SFTPServer Class

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The SFTPServer class is used to create a Secure File Transfer Protocol (SFTP) server.

Syntax

class ipworkssftp.SFTPServer

Remarks

The SFTPServer class provides a simple way to create a Secure File Transfer Protocol (SFTP) server. Any SFTP client will be able to connect and transfer files to and from the server.

Getting Started

To begin, first provide a valid certificate with a private key in the ssh_cert property.

Optionally set the root_directory property to a valid local path. If this property is set, the class will serve files from this location, and when clients connect, they will see this as their initial directory. If this property is not set, then the class will fire events allowing customized responses for each operation.

To start the server, set listening to True.

Client Authentication

Client authentication is handled through the on_ssh_user_auth_request event. Inside this event, the Accept parameter determines whether authentication is accepted; this parameter should be set to True if a successful authentication is detected and False otherwise.

When a client connects, the AuthMethod parameter indicates the method of authentication the client wishes to use. Connecting clients will initially attempt authentication with an AuthMethod of "none". This is done with the expectation that the request will fail and the server will provide a list of support authentication methods. The client then selects an available method and reauthenticates. If AuthMethod is "none", Accept should be set to False.

For password authentication, the User parameter will hold the client's username and the AuthParam parameter will hold the password provided by the client. An external list of known usernames and passwords should be maintained to check these values against.

For publickey authentication, the User parameter will hold the client's username and the AuthParam parameter will hold the key provided by the client. This key should be compared to an external list of known keys and usernames.

For keyboard-interactive authentication, the on_ssh_user_auth_request event will fire multiple times; once for each prompt and response sent by the client. The index of the response is specified as a suffix in the AuthMethod parameter (e.g., keyboard-interactive-1, keyboard-interactive-2), and AuthParam will contain the client's response to the prompt. Finally, on_ssh_user_auth_request will fire one last time with AuthMethod set to "keyboard-interactive" and AuthParam set to an empty string. The Accept parameter must be set to True each time the event fires for the authentication process to succeed.

Directory Listing

When a client requests a directory listing, the on_dir_list event fires with the Path parameter set to the directory to enumerate. If the directory listing is allowed, the appropriate set of files should be passed to the set_file_list method. The StatusCode parameter should be set according to the status of the operation, and the valid status codes can be found in the documentation for the on_dir_list event.

Handling Events

Event handlers are the primary method of customizing the class's functionality. When a client attempts to connect, open a file, authenticate to the server, and so on, the corresponding SFTPServer event will fire to allow for custom handling of the client's request.

The following events are fired both before and after the requested operation is executed:

• on_dir_create
• on_dir_list
• on_dir_remove
• on_file_open
• on_file_remove
• on_file_rename
• on_file_write
• on_set_attributes

Each of these events has a BeforeExec event parameter that is True when the event is fired before execution of the operation, and False after execution of the operation. Handling the event before execution provides an opportunity to use custom logic to determine whether the operation should be denied, diverted, or otherwise modified. Handling the event after execution provides an opportunity to report success or any errors related to the operation to the client.

The following events are fired only after the requested operation is executed:

• on_file_close
• on_file_read
• on_get_attributes
• on_resolve_path

Any logic to deny opening a file for read or write should be done in the on_file_open event handler.

Note: Server components are designed to process events as they occur. To ensure that events are processed in a timely manner, do_events should be called in a loop after the server is started.

Property List

The following is the full list of the properties of the class with short descriptions. Click on the links for further details.

Method List

The following is the full list of the methods of the class with short descriptions. Click on the links for further details.

Event List

The following is the full list of the events fired by the class with short descriptions. Click on the links for further details.

Config Settings

The following is a list of config settings for the class with short descriptions. Click on the links for further details.

connection_backlog Property

This property includes the maximum number of pending connections maintained by the Transmission Control Protocol (TCP)/IP subsystem.

Syntax

def get_connection_backlog() -> int: ...
def set_connection_backlog(value: int) -> None: ...

connection_backlog = property(get_connection_backlog, set_connection_backlog)

Default Value

5

Remarks

This property contains the maximum number of pending connections maintained by the TCP/IP subsystem. This value reflects the SOMAXCONN option for the main listening socket. The default value for most systems is 5. You may set this property to a larger value if the server is expected to receive a large number of connections, and queuing them is desirable.

sftp_connection_count Property

The number of records in the SFTPConnection arrays.

Syntax

def get_sftp_connection_count() -> int: ...

sftp_connection_count = property(get_sftp_connection_count, None)

Default Value

0

Remarks

This property controls the size of the following arrays:

• sftp_connection_connected
• sftp_connection_error_message
• sftp_connection_file_data
• sftp_connection_local_address
• sftp_connection_protocol_version
• sftp_connection_remote_host
• sftp_connection_remote_port
• sftp_connection_timeout

The array indices start at 0 and end at sftp_connection_count - 1.

This property is read-only.

sftp_connection_connected Property

This property indicates the status of individual connections.

Syntax

def get_sftp_connection_connected(connection_id: int) -> bool: ...

Default Value

FALSE

Remarks

This property indicates the status of individual connections.

When True, the connection is established. Use the disconnect method to disconnect an existing connection.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

This property is read-only.

sftp_connection_error_message Property

ErrorMessage is used together with status codes returned from events to send informative errors back to the secure file transfer protocol (SFTP) client through the SSH_FXP_STATUS message.

Syntax

def get_sftp_connection_error_message(connection_id: int) -> str: ...

Default Value

""

Remarks

sftp_connection_error_message is used together with status codes returned from events to send informative errors back to the secure file transfer protocol (SFTP) client through the SSH_FXP_STATUS message. If left blank, the class will set a default message based on the returned status code.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

This property is read-only.

sftp_connection_file_data Property

The FileData should be set or read when processing read/write file events.

Syntax

def get_sftp_connection_file_data(connection_id: int) -> bytes: ...
def set_sftp_connection_file_data(connection_id: int, value: bytes) -> None: ...

Default Value

""

Remarks

The sftp_connection_file_data should be set or read when processing read/write file events.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

sftp_connection_local_address Property

This property shows the IP address of the interface through which the connection is passing.

Syntax

def get_sftp_connection_local_address(connection_id: int) -> str: ...

Default Value

""

Remarks

This property shows the IP address of the interface through which the connection is passing.

sftp_connection_local_address is important for multihomed hosts in cases in which it can be used to identify the particular network interface an individual connection is going through.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

This property is read-only.

sftp_connection_protocol_version Property

The ProtocolVersion shows the secure file transfer protocol (SFTP) protocol version negotiated with the client when the SFTP connection was established.

Syntax

def get_sftp_connection_protocol_version(connection_id: int) -> int: ...

Default Value

3

Remarks

The sftp_connection_protocol_version shows the secure file transfer protocol (SFTP) protocol version negotiated with the client when the SFTP connection was established.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

This property is read-only.

sftp_connection_remote_host Property

The RemoteHost shows the IP address of the remote host through which the connection is coming.

Syntax

def get_sftp_connection_remote_host(connection_id: int) -> str: ...

Default Value

""

Remarks

The sftp_connection_remote_host shows the IP address of the remote host through which the connection is coming.

The connection must be valid or an error will be fired.

If the class is configured to use a SOCKS firewall, the value assigned to this property may be preceded with an "*". If this is the case, the host name is passed to the firewall unresolved and the firewall performs the DNS resolution.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

This property is read-only.

sftp_connection_remote_port Property

The RemotePort shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming.

Syntax

def get_sftp_connection_remote_port(connection_id: int) -> int: ...

Default Value

0

Remarks

The sftp_connection_remote_port shows the Transmission Control Protocol (TCP) port on the remote host through which the connection is coming.

The connection must be valid or an error will be fired.

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

This property is read-only.

sftp_connection_timeout Property

This property contains a timeout for the class.

Syntax

def get_sftp_connection_timeout(connection_id: int) -> int: ...
def set_sftp_connection_timeout(connection_id: int, value: int) -> None: ...

Default Value

0

Remarks

This property contains a timeout for the class.

If the timeout property is set to 0, all operations return immediately, potentially failing with an 'WOULDBLOCK' error if data cannot be sent or received immediately.

If timeout is set to a positive value, the class will automatically retry each operation that otherwise would result in a 'WOULDBLOCK' error for a maximum of timeout seconds.

The class will use do_events to enter an efficient wait loop during any potential waiting period, making sure that all system events are processed immediately as they arrive. This ensures that the host application does not freeze and remains responsive.

