Ssh C# WinRT Reference Documentation

Ssh

Current Version: 9.5.0.90

Requires Chilkat Bundle License

A client-side SSH2 implementation for executing commands and shell sessions on Unix/Windows SSH servers.

Object Creation

Chilkat.Ssh obj = new Chilkat.Ssh();

Properties

AbortCurrent

public bool AbortCurrent {get; set; }

Introduced in version 9.5.0.58

When set to true, causes the currently running method to abort. Methods that always finish quickly (i.e.have no length file operations or network communications) are not affected. If no method is running, then this property is automatically reset to false when the next method is called. When the abort occurs, this property is reset to false. Both synchronous and asynchronous method calls can be aborted. (A synchronous method call could be aborted by setting this property from a separate thread.)

AuthFailReason

public int AuthFailReason {get; }

Introduced in version 9.5.0.52

Set to one of the following values if a call to AuthenticatePw, AuthenticatePk, or AuthenticatePwPk returns a failed status.

1: Transport failure. This is a failure to communicate with the server (i.e. the connection was lost, or a read or write failed or timed out).
2: Invalid key for public key authentication. The key was not a valid format, not a valid key, not a private key, or not the right type of key.
3: No matching authentication methods were available.
4: SSH authentication protocol error - an unexpected or invalid message was received.
5: The incorrect password or private key was provided.
6: Already authenticated. The SSH session is already authenticated.
7: Password change request: The server requires the password to be changed.

CaretControl

public bool CaretControl {get; set; }

Introduced in version 9.5.0.49

Controls whether the caret character '^' is interpreted as indicating a control character. The default value of this property is false. If set to true, then the following sequences are interpreted as control characters in any string passed to SendReqExec or ChannelSendString.

^@ 	00 	00 	NUL  	Null
^A 	01 	01 	SOH  	Start of Heading
^B 	02 	02 	STX  	Start of Text
^C 	03 	03 	ETX  	End of Text
^D 	04 	04 	EOT  	End of Transmission
^E 	05 	05 	ENQ  	Enquiry
^F 	06 	06 	ACK  	Acknowledge
^G 	07 	07 	BEL  	Bell
^H 	08 	08 	BS  	Backspace
^I 	09 	09 	HT  	Character Tabulation, Horizontal Tabulation
^J 	10 	0A 	LF  	Line Feed
^K 	11 	0B 	VT  	Line Tabulation, Vertical Tabulation
^L 	12 	0C 	FF  	Form Feed
^M 	13 	0D 	CR  	Carriage Return
^N 	14 	0E 	SO  	Shift Out
^O 	15 	0F 	SI  	Shift In
^P 	16 	10 	DLE  	Data Link Escape
^Q 	17 	11 	DC1  	Device Control One (XON)
^R 	18 	12 	DC2  	Device Control Two
^S 	19 	13 	DC3  	Device Control Three (XOFF)
^T 	20 	14 	DC4  	Device Control Four
^U 	21 	15 	NAK  	Negative Acknowledge
^V 	22 	16 	SYN  	Synchronous Idle
^W 	23 	17 	ETB  	End of Transmission Block
^X 	24 	18 	CAN  	Cancel
^Y 	25 	19 	EM  	End of medium
^Z 	26 	1A 	SUB  	Substitute
^[ 	27 	1B 	ESC  	Escape
^\ 	28 	1C 	FS  	File Separator
^] 	29 	1D 	GS  	Group Separator
^^ 	30 	1E 	RS  	Record Separator
^_ 	31 	1F 	US  	Unit Separator
^? 	127 	7F 	DEL  	Delete

ChannelOpenFailCode

public int ChannelOpenFailCode {get; }

If a request to open a channel fails, this property contains a code that identifies the reason for failure. The reason codes are defined in RFC 4254 and are reproduced here:

             Symbolic name                           reason code
             -------------                           -----------
            SSH_OPEN_ADMINISTRATIVELY_PROHIBITED          1
            SSH_OPEN_CONNECT_FAILED                       2
            SSH_OPEN_UNKNOWN_CHANNEL_TYPE                 3
            SSH_OPEN_RESOURCE_SHORTAGE                    4

ChannelOpenFailReason

public string ChannelOpenFailReason {get; }

The descriptive text corresponding to the ChannelOpenFailCode property.

ClientIdentifier

public string ClientIdentifier {get; set; }

The client-identifier string to be used when connecting to an SSH/SFTP server. Defaults to "SSH-2.0-PuTTY_Release_0.63". (This string is used to mimic PuTTY because some servers are known to disconnect from clients with unknown client identifiers.)

ClientIpAddress

public string ClientIpAddress {get; set; }

The IP address to use for computers with multiple network interfaces or IP addresses. For computers with a single network interface (i.e. most computers), this property should not be set. For multihoming computers, the default IP address is automatically used if this property is not set.

The IP address is a string such as in dotted notation using numbers, not domain names, such as "165.164.55.124".

ClientPort

public int ClientPort {get; set; }

Introduced in version 9.5.0.75

Normally left at the default value of 0, in which case a unique port is assigned with a value between 1024 and 5000. This property would only be changed if it is specifically required. For example, one customer's requirements are as follows:

"I have to connect to a Siemens PLC IP server on a technical network. This machine expects that I connect to its server from a specific IP address using a specific port otherwise the build in security disconnect the IP connection."

ConnectTimeoutMs

public int ConnectTimeoutMs {get; set; }

Maximum number of milliseconds to wait when connecting to an SSH server.

DebugLogFilePath

public string DebugLogFilePath {get; set; }

If set to a file path, causes each Chilkat method or property call to automatically append it's LastErrorText to the specified log file. The information is appended such that if a hang or crash occurs, it is possible to see the context in which the problem occurred, as well as a history of all Chilkat calls up to the point of the problem. The VerboseLogging property can be set to provide more detailed information.

This property is typically used for debugging the rare cases where a Chilkat method call hangs or generates an exception that halts program execution (i.e. crashes). A hang or crash should generally never happen. The typical causes of a hang are:

a timeout related property was set to 0 to explicitly indicate that an infinite timeout is desired,
the hang is actually a hang within an event callback (i.e. it is a hang within the application code), or
there is an internal problem (bug) in the Chilkat code that causes the hang.

