SFTPServer Class

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The SFTPServer class is used to create a SFTP Server.

Syntax

ipworksssh.Sftpserver

Remarks

The SFTPServer class provides a simple way to create a 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 private key in the SSHCert property.

Optionally set the RootDirectory 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 SSHUserAuthRequest 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 re-authenticates. 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 and external list of known keys and usernames.

For keyboard-interactive authentication, the SSHUserAuthRequest 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, etc), and AuthParam will contain the client's response to the prompt. Finally, SSHUserAuthRequest 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 in order for the authentication process to succeed.

Directory Listing

When a client requests a directory listing, the DirList 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 SetFileList 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 DirList 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, etc, 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:

• DirCreate
• DirList
• DirRemove
• FileOpen
• FileRemove
• FileRename
• FileWrite
• SetAttributes

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:

• FileClose
• FileRead
• GetAttributes
• ResolvePath

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

Note: Server components are designed to process events as they occur. To ensure that events are processed in a timely manner, DoEvents 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.

ConnectionBacklog Property (SFTPServer Class)

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

Syntax

public int getConnectionBacklog();


public void setConnectionBacklog(int connectionBacklog);

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.

This property is not available at design time.

Connections Property (SFTPServer Class)

A collection of currently connected SFTP clients.

Syntax

public SFTPConnectionMap getConnections();

Remarks

This property is a collection of currently connected clients. All of the connections may be managed using this property. Each connection is described by the different fields of the SFTPConnection type.

This property is read-only.

DefaultAuthMethods Property (SFTPServer Class)

Specifies the supported authentication methods.

Syntax

public String getDefaultAuthMethods();


public void setDefaultAuthMethods(String defaultAuthMethods);

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 SSHUserAuthRequest event.

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

DefaultTimeout Property (SFTPServer Class)

An initial timeout value to be used by incoming connections.

Syntax

public int getDefaultTimeout();


public void setDefaultTimeout(int defaultTimeout);

Default Value

60

Remarks

If the DefaultTimeout property is set to 0, all operations will run uninterrupted until successful completion or an error condition is encountered.

If DefaultTimeout is set to a positive value, the class will wait for the operation to complete before returning control.

The class will use DoEvents 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 throws an exception.

Please note that by default, all timeouts are inactivity timeouts, i.e. the timeout period is extended by Timeout seconds when any amount of data is successfully sent or received.

The default value for the DefaultTimeout property is 60 (seconds).

KeyboardInteractiveMessage Property (SFTPServer Class)

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

Syntax

public String getKeyboardInteractiveMessage();


public void setKeyboardInteractiveMessage(String keyboardInteractiveMessage);

Default Value

""

Remarks

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

KeyboardInteractivePrompts Property (SFTPServer Class)

A collection of prompts to present to the user for keyboard-interactive authentication.

Syntax

public SSHPromptList getKeyboardInteractivePrompts();


public void setKeyboardInteractivePrompts(SSHPromptList keyboardInteractivePrompts);

Remarks

This property is a collection of prompts to present to the user during keyboard-authentication. It is used together with the KeyboardInteractiveMessage property.

Listening Property (SFTPServer Class)

If set to True, the class accepts incoming connections on LocalPort.

Syntax

public boolean isListening();


public void setListening(boolean listening);

Default Value

False

Remarks

This property indicates whether the class is listening for connections on the port specified by the LocalPort property.

Note: Use the StartListening and StopListening methods to control whether the class is listening.

This property is not available at design time.

LocalHost Property (SFTPServer Class)

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

Syntax

public String getLocalHost();


public void setLocalHost(String localHost);

Default Value

""

Remarks

The LocalHost 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 multi-homed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the class initiate connections (or accept in the case of server classs) only through that interface.

If the class is connected, the LocalHost 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 multi-homed hosts (machines with more than one IP interface).

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

LocalPort Property (SFTPServer Class)

The TCP port in the local host where the class listens.

