First commit for pgpfs

pgpfs.py

@@ -0,0 +1,127 @@
+#!bin/python
+""" pgpfs is a tool to turn your friendly pgp keyserver into a redundant
+persistant filesystem."""
+
+import os
+import sys
+import re
+import base64
+from hashlib import sha256
+import gnupg
+
+os.system('rm -rf gpg')
+GPG = gnupg.GPG(gnupghome='gpg')
+KEYSERVER = 'pgp.mit.edu'
+
+# trial and error lead to this number
+SPLIT_LENGTH = 986
+
+# store file
+
+def read_file_into_list(source_file):
+    """ reads file into list"""
+    with open(source_file, 'r') as source:
+        data = base64.b64encode(source.read())
+        return [data[i:i+SPLIT_LENGTH] for i in range(0, len(data), SPLIT_LENGTH)]
+
+def create_comment(data):
+    """ takes data bit and turns it into a key comment"""
+    checksum = sha256(data).hexdigest()
+    comment = checksum + ' ' + data
+    return comment
+
+def create_key(name):
+    """ creates gpg key out of given data"""
+    input_data = GPG.gen_key_input(
+        key_type='RSA',
+        key_length='1024',
+        name_real='PGP File System',
+        name_comment=create_comment(name),
+        name_email='placeholder@email.address'
+    )
+    return GPG.gen_key(input_data)
+
+def send_key(key_id):
+    """ uploads given key to keyserver"""
+    key_id = str(key_id)
+    GPG.send_keys(KEYSERVER, key_id)
+    if key_id == GPG.search_keys(key_id, KEYSERVER)[0]['keyid']:
+        return key_id
+    else:
+        error = 'Error uploading key ', key_id
+        return error
+
+def store_file(filename1, filename2):
+    """ overall function to upload file to keyserver"""
+    print 'Splitting ', filename1, ' into encoded comments for keys'
+    file_list = read_file_into_list(filename1)
+    output_file = open(filename2, 'w')
+    counter_length = len(file_list)
+    counter = 0
+    for chunk in file_list:
+        print 'Creating key ', counter, ' of ', counter_length
+        counter = counter + 1
+        key_id = create_key(chunk)
+        output_file.write(send_key(key_id)+'\n')
+        print '--> key has been created and uploaded'
+    print 'File has been successfully uploaded to ', KEYSERVER
+
+# fetch file
+
+def get_key_comment(key_id):
+    """ returns comment section of a given key"""
+    return GPG.search_keys(key_id, KEYSERVER)[0]['uids']
+
+def parse_key(key_id):
+    """" parses file bit out of key comment"""
+    comment = get_key_comment(key_id)[0]
+    regex = re.compile(".*?\\((.*?)\\)")
+    comment_bits = re.findall(regex, comment)[0].split(' ')
+    if comment_bits[0] == sha256(comment_bits[1]).hexdigest():
+        return comment_bits[1]
+
+def fetch_file(index_file, filename):
+    """ overall function to fetch component file parts from keyserver"""
+    with open(index_file, 'r') as index, open(filename, 'w+') as download:
+        print 'Fetching keys from ', KEYSERVER, ' to create ', filename
+        fetched_file = ''
+        index_length = len(index.readlines())
+        index.seek(0) # because python is stupid
+        counter = 0
+        for key in index.readlines():
+            print 'Fetching key ', counter, ' of ', index_length
+            counter = counter + 1
+            fetched_file = fetched_file + parse_key(key.rstrip('\n'))
+        print 'All keys have been downloaded'
+        download.write(base64.b64decode(fetched_file))
+        print 'File has been decoded and saved as ', filename
+
+# handle command line input
+
+if len(sys.argv) < 3:
+    print """Usage: ./pgpfs.py [action] filename1 filename2'
+           action can be either ''store'' or ''fetch'''
+
+       When action is 'store':
+           filename1 is the file to upload, filename2 is the name of the key allocation table
+       When action is 'fetch':
+           filename1 is the key allocation table, filename2 is the output file
+
+       Example uses:
+         - To store 'sample.mp3' on the keyserver
+           ./pgpfs.py store sample.mp3 sample.kat
+         - To fetch the file contained in 'sample.kat' and store it as 'sample.mp3'
+           ./pgpfs.py fetch sample.kat sample.mp3
+    """
+    sys.exit(0)
+
+ACTION = sys.argv[1]
+
+if ACTION not in ['store', 'fetch']:
+    print 'Please specific either ''store'' or ''fetch'''
+    sys.exit(0)
+
+if ACTION == 'store':
+    store_file(sys.argv[2], sys.argv[3])
+elif ACTION == 'fetch':
+    fetch_file(sys.argv[2], sys.argv[3])