DisconnectCode

public int DisconnectCode {get; }

If the SSH server sent a DISCONNECT message when closing the connection, this property contains the "reason code" as specified in RFC 4253:

           Symbolic name                                reason code
           -------------                                -----------
      SSH_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT             1
      SSH_DISCONNECT_PROTOCOL_ERROR                          2
      SSH_DISCONNECT_KEY_EXCHANGE_FAILED                     3
      SSH_DISCONNECT_RESERVED                                4
      SSH_DISCONNECT_MAC_ERROR                               5
      SSH_DISCONNECT_COMPRESSION_ERROR                       6
      SSH_DISCONNECT_SERVICE_NOT_AVAILABLE                   7
      SSH_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED          8
      SSH_DISCONNECT_HOST_KEY_NOT_VERIFIABLE                 9
      SSH_DISCONNECT_CONNECTION_LOST                        10
      SSH_DISCONNECT_BY_APPLICATION                         11
      SSH_DISCONNECT_TOO_MANY_CONNECTIONS                   12
      SSH_DISCONNECT_AUTH_CANCELLED_BY_USER                 13
      SSH_DISCONNECT_NO_MORE_AUTH_METHODS_AVAILABLE         14
      SSH_DISCONNECT_ILLEGAL_USER_NAME                      15

DisconnectReason

public string DisconnectReason {get; }

If the SSH/ server sent a DISCONNECT message when closing the connection, this property contains a descriptive string for the "reason code" as specified in RFC 4253.

EnableCompression

public bool EnableCompression {get; set; }

Introduced in version 9.5.0.56

Enables or disables the use of compression w/ the SSH connection. The default value is true, meaning that compression is used if the server supports it.

Some older SSH servers have been found that claim to support compression, but actually fail when compression is used. PuTTY does not enable compression by default. If trouble is encountered where the SSH server disconnects immediately after the connection is seemingly established (i.e. during authentication), then check to see if disabling compression resolves the problem.

ForceCipher

public string ForceCipher {get; set; }

Set to one of the following encryption algorithms to force that cipher to be used. By default, the component will automatically choose the first cipher supported by the server in the order listed here: "aes256-ctr", "aes128-ctr", "aes256-cbc", "aes128-cbc", "twofish256-cbc", "twofish128-cbc", "blowfish-cbc", "3des-cbc", "arcfour128", "arcfour256". (If blowfish is chosen, the encryption strength is 128 bits.)

Important: If this is property is set and the server does NOT support then encryption algorithm, then the Connect will fail.

HeartbeatMs

public int HeartbeatMs {get; set; }

This is the number of milliseconds between each AbortCheck event callback. The AbortCheck callback allows an application to abort any SSH operation prior to completion. If HeartbeatMs is 0 (the default), no AbortCheck event callbacks will fire.

HostKeyAlg

public string HostKeyAlg {get; set; }

Indicates the preferred host key algorithm to be used in establishing the SSH secure connection. The default is "DSS". It may be changed to "RSA" if needed. Chilkat recommends not changing this unless a problem warrants the change.

HostKeyFingerprint

public string HostKeyFingerprint {get; }

Set after connecting to an SSH server. The format of the fingerprint looks like this: "ssh-rsa 1024 68:ff:d1:4e:6c:ff:d7:b0:d6:58:73:85:07:bc:2e:d5"

HttpProxyAuthMethod

public string HttpProxyAuthMethod {get; set; }

If an HTTP proxy requiring authentication is to be used, set this property to the HTTP proxy authentication method name. Valid choices are "Basic" or "NTLM".

HttpProxyDomain

public string HttpProxyDomain {get; set; }

The NTLM authentication domain (optional) if NTLM authentication is used w/ the HTTP proxy.

HttpProxyHostname

public string HttpProxyHostname {get; set; }

If an HTTP proxy is to be used, set this property to the HTTP proxy hostname or IPv4 address (in dotted decimal notation).

More Information and Examples

SSH using HTTP Proxy

HttpProxyPassword

public string HttpProxyPassword {get; set; }

If an HTTP proxy requiring authentication is to be used, set this property to the HTTP proxy password.

HttpProxyPort

public int HttpProxyPort {get; set; }

If an HTTP proxy is to be used, set this property to the HTTP proxy port number. (Two commonly used HTTP proxy ports are 8080 and 3128.)

HttpProxyUsername

public string HttpProxyUsername {get; set; }

If an HTTP proxy requiring authentication is to be used, set this property to the HTTP proxy login name.

More Information and Examples

SSH using HTTP Proxy

IdleTimeoutMs

public int IdleTimeoutMs {get; set; }

Causes SSH operations to fail when progress for sending or receiving data halts for more than this number of milliseconds. Setting IdleTimeoutMs = 0 (the default) allows the application to wait indefinitely.

IsConnected

public bool IsConnected {get; }

Returns true if the last known state of the connection with the SSH server is "connected".

Note: The IsConnected property is set to true after successfully completing the Connect method call. The IsConnected property will only be set to false by calling Disconnect, or by the failure of another method call such that the disconnection is detected.

If the last communications with the SSH server was successful and then a long time passes with no communications, and the server disconnects because of inactivity, then IsConnected will still indicate true. A better way of testing the connection is to call SendIgnore after checking to see if IsConnected is true. (If IsConnected is false, then there is surely no connection.)

More Information and Examples

Check SSH Connection (IsConnected)

KeepSessionLog

public bool KeepSessionLog {get; set; }

Controls whether communications to/from the SSH server are saved to the SessionLog property. The default value is false. If this property is set to true, the contents of the SessionLog property will continuously grow as SSH activity transpires. The purpose of the KeepSessionLog / SessionLog properties is to help in debugging any future problems that may arise.

LastErrorHtml

public string LastErrorHtml {get; }

Provides information in HTML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

LastErrorText

public string LastErrorText {get; }

Provides information in plain-text format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

More Information and Examples

Concept of LastErrorText LastErrorText Standard Information

LastErrorXml

public string LastErrorXml {get; }

Provides information in XML format about the last method/property called. If a method call returns a value indicating failure, or behaves unexpectedly, examine this property to get more information.

LastMethodSuccess

public bool LastMethodSuccess {get; set; }

Introduced in version 9.5.0.52

Indicate whether the last method call succeeded or failed. A value of true indicates success, a value of false indicates failure. This property is automatically set for method calls. It is not modified by property accesses. The property is automatically set to indicate success for the following types of method calls:

Any method that returns a string.
Any method returning a Chilkat object, binary bytes, or a date/time.
Any method returning a standard boolean status value where success = true and failure = false.
Any method returning an integer where failure is defined by a return value less than zero.

