SSH Task

The SSH Component enables your SSIS Package to execute remote commands over SSH.

Remarks

The SSH Task uses the SSH "exec" subsystem to remotely execute commands from your SSIS Package.

SSH Send Task

The SSH Send Task provides an ultra light-weight remote command execution client for your SSIS Package. You must first set an SSHHost. If the SSH server requires authentication, you should set the necessary SSHUser, and either SSHPassword or SSHCert depending on the SSHAuthMode you wish to use. Once the SSH server information is set, you must enter the Command you wish to execute.

Whenever called from the SSIS Package, the task will execute the given command. If the Stdin property has any data, that data will supplied to the executing command's standard input.

Once the command has finished executing, the task will write the output from the command's standard out pipe to the variable pointed to by the CommandStdOut property. It will also write the command's exit code to the variable pointed to by the CommandExitStatus property, and any data from the standard err pipe to the variable pointed to by the CommandErrorMessage property.

Sender Property List

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


Command	The command to be sent to the remote host.
CommandErrorMessage	The error message, if any, returned by the server after command execution.
CommandExitStatus	The exit code for the executed command for the current message.
CommandStdErr	The standard error output of the executed Command .
CommandStdOut	The standard output of the executed Command .
FailOnError	Controls how the component treats error codes returned by command execution.
Firewall	A set of properties related to firewall access.
LogFile	The file to write logging information to at runtime.
LogMode	What information gets logged during component execution.
Other	Defines a set of configuration settings to be used by the component.
PersistentConnection	Instructs the component whether to keep the connection to the server open.
RuntimeLicense	Specifies the component runtime license key.
SSHAcceptServerHostKey	Instructs the component to accept the server host key that matches the supplied key.
SSHAcceptServerHostKeyAcceptAny	Tells the component to accept any server certificate.
SSHAuthMode	The type of authentication used by the component.
SSHCert	The certificate to use for client authentication during the SSH handshake.
SSHCompressionAlgorithms	A comma-separated list of compression algorithms allowed for this connection.
SSHHost	The address of the SSH host.
SSHPassword	The password for SSH password-based authentication.
SSHPort	The port on the SSH server where the SSH service is running; by default, 22.
SSHUser	The username for SSH authentication.
Stdin	A string of data that will be supplied to the executing command's standard input.
Timeout	A timeout for the component.

Config Settings

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


KeyRenegotiationThreshold	Sets the threshold for the SSH Key Renegotiation.
Logoff	Whether or not to logoff from the server after execution.
LogSSHPackets	If True, detailed SSH packet logging is performed.
SSHAcceptServerHostKeyFingerPrint	Instructs the component to accept the server's host key with this fingerprint.
SSHEncryptionAlgorithms	A comma-separated list containing all allowable compression algorithms.
SSHKeyExchangeAlgorithms	Specifies the supported key exchange algorithms.
SSHMacAlgorithms	Specifies the supported Mac algorithms.
SSHPublicKeyAlgorithms	Specifies the supported public key algorithms for the server's public key.
UseStrictKeyExchange	Specifies how strict key exchange is supported.
AbsoluteTimeout	Determines whether timeouts are inactivity timeouts or absolute timeouts.
LocalHost	The name of the local host or user-assigned IP interface through which connections are initiated or accepted.
TcpNoDelay	Whether or not to delay when sending packets.
UseInternalSecurityAPI	Whether or not to use the system security libraries or an internal implementation.

Command Property (SSH Task)

The command to be sent to the remote host.

Data Type

String

Default Value

Remarks

Assigning a UNIX command to this property makes the task attempt to connect to the SSHHost and execute the command under the user's default shell. There is no need to append an end-of-line character to the command. All output from the remote application will be returned to the task.

Note: the task will terminate the connection once the remote application has finished executing.

CommandErrorMessage Property (SSH Task)

The error message, if any, returned by the server after command execution.

Data Type

String

Default Value

Remarks

After executing the Command, the server will send a notification containing the CommandExitStatus. The server may also send a textual representation of that code, which will be stored in CommandErrorMessage.

This property is not available in the Receiver.

CommandExitStatus Property (SSH Task)

The exit code for the executed command for the current message.

Data Type

Integer

Default Value

Remarks

This property is not available in the Receiver.