If timeout expires, and the operation is not yet complete, the class fails with an error.

Note: By default, all timeouts are inactivity timeouts, that is, the timeout period is extended by timeout seconds when any amount of data is successfully sent or received.

The default value for the timeout property is 0 (asynchronous operation).

The connection_id parameter specifies the index of the item in the array. The size of the array is controlled by the sftp_connection_count property.

default_auth_methods Property

The supported authentication methods.

Syntax

def get_default_auth_methods() -> str: ...
def set_default_auth_methods(value: str) -> None: ...

default_auth_methods = property(get_default_auth_methods, set_default_auth_methods)

Default Value

"password,publickey"

Remarks

This property specifies the supported authentication methods. The client will choose one of the supported mechanisms when authenticating to the class.

This must be a comma-separated list of values. For more information on authenticating clients, see the on_ssh_user_auth_request event.

The following is a list of methods implemented by the class:

default_timeout Property

An initial timeout value to be used by incoming connections.

Syntax

def get_default_timeout() -> int: ...
def set_default_timeout(value: int) -> None: ...

default_timeout = property(get_default_timeout, set_default_timeout)

Default Value

60

Remarks

This property is used by the class to set the operational timeout value of all inbound connections once they are established. If the timeout is set to 0, all inbound connections will behave asynchronously. The default value is 60, meaning the class will behave synchronously.

keyboard_interactive_message Property

The instructions to send to the client during keyboard-interactive authentication.

Syntax

def get_keyboard_interactive_message() -> str: ...
def set_keyboard_interactive_message(value: str) -> None: ...

keyboard_interactive_message = property(get_keyboard_interactive_message, set_keyboard_interactive_message)

Default Value

""

Remarks

This property should be set to the main instructions to send to the client during keyboard-interactive authentication.

keyboard_interactive_prompt_count Property

The number of records in the KeyboardInteractivePrompt arrays.

Syntax

def get_keyboard_interactive_prompt_count() -> int: ...
def set_keyboard_interactive_prompt_count(value: int) -> None: ...

keyboard_interactive_prompt_count = property(get_keyboard_interactive_prompt_count, set_keyboard_interactive_prompt_count)

Default Value

0

Remarks

This property controls the size of the following arrays:

• keyboard_interactive_prompt_echo
• keyboard_interactive_prompt_prompt

The array indices start at 0 and end at keyboard_interactive_prompt_count - 1.

keyboard_interactive_prompt_echo Property

This property specifies whether or not the client should echo the value entered by the user.

Syntax

def get_keyboard_interactive_prompt_echo(prompt_index: int) -> bool: ...
def set_keyboard_interactive_prompt_echo(prompt_index: int, value: bool) -> None: ...

Default Value

FALSE

Remarks

This property specifies whether or not the client should echo the value entered by the user.

The prompt_index parameter specifies the index of the item in the array. The size of the array is controlled by the keyboard_interactive_prompt_count property.

keyboard_interactive_prompt_prompt Property

This property contains the prompt label or text the client should present to the user.

Syntax

def get_keyboard_interactive_prompt_prompt(prompt_index: int) -> str: ...
def set_keyboard_interactive_prompt_prompt(prompt_index: int, value: str) -> None: ...

Default Value

""

Remarks

This property contains the prompt label or text the client should present to the user.

The prompt_index parameter specifies the index of the item in the array. The size of the array is controlled by the keyboard_interactive_prompt_count property.

listening Property

This property indicates whether the class is listening for incoming connections on LocalPort.

Syntax

def get_listening() -> bool: ...

listening = property(get_listening, None)

Default Value

FALSE

Remarks

This property indicates whether the class is listening for connections on the port specified by the local_port property. Use the start_listening and stop_listening methods to control whether the class is listening.

This property is read-only.

local_host Property

The name of the local host or user-assigned IP interface through which connections are initiated or accepted.

Syntax

def get_local_host() -> str: ...
def set_local_host(value: str) -> None: ...

local_host = property(get_local_host, set_local_host)

Default Value

""

Remarks

This property contains the name of the local host as obtained by the gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multihomed hosts (machines with more than one IP interface) setting LocalHost to the IP address of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface. It is recommended to provide an IP address rather than a hostname when setting this property to ensure the desired interface is used.

If the class is connected, the local_host property shows the IP address of the interface through which the connection is made in internet dotted format (aaa.bbb.ccc.ddd). In most cases, this is the address of the local host, except for multihomed hosts (machines with more than one IP interface).

Note: local_host is not persistent. You must always set it in code, and never in the property window.

local_port Property

The Transmission Control Protocol (TCP) port in the local host where the class listens.

Syntax

def get_local_port() -> int: ...
def set_local_port(value: int) -> None: ...

local_port = property(get_local_port, set_local_port)

Default Value

22

Remarks

The local_port property must be set before TCPServer starts listening. If its value is 0, then the TCP/IP subsystem picks a port number at random. The port number can be found by checking the value of the local_port property after TCPServer is in listening mode (after successfully assigning True to the listening property).

The service port is not shared among servers (i.e., only one TCPServer can be 'listening' on a particular port at one time).

root_directory Property

The root directory for the entire secure file transfer protocol (SFTP) server.

Syntax

def get_root_directory() -> str: ...
def set_root_directory(value: str) -> None: ...

root_directory = property(get_root_directory, set_root_directory)

Default Value

""

Remarks

root_directory specifies the root of the SFTP server ('/'). If a value is provided, the class will handle all requests by doing all file operations itself, but the events will still give you the opportunity to override the default values and operations, as necessary.

If a value is not provided, all events must be handled appropriately to ensure correct operation.

ssh_cert_effective_date Property

The date on which this certificate becomes valid.

Syntax

def get_ssh_cert_effective_date() -> str: ...

ssh_cert_effective_date = property(get_ssh_cert_effective_date, None)

Default Value

""

Remarks

The date on which this certificate becomes valid. Before this date, it is not valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2000 15:00:00.

This property is read-only.

ssh_cert_expiration_date Property

The date on which the certificate expires.

Syntax

def get_ssh_cert_expiration_date() -> str: ...

ssh_cert_expiration_date = property(get_ssh_cert_expiration_date, None)

Default Value

""

Remarks

The date on which the certificate expires. After this date, the certificate will no longer be valid. The date is localized to the system's time zone. The following example illustrates the format of an encoded date:

23-Jan-2001 15:00:00.

This property is read-only.

ssh_cert_extended_key_usage Property

A comma-delimited list of extended key usage identifiers.

Syntax

def get_ssh_cert_extended_key_usage() -> str: ...

ssh_cert_extended_key_usage = property(get_ssh_cert_extended_key_usage, None)

Default Value

""

Remarks

A comma-delimited list of extended key usage identifiers. These are the same as ASN.1 object identifiers (OIDs).

This property is read-only.

ssh_cert_fingerprint Property

The hex-encoded, 16-byte MD5 fingerprint of the certificate.

Syntax

def get_ssh_cert_fingerprint() -> str: ...

ssh_cert_fingerprint = property(get_ssh_cert_fingerprint, None)

Default Value

""

Remarks

The hex-encoded, 16-byte MD5 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: bc:2a:72:af:fe:58:17:43:7a:5f:ba:5a:7c:90:f7:02

This property is read-only.

ssh_cert_fingerprint_sha1 Property

The hex-encoded, 20-byte SHA-1 fingerprint of the certificate.

Syntax

def get_ssh_cert_fingerprint_sha1() -> str: ...

ssh_cert_fingerprint_sha1 = property(get_ssh_cert_fingerprint_sha1, None)

Default Value

""

Remarks

The hex-encoded, 20-byte SHA-1 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 30:7b:fa:38:65:83:ff:da:b4:4e:07:3f:17:b8:a4:ed:80:be:ff:84

This property is read-only.

ssh_cert_fingerprint_sha256 Property

The hex-encoded, 32-byte SHA-256 fingerprint of the certificate.

Syntax

def get_ssh_cert_fingerprint_sha256() -> str: ...

ssh_cert_fingerprint_sha256 = property(get_ssh_cert_fingerprint_sha256, None)

Default Value

""

Remarks

The hex-encoded, 32-byte SHA-256 fingerprint of the certificate. This property is primarily used for keys which do not have a corresponding X.509 public certificate, such as PEM keys that only contain a private key. It is commonly used for SSH keys.