Note: Methods that do not fit the above requirements will always set this property equal to true. For example, a method that returns no value (such as a "void" in C++) will technically always succeed.

MaxPacketSize

public int MaxPacketSize {get; set; }

The maximum packet length to be used in the SSH transport protocol. The default value is 8192.

Note: If a large amount of data is to be flowing to/from the SSH server, then setting the MaxPacketSize equal to 32768 may improve performance. For those familiar with the inner workings of the SSH protocol, this is the "maximum packet size" value that is sent in the SSH_MSG_CHANNEL_OPEN message as defined in RFC 4254.

NumOpenChannels

public int NumOpenChannels {get; }

The number of currently open channels.

PasswordChangeRequested

public bool PasswordChangeRequested {get; }

Set by the AuthenticatePw and AuthenticatePwPk methods. If the authenticate method returns a failed status, and this property is set to true, then it indicates the server requested a password change. In this case, re-call the authenticate method, but provide both the old and new passwords in the following format, where vertical bar characters encapsulate the old and new passwords:

|oldPassword|newPassword|

PreferIpv6

public bool PreferIpv6 {get; set; }

If true, then use IPv6 over IPv4 when both are supported for a particular domain. The default value of this property is false, which will choose IPv4 over IPv6.

ReadTimeoutMs

public int ReadTimeoutMs {get; set; }

The maximum amount of time to allow for reading messages/data from the SSH server. This is different from the IdleTimeoutMs property. The IdleTimeoutMs is the maximum amount of time to wait while no incoming data is arriving. The ReadTimeoutMs is the maximum amount of time to allow for reading data even if data is continuing to arrive. The default value of 0 indicates an infinite timeout value.

ReqExecCharset

public string ReqExecCharset {get; set; }

Introduced in version 9.5.0.47

Indicates the charset to be used for the command sent via the SendReqExec method. The default is "ANSI". A likely alternate value would be "utf-8".

ServerIdentifier

public string ServerIdentifier {get; }

Introduced in version 9.5.0.71

The server-identifier string received from the server during connection establishment. For example, a typical value would be similar to "SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.2".

SessionLog

public string SessionLog {get; }

Contains a log of the messages sent to/from the SSH server. To enable session logging, set the KeepSessionLog property = true. Note: This property is not a filename -- it is a string property that contains the session log data.

SocksHostname

public string SocksHostname {get; set; }

The SOCKS4/SOCKS5 hostname or IPv4 address (in dotted decimal notation). This property is only used if the SocksVersion property is set to 4 or 5).

SocksPassword

public string SocksPassword {get; set; }

The SOCKS5 password (if required). The SOCKS4 protocol does not include the use of a password, so this does not apply to SOCKS4.

SocksPort

public int SocksPort {get; set; }

The SOCKS4/SOCKS5 proxy port. The default value is 1080. This property only applies if a SOCKS proxy is used (if the SocksVersion property is set to 4 or 5).

SocksUsername

public string SocksUsername {get; set; }

The SOCKS4/SOCKS5 proxy username. This property is only used if the SocksVersion property is set to 4 or 5).

SocksVersion

public int SocksVersion {get; set; }

SocksVersion May be set to one of the following integer values:

0 - No SOCKS proxy is used. This is the default.
4 - Connect via a SOCKS4 proxy.
5 - Connect via a SOCKS5 proxy.

SoRcvBuf

public int SoRcvBuf {get; set; }

Sets the receive buffer size socket option. Normally, this property should be left unchanged. The default value is 4194304.

This property can be increased if download performance seems slow. It is recommended to be a multiple of 4096.

More Information and Examples

More Information about TCP performance and Buffer Sizes

SoSndBuf

public int SoSndBuf {get; set; }

Sets the send buffer size socket option. Normally, this property should be left unchanged. The default value is 262144.

This property can be increased if upload performance seems slow. It is recommended to be a multiple of 4096. Testing with sizes such as 512K and 1MB is reasonable.

More Information and Examples

More Information about TCP performance and Buffer Sizes

StderrToStdout

public bool StderrToStdout {get; set; }

If true, then stderr is redirected to stdout. In this case, channel output for both stdout and stderr is combined and retrievable via the following methods: GetReceivedData, GetReceivedDataN, GetReceivedText, GetReceivedTextS. If this property is false, then stderr is available separately via the GetReceivedStderr method.

The default value of this property is true.

Note: Most SSH servers do not send stderr output as "extended data" packets as specified in RFC 4254. The SessionLog may be examined to see if any CHANNEL_EXTENDED_DATA messages exist. If not, then all of the output (stdout + stderr) was sent via CHANNEL_DATA messages, and therefore it is not possible to differentiate stderr output from stdout. In summary: This feature will not work for most SSH servers.

StripColorCodes

public bool StripColorCodes {get; set; }

Introduced in version 9.5.0.67

If true, then terminal color codes are stripped from the received text. The default value of this property is true. (Color codes are non-printable escape sequences that provide information about color for text in a terminal.)

TcpNoDelay

public bool TcpNoDelay {get; set; }

Controls whether the TCP_NODELAY socket option is used for the underlying TCP/IP socket. The default value is true. This disables the Nagle algorithm and allows for better performance when small amounts of data are sent to/from the SSH server.

UncommonOptions

public string UncommonOptions {get; set; }

Introduced in version 9.5.0.73

This is a catch-all property to be used for uncommon needs. This property defaults to the empty string, and should typically remain empty.

Can be set to a list of the following comma separated keywords:

"KEX_DH_GEX_REQUEST_OLD" - Introduced in v9.5.0.73. Force the old Group Exchange message to be used. This would be used for very old SSH server implementations that do not use the RFC standard for diffie-hellman-group-exchange.
"ProtectFromVpn" - Introduced in v9.5.0.80. On Android systems, will bypass any VPN that may be installed or active.

UserAuthBanner

public string UserAuthBanner {get; set; }

Introduced in version 9.5.0.46

If a user authentication banner message is received during authentication, it will be made available here. An application can check to see if this property contains a banner string after calling StartKeyboardAuth. It is only possible for an application to display this message if it is doing keyboard-interactive authentication via the StartKeyboardAuth and ContinueKeyboardAuth methods.

VerboseLogging

public bool VerboseLogging {get; set; }

If set to true, then the contents of LastErrorText (or LastErrorXml, or LastErrorHtml) may contain more verbose information. The default value is false. Verbose logging should only be used for debugging. The potentially large quantity of logged information may adversely affect peformance.