CommandStdErr Property (SSH Task)

The standard error output of the executed Command .

Data Type

String

Default Value

Remarks

This property will contain the standard error output of the Command once execution has completed.

This property is not available in the Receiver.

CommandStdOut Property (SSH Task)

The standard output of the executed Command .

Data Type

String

Default Value

Remarks

This property will contain the standard output of the Command once execution has completed.

This property is not available in the Receiver.

FailOnError Property (SSH Task)

Controls how the component treats error codes returned by command execution.

Data Type

Boolean

Default Value

true

Remarks

If set to True, FailOnError will cause the task to stop processing the inbound data and raise an error if the SSHHost returns an unsuccessful error code when executing the Command.

If set to False, the task will return all error information through the CommandExitStatus and CommandErrorMessage. Any standard output from the command's execution will be stored as usual in the message body.

Note: since FailOnError defaults to True, some improper command values may result in unexpected errors. In this case, it is useful to examine the standard output for any hints on proper command usage by setting FailOnError to false and writing the contents of the message to a file.

Firewall Property (SSH Task)

A set of properties related to firewall access.

Data Type

Firewall

Remarks

This is a Firewall type property which contains fields describing the firewall through which the task will attempt to connect.

LogFile Property (SSH Task)

The file to write logging information to at runtime.

Data Type

String

Default Value

Remarks

To write logging information to a file instead of using the task's logging API, set this property to a valid file on disk.

When set, any logging information is appended to the specified file and not written to the task's logging API.

LogMode Property (SSH Task)

What information gets logged during component execution.

Data Type

Enumeration

Possible Values

Verbose (0)
Info (1)
Warning (2)
Error (3)
Fatal (4)

Default Value

Remarks

This property controls what information the task logs. The possible values have the following affect on the task's behavior:


Verbose	The task will report all information regarding the transport.
Info	The task will report all major operations, as well as all warnings and errors.
Warning	The task will report any conditions that could result in unpredictable behavior as well as errors.
Error	The task will report all errors that prevent normal operations from completing.
Fatal	The task will report only serious errors that cause the task to completely stop functioning.

Other Property (SSH Task)

Defines a set of configuration settings to be used by the component.

Data Type

String

Default Value

Remarks

The task accepts one or more configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the task, access to these internal properties is provided through the Other property.

The Other property may be set to one or more configuration settings (name/value pairs). Set one setting per line. For example: configname1=value1 configname2=value2

PersistentConnection Property (SSH Task)

Instructs the component whether to keep the connection to the server open.

Data Type

Boolean

Default Value

false

Remarks

If set to true, the task will first attempt to use an existing connection. If no such connection exists, it will create a new connection. When the task completes, it will persist the connection so that the task will reuse it during the next polling interval. Setting this property to true can improve performance if you are polling very frequently.

Set the Logoff configuration to tell the task to logoff from the persisted connection after completion.

RuntimeLicense Property (SSH Task)

Specifies the component runtime license key.

Data Type

String

Default Value

Remarks

You can use the RuntimeLicense property to set the runtime key for the task license.

SSHAcceptServerHostKey Property (SSH Task)

Instructs the component to accept the server host key that matches the supplied key.

Data Type

Certificate

Remarks

If the host key that will be used by the server is known in advance, this property may be set to accept the expected key. If you are using the fingerprint, you may supply it to the SSHAcceptServerHostKeyFingerPrint setting by HEX encoding the values in the form "0a:1b:2c:3d". If this property is not set the server will not be authenticated, and the connection will be refused by the client.

Note: You may also set SSHAcceptServerHostKeyAcceptAny to True without opening the certificate selection dialog to force the adapter to unilaterally authenticate any server during the security handshake. It is strongly recommended that you use this only for testing purposes.

SSHAcceptServerHostKeyAcceptAny Property (SSH Task)

Tells the component to accept any server certificate.

Data Type

Boolean

Default Value

false

Remarks

When set to true, the task will unilaterally authenticate any server during the security handshake. It is strongly recommended that you use this only for testing purposes.

SSHAuthMode Property (SSH Task)

The type of authentication used by the component.