The following example illustrates the format: 6a:80:5c:33:a9:43:ea:b0:96:12:8a:64:96:30:ef:4a:8a:96:86:ce:f4:c7:be:10:24:8e:2b:60:9e:f3:59:53

This property is read-only.

ssh_cert_issuer Property

The issuer of the certificate.

Syntax

def get_ssh_cert_issuer() -> str: ...

ssh_cert_issuer = property(get_ssh_cert_issuer, None)

Default Value

""

Remarks

The issuer of the certificate. This property contains a string representation of the name of the issuing authority for the certificate.

This property is read-only.

ssh_cert_private_key Property

The private key of the certificate (if available).

Syntax

def get_ssh_cert_private_key() -> str: ...

ssh_cert_private_key = property(get_ssh_cert_private_key, None)

Default Value

""

Remarks

The private key of the certificate (if available). The key is provided as PEM/Base64-encoded data.

Note: The ssh_cert_private_key may be available but not exportable. In this case, ssh_cert_private_key returns an empty string.

This property is read-only.

ssh_cert_private_key_available Property

Whether a PrivateKey is available for the selected certificate.

Syntax

def get_ssh_cert_private_key_available() -> bool: ...

ssh_cert_private_key_available = property(get_ssh_cert_private_key_available, None)

Default Value

FALSE

Remarks

Whether a ssh_cert_private_key is available for the selected certificate. If ssh_cert_private_key_available is True, the certificate may be used for authentication purposes (e.g., server authentication).

This property is read-only.

ssh_cert_private_key_container Property

The name of the PrivateKey container for the certificate (if available).

Syntax

def get_ssh_cert_private_key_container() -> str: ...

ssh_cert_private_key_container = property(get_ssh_cert_private_key_container, None)

Default Value

""

Remarks

The name of the ssh_cert_private_key container for the certificate (if available). This functionality is available only on Windows platforms.

This property is read-only.

ssh_cert_public_key Property

The public key of the certificate.

Syntax

def get_ssh_cert_public_key() -> str: ...

ssh_cert_public_key = property(get_ssh_cert_public_key, None)

Default Value

""

Remarks

The public key of the certificate. The key is provided as PEM/Base64-encoded data.

This property is read-only.

ssh_cert_public_key_algorithm Property

The textual description of the certificate's public key algorithm.

Syntax

def get_ssh_cert_public_key_algorithm() -> str: ...

ssh_cert_public_key_algorithm = property(get_ssh_cert_public_key_algorithm, None)

Default Value

""

Remarks

The textual description of the certificate's public key algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_DH") or an object identifier (OID) string representing the algorithm.

This property is read-only.

ssh_cert_public_key_length Property

The length of the certificate's public key (in bits).

Syntax

def get_ssh_cert_public_key_length() -> int: ...

ssh_cert_public_key_length = property(get_ssh_cert_public_key_length, None)

Default Value

0

Remarks

The length of the certificate's public key (in bits). Common values are 512, 1024, and 2048.

This property is read-only.

ssh_cert_serial_number Property

The serial number of the certificate encoded as a string.

Syntax

def get_ssh_cert_serial_number() -> str: ...

ssh_cert_serial_number = property(get_ssh_cert_serial_number, None)

Default Value

""

Remarks

The serial number of the certificate encoded as a string. The number is encoded as a series of hexadecimal digits, with each pair representing a byte of the serial number.

This property is read-only.

ssh_cert_signature_algorithm Property

The text description of the certificate's signature algorithm.

Syntax

def get_ssh_cert_signature_algorithm() -> str: ...

ssh_cert_signature_algorithm = property(get_ssh_cert_signature_algorithm, None)

Default Value

""

Remarks

The text description of the certificate's signature algorithm. The property contains either the name of the algorithm (e.g., "RSA" or "RSA_MD5RSA") or an object identifier (OID) string representing the algorithm.

This property is read-only.

ssh_cert_store Property

The name of the certificate store for the client certificate.

Syntax

def get_ssh_cert_store() -> bytes: ...
def set_ssh_cert_store(value: bytes) -> None: ...

ssh_cert_store = property(get_ssh_cert_store, set_ssh_cert_store)

Default Value

"MY"

Remarks

The name of the certificate store for the client certificate.

The ssh_cert_store_type property denotes the type of the certificate store specified by ssh_cert_store. If the store is password-protected, specify the password in ssh_cert_store_password.

ssh_cert_store is used in conjunction with the ssh_cert_subject property to specify client certificates. If ssh_cert_store has a value, and ssh_cert_subject or ssh_cert_encoded is set, a search for a certificate is initiated. Please see the ssh_cert_subject property for details.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

ssh_cert_store_password Property

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

Syntax

def get_ssh_cert_store_password() -> str: ...
def set_ssh_cert_store_password(value: str) -> None: ...

ssh_cert_store_password = property(get_ssh_cert_store_password, set_ssh_cert_store_password)

Default Value

""

Remarks

If the type of certificate store requires a password, this property is used to specify the password needed to open the certificate store.

ssh_cert_store_type Property

The type of certificate store for this certificate.

Syntax

def get_ssh_cert_store_type() -> int: ...
def set_ssh_cert_store_type(value: int) -> None: ...

ssh_cert_store_type = property(get_ssh_cert_store_type, set_ssh_cert_store_type)

Default Value

0

Remarks

The type of certificate store for this certificate.

The class supports both public and private keys in a variety of formats. When the cstAuto value is used, the class will automatically determine the type. This property can take one of the following values:

ssh_cert_subject_alt_names Property

Comma-separated lists of alternative subject names for the certificate.

Syntax

def get_ssh_cert_subject_alt_names() -> str: ...

ssh_cert_subject_alt_names = property(get_ssh_cert_subject_alt_names, None)

Default Value

""

Remarks

Comma-separated lists of alternative subject names for the certificate.

This property is read-only.

ssh_cert_thumbprint_md5 Property

The MD5 hash of the certificate.

Syntax

def get_ssh_cert_thumbprint_md5() -> str: ...

ssh_cert_thumbprint_md5 = property(get_ssh_cert_thumbprint_md5, None)

Default Value

""

Remarks

The MD5 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

This property is read-only.

ssh_cert_thumbprint_sha1 Property

The SHA-1 hash of the certificate.

Syntax

def get_ssh_cert_thumbprint_sha1() -> str: ...

ssh_cert_thumbprint_sha1 = property(get_ssh_cert_thumbprint_sha1, None)

Default Value

""

Remarks

The SHA-1 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

This property is read-only.

ssh_cert_thumbprint_sha256 Property

The SHA-256 hash of the certificate.

Syntax

def get_ssh_cert_thumbprint_sha256() -> str: ...

ssh_cert_thumbprint_sha256 = property(get_ssh_cert_thumbprint_sha256, None)

Default Value

""

Remarks

The SHA-256 hash of the certificate. It is primarily used for X.509 certificates. If the hash does not already exist, it is automatically computed.

This property is read-only.

ssh_cert_usage Property

The text description of UsageFlags .

Syntax

def get_ssh_cert_usage() -> str: ...

ssh_cert_usage = property(get_ssh_cert_usage, None)

Default Value

""

Remarks

The text description of ssh_cert_usage_flags.

This value will be one or more of the following strings and will be separated by commas:

• Digital Signature
• Non-Repudiation
• Key Encipherment
• Data Encipherment
• Key Agreement
• Certificate Signing
• CRL Signing
• Encipher Only

If the provider is OpenSSL, the value is a comma-separated list of X.509 certificate extension names.

This property is read-only.

ssh_cert_usage_flags Property

The flags that show intended use for the certificate.

Syntax

def get_ssh_cert_usage_flags() -> int: ...

ssh_cert_usage_flags = property(get_ssh_cert_usage_flags, None)

Default Value

0

Remarks

The flags that show intended use for the certificate. The value of ssh_cert_usage_flags is a combination of the following flags:

Please see the ssh_cert_usage property for a text representation of ssh_cert_usage_flags.

This functionality currently is not available when the provider is OpenSSL.

This property is read-only.

ssh_cert_version Property

The certificate's version number.

Syntax

def get_ssh_cert_version() -> str: ...

ssh_cert_version = property(get_ssh_cert_version, None)

Default Value

""

Remarks

The certificate's version number. The possible values are the strings "V1", "V2", and "V3".

This property is read-only.

ssh_cert_subject Property

The subject of the certificate used for client authentication.