Version

public string Version {get; }

Version of the component/library, such as "9.5.0.63"

Methods

AuthenticatePk

(awaitable) public IAsyncOperation<bool> AuthenticatePkAsyncAsync(string username, SshKey privateKey);

Authenticates with the SSH server using public-key authentication. The corresponding public key must have been installed on the SSH server for the username. Authentication will succeed if the matching privateKey is provided.

Important: When reporting problems, please send the full contents of the LastErrorText property to support@chilkatsoft.com.

Returns true for success, false for failure.

More Information and Examples

Beware of too much time between connect and authentication.Use PuTTY Key for SSH Authentication

AuthenticatePw

(awaitable) public IAsyncOperation<bool> AuthenticatePwAsyncAsync(string login, string password);

Authenticates with the SSH server using a login and password.

An SSH session always begins by first calling Connect to connect to the SSH server, and then calling either AuthenticatePw or AuthenticatePk to login.

Important: When reporting problems, please send the full contents of the LastErrorText property to support@chilkatsoft.com.
Note: To learn about how to handle password change requests, see the PasswordChangeRequested property (above).

Returns true for success, false for failure.

More Information and Examples

Beware of too much time between connect and authentication.

AuthenticatePwPk

(awaitable) public IAsyncOperation<bool> AuthenticatePwPkAsyncAsync(string username, string password, SshKey privateKey);

Authentication for SSH servers that require both a password and private key. (Most SSH servers are configured to require one or the other, but not both.)

Important: When reporting problems, please send the full contents of the LastErrorText property to support@chilkatsoft.com.

Returns true for success, false for failure.

More Information and Examples

SSH Auth Failure Reason (AuthenticatePwPk)

AuthenticateSecPw

(awaitable) public IAsyncOperation<bool> AuthenticateSecPwAsyncAsync(SecureString login, SecureString password);

Introduced in version 9.5.0.71

The same as AuthenticatePw, except the login and passwords strings are passed in secure string objects.

Returns true for success, false for failure.

More Information and Examples

SSH Authenticate Secure

AuthenticateSecPwPk

(awaitable) public IAsyncOperation<bool> AuthenticateSecPwPkAsyncAsync(SecureString username, SecureString password, SshKey privateKey);

Introduced in version 9.5.0.71

The same as AuthenticatePwPk, except the login and passwords strings are passed in secure string objects.

Returns true for success, false for failure.

ChannelIsOpen

public bool ChannelIsOpen(int channelNum);

Returns true if the channel indicated by channelNum is open. Otherwise returns false.

ChannelPoll

(awaitable) public IAsyncOperation<int> ChannelPollAsyncAsync(int channelNum, int pollTimeoutMs);

Polls for incoming data on an open channel. This method will read a channel, waiting at most pollTimeoutMs milliseconds for data to arrive. Return values are as follows:

-1 -- Error. Check the IsConnected property to see if the connection to the SSH server is still valid. Also, call ChannelIsOpen to see if the channel remains open. The LastErrorText property will contain more detailed information regarding the error.

-2 -- No additional data was received prior to the poll timeout.

>0 -- Additional data was received and the return value indicates how many bytes are available to be "picked up". Methods that read data on a channel do not return the received data directly. Instead, they return an integer to indicate how many bytes are available to be "picked up". An application picks up the available data by calling GetReceivedData or GetReceivedText.

=0 -- A zero can be returned if the channel EOF has already been received, or if the channel had already been closed.

ChannelRead

(awaitable) public IAsyncOperation<int> ChannelReadAsyncAsync(int channelNum);

Reads incoming data on an open channel. This method will read a channel, waiting at most IdleTimeoutMs milliseconds for data to arrive. Return values are as follows:

-1 -- Error. Check the IsConnected property to see if the connection to the SSH server is still valid. Also, call ChannelIsOpen to see if the channel remains open. The LastErrorText property will contain more detailed information regarding the error.

-2 -- No additional data was received prior to the IdleTimeoutMs timeout.

>0 -- Additional data was received and the return value indicates how many bytes are available to be "picked up". Methods that read data on a channel do not return the received data directly. Instead, they return an integer to indicate how many bytes are available to be "picked up". An application picks up the available data by calling GetReceivedData or GetReceivedText.

=0 -- A zero can be returned if the channel EOF has already been received, or if the channel had already been closed.

ChannelReadAndPoll

(awaitable) public IAsyncOperation<int> ChannelReadAndPollAsyncAsync(int channelNum, int pollTimeoutMs);

Reads incoming data on an open channel and continues reading until no data arrives for pollTimeoutMs milliseconds. The first read will wait a max of IdleTimeoutMs milliseconds before timing out. Subsequent reads wait a max of pollTimeoutMs milliseconds before timing out.

The idea behind ChannelReadAndPoll is to capture the output of a shell command. One might imagine the typical sequence of events when executing a shell command to be like this: (1) client sends command to server, (2) server executes the command (i.e. it's computing...), potentially taking some amount of time, (3) output is streamed back to the client. It makes sense for the client to wait a longer period of time for the first data to arrive, but once it begins arriving, the timeout can be shortened. This is exactly what ChannelReadAndPoll does -- the first timeout is controlled by the IdleTimeoutMs property, while the subsequent reads (once output starts flowing) is controlled by pollTimeoutMs.

Return values are as follows:
-1 -- Error. Check the IsConnected property to see if the connection to the SSH server is still valid. Also, call ChannelIsOpen to see if the channel remains open. The LastErrorText property will contain more detailed information regarding the error.

-2 -- No additional data was received prior to the IdleTimeoutMs timeout.

>0 -- Additional data was received and the return value indicates how many bytes are available to be "picked up". Methods that read data on a channel do not return the received data directly. Instead, they return an integer to indicate how many bytes are available to be "picked up". An application picks up the available data by calling GetReceivedData or GetReceivedText.

=0 -- A zero can be returned if the channel EOF has already been received, or if the channel had already been closed.

ChannelReadAndPoll2

(awaitable) public IAsyncOperation<int> ChannelReadAndPoll2AsyncAsync(int channelNum, int pollTimeoutMs, int maxNumBytes);

The same as ChannelReadAndPoll, except this method will return as soon as maxNumBytes is exceeded.