Data Type

Enumeration

Possible Values

None (0)
Multi Factor (1)
Password (2)
Public Key (3)
Keyboard Interactive (4)
GSSAPIWith Mic (5)

Default Value

Remarks

SSHAuthMode controls how the task attempts to authenticate when connecting to the SSHHost. The following authentication methods are available:


None	The task will attempt anonymous authentication.
Multi-Factor	The task will attempt as many authentication steps as the server requires using whatever credentials it has available.
Password	The task will send the SSHPassword to the server.
Public Key	The task will send the SSHCert to the server;
Keyboard-Interactive	The task will perform SSH keyboard-interactive authentication, responding automatically to the server's authentication prompts. It will supply the value of SSHPassword as the response to the "password" prompt. Note: this method is not truly keyboard-interactive, and the task may not recognize all prompts supplied by the server. It should be used only when the SSHHost cannot be configured to authenticate the SSHUser via more easily automated methods such as Password or Public Key.
GSSAPIWithMic	This allows the task to attempt Kerberos authentication using the GSSAPI-WITH-MIC scheme. The client will try Kerberos authentication using the value of SSHUser (single sign-on), or if SSHPassword is specified as well, it will try Kerberos authentication with alternate credentials.

SSHCert Property (SSH Task)

The certificate to use for client authentication during the SSH handshake.

Data Type

Certificate

Remarks

This property is used to assign a specific certificate for SSH client authentication.

This field is used to set a Private Key Certificate.

Private key certificates may be loaded from the registry, from files in PKCS#12 format, or from a PEM file format. If you click on the ellipses, a certificate selection dialog will open. To select a private key from the system registry, select the System Store tab or the User Store tab, and highlight the appropriate registry store. The list of certificates which have private keys will be shown below.

To select a private key certificate from a file in PKCS#12 format, select the PFX Store tab. The browse button can be used to examine the file system for PKCS#12 (.pfx or .p12) certificates. If you wish to examine the certificate, provide the password in the field provided and click on the Open button to examine the file store for certificates present. To load a certificate from PEM files, select the PEM tab. Like the PFX file selection, you can specify the password and click the Open button to examine the certificates in the PEM store, or you may paste any PEM data stored in memory.

Regardless of how you selected the certificate, once you hit the OK button, the task will attempt to verify that certificate selection. If successful, the subject of the certificate will be displayed in the property field. If the task was not able to verify the selection, a dialog box will appear instead detailing the verification error.

SSHCompressionAlgorithms Property (SSH Task)

A comma-separated list of compression algorithms allowed for this connection.

Data Type

String

Default Value

"none"

Remarks

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 task will raise an error and the connection will be aborted.

SSHCompressionAlgorithms must be set to a comma-separated list containing at least one of the following values:


zlib	Zlib compression is allowed for this connection.
none	No compression is allowed for this connection.

SSHHost Property (SSH Task)

The address of the SSH host.

Data Type

String

Default Value

Remarks

The SSHHost property specifies the IP address (IP number in dotted internet format) or Domain Name of the remote host. It is set before a connection is attempted and cannot be changed once a connection is established.

If the SSHHost property is set to a Domain Name, a DNS request is initiated, and upon successful termination of the request, the SSHHost property is set to the corresponding address. If the search is not successful, an error is logged.

SSHPassword Property (SSH Task)

The password for SSH password-based authentication.

Data Type

Password

Default Value

Remarks

SSHPassword specifies the password which is used to authenticate the client to the SSH server.

SSHPort Property (SSH Task)

The port on the SSH server where the SSH service is running; by default, 22.

Data Type

Integer

Default Value

Remarks

The SSHPort specifies a service port on the SSH host to connect to.

SSHUser Property (SSH Task)

The username for SSH authentication.

Data Type

String

Default Value

Remarks

SSHUser specifies the username which is used to authenticate the client to the SSH server. This property is required.

Stdin Property (SSH Task)

A string of data that will be supplied to the executing command's standard input.

Data Type

String

Default Value

Remarks

During execution of the Command property, if the Stdin property has any data, that data will supplied to the executing command's standard input.

This property is write-only and not available at design time.

This property is not available in the Receiver.

Timeout Property (SSH Task)

A timeout for the component.

Data Type

Integer

Default Value

Remarks

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

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

If Timeout expires, and the operation is not yet complete, the task fails with an error.

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

Optionally, the behavior of the task may be changed to absolute timeouts, i.e. the task will wait for a maximum of Timeout seconds since the beginning of the operation, without extending the timeout period during communications.