Syntax

def get_ssh_cert_subject() -> str: ...
def set_ssh_cert_subject(value: str) -> None: ...

ssh_cert_subject = property(get_ssh_cert_subject, set_ssh_cert_subject)

Default Value

""

Remarks

The subject of the certificate used for client authentication.

This property must be set after all other certificate properties are set. When this property is set, a search is performed in the current certificate store to locate a certificate with a matching subject.

If a matching certificate is found, the property is set to the full subject of the matching certificate.

If an exact match is not found, the store is searched for subjects containing the value of the property.

If a match is still not found, the property is set to an empty string, and no certificate is selected.

The special value "*" picks a random certificate in the certificate store.

The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:

If a field value contains a comma, it must be quoted.

ssh_cert_encoded Property

The certificate (PEM/Base64 encoded).

Syntax

def get_ssh_cert_encoded() -> bytes: ...
def set_ssh_cert_encoded(value: bytes) -> None: ...

ssh_cert_encoded = property(get_ssh_cert_encoded, set_ssh_cert_encoded)

Default Value

""

Remarks

The certificate (PEM/Base64 encoded). This property is used to assign a specific certificate. The ssh_cert_store and ssh_cert_subject properties also may be used to specify a certificate.

When ssh_cert_encoded is set, a search is initiated in the current ssh_cert_store for the private key of the certificate. If the key is found, ssh_cert_subject is updated to reflect the full subject of the selected certificate; otherwise, ssh_cert_subject is set to an empty string.

ssh_compression_algorithms Property

The comma-separated list containing all allowable compression algorithms.

Syntax

def get_ssh_compression_algorithms() -> str: ...
def set_ssh_compression_algorithms(value: str) -> None: ...

ssh_compression_algorithms = property(get_ssh_compression_algorithms, set_ssh_compression_algorithms)

Default Value

"none,zlib"

Remarks

During the Secure Shell (SSH) handshake, this list will be used to negotiate the compression algorithm to be used between the client and server. This list is used for both directions: client to server and server to client. When negotiating algorithms, each side sends a list of all algorithms it supports or allows. The algorithm chosen for each direction is the first algorithm to appear in the sender's list that the receiver supports. Therefore, it is important to list multiple algorithms in preferential order. If no algorithm can be agreed on, the class will raise an error and the connection will be aborted.

At least one supported algorithm must appear in this list. The following compression algorithms are supported by the class:

• zlib
• zlib@openssh.com
• none

ssh_encryption_algorithms Property

The comma-separated list containing all allowable encryption algorithms.

Syntax

def get_ssh_encryption_algorithms() -> str: ...
def set_ssh_encryption_algorithms(value: str) -> None: ...

ssh_encryption_algorithms = property(get_ssh_encryption_algorithms, set_ssh_encryption_algorithms)

Default Value

"aes256-ctr,aes192-ctr,aes128-ctr,3des-ctr,arcfour256,arcfour128,arcfour,aes256-gcm@openssh.com,aes128-gcm@openssh.com,chacha20-poly1305@openssh.com"

Remarks

During the Secure Shell (SSH) handshake, this list will be used to negotiate the encryption algorithm to be used between the client and server. This list is used for both directions: client to server and server to client. When negotiating algorithms, each side sends a list of all algorithms it supports or allows. The algorithm chosen for each direction is the first algorithm to appear in the sender's list that the receiver supports. Therefore, it is important to list multiple algorithms in preferential order. If no algorithm can be agreed on, the class will raise an error and the connection will be aborted.

At least one supported algorithm must appear in this list. The following encryption algorithms are supported by the class:

config Method

Sets or retrieves a configuration setting.

Syntax

def config(configuration_string: str) -> str: ...

Remarks

config is a generic method available in every class. It is used to set and retrieve configuration settings for the class.

These settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the class, access to these internal properties is provided through the config method.

To set a configuration setting named PROPERTY, you must call Config("PROPERTY=VALUE"), where VALUE is the value of the setting expressed as a string. For boolean values, use the strings "True", "False", "0", "1", "Yes", or "No" (case does not matter).

To read (query) the value of a configuration setting, you must call Config("PROPERTY"). The value will be returned as a string.

disconnect Method

This method disconnects the specified client.

Syntax

def disconnect(connection_id: int) -> None: ...

Remarks

Calling this method will disconnect the client specified by the ConnectionId parameter.

do_events Method

This method processes events from the internal message queue.

Syntax

def do_events() -> None: ...

Remarks

When do_events is called, the class processes any available events. If no events are available, it waits for a preset period of time, and then returns.

exchange_keys Method

Causes the class to exchange a new set of session keys on the specified connection.

Syntax

def exchange_keys(connection_id: int) -> None: ...

Remarks

Secure Shell (SSH) key renegotiation can be initiated by either end of an established SSH connection. exchange_keys allows the server to start such a renegotiation with the client. During this process, on_ssh_status events will fire containing updates regarding the key negotiation process.

The SSH 2.0 specification recommends that key renegotiation be done once for 2 gigabytes (GB) of data processed by the connection, or once every day. This makes it more difficult to break the security of data-intensive or long-lived connections.

reset Method

This method will reset the class.

Syntax

def reset() -> None: ...

Remarks

This method will reset the class's properties to their default values.

set_file_list Method

Sets the file list for a connection during a directory listing request.

Syntax

def set_file_list(connection_id: int, list: ) -> None: ...

Remarks

set_file_list should be set when a directory listing is requested by the client. The list parameter should be a string of all the filenames to include, separated by CRLF.

shutdown Method

This method shuts down the server.

Syntax

def shutdown() -> None: ...

Remarks

This method shuts down the server. Calling this method is equivalent to calling stop_listening and then breaking every client connection by calling disconnect.

start_listening Method

This method starts listening for incoming connections.

Syntax

def start_listening() -> None: ...

Remarks

This method begins listening for incoming connections on the port specified by local_port. Once listening, events will fire as new clients connect and data are transferred.

To stop listening for new connections, call stop_listening. To stop listening for new connections and to disconnect all existing clients, call shutdown.

stop_listening Method

This method stops listening for new connections.

Syntax

def stop_listening() -> None: ...

Remarks

This method stops listening for new connections. After being called, any new connection attempts will be rejected. Calling this method does not disconnect existing connections.

To stop listening and to disconnect all existing clients, call shutdown instead.

on_connected Event

Fired immediately after a connection completes (or fails).

Syntax

class SFTPServerConnectedEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def status_code() -> int: ...

  @property
  def description() -> str: ...

  @property
  def cert_store_type() -> int: ...
  @cert_store_type.setter
  def cert_store_type(value) -> None: ...

  @property
  def cert_store() -> str: ...
  @cert_store.setter
  def cert_store(value) -> None: ...

  @property
  def cert_password() -> str: ...
  @cert_password.setter
  def cert_password(value) -> None: ...

  @property
  def cert_subject() -> str: ...
  @cert_subject.setter
  def cert_subject(value) -> None: ...

# In class SFTPServer:
@property
def on_connected() -> Callable[[SFTPServerConnectedEventParams], None]: ...
@on_connected.setter
def on_connected(event_hook: Callable[[SFTPServerConnectedEventParams], None]) -> None: ...

Remarks

If the connection is made normally, StatusCode is 0, and Description is "OK".

If the connection fails, StatusCode has the error code returned by the system. Description contains a description of this code. The value of StatusCode is equal to the value of the system error.

Please refer to the Error Codes section for more information.

ConnectionId is the connection Id of the client requesting the connection.

CertStoreType is the store type of the alternate certificate to use for this connection. The class supports both public and private keys in a variety of formats. When the cstAuto value is used, the class will automatically determine the type. This property can take one of the following values:

CertStore is the store name or location of the alternate certificate to use for this connection.

Designations of certificate stores are platform dependent.

The following designations are the most common User and Machine certificate stores in Windows:

When the certificate store type is cstPFXFile, this property must be set to the name of the file. When the type is cstPFXBlob, the property must be set to the binary contents of a PFX file (i.e., PKCS#12 certificate store).

CertPassword is the password of the certificate store containing the alternate certificate to use for this connection.

CertSubject is the subject of the alternate certificate to use for this connection.

The special value * matches any subject and will select the first certificate in the store. The certificate subject is a comma-separated list of distinguished name fields and values. For instance, "CN=www.server.com, OU=test, C=US, E=support@nsoftware.com". Common fields and their meanings are as follows:

If a field value contains a comma, it must be quoted.

on_connection_request Event

This event is fired when a request for connection comes from a remote host.