ChannelReceivedClose

public bool ChannelReceivedClose(int channelNum);

true if a CLOSE message has been received on the channel indicated by channelNum. When a CLOSE is received, no subsequent data should be sent in either direction -- the channel is closed in both directions.

ChannelReceivedEof

public bool ChannelReceivedEof(int channelNum);

true if an EOF message has been received on the channel indicated by channelNum. When an EOF is received, no more data will be forthcoming on the channel. However, data may still be sent in the opposite direction.

ChannelReceivedExitStatus

public bool ChannelReceivedExitStatus(int channelNum);

true if an exit status code was received on the channel. Otherwise false.

ChannelReceiveToClose

(awaitable) public IAsyncOperation<bool> ChannelReceiveToCloseAsyncAsync(int channelNum);

Reads incoming data on an open channel until the channel is closed by the server. If successful, the number of bytes available to be "picked up" can be determined by calling GetReceivedNumBytes. The received data may be retrieved by calling GetReceivedData or GetReceivedText.

Returns true for success, false for failure.

ChannelReceiveUntilMatch

(awaitable) public IAsyncOperation<bool> ChannelReceiveUntilMatchAsyncAsync(int channelNum, string matchPattern, string charset, bool caseSensitive);

Reads incoming text data on an open channel until the received data matches the matchPattern. For example, to receive data until the string "Hello World" arrives, set matchPattern equal to "*Hello World*". charset indicates the character encoding of the text being received ("iso-8859-1" for example). caseSensitive may be set to true for case sensitive matching, or false for case insensitive matching.

Returns true if text data matching matchPattern was received and is available to be picked up by calling GetReceivedText (or GetReceivedTextS). IMPORTANT: This method may read beyond the matching text. Call GetReceivedTextS to extract only the data up-to and including the matching text.

Important Notes:

It's wise to set the ReadTimeoutMs property to a non-zero value to prevent an infinite wait if the matchPattern never arrives.
If using a shell session and SendReqPty was called, set the termType = "dumb". If terminal control codes get mixed into the output stream, it could disrupt matching.
Be aware of the StderrToStdout property setting. The default value is true, which means that stderr is mixed with stdout in the output stream. This could disrupt matching. Set StderrToStdout to false to prevent this possibility.

Returns true for success, false for failure.

ChannelReceiveUntilMatchN

(awaitable) public IAsyncOperation<bool> ChannelReceiveUntilMatchNAsyncAsync(int channelNum, StringArray matchPatterns, string charset, bool caseSensitive);

The same as ChannelReceiveUntilMatch except that the method returns when any one of the match patterns specified in matchPatterns are received on the channel.

Important: It's wise to set the ReadTimeoutMs property to a non-zero value to prevent an infinite wait if of the matchPatterns ever arrives.

Returns true for success, false for failure.

More Information and Examples

SSH ReceiveUntilMatchN

ChannelRelease

public void ChannelRelease(int channelNum);

Introduced in version 9.5.0.44

Releases the internal memory resources for a channel previously opened by OpenSessionChannel, OpenCustomChannel, or OpenDirectTcpIpChannel. It is not absolutely necessary to call this method because the internal memory resources for all channels are automatically released when the SSH object instance is deleted/disposed. This method becomes necessary only when an extremely large number of channels within the same SSH object instance are opened, used, and closed over a long period of time.

ChannelSendClose

(awaitable) public IAsyncOperation<bool> ChannelSendCloseAsyncAsync(int channelNum);

Sends a CLOSE message to the server for the channel indicated by channelNum. This closes both directions of the bidirectional channel.

Returns true for success, false for failure.

ChannelSendData

(awaitable) public IAsyncOperation<bool> ChannelSendDataAsyncAsync(int channelNum, byte[] byteData);

Sends byte data on the channel indicated by channelNum.

Returns true for success, false for failure.

ChannelSendEof

(awaitable) public IAsyncOperation<bool> ChannelSendEofAsyncAsync(int channelNum);

Sends an EOF for the channel indicated by channelNum. Once an EOF is sent, no additional data may be sent on the channel. However, the channel remains open and additional data may still be received from the server.

Returns true for success, false for failure.

ChannelSendString

(awaitable) public IAsyncOperation<bool> ChannelSendStringAsyncAsync(int channelNum, string textData, string charset);

Sends character data on the channel indicated by channelNum. The text is converted to the charset indicated by charset prior to being sent. A list of supported charset values may be found on this page: Supported Charsets.

Returns true for success, false for failure.

CheckConnection

public bool CheckConnection();

Introduced in version 9.5.0.46

Returns true if the underlying TCP socket is connected to the SSH server.

ClearTtyModes

public void ClearTtyModes();

Clears the collection of TTY modes that are sent with the SendReqPty method.

Connect

(awaitable) public IAsyncOperation<bool> ConnectAsyncAsync(string domainName, int port);

Connects to the SSH server at domainName:port

The domainName may be a domain name or an IPv4 or IPv6 address in string format.

Internally, the following SSH connection protocol algorithms are supported:

Hostkey Types: ssh-rsa, ssh-dsa, ecdsa-sha2-nistp256, rsa-sha2-256, rsa-sha2-512, ssh-ed25519
Key Exchange Methods: curve25519-sha256@libssh.org, ecdh-sha2-nistp256, ecdh-sha2-nistp384, ecdh-sha2-nistp521, diffie-hellman-group-exchange-sha256, diffie-hellman-group-exchange-sha1, diffie-hellman-group14-sha1, diffie-hellman-group1-sha1
Ciphers: chacha20-poly1305@openssh.com, aes256-ctr, aes192-ctr, aes128-ctr, aes256-cbc, aes192-cbc, aes128-cbc, twofish256-cbc, twofish128-cbc, blowfish-cbc, 3des-cbc, arcfour128, arcfour256
MAC Algorithms: hmac-sha2-256, hmac-sha2-512, hmac-sha1, hmac-md5, hmac-ripemd160, hmac-sha1-96
Compression: none, zlib, zlib@openssh.com

Important: All TCP-based Internet communications, regardless of the protocol (such as HTTP, FTP, SSH, IMAP, POP3, SMTP, etc.), and regardless of SSL/TLS, begin with establishing a TCP connection to a remote host:port. External security-related infrastructure such as software firewalls (Windows Firewall), hardware firewalls, anti-virus, at either source or destination (or both) can block the connection. If the connection fails, make sure to check all potential external causes of blockage.

Returns true for success, false for failure.