This behavior is controlled by the AbsoluteTimeout configuration setting.

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

Certificate Type

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

Store
String

The name of the certificate store for the client certificate.

The StoreType field specifies the type of the certificate store specified by Store. If the store is password protected, specify the password in StorePassword.

Store is used in conjunction with the Subject field in order to specify client certificates. If Store has a value, and Subject is set, a search for a certificate is initiated. Please refer to the Subject field for details.

Designations of certificate stores are platform-dependent.

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


MY	A certificate store holding personal certificates with their associated private keys.
CA	Certifying authority certificates.
ROOT	Root certificates.
SPC	Software publisher certificates.

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. PKCS12 certificate store).

If the provider is OpenSSL, the certificate store is a file containing a certificate and a private key. This property must be set to the name of the file.

StorePassword
String

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

StoreType
CertStoreTypes

The type of certificate store for this certificate.

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


0 (cstUser - default)	For Windows, this specifies that the certificate store is a certificate store owned by the current user. Note: This store type is not available in Java.
1 (cstMachine)	For Windows, this specifies that the certificate store is a machine store. Note: This store type is not available in Java.
2 (cstPFXFile)	The certificate store is the name of a PFX (PKCS#12) file containing certificates.
3 (cstPFXBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in PFX (PKCS#12) format.
4 (cstJKSFile)	The certificate store is the name of a Java Key Store (JKS) file containing certificates. Note: This store type is only available in Java.
5 (cstJKSBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in Java Key Store (JKS) format. Note: This store type is only available in Java.
6 (cstPEMKeyFile)	The certificate store is the name of a PEM-encoded file that contains a private key and an optional certificate.
7 (cstPEMKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains a private key and an optional certificate.
8 (cstPublicKeyFile)	The certificate store is the name of a file that contains a PEM- or DER-encoded public key certificate.
9 (cstPublicKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains a PEM- or DER-encoded public key certificate.
10 (cstSSHPublicKeyBlob)	The certificate store is a string (binary or Base64-encoded) that contains an SSH-style public key.
11 (cstP7BFile)	The certificate store is the name of a PKCS#7 file containing certificates.
12 (cstP7BBlob)	The certificate store is a string (binary) representing a certificate store in PKCS#7 format.
13 (cstSSHPublicKeyFile)	The certificate store is the name of a file that contains an SSH-style public key.
14 (cstPPKFile)	The certificate store is the name of a file that contains a PPK (PuTTY Private Key).
15 (cstPPKBlob)	The certificate store is a string (binary) that contains a PPK (PuTTY Private Key).
16 (cstXMLFile)	The certificate store is the name of a file that contains a certificate in XML format.
17 (cstXMLBlob)	The certificate store is a string that contains a certificate in XML format.
18 (cstJWKFile)	The certificate store is the name of a file that contains a JWK (JSON Web Key).
19 (cstJWKBlob)	The certificate store is a string that contains a JWK (JSON Web Key).
21 (cstBCFKSFile)	The certificate store is the name of a file that contains a BCFKS (Bouncy Castle FIPS Key Store). Note: This store type is only available in Java and .NET.
22 (cstBCFKSBlob)	The certificate store is a string (binary or Base64-encoded) representing a certificate store in BCFKS (Bouncy Castle FIPS Key Store) format. Note: This store type is only available in Java and .NET.
23 (cstPKCS11)	The certificate is present on a physical security key accessible via a PKCS#11 interface. To use a security key, the necessary data must first be collected using the CERTMGR task. The ListStoreCertificates method may be called after setting CertStoreType to `cstPKCS11`, CertStorePassword to the PIN, and CertStore to the full path of the PKCS#11 DLL. The certificate information returned in the CertList event's `CertEncoded` parameter may be saved for later use. When using a certificate, pass the previously saved security key information as the Store and set StorePassword to the PIN. Code Example. SSH Authentication with Security Key: `certmgr.CertStoreType = CertStoreTypes.cstPKCS11; certmgr.OnCertList += (s, e) => { secKeyBlob = e.CertEncoded; }; certmgr.CertStore = @"C:\Program Files\OpenSC Project\OpenSC\pkcs11\opensc-pkcs11.dll"; certmgr.CertStorePassword = "123456"; //PIN certmgr.ListStoreCertificates(); sftp.SSHCert = new Certificate(CertStoreTypes.cstPKCS11, secKeyBlob, "123456", "*"); sftp.SSHUser = "test"; sftp.SSHLogon("myhost", 22);`
99 (cstAuto)	The store type is automatically detected from the input data. This setting may be used with both public and private keys and can detect any of the supported formats automatically.