Syntax

public int getLocalPort();


public void setLocalPort(int localPort);

Default Value

22

Remarks

The LocalPort 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 LocalPort 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. there can be only one TCPServer 'listening' on a particular port at one time).

RootDirectory Property (SFTPServer Class)

The root directory for the entire SFTP server.

Syntax

public String getRootDirectory();


public void setRootDirectory(String rootDirectory);

Default Value

""

Remarks

RootDirectory 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/operations as necessary.

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

SSHCert Property (SFTPServer Class)

A certificate to be used during SSH negotiation.

Syntax

public Certificate getSSHCert();


public void setSSHCert(Certificate SSHCert);

Remarks

The digital certificate that the server will use during SSH negotiation. A certificate with a private key is required for session authentication and encryption.

This is the server's certificate, and must be set prior to setting Listening to True.

SSHCompressionAlgorithms Property (SFTPServer Class)

A comma-separated list containing all allowable compression algorithms.

Syntax

public String getSSHCompressionAlgorithms();


public void setSSHCompressionAlgorithms(String SSHCompressionAlgorithms);

Default Value

"none,zlib"

Remarks

During the 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, so it is important to list multiple algorithms in preferential order. If no algorithm can be agreed upon, 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

SSHEncryptionAlgorithms Property (SFTPServer Class)

A comma-separated list containing all allowable encryption algorithms.

Syntax

public String getSSHEncryptionAlgorithms();


public void setSSHEncryptionAlgorithms(String SSHEncryptionAlgorithms);

Default Value

"aes256-ctr,aes192-ctr,aes128-ctr,aes256-cbc,aes192-cbc,aes128-cbc,3des-ctr,3des-cbc,blowfish-cbc,arcfour256,arcfour128,arcfour,cast128-cbc,aes256-gcm@openssh.com,aes128-gcm@openssh.com,chacha20-poly1305@openssh.com"

Remarks

During the 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, so it is important to list multiple algorithms in preferential order. If no algorithm can be agreed upon, 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 (Sftpserver Class)

Sets or retrieves a configuration setting.

Syntax

public String config(String configurationString);

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 (Sftpserver Class)

This method disconnects the specified client.

Syntax

public void disconnect(String connectionId);

Remarks

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

DoEvents Method (Sftpserver Class)

Processes events from the internal message queue.

Syntax

public void doEvents();

Remarks

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

ExchangeKeys Method (Sftpserver Class)

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

Syntax

public void exchangeKeys(String connectionId);

Remarks

SSH key renegotiation can be initiated by either end of an established SSH connection. ExchangeKeys allows the server to start such a renegotiation with the client. During this process, SSHStatus 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 (Sftpserver Class)

Reset the class.

Syntax

public void reset();

Remarks

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

SetFileList Method (Sftpserver Class)

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

Syntax

public void setFileList(String connectionId, String[] list);

Remarks

SetFileList should be set when a directory listing is requested by the client.

Shutdown Method (Sftpserver Class)

This method shuts down the server.

Syntax

public void shutdown();

Remarks

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

StartListening Method (Sftpserver Class)

This method starts listening for incoming connections.

Syntax

public void startListening();

Remarks

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

To stop listening for new connections, call StopListening. To stop listening for new connections and to disconnect all existing clients, call Shutdown.

StopListening Method (Sftpserver Class)

This method stops listening for new connections.

Syntax

public void stopListening();

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.

Connected Event (Sftpserver Class)

This event is fired immediately after a connection completes (or fails).

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void connected(SftpserverConnectedEvent e) {}
  ...
}

public class SftpserverConnectedEvent {
  public String connectionId;
  public int statusCode;
  public String description;
  public int certStoreType;
  public String certStore;
  public String certPassword;
  public String certSubject;
}

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 field 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:

In Java, the certificate store normally is a file containing certificates and optional private keys.

When the certificate store type is PFXFile, this property must be set to the name of the file. When the type is PFXBlob, 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.

ConnectionRequest Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void connectionRequest(SftpserverConnectionRequestEvent e) {}
  ...
}

public class SftpserverConnectionRequestEvent {
  public String address;
  public int port;
  public boolean accept;
}

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.