ConnectThroughSsh

(awaitable) public IAsyncOperation<bool> ConnectThroughSshAsyncAsync(Ssh ssh, string hostname, int port);

Introduced in version 9.5.0.55

Connects to an SSH server through an existing SSH connection. The ssh is an existing connected and authenticated SSH object. The connection to hostname:port is made through the existing SSH connection via port-forwarding. If successful, the connection is as follows: application => ServerSSH1 => ServerSSH2. (where ServerSSH1 is the ssh and ServerSSH2 is the SSH server at hostname:port) Once connected in this way, all communications are routed through ServerSSH1 to ServerSSH2. This includes authentication -- which means the application must still call one of the Authenticate* methods to authenticate with ServerSSH2.

Returns true for success, false for failure.

More Information and Examples

Multi-Hop SSH (SSH Through SSH)

ContinueKeyboardAuth

(awaitable) public IAsyncOperation<string> ContinueKeyboardAuthAsyncAsync(string response);

Introduced in version 9.5.0.46

Continues keyboard-interactive authentication with the SSH server. The response is typically the password. If multiple responses are required (because there were multiple prompts in the infoRequest XML returned by StartKeyboardAuth), then the response should be formatted as XML (as shown below) otherwise the response simply contains the single response string.

<response>
    <response1>response to first prompt</response1>
    <response2>response to second prompt</response2>
    ...
    <responseN>response to Nth prompt</responseN>
</response>

If the interactive authentication completed with success or failure, the XML response will be:

<success>success_message</success>

or

<error>error_message</error>

If additional steps are required to complete the interactive authentication, then an XML string that provides the name, instruction, and prompts is returned. The XML has the following format:

 	<infoRequest numPrompts="N">
	    <name>name_string</name>
	    <instruction>instruction_string</instruction>
	    <prompt1 echo="1_or_0">prompt_string</prompt1>
	    ...
	    <promptN echo="1_or_0">prompt_string</promptN>
	</infoRequest>

Returns null on failure

More Information and Examples

SSH Keyboard Authentication

Disconnect

public void Disconnect();

Disconnects from the SSH server.

GetAuthMethods

(awaitable) public IAsyncOperation<string> GetAuthMethodsAsyncAsync();

Introduced in version 9.5.0.78

Queries the SSH server to find out which authentication methods it supports. Returns a string such as "publickey,password,keyboard-interactive".

This method should be called after connecting, but prior to authenticating. The method intentionally disconnects from the server after getting the authentication methods. An application may then connect again and authentication with a chosen method. (In most cases, an application knows in advance the type of authentication to be used, and this method is never called.)

Returns null on failure

More Information and Examples

Get SSH Server Authentication Methods

GetChannelExitStatus

public int GetChannelExitStatus(int channelNum);

Returns the exit status code for a channel. This method should only be called if an exit status has been received. You may check to see if the exit status was received by calling ChannelReceivedExitStatus.

GetChannelNumber

public int GetChannelNumber(int index);

Returns the channel number for the Nth open channel. Indexing begins at 0, and the number of currently open channels is indicated by the NumOpenChannels property. Returns -1 if the index is out of range.

GetChannelType

public string GetChannelType(int index);

Returns a string describing the channel type for the Nth open channel. Channel types are: "session", "x11", "forwarded-tcpip", and "direct-tcpip".

Returns null on failure

GetReceivedData

public byte[] GetReceivedData(int channelNum);

Returns the accumulated data received on the channel indicated by channelNum and clears the channel's internal receive buffer.

Returns an empty byte array on failure

GetReceivedDataN

public byte[] GetReceivedDataN(int channelNum, int maxNumBytes);

Same as GetReceivedData, but a maximum of maxNumBytes bytes is returned.

Returns an empty byte array on failure

GetReceivedNumBytes

public int GetReceivedNumBytes(int channelNum);

Returns the number of bytes available in the internal receive buffer for the specified channelNum. The received data may be retrieved by calling GetReceivedData or GetReceivedText.

GetReceivedStderr

public byte[] GetReceivedStderr(int channelNum);

Introduced in version 9.5.0.48

Returns the accumulated stderr bytes received on the channel indicated by channelNum and clears the channel's internal stderr receive buffer.

Note: If the StderrToStdout property is set to true, then stderr is automatically redirected to stdout. This is the default behavior. The following methods can be called to retrieve the channel's stdout: GetReceivedData, GetReceivedDataN, GetReceivedText, and GetReceivedTextS.

Returns an empty byte array on failure

GetReceivedStderrText

public string GetReceivedStderrText(int channelNum, string charset);

Returns the accumulated stderr text received on the channel indicated by channelNum and clears the channel's internal receive buffer. The charset indicates the charset of the character data in the internal receive buffer. A list of supported charset values may be found on this page: Supported Charsets.

Returns null on failure

GetReceivedText

public string GetReceivedText(int channelNum, string charset);

Returns the accumulated text received on the channel indicated by channelNum and clears the channel's internal receive buffer. The charset indicates the charset of the character data in the internal receive buffer. A list of supported charset values may be found on this page: Supported Charsets.

Returns null on failure

GetReceivedTextS

public string GetReceivedTextS(int channelNum, string substr, string charset);

The same as GetReceivedText, except only the text up to and including substr is returned. The text returned is removed from the internal receive buffer. If the substr was not found in the internal receive buffer, an empty string is returned and the internal receive buffer is not modified.

Returns null on failure

LastJsonData

public JsonObject LastJsonData();

Introduced in version 9.5.0.79

Provides information about what transpired in the last method called. For many methods, there is no information. For some methods, details about what transpired can be obtained via LastJsonData.

Returns null on failure

OpenCustomChannel

(awaitable) public IAsyncOperation<int> OpenCustomChannelAsyncAsync(string channelType);

Opens a custom channel with a custom server that uses the SSH protocol. The channelType is application-defined.

If successful, the channel number is returned. This is the number that should be passed to any method requiring a channel number. A -1 is returned upon failure.

OpenDirectTcpIpChannel

(awaitable) public IAsyncOperation<int> OpenDirectTcpIpChannelAsyncAsync(string targetHostname, int targetPort);

Open a direct-tcpip channel for port forwarding. Data sent on the channel via ChannelSend* methods is sent to the SSH server and then forwarded to targetHostname:targetPort. The SSH server automatically forwards data received from targetHostname:targetPort to the SSH client. Therefore, calling ChannelRead* and ChannelReceive* methods is equivalent to reading directly from targetHostname:targetPort.