Subject
String

The subject of the certificate used for client authentication.

When this property is set, a search is performed in the current certificate store certificate with matching subject.

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

When setting the property to a partial subject, CN= should be omitted. For example, the following code would find the certificate with subject CN=Test Certificate, OU=People, C=US

Example (Searching with partial subject)

Control.CertSubject = "Test"

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

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

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

Thumbprint
String (read-only)

The thumbprint of the certificate.

This field is used to specify the thumbprint of the certificate. When there are multiple certificates in the store that have the same subject, the thumbprint will be used to distinguish between them.

Firewall Type

The firewall the component will connect through.

Remarks

When connecting through a firewall, this type is used to specify different properties of the firewall such as the firewall Host and the FirewallType.

Fields

AutoDetect
Boolean

Tells the task whether or not to automatically detect and use firewall system settings, if available.

FirewallType
FirewallTypes

Determines the type of firewall to connect through. The applicable values are the following:


fwNone (0)	No firewall (default setting).
fwTunnel (1)	Connect through a tunneling proxy. Port is set to 80.
fwSOCKS4 (2)	Connect through a SOCKS4 Proxy. Port is set to 1080.
fwSOCKS5 (3)	Connect through a SOCKS5 Proxy. Port is set to 1080.

Host
String

Name or IP address of firewall (optional). If a Host is given, requested connections will be authenticated through the specified firewall when connecting.

If the Host field is set to a Domain Name, a DNS request is initiated. Upon successful termination of the request, the Host field is set to the corresponding address. If the search is not successful, an error is returned.

Password
String

A password if authentication is to be used when connecting through the firewall. If Host is specified, the User and Password fields are used to connect and authenticate to the given firewall. If the authentication fails, a trappable error is fired.

Port
Integer

The TCP port for the firewall Host. See the description of the Host field for details.

Note that the Port is set automatically when FirewallType is set to a valid value. See the description of the FirewallType field for details.

User
String

A user name if authentication is to be used connecting through a firewall. If the Host is specified, the User and Password fields are used to connect and authenticate to the given Firewall. If the authentication fails, a trappable error is fired.

Config Settings (SSH Task)

The task accepts one or more of the following configuration settings. Configuration settings are similar in functionality to properties, but they are rarely used. In order to avoid "polluting" the property namespace of the task, access to these internal properties is provided through the Other property.

SSH Config Settings

KeyRenegotiationThreshold: Sets the threshold for the SSH Key Renegotiation.

This property allows you to specify the threshold, in the number of bytes, for the Secure Shell (SSH) key renegotiation. The default value for this property is set to 1 GB.

Example. Setting the Threshold to 500 MB: SSHComponent.Config("KeyRenegotiationThreshold=524288000")

Logoff: Whether or not to logoff from the server after execution.

This configuration is only used when PersistentConnection has been set to true. Set this to true to tell the task to logoff from the persisted connection once execution completes.

The default for this configuration setting is false.

LogSSHPackets: If True, detailed SSH packet logging is performed.

This setting can be enabled to assist in debugging. When set to True the task will include detailed information about the SSH level packets in the log. The default value is False.

SSHAcceptServerHostKeyFingerPrint: Instructs the task to accept the server's host key with this fingerprint.

This may be set to a comma-delimited collection of 16-byte MD5 fingerprints that should be accepted as the host's key. You may supply it by HEX encoding the values in the form "0a:1b:2c:3d". Example: SSHAcceptServerHostKeyFingerprint=0a:1b:2c:3d

SSHEncryptionAlgorithms: A comma-separated list containing all allowable compression algorithms.

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.