Syntax

class SFTPServerConnectionRequestEventParams(object):
  @property
  def address() -> str: ...

  @property
  def port() -> int: ...

  @property
  def accept() -> bool: ...
  @accept.setter
  def accept(value) -> None: ...

# In class SFTPServer:
@property
def on_connection_request() -> Callable[[SFTPServerConnectionRequestEventParams], None]: ...
@on_connection_request.setter
def on_connection_request(event_hook: Callable[[SFTPServerConnectionRequestEventParams], None]) -> None: ...

Remarks

This event indicates an incoming connection. The connection is accepted by default. Address and Port will contain information about the remote host requesting the inbound connection. If you want to refuse it, you can set the Accept parameter to False.

on_dir_create Event

Fired when a client wants to create a new directory.

Syntax

class SFTPServerDirCreateEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def file_type() -> int: ...

  @property
  def file_size() -> int: ...

  @property
  def file_owner() -> str: ...

  @property
  def file_group() -> str: ...

  @property
  def file_permissions() -> int: ...

  @property
  def file_a_time() -> int: ...

  @property
  def file_create_time() -> int: ...

  @property
  def file_m_time() -> int: ...

  @property
  def file_attrib_bits() -> int: ...

  @property
  def file_attrib_bits_valid() -> int: ...

  @property
  def other_attributes() -> str: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_dir_create() -> Callable[[SFTPServerDirCreateEventParams], None]: ...
@on_dir_create.setter
def on_dir_create(event_hook: Callable[[SFTPServerDirCreateEventParams], None]) -> None: ...

Remarks

The Path parameter specifies the path and name of the new directory.

This event is fired both before and after the directory is created. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

File/Directory Attributes are specified using the following values:

FileType: The type of file. Can be one of the following values:

• SSH_FILEXFER_TYPE_REGULAR (1)
• SSH_FILEXFER_TYPE_DIRECTORY (2)
• SSH_FILEXFER_TYPE_SYMLINK (3)
• SSH_FILEXFER_TYPE_SPECIAL (4)
• SSH_FILEXFER_TYPE_UNKNOWN (5)
• SSH_FILEXFER_TYPE_SOCKET (6)
• SSH_FILEXFER_TYPE_CHAR_DEVICE (7)
• SSH_FILEXFER_TYPE_BLOCK_DEVICE (8)
• SSH_FILEXFER_TYPE_FIFO (9)

FileSize: The file size, in bytes.

FileOwner: The file owner. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like user identifier. V4, V5, and V6 of the secure file transfer protocol (SFTP) allow for an arbitrary string.

FileGroup: The file owner group. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like group identifier. V4, V5, and V6 of the SFTP allow for an arbitrary string.

FilePermissions: The POSIX-style file permissions.

FileATime: The file last-access time, in milliseconds since January 1, 1970, in UTC.

FileCreateTime: The file creation time, in milliseconds since January 1, 1970, in UTC.

FileMTime: The file last-modified time, in milliseconds since January 1, 1970, in UTC.

FileAttrBits: The file attributes, as a combination of the following values:

• SSH_FILEXFER_ATTR_FLAGS_READONLY (0x00000001)
• SSH_FILEXFER_ATTR_FLAGS_SYSTEM (0x00000002)
• SSH_FILEXFER_ATTR_FLAGS_HIDDEN (0x00000004)
• SSH_FILEXFER_ATTR_FLAGS_CASE_INSENSITIVE (0x00000008)
• SSH_FILEXFER_ATTR_FLAGS_ARCHIVE (0x00000010)
• SSH_FILEXFER_ATTR_FLAGS_ENCRYPTED (0x00000020)
• SSH_FILEXFER_ATTR_FLAGS_COMPRESSED (0x00000040)
• SSH_FILEXFER_ATTR_FLAGS_SPARSE (0x00000080)
• SSH_FILEXFER_ATTR_FLAGS_APPEND_ONLY (0x00000100)
• SSH_FILEXFER_ATTR_FLAGS_IMMUTABLE (0x00000200)
• SSH_FILEXFER_ATTR_FLAGS_SYNC (0x00000400)
• SSH_FILEXFER_ATTR_FLAGS_TRANSLATION_ERR (0x00000800)

FileAttrBitsValid: A mask specifying which bits in FileAttrBits are supported by the server.

OtherAttributes: A semicolon (;) delimited list of Name=Value pairs of other attributes supported by SFTP. These include the following:

• MIMEType (String)
• AllocationSize (64-bit int)
• ATimeNS (int): ATime nanoseconds
• CreateTimeNS (int): CreateTime nanoseconds
• MTimeNS (int): MTime nanoseconds
• TextHint (8-bit int)
• LinkCount (int)
• UntranslatedName (String)

FileMimeType: The MIME type of the file.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_dir_list Event

Fired when a client attempts to open a directory for listing.

Syntax

class SFTPServerDirListEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_dir_list() -> Callable[[SFTPServerDirListEventParams], None]: ...
@on_dir_list.setter
def on_dir_list(event_hook: Callable[[SFTPServerDirListEventParams], None]) -> None: ...

Remarks

The on_dir_list event is fired when a secure file transfer protocol (SFTP) client sends an SSH_FXP_OPENDIR request. The Path parameter will contain the path of the directory to list.

When necessary, you should call set_file_list with the list of files and directories in Path.

This event is fired both before and after the directory is listed. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_dir_remove Event

Fired when a client wants to delete a directory.

Syntax

class SFTPServerDirRemoveEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_dir_remove() -> Callable[[SFTPServerDirRemoveEventParams], None]: ...
@on_dir_remove.setter
def on_dir_remove(event_hook: Callable[[SFTPServerDirRemoveEventParams], None]) -> None: ...

Remarks

The Path parameter will specify the directory to delete.

This event is fired both before and after the directory is deleted. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_disconnected Event

This event is fired when a connection is closed.

Syntax

class SFTPServerDisconnectedEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def status_code() -> int: ...

  @property
  def description() -> str: ...

# In class SFTPServer:
@property
def on_disconnected() -> Callable[[SFTPServerDisconnectedEventParams], None]: ...
@on_disconnected.setter
def on_disconnected(event_hook: Callable[[SFTPServerDisconnectedEventParams], None]) -> None: ...

Remarks

If the connection is broken normally, StatusCode is 0, and Description is "OK".

If the connection is broken for any other reason, StatusCode has the error code returned by the system. Description contains a description of this code. The value of StatusCode is equal to the value of the system error.

Please refer to the Error Codes section for more information.

on_error Event

Fired when errors occur during data delivery.

Syntax

class SFTPServerErrorEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def error_code() -> int: ...

  @property
  def description() -> str: ...

# In class SFTPServer:
@property
def on_error() -> Callable[[SFTPServerErrorEventParams], None]: ...
@on_error.setter
def on_error(event_hook: Callable[[SFTPServerErrorEventParams], None]) -> None: ...

Remarks

The on_error event is fired in case of exceptional conditions during message processing. Normally the class fails with an error.

ConnectionId contains an error code and Description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

ErrorCode contains an error code and Description contains a textual description of the error. For a list of valid error codes and their descriptions, please refer to the Error Codes section.

on_file_close Event

Fired when a client attempts to close an open file or directory handle.

Syntax

class SFTPServerFileCloseEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def handle() -> str: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_file_close() -> Callable[[SFTPServerFileCloseEventParams], None]: ...
@on_file_close.setter
def on_file_close(event_hook: Callable[[SFTPServerFileCloseEventParams], None]) -> None: ...

Remarks

The on_file_close event is fired when a secure file transfer protocol (SFTP) client sends an SSH_FXP_CLOSE request. The Path parameter will contain the path of the file to close.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_file_open Event

Fired when a client wants to open or create a file.

Syntax

class SFTPServerFileOpenEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def desired_access() -> int: ...

  @property
  def flags() -> int: ...

  @property
  def file_type() -> int: ...

  @property
  def file_size() -> int: ...

  @property
  def file_owner() -> str: ...

  @property
  def file_group() -> str: ...

  @property
  def file_permissions() -> int: ...

  @property
  def file_a_time() -> int: ...

  @property
  def file_create_time() -> int: ...

  @property
  def file_m_time() -> int: ...

  @property
  def file_attrib_bits() -> int: ...

  @property
  def file_attrib_bits_valid() -> int: ...

  @property
  def other_attributes() -> str: ...

