[py] Simple file pumper

[dense]

Code: (Python) [Select]

import sys

if len(sys.argv) < 4:
    sys.exit('[-] Missing argument!')

fp = sys.argv[1]
size = int(sys.argv[2])
tp = sys.argv[3]

f = open(fp, 'ab')
if tp == '-kb':
    b_size = size * 1024
elif tp == '-mb':
    b_size = size * 1048576
else:
    sys.exit('[-] Use -mb or -kb!')

bufferSize = 256
for i in range(b_size/bufferSize):
    f.write(str('\0' * bufferSize))

f.close()

print '[+] Finished pumping', fp, 'with', size, tp

Usage:

Code: [Select]

python fpump.py [file] [size] [-mb/-kb]

[Fur]

Won't this throw an OutOfMemoryException (MemoryError?) if b_size is larger than the available RAM?

If so, you could do something like this:

Code: (Python) [Select]

const int BUFFER_SIZE = 256;

int bytesToPump = 1024;

while (bytesToPump > 0) {
   // Write(data, offset, count)
   junkFile.Write(new byte[BUFFER_SIZE], 0, Math.Min(bytesToPump, BUFFER_SIZE));
        bytesToPump -= BUFFER_SIZE;
}
I didn't bother looking for things that could go wrong in the above snippet.

Also, there seems to be a better way of achieving this here.

Oh, and there's no need to put a space before an exclamation mark.

[dense]

Yep, you're right.  Edited the main post.

The stackoverflow solution is faster and cleaner but it's seems it's platform specific. Would the pumped file if transfered from a ntfs system to a fat system be the same (pumped) ? 

[Fur]

Would the pumped file if transfered from a ntfs system to a fat system be the same (pumped) ? 

I don't think so, but I'm not a computer scientist.

Seek and truncate both create sparse files on my system

Because of the File Allocation Table format, sparse files cannot be supported on those filesystems. When data is written at an offset higher than file size, all disk space for lower offsets is allocated, then file size is adjusted.

So truncate and seek create sparse files, but FAT doesn't support sparse files.

[techb]

File pumper? I tried googling it but all the links go to shit like hackforums and other skid crap.

I don't really see a reason to get something like a one line txt to be the size of 500Mb unless you hide code in it, not random bits.

What's the reason?

[Fur]

What's the reason?

Usually to make a file look more legitimate.
Nobody's doing to run avatar.movie.mp4.exe if it's 400 kilobytes.

[googlebot]

the one not running the avatar.mp4.exe of small size is smarter than the one running avatar.mp4.exe which is 700 mb