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


aes256-cbc	256-bit AES encryption in CBC mode
aes192-cbc	192-bit AES encryption in CBC mode
aes128-cbc	128-bit AES encryption in CBC mode
3des-cbc	192-bit (3-key) triple DES encryption in CBC mode
aes256-ctr	256-bit AES encryption in CTR mode
aes192-ctr	192-bit AES encryption in CTR mode
aes128-ctr	128-bit AES encryption in CTR mode
3des-ctr	192-bit (3-key) triple DES encryption in CTR mode
cast128-cbc	CAST-128 encryption
blowfish-cbc	Blowfish encryption
arcfour	ARC4 encryption
arcfour128	128-bit ARC4 encryption
arcfour256	256-bit ARC4 encryption
aes256-gcm@openssh.com	256-bit AES encryption in GCM mode.
aes128-gcm@openssh.com	128-bit AES encryption in GCM mode.

The default value is "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".

SSHKeyExchangeAlgorithms: Specifies the supported key exchange algorithms.

This configuration setting may be used to specify the list of supported key exchange algorithms used during Secure Shell (SSH) negotiation. The value should contain a comma-separated list of algorithms. Supported algorithms are as follows:

curve25519-sha256
curve25519-sha256@libssh.org
diffie-hellman-group1-sha1
diffie-hellman-group14-sha1
diffie-hellman-group14-sha256
diffie-hellman-group16-sha512
diffie-hellman-group18-sha512
diffie-hellman-group-exchange-sha256
diffie-hellman-group-exchange-sha1
ecdh-sha2-nistp256
ecdh-sha2-nistp384
ecdh-sha2-nistp521
gss-group14-sha256-toWM5Slw5Ew8Mqkay+al2g==
gss-group16-sha512-toWM5Slw5Ew8Mqkay+al2g==
gss-nistp256-sha256-toWM5Slw5Ew8Mqkay+al2g==
gss-curve25519-sha256-toWM5Slw5Ew8Mqkay+al2g==
gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==
gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==

The default value is curve25519-sha256,curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256,diffie-hellman-group16-sha512,diffie-hellman-group18-sha512,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1,gss-group14-sha256-toWM5Slw5Ew8Mqkay+al2g==,gss-group16-sha512-toWM5Slw5Ew8Mqkay+al2g==,gss-nistp256-sha256-toWM5Slw5Ew8Mqkay+al2g==,gss-curve25519-sha256-toWM5Slw5Ew8Mqkay+al2g==,gss-group14-sha1-toWM5Slw5Ew8Mqkay+al2g==,gss-gex-sha1-toWM5Slw5Ew8Mqkay+al2g==.

SSHMacAlgorithms: Specifies the supported Mac algorithms.

This configuration setting may be used to specify an alternate list of supported Mac algorithms used during SSH negotiation. This also specifies the order in which the Mac algorithms are preferred. The value should contain a comma-separated list of algorithms. Supported algorithms are as follows:

hmac-sha1
hmac-md5
hmac-sha1-96
hmac-md5-96
hmac-sha2-256
hmac-sha2-256-96
hmac-sha2-512
hmac-sha2-512-96
hmac-ripemd160
hmac-ripemd160-96
hmac-sha2-256-etm@openssh.com
hmac-sha2-512-etm@openssh.com
hmac-sha2-256-96-etm@openssh.com
hmac-sha2-512-96-etm@openssh.com
umac-64@openssh.com
umac-64-etm@openssh.com
umac-128@openssh.com
umac-128-etm@openssh.com

The default value is hmac-sha2-256,hmac-sha2-512,hmac-sha1,hmac-md5,hmac-ripemd160,hmac-sha1-96,hmac-md5-96,hmac-sha2-256-96,hmac-sha2-512-96,hmac-ripemd160-96,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,umac-64@openssh.com,umac-64-etm@openssh.com,umac-128@openssh.com,umac-128-etm@openssh.com.

SSHPublicKeyAlgorithms: Specifies the supported public key algorithms for the server's public key.

This configuration setting specifies the allowed public key algorithms for the server's public key. This list controls only the public key algorithm used when authenticating the server's public key. This list has no bearing on the public key algorithms that can be used by the client when performing public key authentication to the server. The default value is ssh-ed25519,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,rsa-sha2-256,rsa-sha2-512,ssh-rsa,ssh-dss,x509v3-sign-rsa,x509v3-sign-dss.

This setting specifies a list of signature algorithms that may be used when authenticating to the server using public key authentication. This applies only when public key authentication is performed by the client.