  @property
  def handle() -> str: ...
  @handle.setter
  def handle(value) -> None: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_file_open() -> Callable[[SFTPServerFileOpenEventParams], None]: ...
@on_file_open.setter
def on_file_open(event_hook: Callable[[SFTPServerFileOpenEventParams], None]) -> None: ...

Remarks

The Path parameter specifies the path and name of the file to open, create. If the operation can be completed successfully, the Handle parameter should be set to the handle identifying the opened file.

Note: The Handle parameter is limited to a 256-byte string. By default, the class will provide an incremental numeric string value for the Handle.

This event is fired both before and after the file is opened. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

The Flags parameter specifies file creation and locking options as a bitmask. This may be a combination of the following values:

• SSH_FXF_READ (0x00000001)
• SSH_FXF_WRITE (0x00000002)
• SSH_FXF_APPEND (0x00000004)
• SSH_FXF_CREAT (0x00000008)
• SSH_FXF_TRUNC (0x00000010)
• SSH_FXF_EXCL (0x00000020)

The DesiredAccess parameter is a bitmask containing a combination of values from the ace-mask flags (only for protocol versions 4 and up). This may be a combination of the following values:

• ACE4_READ_DATA (0x00000001)
• ACE4_LIST_DIRECTORY (0x00000001)
• ACE4_WRITE_DATA (0x00000002)
• ACE4_ADD_FILE (0x00000002)
• ACE4_APPEND_DATA (0x00000004)
• ACE4_ADD_SUBDIRECTORY (0x00000004)
• ACE4_READ_NAMED_ATTRS (0x00000008)
• ACE4_WRITE_NAMED_ATTRS (0x00000010)
• ACE4_EXECUTE (0x00000020)
• ACE4_DELETE_CHILD (0x00000040)
• ACE4_READ_ATTRIBUTES (0x00000080)
• ACE4_WRITE_ATTRIBUTES (0x00000100)
• ACE4_DELETE (0x00010000)
• ACE4_READ_ACL (0x00020000)
• ACE4_WRITE_ACL (0x00040000)
• ACE4_WRITE_OWNER (0x00080000)
• ACE4_SYNCHRONIZE (0x00100000)

File/Directory Attributes are specified using the following values:

FileType: The type of file. Can be one of the following values:

• SSH_FILEXFER_TYPE_REGULAR (1)
• SSH_FILEXFER_TYPE_DIRECTORY (2)
• SSH_FILEXFER_TYPE_SYMLINK (3)
• SSH_FILEXFER_TYPE_SPECIAL (4)
• SSH_FILEXFER_TYPE_UNKNOWN (5)
• SSH_FILEXFER_TYPE_SOCKET (6)
• SSH_FILEXFER_TYPE_CHAR_DEVICE (7)
• SSH_FILEXFER_TYPE_BLOCK_DEVICE (8)
• SSH_FILEXFER_TYPE_FIFO (9)

FileSize: The file size, in bytes.

FileOwner: The file owner. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like user identifier. V4, V5, and V6 of the secure file transfer protocol (SFTP) allow for an arbitrary string.

FileGroup: The file owner group. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like group identifier. V4, V5, and V6 of the SFTP allow for an arbitrary string.

FilePermissions: The POSIX-style file permissions.

FileATime: The file last-access time, in milliseconds since January 1, 1970, in UTC.

FileCreateTime: The file creation time, in milliseconds since January 1, 1970, in UTC.

FileMTime: The file last-modified time, in milliseconds since January 1, 1970, in UTC.

FileAttrBits: The file attributes, as a combination of the following values:

• SSH_FILEXFER_ATTR_FLAGS_READONLY (0x00000001)
• SSH_FILEXFER_ATTR_FLAGS_SYSTEM (0x00000002)
• SSH_FILEXFER_ATTR_FLAGS_HIDDEN (0x00000004)
• SSH_FILEXFER_ATTR_FLAGS_CASE_INSENSITIVE (0x00000008)
• SSH_FILEXFER_ATTR_FLAGS_ARCHIVE (0x00000010)
• SSH_FILEXFER_ATTR_FLAGS_ENCRYPTED (0x00000020)
• SSH_FILEXFER_ATTR_FLAGS_COMPRESSED (0x00000040)
• SSH_FILEXFER_ATTR_FLAGS_SPARSE (0x00000080)
• SSH_FILEXFER_ATTR_FLAGS_APPEND_ONLY (0x00000100)
• SSH_FILEXFER_ATTR_FLAGS_IMMUTABLE (0x00000200)
• SSH_FILEXFER_ATTR_FLAGS_SYNC (0x00000400)
• SSH_FILEXFER_ATTR_FLAGS_TRANSLATION_ERR (0x00000800)

FileAttrBitsValid: A mask specifying which bits in FileAttrBits are supported by the server.

OtherAttributes: A semicolon (;) delimited list of Name=Value pairs of other attributes supported by SFTP. These include the following:

• MIMEType (String)
• AllocationSize (64-bit int)
• ATimeNS (int): ATime nanoseconds
• CreateTimeNS (int): CreateTime nanoseconds
• MTimeNS (int): MTime nanoseconds
• TextHint (8-bit int)
• LinkCount (int)
• UntranslatedName (String)

FileMimeType: The MIME type of the file.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_file_read Event

Fired when a client wants to read from an open file.

Syntax

class SFTPServerFileReadEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def handle() -> str: ...

  @property
  def file_offset() -> int: ...

  @property
  def length() -> int: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_file_read() -> Callable[[SFTPServerFileReadEventParams], None]: ...
@on_file_read.setter
def on_file_read(event_hook: Callable[[SFTPServerFileReadEventParams], None]) -> None: ...

Remarks

The Handle parameter identifies an open file on the server. FileOffset specifies the position from which to read data. Length specifies how much data to read. The data read should be set to through sftp_connection_file_data

When processing a read request, the server should attempt to read at most Length bytes, but it is okay to read less than Length bytes as well, if no more data are available.

When there are no more data to be read from the file, set StatusCode to SSH_FXS_EOF.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_file_remove Event

Fired when a client wants to delete a file.

Syntax

class SFTPServerFileRemoveEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_file_remove() -> Callable[[SFTPServerFileRemoveEventParams], None]: ...
@on_file_remove.setter
def on_file_remove(event_hook: Callable[[SFTPServerFileRemoveEventParams], None]) -> None: ...

Remarks

The Path parameter will specify the file to delete.

This event is fired both before and after the file is removed. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_file_rename Event

Fired when a client wants to rename a file.

Syntax

class SFTPServerFileRenameEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def new_path() -> str: ...

  @property
  def flags() -> int: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_file_rename() -> Callable[[SFTPServerFileRenameEventParams], None]: ...
@on_file_rename.setter
def on_file_rename(event_hook: Callable[[SFTPServerFileRenameEventParams], None]) -> None: ...

Remarks

The Path parameter will specify the file to rename and NewPath will specify the new name. The Flags parameter will be a bit mask of the values SSH_FXF_RENAME_OVERWRITE (0x00000001), SSH_FXF_RENAME_ATOMIC (0x00000002), and SSH_FXF_RENAME_NATIVE (0x00000004).

This event is fired both before and after the file is renamed. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_file_write Event

Fired when a client wants to write to an open file.

Syntax

class SFTPServerFileWriteEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def handle() -> str: ...

  @property
  def file_offset() -> int: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_file_write() -> Callable[[SFTPServerFileWriteEventParams], None]: ...
@on_file_write.setter
def on_file_write(event_hook: Callable[[SFTPServerFileWriteEventParams], None]) -> None: ...

Remarks

The Handle parameter identifies an open file on the server. FileOffset specifies the position at which to write data. The data to write can be retrieved through sftp_connection_file_data

This event is fired both before and after the file is written. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_get_attributes Event

Fired when a client needs to get file information.

Syntax

class SFTPServerGetAttributesEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def flags() -> int: ...

  @property
  def file_type() -> int: ...
  @file_type.setter
  def file_type(value) -> None: ...

  @property
  def file_size() -> int: ...
  @file_size.setter
  def file_size(value) -> None: ...

  @property
  def file_owner() -> str: ...
  @file_owner.setter
  def file_owner(value) -> None: ...

  @property
  def file_group() -> str: ...
  @file_group.setter
  def file_group(value) -> None: ...

  @property
  def file_permissions() -> int: ...
  @file_permissions.setter
  def file_permissions(value) -> None: ...