If successful, the channel number is returned. This is the number that should be passed to any method requiring a channel number. A -1 is returned upon failure.

More Information and Examples

SSH Tunnel (Port Forwarding via direct-tcpip channel)

OpenSessionChannel

(awaitable) public IAsyncOperation<int> OpenSessionChannelAsyncAsync();

Opens a new session channel. Almost everything you will do with the Chilkat SSH component will involve opening a session channel. The normal sequence of operation is typically this: 1) Connect to the SSH server. 2) Authenticate. 3) Open a session channel. 4) do something on the channel such as opening a shell, execute a command, etc.

If successful, the channel number is returned. This is the number that should be passed to any method requiring a channel number. A -1 is returned upon failure.

PeekReceivedText

public string PeekReceivedText(int channelNum, string charset);

This is the same as GetReceivedText, except the internal receive buffer is not cleared.

Returns null on failure

QuickCmdCheck

(awaitable) public IAsyncOperation<int> QuickCmdCheckAsyncAsync(int pollTimeoutMs);

Introduced in version 9.5.0.65

Returns a channel number for a completed command that was previously sent via QuickCmdSend. Returns -1 if no commands have yet completed. The pollTimeoutMs indicates how long to wait (in milliseconds) for any command in progress (on any channel) to complete before returning -1.

Returns -2 if an error occurred (for example, if the connection to the SSH server was lost while checking for responses).

More Information and Examples

SSH Parallel Remote Commands on Single Server SSH Parallel Remote Commands on Multiple Servers

QuickCmdSend

(awaitable) public IAsyncOperation<int> QuickCmdSendAsyncAsync(string command);

Introduced in version 9.5.0.65

Sends a command and returns the channel number for the command that has started. This is the equivalent of calling OpenSessionChannel, followed by SendReqExec. A value of -1 is returned on failure.

The ReqExecCharset property controls the charset used for the command that is sent.

Important: When reporting problems, please send the full contents of the LastErrorText property to support@chilkatsoft.com.

More Information and Examples

SSH Parallel Remote Commands on Single Server SSH Parallel Remote Commands on Multiple Servers

QuickCommand

(awaitable) public IAsyncOperation<string> QuickCommandAsyncAsync(string command, string charset);

Introduced in version 9.5.0.65

Simplified method for executing a remote command and getting the complete output. This is the equivalent of calling OpenSessionChannel, followed by SendReqExec, then ChannelReceiveToClose, and finally GetReceivedText.

The charset indicates the charset of the command's output (such as "utf-8" or "ansi"). A list of supported charset values may be found on this page: Supported Charsets.

The ReqExecCharset property controls the charset used for the command that is sent.

Important: When reporting problems, please send the full contents of the LastErrorText property to support@chilkatsoft.com.

Returns null on failure

More Information and Examples

SSH Execute Remote Commands

QuickShell

(awaitable) public IAsyncOperation<int> QuickShellAsyncAsync();

Introduced in version 9.5.0.65

Simplified method for starting a remote shell session. It is the equivalent of calling OpenSessionChannel, followed by SendReqPty, and finally SendReqShell.

Returns the SSH channel number for the session, or -1 if not successful.

Important: When reporting problems, please send the full contents of the LastErrorText property to support@chilkatsoft.com.

More Information and Examples

SSH Quick/Simple Shell Session SSH Commands to Sophos Router Device Console

ReKey

(awaitable) public IAsyncOperation<bool> ReKeyAsyncAsync();

Initiates a re-key with the SSH server. The ReKey method does not return until the key re-exchange is complete.

RFC 4253 (the SSH Transport Layer Protocol) recommends that keys be changed after each gigabyte of transmitted data or after each hour of connection time, whichever comes sooner. Key re-exchange is a public-key operation and requires a fair amount of processing power and should not be performed too often. Either side (client or server) may initiate a key re-exchange at any time.

In most cases, a server will automatically initiate key re-exchange whenever it deems necessary, and the Chilkat SSH component handles these transparently. For example, if the Chilkat SSH component receives a re-key message from the server while in the process of receiving data on a channel, it will automatically handle the key re-exchange and the application will not even realize that an underlying key re-exchange occurred.

Returns true for success, false for failure.

SendIgnore

(awaitable) public IAsyncOperation<bool> SendIgnoreAsyncAsync();

Sends an IGNORE message to the SSH server. This is one way of verifying that the connection to the SSH server is open and valid. The SSH server does not respond to an IGNORE message. It simply ignores it. IGNORE messages are not associated with a channel (in other words, you do not need to first open a channel prior to sending an IGNORE message).

Returns true for success, false for failure.

More Information and Examples

Check SSH Connection (IsConnected)

SendReqExec

(awaitable) public IAsyncOperation<bool> SendReqExecAsyncAsync(int channelNum, string commandLine);

Initiates execution of a command on the channel specified by channelNum. The commandLine contains the full command line including any command-line parameters (just as you would type the command at a shell prompt).

This is the equivalent of running a command on a remote server via the "rexec" command. See rexec command. It is not a shell session.

Important: A channel only exists for a single request. You may not call SendReqExec multiple times on the same open channel. The reason is that the SSH server automatically closes the channel at the end of the exec. The solution is to call OpenSessionChannel to get a new channel, and then call SendReqExec using the new channel. It is OK to have more than one channel open simultaneously.

Charset: The ReqExecCharset property has been added in version 9.5.0.47. This can be set to control the character encoding of the command sent to the server. The default is ANSI. A likely alternative value is "utf-8".

Returns true for success, false for failure.

More Information and Examples

Note about sending commands that produce no output.Note about sending interactive commands such as "more"SSH Exec (Execute Command Line)Multiple SendReqExec on Same Connection Understanding SSH Automation

SendReqPty

(awaitable) public IAsyncOperation<bool> SendReqPtyAsyncAsync(int channelNum, string termType, int widthInChars, int heightInChars, int widthInPixels, int heightInPixels);

Requests a pseudo-terminal for a session channel. If the termType is a character oriented terminal ("vt100" for example), then widthInChars and heightInChars would be set to non-zero values, while widthInPixels and heightInPixels may be set to 0. If termType is pixel-oriented, such as "xterm", the reverse is true (i.e. set widthInPixels and heightInPixels, but set widthInChars and heightInChars equal to 0).

