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pythonsshsftpparamiko

"OverflowError: mode out of range" in Python when working with file mode/attributes returned by Paramiko

I am trying to make a SFTP script to go through a directory and get all the files in it, inside this directory there are subdirectories that I would like to exclude. However when I use the stat.S_ISREG function it gives an error of

OverflowError: mode out of range

From what I have read it seems like an error that Paramiko has with the handling of the bits that the server returns. Is there a way to solve this error, or some other way to differentiate files from folders based on the st_mode? I was thinking of validating if the st_mode is greater than 34000 exclude it and take it as a folder but I don't know if it is correct.

The code is the following:

client_ssh = paramiko.SSHClient()
client_ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
client_ssh.connect(host,username=user,password=pwd)
sftp_client = client_ssh.open_sftp()
df_file_info_sftp = pd.DataFrame([attr.__dict__ for attr in sftp_client.listdir_attr(directorio_remoto)]).sort_values("st_mtime", ascending=False)
for row in df_file_info_sftp.itertuples():
    print (row.filename)
    if stat.S_ISDIR(row.st_mode):
        print('Carpeta:')
    if stat.S_ISREG(row.st_mode):
        print('Archivo:' + row.filename)
sftp_client.close
client_ssh.close

The error is: enter image description here

From what I have read, it seems to be an error that Paramiko has with the handling of the bits returned by the server (apparently there are more than 16 and that is why the error)

Solution

  • There's no error in Paramiko. It's just that Paramiko (or actually your server) can return more permissons bits than Python stat module can handle.

    I've explained this in:
    Pysftp "cd" fails against AIX server with "OverflowError: mode out of range" error

    If you work with such server, you either have to analyze the bits without using the stat functions, like:

    S_IFMT = 0o170000
(row.st_mode & S_IFMT) == stat.S_IFDIR

    Or trim the excess bites, before passing the value to stat functions:

    stat.S_ISDIR(row.st_mode & 0xFFFF)

    Obligatory warning: Do not use AutoAddPolicy this way – You are losing a protection against MITM attacks by doing so. For a correct solution, see Paramiko "Unknown Server".