DirCreate Event (Sftpserver Class)

Fires when a client wants to create a new directory.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void dirCreate(SftpserverDirCreateEvent e) {}
  ...
}

public class SftpserverDirCreateEvent {
  public String connectionId;
  public String user;
  public String path;
  public int fileType;
  public long fileSize;
  public String fileOwner;
  public String fileGroup;
  public int filePermissions;
  public long fileATime;
  public long fileCreateTime;
  public long fileMTime;
  public int fileAttribBits;
  public int fileAttribBitsValid;
  public String otherAttributes;
  public boolean beforeExec;
  public int statusCode;
}

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-V6 of the SFTP Protocol allow 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-V6 of the SFTP Protocol allow an arbitrary string.

FilePermissions: The POSIX-style file permissions.

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

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

FileMTime: The file last-modified time, in milliseconds since Jan 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 semi-colon (';') delimited list of Name=Value pairs of other attributes supported by SFTP. These include:

• 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:

• 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

DirList Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void dirList(SftpserverDirListEvent e) {}
  ...
}

public class SftpserverDirListEvent {
  public String connectionId;
  public String user;
  public String path;
  public boolean beforeExec;
  public int statusCode;
}

Remarks

The DirList event fires when an 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 SetFileList 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:

• 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

DirRemove Event (Sftpserver Class)

Fires when a client wants to delete a directory.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void dirRemove(SftpserverDirRemoveEvent e) {}
  ...
}

public class SftpserverDirRemoveEvent {
  public String connectionId;
  public String user;
  public String path;
  public boolean beforeExec;
  public int statusCode;
}

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:

• 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

Disconnected Event (Sftpserver Class)

This event is fired when a connection is closed.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void disconnected(SftpserverDisconnectedEvent e) {}
  ...
}

public class SftpserverDisconnectedEvent {
  public String connectionId;
  public int statusCode;
  public String description;
}

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.

Error Event (Sftpserver Class)

Information about errors during data delivery.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void error(SftpserverErrorEvent e) {}
  ...
}

public class SftpserverErrorEvent {
  public String connectionId;
  public int errorCode;
  public String description;
}

Remarks

The Error event is fired in case of exceptional conditions during message processing. Normally the class throws an exception.

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.

FileClose Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void fileClose(SftpserverFileCloseEvent e) {}
  ...
}

public class SftpserverFileCloseEvent {
  public String connectionId;
  public String user;
  public String path;
  public String handle;
  public int statusCode;
}

Remarks

The FileClose event fires when an SFTP client sends an SSH_FXP_CLOSE request. The Path parameter will contain the path of the file to close.

Valid status codes are:

• 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

FileOpen Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void fileOpen(SftpserverFileOpenEvent e) {}
  ...
}

public class SftpserverFileOpenEvent {
  public String connectionId;
  public String user;
  public String path;
  public int desiredAccess;
  public int flags;
  public int fileType;
  public long fileSize;
  public String fileOwner;
  public String fileGroup;
  public int filePermissions;
  public long fileATime;
  public long fileCreateTime;
  public long fileMTime;
  public int fileAttribBits;
  public int fileAttribBitsValid;
  public String otherAttributes;
  public String handle;
  public boolean beforeExec;
  public int statusCode;
}

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. Please note that 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-V6 of the SFTP Protocol allow 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-V6 of the SFTP Protocol allow an arbitrary string.

FilePermissions: The POSIX-style file permissions.