In most cases, you probably don't even want terminal emulation. In that case, try setting termType = "dumb". Terminal emulation causes terminal escape sequences to be included with shell command output. A "dumb" terminal should have no escape sequences.

Some SSH servers allow a shell to be started (via the SendReqShell method) without the need to first request a pseudo-terminal. The normal sequence for starting a remote shell is as follows:

1) Connect
2) Authenticate
3) OpenSessionChannel
4) Request a PTY via this method if necessary.
5) Start a shell by calling SendReqShell

Returns true for success, false for failure.

More Information and Examples

Understanding SSH Automation

SendReqSetEnv

(awaitable) public IAsyncOperation<bool> SendReqSetEnvAsyncAsync(int channelNum, string name, string value);

Sets an environment variable in the remote shell.

Returns true for success, false for failure.

SendReqShell

(awaitable) public IAsyncOperation<bool> SendReqShellAsyncAsync(int channelNum);

Starts a shell on an open session channel. Some SSH servers require that a PTY (pseudo-terminal) first be requested prior to starting a shell. In that case, call SendReqPty prior to calling this method. Once a shell is started, commands may be sent by calling ChannelSendString. (Don't forget to terminate commands with a CRLF).

Returns true for success, false for failure.

More Information and Examples

SSH Remote Shell Understanding SSH Automation

SendReqSignal

(awaitable) public IAsyncOperation<bool> SendReqSignalAsyncAsync(int channelNum, string signalName);

Delivers a signal to the remote process/service. signalName is one of the following: ABRT, ALRM, FPE, HUP, ILL, INT, KILL, PIPE, QUIT, SEGV, TERM, USR1, USR2. (Obviously, these are UNIX signals, so the remote SSH server would need to be a Unix/Linux system.)

Returns true for success, false for failure.

SendReqSubsystem

(awaitable) public IAsyncOperation<bool> SendReqSubsystemAsyncAsync(int channelNum, string subsystemName);

Executes a pre-defined subsystem. The SFTP protocol (Secure File Transfer Protocol) is started by the Chilkat SFTP component by starting the "sftp" subsystem.

Returns true for success, false for failure.

SendReqWindowChange

(awaitable) public IAsyncOperation<bool> SendReqWindowChangeAsyncAsync(int channelNum, int widthInChars, int heightInRows, int pixWidth, int pixHeight);

When the client-side window (terminal) size changes, this message may be sent to the server to inform it of the new size.

SendReqX11Forwarding

(awaitable) public IAsyncOperation<bool> SendReqX11ForwardingAsyncAsync(int channelNum, bool singleConnection, string authProt, string authCookie, int screenNum);

Allows the client to send an X11 forwarding request to the server. Chilkat only provides this functionality because it is a message defined in the SSH connection protocol. Chilkat has no advice for when or why it would be needed.

SendReqXonXoff

(awaitable) public IAsyncOperation<bool> SendReqXonXoffAsyncAsync(int channelNum, bool clientCanDo);

This method should be ignored and not used.

SetTtyMode

public bool SetTtyMode(string ttyName, int ttyValue);

Sets a TTY mode that is included in the SendReqPty method call. Most commonly, it is not necessary to call this method at all. Chilkat has no recommendations or expertise as to why or when a particular mode might be useful. This capability is provided because it is defined in the SSH connection protocol specification.

This method can be called multiple times to set many terminal mode flags (one per call).

The ttyValue is an integer, typically 0 or 1. Valid ttyName flag names include: VINTR, VQUIT, VERASE, VKILL, VEOF, VEOL, VEOL2, VSTART, VSTOP, VSUSP, VDSUSP, VREPRINT, VWERASE, VLNEXT, VFLUSH, VSWTCH, VSTATUS, VDISCARD, IGNPAR, PARMRK, INPCK, ISTRIP, INLCR, IGNCR, ICRNL, IUCLC, IXON, IXANY, IXOFF, IMAXBEL, ISIG, ICANON, XCASE, ECHO, ECHOE, ECHOK, ECHONL, NOFLSH, TOSTOP, IEXTEN, ECHOCTL, ECHOKE, PENDIN, OPOST, OLCUC, ONLCR, OCRNL, ONOCR, ONLRET, CS7, CS8, PARENB, PARODD, TTY_OP_ISPEED, TTY_OP_OSPEED

StartKeyboardAuth

(awaitable) public IAsyncOperation<string> StartKeyboardAuthAsyncAsync(string login);

Introduced in version 9.5.0.46

Begins keyboard-interactive authentication with the SSH server. Returns an XML string providing the name, instruction, and prompts. The XML has the following format:

 	<infoRequest numPrompts="N">
	    <name>name_string</name>
	    <instruction>instruction_string</instruction>
	    <prompt1 echo="1_or_0">prompt_string</prompt1>
	    ...
	    <promptN echo="1_or_0">prompt_string</promptN>
	</infoRequest>

If the authentication immediately succeeds because no password is required, or immediately fails, the XML response can be:

<success>success_message</success>

or

<error>error_message</error>

Returns null on failure

More Information and Examples

SSH Keyboard Authentication

WaitForChannelMessage

(awaitable) public IAsyncOperation<int> WaitForChannelMessageAsyncAsync(int pollTimeoutMs);

Introduced in version 9.5.0.48

The pollTimeoutMs is the number of milliseconds to wait. To poll, pass a value of 0 in pollTimeoutMs. Waits for an incoming message on any channel. This includes data, EOF, CLOSE, etc. If a message arrives in the alotted time, the channel number is returned. A value of -1 is returned for a timeout, and -2 for any other errors such as if the connection is lost.

Note: If a channel number is returned, the message must still be read by calling a method such as ChannelRead, ChannelReceiveUntilMatch, etc. Once the message is actually received, it may be collected by calling GetReceivedText, GetReceivedData, etc.

Events

Callbacks from asynchronous methods occur in a background thread. However, controls on the UI thread may only be accessed from the UI thread.Therefore, UI updates must be dispatched to the UI thread. One way to do this is as follows:

    public sealed partial class MainPage : Page
    {
        private Windows.UI.Core.CoreDispatcher m_dispatcher = null;

        public MainPage()
        {
            this.InitializeComponent();
            m_dispatcher = Windows.UI.Core.CoreWindow.GetForCurrentThread().Dispatcher;
        }


        async private void Http_ProgressInfo(object sender, Chilkat.ProgressInfoEventArgs eventArgs)
        {
            await m_dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
            {
                // Application code to update the UI goes here...
            });
        }

    }