PfUYVaVc

1import os, random, struct
2from Cryptodome.Cipher import AES
3
4
5def encrypt_file(key, input_file):
6    """ Encrypt a file using AES CBC mode.
7
8        key:
9            The encryption key - This is our secret to
10            encrypt and decrypt.
11            Should be 16 (AES-128), 24 (AES-192 ) or
12            32 bytes (AES-256) (characters) long.
13
14        input_file:
15            The input file
16    """
17    
18    # This the block size of data we read, encrypt and write.
19    # It should be a multiple of 16 for AES.
20    chunksize=16*4*1024
21
22    output_filename = input_file + '.aes'
23
24    # 16 random bytes as initialization vector
25    initial_vector = os.urandom(16) # urandom: best method :)
26
27    encryptor = AES.new(key, AES.MODE_CBC, initial_vector)
28    filesize = os.path.getsize(input_file)
29
30    try:
31        with open(input_file, 'rb') as in_file:
32            try:
33                with open(output_filename, 'wb') as out_file:
34                    # put the initial_vector at the beginning of the file
35                    # we need to read from this position to decrypt correctly later
36                    out_file.write(struct.pack('<Q', filesize))
37                    out_file.write(initial_vector)
38
39                    # go block for block through the data
40                    while True:
41                        # read a block of data
42                        chunk = in_file.read(chunksize)
43                        # if chunk == 0, we are at the end
44                        if len(chunk) == 0:
45                            break
46                        # else we need to fill the last block of bytes up to 16
47                        elif len(chunk) % 16 != 0:
48                            chunk += b' ' * (16 - len(chunk) % 16)
49                        # encrypt this block and append it to the file
50                        out_file.write(encryptor.encrypt(chunk))
51            except PermissionError:
52                print("\nCouldn't write ", output_filename)
53    except PermissionError:
54        print("\nCouldn't read ", input_file)
55
56
57def main():
58    #secret_key = b'--> I am a random secret key <--'
59
60    secret_key = input("Give me a secret key (16, 24 or 32 characters):").encode("utf-8")
61    while len(secret_key) != 16 and len(secret_key) != 24 and len(secret_key) != 32:
62        print("\nThere was an error! Please try again with 16, 24 or 32 characters:")
63        secret_key = input("\nGive me a secret key (16, 24 or 32 characters):").encode("utf-8")
64
65    path = input("\nGive me a path or file to encrypt:")
66    while os.path.isdir(path) != True and os.path.isfile(path) != True:
67        print("\nThere was an error! Please try again with a correct path or file to encrypt:")
68        path = input("\nGive me a path or file to encrypt:")
69
70    # path = directory?
71    if os.path.isdir(path):
72        files = []
73        # traverse all subfolders and save path + filename
74        for root, d_names, f_names in os.walk(path):
75            for f in f_names:
76                files.append(os.path.join(root, f))  # these are all files in all subfolders
77        for file in files:
78            # better skip already encrypted files
79            if not file.endswith(".aes"):
80                print("\nEncrypting ", file)
81                encrypt_file(secret_key, file)
82                # after encryption we could delete the file.. ;)
83                # just remove the '#' in the next line
84                #os.remove(file)
85
86    # path is no directory, but must be a file
87    else:
88        # better skip already encrypted files
89        if not path.endswith(".aes"):
90            print("\nEncrypting ", path)
91            encrypt_file(secret_key, path)
92            # after encryption we could delete the file.. ;)
93            # just remove the '#' in the next line
94            #os.remove(path)
95
96if __name__ == '__main__':
97    main()