developer.intra2net.com Git - python-delta-tar/blob - file_crypt.py

   1 #!/usr/bin/env python3
   2
   3 """ Encrypt a single file
   4
   5 low-cost quick-devel badly-documented
   6
   7 .. codeauthor:: Intra2net <info@intra2net.com>
   8 """
   9
  10 import sys
  11 from deltatar import tarfile
  12 from traceback import print_exc
  13
  14
  15 def main(do_encrypt, in_file, out_file, password, comptype='gz', enctype='aes',
  16          bufsize=tarfile.RECORDSIZE, encoding='UTF-8'):
  17     """ Main function, called when running file as script
  18
  19     see module doc for more info
  20     """
  21
  22     write_handle = read_handle = None
  23     return_code = 4
  24
  25     try:
  26         # open file to read
  27         if do_encrypt:
  28             read_handle = open(in_file, 'rt')
  29         else:
  30             read_handle = tarfile._Stream(name=in_file, mode='r',
  31                                           comptype=comptype, bufsize=bufsize,
  32                                           fileobj=None, enctype=enctype,
  33                                           password=password)
  34         return_code = 3
  35
  36         # open file to write
  37         if do_encrypt:
  38             write_handle = tarfile._Stream(name=out_file, mode='w',
  39                                            comptype=comptype, bufsize=bufsize,
  40                                            fileobj=None, enctype=enctype,
  41                                            password=password)
  42         else:
  43             write_handle = open(out_file, 'wt')
  44         return_code = 1
  45
  46         # convert
  47         while True:
  48             buf = read_handle.read(bufsize)
  49             print('.', end='')
  50             if do_encrypt:
  51                 write_handle.write(buf.encode(encoding, errors='strict'))
  52             else:
  53                 write_handle.write(buf.decode(encoding, errors='replace'))
  54             if len(buf) < bufsize:
  55                 if do_encrypt:
  56                     print('successfully encrypted {} into {}'
  57                           .format(in_file, out_file))
  58                 else:
  59                     print('successfully decrypted {} into {}'
  60                           .format(in_file, out_file))
  61                 break   # reached EOF
  62
  63         return_code = 0
  64
  65     except Exception:
  66         print('error encrypting file')
  67         print_exc()
  68
  69     finally:
  70         # close everything
  71         if write_handle:
  72             try:
  73                 write_handle.close()
  74             except Exception:
  75                 return_code += 8
  76                 print('error closing out file')
  77                 print_exc()
  78
  79         if read_handle:
  80             try:
  81                 read_handle.close()
  82             except Exception:
  83                 return_code += 16
  84                 print('error closing in file')
  85                 print_exc()
  86
  87     # done
  88     return return_code
  89
  90
  91 if __name__ == '__main__':
  92     if len(sys.argv) < 4:
  93         print('file_crypt.py {enc|dec} [-c] INFILE OUTFILE PASSWORD')
  94         sys.exit(2)
  95     elif sys.argv[1] == '-h':
  96         print('encrypt_file.py {enc|dec} [-c] INFILE OUTFILE PASSWORD')
  97         sys.exit(0)
  98
  99     comptype = 'tar'  # auto-detect, not sure whether this would work
 100     idx = 1
 101     if sys.argv[idx] == '-c':
 102         print('assuming gzip compression')
 103         comptype = 'gz'
 104         idx += 1
 105
 106     do_encrypt = None
 107     if sys.argv[idx] == 'enc':
 108         do_encrypt = True
 109     elif sys.argv[idx] == 'dec':
 110         do_encrypt = False
 111     else:
 112         print('encrypt_file.py {enc|dec} [-c] INFILE OUTFILE PASSWORD')
 113         sys.exit(2)
 114
 115     if len(sys.argv) != idx+4:
 116         print('encrypt_file.py {enc|dec} [-c] INFILE OUTFILE PASSWORD')
 117         sys.exit(2)
 118
 119     sys.exit(main(do_encrypt, sys.argv[idx+1], sys.argv[idx+2],
 120                   sys.argv[idx+3], comptype))