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

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

FileMTime: The file last-modified time, in milliseconds since Jan 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 semi-colon (';') delimited list of Name=Value pairs of other attributes supported by SFTP. These include:

• 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:

• 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

FileRead Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void fileRead(SftpserverFileReadEvent e) {}
  ...
}

public class SftpserverFileReadEvent {
  public String connectionId;
  public String user;
  public String handle;
  public long fileOffset;
  public int length;
  public int statusCode;
}

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 FileData

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

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

Valid status codes are:

• 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

FileRemove Event (Sftpserver Class)

Fires when a client wants to delete a file.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void fileRemove(SftpserverFileRemoveEvent e) {}
  ...
}

public class SftpserverFileRemoveEvent {
  public String connectionId;
  public String user;
  public String path;
  public boolean beforeExec;
  public int statusCode;
}

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:

• 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

FileRename Event (Sftpserver Class)

Fires when a client wants to rename a file.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void fileRename(SftpserverFileRenameEvent e) {}
  ...
}

public class SftpserverFileRenameEvent {
  public String connectionId;
  public String user;
  public String path;
  public String newPath;
  public int flags;
  public boolean beforeExec;
  public int statusCode;
}

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:

• 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

FileWrite Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void fileWrite(SftpserverFileWriteEvent e) {}
  ...
}

public class SftpserverFileWriteEvent {
  public String connectionId;
  public String user;
  public String handle;
  public long fileOffset;
  public boolean beforeExec;
  public int statusCode;
}

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 FileData

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:

• 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

GetAttributes Event (Sftpserver Class)

Fires when a client needs to get file information.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void getAttributes(SftpserverGetAttributesEvent e) {}
  ...
}

public class SftpserverGetAttributesEvent {
  public String connectionId;
  public String user;
  public String path;
  public int flags;
  public int fileType;
  public long fileSize;
  public String fileOwner;
  public String fileGroup;
  public int filePermissions;
  public long fileATime;
  public long fileCreateTime;
  public long fileMTime;
  public int fileAttribBits;
  public int fileAttribBitsValid;
  public String otherAttributes;
  public int statusCode;
}

Remarks

The GetAttributes event fires when an 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-V6 of the SFTP Protocol allow 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-V6 of the SFTP Protocol allow an arbitrary string.

FilePermissions: The POSIX-style file permissions.

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

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

FileMTime: The file last-modified time, in milliseconds since Jan 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 semi-colon (';') delimited list of Name=Value pairs of other attributes supported by SFTP. These include:

• 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:

• 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

Log Event (Sftpserver Class)

Fires once for each log message.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void log(SftpserverLogEvent e) {}
  ...
}

public class SftpserverLogEvent {
  public String connectionId;
  public int logLevel;
  public String message;
  public String logType;
}

Remarks

This event fires once for each log messages generated by the class. The verbosity is controlled by the LogLevel setting.

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

Message is the log message.

LogType is reserved for future use.

ConnectionId identifies the connection to which the log message applies.

ResolvePath Event (Sftpserver Class)

Fires when a client attempts to canonicalize a path.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void resolvePath(SftpserverResolvePathEvent e) {}
  ...
}

public class SftpserverResolvePathEvent {
  public String connectionId;
  public String user;
  public String originalPath;
  public int controlFlags;
  public String realPath;
  public int statusCode;
}

Remarks

The ResolvePath event fires when an 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 success or failure of the operation to the client.

Valid status codes are:

• 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

SetAttributes Event (Sftpserver Class)

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

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void setAttributes(SftpserverSetAttributesEvent e) {}
  ...
}

public class SftpserverSetAttributesEvent {
  public String connectionId;
  public String user;
  public String path;
  public int fileType;
  public long fileSize;
  public String fileOwner;
  public String fileGroup;
  public int filePermissions;
  public long fileATime;
  public long fileCreateTime;
  public long fileMTime;
  public int fileAttribBits;
  public int fileAttribBitsValid;
  public String otherAttributes;
  public boolean beforeExec;
  public int statusCode;
}

Remarks

The SetAttributes event fires when an 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-V6 of the SFTP Protocol allow 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-V6 of the SFTP Protocol allow an arbitrary string.

FilePermissions: The POSIX-style file permissions.

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

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

FileMTime: The file last-modified time, in milliseconds since Jan 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 semi-colon (';') delimited list of Name=Value pairs of other attributes supported by SFTP. These include:

• 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:

• 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

SSHStatus Event (Sftpserver Class)

Shows the progress of the secure connection.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void SSHStatus(SftpserverSSHStatusEvent e) {}
  ...
}

public class SftpserverSSHStatusEvent {
  public String connectionId;
  public String message;
}

Remarks

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

SSHUserAuthRequest Event (Sftpserver Class)

Fires when a client attempts to authenticate a connection.

