xA0\x0F"
                         "\x5B\xF7\xA3\xA1\x19\xB0\xFF\x2E\x66\xC9\xDD
+\x96\xE7"
                         "\xF4\xF0\x97\x29\x59\x08\x26\x01\xAA\x5D\xD2
+\x02\xDF"
                         "\xB0\x50\x39\xCA\x4F\xDC\x28\x05\x17\xE2\x44
+\x35\x36"
                         "\x90\xC0\xDE\x1A";

int check_key ( unsigned char *keystr, int keylen ) {
    RC4_KEY key;
    int i;
    unsigned char buffer[DATALEN];

    RC4_set_key( &key, keylen, keystr );
    RC4( &key, DATALEN, crackme, buffer );

    for( i=0; i<DATALEN; ++i ) {
        if( buffer[i] & ~0x7F ) return 0;
    }
    return 1;
}
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