  @property
  def file_a_time() -> int: ...
  @file_a_time.setter
  def file_a_time(value) -> None: ...

  @property
  def file_create_time() -> int: ...
  @file_create_time.setter
  def file_create_time(value) -> None: ...

  @property
  def file_m_time() -> int: ...
  @file_m_time.setter
  def file_m_time(value) -> None: ...

  @property
  def file_attrib_bits() -> int: ...
  @file_attrib_bits.setter
  def file_attrib_bits(value) -> None: ...

  @property
  def file_attrib_bits_valid() -> int: ...
  @file_attrib_bits_valid.setter
  def file_attrib_bits_valid(value) -> None: ...

  @property
  def other_attributes() -> str: ...
  @other_attributes.setter
  def other_attributes(value) -> None: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_get_attributes() -> Callable[[SFTPServerGetAttributesEventParams], None]: ...
@on_get_attributes.setter
def on_get_attributes(event_hook: Callable[[SFTPServerGetAttributesEventParams], None]) -> None: ...

Remarks

The on_get_attributes event fires when a secure file transfer protocol (SFTP) client sends an SSH_FXP_STAT, SSH_FXP_LSTAT, or SSH_FXP_FSTAT request. Path is the file path. Flags specifies the set of file attributes the client is interested in.

File/Directory Attributes are specified using the following values:

FileType: The type of file. Can be one of the following values:

• SSH_FILEXFER_TYPE_REGULAR (1)
• SSH_FILEXFER_TYPE_DIRECTORY (2)
• SSH_FILEXFER_TYPE_SYMLINK (3)
• SSH_FILEXFER_TYPE_SPECIAL (4)
• SSH_FILEXFER_TYPE_UNKNOWN (5)
• SSH_FILEXFER_TYPE_SOCKET (6)
• SSH_FILEXFER_TYPE_CHAR_DEVICE (7)
• SSH_FILEXFER_TYPE_BLOCK_DEVICE (8)
• SSH_FILEXFER_TYPE_FIFO (9)

FileSize: The file size, in bytes.

FileOwner: The file owner. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like user identifier. V4, V5, and V6 of the secure file transfer protocol (SFTP) allow for an arbitrary string.

FileGroup: The file owner group. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like group identifier. V4, V5, and V6 of the SFTP allow for an arbitrary string.

FilePermissions: The POSIX-style file permissions.

FileATime: The file last-access time, in milliseconds since January 1, 1970, in UTC.

FileCreateTime: The file creation time, in milliseconds since January 1, 1970, in UTC.

FileMTime: The file last-modified time, in milliseconds since January 1, 1970, in UTC.

FileAttrBits: The file attributes, as a combination of the following values:

• SSH_FILEXFER_ATTR_FLAGS_READONLY (0x00000001)
• SSH_FILEXFER_ATTR_FLAGS_SYSTEM (0x00000002)
• SSH_FILEXFER_ATTR_FLAGS_HIDDEN (0x00000004)
• SSH_FILEXFER_ATTR_FLAGS_CASE_INSENSITIVE (0x00000008)
• SSH_FILEXFER_ATTR_FLAGS_ARCHIVE (0x00000010)
• SSH_FILEXFER_ATTR_FLAGS_ENCRYPTED (0x00000020)
• SSH_FILEXFER_ATTR_FLAGS_COMPRESSED (0x00000040)
• SSH_FILEXFER_ATTR_FLAGS_SPARSE (0x00000080)
• SSH_FILEXFER_ATTR_FLAGS_APPEND_ONLY (0x00000100)
• SSH_FILEXFER_ATTR_FLAGS_IMMUTABLE (0x00000200)
• SSH_FILEXFER_ATTR_FLAGS_SYNC (0x00000400)
• SSH_FILEXFER_ATTR_FLAGS_TRANSLATION_ERR (0x00000800)

FileAttrBitsValid: A mask specifying which bits in FileAttrBits are supported by the server.

OtherAttributes: A semicolon (;) delimited list of Name=Value pairs of other attributes supported by SFTP. These include the following:

• MIMEType (String)
• AllocationSize (64-bit int)
• ATimeNS (int): ATime nanoseconds
• CreateTimeNS (int): CreateTime nanoseconds
• MTimeNS (int): MTime nanoseconds
• TextHint (8-bit int)
• LinkCount (int)
• UntranslatedName (String)

FileMimeType: The MIME type of the file.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_log Event

Fired once for each log message.

Syntax

class SFTPServerLogEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def log_level() -> int: ...

  @property
  def message() -> str: ...

  @property
  def log_type() -> str: ...

# In class SFTPServer:
@property
def on_log() -> Callable[[SFTPServerLogEventParams], None]: ...
@on_log.setter
def on_log(event_hook: Callable[[SFTPServerLogEventParams], None]) -> None: ...

Remarks

Fired once for each log message generated by the class. The verbosity is controlled by the LogLevel setting.

LogLevel indicates the detail level of the message. Possible values are as follows:

Message is the log message.

LogType is reserved for future use.

ConnectionId identifies the connection to which the log message applies.

on_resolve_path Event

Fired when a client attempts to canonicalize a path.

Syntax

class SFTPServerResolvePathEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def original_path() -> str: ...

  @property
  def control_flags() -> int: ...

  @property
  def real_path() -> str: ...
  @real_path.setter
  def real_path(value) -> None: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_resolve_path() -> Callable[[SFTPServerResolvePathEventParams], None]: ...
@on_resolve_path.setter
def on_resolve_path(event_hook: Callable[[SFTPServerResolvePathEventParams], None]) -> None: ...

Remarks

The on_resolve_path event is fired when a secure file transfer protocol (SFTP) client sends an SSH_FXP_REALPATH request. The OriginalPath parameter will contain the path the client wants to canonicalize. ControlFlags can have one of the following values:

RealPath should be set to the resulting canonicalized path, and StatusCode should be set to indicate the success or failure of the operation to the client.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_set_attributes Event

Fired when a client attempts to set file or directory attributes.

Syntax

class SFTPServerSetAttributesEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def path() -> str: ...

  @property
  def file_type() -> int: ...

  @property
  def file_size() -> int: ...

  @property
  def file_owner() -> str: ...

  @property
  def file_group() -> str: ...

  @property
  def file_permissions() -> int: ...

  @property
  def file_a_time() -> int: ...

  @property
  def file_create_time() -> int: ...

  @property
  def file_m_time() -> int: ...

  @property
  def file_attrib_bits() -> int: ...

  @property
  def file_attrib_bits_valid() -> int: ...

  @property
  def other_attributes() -> str: ...

  @property
  def before_exec() -> bool: ...

  @property
  def status_code() -> int: ...
  @status_code.setter
  def status_code(value) -> None: ...

# In class SFTPServer:
@property
def on_set_attributes() -> Callable[[SFTPServerSetAttributesEventParams], None]: ...
@on_set_attributes.setter
def on_set_attributes(event_hook: Callable[[SFTPServerSetAttributesEventParams], None]) -> None: ...

Remarks

The on_set_attributes event is fired when a secure file transfer protocol (SFTP) client sends an SSH_FXP_SETSTAT, SSH_FXP_FSETSTAT, or SSH_FXP_FSTAT request. Path is the path of the file or directory the client wants to set attributes for.

This event is fired both before and after the attributes are set. The BeforeExec parameter is True before the operation has been executed and False otherwise. Handling this event before execution of the operation provides an opportunity to add custom logic that may prevent or deny the operation. Handling this event after execution of the operation provides an opportunity to report any errors that may have occurred during the operation.

File/Directory Attributes are specified using the following values:

FileType: The type of file. Can be one of the following values:

• SSH_FILEXFER_TYPE_REGULAR (1)
• SSH_FILEXFER_TYPE_DIRECTORY (2)
• SSH_FILEXFER_TYPE_SYMLINK (3)
• SSH_FILEXFER_TYPE_SPECIAL (4)
• SSH_FILEXFER_TYPE_UNKNOWN (5)
• SSH_FILEXFER_TYPE_SOCKET (6)
• SSH_FILEXFER_TYPE_CHAR_DEVICE (7)
• SSH_FILEXFER_TYPE_BLOCK_DEVICE (8)
• SSH_FILEXFER_TYPE_FIFO (9)

FileSize: The file size, in bytes.

FileOwner: The file owner. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like user identifier. V4, V5, and V6 of the secure file transfer protocol (SFTP) allow for an arbitrary string.

