Using the `cipher` command (with examples)

The cipher command is a powerful tool in Windows that allows users to display or alter the encryption of directories and files on NTFS volumes. This command is especially useful for managing file and directory encryption in a secure and efficient manner. In this article, we will explore the different use cases of the cipher command and provide code examples for each case.

Display information about a specific encrypted file or directory

To display information about a specific encrypted file or directory, you can use the following code:

cipher /c:path\to\file_or_directory

Motivation: This command is useful when you need to check if a file or directory is encrypted and view its encryption status. It provides detailed information about the encryption algorithm used, number of encrypted files, and many other properties.

Explanation: The /c option is used to display information about an encrypted file or directory. The path\to\file_or_directory argument specifies the file or directory you want to display information about.

Example Output: Here is an example output of the cipher /c command:

Listing Directory: C:\path\to\file_or_directory
New files added to this directory will be encrypted.

     P  C:\path\to\file_or_directory\example.txt
        [file is not in use]

     P  C:\path\to\file_or_directory\subdirectory
        [Directory]
        $SDSData: F26B22129F5384B3FB637ED71918972E
        CE561576B048ADCD143D30

Encrypted Directory: C:\path\to\file_or_directory
  (DIR)  C:\path\to\file_or_directory

Encrypted File(s):    1
  (F)  C:\path\to\file_or_directory\example.txt

Encrypt a file or directory

To encrypt a file or directory, you can use the following code:

cipher /e:path\to\file_or_directory

Motivation: Encrypting sensitive files or directories adds an extra layer of security to protect them from unauthorized access. This command is useful when you want to encrypt specific files or directories to safeguard sensitive information.

Explanation: The /e option is used to encrypt a file or directory. The path\to\file_or_directory argument specifies the file or directory you want to encrypt.

Example Output: After encrypting a directory using the cipher /e command, any files added to that directory will also be automatically encrypted. Here is an example output:

Encrypting directory C:\path\to\file_or_directory

C:\path\to\file_or_directory\example.txt [OK]

Encryption was successful.

Decrypt a file or directory

To decrypt a file or directory, you can use the following code:

cipher /d:path\to\file_or_directory

Motivation: Decrypting files or directories is necessary when you no longer need the encryption or want to grant access to other users. This command is useful for reverting the encryption process and making the files or directories accessible without encryption.

Explanation: The /d option is used to decrypt a file or directory. The path\to\file_or_directory argument specifies the file or directory you want to decrypt.

Example Output: After decrypting a file using the cipher /d command, the file will no longer be encrypted. Here is an example output:

Decrypting directory C:\path\to\file_or_directory

C:\path\to\file_or_directory\example.txt [OK]

Decryption was successful.

Securely remove a file or directory

To securely remove a file or directory, you can use the following code:

cipher /w:path\to\file_or_directory

Motivation: Securely removing sensitive files or directories is essential to protect sensitive information from being recovered by unauthorized individuals. This command is useful when you want to permanently delete files or directories while ensuring they cannot be easily recovered.

Explanation: The /w option is used to securely remove a file or directory. The path\to\file_or_directory argument specifies the file or directory you want to remove securely.

Example Output: After securely removing a file or directory using the cipher /w command, the file or directory will be overwritten with random data, making it nearly impossible to recover. Here is an example output:

Wiping C:\path\to\file_or_directory\example.txt [OK]
Wiping C:\path\to\file_or_directory\subdirectory [OK]

1 file(s) or directory(ies) wiped.

Conclusion

In this article, we have explored the different use cases of the cipher command in Windows. We have provided code examples for displaying information about encrypted files or directories, encrypting and decrypting files or directories, and securely removing files or directories. By understanding and utilizing these different use cases, you can effectively manage file and directory encryption on NTFS volumes and protect sensitive information from unauthorized access.