The setting should be a comma-separated list of algorithms. At runtime, the task will evaluate the specified algorithms, and if the algorithm is applicable to the certificate specified in SSHCert, it will be used. If the algorithm is not applicable, the task will evaluate the next algorithm. Possible values are as follows:

ssh-rsa
rsa-sha2-256
rsa-sha2-512
ssh-dss
ecdsa-sha2-nistp256
ecdsa-sha2-nistp384
ecdsa-sha2-nistp521
ssh-ed25519
x509v3-sign-rsa
x509v3-sign-dss

The default value in Windows is ssh-rsa,rsa-sha2-256,rsa-sha2-512,ssh-dss,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-ed25519.

rsa-sha2-256 and rsa-sha2-512 notes

The task will query the server for supported algorithms when connecting. If the server indicates support for rsa-sha2-256 or rsa-sha2-512 and the algorithm is present in the list defined by this setting (as in the default value), that algorithm will be used instead of ssh-rsa even when ssh-rsa appears first in the list.

For the rsa-sha2-256 and rsa-sha2-512 algorithms to be automatically preferred, the server must support the ext-info-c mechanism. In practice, older servers do not support this, and in that case, ssh-rsa will be used because it appears first in the list. Newer servers do support this mechanism, and in that case, rsa-sha2-256 or rsa-sha2-512 will be used even though it appears after ssh-rsa.

This behavior has been carefully designed to provide maximum compatibility while automatically using more secure algorithms when connecting to servers that support them.

UseStrictKeyExchange: Specifies how strict key exchange is supported.

This configuration setting controls whether strict key exchange (strict kex) is enabled to mitigate the Terrapin attack. When enabled, the task will indicate support for strict key exchange by automatically including the pseudo-algorithm kex-strict-c-v00@openssh.com for client tasks and kex-strict-s-v00@openssh.com for server tasks in the list of supported key exchange algorithms.

Because both client and server must implement strict key exchange to effectively mitigate the Terrapin attack, the task provides options to further control the behavior in different scenarios. Possible values for this setting are as follows:


`0`	Disabled. Strict key exchange is not supported in the task.
`1` (default)	Enabled, but not enforced. This setting enables strict key exchange, but if the remote host does not support strict key exchange the connection is still allowed to continue.
`2`	Enabled, but will reject affected algorithms if the remote host does not support strict key exchange. If the remote host supports strict key exchange, all algorithms may be used. If the remote host does not support strict key exchange, the connection will continue only if the selected encryption and message authentication code (MAC) algorithms are not affected by the Terrapin attack.
`3`	Required. If the remote host does not support strict key exchange, the connection will fail.

General Config Settings

AbsoluteTimeout: Determines whether timeouts are inactivity timeouts or absolute timeouts.

If AbsoluteTimeout is set to True, any method which does not complete within Timeout seconds will be aborted. By default, AbsoluteTimeout is False, and the timeout is an inactivity timeout.

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

The LocalHost configuration contains the name of the local host as obtained by the Gethostname() system call, or if the user has assigned an IP address, the value of that address.

In multihomed hosts (machines with more than one IP interface) setting LocalHost to the value of an interface will make the task initiate connections (or accept in the case of server tasks) only through that interface.

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

TcpNoDelay: Whether or not to delay when sending packets.

When set to True, the socket will send all data that are ready to send at once. When set to False, the socket will send smaller buffered packets of data at small intervals. This is known as the Nagle algorithm.

By default, this configuration setting is set to False.

UseInternalSecurityAPI: Whether or not to use the system security libraries or an internal implementation.

When set to False, the task will use the system security libraries by default to perform cryptographic functions where applicable. In this case, calls to unmanaged code will be made. In certain environments, this is not desirable. To use a completely managed security implementation, set this setting to True.

Setting this configuration setting to True tells the task to use the internal implementation instead of using the system security libraries.

On Windows, this setting is set to False by default. On Linux/macOS, this setting is set to True by default.

If using the .NET Standard Library, this setting will be True on all platforms. The .NET Standard library does not support using the system security libraries.

Note: This setting is static. The value set is applicable to all tasks used in the application.

When this value is set, the product's system dynamic link library (DLL) is no longer required as a reference, as all unmanaged code is stored in that file.