FileGroup: The file owner group. If the ProtocolVersion configuration option is "3" (default), this field should be a numeric Unix-like group identifier. V4, V5, and V6 of the SFTP allow for an arbitrary string.

FilePermissions: The POSIX-style file permissions.

FileATime: The file last-access time, in milliseconds since January 1, 1970, in UTC.

FileCreateTime: The file creation time, in milliseconds since January 1, 1970, in UTC.

FileMTime: The file last-modified time, in milliseconds since January 1, 1970, in UTC.

FileAttrBits: The file attributes, as a combination of the following values:

• SSH_FILEXFER_ATTR_FLAGS_READONLY (0x00000001)
• SSH_FILEXFER_ATTR_FLAGS_SYSTEM (0x00000002)
• SSH_FILEXFER_ATTR_FLAGS_HIDDEN (0x00000004)
• SSH_FILEXFER_ATTR_FLAGS_CASE_INSENSITIVE (0x00000008)
• SSH_FILEXFER_ATTR_FLAGS_ARCHIVE (0x00000010)
• SSH_FILEXFER_ATTR_FLAGS_ENCRYPTED (0x00000020)
• SSH_FILEXFER_ATTR_FLAGS_COMPRESSED (0x00000040)
• SSH_FILEXFER_ATTR_FLAGS_SPARSE (0x00000080)
• SSH_FILEXFER_ATTR_FLAGS_APPEND_ONLY (0x00000100)
• SSH_FILEXFER_ATTR_FLAGS_IMMUTABLE (0x00000200)
• SSH_FILEXFER_ATTR_FLAGS_SYNC (0x00000400)
• SSH_FILEXFER_ATTR_FLAGS_TRANSLATION_ERR (0x00000800)

FileAttrBitsValid: A mask specifying which bits in FileAttrBits are supported by the server.

OtherAttributes: A semicolon (;) delimited list of Name=Value pairs of other attributes supported by SFTP. These include the following:

• MIMEType (String)
• AllocationSize (64-bit int)
• ATimeNS (int): ATime nanoseconds
• CreateTimeNS (int): CreateTime nanoseconds
• MTimeNS (int): MTime nanoseconds
• TextHint (8-bit int)
• LinkCount (int)
• UntranslatedName (String)

FileMimeType: The MIME type of the file.

Valid status codes are as follows:

• SSH_FX_OK 0
• SSH_FX_EOF 1
• SSH_FX_NO_SUCH_FILE 2
• SSH_FX_PERMISSION_DENIED 3
• SSH_FX_FAILURE 4
• SSH_FX_BAD_MESSAGE 5
• SSH_FX_NO_CONNECTION 6
• SSH_FX_CONNECTION_LOST 7
• SSH_FX_OP_UNSUPPORTED 8
• SSH_FX_INVALID_HANDLE 9
• SSH_FX_NO_SUCH_PATH 10
• SSH_FX_FILE_ALREADY_EXISTS 11
• SSH_FX_WRITE_PROTECT 12
• SSH_FX_NO_MEDIA 13
• SSH_FX_NO_SPACE_ON_FILESYSTEM 14
• SSH_FX_QUOTA_EXCEEDED 15
• SSH_FX_UNKNOWN_PRINCIPAL 16
• SSH_FX_LOCK_CONFLICT 17
• SSH_FX_DIR_NOT_EMPTY 18
• SSH_FX_NOT_A_DIRECTORY 19
• SSH_FX_INVALID_FILENAME 20
• SSH_FX_LINK_LOOP 21
• SSH_FX_CANNOT_DELETE 22
• SSH_FX_INVALID_PARAMETER 23
• SSH_FX_FILE_IS_A_DIRECTORY 24
• SSH_FX_BYTE_RANGE_LOCK_CONFLICT 25
• SSH_FX_BYTE_RANGE_LOCK_REFUSED 26
• SSH_FX_DELETE_PENDING 27
• SSH_FX_FILE_CORRUPT 28
• SSH_FX_OWNER_INVALID 29
• SSH_FX_GROUP_INVALID 30
• SSH_FX_NO_MATCHING_BYTE_RANGE_LOCK 31

on_ssh_status Event

Fired to track the progress of the secure connection.

Syntax

class SFTPServerSSHStatusEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def message() -> str: ...

# In class SFTPServer:
@property
def on_ssh_status() -> Callable[[SFTPServerSSHStatusEventParams], None]: ...
@on_ssh_status.setter
def on_ssh_status(event_hook: Callable[[SFTPServerSSHStatusEventParams], None]) -> None: ...

Remarks

This event is fired for informational and logging purposes only and is used to track the progress of the connection.

on_ssh_user_auth_request Event

Fired when a client attempts to authenticate a connection.

Syntax

class SFTPServerSSHUserAuthRequestEventParams(object):
  @property
  def connection_id() -> int: ...

  @property
  def user() -> str: ...

  @property
  def service() -> str: ...

  @property
  def auth_method() -> str: ...

  @property
  def auth_param() -> str: ...

  @property
  def accept() -> bool: ...
  @accept.setter
  def accept(value) -> None: ...

  @property
  def partial_success() -> bool: ...
  @partial_success.setter
  def partial_success(value) -> None: ...

  @property
  def available_methods() -> str: ...
  @available_methods.setter
  def available_methods(value) -> None: ...

  @property
  def home_dir() -> str: ...
  @home_dir.setter
  def home_dir(value) -> None: ...

  @property
  def key_algorithm() -> str: ...

# In class SFTPServer:
@property
def on_ssh_user_auth_request() -> Callable[[SFTPServerSSHUserAuthRequestEventParams], None]: ...
@on_ssh_user_auth_request.setter
def on_ssh_user_auth_request(event_hook: Callable[[SFTPServerSSHUserAuthRequestEventParams], None]) -> None: ...

Remarks

The on_ssh_user_auth_request event fires when a Secure Shell (SSH) client attempts to authenticate itself on a particular connection. ConnectionId will identify the connection being authenticated. User will be the name of the account requesting authentication, and Service will contain the name of the service the client is wishing to access.

AuthMethod will denote which method the client is attempting to use to authenticate itself. AuthParam will contain the value of the authentication token used by the client. If the token is acceptable, you may set Accept to True to allow the SFTPServer to authenticate the client. If it is not, set Accept to False.

Connecting clients will initially attempt authentication with an AuthMethod of "none". This is done with the expectation that the request will fail and the server will send a list of supported methods back to the client. In your implementation, check the AuthMethod parameter; if it is "none", you should set AvailableMethods and reject the request. The client will select one of the available methods and reauthenticate.

You may set AvailableMethods to a comma-delimited string of authentication methods that are available for the user. This list will be sent back to the client so that it may perform further authentication attempts.

The following is a list of methods implemented by the class:

If the user authentication succeeds, you may set HomeDir to the virtual path representing the initial directory for the user. If not set, the initial directory will be root_directory.

The PartialSuccess parameter is used only when multifactor authentication is needed. To implement multifactor authentication when this event fires, first verify the AuthParam for the given AuthMethod. If accepted, set PartialSuccess to True and Accept to False. The client should then send the authentication request for a different form of authentication specified in AvailableMethods. You may continue to set PartialSuccess to True until all authentication requirements are satisfied. Once all requirements are satisfied set Accept to True.

KeyAlgorithm holds the signing algorithm used when the client attempts public key authentication. Possible values are as follows:

• ssh-rsa
• rsa-sha2-256
• rsa-sha2-512
• ssh-dss
• ecdsa-sha2-nistp256
• ecdsa-sha2-nistp384
• ecdsa-sha2-nistp521
• x509v3-sign-rsa
• x509v3-sign-dss

Note: Processing long-running requests, including sending channel data, inside this event may cause the underlying transport to stop processing Secure Shell (SSH) data until the event returns. To prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

SFTPServer Config Settings

SFTPServer Config Settings

Root Directory: /

bin
boot
etc
home
  user1
    testfolder

Home Directory: /home/user1

/testfolder

Root Directory: /

bin
boot
etc
home
  user1
    testfolder

Home Directory: /

/testfolder

SSHServer Config Settings

*SSH-1.99-*,*SSH-2.0-*,*SSH-2.99-*

TCPServer Config Settings

Base Config Settings

SFTPServer Errors

SFTPServer Errors

The class may also return one of the following error codes, which are inherited from other classes.

SSHServer Errors

TCPServer Errors

TCP/IP Errors