Syntax

public class DefaultSftpserverEventListener implements SftpserverEventListener {
  ...
  public void SSHUserAuthRequest(SftpserverSSHUserAuthRequestEvent e) {}
  ...
}

public class SftpserverSSHUserAuthRequestEvent {
  public String connectionId;
  public String user;
  public String service;
  public String authMethod;
  public String authParam;
  public boolean accept;
  public boolean partialSuccess;
  public String availableMethods;
  public String homeDir;
  public String keyAlgorithm;
}

Remarks

The SSHUserAuthRequest event fires when an 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 re-authenticate.

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:

In the case 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 RootDirectory.

The PartialSuccess parameter is only used when multi-factor authentication is needed. To implement multi-factor 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 hold the signing algorithm used when the client attempts public key authentication. Possible values are:

• 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 SSH data until the event returns. In order to prevent this from happening, all requests should be processed asynchronously in a separate thread outside of this event.

Certificate Type

This is the digital certificate being used.

Remarks

This type describes the current digital certificate. The certificate may be a public or private key. The fields are used to identify or select certificates.

Fields

Constructors

public Certificate();

Creates a Certificate instance whose properties can be set. This is useful for use with CERTMGR when generating new certificates.

public Certificate( certificateFile);

Opens CertificateFile and reads out the contents as an X.509 public key.

public Certificate( certificateData);

Parses CertificateData as an X.509 public key.

public Certificate( certStoreType,  store,  storePassword,  subject);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  store,  storePassword,  subject,  configurationString);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. ConfigurationString is a newline separated list of name-value pairs that may be used to modify the default behavior. Possible values include "PersistPFXKey", which shows whether or not the PFX key is persisted after performing operations with the private key. This correlates to the PKCS12_NO_PERSIST_KEY CryptoAPI option. The default value is True (the key is persisted). "Thumbprint" - an MD5, SHA-1, or SHA-256 thumbprint of the certificate to load. When specified, this value is used to select the certificate in the store. This is applicable to cstUser, cstMachine, cstPublicKeyFile, and cstPFXFile store types. "UseInternalSecurityAPI" shows whether the platform (default) or the internal security API is used when performing certificate-related operations. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  store,  storePassword,  encoded);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a file containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

public Certificate( certStoreType,  storeBlob,  storePassword,  subject);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. StoreBlob is a string (binary- or Base64-encoded) containing the certificate data. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  storeBlob,  storePassword,  subject,  configurationString);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. StoreBlob is a string (binary- or Base64-encoded) containing the certificate data. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will attempt to find the certificate identified by Subject . This can be either a complete or a substring match of the X.509 certificate's subject Distinguished Name (DN).

public Certificate( certStoreType,  storeBlob,  storePassword,  encoded);

CertStoreType identifies the type of certificate store to use. See StoreType for descriptions of the different certificate stores. Store is a string (binary- or Base64-encoded) containing the certificate store. StorePassword is the password used to protect the store. After the store has been successfully opened, the class will load Encoded as an X.509 certificate and search the opened store for a corresponding private key.

SFTPConnection Type

A currently connected client.

Remarks

This type describes the connection of a client which is currently connected to the class. You may use the different fields of this type to manage the connection.

Fields

Constructors

public SFTPConnection();

SSHPrompt Type

A prompt to provide to the client during keyboard-interactive authentication.

Remarks

This type describes a prompt the SSH daemon will send to the client when requesting keyboard-interactive authentication.

Fields

Constructors

public SSHPrompt();

public SSHPrompt( prompt,  echo);

Config Settings (Sftpserver Class)

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

Trappable Errors (Sftpserver Class)

SFTPServer Errors

SSHServer Errors

TCPServer Errors

TCP/IP Errors